SQLite

compat

compat/*

OPT_FEATURE_FLAGS = @OPT_FEATURE_FLAGS@

TCC += $(OPT_FEATURE_FLAGS)

# Add in any optional parameters specified on the make commane line
# ie.  make "OPTS=-DSQLITE_ENABLE_FOO=1 -DSQLITE_OMIT_FOO=1".
TCC += $(OPTS)

# Add in compile-time options for some libraries used by extensions
TCC += @HAVE_ZLIB@

# Version numbers and release number for the SQLite being compiled.
#
VERSION = @VERSION@
VERSION_NUMBER = @VERSION_NUMBER@
RELEASE = @RELEASE@

USE_AMALGAMATION = @USE_AMALGAMATION@

# Object files for the SQLite library (non-amalgamation).
#
LIBOBJS0 = alter.lo analyze.lo attach.lo auth.lo \
         backup.lo bitvec.lo btmutex.lo btree.lo build.lo \
         callback.lo complete.lo ctime.lo \
         date.lo dbpage.lo dbstat.lo delete.lo \
         expr.lo fault.lo fkey.lo \
         fts3.lo fts3_aux.lo fts3_expr.lo fts3_hash.lo fts3_icu.lo \
         fts3_porter.lo fts3_snippet.lo fts3_tokenizer.lo fts3_tokenizer1.lo \
         fts3_tokenize_vtab.lo \
         fts3_unicode.lo fts3_unicode2.lo fts3_write.lo \
	 fts5.lo \
         func.lo global.lo hash.lo \
         icu.lo insert.lo json1.lo legacy.lo loadext.lo \
         main.lo malloc.lo mem0.lo mem1.lo mem2.lo mem3.lo mem5.lo \
         memdb.lo memjournal.lo \
         mutex.lo mutex_noop.lo mutex_unix.lo mutex_w32.lo \
         notify.lo opcodes.lo os.lo os_unix.lo os_win.lo \
         pager.lo parse.lo pcache.lo pcache1.lo pragma.lo prepare.lo printf.lo \
         random.lo resolve.lo rowset.lo rtree.lo \
         sqlite3session.lo select.lo sqlite3rbu.lo status.lo stmt.lo \
         table.lo threads.lo tokenize.lo treeview.lo trigger.lo \
         update.lo util.lo vacuum.lo \
         vdbe.lo vdbeapi.lo vdbeaux.lo vdbeblob.lo vdbemem.lo vdbesort.lo \
         vdbetrace.lo wal.lo walker.lo where.lo wherecode.lo whereexpr.lo \
         utf.lo vtab.lo

# Object files for the amalgamation.

  $(TOP)/src/btree.h \
  $(TOP)/src/btreeInt.h \
  $(TOP)/src/build.c \
  $(TOP)/src/callback.c \
  $(TOP)/src/complete.c \
  $(TOP)/src/ctime.c \
  $(TOP)/src/date.c \
  $(TOP)/src/dbpage.c \
  $(TOP)/src/dbstat.c \
  $(TOP)/src/delete.c \
  $(TOP)/src/expr.c \
  $(TOP)/src/fault.c \
  $(TOP)/src/fkey.c \
  $(TOP)/src/func.c \
  $(TOP)/src/global.c \
  $(TOP)/src/hash.c \
  $(TOP)/src/hash.h \
  $(TOP)/src/hwtime.h \
  $(TOP)/src/insert.c \
  $(TOP)/src/legacy.c \
  $(TOP)/src/loadext.c \
  $(TOP)/src/main.c \
  $(TOP)/src/malloc.c \
  $(TOP)/src/mem0.c \
  $(TOP)/src/mem1.c \
  $(TOP)/src/mem2.c \
  $(TOP)/src/mem3.c \
  $(TOP)/src/mem5.c \
  $(TOP)/src/memdb.c \
  $(TOP)/src/memjournal.c \
  $(TOP)/src/msvc.h \
  $(TOP)/src/mutex.c \
  $(TOP)/src/mutex.h \
  $(TOP)/src/mutex_noop.c \
  $(TOP)/src/mutex_unix.c \
  $(TOP)/src/mutex_w32.c \

  $(TOP)/src/prepare.c \
  $(TOP)/src/printf.c \
  $(TOP)/src/random.c \
  $(TOP)/src/resolve.c \
  $(TOP)/src/rowset.c \
  $(TOP)/src/select.c \
  $(TOP)/src/status.c \
  $(TOP)/src/shell.c.in \
  $(TOP)/src/sqlite.h.in \
  $(TOP)/src/sqlite3ext.h \
  $(TOP)/src/sqliteInt.h \
  $(TOP)/src/sqliteLimit.h \
  $(TOP)/src/table.c \
  $(TOP)/src/tclsqlite.c \
  $(TOP)/src/threads.c \

SRC += \
  $(TOP)/ext/session/sqlite3session.c \
  $(TOP)/ext/session/sqlite3session.h
SRC += \
  $(TOP)/ext/rbu/sqlite3rbu.h \
  $(TOP)/ext/rbu/sqlite3rbu.c
SRC += \
  $(TOP)/ext/misc/json1.c \
  $(TOP)/ext/misc/stmt.c

# Generated source code files
#
SRC += \
  keywordhash.h \
  opcodes.c \
  opcodes.h \
  parse.c \
  parse.h \
  config.h \
  shell.c \
  sqlite3.h

# Source code to the test files.
#
TESTSRC = \
  $(TOP)/src/test1.c \
  $(TOP)/src/test2.c \

  $(TOP)/src/test_fs.c \
  $(TOP)/src/test_func.c \
  $(TOP)/src/test_hexio.c \
  $(TOP)/src/test_init.c \
  $(TOP)/src/test_intarray.c \
  $(TOP)/src/test_journal.c \
  $(TOP)/src/test_malloc.c \
  $(TOP)/src/test_md5.c \
  $(TOP)/src/test_multiplex.c \
  $(TOP)/src/test_mutex.c \
  $(TOP)/src/test_onefile.c \
  $(TOP)/src/test_osinst.c \
  $(TOP)/src/test_pcache.c \
  $(TOP)/src/test_quota.c \
  $(TOP)/src/test_rtree.c \
  $(TOP)/src/test_schema.c \
  $(TOP)/src/test_server.c \
  $(TOP)/src/test_superlock.c \
  $(TOP)/src/test_syscall.c \
  $(TOP)/src/test_tclsh.c \
  $(TOP)/src/test_tclvar.c \
  $(TOP)/src/test_thread.c \
  $(TOP)/src/test_vfs.c \
  $(TOP)/src/test_windirent.c \
  $(TOP)/src/test_wsd.c       \
  $(TOP)/ext/fts3/fts3_term.c \
  $(TOP)/ext/fts3/fts3_test.c  \
  $(TOP)/ext/session/test_session.c \
  $(TOP)/ext/rbu/test_rbu.c 

# Statically linked extensions
#
TESTSRC += \
  $(TOP)/ext/expert/sqlite3expert.c \
  $(TOP)/ext/expert/test_expert.c \
  $(TOP)/ext/misc/amatch.c \
  $(TOP)/ext/misc/carray.c \
  $(TOP)/ext/misc/closure.c \
  $(TOP)/ext/misc/csv.c \
  $(TOP)/ext/misc/eval.c \
  $(TOP)/ext/misc/fileio.c \
  $(TOP)/ext/misc/fuzzer.c \
  $(TOP)/ext/fts5/fts5_tcl.c \
  $(TOP)/ext/fts5/fts5_test_mi.c \
  $(TOP)/ext/fts5/fts5_test_tok.c \
  $(TOP)/ext/misc/ieee754.c \
  $(TOP)/ext/misc/mmapwarm.c \
  $(TOP)/ext/misc/nextchar.c \
  $(TOP)/ext/misc/normalize.c \
  $(TOP)/ext/misc/percentile.c \
  $(TOP)/ext/misc/regexp.c \
  $(TOP)/ext/misc/remember.c \
  $(TOP)/ext/misc/series.c \
  $(TOP)/ext/misc/spellfix.c \
  $(TOP)/ext/misc/totype.c \
  $(TOP)/ext/misc/unionvtab.c \
  $(TOP)/ext/misc/wholenumber.c \
  $(TOP)/ext/misc/zipfile.c

# Source code to the library files needed by the test fixture
#
TESTSRC2 = \
  $(TOP)/src/attach.c \
  $(TOP)/src/backup.c \
  $(TOP)/src/bitvec.c \
  $(TOP)/src/btree.c \
  $(TOP)/src/build.c \
  $(TOP)/src/ctime.c \
  $(TOP)/src/date.c \
  $(TOP)/src/dbpage.c \
  $(TOP)/src/dbstat.c \
  $(TOP)/src/expr.c \
  $(TOP)/src/func.c \
  $(TOP)/src/insert.c \
  $(TOP)/src/wal.c \
  $(TOP)/src/main.c \
  $(TOP)/src/mem5.c \

  $(TOP)/ext/fts3/fts3.c \
  $(TOP)/ext/fts3/fts3_aux.c \
  $(TOP)/ext/fts3/fts3_expr.c \
  $(TOP)/ext/fts3/fts3_term.c \
  $(TOP)/ext/fts3/fts3_tokenizer.c \
  $(TOP)/ext/fts3/fts3_write.c \
  $(TOP)/ext/async/sqlite3async.c \
  $(TOP)/ext/session/sqlite3session.c \
  $(TOP)/ext/misc/stmt.c 

# Header files used by all library source files.
#
HDR = \
   $(TOP)/src/btree.h \
   $(TOP)/src/btreeInt.h \
   $(TOP)/src/hash.h \

# executables needed for testing
#
TESTPROGS = \
  testfixture$(TEXE) \
  sqlite3$(TEXE) \
  sqlite3_analyzer$(TEXE) \
  sqldiff$(TEXE) \
  dbhash$(TEXE) \
  sqltclsh$(TEXE)

# Databases containing fuzzer test cases
#
FUZZDATA = \
  $(TOP)/test/fuzzdata1.db \
  $(TOP)/test/fuzzdata2.db \
  $(TOP)/test/fuzzdata3.db \
  $(TOP)/test/fuzzdata4.db \
  $(TOP)/test/fuzzdata5.db

# Standard options to testfixture
#
TESTOPTS = --verbose=file --output=test-out.txt

# Extra compiler options for various shell tools
#
SHELL_OPT = -DSQLITE_ENABLE_JSON1 -DSQLITE_ENABLE_FTS4
#SHELL_OPT += -DSQLITE_ENABLE_FTS5
SHELL_OPT += -DSQLITE_ENABLE_RTREE
SHELL_OPT += -DSQLITE_ENABLE_EXPLAIN_COMMENTS
SHELL_OPT += -DSQLITE_ENABLE_UNKNOWN_SQL_FUNCTION
SHELL_OPT += -DSQLITE_ENABLE_STMTVTAB
SHELL_OPT += -DSQLITE_ENABLE_DBPAGE_VTAB
SHELL_OPT += -DSQLITE_ENABLE_DBSTAT_VTAB
SHELL_OPT += -DSQLITE_ENABLE_OFFSET_SQL_FUNC
SHELL_OPT += -DSQLITE_INTROSPECTION_PRAGMAS
FUZZERSHELL_OPT = -DSQLITE_ENABLE_JSON1
FUZZCHECK_OPT = -DSQLITE_ENABLE_JSON1 -DSQLITE_ENABLE_MEMSYS5 -DSQLITE_OSS_FUZZ
FUZZCHECK_OPT += -DSQLITE_MAX_MEMORY=50000000
FUZZCHECK_OPT += -DSQLITE_PRINTF_PRECISION_LIMIT=1000
FUZZCHECK_SRC = $(TOP)/test/fuzzcheck.c $(TOP)/test/ossfuzz.c
DBFUZZ_OPT = 

# This is the default Makefile target.  The objects listed here
# are what get build when you type just "make" with no arguments.
#
all:	sqlite3.h libsqlite3.la sqlite3$(TEXE) $(HAVE_TCL:1=libtclsqlite3.la)

libtclsqlite3.la:	tclsqlite.lo libsqlite3.la
	$(LTLINK) -no-undefined -o $@ tclsqlite.lo \
		libsqlite3.la @TCL_STUB_LIB_SPEC@ $(TLIBS) \
		-rpath "$(TCLLIBDIR)" \
		-version-info "8:6:8" \
		-avoid-version

sqlite3$(TEXE):	shell.c sqlite3.c
	$(LTLINK) $(READLINE_FLAGS) $(SHELL_OPT) -o $@ \
		shell.c sqlite3.c \
		$(LIBREADLINE) $(TLIBS) -rpath "$(libdir)"

sqldiff$(TEXE):	$(TOP)/tool/sqldiff.c sqlite3.lo sqlite3.h
	$(LTLINK) -o $@ $(TOP)/tool/sqldiff.c sqlite3.lo $(TLIBS)

dbhash$(TEXE):	$(TOP)/tool/dbhash.c sqlite3.lo sqlite3.h
	$(LTLINK) -o $@ $(TOP)/tool/dbhash.c sqlite3.lo $(TLIBS)

fuzzcheck$(TEXE):	$(FUZZCHECK_SRC) sqlite3.c sqlite3.h
	$(LTLINK) -o $@ $(FUZZCHECK_OPT) $(FUZZCHECK_SRC) sqlite3.c $(TLIBS)

ossshell$(TEXE):	$(TOP)/test/ossfuzz.c $(TOP)/test/ossshell.c sqlite3.c sqlite3.h
	$(LTLINK) -o $@ $(FUZZCHECK_OPT) $(TOP)/test/ossshell.c \
             $(TOP)/test/ossfuzz.c sqlite3.c $(TLIBS)

sessionfuzz$(TEXE):	$(TOP)/test/sessionfuzz.c sqlite3.c sqlite3.h
	$(CC) $(CFLAGS) -I. -o $@ $(TOP)/test/sessionfuzz.c $(TLIBS)

dbfuzz$(TEXE):	$(TOP)/test/dbfuzz.c sqlite3.c sqlite3.h
	$(LTLINK) -o $@ $(DBFUZZ_OPT) $(TOP)/test/dbfuzz.c sqlite3.c $(TLIBS)

mptester$(TEXE):	sqlite3.lo $(TOP)/mptest/mptest.c
	$(LTLINK) -o $@ -I. $(TOP)/mptest/mptest.c sqlite3.lo \
		$(TLIBS) -rpath "$(libdir)"

	$(TCLSH_CMD) $(TOP)/tool/vdbe-compress.tcl $(OPTS) <tsrc/vdbe.c >vdbe.new
	mv vdbe.new tsrc/vdbe.c
	cp fts5.c fts5.h tsrc
	touch .target_source

sqlite3.c:	.target_source $(TOP)/tool/mksqlite3c.tcl
	$(TCLSH_CMD) $(TOP)/tool/mksqlite3c.tcl
	cp tsrc/sqlite3ext.h .
	cp $(TOP)/ext/session/sqlite3session.h .

sqlite3ext.h:	.target_source
	cp tsrc/sqlite3ext.h .

tclsqlite3.c:	sqlite3.c
	echo '#ifndef USE_SYSTEM_SQLITE' >tclsqlite3.c

	$(LTCOMPILE) $(TEMP_STORE) -c sqlite3.c

# Rules to build the LEMON compiler generator
#
lemon$(BEXE):	$(TOP)/tool/lemon.c $(TOP)/tool/lempar.c
	$(BCC) -o $@ $(TOP)/tool/lemon.c
	cp $(TOP)/tool/lempar.c .

# Rules to build the program that generates the source-id
#
mksourceid$(BEXE):	$(TOP)/tool/mksourceid.c
	$(BCC) -o $@ $(TOP)/tool/mksourceid.c

# Rules to build individual *.o files from generated *.c files. This
# applies to:
#
#     parse.o
#     opcodes.o
#

ctime.lo:	$(TOP)/src/ctime.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/ctime.c

date.lo:	$(TOP)/src/date.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/date.c

dbpage.lo:	$(TOP)/src/dbpage.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/dbpage.c

dbstat.lo:	$(TOP)/src/dbstat.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/dbstat.c

delete.lo:	$(TOP)/src/delete.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/delete.c

expr.lo:	$(TOP)/src/expr.c $(HDR)

mem3.lo:	$(TOP)/src/mem3.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/mem3.c

mem5.lo:	$(TOP)/src/mem5.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/mem5.c

memdb.lo:	$(TOP)/src/memdb.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/memdb.c

memjournal.lo:	$(TOP)/src/memjournal.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/memjournal.c

mutex.lo:	$(TOP)/src/mutex.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/mutex.c

mutex_noop.lo:	$(TOP)/src/mutex_noop.c $(HDR)

whereexpr.lo:	$(TOP)/src/whereexpr.c $(HDR)
	$(LTCOMPILE) $(TEMP_STORE) -c $(TOP)/src/whereexpr.c

tclsqlite.lo:	$(TOP)/src/tclsqlite.c $(HDR)
	$(LTCOMPILE) -DUSE_TCL_STUBS=1 -c $(TOP)/src/tclsqlite.c

tclsqlite-shell.lo:	$(TOP)/src/tclsqlite.c $(HDR)
	$(LTCOMPILE) -DTCLSH -o $@ -c $(TOP)/src/tclsqlite.c

tclsqlite-stubs.lo:	$(TOP)/src/tclsqlite.c $(HDR)
	$(LTCOMPILE) -DUSE_TCL_STUBS=1 -o $@ -c $(TOP)/src/tclsqlite.c

tclsqlite3$(TEXE):	tclsqlite-shell.lo libsqlite3.la
	$(LTLINK) -o $@ tclsqlite-shell.lo \
		 libsqlite3.la $(LIBTCL)

parse.c:	$(TOP)/src/parse.y lemon$(BEXE) $(TOP)/tool/addopcodes.tcl
	cp $(TOP)/src/parse.y .
	rm -f parse.h
	./lemon$(BEXE) $(OPT_FEATURE_FLAGS) $(OPTS) parse.y
	mv parse.h parse.h.temp
	$(TCLSH_CMD) $(TOP)/tool/addopcodes.tcl parse.h.temp >parse.h

sqlite3.h:	$(TOP)/src/sqlite.h.in $(TOP)/manifest mksourceid$(BEXE) $(TOP)/VERSION
	$(TCLSH_CMD) $(TOP)/tool/mksqlite3h.tcl $(TOP) >sqlite3.h

keywordhash.h:	$(TOP)/tool/mkkeywordhash.c
	$(BCC) -o mkkeywordhash$(BEXE) $(OPT_FEATURE_FLAGS) $(OPTS) $(TOP)/tool/mkkeywordhash.c
	./mkkeywordhash$(BEXE) >keywordhash.h

# Source files that go into making shell.c
SHELL_SRC = \
	$(TOP)/src/shell.c.in \
        $(TOP)/ext/misc/appendvfs.c \
	$(TOP)/ext/misc/shathree.c \
	$(TOP)/ext/misc/fileio.c \
	$(TOP)/ext/misc/completion.c \
	$(TOP)/ext/misc/sqlar.c \
	$(TOP)/ext/expert/sqlite3expert.c \
	$(TOP)/ext/expert/sqlite3expert.h \
	$(TOP)/ext/misc/zipfile.c \
        $(TOP)/src/test_windirent.c

shell.c:	$(SHELL_SRC) $(TOP)/tool/mkshellc.tcl
	$(TCLSH_CMD) $(TOP)/tool/mkshellc.tcl >shell.c




# Rules to build the extension objects.
#
icu.lo:	$(TOP)/ext/icu/icu.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) -DSQLITE_CORE -c $(TOP)/ext/icu/icu.c

sqlite3session.lo:	$(TOP)/ext/session/sqlite3session.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) -DSQLITE_CORE -c $(TOP)/ext/session/sqlite3session.c

json1.lo:	$(TOP)/ext/misc/json1.c
	$(LTCOMPILE) -DSQLITE_CORE -c $(TOP)/ext/misc/json1.c

stmt.lo:	$(TOP)/ext/misc/stmt.c
	$(LTCOMPILE) -DSQLITE_CORE -c $(TOP)/ext/misc/stmt.c

# FTS5 things
#
FTS5_SRC = \
   $(TOP)/ext/fts5/fts5.h \
   $(TOP)/ext/fts5/fts5Int.h \
   $(TOP)/ext/fts5/fts5_aux.c \
   $(TOP)/ext/fts5/fts5_buffer.c \

# Rules to build the 'testfixture' application.
#
# If using the amalgamation, use sqlite3.c directly to build the test
# fixture.  Otherwise link against libsqlite3.la.  (This distinction is
# necessary because the test fixture requires non-API symbols which are
# hidden when the library is built via the amalgamation).
#
TESTFIXTURE_FLAGS  = -DSQLITE_TEST=1 -DSQLITE_CRASH_TEST=1
TESTFIXTURE_FLAGS += -DTCLSH_INIT_PROC=sqlite3TestInit
TESTFIXTURE_FLAGS += -DSQLITE_SERVER=1 -DSQLITE_PRIVATE="" -DSQLITE_CORE 
TESTFIXTURE_FLAGS += -DBUILD_sqlite
TESTFIXTURE_FLAGS += -DSQLITE_SERIES_CONSTRAINT_VERIFY=1
TESTFIXTURE_FLAGS += -DSQLITE_DEFAULT_PAGE_SIZE=1024
TESTFIXTURE_FLAGS += -DSQLITE_ENABLE_STMTVTAB
TESTFIXTURE_FLAGS += -DSQLITE_ENABLE_DBPAGE_VTAB

TESTFIXTURE_SRC0 = $(TESTSRC2) libsqlite3.la
TESTFIXTURE_SRC1 = sqlite3.c
TESTFIXTURE_SRC = $(TESTSRC) $(TOP)/src/tclsqlite.c
TESTFIXTURE_SRC += $(TESTFIXTURE_SRC$(USE_AMALGAMATION))

testfixture$(TEXE):	$(TESTFIXTURE_SRC)

	./testfixture$(TEXE) $(TOP)/test/all.test -soak=1 $(TESTOPTS)

# Do extra testing but not everything.
fulltestonly:	$(TESTPROGS) fuzztest
	./testfixture$(TEXE) $(TOP)/test/full.test

# Fuzz testing
fuzztest:	fuzzcheck$(TEXE) $(FUZZDATA) sessionfuzz$(TEXE) $(TOP)/test/sessionfuzz-data1.db
	./fuzzcheck$(TEXE) $(FUZZDATA)
	./sessionfuzz$(TEXE) run $(TOP)/test/sessionfuzz-data1.db

fastfuzztest:	fuzzcheck$(TEXE) $(FUZZDATA) sessionfuzz$(TEXE) $(TOP)/test/sessionfuzz-data1.db
	./fuzzcheck$(TEXE) --limit-mem 100M $(FUZZDATA)
	./sessionfuzz$(TEXE) run $(TOP)/test/sessionfuzz-data1.db

valgrindfuzz:	fuzzcheck$(TEXT) $(FUZZDATA) sessionfuzz$(TEXE) $(TOP)/test/sessionfuzz-data1.db
	valgrind ./fuzzcheck$(TEXE) --cell-size-check --limit-mem 10M --timeout 600 $(FUZZDATA)
	valgrind ./sessionfuzz$(TEXE) run $(TOP)/test/sessionfuzz-data1.db

# The veryquick.test TCL tests.
#
tcltest:	./testfixture$(TEXE)
	./testfixture$(TEXE) $(TOP)/test/veryquick.test $(TESTOPTS)

# Minimal testing that runs in less than 3 minutes

# A very fast test that checks basic sanity.  The name comes from
# the 60s-era electronics testing:  "Turn it on and see if smoke
# comes out."
#
smoketest:	$(TESTPROGS) fuzzcheck$(TEXE)
	./testfixture$(TEXE) $(TOP)/test/main.test $(TESTOPTS)

sqlite3_analyzer.c: sqlite3.c $(TOP)/src/tclsqlite.c $(TOP)/tool/spaceanal.tcl $(TOP)/tool/mkccode.tcl $(TOP)/tool/sqlite3_analyzer.c.in
	$(TCLSH_CMD) $(TOP)/tool/mkccode.tcl $(TOP)/tool/sqlite3_analyzer.c.in >sqlite3_analyzer.c

sqlite3_analyzer$(TEXE): sqlite3_analyzer.c
	$(LTLINK) sqlite3_analyzer.c -o $@ $(LIBTCL) $(TLIBS)

sqltclsh.c: sqlite3.c $(TOP)/src/tclsqlite.c $(TOP)/tool/sqltclsh.tcl $(TOP)/ext/misc/appendvfs.c $(TOP)/tool/mkccode.tcl $(TOP)/tool/sqltclsh.c.in	
	$(TCLSH_CMD) $(TOP)/tool/mkccode.tcl $(TOP)/tool/sqltclsh.c.in >sqltclsh.c

sqltclsh$(TEXE): sqltclsh.c
	$(LTLINK) sqltclsh.c -o $@ $(LIBTCL) $(TLIBS)

sqlite3_expert$(TEXE): $(TOP)/ext/expert/sqlite3expert.h $(TOP)/ext/expert/sqlite3expert.c $(TOP)/ext/expert/expert.c sqlite3.c
	$(LTLINK)	$(TOP)/ext/expert/sqlite3expert.h $(TOP)/ext/expert/sqlite3expert.c $(TOP)/ext/expert/expert.c sqlite3.c -o sqlite3_expert $(TLIBS)

CHECKER_DEPS =\
  $(TOP)/tool/mkccode.tcl \
  sqlite3.c \
  $(TOP)/src/tclsqlite.c \
  $(TOP)/ext/repair/sqlite3_checker.tcl \
  $(TOP)/ext/repair/checkindex.c \
  $(TOP)/ext/repair/checkfreelist.c \
  $(TOP)/ext/misc/btreeinfo.c \
  $(TOP)/ext/repair/sqlite3_checker.c.in

sqlite3_checker.c:	$(CHECKER_DEPS)
	$(TCLSH_CMD) $(TOP)/tool/mkccode.tcl $(TOP)/ext/repair/sqlite3_checker.c.in >$@

sqlite3_checker$(TEXE):	sqlite3_checker.c
	$(LTLINK) sqlite3_checker.c -o $@ $(LIBTCL) $(TLIBS)

dbdump$(TEXE): $(TOP)/ext/misc/dbdump.c sqlite3.lo
	$(LTLINK) -DDBDUMP_STANDALONE -o $@ \
           $(TOP)/ext/misc/dbdump.c sqlite3.lo $(TLIBS)

showdb$(TEXE):	$(TOP)/tool/showdb.c sqlite3.lo
	$(LTLINK) -o $@ $(TOP)/tool/showdb.c sqlite3.lo $(TLIBS)

showstat4$(TEXE):	$(TOP)/tool/showstat4.c sqlite3.lo
	$(LTLINK) -o $@ $(TOP)/tool/showstat4.c sqlite3.lo $(TLIBS)

showjournal$(TEXE):	$(TOP)/tool/showjournal.c sqlite3.lo
	$(LTLINK) -o $@ $(TOP)/tool/showjournal.c sqlite3.lo $(TLIBS)

showwal$(TEXE):	$(TOP)/tool/showwal.c sqlite3.lo
	$(LTLINK) -o $@ $(TOP)/tool/showwal.c sqlite3.lo $(TLIBS)

showshm$(TEXE):	$(TOP)/tool/showshm.c
	$(LTLINK) -o $@ $(TOP)/tool/showshm.c

changeset$(TEXE):	$(TOP)/ext/session/changeset.c sqlite3.lo
	$(LTLINK) -o $@ $(TOP)/ext/session/changeset.c sqlite3.lo $(TLIBS)

rollback-test$(TEXE):	$(TOP)/tool/rollback-test.c sqlite3.lo
	$(LTLINK) -o $@ $(TOP)/tool/rollback-test.c sqlite3.lo $(TLIBS)

LogEst$(TEXE):	$(TOP)/tool/logest.c sqlite3.h

# be used for debugging with Visual Studio.
#
!IFNDEF SPLIT_AMALGAMATION
SPLIT_AMALGAMATION = 0
!ENDIF

# <<mark>>
# Set this non-0 to have this makefile assume the Tcl shell executable
# (tclsh*.exe) is available in the PATH.  By default, this is disabled
# for compatibility with older build environments.  This setting only
# applies if TCLSH_CMD is not set manually.
#
!IFNDEF USE_TCLSH_IN_PATH
USE_TCLSH_IN_PATH = 0
!ENDIF

# Set this non-0 to use zlib, possibly compiling it from source code.
#
!IFNDEF USE_ZLIB
USE_ZLIB = 0
!ENDIF

# Set this non-0 to build zlib from source code.  This is enabled by
# default and in that case it will be assumed that the ZLIBDIR macro
# points to the top-level source code directory for zlib.
#
!IFNDEF BUILD_ZLIB
BUILD_ZLIB = 1
!ENDIF

# Set this non-0 to use the International Components for Unicode (ICU).
#
!IFNDEF USE_ICU
USE_ICU = 0
!ENDIF
# <</mark>>

!IF $(DYNAMIC_SHELL)!=0 || $(FOR_WIN10)!=0
SHELL_CORE_DEP = $(SQLITE3DLL)
!ELSE
SHELL_CORE_DEP =
!ENDIF
!ENDIF

# <<mark>>
# If zlib support is enabled, add the dependencies for it.
#
!IF $(USE_ZLIB)!=0 && $(BUILD_ZLIB)!=0
SHELL_CORE_DEP = zlib $(SHELL_CORE_DEP)
TESTFIXTURE_DEP = zlib $(TESTFIXTURE_DEP)
!ENDIF
# <</mark>>

# This is the core library that the shell executable should link with.
#
!IFNDEF SHELL_CORE_LIB
!IF $(DYNAMIC_SHELL)!=0 || $(FOR_WIN10)!=0
SHELL_CORE_LIB = $(SQLITE3LIB)
!ELSE
SHELL_CORE_LIB =

# <<mark>>
# The locations of the Tcl header and library files.  Also, the library that
# non-stubs enabled programs using Tcl must link against.  These variables
# (TCLINCDIR, TCLLIBDIR, and LIBTCL) may be overridden via the environment
# prior to running nmake in order to match the actual installed location and
# version on this machine.
#
!IFNDEF TCLDIR
TCLDIR = $(TOP)\compat\tcl
!ENDIF

!IFNDEF TCLINCDIR
TCLINCDIR = $(TCLDIR)\include
!ENDIF

!IFNDEF TCLLIBDIR
TCLLIBDIR = $(TCLDIR)\lib
!ENDIF

!IFNDEF LIBTCL
LIBTCL = tcl86.lib
!ENDIF

!IFNDEF LIBTCLSTUB
LIBTCLSTUB = tclstub86.lib
!ENDIF

!IFNDEF LIBTCLPATH
LIBTCLPATH = $(TCLDIR)\bin
!ENDIF

# The locations of the zlib header and library files.  These variables
# (ZLIBINCDIR, ZLIBLIBDIR, and ZLIBLIB) may be overridden via the environment
# prior to running nmake in order to match the actual installed (or source
# code) location on this machine.
#
!IFNDEF ZLIBDIR
ZLIBDIR = $(TOP)\compat\zlib
!ENDIF

!IFNDEF ZLIBINCDIR
ZLIBINCDIR = $(ZLIBDIR)
!ENDIF

!IFNDEF ZLIBLIBDIR
ZLIBLIBDIR = $(ZLIBDIR)
!ENDIF

!IFNDEF ZLIBLIB
!IF $(DYNAMIC_SHELL)!=0
ZLIBLIB = zdll.lib
!ELSE
ZLIBLIB = zlib.lib
!ENDIF
!ENDIF

# The locations of the ICU header and library files.  These variables
# (ICUINCDIR, ICULIBDIR, and LIBICU) may be overridden via the environment
# prior to running nmake in order to match the actual installed location on
# this machine.
#
!IFNDEF ICUDIR
ICUDIR = $(TOP)\compat\icu
!ENDIF

!IFNDEF ICUINCDIR
ICUINCDIR = $(ICUDIR)\include
!ENDIF

!IFNDEF ICULIBDIR
ICULIBDIR = $(ICUDIR)\lib
!ENDIF

!IFNDEF LIBICU
LIBICU = icuuc.lib icuin.lib
!ENDIF

# This is the command to use for tclsh - normally just "tclsh", but we may
# know the specific version we want to use.  This variable (TCLSH_CMD) may be
# overridden via the environment prior to running nmake in order to select a
# specific Tcl shell to use.
#
!IFNDEF TCLSH_CMD
!IF $(USE_TCLSH_IN_PATH)!=0 || !EXIST("$(TCLDIR)\bin\tclsh.exe")
TCLSH_CMD = tclsh
!ELSE
TCLSH_CMD = $(TCLDIR)\bin\tclsh.exe
!ENDIF
!ENDIF
# <</mark>>

# Compiler options needed for programs that use the readline() library.
#
!IFNDEF READLINE_FLAGS
READLINE_FLAGS = -DHAVE_READLINE=0

#
!IF $(DEBUG)>1 || $(SYMBOLS)!=0
TCC = $(TCC) -Zi
BCC = $(BCC) -Zi
!ENDIF

# <<mark>>
# If zlib support is enabled, add the compiler options for it.
#
!IF $(USE_ZLIB)!=0
TCC = $(TCC) -DSQLITE_HAVE_ZLIB=1
RCC = $(RCC) -DSQLITE_HAVE_ZLIB=1
TCC = $(TCC) -I$(ZLIBINCDIR)
RCC = $(RCC) -I$(ZLIBINCDIR)
!ENDIF

# If ICU support is enabled, add the compiler options for it.
#
!IF $(USE_ICU)!=0
TCC = $(TCC) -DSQLITE_ENABLE_ICU=1
RCC = $(RCC) -DSQLITE_ENABLE_ICU=1
TCC = $(TCC) -I$(TOP)\ext\icu
RCC = $(RCC) -I$(TOP)\ext\icu

LTRCOMPILE = $(RCC) -r
LTLIB = lib.exe
LTLINK = $(TCC) -Fe$@

# If requested, link to the RPCRT4 library.
#
!IF $(USE_RPCRT4_LIB)!=0
LTLIBS = $(LTLIBS) rpcrt4.lib
!ENDIF

# If a platform was set, force the linker to target that.
# Note that the vcvars*.bat family of batch files typically
# set this for you.  Otherwise, the linker will attempt
# to deduce the binary type based on the object files.
!IFDEF PLATFORM

LDFLAGS = $(LDOPTS)
!ENDIF

# <<mark>>
# Start with the Tcl related linker options.
#
!IF $(NO_TCL)==0
TCLLIBPATHS = $(TCLLIBPATHS) /LIBPATH:$(TCLLIBDIR)
TCLLIBS = $(TCLLIBS) $(LIBTCL)
!ENDIF

# If zlib support is enabled, add the linker options for it.
#
!IF $(USE_ZLIB)!=0
LTLIBPATHS = $(LTLIBPATHS) /LIBPATH:$(ZLIBLIBDIR)
LTLIBS = $(LTLIBS) $(ZLIBLIB)
!ENDIF

# If ICU support is enabled, add the linker options for it.
#
!IF $(USE_ICU)!=0
LTLIBPATHS = $(LTLIBPATHS) /LIBPATH:$(ICULIBDIR)
LTLIBS = $(LTLIBS) $(LIBICU)
!ENDIF
# <</mark>>

# You should not have to change anything below this line
###############################################################################

# <<mark>>
# Object files for the SQLite library (non-amalgamation).
#
LIBOBJS0 = vdbe.lo parse.lo alter.lo analyze.lo attach.lo auth.lo \
         backup.lo bitvec.lo btmutex.lo btree.lo build.lo \
         callback.lo complete.lo ctime.lo \
         date.lo dbpage.lo dbstat.lo delete.lo \
         expr.lo fault.lo fkey.lo \
         fts3.lo fts3_aux.lo fts3_expr.lo fts3_hash.lo fts3_icu.lo \
         fts3_porter.lo fts3_snippet.lo fts3_tokenizer.lo fts3_tokenizer1.lo \
         fts3_tokenize_vtab.lo fts3_unicode.lo fts3_unicode2.lo fts3_write.lo \
         fts5.lo \
         func.lo global.lo hash.lo \
         icu.lo insert.lo legacy.lo loadext.lo \
         main.lo malloc.lo mem0.lo mem1.lo mem2.lo mem3.lo mem5.lo \
         memdb.lo memjournal.lo \
         mutex.lo mutex_noop.lo mutex_unix.lo mutex_w32.lo \
         notify.lo opcodes.lo os.lo os_unix.lo os_win.lo \
         pager.lo pcache.lo pcache1.lo pragma.lo prepare.lo printf.lo \
         random.lo resolve.lo rowset.lo rtree.lo \
         sqlite3session.lo select.lo sqlite3rbu.lo status.lo \
         table.lo threads.lo tokenize.lo treeview.lo trigger.lo \
         update.lo util.lo vacuum.lo \

  $(TOP)\src\btmutex.c \
  $(TOP)\src\btree.c \
  $(TOP)\src\build.c \
  $(TOP)\src\callback.c \
  $(TOP)\src\complete.c \
  $(TOP)\src\ctime.c \
  $(TOP)\src\date.c \
  $(TOP)\src\dbpage.c \
  $(TOP)\src\dbstat.c \
  $(TOP)\src\delete.c \
  $(TOP)\src\expr.c \
  $(TOP)\src\fault.c \
  $(TOP)\src\fkey.c \
  $(TOP)\src\func.c \
  $(TOP)\src\global.c \
  $(TOP)\src\hash.c \
  $(TOP)\src\insert.c \
  $(TOP)\src\legacy.c \
  $(TOP)\src\loadext.c \
  $(TOP)\src\main.c \
  $(TOP)\src\malloc.c \
  $(TOP)\src\mem0.c \
  $(TOP)\src\mem1.c \
  $(TOP)\src\mem2.c \
  $(TOP)\src\mem3.c \
  $(TOP)\src\mem5.c \
  $(TOP)\src\memdb.c \
  $(TOP)\src\memjournal.c \
  $(TOP)\src\mutex.c \
  $(TOP)\src\mutex_noop.c \
  $(TOP)\src\mutex_unix.c \
  $(TOP)\src\mutex_w32.c \
  $(TOP)\src\notify.c \
  $(TOP)\src\os.c \

  $(TOP)\src\vtab.c \
  $(TOP)\src\wal.c \
  $(TOP)\src\walker.c \
  $(TOP)\src\where.c \
  $(TOP)\src\wherecode.c \
  $(TOP)\src\whereexpr.c






# Core miscellaneous files.
#
SRC03 = \
  $(TOP)\src\parse.y

# Core header files, part 1.
#

  $(TOP)\ext\fts3\fts3_unicode.c \
  $(TOP)\ext\fts3\fts3_unicode2.c \
  $(TOP)\ext\fts3\fts3_write.c \
  $(TOP)\ext\icu\icu.c \
  $(TOP)\ext\rtree\rtree.c \
  $(TOP)\ext\session\sqlite3session.c \
  $(TOP)\ext\rbu\sqlite3rbu.c \
  $(TOP)\ext\misc\json1.c \
  $(TOP)\ext\misc\stmt.c

# Extension header files, part 1.
#
SRC08 = \
  $(TOP)\ext\fts1\fts1.h \
  $(TOP)\ext\fts1\fts1_hash.h \
  $(TOP)\ext\fts1\fts1_tokenizer.h \

# Generated header files
#
SRC11 = \
  keywordhash.h \
  opcodes.h \
  parse.h \
  shell.c \
  $(SQLITE3H)

# Generated Tcl header files
#
!IF $(USE_STDCALL)!=0 || $(FOR_WIN10)!=0
SRC12 = \
  $(SQLITETCLH) \
  $(SQLITETCLDECLSH)
!ELSE
SRC12 =
!ENDIF

# All source code files.
#
SRC = $(SRC00) $(SRC01) $(SRC03) $(SRC04) $(SRC05) $(SRC06) $(SRC07) $(SRC08) $(SRC09) $(SRC10) $(SRC11)

# Source code to the test files.
#
TESTSRC = \
  $(TOP)\src\test1.c \
  $(TOP)\src\test2.c \
  $(TOP)\src\test3.c \

  $(TOP)\src\test_fs.c \
  $(TOP)\src\test_func.c \
  $(TOP)\src\test_hexio.c \
  $(TOP)\src\test_init.c \
  $(TOP)\src\test_intarray.c \
  $(TOP)\src\test_journal.c \
  $(TOP)\src\test_malloc.c \
  $(TOP)\src\test_md5.c \
  $(TOP)\src\test_multiplex.c \
  $(TOP)\src\test_mutex.c \
  $(TOP)\src\test_onefile.c \
  $(TOP)\src\test_osinst.c \
  $(TOP)\src\test_pcache.c \
  $(TOP)\src\test_quota.c \
  $(TOP)\src\test_rtree.c \
  $(TOP)\src\test_schema.c \
  $(TOP)\src\test_server.c \
  $(TOP)\src\test_superlock.c \
  $(TOP)\src\test_syscall.c \
  $(TOP)\src\test_tclsh.c \
  $(TOP)\src\test_tclvar.c \
  $(TOP)\src\test_thread.c \
  $(TOP)\src\test_vfs.c \
  $(TOP)\src\test_windirent.c \
  $(TOP)\src\test_wsd.c \
  $(TOP)\ext\fts3\fts3_term.c \
  $(TOP)\ext\fts3\fts3_test.c \
  $(TOP)\ext\rbu\test_rbu.c \
  $(TOP)\ext\session\test_session.c

# Statically linked extensions.
#
TESTEXT = \
  $(TOP)\ext\expert\sqlite3expert.c \
  $(TOP)\ext\expert\test_expert.c \
  $(TOP)\ext\misc\amatch.c \
  $(TOP)\ext\misc\carray.c \
  $(TOP)\ext\misc\closure.c \
  $(TOP)\ext\misc\csv.c \
  $(TOP)\ext\misc\eval.c \
  $(TOP)\ext\misc\fileio.c \
  $(TOP)\ext\misc\fuzzer.c \
  $(TOP)\ext\fts5\fts5_tcl.c \
  $(TOP)\ext\fts5\fts5_test_mi.c \
  $(TOP)\ext\fts5\fts5_test_tok.c \
  $(TOP)\ext\misc\ieee754.c \
  $(TOP)\ext\misc\mmapwarm.c \
  $(TOP)\ext\misc\nextchar.c \
  $(TOP)\ext\misc\normalize.c \
  $(TOP)\ext\misc\percentile.c \
  $(TOP)\ext\misc\regexp.c \
  $(TOP)\ext\misc\remember.c \
  $(TOP)\ext\misc\series.c \
  $(TOP)\ext\misc\spellfix.c \
  $(TOP)\ext\misc\totype.c \
  $(TOP)\ext\misc\unionvtab.c \
  $(TOP)\ext\misc\wholenumber.c

# If use of zlib is enabled, add the "zipfile.c" source file.
#
!IF $(USE_ZLIB)!=0
TESTEXT = $(TESTEXT) $(TOP)\ext\misc\zipfile.c
!ENDIF

# Source code to the library files needed by the test fixture
# (non-amalgamation)
#
TESTSRC2 = \
  $(SRC00) \
  $(SRC01) \

# executables needed for testing
#
TESTPROGS = \
  testfixture.exe \
  $(SQLITE3EXE) \
  sqlite3_analyzer.exe \
  sqlite3_checker.exe \
  sqldiff.exe \
  dbhash.exe \
  sqltclsh.exe

# Databases containing fuzzer test cases
#
FUZZDATA = \
  $(TOP)\test\fuzzdata1.db \
  $(TOP)\test\fuzzdata2.db \
  $(TOP)\test\fuzzdata3.db \
  $(TOP)\test\fuzzdata4.db \
  $(TOP)\test\fuzzdata5.db
# <</mark>>

# Additional compiler options for the shell.  These are only effective
# when the shell is not being dynamically linked.
#
!IF $(DYNAMIC_SHELL)==0 && $(FOR_WIN10)==0
SHELL_COMPILE_OPTS = $(SHELL_COMPILE_OPTS) -DSQLITE_ENABLE_JSON1 -DSQLITE_ENABLE_FTS4 -DSQLITE_ENABLE_EXPLAIN_COMMENTS -DSQLITE_ENABLE_STMTVTAB
SHELL_COMPILE_OPTS = $(SHELL_COMPILE_OPTS) -DSQLITE_ENABLE_DBPAGE_VTAB -DSQLITE_ENABLE_DBSTAT_VTAB
SHELL_COMPILE_OPTS = $(SHELL_COMPILE_OPTS) -DSQLITE_ENABLE_OFFSET_SQL_FUNC -DSQLITE_INTROSPECTION_PRAGMAS
SHELL_COMPILE_OPTS = $(SHELL_COMPILE_OPTS) -DSQLITE_ENABLE_RTREE
!ENDIF

# <<mark>>
# Extra compiler options for various test tools.
#
MPTESTER_COMPILE_OPTS = -DSQLITE_ENABLE_JSON1 -DSQLITE_ENABLE_FTS5
FUZZERSHELL_COMPILE_OPTS = -DSQLITE_ENABLE_JSON1
FUZZCHECK_COMPILE_OPTS = -DSQLITE_ENABLE_JSON1 -DSQLITE_ENABLE_MEMSYS5 -DSQLITE_OSS_FUZZ -DSQLITE_MAX_MEMORY=50000000 -DSQLITE_PRINTF_PRECISION_LIMIT=1000
FUZZCHECK_SRC = $(TOP)\test\fuzzcheck.c $(TOP)\test\ossfuzz.c
OSSSHELL_SRC = $(TOP)\test\ossshell.c $(TOP)\test\ossfuzz.c
DBFUZZ_COMPILE_OPTS = -DSQLITE_THREADSAFE=0 -DSQLITE_OMIT_LOAD_EXTENSION
KV_COMPILE_OPTS = -DSQLITE_THREADSAFE=0 -DSQLITE_DIRECT_OVERFLOW_READ

ST_COMPILE_OPTS = -DSQLITE_THREADSAFE=0

# Standard options to testfixture.
#
TESTOPTS = --verbose=file --output=test-out.txt

# Extra targets for the "all" target that require Tcl.
#
!IF $(NO_TCL)==0
ALL_TCL_TARGETS = libtclsqlite3.lib
!ELSE
ALL_TCL_TARGETS =
!ENDIF
# <</mark>>

# This is the default Makefile target.  The objects listed here
# are what get build when you type just "make" with no arguments.
#
core:	dll libsqlite3.lib shell

# Targets that require the Tcl library.
#
tcl:	$(ALL_TCL_TARGETS)

# This Makefile target builds all of the standard binaries.
#
all:	core tcl

# Dynamic link library section.
#
dll:	$(SQLITE3DLL)

# Shell executable.
#

$(SQLITE3DLL):	$(LIBOBJ) $(LIBRESOBJS) $(CORE_LINK_DEP)
	$(LD) $(LDFLAGS) $(LTLINKOPTS) $(LTLIBPATHS) /DLL $(CORE_LINK_OPTS) /OUT:$@ $(LIBOBJ) $(LIBRESOBJS) $(LTLIBS) $(TLIBS)

# <<block2>>
sqlite3.def:	libsqlite3.lib
	echo EXPORTS > sqlite3.def
	dumpbin /all libsqlite3.lib \
		| $(TCLSH_CMD) $(TOP)\tool\replace.tcl include "^\s+1 _?(sqlite3(?:session|changeset|changegroup)?_[^@]*)(?:@\d+)?$$" \1 \
		| sort >> sqlite3.def
# <</block2>>

$(SQLITE3EXE):	shell.c $(SHELL_CORE_DEP) $(LIBRESOBJS) $(SHELL_CORE_SRC) $(SQLITE3H)
	$(LTLINK) $(SHELL_COMPILE_OPTS) $(READLINE_FLAGS) shell.c $(SHELL_CORE_SRC) \
		/link $(SQLITE3EXEPDB) $(LDFLAGS) $(LTLINKOPTS) $(SHELL_LINK_OPTS) $(LTLIBPATHS) $(LIBRESOBJS) $(LIBREADLINE) $(LTLIBS) $(TLIBS)

# <<mark>>
sqldiff.exe:	$(TOP)\tool\sqldiff.c $(SQLITE3C) $(SQLITE3H)
	$(LTLINK) $(NO_WARN) $(TOP)\tool\sqldiff.c $(SQLITE3C) /link $(LDFLAGS) $(LTLINKOPTS)

dbhash.exe:	$(TOP)\tool\dbhash.c $(SQLITE3C) $(SQLITE3H)
	$(LTLINK) $(NO_WARN) $(TOP)\tool\dbhash.c $(SQLITE3C) /link $(LDFLAGS) $(LTLINKOPTS)

scrub.exe:	$(TOP)\ext\misc\scrub.c $(SQLITE3C) $(SQLITE3H)
	$(LTLINK) $(NO_WARN) -DSCRUB_STANDALONE=1 $(TOP)\ext\misc\scrub.c $(SQLITE3C) /link $(LDFLAGS) $(LTLINKOPTS)

srcck1.exe:	$(TOP)\tool\srcck1.c
	$(BCC) $(NO_WARN) -Fe$@ $(TOP)\tool\srcck1.c

sourcetest:	srcck1.exe sqlite3.c
	srcck1.exe sqlite3.c

fuzzershell.exe:	$(TOP)\tool\fuzzershell.c $(SQLITE3C) $(SQLITE3H)
	$(LTLINK) $(NO_WARN) $(FUZZERSHELL_COMPILE_OPTS) $(TOP)\tool\fuzzershell.c $(SQLITE3C) /link $(LDFLAGS) $(LTLINKOPTS)

dbfuzz.exe:	$(TOP)\test\dbfuzz.c $(SQLITE3C) $(SQLITE3H)
	$(LTLINK) $(NO_WARN) $(DBFUZZ_COMPILE_OPTS) $(TOP)\test\dbfuzz.c $(SQLITE3C) /link $(LDFLAGS) $(LTLINKOPTS)

fuzzcheck.exe:	$(FUZZCHECK_SRC) $(SQLITE3C) $(SQLITE3H)
	$(LTLINK) $(NO_WARN) $(FUZZCHECK_COMPILE_OPTS) $(FUZZCHECK_SRC) $(SQLITE3C) /link $(LDFLAGS) $(LTLINKOPTS)

ossshell.exe:	$(OSSSHELL_SRC) $(SQLITE3C) $(SQLITE3H)
	$(LTLINK) $(NO_WARN) $(FUZZCHECK_COMPILE_OPTS) $(OSSSHELL_SRC) $(SQLITE3C) /link $(LDFLAGS) $(LTLINKOPTS)

sessionfuzz.exe:	zlib $(TOP)\test\sessionfuzz.c $(SQLITE3C) $(SQLITE3H)
	$(LTLINK) $(NO_WARN) -I$(ZLIBINCDIR) $(TOP)\test\sessionfuzz.c /link $(LDFLAGS) $(LTLINKOPTS) /LIBPATH:$(ZLIBLIBDIR) $(ZLIBLIB)

mptester.exe:	$(TOP)\mptest\mptest.c $(SQLITE3C) $(SQLITE3H)
	$(LTLINK) $(NO_WARN) $(MPTESTER_COMPILE_OPTS) $(TOP)\mptest\mptest.c $(SQLITE3C) /link $(LDFLAGS) $(LTLINKOPTS)

MPTEST1 = mptester mptest.db $(TOP)\mptest\crash01.test --repeat 20
MPTEST2 = mptester mptest.db $(TOP)\mptest\multiwrite01.test --repeat 20

mptest:	mptester.exe

# all that automatic generation.
#
.target_source:	$(SRC) $(TOP)\tool\vdbe-compress.tcl fts5.c $(SQLITE_TCL_DEP)
	-rmdir /Q/S tsrc 2>NUL
	-mkdir tsrc
	for %i in ($(SRC00)) do copy /Y %i tsrc
	for %i in ($(SRC01)) do copy /Y %i tsrc

	for %i in ($(SRC03)) do copy /Y %i tsrc
	for %i in ($(SRC04)) do copy /Y %i tsrc
	for %i in ($(SRC05)) do copy /Y %i tsrc
	for %i in ($(SRC06)) do copy /Y %i tsrc
	for %i in ($(SRC07)) do copy /Y %i tsrc
	for %i in ($(SRC08)) do copy /Y %i tsrc
	for %i in ($(SRC09)) do copy /Y %i tsrc
	for %i in ($(SRC10)) do copy /Y %i tsrc
	for %i in ($(SRC11)) do copy /Y %i tsrc
	for %i in ($(SRC12)) do copy /Y %i tsrc
	copy /Y fts5.c tsrc
	copy /Y fts5.h tsrc
	del /Q tsrc\sqlite.h.in tsrc\parse.y 2>NUL
	$(TCLSH_CMD) $(TOP)\tool\vdbe-compress.tcl $(OPTS) < tsrc\vdbe.c > vdbe.new
	move vdbe.new tsrc\vdbe.c
	echo > .target_source

sqlite3.c:	.target_source sqlite3ext.h $(MKSQLITE3C_TOOL)
	$(TCLSH_CMD) $(MKSQLITE3C_TOOL) $(MKSQLITE3C_ARGS)

	copy $(TOP)\ext\session\sqlite3session.h .

sqlite3-all.c:	sqlite3.c $(TOP)\tool\split-sqlite3c.tcl
	$(TCLSH_CMD) $(TOP)\tool\split-sqlite3c.tcl
# <</mark>>

# Rule to build the amalgamation

lempar.c:	$(TOP)\tool\lempar.c
	copy $(TOP)\tool\lempar.c .

lemon.exe:	$(TOP)\tool\lemon.c lempar.c
	$(BCC) $(NO_WARN) -Daccess=_access \
		-Fe$@ $(TOP)\tool\lemon.c /link $(LDFLAGS) $(NLTLINKOPTS) $(NLTLIBPATHS)

# <<mark>>
# Rules to build the source-id generator tool
#
mksourceid.exe:	$(TOP)\tool\mksourceid.c
	$(BCC) $(NO_WARN) -Fe$@ $(TOP)\tool\mksourceid.c /link $(LDFLAGS) $(NLTLINKOPTS) $(NLTLIBPATHS)

# Rules to build individual *.lo files from generated *.c files. This
# applies to:
#
#     parse.lo
#     opcodes.lo
#
parse.lo:	parse.c $(HDR)

ctime.lo:	$(TOP)\src\ctime.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\ctime.c

date.lo:	$(TOP)\src\date.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\date.c

dbpage.lo:	$(TOP)\src\dbpage.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\dbpage.c

dbstat.lo:	$(TOP)\src\dbstat.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\dbstat.c

delete.lo:	$(TOP)\src\delete.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\delete.c

expr.lo:	$(TOP)\src\expr.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\expr.c

mem3.lo:	$(TOP)\src\mem3.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\mem3.c

mem5.lo:	$(TOP)\src\mem5.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\mem5.c

memdb.lo:	$(TOP)\src\memdb.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\memdb.c

memjournal.lo:	$(TOP)\src\memjournal.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\memjournal.c

mutex.lo:	$(TOP)\src\mutex.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\mutex.c

mutex_noop.lo:	$(TOP)\src\mutex_noop.c $(HDR)

whereexpr.lo:	$(TOP)\src\whereexpr.c $(HDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(TOP)\src\whereexpr.c

tclsqlite.lo:	$(TOP)\src\tclsqlite.c $(HDR) $(SQLITE_TCL_DEP)
	$(LTCOMPILE) $(NO_WARN) -DUSE_TCL_STUBS=1 -DBUILD_sqlite -I$(TCLINCDIR) -c $(TOP)\src\tclsqlite.c

tclsqlite-shell.lo:	$(TOP)\src\tclsqlite.c $(HDR) $(SQLITE_TCL_DEP)
	$(LTCOMPILE) $(NO_WARN) -DTCLSH -DBUILD_sqlite -I$(TCLINCDIR) -c $(TOP)\src\tclsqlite.c

tclsqlite3.exe:	tclsqlite-shell.lo $(SQLITE3C) $(SQLITE3H) $(LIBRESOBJS)
	$(LTLINK) $(SQLITE3C) /link $(LDFLAGS) $(LTLINKOPTS) $(TCLLIBPATHS) $(LTLIBPATHS) /OUT:$@ tclsqlite-shell.lo $(LIBRESOBJS) $(TCLLIBS) $(LTLIBS) $(TLIBS)

# Rules to build opcodes.c and opcodes.h
#
opcodes.c:	opcodes.h $(TOP)\tool\mkopcodec.tcl
	$(TCLSH_CMD) $(TOP)\tool\mkopcodec.tcl opcodes.h > opcodes.c

opcodes.h:	parse.h $(TOP)\src\vdbe.c $(TOP)\tool\mkopcodeh.tcl
	type parse.h $(TOP)\src\vdbe.c | $(TCLSH_CMD) $(TOP)\tool\mkopcodeh.tcl > opcodes.h

# Rules to build parse.c and parse.h - the outputs of lemon.
#
parse.h:	parse.c

parse.c:	$(TOP)\src\parse.y lemon.exe $(TOP)\tool\addopcodes.tcl
	del /Q parse.y parse.h parse.h.temp 2>NUL
	copy $(TOP)\src\parse.y .
	.\lemon.exe $(REQ_FEATURE_FLAGS) $(OPT_FEATURE_FLAGS) $(EXT_FEATURE_FLAGS) $(OPTS) parse.y
	move parse.h parse.h.temp
	$(TCLSH_CMD) $(TOP)\tool\addopcodes.tcl parse.h.temp > parse.h

$(SQLITE3H):	$(TOP)\src\sqlite.h.in $(TOP)\manifest mksourceid.exe $(TOP)\VERSION
	$(TCLSH_CMD) $(TOP)\tool\mksqlite3h.tcl $(TOP:\=/) > $(SQLITE3H) $(MKSQLITE3H_ARGS)

sqlite3ext.h:	.target_source
!IF $(USE_STDCALL)!=0 || $(FOR_WIN10)!=0
	type tsrc\sqlite3ext.h | $(TCLSH_CMD) $(TOP)\tool\replace.tcl regsub "\(\*\)" "(SQLITE_CALLBACK *)" \
		| $(TCLSH_CMD) $(TOP)\tool\replace.tcl regsub "\(\*" "(SQLITE_APICALL *" > sqlite3ext.h
	copy /Y sqlite3ext.h tsrc\sqlite3ext.h
!ELSE
	copy /Y tsrc\sqlite3ext.h sqlite3ext.h
!ENDIF

mkkeywordhash.exe:	$(TOP)\tool\mkkeywordhash.c
	$(BCC) $(NO_WARN) -Fe$@ $(REQ_FEATURE_FLAGS) $(OPT_FEATURE_FLAGS) $(EXT_FEATURE_FLAGS) $(OPTS) \
		$(TOP)\tool\mkkeywordhash.c /link $(LDFLAGS) $(NLTLINKOPTS) $(NLTLIBPATHS)

keywordhash.h:	$(TOP)\tool\mkkeywordhash.c mkkeywordhash.exe
	.\mkkeywordhash.exe > keywordhash.h

# Source files that go into making shell.c
SHELL_SRC = \
	$(TOP)\src\shell.c.in \
	$(TOP)\ext\misc\appendvfs.c \
	$(TOP)\ext\misc\shathree.c \
	$(TOP)\ext\misc\fileio.c \
	$(TOP)\ext\misc\completion.c \
	$(TOP)\ext\expert\sqlite3expert.c \
	$(TOP)\ext\expert\sqlite3expert.h \
	$(TOP)\src\test_windirent.c

# If use of zlib is enabled, add the "zipfile.c" source file.
#
!IF $(USE_ZLIB)!=0
SHELL_SRC = $(SHELL_SRC) $(TOP)\ext\misc\sqlar.c
SHELL_SRC = $(SHELL_SRC) $(TOP)\ext\misc\zipfile.c
!ENDIF

shell.c:	$(SHELL_SRC) $(TOP)\tool\mkshellc.tcl
	$(TCLSH_CMD) $(TOP)\tool\mkshellc.tcl > shell.c

zlib:
	pushd $(ZLIBDIR) && $(MAKE) /f win32\Makefile.msc clean $(ZLIBLIB) && popd

# Rules to build the extension objects.
#
icu.lo:	$(TOP)\ext\icu\icu.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) $(NO_WARN) -DSQLITE_CORE -c $(TOP)\ext\icu\icu.c

fts2.lo:	$(TOP)\ext\fts2\fts2.c $(HDR) $(EXTHDR)

   fts5parse.c fts5parse.h \
   $(TOP)\ext\fts5\fts5_storage.c \
   $(TOP)\ext\fts5\fts5_tokenize.c \
   $(TOP)\ext\fts5\fts5_unicode2.c \
   $(TOP)\ext\fts5\fts5_varint.c \
   $(TOP)\ext\fts5\fts5_vocab.c

LSM1_SRC = \
   $(TOP)\ext\lsm1\lsm.h \
   $(TOP)\ext\lsm1\lsmInt.h \
   $(TOP)\ext\lsm1\lsm_ckpt.c \
   $(TOP)\ext\lsm1\lsm_file.c \
   $(TOP)\ext\lsm1\lsm_log.c \
   $(TOP)\ext\lsm1\lsm_main.c \
   $(TOP)\ext\lsm1\lsm_mem.c \
   $(TOP)\ext\lsm1\lsm_mutex.c \
   $(TOP)\ext\lsm1\lsm_shared.c \
   $(TOP)\ext\lsm1\lsm_sorted.c \
   $(TOP)\ext\lsm1\lsm_str.c \
   $(TOP)\ext\lsm1\lsm_tree.c \
   $(TOP)\ext\lsm1\lsm_unix.c \
   $(TOP)\ext\lsm1\lsm_varint.c \
   $(TOP)\ext\lsm1\lsm_vtab.c \
   $(TOP)\ext\lsm1\lsm_win32.c

fts5parse.c:	$(TOP)\ext\fts5\fts5parse.y lemon.exe
	copy $(TOP)\ext\fts5\fts5parse.y .
	del /Q fts5parse.h 2>NUL
	.\lemon.exe $(REQ_FEATURE_FLAGS) $(OPT_FEATURE_FLAGS) $(EXT_FEATURE_FLAGS) $(OPTS) fts5parse.y

fts5parse.h:	fts5parse.c

fts5.c:	$(FTS5_SRC)
	$(TCLSH_CMD) $(TOP)\ext\fts5\tool\mkfts5c.tcl
	copy $(TOP)\ext\fts5\fts5.h .

lsm1.c:	$(LSM1_SRC)
	$(TCLSH_CMD) $(TOP)\ext\lsm1\tool\mklsm1c.tcl
	copy $(TOP)\ext\lsm1\lsm.h .

fts5.lo:	fts5.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) $(NO_WARN) -DSQLITE_CORE -c fts5.c

fts5_ext.lo:	fts5.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) $(NO_WARN) -c fts5.c

fts5.dll:	fts5_ext.lo
	$(LD) $(LDFLAGS) $(LTLINKOPTS) $(LTLIBPATHS) /DLL /OUT:$@ fts5_ext.lo

sqlite3rbu.lo:	$(TOP)\ext\rbu\sqlite3rbu.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) -DSQLITE_CORE -c $(TOP)\ext\rbu\sqlite3rbu.c

# Rules to build the 'testfixture' application.
#
# If using the amalgamation, use sqlite3.c directly to build the test
# fixture.  Otherwise link against libsqlite3.lib.  (This distinction is
# necessary because the test fixture requires non-API symbols which are
# hidden when the library is built via the amalgamation).
#
TESTFIXTURE_FLAGS = -DTCLSH_INIT_PROC=sqlite3TestInit -DSQLITE_TEST=1 -DSQLITE_CRASH_TEST=1
TESTFIXTURE_FLAGS = $(TESTFIXTURE_FLAGS) -DSQLITE_SERVER=1 -DSQLITE_PRIVATE=""
TESTFIXTURE_FLAGS = $(TESTFIXTURE_FLAGS) -DSQLITE_CORE $(NO_WARN)
TESTFIXTURE_FLAGS = $(TESTFIXTURE_FLAGS) -DSQLITE_SERIES_CONSTRAINT_VERIFY=1
TESTFIXTURE_FLAGS = $(TESTFIXTURE_FLAGS) -DSQLITE_DEFAULT_PAGE_SIZE=1024
TESTFIXTURE_FLAGS = $(TESTFIXTURE_FLAGS) -DSQLITE_ENABLE_STMTVTAB
TESTFIXTURE_FLAGS = $(TESTFIXTURE_FLAGS) -DSQLITE_ENABLE_DBPAGE_VTAB
TESTFIXTURE_FLAGS = $(TESTFIXTURE_FLAGS) -DSQLITE_ENABLE_JSON1
TESTFIXTURE_FLAGS = $(TESTFIXTURE_FLAGS) $(TEST_CCONV_OPTS)

TESTFIXTURE_SRC0 = $(TESTEXT) $(TESTSRC2)
TESTFIXTURE_SRC1 = $(TESTEXT) $(SQLITE3C)
!IF $(USE_AMALGAMATION)==0
TESTFIXTURE_SRC = $(TESTSRC) $(TOP)\src\tclsqlite.c $(TESTFIXTURE_SRC0)
!ELSE

	type "$(TCLINCDIR)\tcl.h" | $(TCLSH_CMD) $(TOP)\tool\replace.tcl exact tclDecls.h sqlite_tclDecls.h \
		| $(TCLSH_CMD) $(TOP)\tool\replace.tcl regsub "typedef (.*?)\(Tcl_" "typedef \1 (SQLITE_TCLAPI Tcl_" \
		| $(TCLSH_CMD) $(TOP)\tool\replace.tcl exact "void (*freeProc)" "void (SQLITE_TCLAPI *freeProc)" \
		| $(TCLSH_CMD) $(TOP)\tool\replace.tcl exact "Tcl_HashEntry *(*findProc)" "Tcl_HashEntry *(SQLITE_TCLAPI *findProc)" \
		| $(TCLSH_CMD) $(TOP)\tool\replace.tcl exact "Tcl_HashEntry *(*createProc)" "Tcl_HashEntry *(SQLITE_TCLAPI *createProc)" >> $(SQLITETCLH)
!ENDIF

testfixture.exe:	$(TESTFIXTURE_SRC) $(TESTFIXTURE_DEP) $(SQLITE3H) $(LIBRESOBJS) $(HDR) $(SQLITE_TCL_DEP)
	$(LTLINK) -DSQLITE_NO_SYNC=1 $(TESTFIXTURE_FLAGS) \
		-DBUILD_sqlite -I$(TCLINCDIR) \
		$(TESTFIXTURE_SRC) \
		/link $(LDFLAGS) $(LTLINKOPTS) $(TCLLIBPATHS) $(LTLIBPATHS) $(LIBRESOBJS) $(TCLLIBS) $(LTLIBS) $(TLIBS)

extensiontest:	testfixture.exe testloadext.dll
	@set PATH=$(LIBTCLPATH);$(PATH)
	.\testfixture.exe $(TOP)\test\loadext.test $(TESTOPTS)

fulltest:	$(TESTPROGS) fuzztest
	@set PATH=$(LIBTCLPATH);$(PATH)

	@set PATH=$(LIBTCLPATH);$(PATH)
	.\testfixture.exe $(TOP)\test\veryquick.test $(TESTOPTS)

smoketest:	$(TESTPROGS)
	@set PATH=$(LIBTCLPATH);$(PATH)
	.\testfixture.exe $(TOP)\test\main.test $(TESTOPTS)

sqlite3_analyzer.c:	$(SQLITE3C) $(SQLITE3H) $(TOP)\src\tclsqlite.c $(TOP)\tool\spaceanal.tcl $(TOP)\tool\mkccode.tcl $(TOP)\tool\sqlite3_analyzer.c.in $(SQLITE_TCL_DEP)
	$(TCLSH_CMD) $(TOP)\tool\mkccode.tcl $(TOP)\tool\sqlite3_analyzer.c.in > $@

sqlite3_analyzer.exe:	sqlite3_analyzer.c $(LIBRESOBJS)
	$(LTLINK) $(NO_WARN) -DBUILD_sqlite -I$(TCLINCDIR) sqlite3_analyzer.c \
		/link $(LDFLAGS) $(LTLINKOPTS) $(TCLLIBPATHS) $(LTLIBPATHS) $(LIBRESOBJS) $(TCLLIBS) $(LTLIBS) $(TLIBS)

sqltclsh.c: sqlite3.c $(TOP)\src\tclsqlite.c $(TOP)\tool\sqltclsh.tcl $(TOP)\ext\misc\appendvfs.c $(TOP)\tool\mkccode.tcl $(TOP)\tool\sqltclsh.c.in
	$(TCLSH_CMD) $(TOP)\tool\mkccode.tcl $(TOP)\tool\sqltclsh.c.in >sqltclsh.c

sqltclsh.exe: sqltclsh.c  $(SHELL_CORE_DEP) $(LIBRESOBJS)
	$(LTLINK) $(NO_WARN) -DBUILD_sqlite -I$(TCLINCDIR) sqltclsh.c \
		/link $(LDFLAGS) $(LTLINKOPTS) $(TCLLIBPATHS) $(LTLIBPATHS) $(LIBRESOBJS) $(TCLLIBS) $(LTLIBS) $(TLIBS)

sqlite3_expert.exe: $(SQLITE3C) $(TOP)\ext\expert\sqlite3expert.h $(TOP)\ext\expert\sqlite3expert.c $(TOP)\ext\expert\expert.c
	$(LTLINK) $(NO_WARN)	$(TOP)\ext\expert\sqlite3expert.c $(TOP)\ext\expert\expert.c $(SQLITE3C) $(TLIBS)

CHECKER_DEPS =\
  $(TOP)/tool/mkccode.tcl \
  sqlite3.c \
  $(TOP)/src/tclsqlite.c \
  $(TOP)/ext/repair/sqlite3_checker.tcl \
  $(TOP)/ext/repair/checkindex.c \
  $(TOP)/ext/repair/checkfreelist.c \
  $(TOP)/ext/misc/btreeinfo.c \
  $(TOP)/ext/repair/sqlite3_checker.c.in

sqlite3_checker.c:	$(CHECKER_DEPS)
	$(TCLSH_CMD) $(TOP)\tool\mkccode.tcl $(TOP)\ext\repair\sqlite3_checker.c.in > $@

sqlite3_checker.exe:	sqlite3_checker.c $(LIBRESOBJS)
	$(LTLINK) $(NO_WARN) -DBUILD_sqlite -I$(TCLINCDIR) sqlite3_checker.c \
		/link $(LDFLAGS) $(LTLINKOPTS) $(TCLLIBPATHS) $(LTLIBPATHS) $(LIBRESOBJS) $(TCLLIBS) $(LTLIBS) $(TLIBS)

dbdump.exe:	$(TOP)\ext\misc\dbdump.c $(SQLITE3C) $(SQLITE3H) $(LIBRESOBJS)
	$(LTLINK) $(NO_WARN) -DDBDUMP_STANDALONE $(TOP)\ext\misc\dbdump.c $(SQLITE3C) \
		/link $(LDFLAGS) $(LTLINKOPTS) $(LTLIBPATHS) $(LIBRESOBJS) $(LTLIBS)

testloadext.lo:	$(TOP)\src\test_loadext.c $(SQLITE3H)
	$(LTCOMPILE) $(NO_WARN) -c $(TOP)\src\test_loadext.c

testloadext.dll:	testloadext.lo
	$(LD) $(LDFLAGS) $(LTLINKOPTS) $(LTLIBPATHS) /DLL /OUT:$@ testloadext.lo

showdb.exe:	$(TOP)\tool\showdb.c $(SQLITE3C) $(SQLITE3H)
	$(LTLINK) $(NO_WARN) -DSQLITE_THREADSAFE=0 -DSQLITE_OMIT_LOAD_EXTENSION \

	$(LTLINK) $(NO_WARN) -DSQLITE_THREADSAFE=0 -DSQLITE_OMIT_LOAD_EXTENSION \
		$(TOP)\tool\showjournal.c $(SQLITE3C) /link $(LDFLAGS) $(LTLINKOPTS)

showwal.exe:	$(TOP)\tool\showwal.c $(SQLITE3C) $(SQLITE3H)
	$(LTLINK) $(NO_WARN) -DSQLITE_THREADSAFE=0 -DSQLITE_OMIT_LOAD_EXTENSION \
		$(TOP)\tool\showwal.c $(SQLITE3C) /link $(LDFLAGS) $(LTLINKOPTS)

showshm.exe:	$(TOP)\tool\showshm.c
	$(LTLINK) $(NO_WARN)	$(TOP)\tool\showshm.c /link $(LDFLAGS) $(LTLINKOPTS)

changeset.exe:	$(TOP)\ext\session\changeset.c $(SQLITE3C) $(SQLITE3H)
	$(LTLINK) $(NO_WARN) -DSQLITE_THREADSAFE=0 -DSQLITE_OMIT_LOAD_EXTENSION \
		-DSQLITE_ENABLE_SESSION=1 -DSQLITE_ENABLE_PREUPDATE_HOOK=1 \
		$(TOP)\ext\session\changeset.c $(SQLITE3C) /link $(LDFLAGS) $(LTLINKOPTS)

fts3view.exe:	$(TOP)\ext\fts3\tool\fts3view.c $(SQLITE3C) $(SQLITE3H)
	$(LTLINK) $(NO_WARN) -DSQLITE_THREADSAFE=0 -DSQLITE_OMIT_LOAD_EXTENSION \

	$(LTLINK) $(NO_WARN) $(ST_COMPILE_OPTS) -DSQLITE_OMIT_LOAD_EXTENSION \
		$(TOP)\test\speedtest1.c $(SQLITE3C) /link $(LDFLAGS) $(LTLINKOPTS)

kvtest.exe:	$(TOP)\test\kvtest.c $(SQLITE3C) $(SQLITE3H)
	$(LTLINK) $(NO_WARN) $(KV_COMPILE_OPTS) \
		$(TOP)\test\kvtest.c $(SQLITE3C) /link $(LDFLAGS) $(LTLINKOPTS)




rbu.exe:	$(TOP)\ext\rbu\rbu.c $(TOP)\ext\rbu\sqlite3rbu.c $(SQLITE3C) $(SQLITE3H)
	$(LTLINK) $(NO_WARN) -DSQLITE_ENABLE_RBU \
		$(TOP)\ext\rbu\rbu.c $(SQLITE3C) /link $(LDFLAGS) $(LTLINKOPTS)

LSMDIR=$(TOP)\ext\lsm1
!INCLUDE $(LSMDIR)\Makefile.msc

moreclean:	clean
	del /Q $(SQLITE3C) $(SQLITE3H) 2>NUL
# <</mark>>

clean:
	del /Q *.exp *.lo *.ilk *.lib *.obj *.ncb *.pdb *.sdf *.suo 2>NUL
	del /Q *.bsc *.def *.cod *.da *.bb *.bbg *.vc gmon.out 2>NUL
	del /Q $(SQLITE3EXE) $(SQLITE3DLL) Replace.exe 2>NUL
# <<mark>>
	del /Q sqlite3.c sqlite3.h 2>NUL
	del /Q opcodes.c opcodes.h 2>NUL
	del /Q lemon.* lempar.c parse.* 2>NUL
	del /Q mksourceid.* mkkeywordhash.* keywordhash.h 2>NUL
	del /Q notasharedlib.* 2>NUL
	-rmdir /Q/S .deps 2>NUL
	-rmdir /Q/S .libs 2>NUL
	-rmdir /Q/S tsrc 2>NUL
	del /Q .target_source 2>NUL
	del /Q tclsqlite3.exe $(SQLITETCLH) $(SQLITETCLDECLSH) 2>NUL
	del /Q lsm.dll lsmtest.exe 2>NUL
	del /Q testloadext.dll 2>NUL
	del /Q testfixture.exe test.db 2>NUL
	del /Q LogEst.exe fts3view.exe rollback-test.exe showdb.exe dbdump.exe 2>NUL
	del /Q changeset.exe 2>NUL
	del /Q showjournal.exe showstat4.exe showwal.exe speedtest1.exe 2>NUL
	del /Q mptester.exe wordcount.exe rbu.exe srcck1.exe 2>NUL
	del /Q sqlite3.c sqlite3-*.c 2>NUL
	del /Q sqlite3rc.h 2>NUL
	del /Q shell.c sqlite3ext.h sqlite3session.h 2>NUL
	del /Q sqlite3_analyzer.exe sqlite3_analyzer.c 2>NUL
	del /Q sqlite-*-output.vsix 2>NUL
	del /Q fuzzershell.exe fuzzcheck.exe sqldiff.exe dbhash.exe 2>NUL
	del /Q sqltclsh.* 2>NUL
	del /Q dbfuzz.exe sessionfuzz.exe 2>NUL
	del /Q kvtest.exe ossshell.exe scrub.exe 2>NUL
	del /Q showshm.exe sqlite3_checker.* sqlite3_expert.exe 2>NUL
	del /Q fts5.* fts5parse.* 2>NUL
	del /Q lsm.h lsm1.c 2>NUL
# <</mark>>

<html>

<center>
  <h1> The "server-process-edition" Branch</h1>
</center>

<p>
The "server-process-edition" branch contains two modifications to stock 
SQLite that work together to provide concurrent read/write transactions 
using pessimistic page-level-locking. The system runs in two modes:

<ul>
  <li><p> Single-process mode - where all clients must be within the
          same address space, and 
  <li><p> Multi-process mode - where clients may be distributed between
          multiple OS processes.
</ul>

<p> The system is designed to be most efficient when used with 
<a href="https://www.sqlite.org/pragma.html#pragma_synchronous">
  "PRAGMA synchronous=OFF"</a>, although it does not require this.

<p>
Up to 16 simultaneous read/write transactions controlled by page-level-locking
are possible. Additionally, in single-process mode there may be any number of
read-only transactions started using the "BEGIN READONLY" command. Read-only
transactions do not block read-write transactions, and read-write transactions
do not block read-only transactions. Read-only transactions access a consistent
snapshot of the database - writes committed by other clients after the
transaction has started are never visible to read-only transactions. In
multi-process mode, the "BEGIN READONLY" command is equivalent to a stock
"BEGIN".

<p>
The two features on this branch are:
<ol>
  <li><p> An 
    <a href=#freelist>alternative layout for the database free-page list</a>. 
    This is intended to reduce contention between writers when allocating
    new database pages, either from the free-list or by extending the
    database file.

  <li><p> The <a href=#servermode>"server-mode" extension</a>, which
    provides read/write page-level-locking concurrency and (in
    single-process mode) read-only MVCC concurrency mentioned above.
</ol>


<h2 id=freelist> 1.0 Alternative Free-List Format </h2>

<p>
The alternative free-list format is very similar to the current format. It
differs in the following respects:

<ul>
  <li><p>The "total number of free pages" field in the db header is not
       maintained. It is always set to zero.
  <li><p> Instead of pointing to the first free-list trunk page, the free-list
       pointer in the db header points to a page known as the "free-list node".
  <li><p> The free-list node page contains N pointers to free-lists stored in the
       legacy format (i.e. a linked list of trunk pages each containing
       pointers to many free leaf pages).
</ul>

<p>
This effectively means that a database has N free-lists instead of just one. To
allocate a free page, a writer only needs to lock one such free-list, and so up
to N transactions that allocate new pages may proceed concurrently.

<p>
Allocating pages from the end of the db file still locks out all other
read/write transactions (because it involves writing to page 1, which every
transaction needs to read). To minimize the frequency with which this occurs,
when a page must be allocated from the end of the database file, the file is
extended by 2048 pages. These are distributed equally between 16 free-lists
(children of the free-list node page). Additionally, the first trunk page in
each free list is never reused.  Doing so would require writing to the
free-list node page - effectively an exclusive lock on the entire
page-allocation system.

<p>
The current format used for the free-list can be modified or queried using a
new pragma:

<pre>
  PRAGMA [database.]freelist_format;
  PRAGMA [database.]freelist_format = 1|2;
</pre>

<p>
At present, the free-list format may only be modified when the free-list is
completely empty. Which, as the implementation ensures that a free-list that
uses the alternative format is never completely emptied, effectively precludes
changing the format from 2 (alternative) to 1 (legacy).

<p>
For databases that use the "alternative" free-list format, the read and write
versions in the database header (byte offsets 18 and 19) are set to 3 for
rollback mode or 4 for wal mode (instead of 1 and 2 respectively).

<h2 id=servermode> 2.0 Page level locking - "Server Mode" </h2>

<p>
A database client automatically enters "server mode" if there exists a
<i>directory</i> named "&lt;database&gt;-journal" in the file system alongside
the database file "&lt;database&gt;" There is currently no provision for
creating this directory, although it could be safely done for a database in
rollback mode using something like:

<pre>
  PRAGMA journal_mode = off;
  BEGIN EXCLUSIVE;
    &lt;create directory&gt;
  END;
</pre>

<p> As well as signalling new clients that they should enter server-mode,
creating a directory named "&lt;database&gt;-journal" has the helpful 
side-effect of preventing legacy clients from accessing the database file at
all.

<p> If the VFS is one that takes an exclusive lock on the db file (to 
guarantee that no other process accesses the db file), then the system
automatically enters single-process mode. Otherwise, multi-process mode.

<p> In both single and multi-process modes, page-level-locking is managed
by allocating a fixed-size array of "locking slots". Each locking slot is
32-bits in size. By default, the array contains 262144 (2^18) slots. Pages are
assigned to locking slots using the formula (pgno % 262144) - so pages 1,
262145, 524289 etc. share a single locking slot.

<p> In single-process mode, the array of locking slots is allocated on 
the process heap and access is protected by a mutex. In multi-process mode, it
is created by memory-mapping a file on disk (similar to the *-shm file in
SQLite wal mode) and access is performed using 
<a href="https://en.wikipedia.org/wiki/Compare-and-swap">atomic CAS
  primitives</a> exclusively.

<p> Each time a read/write transaction is opened, the client assumes a client 
id between 0 and 15 for the duration of the transaction. Client ids are unique
at any point in time - concurrently executing transactions must use different
client ids. So there may exist a maximum of 16 concurrent read/write
transactions at any one time.

<p> Read/write transactions in server-mode are similar to regular SQLite
transactions in rollback mode. The most significant differences are that:

<ul>
  <li> <p>Instead of using journal file &lt;database&gt;-journal, server-mode
    clients use &lt;database&gt;-journal/&lt;client-id&gt;-journal. If 
    there are multiple concurrent transactions, each uses a separate 
    journal file.

    <li> <p>No database-wide lock is taken. Instead, individual read and write
    locks are taken on the pages accessed by the transaction.
</ul>

<p> Each locking slot is 32-bits in size. A locking slot may simultaneously
support a single write-lock, up to 16 read-locks from read/write clients, and
(in single process mode) up 1024 read-locks from "BEGIN READONLY" clients.
Locking slot bits are used as follows:

<ul>
  <li> <p> The least-significant 16-bits are used for read-locks taken by
    read/write clients. To take a read-lock, bit &lt;client-id&gt; of the
    locking slot is set.

  <li> <p> The next 5 bytes are used for the write-lock. If no write-lock
    is held on the slot, then this 5 byte integer is set to 0. Otherwise,
    it is set to (<i>C</i> + 1), where <i>C</i> is the &lt;client-id&gt; of
    the client holding the write-lock.

  <li> <p> The next 10 bits contain the total number of read-locks held by
    "BEGIN READONLY" clients on the locking slot. See the section below
    for a description of how these are used.
</ul>

<p> Currently, if a client requests a lock that cannot be granted due to
a conflicting lock, SQLITE_BUSY is returned to the caller and either the
entire transaction or statement transaction must be rolled back. See 
<a href=#problems>Problems and Issues</a> below for more details.

<h3> 2.1 Single-Process Mode </h3>

<p> Single process mode is simpler than multi-process mode because it does
not have to deal with runtime client failure - it is assumed that if one
client fails mid-transaction the entire process crashes. As a result the 
only time hot-journal rollback is required in single-process mode is as
part of startup. The first client to connect to a database in single-process
mode attempts to open and rollback all 16 potential hot journal files.

<p> But, in order to support non-blocking "BEGIN READONLY" transactions, it is
also in some ways more complicated than multi-process mode. "BEGIN READONLY"
support works as follows:

<ul>

  <li> <p>In single-process mode, writers never spill the cache mid-transaction.
    Data is only written to the database as part of committing a transaction.

  <li> <p>As well as writing the contents of overwritten pages out to the journal
    file, a writer in single-process mode also accumulates a list of buffers
    containing the original data for each page overwritten by the current
    transaction in main-memory.

  <li> <p>When a transaction is ready to be committed, a writer obtains a
    transaction-id. Transaction-ids are assigned to writers using a
    monotonically increasing function. The writer then adds all of its "old
    data" buffers to a hash table accessible to all database clients.
    Associated with each hash table entry is the newly assigned transaction-id.
    It then waits (spin-locks) for all "BEGIN READONLY" read-locks to clear on
    all pages that will be written out by the transaction. Following this, it
    commits the transaction as normal (writes out the dirty pages and zeroes
    the journal file header).

  <li> <p>Clients executing "BEGIN READONLY" transactions are not assigned
    a &lt;client-id&gt;. Instead, they are assigned a transaction-id that is 
    either (a) that of the oldest transaction-id belonging to a writer that has
    not yet finished committing, or (b) if there are currently no writers
    committing then the value that will be assigned to the next committer.

  <li> <p>When a "BEGIN READONLY" transaction reads a page, it first checks
    the aforementioned hash table for a suitable entry. A suitable entry
    is one with the right page-number and a transaction-id greater than or
    equal to that of the "BEGIN READONLY" transaction (i.e. one that had not
    finished committing when the BEGIN READONLY transaction started). If such 
    an entry can be found, the client uses the associated data instead of
    reading from the db file. Or, if no such entry is found, the client:
    <ol>
      <li> Increments the number of BEGIN READONLY read-locks on the page.
      <li> Reads the contents of the page from the database file.
      <li> Decrements the number of BEGIN READONLY read-locks on the page.
    </ol>
    <p> The mutex used to protect access to the array of locking slots and
    the shared hash table is relinquished for step 2 above.

  <li> <p>After each transaction is commited in single-process mode, the 
    client searches the hash table for entries that can be discarded. An
    entry can be discarded if it has a transaction-id older than any still
    in use (either by BEGIN READONLY transactions or committers).
</ul>

<h3> 2.2 Multi-Process Mode </h3>

<p> Multi-process mode differs from single-process mode in two important ways:

<ul>
  <li> <p>Individual clients may fail mid-transaction and the system must recover
    from this.

  <li> <p>Partly as a consequence of the above, there are no convenient 
    primitives like mutexes or malloc() with which to build complicated data
    structures like the hash-table used in single-process mode. As a result,
    there is no support for "BEGIN READONLY" transactions in multi-process
    mode.  
</ul>

<p> Unlike single-process mode clients, which may be assigned a different
client-id for each transaction, clients in multi-process mode are assigned a
client-id when they connect to the database and do not relinquish it until
they disconnect. As such, a database in multi-process server-mode supports
at most 16 concurrent client connections.

<p> As well as the array of locking slots, the shared-memory mapping used
by clients in multi-process mode contains 16 "client slots". When a client
connects, it takes a posix WRITE lock on the client slot that corresponds
to its client id. This lock is not released until the client disconnects.
Additionally, whenever a client starts a transaction, it sets the value 
in its client locking slot to 1, and clears it again after the transaction
is concluded.

<p> This assists with handling client failure mid-transaction in two ways:

<ul>
  <li><p> If client A cannot obtain a lock due to a conflicting lock held by
    client B, it can check whether or not client B has failed by attempting a
    WRITE lock on its client locking slot. If successful, then client B must
    have failed and client A may: 
    <ul>
      <li> Roll back client B's journal, and
      <li> By iterating through the entire locking slot array, release all
        locks held by client B when it failed.
    </ul>

  <li><p> When a client first connects and locks its client locking slot, it
    can check whether or not the previous user of the client locking slot failed
    mid-transaction (since if it did, the locking slot value will still be
    non-zero). If it did, the new owner of the client locking slot can release
    any locks and roll back any hot-journal before proceeding.
</ul>

<h3> 2.3 Required VFS Support </h3>

<p> The server-mode extension requires that the VFS support various special
file-control commands. Currently support is limited to the "unix" VFS.

<dl>
  <dt> SQLITE_FCNTL_SERVER_MODE
  <dd><p> This is used by SQLite to query the VFS as to whether the
  connection should use single-process server-mode, multi-process server-mode,
  or continue in legacy mode.

  <p>SQLite invokes this file-control as part of the procedure for detecting a
  hot journal (after it has established that there is a file-system entry named
  &lt;database&gt;-journal and that no other process holds a RESERVED lock).
  If the &lt;database&gt;-journal directory is present in the file-system and
  the current VFS takes an exclusive lock on the database file (i.e. is
  "unix-excl"), then this file-control indicates that the connection should use
  single-process server-mode. Or, if the directory exists but the VFS does not
  take an exclusive lock on the database file, that the connection should use
  multi-proces server-mode. Or, if there is no directory of the required name,
  that the connection should use legacy mode.

  <dt> SQLITE_FCNTL_FILEID
  <dd><p> Return a 128-bit value that uniquely identifies an open file on disk
  from the VFS. This is used to ensure that all connections to the same
  database from within a process use the same shared state, even if they
  connect to the db using different file-system paths.

  <dt> SQLITE_FCNTL_SHMOPEN
  <dd>

  <dt> SQLITE_FCNTL_SHMOPEN2
  <dd>

  <dt> SQLITE_FCNTL_SHMLOCK
  <dd>

  <dt> SQLITE_FCNTL_SHMCLOSE
  <dd>
</dl>


<h2 id=problems> 3.0 Problems and Issues </h2>

<ul>

  <li> <p>Writer starvation might be the biggest issue. How can it be
       prevented?

  <li> <p>Blocking locks of some sort would likely improve things. The issue
       here is deadlock detection.

  <li> <p>The limit of 16 concurrent clients in multi-process mode could be 
       raised to 27 (since the locking-slot bits used for BEGIN READONLY
       locks in single-process mode can be reassigned to support more 
       read/write client read-locks).

</ul>

<h2> 4.0 Performance Test </h2>

<p>
The test uses a single table with the following schema:

<pre>
  CREATE TABLE t1(a INTEGER PRIMARY KEY, b BLOB(16), c BLOB(16), d BLOB(400));
  CREATE INDEX i1 ON t1(b);
  CREATE INDEX i2 ON t1(c);
</pre>

<p>
The database initially contains 5,000,000 rows. Values for column "a" are
between 1 and 5,000,000, inclusive. Other columns are populated with randomly
generated blob values, each 16, 16, and 400 bytes in size, respectively.

<p>
Read/write transactions used by the test take the following form. Each such
transaction modifies approximately 25 pages (5 in the main table and 10 in each
index), not accounting for tree rebalancing operations.

<pre>
  BEGIN;
    REPLACE INTO t1 VALUES(abs(random() % 5000000), randomblob(16), randomblob(16), randomblob(400));
    REPLACE INTO t1 VALUES(abs(random() % 5000000), randomblob(16), randomblob(16), randomblob(400));
    REPLACE INTO t1 VALUES(abs(random() % 5000000), randomblob(16), randomblob(16), randomblob(400));
    REPLACE INTO t1 VALUES(abs(random() % 5000000), randomblob(16), randomblob(16), randomblob(400));
    REPLACE INTO t1 VALUES(abs(random() % 5000000), randomblob(16), randomblob(16), randomblob(400));
  COMMIT;
</pre>

<p>
Read-only transactions are as follows:

<pre>
  BEGIN READONLY;
    SELECT * FROM t1 WHERE a&gt;abs((random()%5000000)) LIMIT 10;
    SELECT * FROM t1 WHERE a&gt;abs((random()%5000000)) LIMIT 10;
    SELECT * FROM t1 WHERE a&gt;abs((random()%5000000)) LIMIT 10;
    SELECT * FROM t1 WHERE a&gt;abs((random()%5000000)) LIMIT 10;
    SELECT * FROM t1 WHERE a&gt;abs((random()%5000000)) LIMIT 10;
  END;
</pre>

<p>
The performance test features one or more clients executing read/write
transactions as fast as possible, and zero or more clients executing read-only
transactions, also as fast as possible. All tests use the "unix-excl" VFS and
all clients execute in a separate thread within the same process. The database
is located on a tmpfs file-system.

<p>
In the table below "rw:" refers to the number of read-write clients, and "ro:"
the number of read-only clients used by the test. The TPS values in brackets
are the number of read-only transactions per second. All other values are 
read-write transactions per second.

<p>
The collision rate (percentage of attempted transactions that failed due to a
page-level locking conflict) in all tests was between 1 and 2%. Failed
transactions are not included in the TPS counts below.

<p>
<table border=1 width=90% align=center>
<!--
  320 jm=persist, rw:1          139675, 135797
  320 jm=wal, rw:1              120995, 118889
  begin-concurrent, rw:1        119438, 117580
  begin-concurrent, rw:2        166923, 166904
  begin-concurrent, rw:3        180432, 172825
  begin-concurrent, rw:2,ro:1   150427(347319),152087(351601) 
  server-mode, rw:1             126592, 126742
  server-mode, rw:2             228317, 227155
  server-mode, rw:3             309712, 306218
  server-mode, rw:2,ro:1        213303(576032),210994(556005) 
-->

  <tr><th> Configuration <th>TPS per client <th> TPS total
  <tr><td> 3.20.0, journal_mode=persist, rw:1, ro:0 <td>6886 <td> 6886
  <tr><td> 3.20.0, journal_mode=wal, rw:1, ro:0 <td>5997 <td> 5997
  <tr><td> begin-concurrent, rw:1, ro:0<td>5925<td> 5925
  <tr><td> begin-concurrent, rw:2, ro:0<td>4172 <td> 8345
  <tr><td> begin-concurrent, rw:3, ro:0<td>2943 <td> 8831
  <tr><td> begin-concurrent, rw:2, ro:1<td>3781 <td> 7562 (17473)
  <tr><td> server-mode, rw:1, ro:0 <td>6333 <td> 6333
  <tr><td> server-mode, rw:2, ro:0<td> 5693 <td> 11386
  <tr><td> server-mode, rw:3, ro:0<td>5132 <td> 15398
  <tr><td> server-mode, rw:2, ro:1<td>5303 <td> 10607 (28300)
</table>

<h1 align="center">SQLite Source Repository</h1>

This repository contains the complete source code for the SQLite database
engine.  Some test scripts are also included.  However, many other test scripts
and most of the documentation are managed separately.

If you are reading this on a Git mirror someplace, you are doing it wrong.
The [official repository](https://www.sqlite.org/src/) is better.  Go there
now.

## Obtaining The Code

SQLite sources are managed using the
[Fossil](https://www.fossil-scm.org/), a distributed version control system
that was specifically designed to support SQLite development.
If you do not want to use Fossil, you can download tarballs or ZIP
archives or [SQLite archives](https://sqlite.org/cli.html#sqlar) as follows:

  *  Lastest trunk check-in as
     [Tarball](https://www.sqlite.org/src/tarball/sqlite.tar.gz),
     [ZIP-archive](https://www.sqlite.org/src/zip/sqlite.zip), or
     [SQLite-archive](https://www.sqlite.org/src/sqlar/sqlite.sqlar).

  *  Latest release as
     [Tarball](https://www.sqlite.org/src/tarball/sqlite.tar.gz?r=release),
     [ZIP-archive](https://www.sqlite.org/src/zip/sqlite.zip?r=release), or
     [SQLite-archive](https://www.sqlite.org/src/sqlar/sqlite.sqlar?r=release).

  *  For other check-ins, substitute an appropriate branch name or
     tag or hash prefix for "release" in the URLs of the previous
     bullet.  Or browse the [timeline](https://www.sqlite.org/src/timeline)
     to locate the check-in desired, click on its information page link,
     then click on the "Tarball" or "ZIP Archive" links on the information
     page.

If you do want to use Fossil to check out the source tree, 
first install Fossil version 2.0 or later.
(Source tarballs and precompiled binaries available
[here](https://www.fossil-scm.org/fossil/uv/download.html).  Fossil is
a stand-alone program.  To install, simply download or build the single 
executable file and put that file someplace on your $PATH.)
Then run commands like this:

        mkdir ~/sqlite
        cd ~/sqlite
        fossil clone https://www.sqlite.org/src sqlite.fossil
        fossil open sqlite.fossil
    

to the "sqlite3.dll" command line above.  When debugging into the SQLite
code, adding the "DEBUG=1" argument to one of the above command lines is
recommended.

SQLite does not require [Tcl](http://www.tcl.tk/) to run, but a Tcl installation
is required by the makefiles (including those for MSVC).  SQLite contains
a lot of generated code and Tcl is used to do much of that code generation.


## Source Code Tour

Most of the core source files are in the **src/** subdirectory.  The
**src/** folder also contains files used to build the "testfixture" test
harness. The names of the source files used by "testfixture" all begin
with "test".
The **src/** also contains the "shell.c" file
which is the main program for the "sqlite3.exe"
[command-line shell](https://sqlite.org/cli.html) and
the "tclsqlite.c" file which implements the
[Tcl bindings](https://sqlite.org/tclsqlite.html) for SQLite.
(Historical note:  SQLite began as a Tcl
extension and only later escaped to the wild as an independent library.)

Test scripts and programs are found in the **test/** subdirectory.
Addtional test code is found in other source repositories.
See [How SQLite Is Tested](http://www.sqlite.org/testing.html) for
additional information.


The **ext/** subdirectory contains code for extensions.  The
Full-text search engine is in **ext/fts3**.  The R-Tree engine is in
**ext/rtree**.  The **ext/misc** subdirectory contains a number of
smaller, single-file extensions, such as a REGEXP operator.

The **tool/** subdirectory contains various scripts and programs used

The "target_source" make target will create a subdirectory "tsrc/" and
fill it with all the source files needed to build SQLite, both
manually-edited files and automatically-generated files.

The SQLite interface is defined by the **sqlite3.h** header file, which is
generated from src/sqlite.h.in, ./manifest.uuid, and ./VERSION.  The
[Tcl script](http://www.tcl.tk) at tool/mksqlite3h.tcl does the conversion.
The manifest.uuid file contains the SHA3 hash of the particular check-in
and is used to generate the SQLITE\_SOURCE\_ID macro.  The VERSION file
contains the current SQLite version number.  The sqlite3.h header is really
just a copy of src/sqlite.h.in with the source-id and version number inserted
at just the right spots. Note that comment text in the sqlite3.h file is
used to generate much of the SQLite API documentation.  The Tcl scripts
used to generate that documentation are in a separate source repository.

The SQL language parser is **parse.c** which is generate from a grammar in
the src/parse.y file.  The conversion of "parse.y" into "parse.c" is done
by the [lemon](./doc/lemon.html) LALR(1) parser generator.  The source code
for lemon is at tool/lemon.c.  Lemon uses the tool/lempar.c file as a
template for generating its parser.


Lemon also generates the **parse.h** header file, at the same time it
generates parse.c. But the parse.h header file is
modified further (to add additional symbols) using the ./addopcodes.tcl
Tcl script.

The **opcodes.h** header file contains macros that define the numbers
corresponding to opcodes in the "VDBE" virtual machine.  The opcodes.h
file is generated by the scanning the src/vdbe.c source file.  The
Tcl script at ./mkopcodeh.tcl does this scan and generates opcodes.h.
A second Tcl script, ./mkopcodec.tcl, then scans opcodes.h to generate
the **opcodes.c** source file, which contains a reverse mapping from
opcode-number to opcode-name that is used for EXPLAIN output.

The **keywordhash.h** header file contains the definition of a hash table
that maps SQL language keywords (ex: "CREATE", "SELECT", "INDEX", etc.) into
the numeric codes used by the parse.c parser.  The keywordhash.h file is
generated by a C-language program at tool mkkeywordhash.c.

The **pragma.h** header file contains various definitions used to parse
and implement the PRAGMA statements.  The header is generated by a
script **tool/mkpragmatab.tcl**. If you want to add a new PRAGMA, edit
the **tool/mkpragmatab.tcl** file to insert the information needed by the
parser for your new PRAGMA, then run the script to regenerate the
**pragma.h** header file.

### The Amalgamation

All of the individual C source code and header files (both manually-edited
and automatically-generated) can be combined into a single big source file
**sqlite3.c** called "the amalgamation".  The amalgamation is the recommended
way of using SQLite in a larger application.  Combining all individual
source code files into a single big source code file allows the C compiler
to perform more cross-procedure analysis and generate better code.  SQLite
runs about 5% faster when compiled from the amalgamation versus when compiled
from individual source files.

The amalgamation is generated from the tool/mksqlite3c.tcl Tcl script.
First, all of the individual source files must be gathered into the tsrc/
subdirectory (using the equivalent of "make target_source") then the
tool/mksqlite3c.tcl script is run to copy them all together in just the
right order while resolving internal "#include" references.

The amalgamation source file is more than 200K lines long.  Some symbolic
debuggers (most notably MSVC) are unable to deal with files longer than 64K
lines.  To work around this, a separate Tcl script, tool/split-sqlite3c.tcl,
can be run on the amalgamation to break it up into a single small C file
called **sqlite3-all.c** that does #include on about seven other files
named **sqlite3-1.c**, **sqlite3-2.c**, ..., **sqlite3-7.c**.  In this way,
all of the source code is contained within a single translation unit so
that the compiler can do extra cross-procedure optimization, but no
individual source file exceeds 32K lines in length.

## How It All Fits Together

SQLite is modular in design.
See the [architectural description](http://www.sqlite.org/arch.html)
for details. Other documents that are useful in
(helping to understand how SQLite works include the
[file format](http://www.sqlite.org/fileformat2.html) description,
the [virtual machine](http://www.sqlite.org/opcode.html) that runs
prepared statements, the description of
[how transactions work](http://www.sqlite.org/atomiccommit.html), and
the [overview of the query planner](http://www.sqlite.org/optoverview.html).

Years of effort have gone into optimizating SQLite, both
for small size and high performance.  And optimizations tend to result in
complex code.  So there is a lot of complexity in the current SQLite
implementation.  It will not be the easiest library in the world to hack.

Key files:

  *  **sqlite.h.in** - This file defines the public interface to the SQLite
     library.  Readers will need to be familiar with this interface before
     trying to understand how the library works internally.

  *  **sqliteInt.h** - this header file defines many of the data objects
     used internally by SQLite.  In addition to "sqliteInt.h", some
     subsystems have their own header files.

  *  **parse.y** - This file describes the LALR(1) grammar that SQLite uses
     to parse SQL statements, and the actions that are taken at each step
     in the parsing process.

  *  **vdbe.c** - This file implements the virtual machine that runs
     prepared statements.  There are various helper files whose names
     begin with "vdbe".  The VDBE has access to the vdbeInt.h header file
     which defines internal data objects.  The rest of SQLite interacts
     with the VDBE through an interface defined by vdbe.h.

  *  **where.c** - This file (together with its helper files named
     by "where*.c") analyzes the WHERE clause and generates
     virtual machine code to run queries efficiently.  This file is
     sometimes called the "query optimizer".  It has its own private
     header file, whereInt.h, that defines data objects used internally.

  *  **btree.c** - This file contains the implementation of the B-Tree
     storage engine used by SQLite.  The interface to the rest of the system
     is defined by "btree.h".  The "btreeInt.h" header defines objects
     used internally by btree.c and not published to the rest of the system.

  *  **pager.c** - This file contains the "pager" implementation, the
     module that implements transactions.  The "pager.h" header file
     defines the interface between pager.c and the rest of the system.

  *  **os_unix.c** and **os_win.c** - These two files implement the interface
     between SQLite and the underlying operating system using the run-time
     pluggable VFS interface.

  *  **shell.c.in** - This file is not part of the core SQLite library.  This
     is the file that, when linked against sqlite3.a, generates the
     "sqlite3.exe" command-line shell.  The "shell.c.in" file is transformed
     into "shell.c" as part of the build process.

  *  **tclsqlite.c** - This file implements the Tcl bindings for SQLite.  It
     is not part of the core SQLite library.  But as most of the tests in this
     repository are written in Tcl, the Tcl language bindings are important.

  *  **test*.c** - Files in the src/ folder that begin with "test" go into
     building the "testfixture.exe" program.  The testfixture.exe program is
     an enhanced Tcl shell.  The testfixture.exe program runs scripts in the
     test/ folder to validate the core SQLite code.  The testfixture program
     (and some other test programs too) is build and run when you type
     "make test".

  *  **ext/misc/json1.c** - This file implements the various JSON functions
     that are build into SQLite.

There are many other source files.  Each has a succinct header comment that
describes its purpose and role within the larger system.


## Contacts

The main SQLite webpage is [http://www.sqlite.org/](http://www.sqlite.org/)
with geographically distributed backups at
[http://www2.sqlite.org/](http://www2.sqlite.org) and
[http://www3.sqlite.org/](http://www3.sqlite.org).

3.23.0

AM_CFLAGS = @THREADSAFE_FLAGS@ @DYNAMIC_EXTENSION_FLAGS@ @FTS5_FLAGS@ @JSON1_FLAGS@ @ZLIB_FLAGS@ @SESSION_FLAGS@ -DSQLITE_ENABLE_FTS3 -DSQLITE_ENABLE_RTREE

lib_LTLIBRARIES = libsqlite3.la
libsqlite3_la_SOURCES = sqlite3.c
libsqlite3_la_LDFLAGS = -no-undefined -version-info 8:6:8

bin_PROGRAMS = sqlite3
sqlite3_SOURCES = shell.c sqlite3.h
EXTRA_sqlite3_SOURCES = sqlite3.c
sqlite3_LDADD = @EXTRA_SHELL_OBJ@ @READLINE_LIBS@
sqlite3_DEPENDENCIES = @EXTRA_SHELL_OBJ@
sqlite3_CFLAGS = $(AM_CFLAGS) -DSQLITE_ENABLE_EXPLAIN_COMMENTS -DSQLITE_ENABLE_DBPAGE_VTAB -DSQLITE_ENABLE_STMTVTAB -DSQLITE_ENABLE_DBSTAT_VTAB $(SHELL_CFLAGS)

include_HEADERS = sqlite3.h sqlite3ext.h

EXTRA_DIST = sqlite3.1 tea Makefile.msc sqlite3.rc README.txt Replace.cs
pkgconfigdir = ${libdir}/pkgconfig
pkgconfig_DATA = sqlite3.pc

#
TOP = .


# Set this non-0 to enable full warnings (-W4, etc) when compiling.
#
!IFNDEF USE_FULLWARN
USE_FULLWARN = 1
!ENDIF

# Set this non-0 to enable treating warnings as errors (-WX, etc) when
# compiling.
#
!IFNDEF USE_FATAL_WARN
USE_FATAL_WARN = 0

!IFNDEF SHELL_CORE_DEP
!IF $(DYNAMIC_SHELL)!=0 || $(FOR_WIN10)!=0
SHELL_CORE_DEP = $(SQLITE3DLL)
!ELSE
SHELL_CORE_DEP =
!ENDIF
!ENDIF


# This is the core library that the shell executable should link with.
#
!IFNDEF SHELL_CORE_LIB
!IF $(DYNAMIC_SHELL)!=0 || $(FOR_WIN10)!=0
SHELL_CORE_LIB = $(SQLITE3LIB)
!ELSE

LTRCOMPILE = $(RCC) -r
LTLIB = lib.exe
LTLINK = $(TCC) -Fe$@

# If requested, link to the RPCRT4 library.
#
!IF $(USE_RPCRT4_LIB)!=0
LTLIBS = $(LTLIBS) rpcrt4.lib
!ENDIF

# If a platform was set, force the linker to target that.
# Note that the vcvars*.bat family of batch files typically
# set this for you.  Otherwise, the linker will attempt
# to deduce the binary type based on the object files.
!IFDEF PLATFORM

!ENDIF


# Additional compiler options for the shell.  These are only effective
# when the shell is not being dynamically linked.
#
!IF $(DYNAMIC_SHELL)==0 && $(FOR_WIN10)==0
SHELL_COMPILE_OPTS = $(SHELL_COMPILE_OPTS) -DSQLITE_ENABLE_JSON1 -DSQLITE_ENABLE_FTS4 -DSQLITE_ENABLE_EXPLAIN_COMMENTS -DSQLITE_ENABLE_STMTVTAB
SHELL_COMPILE_OPTS = $(SHELL_COMPILE_OPTS) -DSQLITE_ENABLE_DBPAGE_VTAB -DSQLITE_ENABLE_DBSTAT_VTAB
SHELL_COMPILE_OPTS = $(SHELL_COMPILE_OPTS) -DSQLITE_ENABLE_OFFSET_SQL_FUNC -DSQLITE_INTROSPECTION_PRAGMAS
SHELL_COMPILE_OPTS = $(SHELL_COMPILE_OPTS) -DSQLITE_ENABLE_RTREE
!ENDIF


# This is the default Makefile target.  The objects listed here
# are what get build when you type just "make" with no arguments.
#
core:	dll shell

# Targets that require the Tcl library.
#
tcl:	$(ALL_TCL_TARGETS)

# This Makefile target builds all of the standard binaries.
#
all:	core tcl

# Dynamic link library section.
#
dll:	$(SQLITE3DLL)

# Shell executable.
#
shell:	$(SQLITE3EXE)


$(SQLITE3DLL):	$(LIBOBJ) $(LIBRESOBJS) $(CORE_LINK_DEP)
	$(LD) $(LDFLAGS) $(LTLINKOPTS) $(LTLIBPATHS) /DLL $(CORE_LINK_OPTS) /OUT:$@ $(LIBOBJ) $(LIBRESOBJS) $(LTLIBS) $(TLIBS)

Replace.exe:
	$(CSC) /target:exe $(TOP)\Replace.cs

sqlite3.def:	Replace.exe $(LIBOBJ)
	echo EXPORTS > sqlite3.def
	dumpbin /all $(LIBOBJ) \
		| .\Replace.exe "^\s+/EXPORT:_?(sqlite3(?:session|changeset|changegroup)?_[^@,]*)(?:@\d+|,DATA)?$$" $$1 true \
		| sort >> sqlite3.def

$(SQLITE3EXE):	shell.c $(SHELL_CORE_DEP) $(LIBRESOBJS) $(SHELL_CORE_SRC) $(SQLITE3H)
	$(LTLINK) $(SHELL_COMPILE_OPTS) $(READLINE_FLAGS) shell.c $(SHELL_CORE_SRC) \
		/link $(SQLITE3EXEPDB) $(LDFLAGS) $(LTLINKOPTS) $(SHELL_LINK_OPTS) $(LTLIBPATHS) $(LIBRESOBJS) $(LIBREADLINE) $(LTLIBS) $(TLIBS)


# Rule to build the amalgamation
#
sqlite3.lo:	$(SQLITE3C)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) -c $(SQLITE3C)


# Rule to build the Win32 resources object file.
#
!IF $(USE_RC)!=0
_HASHCHAR=^#
!IF ![echo !IFNDEF VERSION > rcver.vc] && \
    ![for /F "delims=" %V in ('type "$(SQLITE3H)" ^| "%SystemRoot%\System32\find.exe" "$(_HASHCHAR)define SQLITE_VERSION "') do (echo VERSION = ^^%V >> rcver.vc)] && \
    ![echo !ENDIF >> rcver.vc]
!INCLUDE rcver.vc
!ENDIF

RESOURCE_VERSION = $(VERSION:^#=)
RESOURCE_VERSION = $(RESOURCE_VERSION:define=)
RESOURCE_VERSION = $(RESOURCE_VERSION:SQLITE_VERSION=)

#   --enable-static-shell
#   --enable-dynamic-extensions
#

AC_PREREQ(2.61)
AC_INIT(sqlite, --SQLITE-VERSION--, http://www.sqlite.org)
AC_CONFIG_SRCDIR([sqlite3.c])
AC_CONFIG_AUX_DIR([.])

# Use automake.
AM_INIT_AUTOMAKE([foreign])

AC_SYS_LARGEFILE

# Check for required programs.

else
  EXTRA_SHELL_OBJ=libsqlite3.la
fi
AC_SUBST(EXTRA_SHELL_OBJ)
#-----------------------------------------------------------------------

AC_CHECK_FUNCS(posix_fallocate)
AC_CHECK_HEADERS(zlib.h,[
  AC_SEARCH_LIBS(deflate,z,[ZLIB_FLAGS="-DSQLITE_HAVE_ZLIB"])
])
AC_SUBST(ZLIB_FLAGS)

AC_SEARCH_LIBS(system,,,[SHELL_CFLAGS="-DSQLITE_NOHAVE_SYSTEM"])
AC_SUBST(SHELL_CFLAGS)

#-----------------------------------------------------------------------
# UPDATE: Maybe it's better if users just set CFLAGS before invoking
# configure. This option doesn't really add much...
#
#   --enable-tempstore
#

#! /bin/sh
# Guess values for system-dependent variables and create Makefiles.
# Generated by GNU Autoconf 2.69 for sqlite 3.23.0.
#
#
# Copyright (C) 1992-1996, 1998-2012 Free Software Foundation, Inc.
#
#
# This configure script is free software; the Free Software Foundation
# gives unlimited permission to copy, distribute and modify it.

subdirs=
MFLAGS=
MAKEFLAGS=

# Identity of this package.
PACKAGE_NAME='sqlite'
PACKAGE_TARNAME='sqlite'
PACKAGE_VERSION='3.23.0'
PACKAGE_STRING='sqlite 3.23.0'
PACKAGE_BUGREPORT=''
PACKAGE_URL=''

# Factoring default headers for most tests.
ac_includes_default="\
#include <stdio.h>
#ifdef HAVE_SYS_TYPES_H

#endif"

ac_subst_vars='LTLIBOBJS
LIBOBJS
BUILD_CFLAGS
USE_GCOV
OPT_FEATURE_FLAGS
HAVE_ZLIB
USE_AMALGAMATION
TARGET_DEBUG
TARGET_HAVE_EDITLINE
TARGET_HAVE_READLINE
TARGET_READLINE_INC
TARGET_READLINE_LIBS
HAVE_TCL

enable_load_extension
enable_memsys5
enable_memsys3
enable_fts3
enable_fts4
enable_fts5
enable_json1
enable_update_limit
enable_rtree
enable_session
enable_gcov
'
      ac_precious_vars='build_alias
host_alias
target_alias

#
# Report the --help message.
#
if test "$ac_init_help" = "long"; then
  # Omit some internal or obsolete options to make the list less imposing.
  # This message is too long to be a string in the A/UX 3.1 sh.
  cat <<_ACEOF
\`configure' configures sqlite 3.23.0 to adapt to many kinds of systems.

Usage: $0 [OPTION]... [VAR=VALUE]...

To assign environment variables (e.g., CC, CFLAGS...), specify them as
VAR=VALUE.  See below for descriptions of some of the useful variables.

Defaults for the options are specified in brackets.

  --build=BUILD     configure for building on BUILD [guessed]
  --host=HOST       cross-compile to build programs to run on HOST [BUILD]
_ACEOF
fi

if test -n "$ac_init_help"; then
  case $ac_init_help in
     short | recursive ) echo "Configuration of sqlite 3.23.0:";;
   esac
  cat <<\_ACEOF

Optional Features:
  --disable-option-checking  ignore unrecognized --enable/--with options
  --disable-FEATURE       do not include FEATURE (same as --enable-FEATURE=no)
  --enable-FEATURE[=ARG]  include FEATURE [ARG=yes]

                          Disable loading of external extensions
  --enable-memsys5        Enable MEMSYS5
  --enable-memsys3        Enable MEMSYS3
  --enable-fts3           Enable the FTS3 extension
  --enable-fts4           Enable the FTS4 extension
  --enable-fts5           Enable the FTS5 extension
  --enable-json1          Enable the JSON1 extension
  --enable-update-limit   Enable the UPDATE/DELETE LIMIT clause
  --enable-rtree          Enable the RTREE extension
  --enable-session        Enable the SESSION extension
  --enable-gcov           Enable coverage testing using gcov

Optional Packages:
  --with-PACKAGE[=ARG]    use PACKAGE [ARG=yes]
  --without-PACKAGE       do not use PACKAGE (same as --with-PACKAGE=no)

    cd "$ac_pwd" || { ac_status=$?; break; }
  done
fi

test -n "$ac_init_help" && exit $ac_status
if $ac_init_version; then
  cat <<\_ACEOF
sqlite configure 3.23.0
generated by GNU Autoconf 2.69

Copyright (C) 2012 Free Software Foundation, Inc.
This configure script is free software; the Free Software Foundation
gives unlimited permission to copy, distribute and modify it.
_ACEOF
  exit

  eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno

} # ac_fn_c_check_header_mongrel
cat >config.log <<_ACEOF
This file contains any messages produced by compilers while
running configure, to aid debugging if configure makes a mistake.

It was created by sqlite $as_me 3.23.0, which was
generated by GNU Autoconf 2.69.  Invocation command line was

  $ $0 $@

_ACEOF
exec 5>>config.log
{

{ $as_echo "$as_me:${as_lineno-$LINENO}: checking the name lister ($NM) interface" >&5
$as_echo_n "checking the name lister ($NM) interface... " >&6; }
if ${lt_cv_nm_interface+:} false; then :
  $as_echo_n "(cached) " >&6
else
  lt_cv_nm_interface="BSD nm"
  echo "int some_variable = 0;" > conftest.$ac_ext
  (eval echo "\"\$as_me:3935: $ac_compile\"" >&5)
  (eval "$ac_compile" 2>conftest.err)
  cat conftest.err >&5
  (eval echo "\"\$as_me:3938: $NM \\\"conftest.$ac_objext\\\"\"" >&5)
  (eval "$NM \"conftest.$ac_objext\"" 2>conftest.err > conftest.out)
  cat conftest.err >&5
  (eval echo "\"\$as_me:3941: output\"" >&5)
  cat conftest.out >&5
  if $GREP 'External.*some_variable' conftest.out > /dev/null; then
    lt_cv_nm_interface="MS dumpbin"
  fi
  rm -f conftest*
fi
{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $lt_cv_nm_interface" >&5

	;;
    esac
  fi
  rm -rf conftest*
  ;;
*-*-irix6*)
  # Find out which ABI we are using.
  echo '#line 5147 "configure"' > conftest.$ac_ext
  if { { eval echo "\"\$as_me\":${as_lineno-$LINENO}: \"$ac_compile\""; } >&5
  (eval $ac_compile) 2>&5
  ac_status=$?
  $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
  test $ac_status = 0; }; then
    if test "$lt_cv_prog_gnu_ld" = yes; then
      case `/usr/bin/file conftest.$ac_objext` in

   # Note that $ac_compile itself does not contain backslashes and begins
   # with a dollar sign (not a hyphen), so the echo should work correctly.
   # The option is referenced via a variable to avoid confusing sed.
   lt_compile=`echo "$ac_compile" | $SED \
   -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
   -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
   -e 's:$: $lt_compiler_flag:'`
   (eval echo "\"\$as_me:6672: $lt_compile\"" >&5)
   (eval "$lt_compile" 2>conftest.err)
   ac_status=$?
   cat conftest.err >&5
   echo "$as_me:6676: \$? = $ac_status" >&5
   if (exit $ac_status) && test -s "$ac_outfile"; then
     # The compiler can only warn and ignore the option if not recognized
     # So say no if there are warnings other than the usual output.
     $ECHO "X$_lt_compiler_boilerplate" | $Xsed -e '/^$/d' >conftest.exp
     $SED '/^$/d; /^ *+/d' conftest.err >conftest.er2
     if test ! -s conftest.er2 || diff conftest.exp conftest.er2 >/dev/null; then
       lt_cv_prog_compiler_rtti_exceptions=yes

   # Note that $ac_compile itself does not contain backslashes and begins
   # with a dollar sign (not a hyphen), so the echo should work correctly.
   # The option is referenced via a variable to avoid confusing sed.
   lt_compile=`echo "$ac_compile" | $SED \
   -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
   -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
   -e 's:$: $lt_compiler_flag:'`
   (eval echo "\"\$as_me:7011: $lt_compile\"" >&5)
   (eval "$lt_compile" 2>conftest.err)
   ac_status=$?
   cat conftest.err >&5
   echo "$as_me:7015: \$? = $ac_status" >&5
   if (exit $ac_status) && test -s "$ac_outfile"; then
     # The compiler can only warn and ignore the option if not recognized
     # So say no if there are warnings other than the usual output.
     $ECHO "X$_lt_compiler_boilerplate" | $Xsed -e '/^$/d' >conftest.exp
     $SED '/^$/d; /^ *+/d' conftest.err >conftest.er2
     if test ! -s conftest.er2 || diff conftest.exp conftest.er2 >/dev/null; then
       lt_cv_prog_compiler_pic_works=yes

   # (2) before a word containing "conftest.", or (3) at the end.
   # Note that $ac_compile itself does not contain backslashes and begins
   # with a dollar sign (not a hyphen), so the echo should work correctly.
   lt_compile=`echo "$ac_compile" | $SED \
   -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
   -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
   -e 's:$: $lt_compiler_flag:'`
   (eval echo "\"\$as_me:7116: $lt_compile\"" >&5)
   (eval "$lt_compile" 2>out/conftest.err)
   ac_status=$?
   cat out/conftest.err >&5
   echo "$as_me:7120: \$? = $ac_status" >&5
   if (exit $ac_status) && test -s out/conftest2.$ac_objext
   then
     # The compiler can only warn and ignore the option if not recognized
     # So say no if there are warnings
     $ECHO "X$_lt_compiler_boilerplate" | $Xsed -e '/^$/d' > out/conftest.exp
     $SED '/^$/d; /^ *+/d' out/conftest.err >out/conftest.er2
     if test ! -s out/conftest.er2 || diff out/conftest.exp out/conftest.er2 >/dev/null; then

   # (2) before a word containing "conftest.", or (3) at the end.
   # Note that $ac_compile itself does not contain backslashes and begins
   # with a dollar sign (not a hyphen), so the echo should work correctly.
   lt_compile=`echo "$ac_compile" | $SED \
   -e 's:.*FLAGS}\{0,1\} :&$lt_compiler_flag :; t' \
   -e 's: [^ ]*conftest\.: $lt_compiler_flag&:; t' \
   -e 's:$: $lt_compiler_flag:'`
   (eval echo "\"\$as_me:7171: $lt_compile\"" >&5)
   (eval "$lt_compile" 2>out/conftest.err)
   ac_status=$?
   cat out/conftest.err >&5
   echo "$as_me:7175: \$? = $ac_status" >&5
   if (exit $ac_status) && test -s out/conftest2.$ac_objext
   then
     # The compiler can only warn and ignore the option if not recognized
     # So say no if there are warnings
     $ECHO "X$_lt_compiler_boilerplate" | $Xsed -e '/^$/d' > out/conftest.exp
     $SED '/^$/d; /^ *+/d' out/conftest.err >out/conftest.er2
     if test ! -s out/conftest.er2 || diff out/conftest.exp out/conftest.er2 >/dev/null; then

else
  	  if test "$cross_compiling" = yes; then :
  lt_cv_dlopen_self=cross
else
  lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
  lt_status=$lt_dlunknown
  cat > conftest.$ac_ext <<_LT_EOF
#line 9551 "configure"
#include "confdefs.h"

#if HAVE_DLFCN_H
#include <dlfcn.h>
#endif

#include <stdio.h>

else
  	  if test "$cross_compiling" = yes; then :
  lt_cv_dlopen_self_static=cross
else
  lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
  lt_status=$lt_dlunknown
  cat > conftest.$ac_ext <<_LT_EOF
#line 9647 "configure"
#include "confdefs.h"

#if HAVE_DLFCN_H
#include <dlfcn.h>
#endif

#include <stdio.h>

USE_AMALGAMATION=1

#########
# See whether we can run specific tclsh versions known to work well;
# if not, then we fall back to plain tclsh.
# TODO: try other versions before falling back?
#
for ac_prog in tclsh8.7 tclsh8.6 tclsh8.5 tclsh
do
  # Extract the first word of "$ac_prog", so it can be a program name with args.
set dummy $ac_prog; ac_word=$2
{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
$as_echo_n "checking for $ac_word... " >&6; }
if ${ac_cv_prog_TCLSH_CMD+:} false; then :
  $as_echo_n "(cached) " >&6

  use_amalgamation=yes
fi

if test "${use_amalgamation}" != "yes" ; then
  USE_AMALGAMATION=0
fi


#########
# Look for zlib.  Only needed by extensions and by the sqlite3.exe shell
for ac_header in zlib.h
do :
  ac_fn_c_check_header_mongrel "$LINENO" "zlib.h" "ac_cv_header_zlib_h" "$ac_includes_default"
if test "x$ac_cv_header_zlib_h" = xyes; then :
  cat >>confdefs.h <<_ACEOF
#define HAVE_ZLIB_H 1
_ACEOF

fi

done

{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing deflate" >&5
$as_echo_n "checking for library containing deflate... " >&6; }
if ${ac_cv_search_deflate+:} false; then :
  $as_echo_n "(cached) " >&6
else
  ac_func_search_save_LIBS=$LIBS
cat confdefs.h - <<_ACEOF >conftest.$ac_ext
/* end confdefs.h.  */

/* Override any GCC internal prototype to avoid an error.
   Use char because int might match the return type of a GCC
   builtin and then its argument prototype would still apply.  */
#ifdef __cplusplus
extern "C"
#endif
char deflate ();
int
main ()
{
return deflate ();
  ;
  return 0;
}
_ACEOF
for ac_lib in '' z; do
  if test -z "$ac_lib"; then
    ac_res="none required"
  else
    ac_res=-l$ac_lib
    LIBS="-l$ac_lib  $ac_func_search_save_LIBS"
  fi
  if ac_fn_c_try_link "$LINENO"; then :
  ac_cv_search_deflate=$ac_res
fi
rm -f core conftest.err conftest.$ac_objext \
    conftest$ac_exeext
  if ${ac_cv_search_deflate+:} false; then :
  break
fi
done
if ${ac_cv_search_deflate+:} false; then :

else
  ac_cv_search_deflate=no
fi
rm conftest.$ac_ext
LIBS=$ac_func_search_save_LIBS
fi
{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ac_cv_search_deflate" >&5
$as_echo "$ac_cv_search_deflate" >&6; }
ac_res=$ac_cv_search_deflate
if test "$ac_res" != no; then :
  test "$ac_res" = "none required" || LIBS="$ac_res $LIBS"
  HAVE_ZLIB="-DSQLITE_HAVE_ZLIB=1"
else
  HAVE_ZLIB=""
fi



#########
# See whether we should allow loadable extensions
# Check whether --enable-load-extension was given.
if test "${enable_load_extension+set}" = set; then :
  enableval=$enable_load_extension; use_loadextension=$enableval
else

else
  enable_memsys5=no
fi

{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether to support MEMSYS5" >&5
$as_echo_n "checking whether to support MEMSYS5... " >&6; }
if test "${enable_memsys5}" = "yes"; then
  OPT_FEATURE_FLAGS="${OPT_FEATURE_FLAGS} -DSQLITE_ENABLE_MEMSYS5"
  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
$as_echo "yes" >&6; }
else
  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
$as_echo "no" >&6; }
fi
# Check whether --enable-memsys3 was given.
if test "${enable_memsys3+set}" = set; then :
  enableval=$enable_memsys3; enable_memsys3=yes
else
  enable_memsys3=no
fi

{ $as_echo "$as_me:${as_lineno-$LINENO}: checking whether to support MEMSYS3" >&5
$as_echo_n "checking whether to support MEMSYS3... " >&6; }
if test "${enable_memsys3}" = "yes" -a "${enable_memsys5}" = "no"; then
  OPT_FEATURE_FLAGS="${OPT_FEATURE_FLAGS} -DSQLITE_ENABLE_MEMSYS3"
  { $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
$as_echo "yes" >&6; }
else
  { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
$as_echo "no" >&6; }
fi

#########
# See whether we should enable Full Text Search extensions
# Check whether --enable-fts3 was given.
if test "${enable_fts3+set}" = set; then :
  enableval=$enable_fts3; enable_fts3=yes
else
  enable_fts3=no
fi

if test "${enable_fts3}" = "yes" ; then
  OPT_FEATURE_FLAGS="${OPT_FEATURE_FLAGS} -DSQLITE_ENABLE_FTS3"
fi
# Check whether --enable-fts4 was given.
if test "${enable_fts4+set}" = set; then :
  enableval=$enable_fts4; enable_fts4=yes
else
  enable_fts4=no
fi

if test "${enable_fts4}" = "yes" ; then
  OPT_FEATURE_FLAGS="${OPT_FEATURE_FLAGS} -DSQLITE_ENABLE_FTS4"
  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing log" >&5
$as_echo_n "checking for library containing log... " >&6; }
if ${ac_cv_search_log+:} false; then :
  $as_echo_n "(cached) " >&6
else
  ac_func_search_save_LIBS=$LIBS
cat confdefs.h - <<_ACEOF >conftest.$ac_ext

if test "${enable_fts5+set}" = set; then :
  enableval=$enable_fts5; enable_fts5=yes
else
  enable_fts5=no
fi

if test "${enable_fts5}" = "yes" ; then
  OPT_FEATURE_FLAGS="${OPT_FEATURE_FLAGS} -DSQLITE_ENABLE_FTS5"
  { $as_echo "$as_me:${as_lineno-$LINENO}: checking for library containing log" >&5
$as_echo_n "checking for library containing log... " >&6; }
if ${ac_cv_search_log+:} false; then :
  $as_echo_n "(cached) " >&6
else
  ac_func_search_save_LIBS=$LIBS
cat confdefs.h - <<_ACEOF >conftest.$ac_ext

if test "${enable_json1+set}" = set; then :
  enableval=$enable_json1; enable_json1=yes
else
  enable_json1=no
fi

if test "${enable_json1}" = "yes" ; then
  OPT_FEATURE_FLAGS="${OPT_FEATURE_FLAGS} -DSQLITE_ENABLE_JSON1"
fi

#########
# See whether we should enable the LIMIT clause on UPDATE and DELETE
# statements.
# Check whether --enable-update-limit was given.
if test "${enable_update_limit+set}" = set; then :
  enableval=$enable_update_limit; enable_udlimit=yes
else
  enable_udlimit=no
fi

if test "${enable_udlimit}" = "yes" ; then
  OPT_FEATURE_FLAGS="${OPT_FEATURE_FLAGS} -DSQLITE_ENABLE_UPDATE_DELETE_LIMIT"
fi

#########
# See whether we should enable RTREE
# Check whether --enable-rtree was given.
if test "${enable_rtree+set}" = set; then :
  enableval=$enable_rtree; enable_rtree=yes
else
  enable_rtree=no
fi

if test "${enable_rtree}" = "yes" ; then
  OPT_FEATURE_FLAGS="${OPT_FEATURE_FLAGS} -DSQLITE_ENABLE_RTREE"
fi

#########
# See whether we should enable the SESSION extension
# Check whether --enable-session was given.
if test "${enable_session+set}" = set; then :
  enableval=$enable_session; enable_session=yes
else
  enable_session=no
fi

if test "${enable_session}" = "yes" ; then
  OPT_FEATURE_FLAGS="${OPT_FEATURE_FLAGS} -DSQLITE_ENABLE_SESSION"
  OPT_FEATURE_FLAGS="${OPT_FEATURE_FLAGS} -DSQLITE_ENABLE_PREUPDATE_HOOK"
fi

#########
# attempt to duplicate any OMITS and ENABLES into the ${OPT_FEATURE_FLAGS} parameter
for option in $CFLAGS $CPPFLAGS
do
  case $option in
    -DSQLITE_OMIT*) OPT_FEATURE_FLAGS="$OPT_FEATURE_FLAGS $option";;
    -DSQLITE_ENABLE*) OPT_FEATURE_FLAGS="$OPT_FEATURE_FLAGS $option";;
  esac
done

test $as_write_fail = 0 && chmod +x $CONFIG_STATUS || ac_write_fail=1

cat >>$CONFIG_STATUS <<\_ACEOF || ac_write_fail=1
# Save the log message, to keep $0 and so on meaningful, and to
# report actual input values of CONFIG_FILES etc. instead of their
# values after options handling.
ac_log="
This file was extended by sqlite $as_me 3.23.0, which was
generated by GNU Autoconf 2.69.  Invocation command line was

  CONFIG_FILES    = $CONFIG_FILES
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Copyright (C) 2012 Free Software Foundation, Inc.
This config.status script is free software; the Free Software Foundation
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<html>
<head>
<title>The Lemon Parser Generator</title>
</head>
<body bgcolor='white'>
<h1 align='center'>The Lemon Parser Generator</h1>

<p>Lemon is an LALR(1) parser generator for C.
It does the same job as "bison" and "yacc".
But Lemon is not a bison or yacc clone.  Lemon
uses a different grammar syntax which is designed to
reduce the number of coding errors.  Lemon also uses a
parsing engine that is faster than yacc and
bison and which is both reentrant and threadsafe.
(Update: Since the previous sentence was written, bison
has also been updated so that it too can generate a
reentrant and threadsafe parser.)
Lemon also implements features that can be used
to eliminate resource leaks, making it suitable for use
in long-running programs such as graphical user interfaces
or embedded controllers.</p>

<p>This document is an introduction to the Lemon
parser generator.</p>

<h2>Security Note</h2>

<p>The language parser code created by Lemon is very robust and
is well-suited for use in internet-facing applications that need to
safely process maliciously crafted inputs.

<p>The "lemon.exe" command-line tool itself works great when given a valid
input grammar file and almost always gives helpful
error messages for malformed inputs.  However,  it is possible for
a malicious user to craft a grammar file that will cause 
lemon.exe to crash.
We do not see this as a problem, as lemon.exe is not intended to be used
with hostile inputs.
To summarize:</p>

<ul>
<li>Parser code generated by lemon &rarr; Robust and secure
<li>The "lemon.exe" command line tool itself &rarr; Not so much
</ul>

<h2>Theory of Operation</h2>

<p>The main goal of Lemon is to translate a context free grammar (CFG)
for a particular language into C code that implements a parser for
that language.
The program has two inputs:
<ul>
<li>The grammar specification.
<li>A parser template file.
</ul>
Typically, only the grammar specification is supplied by the programmer.
Lemon comes with a default parser template which works fine for most
applications.  But the user is free to substitute a different parser
template if desired.</p>

<p>Depending on command-line options, Lemon will generate up to
three output files.
<ul>
<li>C code to implement the parser.
<li>A header file defining an integer ID for each terminal symbol.
<li>An information file that describes the states of the generated parser
    automaton.
</ul>
By default, all three of these output files are generated.

<h3>Command Line Options</h3>

<p>The behavior of Lemon can be modified using command-line options.
You can obtain a list of the available command-line options together
with a brief explanation of what each does by typing
<pre>
   lemon "-?"
</pre>
As of this writing, the following command-line options are supported:
<ul>
<li><b>-b</b>
Show only the basis for each parser state in the report file.
<li><b>-c</b>
Do not compress the generated action tables.  The parser will be a
little larger and slower, but it will detect syntax errors sooner.
<li><b>-D<i>name</i></b>
Define C preprocessor macro <i>name</i>.  This macro is usable by
"<tt><a href='#pifdef'>%ifdef</a></tt>" and
"<tt><a href='#pifdef'>%ifndef</a></tt>" lines
in the grammar file.
<li><b>-g</b>
Do not generate a parser.  Instead write the input grammar to standard
output with all comments, actions, and other extraneous text removed.
<li><b>-l</b>
Omit "#line" directives in the generated parser C code.
<li><b>-m</b>
Cause the output C source code to be compatible with the "makeheaders"
program.
<li><b>-p</b>
Display all conflicts that are resolved by
<a href='#precrules'>precedence rules</a>.
<li><b>-q</b>
Suppress generation of the report file.
<li><b>-r</b>
Do not sort or renumber the parser states as part of optimization.
<li><b>-s</b>
Show parser statistics before existing.

be parsed.  This is accomplished by calling the following function
once for each token:
<pre>
   Parse(pParser, hTokenID, sTokenData, pArg);
</pre>
The first argument to the Parse() routine is the pointer returned by
ParseAlloc().
The second argument is a small positive integer that tells the parser the
type of the next token in the data stream.
There is one token type for each terminal symbol in the grammar.
The gram.h file generated by Lemon contains #define statements that
map symbolic terminal symbol names into appropriate integer values.
A value of 0 for the second argument is a special flag to the
parser to indicate that the end of input has been reached.
The third argument is the value of the given token.  By default,
the type of the third argument is "void*", but the grammar will
usually redefine this type to be some kind of structure.
Typically the second argument will be a broad category of tokens
such as "identifier" or "number" and the third argument will
be the name of the identifier or the value of the number.</p>

<p>The Parse() function may have either three or four arguments,
depending on the grammar.  If the grammar specification file requests
it (via the <tt><a href='#extraarg'>%extra_argument</a></tt> directive),
the Parse() function will have a fourth parameter that can be
of any type chosen by the programmer.  The parser doesn't do anything
with this argument except to pass it through to action routines.
This is a convenient mechanism for passing state information down
to the action routines without having to use global variables.</p>

<p>A typical use of a Lemon parser might look something like the
following:
<pre>
    1 ParseTree *ParseFile(const char *zFilename){
    2    Tokenizer *pTokenizer;
    3    void *pParser;
    4    Token sToken;
    5    int hTokenId;
    6    ParserState sState;

    7
    8    pTokenizer = TokenizerCreate(zFilename);
    9    pParser = ParseAlloc( malloc );
   10    InitParserState(&amp;sState);
   11    while( GetNextToken(pTokenizer, &amp;hTokenId, &amp;sToken) ){
   12       Parse(pParser, hTokenId, sToken, &amp;sState);
   13    }
   14    Parse(pParser, 0, sToken, &amp;sState);
   15    ParseFree(pParser, free );
   16    TokenizerFree(pTokenizer);
   17    return sState.treeRoot;
   18 }
</pre>
This example shows a user-written routine that parses a file of
text and returns a pointer to the parse tree.
(All error-handling code is omitted from this example to keep it
simple.)
We assume the existence of some kind of tokenizer which is created
using TokenizerCreate() on line 8 and deleted by TokenizerFree()
on line 16.  The GetNextToken() function on line 11 retrieves the
next token from the input file and puts its type in the
integer variable hTokenId.  The sToken variable is assumed to be
some kind of structure that contains details about each token,
such as its complete text, what line it occurs on, etc.</p>

<p>This example also assumes the existence of structure of type
ParserState that holds state information about a particular parse.
An instance of such a structure is created on line 6 and initialized
on line 10.  A pointer to this structure is passed into the Parse()
routine as the optional 4th argument.
The action routine specified by the grammar for the parser can use
the ParserState structure to hold whatever information is useful and
appropriate.  In the example, we note that the treeRoot field of
the ParserState structure is left pointing to the root of the parse
tree.</p>

<p>The core of this example as it relates to Lemon is as follows:
<pre>
   ParseFile(){
      pParser = ParseAlloc( malloc );
      while( GetNextToken(pTokenizer,&amp;hTokenId, &amp;sToken) ){
         Parse(pParser, hTokenId, sToken);
      }
      Parse(pParser, 0, sToken);
      ParseFree(pParser, free );
   }
</pre>
Basically, what a program has to do to use a Lemon-generated parser

<p>The main purpose of the grammar specification file for Lemon is
to define the grammar for the parser.  But the input file also
specifies additional information Lemon requires to do its job.
Most of the work in using Lemon is in writing an appropriate
grammar file.</p>

<p>The grammar file for Lemon is, for the most part, free format.
It does not have sections or divisions like yacc or bison.  Any
declaration can occur at any point in the file.
Lemon ignores whitespace (except where it is needed to separate
tokens), and it honors the same commenting conventions as C and C++.</p>

<h3>Terminals and Nonterminals</h3>

<p>A terminal symbol (token) is any string of alphanumeric
and/or underscore characters
that begins with an uppercase letter.
A terminal can contain lowercase letters after the first character,
but the usual convention is to make terminals all uppercase.
A nonterminal, on the other hand, is any string of alphanumeric
and underscore characters than begins with a lowercase letter.
Again, the usual convention is to make nonterminals use all lowercase
letters.</p>

<p>In Lemon, terminal and nonterminal symbols do not need to
be declared or identified in a separate section of the grammar file.
Lemon is able to generate a list of all terminals and nonterminals
by examining the grammar rules, and it can always distinguish a
terminal from a nonterminal by checking the case of the first
character of the name.</p>

<p>Yacc and bison allow terminal symbols to have either alphanumeric

Each grammar rule consists of a nonterminal symbol followed by
the special symbol "::=" and then a list of terminals and/or nonterminals.
The rule is terminated by a period.
The list of terminals and nonterminals on the right-hand side of the
rule can be empty.
Rules can occur in any order, except that the left-hand side of the
first rule is assumed to be the start symbol for the grammar (unless
specified otherwise using the <tt><a href='#start_symbol'>%start_symbol</a></tt>
directive described below.)
A typical sequence of grammar rules might look something like this:
<pre>
  expr ::= expr PLUS expr.
  expr ::= expr TIMES expr.
  expr ::= LPAREN expr RPAREN.
  expr ::= VALUE.
</pre>

rule and say "$7" when you really mean "$8".</p>

<p>Lemon avoids the need to count grammar symbols by assigning symbolic
names to each symbol in a grammar rule and then using those symbolic
names in the action.
In yacc or bison, one would write this:
<pre>
  expr -&gt; expr PLUS expr  { $$ = $1 + $3; };
</pre>
But in Lemon, the same rule becomes the following:
<pre>
  expr(A) ::= expr(B) PLUS expr(C).  { A = B+C; }
</pre>
In the Lemon rule, any symbol in parentheses after a grammar rule
symbol becomes a place holder for that symbol in the grammar rule.

<p>Lemon resolves parsing ambiguities in exactly the same way as
yacc and bison.  A shift-reduce conflict is resolved in favor
of the shift, and a reduce-reduce conflict is resolved by reducing
whichever rule comes first in the grammar file.</p>

<p>Just like in
yacc and bison, Lemon allows a measure of control
over the resolution of parsing conflicts using precedence rules.
A precedence value can be assigned to any terminal symbol
using the
<tt><a href='#pleft'>%left</a></tt>,
<tt><a href='#pright'>%right</a></tt> or
<tt><a href='#pnonassoc'>%nonassoc</a></tt> directives.  Terminal symbols
mentioned in earlier directives have a lower precedence than
terminal symbols mentioned in later directives.  For example:</p>

<p><pre>
   %left AND.
   %left OR.
   %nonassoc EQ NE GT GE LT LE.
   %left PLUS MINUS.

<ul>
<li> If either the token to be shifted or the rule to be reduced
     lacks precedence information, then resolve in favor of the
     shift, but report a parsing conflict.
<li> If the precedence of the token to be shifted is greater than
     the precedence of the rule to reduce, then resolve in favor
     of the shift.  No parsing conflict is reported.
<li> If the precedence of the token to be shifted is less than the
     precedence of the rule to reduce, then resolve in favor of the
     reduce action.  No parsing conflict is reported.
<li> If the precedences are the same and the shift token is
     right-associative, then resolve in favor of the shift.
     No parsing conflict is reported.
<li> If the precedences are the same and the shift token is
     left-associative, then resolve in favor of the reduce.
     No parsing conflict is reported.
<li> Otherwise, resolve the conflict by doing the shift, and
     report a parsing conflict.
</ul>
Reduce-reduce conflicts are resolved this way:
<ul>
<li> If either reduce rule
     lacks precedence information, then resolve in favor of the
     rule that appears first in the grammar, and report a parsing
     conflict.
<li> If both rules have precedence and the precedence is different,
     then resolve the dispute in favor of the rule with the highest
     precedence, and do not report a conflict.
<li> Otherwise, resolve the conflict by reducing by the rule that
     appears first in the grammar, and report a parsing conflict.
</ul>

<h3>Special Directives</h3>

<p>The input grammar to Lemon consists of grammar rules and special
directives.  We've described all the grammar rules, so now we'll
talk about the special directives.</p>

<p>Directives in Lemon can occur in any order.  You can put them before
the grammar rules, or after the grammar rules, or in the midst of the
grammar rules.  It doesn't matter.  The relative order of
directives used to assign precedence to terminals is important, but
other than that, the order of directives in Lemon is arbitrary.</p>

<p>Lemon supports the following special directives:
<ul>
<li><tt><a href='#pcode'>%code</a></tt>
<li><tt><a href='#default_destructor'>%default_destructor</a></tt>
<li><tt><a href='#default_type'>%default_type</a></tt>
<li><tt><a href='#destructor'>%destructor</a></tt>
<li><tt><a href='#pifdef'>%endif</a></tt>
<li><tt><a href='#extraarg'>%extra_argument</a></tt>
<li><tt><a href='#pfallback'>%fallback</a></tt>
<li><tt><a href='#pifdef'>%ifdef</a></tt>
<li><tt><a href='#pifdef'>%ifndef</a></tt>
<li><tt><a href='#pinclude'>%include</a></tt>
<li><tt><a href='#pleft'>%left</a></tt>
<li><tt><a href='#pname'>%name</a></tt>
<li><tt><a href='#pnonassoc'>%nonassoc</a></tt>
<li><tt><a href='#parse_accept'>%parse_accept</a></tt>
<li><tt><a href='#parse_failure'>%parse_failure</a></tt>
<li><tt><a href='#pright'>%right</a></tt>
<li><tt><a href='#stack_overflow'>%stack_overflow</a></tt>
<li><tt><a href='#stack_size'>%stack_size</a></tt>
<li><tt><a href='#start_symbol'>%start_symbol</a></tt>
<li><tt><a href='#syntax_error'>%syntax_error</a></tt>
<li><tt><a href='#token_class'>%token_class</a></tt>
<li><tt><a href='#token_destructor'>%token_destructor</a></tt>
<li><tt><a href='#token_prefix'>%token_prefix</a></tt>
<li><tt><a href='#token_type'>%token_type</a></tt>
<li><tt><a href='#ptype'>%type</a></tt>
<li><tt><a href='#pwildcard'>%wildcard</a></tt>
</ul>
Each of these directives will be described separately in the
following sections:</p>

<a name='pcode'></a>
<h4>The <tt>%code</tt> directive</h4>

<p>The <tt>%code</tt> directive is used to specify additional C code that
is added to the end of the main output file.  This is similar to
the <tt><a href='#pinclude'>%include</a></tt> directive except that
<tt>%include</tt> is inserted at the beginning of the main output file.</p>

<p><tt>%code</tt> is typically used to include some action routines or perhaps
a tokenizer or even the "main()" function
as part of the output file.</p>

<a name='default_destructor'></a>
<h4>The <tt>%default_destructor</tt> directive</h4>

<p>The <tt>%default_destructor</tt> directive specifies a destructor to
use for non-terminals that do not have their own destructor
specified by a separate <tt>%destructor</tt> directive.  See the documentation
on the <tt><a name='#destructor'>%destructor</a></tt> directive below for
additional information.</p>

<p>In some grammars, many different non-terminal symbols have the
same data type and hence the same destructor.  This directive is
a convenient way to specify the same destructor for all those
non-terminals using a single statement.</p>

<a name='default_type'></a>
<h4>The <tt>%default_type</tt> directive</h4>

<p>The <tt>%default_type</tt> directive specifies the data type of non-terminal
symbols that do not have their own data type defined using a separate
<tt><a href='#ptype'>%type</a></tt> directive.</p>


<a name='destructor'></a>
<h4>The <tt>%destructor</tt> directive</h4>

<p>The <tt>%destructor</tt> directive is used to specify a destructor for
a non-terminal symbol.
(See also the <tt><a href='#token_destructor'>%token_destructor</a></tt>
directive which is used to specify a destructor for terminal symbols.)</p>

<p>A non-terminal's destructor is called to dispose of the
non-terminal's value whenever the non-terminal is popped from
the stack.  This includes all of the following circumstances:
<ul>
<li> When a rule reduces and the value of a non-terminal on

<p>Consider an example:
<pre>
   %type nt {void*}
   %destructor nt { free($$); }
   nt(A) ::= ID NUM.   { A = malloc( 100 ); }
</pre>
This example is a bit contrived, but it serves to illustrate how
destructors work.  The example shows a non-terminal named
"nt" that holds values of type "void*".  When the rule for
an "nt" reduces, it sets the value of the non-terminal to
space obtained from malloc().  Later, when the nt non-terminal
is popped from the stack, the destructor will fire and call
free() on this malloced space, thus avoiding a memory leak.
(Note that the symbol "$$" in the destructor code is replaced
by the value of the non-terminal.)</p>

<p>It is important to note that the value of a non-terminal is passed
to the destructor whenever the non-terminal is removed from the
stack, unless the non-terminal is used in a C-code action.  If
the non-terminal is used by C-code, then it is assumed that the
C-code will take care of destroying it.
More commonly, the value is used to build some
larger structure, and we don't want to destroy it, which is why
the destructor is not called in this circumstance.</p>

<p>Destructors help avoid memory leaks by automatically freeing
allocated objects when they go out of scope.
To do the same using yacc or bison is much more difficult.</p>

<a name='extraarg'></a>
<h4>The <tt>%extra_argument</tt> directive</h4>

The <tt>%extra_argument</tt> directive instructs Lemon to add a 4th parameter
to the parameter list of the Parse() function it generates.  Lemon
doesn't do anything itself with this extra argument, but it does
make the argument available to C-code action routines, destructors,
and so forth.  For example, if the grammar file contains:</p>

<p><pre>
    %extra_argument { MyStruct *pAbc }
</pre></p>

<p>Then the Parse() function generated will have an 4th parameter
of type "MyStruct*" and all action routines will have access to
a variable named "pAbc" that is the value of the 4th parameter
in the most recent call to Parse().</p>

<a name='pfallback'></a>
<h4>The <tt>%fallback</tt> directive</h4>

<p>The <tt>%fallback</tt> directive specifies an alternative meaning for one
or more tokens.  The alternative meaning is tried if the original token
would have generated a syntax error.</p>

<p>The <tt>%fallback</tt> directive was added to support robust parsing of SQL
syntax in <a href='https://www.sqlite.org/'>SQLite</a>.
The SQL language contains a large assortment of keywords, each of which
appears as a different token to the language parser.  SQL contains so
many keywords that it can be difficult for programmers to keep up with
them all.  Programmers will, therefore, sometimes mistakenly use an
obscure language keyword for an identifier.  The <tt>%fallback</tt> directive
provides a mechanism to tell the parser:  "If you are unable to parse
this keyword, try treating it as an identifier instead."</p>

<p>The syntax of <tt>%fallback</tt> is as follows:

<blockquote>
<tt>%fallback</tt> <i>ID</i> <i>TOKEN...</i> <b>.</b>
</blockquote></p>

<p>In words, the <tt>%fallback</tt> directive is followed by a list of token
names terminated by a period.
The first token name is the fallback token &mdash; the
token to which all the other tokens fall back to.  The second and subsequent
arguments are tokens which fall back to the token identified by the first
argument.</p>

<a name='pifdef'></a>
<h4>The <tt>%ifdef</tt>, <tt>%ifndef</tt>, and <tt>%endif</tt> directives</h4>

<p>The <tt>%ifdef</tt>, <tt>%ifndef</tt>, and <tt>%endif</tt> directives
are similar to #ifdef, #ifndef, and #endif in the C-preprocessor,
just not as general.
Each of these directives must begin at the left margin.  No whitespace
is allowed between the "%" and the directive name.</p>

<p>Grammar text in between "<tt>%ifdef MACRO</tt>" and the next nested
"<tt>%endif</tt>" is
ignored unless the "-DMACRO" command-line option is used.  Grammar text
betwen "<tt>%ifndef MACRO</tt>" and the next nested "<tt>%endif</tt>" is
included except when the "-DMACRO" command-line option is used.</p>

<p>Note that the argument to <tt>%ifdef</tt> and <tt>%ifndef</tt> must
be a single preprocessor symbol name, not a general expression.
There is no "<tt>%else</tt>" directive.</p>


<a name='pinclude'></a>
<h4>The <tt>%include</tt> directive</h4>

<p>The <tt>%include</tt> directive specifies C code that is included at the
top of the generated parser.  You can include any text you want &mdash;
the Lemon parser generator copies it blindly.  If you have multiple
<tt>%include</tt> directives in your grammar file, their values are concatenated
so that all <tt>%include</tt> code ultimately appears near the top of the
generated parser, in the same order as it appeared in the grammar.</p>

<p>The <tt>%include</tt> directive is very handy for getting some extra #include
preprocessor statements at the beginning of the generated parser.
For example:</p>

<p><pre>
   %include {#include &lt;unistd.h&gt;}
</pre></p>

<p>This might be needed, for example, if some of the C actions in the
grammar call functions that are prototyped in unistd.h.</p>

<a name='pleft'></a>
<h4>The <tt>%left</tt> directive</h4>

The <tt>%left</tt> directive is used (along with the
<tt><a href='#pright'>%right</a></tt> and
<tt><a href='#pnonassoc'>%nonassoc</a></tt> directives) to declare
precedences of terminal symbols.
Every terminal symbol whose name appears after
a <tt>%left</tt> directive but before the next period (".") is
given the same left-associative precedence value.  Subsequent
<tt>%left</tt> directives have higher precedence.  For example:</p>

<p><pre>
   %left AND.
   %left OR.
   %nonassoc EQ NE GT GE LT LE.
   %left PLUS MINUS.
   %left TIMES DIVIDE MOD.
   %right EXP NOT.
</pre></p>

<p>Note the period that terminates each <tt>%left</tt>,
<tt>%right</tt> or <tt>%nonassoc</tt>
directive.</p>

<p>LALR(1) grammars can get into a situation where they require
a large amount of stack space if you make heavy use or right-associative
operators.  For this reason, it is recommended that you use <tt>%left</tt>
rather than <tt>%right</tt> whenever possible.</p>

<a name='pname'></a>
<h4>The <tt>%name</tt> directive</h4>

<p>By default, the functions generated by Lemon all begin with the
five-character string "Parse".  You can change this string to something
different using the <tt>%name</tt> directive.  For instance:</p>

<p><pre>
   %name Abcde
</pre></p>

<p>Putting this directive in the grammar file will cause Lemon to generate
functions named
<ul>
<li> AbcdeAlloc(),
<li> AbcdeFree(),
<li> AbcdeTrace(), and
<li> Abcde().
</ul>
The <tt>%name</tt> directive allows you to generate two or more different
parsers and link them all into the same executable.</p>


<a name='pnonassoc'></a>
<h4>The <tt>%nonassoc</tt> directive</h4>

<p>This directive is used to assign non-associative precedence to
one or more terminal symbols.  See the section on
<a href='#precrules'>precedence rules</a>
or on the <tt><a href='#pleft'>%left</a></tt> directive
for additional information.</p>

<a name='parse_accept'></a>
<h4>The <tt>%parse_accept</tt> directive</h4>

<p>The <tt>%parse_accept</tt> directive specifies a block of C code that is
executed whenever the parser accepts its input string.  To "accept"
an input string means that the parser was able to process all tokens
without error.</p>

<p>For example:</p>

<p><pre>
   %parse_accept {
      printf("parsing complete!\n");
   }
</pre></p>

<a name='parse_failure'></a>
<h4>The <tt>%parse_failure</tt> directive</h4>

<p>The <tt>%parse_failure</tt> directive specifies a block of C code that
is executed whenever the parser fails complete.  This code is not
executed until the parser has tried and failed to resolve an input
error using is usual error recovery strategy.  The routine is
only invoked when parsing is unable to continue.</p>

<p><pre>
   %parse_failure {
     fprintf(stderr,"Giving up.  Parser is hopelessly lost...\n");
   }
</pre></p>

<a name='pright'></a>
<h4>The <tt>%right</tt> directive</h4>

<p>This directive is used to assign right-associative precedence to
one or more terminal symbols.  See the section on
<a href='#precrules'>precedence rules</a>
or on the <a href='#pleft'>%left</a> directive for additional information.</p>

<a name='stack_overflow'></a>
<h4>The <tt>%stack_overflow</tt> directive</h4>

<p>The <tt>%stack_overflow</tt> directive specifies a block of C code that
is executed if the parser's internal stack ever overflows.  Typically
this just prints an error message.  After a stack overflow, the parser
will be unable to continue and must be reset.</p>

<p><pre>
   %stack_overflow {
     fprintf(stderr,"Giving up.  Parser stack overflow\n");
   }
</pre></p>

<p>You can help prevent parser stack overflows by avoiding the use
of right recursion and right-precedence operators in your grammar.
Use left recursion and and left-precedence operators instead to
encourage rules to reduce sooner and keep the stack size down.
For example, do rules like this:
<pre>
   list ::= list element.      // left-recursion.  Good!
   list ::= .
</pre>
Not like this:
<pre>
   list ::= element list.      // right-recursion.  Bad!
   list ::= .
</pre></p>

<a name='stack_size'></a>
<h4>The <tt>%stack_size</tt> directive</h4>

<p>If stack overflow is a problem and you can't resolve the trouble
by using left-recursion, then you might want to increase the size
of the parser's stack using this directive.  Put an positive integer
after the <tt>%stack_size</tt> directive and Lemon will generate a parse
with a stack of the requested size.  The default value is 100.</p>

<p><pre>
   %stack_size 2000
</pre></p>

<a name='start_symbol'></a>
<h4>The <tt>%start_symbol</tt> directive</h4>

<p>By default, the start symbol for the grammar that Lemon generates
is the first non-terminal that appears in the grammar file.  But you
can choose a different start symbol using the
<tt>%start_symbol</tt> directive.</p>

<p><pre>
   %start_symbol  prog
</pre></p>

<a name='syntax_error'></a>
<h4>The <tt>%syntax_error</tt> directive</h4>

<p>See <a href='#error_processing'>Error Processing</a>.</p>

<a name='token_class'></a>
<h4>The <tt>%token_class</tt> directive</h4>

<p>Undocumented.  Appears to be related to the MULTITERMINAL concept.
<a href='http://sqlite.org/src/fdiff?v1=796930d5fc2036c7&v2=624b24c5dc048e09&sbs=0'>Implementation</a>.</p>

<a name='token_destructor'></a>
<h4>The <tt>%token_destructor</tt> directive</h4>

<p>The <tt>%destructor</tt> directive assigns a destructor to a non-terminal
symbol.  (See the description of the
<tt><a href='%destructor'>%destructor</a></tt> directive above.)
The <tt>%token_destructor</tt> directive does the same thing
for all terminal symbols.</p>

<p>Unlike non-terminal symbols which may each have a different data type
for their values, terminals all use the same data type (defined by
the <tt><a href='#token_type'>%token_type</a></tt> directive)
and so they use a common destructor.
Other than that, the token destructor works just like the non-terminal
destructors.</p>

<a name='token_prefix'></a>
<h4>The <tt>%token_prefix</tt> directive</h4>

<p>Lemon generates #defines that assign small integer constants
to each terminal symbol in the grammar.  If desired, Lemon will
add a prefix specified by this directive
to each of the #defines it generates.</p>

<p>So if the default output of Lemon looked like this:
<pre>
    #define AND              1
    #define MINUS            2
    #define OR               3
    #define PLUS             4
</pre>
You can insert a statement into the grammar like this:
<pre>
    %token_prefix    TOKEN_
</pre>
to cause Lemon to produce these symbols instead:
<pre>
    #define TOKEN_AND        1
    #define TOKEN_MINUS      2
    #define TOKEN_OR         3
    #define TOKEN_PLUS       4
</pre></p>

<a name='token_type'></a><a name='ptype'></a>
<h4>The <tt>%token_type</tt> and <tt>%type</tt> directives</h4>

<p>These directives are used to specify the data types for values
on the parser's stack associated with terminal and non-terminal
symbols.  The values of all terminal symbols must be of the same
type.  This turns out to be the same data type as the 3rd parameter
to the Parse() function generated by Lemon.  Typically, you will
make the value of a terminal symbol by a pointer to some kind of
token structure.  Like this:</p>

<p><pre>
   %token_type    {Token*}
</pre></p>

<p>If the data type of terminals is not specified, the default value
is "void*".</p>

<p>Non-terminal symbols can each have their own data types.  Typically
the data type of a non-terminal is a pointer to the root of a parse tree
structure that contains all information about that non-terminal.
For example:</p>

<p><pre>
   %type   expr  {Expr*}
</pre></p>

<p>Each entry on the parser's stack is actually a union containing
instances of all data types for every non-terminal and terminal symbol.
Lemon will automatically use the correct element of this union depending
on what the corresponding non-terminal or terminal symbol is.  But
the grammar designer should keep in mind that the size of the union
will be the size of its largest element.  So if you have a single
non-terminal whose data type requires 1K of storage, then your 100
entry parser stack will require 100K of heap space.  If you are willing
and able to pay that price, fine.  You just need to know.</p>

<a name='pwildcard'></a>
<h4>The <tt>%wildcard</tt> directive</h4>

<p>The <tt>%wildcard</tt> directive is followed by a single token name and a
period.  This directive specifies that the identified token should
match any input token.</p>

<p>When the generated parser has the choice of matching an input against
the wildcard token and some other token, the other token is always used.
The wildcard token is only matched if there are no alternatives.</p>

<a name='error_processing'></a>
<h3>Error Processing</h3>

<p>After extensive experimentation over several years, it has been
discovered that the error recovery strategy used by yacc is about
as good as it gets.  And so that is what Lemon uses.</p>

<p>When a Lemon-generated parser encounters a syntax error, it
first invokes the code specified by the <tt>%syntax_error</tt> directive, if
any.  It then enters its error recovery strategy.  The error recovery
strategy is to begin popping the parsers stack until it enters a
state where it is permitted to shift a special non-terminal symbol
named "error".  It then shifts this non-terminal and continues
parsing.  The <tt>%syntax_error</tt> routine will not be called again
until at least three new tokens have been successfully shifted.</p>

<p>If the parser pops its stack until the stack is empty, and it still
is unable to shift the error symbol, then the
<tt><a href='#parse_failure'>%parse_failure</a></tt> routine
is invoked and the parser resets itself to its start state, ready
to begin parsing a new file.  This is what will happen at the very
first syntax error, of course, if there are no instances of the
"error" non-terminal in your grammar.</p>

</body>
</html>

## SQLite Expert Extension

This folder contains code for a simple system to propose useful indexes
given a database and a set of SQL queries. It works as follows:

  1. The user database schema is copied to a temporary database.

  1. All SQL queries are prepared against the temporary database.
     Information regarding the WHERE and ORDER BY clauses, and other query
     features that affect index selection are recorded.

  1. The information gathered in step 2 is used to create candidate 
     indexes - indexes that the planner might have made use of in the previous
     step, had they been available.

  1. A subset of the data in the user database is used to generate statistics
     for all existing indexes and the candidate indexes generated in step 3
     above.

  1. The SQL queries are prepared a second time. If the planner uses any
     of the indexes created in step 3, they are recommended to the user.

# C API

The SQLite expert C API is defined in sqlite3expert.h. Most uses will proceed
as follows:

  1. An sqlite3expert object is created by calling **sqlite3\_expert\_new()**.
     A database handle opened by the user is passed as an argument.

  1. The sqlite3expert object is configured with one or more SQL statements
     by making one or more calls to **sqlite3\_expert\_sql()**. Each call may
     specify a single SQL statement, or multiple statements separated by
     semi-colons.
  
  1. Optionally, the **sqlite3\_expert\_config()** API may be used to 
     configure the size of the data subset used to generate index statistics.
     Using a smaller subset of the data can speed up the analysis.

  1. **sqlite3\_expert\_analyze()** is called to run the analysis.

  1. One or more calls are made to **sqlite3\_expert\_report()** to extract
     components of the results of the analysis.

  1. **sqlite3\_expert\_destroy()** is called to free all resources.

Refer to comments in sqlite3expert.h for further details.

# sqlite3_expert application

The file "expert.c" contains the code for a command line application that
uses the API described above. It can be compiled with (for example):

<pre>
  gcc -O2 sqlite3.c expert.c sqlite3expert.c -o sqlite3_expert
</pre>

Assuming the database is named "test.db", it can then be run to analyze a
single query:

<pre>
  ./sqlite3_expert -sql &lt;sql-query&gt; test.db
</pre>

Or an entire text file worth of queries with:

<pre>
  ./sqlite3_expert -file &lt;text-file&gt; test.db
</pre>

By default, sqlite3\_expert generates index statistics using all the data in
the user database. For a large database, this may be prohibitively time
consuming. The "-sample" option may be used to configure sqlite3\_expert to
generate statistics based on an integer percentage of the user database as
follows:

<pre>
  # Generate statistics based on 25% of the user database rows:
  ./sqlite3_expert -sample 25 -sql &lt;sql-query&gt; test.db

  # Do not generate any statistics at all:
  ./sqlite3_expert -sample 0 -sql &lt;sql-query&gt; test.db
</pre>

/*
** 2017 April 07
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
*/


#include <sqlite3.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "sqlite3expert.h"


static void option_requires_argument(const char *zOpt){
  fprintf(stderr, "Option requires an argument: %s\n", zOpt);
  exit(-3);
}

static int option_integer_arg(const char *zVal){
  return atoi(zVal);
}

static void usage(char **argv){
  fprintf(stderr, "\n");
  fprintf(stderr, "Usage %s ?OPTIONS? DATABASE\n", argv[0]);
  fprintf(stderr, "\n");
  fprintf(stderr, "Options are:\n");
  fprintf(stderr, "  -sql SQL   (analyze SQL statements passed as argument)\n");
  fprintf(stderr, "  -file FILE (read SQL statements from file FILE)\n");
  fprintf(stderr, "  -verbose LEVEL (integer verbosity level. default 1)\n");
  fprintf(stderr, "  -sample PERCENT (percent of db to sample. default 100)\n");
  exit(-1);
}

static int readSqlFromFile(sqlite3expert *p, const char *zFile, char **pzErr){
  FILE *in = fopen(zFile, "rb");
  long nIn;
  size_t nRead;
  char *pBuf;
  int rc;
  if( in==0 ){
    *pzErr = sqlite3_mprintf("failed to open file %s\n", zFile);
    return SQLITE_ERROR;
  }
  fseek(in, 0, SEEK_END);
  nIn = ftell(in);
  rewind(in);
  pBuf = sqlite3_malloc64( nIn+1 );
  nRead = fread(pBuf, nIn, 1, in);
  fclose(in);
  if( nRead!=1 ){
    sqlite3_free(pBuf);
    *pzErr = sqlite3_mprintf("failed to read file %s\n", zFile);
    return SQLITE_ERROR;
  }
  pBuf[nIn] = 0;
  rc = sqlite3_expert_sql(p, pBuf, pzErr);
  sqlite3_free(pBuf);
  return rc;
}

int main(int argc, char **argv){
  const char *zDb;
  int rc = 0;
  char *zErr = 0;
  int i;
  int iVerbose = 1;               /* -verbose option */

  sqlite3 *db = 0;
  sqlite3expert *p = 0;

  if( argc<2 ) usage(argv);
  zDb = argv[argc-1];
  if( zDb[0]=='-' ) usage(argv);
  rc = sqlite3_open(zDb, &db);
  if( rc!=SQLITE_OK ){
    fprintf(stderr, "Cannot open db file: %s - %s\n", zDb, sqlite3_errmsg(db));
    exit(-2);
  }

  p = sqlite3_expert_new(db, &zErr);
  if( p==0 ){
    fprintf(stderr, "Cannot run analysis: %s\n", zErr);
    rc = 1;
  }else{
    for(i=1; i<(argc-1); i++){
      char *zArg = argv[i];
      int nArg;
      if( zArg[0]=='-' && zArg[1]=='-' && zArg[2]!=0 ) zArg++;
      nArg = (int)strlen(zArg);
      if( nArg>=2 && 0==sqlite3_strnicmp(zArg, "-file", nArg) ){
        if( ++i==(argc-1) ) option_requires_argument("-file");
        rc = readSqlFromFile(p, argv[i], &zErr);
      }

      else if( nArg>=3 && 0==sqlite3_strnicmp(zArg, "-sql", nArg) ){
        if( ++i==(argc-1) ) option_requires_argument("-sql");
        rc = sqlite3_expert_sql(p, argv[i], &zErr);
      }

      else if( nArg>=3 && 0==sqlite3_strnicmp(zArg, "-sample", nArg) ){
        int iSample;
        if( ++i==(argc-1) ) option_requires_argument("-sample");
        iSample = option_integer_arg(argv[i]);
        sqlite3_expert_config(p, EXPERT_CONFIG_SAMPLE, iSample);
      }

      else if( nArg>=2 && 0==sqlite3_strnicmp(zArg, "-verbose", nArg) ){
        if( ++i==(argc-1) ) option_requires_argument("-verbose");
        iVerbose = option_integer_arg(argv[i]);
      }

      else{
        usage(argv);
      }
    }
  }

  if( rc==SQLITE_OK ){
    rc = sqlite3_expert_analyze(p, &zErr);
  }

  if( rc==SQLITE_OK ){
    int nQuery = sqlite3_expert_count(p);
    if( iVerbose>0 ){
      const char *zCand = sqlite3_expert_report(p,0,EXPERT_REPORT_CANDIDATES);
      fprintf(stdout, "-- Candidates -------------------------------\n");
      fprintf(stdout, "%s\n", zCand);
    }
    for(i=0; i<nQuery; i++){
      const char *zSql = sqlite3_expert_report(p, i, EXPERT_REPORT_SQL);
      const char *zIdx = sqlite3_expert_report(p, i, EXPERT_REPORT_INDEXES);
      const char *zEQP = sqlite3_expert_report(p, i, EXPERT_REPORT_PLAN);
      if( zIdx==0 ) zIdx = "(no new indexes)\n";
      if( iVerbose>0 ){
        fprintf(stdout, "-- Query %d ----------------------------------\n",i+1);
        fprintf(stdout, "%s\n\n", zSql);
      }
      fprintf(stdout, "%s\n%s\n", zIdx, zEQP);
    }
  }else{
    fprintf(stderr, "Error: %s\n", zErr ? zErr : "?");
  }

  sqlite3_expert_destroy(p);
  sqlite3_free(zErr);
  return rc;
}

# 2009 Nov 11
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
#
# The focus of this file is testing the CLI shell tool. Specifically,
# the ".recommend" command.
#
#

# Test plan:
#
#
if {![info exists testdir]} {
  set testdir [file join [file dirname [info script]] .. .. test]
}
source $testdir/tester.tcl
set testprefix expert1

if {[info commands sqlite3_expert_new]==""} {
  finish_test
  return
}

set CLI [test_binary_name sqlite3]
set CMD [test_binary_name sqlite3_expert]

proc squish {txt} {
  regsub -all {[[:space:]]+} $txt { }
}

proc do_setup_rec_test {tn setup sql res} {
  reset_db
  db eval $setup
  uplevel [list do_rec_test $tn $sql $res]
}

foreach {tn setup} {
  1 {
    if {![file executable $CMD]} { continue }

    proc do_rec_test {tn sql res} {
      set res [squish [string trim $res]]
      set tst [subst -nocommands { 
        squish [string trim [exec $::CMD -verbose 0 -sql {$sql;} test.db]]
      }]
      uplevel [list do_test $tn $tst $res]
    }
  }
  2 {
    if {[info commands sqlite3_expert_new]==""} { continue }

    proc do_rec_test {tn sql res} {
      set expert [sqlite3_expert_new db]
      $expert sql $sql
      $expert analyze

      set result [list]
      for {set i 0} {$i < [$expert count]} {incr i} {
        set idx [string trim [$expert report $i indexes]]
        if {$idx==""} {set idx "(no new indexes)"}
        lappend result $idx
        lappend result [string trim [$expert report $i plan]]
      }

      $expert destroy

      set tst [subst -nocommands {set {} [squish [join {$result}]]}]
      uplevel [list do_test $tn $tst [string trim [squish $res]]]
    }
  }
  3 {
    if {![file executable $CLI]} { continue }

    proc do_rec_test {tn sql res} {
      set res [squish [string trim $res]]
      set tst [subst -nocommands { 
        squish [string trim [exec $::CLI test.db ".expert" {$sql;}]]
      }]
      uplevel [list do_test $tn $tst $res]
    }
  }
} {

  eval $setup


do_setup_rec_test $tn.1 { CREATE TABLE t1(a, b, c) } {
  SELECT * FROM t1
} {
  (no new indexes)
  0|0|0|SCAN TABLE t1
}

do_setup_rec_test $tn.2 {
  CREATE TABLE t1(a, b, c);
} {
  SELECT * FROM t1 WHERE b>?;
} {
  CREATE INDEX t1_idx_00000062 ON t1(b);
  0|0|0|SEARCH TABLE t1 USING INDEX t1_idx_00000062 (b>?)
}

do_setup_rec_test $tn.3 {
  CREATE TABLE t1(a, b, c);
} {
  SELECT * FROM t1 WHERE b COLLATE nocase BETWEEN ? AND ?
} {
  CREATE INDEX t1_idx_3e094c27 ON t1(b COLLATE NOCASE);
  0|0|0|SEARCH TABLE t1 USING INDEX t1_idx_3e094c27 (b>? AND b<?)
}

do_setup_rec_test $tn.4 {
  CREATE TABLE t1(a, b, c);
} {
  SELECT a FROM t1 ORDER BY b;
} {
  CREATE INDEX t1_idx_00000062 ON t1(b);
  0|0|0|SCAN TABLE t1 USING INDEX t1_idx_00000062
}

do_setup_rec_test $tn.5 {
  CREATE TABLE t1(a, b, c);
} {
  SELECT a FROM t1 WHERE a=? ORDER BY b;
} {
  CREATE INDEX t1_idx_000123a7 ON t1(a, b);
  0|0|0|SEARCH TABLE t1 USING COVERING INDEX t1_idx_000123a7 (a=?)
}

do_setup_rec_test $tn.6 {
  CREATE TABLE t1(a, b, c);
} {
  SELECT min(a) FROM t1
} {
  CREATE INDEX t1_idx_00000061 ON t1(a);
  0|0|0|SEARCH TABLE t1 USING COVERING INDEX t1_idx_00000061
}

do_setup_rec_test $tn.7 {
  CREATE TABLE t1(a, b, c);
} {
  SELECT * FROM t1 ORDER BY a, b, c;
} {
  CREATE INDEX t1_idx_033e95fe ON t1(a, b, c);
  0|0|0|SCAN TABLE t1 USING COVERING INDEX t1_idx_033e95fe
}

#do_setup_rec_test $tn.1.8 {
#  CREATE TABLE t1(a, b, c);
#} {
#  SELECT * FROM t1 ORDER BY a ASC, b COLLATE nocase DESC, c ASC;
#} {
#  CREATE INDEX t1_idx_5be6e222 ON t1(a, b COLLATE NOCASE DESC, c);
#  0|0|0|SCAN TABLE t1 USING COVERING INDEX t1_idx_5be6e222
#}

do_setup_rec_test $tn.8.1 {
  CREATE TABLE t1(a COLLATE NOCase, b, c);
} {
  SELECT * FROM t1 WHERE a=?
} {
  CREATE INDEX t1_idx_00000061 ON t1(a);
  0|0|0|SEARCH TABLE t1 USING INDEX t1_idx_00000061 (a=?)
}
do_setup_rec_test $tn.8.2 {
  CREATE TABLE t1(a, b COLLATE nocase, c);
} {
  SELECT * FROM t1 ORDER BY a ASC, b DESC, c ASC;
} {
  CREATE INDEX t1_idx_5cb97285 ON t1(a, b DESC, c);
  0|0|0|SCAN TABLE t1 USING COVERING INDEX t1_idx_5cb97285
}


# Tables with names that require quotes.
#
do_setup_rec_test $tn.9.1 {
  CREATE TABLE "t t"(a, b, c);
} {
  SELECT * FROM "t t" WHERE a=?
} {
  CREATE INDEX 't t_idx_00000061' ON 't t'(a);
  0|0|0|SEARCH TABLE t t USING INDEX t t_idx_00000061 (a=?) 
}

do_setup_rec_test $tn.9.2 {
  CREATE TABLE "t t"(a, b, c);
} {
  SELECT * FROM "t t" WHERE b BETWEEN ? AND ?
} {
  CREATE INDEX 't t_idx_00000062' ON 't t'(b);
  0|0|0|SEARCH TABLE t t USING INDEX t t_idx_00000062 (b>? AND b<?)
}

# Columns with names that require quotes.
#
do_setup_rec_test $tn.10.1 {
  CREATE TABLE t3(a, "b b", c);
} {
  SELECT * FROM t3 WHERE "b b" = ?
} {
  CREATE INDEX t3_idx_00050c52 ON t3('b b');
  0|0|0|SEARCH TABLE t3 USING INDEX t3_idx_00050c52 (b b=?)
}

do_setup_rec_test $tn.10.2 {
  CREATE TABLE t3(a, "b b", c);
} {
  SELECT * FROM t3 ORDER BY "b b"
} {
  CREATE INDEX t3_idx_00050c52 ON t3('b b');
  0|0|0|SCAN TABLE t3 USING INDEX t3_idx_00050c52
}

# Transitive constraints
#
do_setup_rec_test $tn.11.1 {
  CREATE TABLE t5(a, b);
  CREATE TABLE t6(c, d);
} {
  SELECT * FROM t5, t6 WHERE a=? AND b=c AND c=?
} {
  CREATE INDEX t5_idx_000123a7 ON t5(a, b);
  CREATE INDEX t6_idx_00000063 ON t6(c);
  0|0|1|SEARCH TABLE t6 USING INDEX t6_idx_00000063 (c=?) 
  0|1|0|SEARCH TABLE t5 USING COVERING INDEX t5_idx_000123a7 (a=? AND b=?)
}

# OR terms.
#
do_setup_rec_test $tn.12.1 {
  CREATE TABLE t7(a, b);
} {
  SELECT * FROM t7 WHERE a=? OR b=?
} {
  CREATE INDEX t7_idx_00000062 ON t7(b);
  CREATE INDEX t7_idx_00000061 ON t7(a);
  0|0|0|SEARCH TABLE t7 USING INDEX t7_idx_00000061 (a=?) 
  0|0|0|SEARCH TABLE t7 USING INDEX t7_idx_00000062 (b=?)
}

# rowid terms.
#
do_setup_rec_test $tn.13.1 {
  CREATE TABLE t8(a, b);
} {
  SELECT * FROM t8 WHERE rowid=?
} {
  (no new indexes)
  0|0|0|SEARCH TABLE t8 USING INTEGER PRIMARY KEY (rowid=?)
}
do_setup_rec_test $tn.13.2 {
  CREATE TABLE t8(a, b);
} {
  SELECT * FROM t8 ORDER BY rowid
} {
  (no new indexes)
  0|0|0|SCAN TABLE t8
}
do_setup_rec_test $tn.13.3 {
  CREATE TABLE t8(a, b);
} {
  SELECT * FROM t8 WHERE a=? ORDER BY rowid
} {
  CREATE INDEX t8_idx_00000061 ON t8(a); 
  0|0|0|SEARCH TABLE t8 USING INDEX t8_idx_00000061 (a=?)
}

# Triggers
#
do_setup_rec_test $tn.14 {
  CREATE TABLE t9(a, b, c);
  CREATE TABLE t10(a, b, c);
  CREATE TRIGGER t9t AFTER INSERT ON t9 BEGIN
    UPDATE t10 SET a=new.a WHERE b = new.b;
  END;
} {
  INSERT INTO t9 VALUES(?, ?, ?);
} {
  CREATE INDEX t10_idx_00000062 ON t10(b); 
  0|0|0|SEARCH TABLE t10 USING INDEX t10_idx_00000062 (b=?)
}

do_setup_rec_test $tn.15 {
  CREATE TABLE t1(a, b);
  CREATE TABLE t2(c, d);

  WITH s(i) AS ( VALUES(1) UNION ALL SELECT i+1 FROM s WHERE i<100)
  INSERT INTO t1 SELECT (i-1)/50, (i-1)/20 FROM s;

  WITH s(i) AS ( VALUES(1) UNION ALL SELECT i+1 FROM s WHERE i<100)
  INSERT INTO t2 SELECT (i-1)/20, (i-1)/5 FROM s;
} {
  SELECT * FROM t2, t1 WHERE b=? AND d=? AND t2.rowid=t1.rowid
} {
  CREATE INDEX t2_idx_00000064 ON t2(d);
  0|0|0|SEARCH TABLE t2 USING INDEX t2_idx_00000064 (d=?) 
  0|1|1|SEARCH TABLE t1 USING INTEGER PRIMARY KEY (rowid=?)
}

do_setup_rec_test $tn.16 {
  CREATE TABLE t1(a, b);
} {
  SELECT * FROM t1 WHERE b IS NOT NULL;
} {
  (no new indexes)
  0|0|0|SCAN TABLE t1
}

}

proc do_candidates_test {tn sql res} {
  set res [squish [string trim $res]]

  set expert [sqlite3_expert_new db]
  $expert sql $sql
  $expert analyze

  set candidates [squish [string trim [$expert report 0 candidates]]]
  $expert destroy

  uplevel [list do_test $tn [list set {} $candidates] $res]
}


reset_db
do_execsql_test 3.0 {
  CREATE TABLE t1(a, b);
  CREATE TABLE t2(c, d);

  WITH s(i) AS ( VALUES(1) UNION ALL SELECT i+1 FROM s WHERE i<100)
  INSERT INTO t1 SELECT (i-1)/50, (i-1)/20 FROM s;

  WITH s(i) AS ( VALUES(1) UNION ALL SELECT i+1 FROM s WHERE i<100)
  INSERT INTO t2 SELECT (i-1)/20, (i-1)/5 FROM s;
}
do_candidates_test 3.1 {
  SELECT * FROM t1,t2 WHERE (b=? OR a=?) AND (c=? OR d=?)
} {
  CREATE INDEX t1_idx_00000062 ON t1(b); -- stat1: 100 20 
  CREATE INDEX t1_idx_00000061 ON t1(a); -- stat1: 100 50 
  CREATE INDEX t2_idx_00000063 ON t2(c); -- stat1: 100 20 
  CREATE INDEX t2_idx_00000064 ON t2(d); -- stat1: 100 5
}

do_candidates_test 3.2 {
  SELECT * FROM t1,t2 WHERE a=? AND b=? AND c=? AND d=?
} {
  CREATE INDEX t1_idx_000123a7 ON t1(a, b); -- stat1: 100 50 17
  CREATE INDEX t2_idx_0001295b ON t2(c, d); -- stat1: 100 20 5
}

do_execsql_test 3.2 {
  CREATE INDEX t1_idx_00000061 ON t1(a); -- stat1: 100 50 
  CREATE INDEX t1_idx_00000062 ON t1(b); -- stat1: 100 20 
  CREATE INDEX t1_idx_000123a7 ON t1(a, b); -- stat1: 100 50 16

  CREATE INDEX t2_idx_00000063 ON t2(c); -- stat1: 100 20 
  CREATE INDEX t2_idx_00000064 ON t2(d); -- stat1: 100 5
  CREATE INDEX t2_idx_0001295b ON t2(c, d); -- stat1: 100 20 5

  ANALYZE;
  SELECT * FROM sqlite_stat1 ORDER BY 1, 2;
} {
  t1 t1_idx_00000061 {100 50} 
  t1 t1_idx_00000062 {100 20}
  t1 t1_idx_000123a7 {100 50 17}
  t2 t2_idx_00000063 {100 20} 
  t2 t2_idx_00000064 {100 5} 
  t2 t2_idx_0001295b {100 20 5}
}


finish_test

/*
** 2017 April 09
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
*/
#include "sqlite3expert.h"
#include <assert.h>
#include <string.h>
#include <stdio.h>

#ifndef SQLITE_OMIT_VIRTUALTABLE 

typedef sqlite3_int64 i64;
typedef sqlite3_uint64 u64;

typedef struct IdxColumn IdxColumn;
typedef struct IdxConstraint IdxConstraint;
typedef struct IdxScan IdxScan;
typedef struct IdxStatement IdxStatement;
typedef struct IdxTable IdxTable;
typedef struct IdxWrite IdxWrite;

#define STRLEN  (int)strlen

/*
** A temp table name that we assume no user database will actually use.
** If this assumption proves incorrect triggers on the table with the
** conflicting name will be ignored.
*/
#define UNIQUE_TABLE_NAME "t592690916721053953805701627921227776"

/*
** A single constraint. Equivalent to either "col = ?" or "col < ?" (or
** any other type of single-ended range constraint on a column).
**
** pLink:
**   Used to temporarily link IdxConstraint objects into lists while
**   creating candidate indexes.
*/
struct IdxConstraint {
  char *zColl;                    /* Collation sequence */
  int bRange;                     /* True for range, false for eq */
  int iCol;                       /* Constrained table column */
  int bFlag;                      /* Used by idxFindCompatible() */
  int bDesc;                      /* True if ORDER BY <expr> DESC */
  IdxConstraint *pNext;           /* Next constraint in pEq or pRange list */
  IdxConstraint *pLink;           /* See above */
};

/*
** A single scan of a single table.
*/
struct IdxScan {
  IdxTable *pTab;                 /* Associated table object */
  int iDb;                        /* Database containing table zTable */
  i64 covering;                   /* Mask of columns required for cov. index */
  IdxConstraint *pOrder;          /* ORDER BY columns */
  IdxConstraint *pEq;             /* List of == constraints */
  IdxConstraint *pRange;          /* List of < constraints */
  IdxScan *pNextScan;             /* Next IdxScan object for same analysis */
};

/*
** Information regarding a single database table. Extracted from 
** "PRAGMA table_info" by function idxGetTableInfo().
*/
struct IdxColumn {
  char *zName;
  char *zColl;
  int iPk;
};
struct IdxTable {
  int nCol;
  char *zName;                    /* Table name */
  IdxColumn *aCol;
  IdxTable *pNext;                /* Next table in linked list of all tables */
};

/*
** An object of the following type is created for each unique table/write-op
** seen. The objects are stored in a singly-linked list beginning at
** sqlite3expert.pWrite.
*/
struct IdxWrite {
  IdxTable *pTab;
  int eOp;                        /* SQLITE_UPDATE, DELETE or INSERT */
  IdxWrite *pNext;
};

/*
** Each statement being analyzed is represented by an instance of this
** structure.
*/
struct IdxStatement {
  int iId;                        /* Statement number */
  char *zSql;                     /* SQL statement */
  char *zIdx;                     /* Indexes */
  char *zEQP;                     /* Plan */
  IdxStatement *pNext;
};


/*
** A hash table for storing strings. With space for a payload string
** with each entry. Methods are:
**
**   idxHashInit()
**   idxHashClear()
**   idxHashAdd()
**   idxHashSearch()
*/
#define IDX_HASH_SIZE 1023
typedef struct IdxHashEntry IdxHashEntry;
typedef struct IdxHash IdxHash;
struct IdxHashEntry {
  char *zKey;                     /* nul-terminated key */
  char *zVal;                     /* nul-terminated value string */
  char *zVal2;                    /* nul-terminated value string 2 */
  IdxHashEntry *pHashNext;        /* Next entry in same hash bucket */
  IdxHashEntry *pNext;            /* Next entry in hash */
};
struct IdxHash {
  IdxHashEntry *pFirst;
  IdxHashEntry *aHash[IDX_HASH_SIZE];
};

/*
** sqlite3expert object.
*/
struct sqlite3expert {
  int iSample;                    /* Percentage of tables to sample for stat1 */
  sqlite3 *db;                    /* User database */
  sqlite3 *dbm;                   /* In-memory db for this analysis */
  sqlite3 *dbv;                   /* Vtab schema for this analysis */
  IdxTable *pTable;               /* List of all IdxTable objects */
  IdxScan *pScan;                 /* List of scan objects */
  IdxWrite *pWrite;               /* List of write objects */
  IdxStatement *pStatement;       /* List of IdxStatement objects */
  int bRun;                       /* True once analysis has run */
  char **pzErrmsg;
  int rc;                         /* Error code from whereinfo hook */
  IdxHash hIdx;                   /* Hash containing all candidate indexes */
  char *zCandidates;              /* For EXPERT_REPORT_CANDIDATES */
};


/*
** Allocate and return nByte bytes of zeroed memory using sqlite3_malloc(). 
** If the allocation fails, set *pRc to SQLITE_NOMEM and return NULL.
*/
static void *idxMalloc(int *pRc, int nByte){
  void *pRet;
  assert( *pRc==SQLITE_OK );
  assert( nByte>0 );
  pRet = sqlite3_malloc(nByte);
  if( pRet ){
    memset(pRet, 0, nByte);
  }else{
    *pRc = SQLITE_NOMEM;
  }
  return pRet;
}

/*
** Initialize an IdxHash hash table.
*/
static void idxHashInit(IdxHash *pHash){
  memset(pHash, 0, sizeof(IdxHash));
}

/*
** Reset an IdxHash hash table.
*/
static void idxHashClear(IdxHash *pHash){
  int i;
  for(i=0; i<IDX_HASH_SIZE; i++){
    IdxHashEntry *pEntry;
    IdxHashEntry *pNext;
    for(pEntry=pHash->aHash[i]; pEntry; pEntry=pNext){
      pNext = pEntry->pHashNext;
      sqlite3_free(pEntry->zVal2);
      sqlite3_free(pEntry);
    }
  }
  memset(pHash, 0, sizeof(IdxHash));
}

/*
** Return the index of the hash bucket that the string specified by the
** arguments to this function belongs.
*/
static int idxHashString(const char *z, int n){
  unsigned int ret = 0;
  int i;
  for(i=0; i<n; i++){
    ret += (ret<<3) + (unsigned char)(z[i]);
  }
  return (int)(ret % IDX_HASH_SIZE);
}

/*
** If zKey is already present in the hash table, return non-zero and do
** nothing. Otherwise, add an entry with key zKey and payload string zVal to
** the hash table passed as the second argument. 
*/
static int idxHashAdd(
  int *pRc, 
  IdxHash *pHash, 
  const char *zKey,
  const char *zVal
){
  int nKey = STRLEN(zKey);
  int iHash = idxHashString(zKey, nKey);
  int nVal = (zVal ? STRLEN(zVal) : 0);
  IdxHashEntry *pEntry;
  assert( iHash>=0 );
  for(pEntry=pHash->aHash[iHash]; pEntry; pEntry=pEntry->pHashNext){
    if( STRLEN(pEntry->zKey)==nKey && 0==memcmp(pEntry->zKey, zKey, nKey) ){
      return 1;
    }
  }
  pEntry = idxMalloc(pRc, sizeof(IdxHashEntry) + nKey+1 + nVal+1);
  if( pEntry ){
    pEntry->zKey = (char*)&pEntry[1];
    memcpy(pEntry->zKey, zKey, nKey);
    if( zVal ){
      pEntry->zVal = &pEntry->zKey[nKey+1];
      memcpy(pEntry->zVal, zVal, nVal);
    }
    pEntry->pHashNext = pHash->aHash[iHash];
    pHash->aHash[iHash] = pEntry;

    pEntry->pNext = pHash->pFirst;
    pHash->pFirst = pEntry;
  }
  return 0;
}

/*
** If zKey/nKey is present in the hash table, return a pointer to the 
** hash-entry object.
*/
static IdxHashEntry *idxHashFind(IdxHash *pHash, const char *zKey, int nKey){
  int iHash;
  IdxHashEntry *pEntry;
  if( nKey<0 ) nKey = STRLEN(zKey);
  iHash = idxHashString(zKey, nKey);
  assert( iHash>=0 );
  for(pEntry=pHash->aHash[iHash]; pEntry; pEntry=pEntry->pHashNext){
    if( STRLEN(pEntry->zKey)==nKey && 0==memcmp(pEntry->zKey, zKey, nKey) ){
      return pEntry;
    }
  }
  return 0;
}

/*
** If the hash table contains an entry with a key equal to the string
** passed as the final two arguments to this function, return a pointer
** to the payload string. Otherwise, if zKey/nKey is not present in the
** hash table, return NULL.
*/
static const char *idxHashSearch(IdxHash *pHash, const char *zKey, int nKey){
  IdxHashEntry *pEntry = idxHashFind(pHash, zKey, nKey);
  if( pEntry ) return pEntry->zVal;
  return 0;
}

/*
** Allocate and return a new IdxConstraint object. Set the IdxConstraint.zColl
** variable to point to a copy of nul-terminated string zColl.
*/
static IdxConstraint *idxNewConstraint(int *pRc, const char *zColl){
  IdxConstraint *pNew;
  int nColl = STRLEN(zColl);

  assert( *pRc==SQLITE_OK );
  pNew = (IdxConstraint*)idxMalloc(pRc, sizeof(IdxConstraint) * nColl + 1);
  if( pNew ){
    pNew->zColl = (char*)&pNew[1];
    memcpy(pNew->zColl, zColl, nColl+1);
  }
  return pNew;
}

/*
** An error associated with database handle db has just occurred. Pass
** the error message to callback function xOut.
*/
static void idxDatabaseError(
  sqlite3 *db,                    /* Database handle */
  char **pzErrmsg                 /* Write error here */
){
  *pzErrmsg = sqlite3_mprintf("%s", sqlite3_errmsg(db));
}

/*
** Prepare an SQL statement.
*/
static int idxPrepareStmt(
  sqlite3 *db,                    /* Database handle to compile against */
  sqlite3_stmt **ppStmt,          /* OUT: Compiled SQL statement */
  char **pzErrmsg,                /* OUT: sqlite3_malloc()ed error message */
  const char *zSql                /* SQL statement to compile */
){
  int rc = sqlite3_prepare_v2(db, zSql, -1, ppStmt, 0);
  if( rc!=SQLITE_OK ){
    *ppStmt = 0;
    idxDatabaseError(db, pzErrmsg);
  }
  return rc;
}

/*
** Prepare an SQL statement using the results of a printf() formatting.
*/
static int idxPrintfPrepareStmt(
  sqlite3 *db,                    /* Database handle to compile against */
  sqlite3_stmt **ppStmt,          /* OUT: Compiled SQL statement */
  char **pzErrmsg,                /* OUT: sqlite3_malloc()ed error message */
  const char *zFmt,               /* printf() format of SQL statement */
  ...                             /* Trailing printf() arguments */
){
  va_list ap;
  int rc;
  char *zSql;
  va_start(ap, zFmt);
  zSql = sqlite3_vmprintf(zFmt, ap);
  if( zSql==0 ){
    rc = SQLITE_NOMEM;
  }else{
    rc = idxPrepareStmt(db, ppStmt, pzErrmsg, zSql);
    sqlite3_free(zSql);
  }
  va_end(ap);
  return rc;
}


/*************************************************************************
** Beginning of virtual table implementation.
*/
typedef struct ExpertVtab ExpertVtab;
struct ExpertVtab {
  sqlite3_vtab base;
  IdxTable *pTab;
  sqlite3expert *pExpert;
};

typedef struct ExpertCsr ExpertCsr;
struct ExpertCsr {
  sqlite3_vtab_cursor base;
  sqlite3_stmt *pData;
};

static char *expertDequote(const char *zIn){
  int n = STRLEN(zIn);
  char *zRet = sqlite3_malloc(n);

  assert( zIn[0]=='\'' );
  assert( zIn[n-1]=='\'' );

  if( zRet ){
    int iOut = 0;
    int iIn = 0;
    for(iIn=1; iIn<(n-1); iIn++){
      if( zIn[iIn]=='\'' ){
        assert( zIn[iIn+1]=='\'' );
        iIn++;
      }
      zRet[iOut++] = zIn[iIn];
    }
    zRet[iOut] = '\0';
  }

  return zRet;
}

/* 
** This function is the implementation of both the xConnect and xCreate
** methods of the r-tree virtual table.
**
**   argv[0]   -> module name
**   argv[1]   -> database name
**   argv[2]   -> table name
**   argv[...] -> column names...
*/
static int expertConnect(
  sqlite3 *db,
  void *pAux,
  int argc, const char *const*argv,
  sqlite3_vtab **ppVtab,
  char **pzErr
){
  sqlite3expert *pExpert = (sqlite3expert*)pAux;
  ExpertVtab *p = 0;
  int rc;

  if( argc!=4 ){
    *pzErr = sqlite3_mprintf("internal error!");
    rc = SQLITE_ERROR;
  }else{
    char *zCreateTable = expertDequote(argv[3]);
    if( zCreateTable ){
      rc = sqlite3_declare_vtab(db, zCreateTable);
      if( rc==SQLITE_OK ){
        p = idxMalloc(&rc, sizeof(ExpertVtab));
      }
      if( rc==SQLITE_OK ){
        p->pExpert = pExpert;
        p->pTab = pExpert->pTable;
        assert( sqlite3_stricmp(p->pTab->zName, argv[2])==0 );
      }
      sqlite3_free(zCreateTable);
    }else{
      rc = SQLITE_NOMEM;
    }
  }

  *ppVtab = (sqlite3_vtab*)p;
  return rc;
}

static int expertDisconnect(sqlite3_vtab *pVtab){
  ExpertVtab *p = (ExpertVtab*)pVtab;
  sqlite3_free(p);
  return SQLITE_OK;
}

static int expertBestIndex(sqlite3_vtab *pVtab, sqlite3_index_info *pIdxInfo){
  ExpertVtab *p = (ExpertVtab*)pVtab;
  int rc = SQLITE_OK;
  int n = 0;
  IdxScan *pScan;
  const int opmask = 
    SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_GT |
    SQLITE_INDEX_CONSTRAINT_LT | SQLITE_INDEX_CONSTRAINT_GE |
    SQLITE_INDEX_CONSTRAINT_LE;

  pScan = idxMalloc(&rc, sizeof(IdxScan));
  if( pScan ){
    int i;

    /* Link the new scan object into the list */
    pScan->pTab = p->pTab;
    pScan->pNextScan = p->pExpert->pScan;
    p->pExpert->pScan = pScan;

    /* Add the constraints to the IdxScan object */
    for(i=0; i<pIdxInfo->nConstraint; i++){
      struct sqlite3_index_constraint *pCons = &pIdxInfo->aConstraint[i];
      if( pCons->usable 
       && pCons->iColumn>=0 
       && p->pTab->aCol[pCons->iColumn].iPk==0
       && (pCons->op & opmask) 
      ){
        IdxConstraint *pNew;
        const char *zColl = sqlite3_vtab_collation(pIdxInfo, i);
        pNew = idxNewConstraint(&rc, zColl);
        if( pNew ){
          pNew->iCol = pCons->iColumn;
          if( pCons->op==SQLITE_INDEX_CONSTRAINT_EQ ){
            pNew->pNext = pScan->pEq;
            pScan->pEq = pNew;
          }else{
            pNew->bRange = 1;
            pNew->pNext = pScan->pRange;
            pScan->pRange = pNew;
          }
        }
        n++;
        pIdxInfo->aConstraintUsage[i].argvIndex = n;
      }
    }

    /* Add the ORDER BY to the IdxScan object */
    for(i=pIdxInfo->nOrderBy-1; i>=0; i--){
      int iCol = pIdxInfo->aOrderBy[i].iColumn;
      if( iCol>=0 ){
        IdxConstraint *pNew = idxNewConstraint(&rc, p->pTab->aCol[iCol].zColl);
        if( pNew ){
          pNew->iCol = iCol;
          pNew->bDesc = pIdxInfo->aOrderBy[i].desc;
          pNew->pNext = pScan->pOrder;
          pNew->pLink = pScan->pOrder;
          pScan->pOrder = pNew;
          n++;
        }
      }
    }
  }

  pIdxInfo->estimatedCost = 1000000.0 / (n+1);
  return rc;
}

static int expertUpdate(
  sqlite3_vtab *pVtab, 
  int nData, 
  sqlite3_value **azData, 
  sqlite_int64 *pRowid
){
  (void)pVtab;
  (void)nData;
  (void)azData;
  (void)pRowid;
  return SQLITE_OK;
}

/* 
** Virtual table module xOpen method.
*/
static int expertOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
  int rc = SQLITE_OK;
  ExpertCsr *pCsr;
  (void)pVTab;
  pCsr = idxMalloc(&rc, sizeof(ExpertCsr));
  *ppCursor = (sqlite3_vtab_cursor*)pCsr;
  return rc;
}

/* 
** Virtual table module xClose method.
*/
static int expertClose(sqlite3_vtab_cursor *cur){
  ExpertCsr *pCsr = (ExpertCsr*)cur;
  sqlite3_finalize(pCsr->pData);
  sqlite3_free(pCsr);
  return SQLITE_OK;
}

/*
** Virtual table module xEof method.
**
** Return non-zero if the cursor does not currently point to a valid 
** record (i.e if the scan has finished), or zero otherwise.
*/
static int expertEof(sqlite3_vtab_cursor *cur){
  ExpertCsr *pCsr = (ExpertCsr*)cur;
  return pCsr->pData==0;
}

/* 
** Virtual table module xNext method.
*/
static int expertNext(sqlite3_vtab_cursor *cur){
  ExpertCsr *pCsr = (ExpertCsr*)cur;
  int rc = SQLITE_OK;

  assert( pCsr->pData );
  rc = sqlite3_step(pCsr->pData);
  if( rc!=SQLITE_ROW ){
    rc = sqlite3_finalize(pCsr->pData);
    pCsr->pData = 0;
  }else{
    rc = SQLITE_OK;
  }

  return rc;
}

/* 
** Virtual table module xRowid method.
*/
static int expertRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
  (void)cur;
  *pRowid = 0;
  return SQLITE_OK;
}

/* 
** Virtual table module xColumn method.
*/
static int expertColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){
  ExpertCsr *pCsr = (ExpertCsr*)cur;
  sqlite3_value *pVal;
  pVal = sqlite3_column_value(pCsr->pData, i);
  if( pVal ){
    sqlite3_result_value(ctx, pVal);
  }
  return SQLITE_OK;
}

/* 
** Virtual table module xFilter method.
*/
static int expertFilter(
  sqlite3_vtab_cursor *cur, 
  int idxNum, const char *idxStr,
  int argc, sqlite3_value **argv
){
  ExpertCsr *pCsr = (ExpertCsr*)cur;
  ExpertVtab *pVtab = (ExpertVtab*)(cur->pVtab);
  sqlite3expert *pExpert = pVtab->pExpert;
  int rc;

  (void)idxNum;
  (void)idxStr;
  (void)argc;
  (void)argv;
  rc = sqlite3_finalize(pCsr->pData);
  pCsr->pData = 0;
  if( rc==SQLITE_OK ){
    rc = idxPrintfPrepareStmt(pExpert->db, &pCsr->pData, &pVtab->base.zErrMsg,
        "SELECT * FROM main.%Q WHERE sample()", pVtab->pTab->zName
    );
  }

  if( rc==SQLITE_OK ){
    rc = expertNext(cur);
  }
  return rc;
}

static int idxRegisterVtab(sqlite3expert *p){
  static sqlite3_module expertModule = {
    2,                            /* iVersion */
    expertConnect,                /* xCreate - create a table */
    expertConnect,                /* xConnect - connect to an existing table */
    expertBestIndex,              /* xBestIndex - Determine search strategy */
    expertDisconnect,             /* xDisconnect - Disconnect from a table */
    expertDisconnect,             /* xDestroy - Drop a table */
    expertOpen,                   /* xOpen - open a cursor */
    expertClose,                  /* xClose - close a cursor */
    expertFilter,                 /* xFilter - configure scan constraints */
    expertNext,                   /* xNext - advance a cursor */
    expertEof,                    /* xEof */
    expertColumn,                 /* xColumn - read data */
    expertRowid,                  /* xRowid - read data */
    expertUpdate,                 /* xUpdate - write data */
    0,                            /* xBegin - begin transaction */
    0,                            /* xSync - sync transaction */
    0,                            /* xCommit - commit transaction */
    0,                            /* xRollback - rollback transaction */
    0,                            /* xFindFunction - function overloading */
    0,                            /* xRename - rename the table */
    0,                            /* xSavepoint */
    0,                            /* xRelease */
    0,                            /* xRollbackTo */
  };

  return sqlite3_create_module(p->dbv, "expert", &expertModule, (void*)p);
}
/*
** End of virtual table implementation.
*************************************************************************/
/*
** Finalize SQL statement pStmt. If (*pRc) is SQLITE_OK when this function
** is called, set it to the return value of sqlite3_finalize() before
** returning. Otherwise, discard the sqlite3_finalize() return value.
*/
static void idxFinalize(int *pRc, sqlite3_stmt *pStmt){
  int rc = sqlite3_finalize(pStmt);
  if( *pRc==SQLITE_OK ) *pRc = rc;
}

/*
** Attempt to allocate an IdxTable structure corresponding to table zTab
** in the main database of connection db. If successful, set (*ppOut) to
** point to the new object and return SQLITE_OK. Otherwise, return an
** SQLite error code and set (*ppOut) to NULL. In this case *pzErrmsg may be
** set to point to an error string.
**
** It is the responsibility of the caller to eventually free either the
** IdxTable object or error message using sqlite3_free().
*/
static int idxGetTableInfo(
  sqlite3 *db,                    /* Database connection to read details from */
  const char *zTab,               /* Table name */
  IdxTable **ppOut,               /* OUT: New object (if successful) */
  char **pzErrmsg                 /* OUT: Error message (if not) */
){
  sqlite3_stmt *p1 = 0;
  int nCol = 0;
  int nTab = STRLEN(zTab);
  int nByte = sizeof(IdxTable) + nTab + 1;
  IdxTable *pNew = 0;
  int rc, rc2;
  char *pCsr = 0;

  rc = idxPrintfPrepareStmt(db, &p1, pzErrmsg, "PRAGMA table_info=%Q", zTab);
  while( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(p1) ){
    const char *zCol = (const char*)sqlite3_column_text(p1, 1);
    nByte += 1 + STRLEN(zCol);
    rc = sqlite3_table_column_metadata(
        db, "main", zTab, zCol, 0, &zCol, 0, 0, 0
    );
    nByte += 1 + STRLEN(zCol);
    nCol++;
  }
  rc2 = sqlite3_reset(p1);
  if( rc==SQLITE_OK ) rc = rc2;

  nByte += sizeof(IdxColumn) * nCol;
  if( rc==SQLITE_OK ){
    pNew = idxMalloc(&rc, nByte);
  }
  if( rc==SQLITE_OK ){
    pNew->aCol = (IdxColumn*)&pNew[1];
    pNew->nCol = nCol;
    pCsr = (char*)&pNew->aCol[nCol];
  }

  nCol = 0;
  while( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(p1) ){
    const char *zCol = (const char*)sqlite3_column_text(p1, 1);
    int nCopy = STRLEN(zCol) + 1;
    pNew->aCol[nCol].zName = pCsr;
    pNew->aCol[nCol].iPk = sqlite3_column_int(p1, 5);
    memcpy(pCsr, zCol, nCopy);
    pCsr += nCopy;

    rc = sqlite3_table_column_metadata(
        db, "main", zTab, zCol, 0, &zCol, 0, 0, 0
    );
    if( rc==SQLITE_OK ){
      nCopy = STRLEN(zCol) + 1;
      pNew->aCol[nCol].zColl = pCsr;
      memcpy(pCsr, zCol, nCopy);
      pCsr += nCopy;
    }

    nCol++;
  }
  idxFinalize(&rc, p1);

  if( rc!=SQLITE_OK ){
    sqlite3_free(pNew);
    pNew = 0;
  }else{
    pNew->zName = pCsr;
    memcpy(pNew->zName, zTab, nTab+1);
  }

  *ppOut = pNew;
  return rc;
}

/*
** This function is a no-op if *pRc is set to anything other than 
** SQLITE_OK when it is called.
**
** If *pRc is initially set to SQLITE_OK, then the text specified by
** the printf() style arguments is appended to zIn and the result returned
** in a buffer allocated by sqlite3_malloc(). sqlite3_free() is called on
** zIn before returning.
*/
static char *idxAppendText(int *pRc, char *zIn, const char *zFmt, ...){
  va_list ap;
  char *zAppend = 0;
  char *zRet = 0;
  int nIn = zIn ? STRLEN(zIn) : 0;
  int nAppend = 0;
  va_start(ap, zFmt);
  if( *pRc==SQLITE_OK ){
    zAppend = sqlite3_vmprintf(zFmt, ap);
    if( zAppend ){
      nAppend = STRLEN(zAppend);
      zRet = (char*)sqlite3_malloc(nIn + nAppend + 1);
    }
    if( zAppend && zRet ){
      if( nIn ) memcpy(zRet, zIn, nIn);
      memcpy(&zRet[nIn], zAppend, nAppend+1);
    }else{
      sqlite3_free(zRet);
      zRet = 0;
      *pRc = SQLITE_NOMEM;
    }
    sqlite3_free(zAppend);
    sqlite3_free(zIn);
  }
  va_end(ap);
  return zRet;
}

/*
** Return true if zId must be quoted in order to use it as an SQL
** identifier, or false otherwise.
*/
static int idxIdentifierRequiresQuotes(const char *zId){
  int i;
  for(i=0; zId[i]; i++){
    if( !(zId[i]=='_')
     && !(zId[i]>='0' && zId[i]<='9')
     && !(zId[i]>='a' && zId[i]<='z')
     && !(zId[i]>='A' && zId[i]<='Z')
    ){
      return 1;
    }
  }
  return 0;
}

/*
** This function appends an index column definition suitable for constraint
** pCons to the string passed as zIn and returns the result.
*/
static char *idxAppendColDefn(
  int *pRc,                       /* IN/OUT: Error code */
  char *zIn,                      /* Column defn accumulated so far */
  IdxTable *pTab,                 /* Table index will be created on */
  IdxConstraint *pCons
){
  char *zRet = zIn;
  IdxColumn *p = &pTab->aCol[pCons->iCol];
  if( zRet ) zRet = idxAppendText(pRc, zRet, ", ");

  if( idxIdentifierRequiresQuotes(p->zName) ){
    zRet = idxAppendText(pRc, zRet, "%Q", p->zName);
  }else{
    zRet = idxAppendText(pRc, zRet, "%s", p->zName);
  }

  if( sqlite3_stricmp(p->zColl, pCons->zColl) ){
    if( idxIdentifierRequiresQuotes(pCons->zColl) ){
      zRet = idxAppendText(pRc, zRet, " COLLATE %Q", pCons->zColl);
    }else{
      zRet = idxAppendText(pRc, zRet, " COLLATE %s", pCons->zColl);
    }
  }

  if( pCons->bDesc ){
    zRet = idxAppendText(pRc, zRet, " DESC");
  }
  return zRet;
}

/*
** Search database dbm for an index compatible with the one idxCreateFromCons()
** would create from arguments pScan, pEq and pTail. If no error occurs and 
** such an index is found, return non-zero. Or, if no such index is found,
** return zero.
**
** If an error occurs, set *pRc to an SQLite error code and return zero.
*/
static int idxFindCompatible(
  int *pRc,                       /* OUT: Error code */
  sqlite3* dbm,                   /* Database to search */
  IdxScan *pScan,                 /* Scan for table to search for index on */
  IdxConstraint *pEq,             /* List of == constraints */
  IdxConstraint *pTail            /* List of range constraints */
){
  const char *zTbl = pScan->pTab->zName;
  sqlite3_stmt *pIdxList = 0;
  IdxConstraint *pIter;
  int nEq = 0;                    /* Number of elements in pEq */
  int rc;

  /* Count the elements in list pEq */
  for(pIter=pEq; pIter; pIter=pIter->pLink) nEq++;

  rc = idxPrintfPrepareStmt(dbm, &pIdxList, 0, "PRAGMA index_list=%Q", zTbl);
  while( rc==SQLITE_OK && sqlite3_step(pIdxList)==SQLITE_ROW ){
    int bMatch = 1;
    IdxConstraint *pT = pTail;
    sqlite3_stmt *pInfo = 0;
    const char *zIdx = (const char*)sqlite3_column_text(pIdxList, 1);

    /* Zero the IdxConstraint.bFlag values in the pEq list */
    for(pIter=pEq; pIter; pIter=pIter->pLink) pIter->bFlag = 0;

    rc = idxPrintfPrepareStmt(dbm, &pInfo, 0, "PRAGMA index_xInfo=%Q", zIdx);
    while( rc==SQLITE_OK && sqlite3_step(pInfo)==SQLITE_ROW ){
      int iIdx = sqlite3_column_int(pInfo, 0);
      int iCol = sqlite3_column_int(pInfo, 1);
      const char *zColl = (const char*)sqlite3_column_text(pInfo, 4);

      if( iIdx<nEq ){
        for(pIter=pEq; pIter; pIter=pIter->pLink){
          if( pIter->bFlag ) continue;
          if( pIter->iCol!=iCol ) continue;
          if( sqlite3_stricmp(pIter->zColl, zColl) ) continue;
          pIter->bFlag = 1;
          break;
        }
        if( pIter==0 ){
          bMatch = 0;
          break;
        }
      }else{
        if( pT ){
          if( pT->iCol!=iCol || sqlite3_stricmp(pT->zColl, zColl) ){
            bMatch = 0;
            break;
          }
          pT = pT->pLink;
        }
      }
    }
    idxFinalize(&rc, pInfo);

    if( rc==SQLITE_OK && bMatch ){
      sqlite3_finalize(pIdxList);
      return 1;
    }
  }
  idxFinalize(&rc, pIdxList);

  *pRc = rc;
  return 0;
}

static int idxCreateFromCons(
  sqlite3expert *p,
  IdxScan *pScan,
  IdxConstraint *pEq, 
  IdxConstraint *pTail
){
  sqlite3 *dbm = p->dbm;
  int rc = SQLITE_OK;
  if( (pEq || pTail) && 0==idxFindCompatible(&rc, dbm, pScan, pEq, pTail) ){
    IdxTable *pTab = pScan->pTab;
    char *zCols = 0;
    char *zIdx = 0;
    IdxConstraint *pCons;
    unsigned int h = 0;
    const char *zFmt;

    for(pCons=pEq; pCons; pCons=pCons->pLink){
      zCols = idxAppendColDefn(&rc, zCols, pTab, pCons);
    }
    for(pCons=pTail; pCons; pCons=pCons->pLink){
      zCols = idxAppendColDefn(&rc, zCols, pTab, pCons);
    }

    if( rc==SQLITE_OK ){
      /* Hash the list of columns to come up with a name for the index */
      const char *zTable = pScan->pTab->zName;
      char *zName;                /* Index name */
      int i;
      for(i=0; zCols[i]; i++){
        h += ((h<<3) + zCols[i]);
      }
      zName = sqlite3_mprintf("%s_idx_%08x", zTable, h);
      if( zName==0 ){ 
        rc = SQLITE_NOMEM;
      }else{
        if( idxIdentifierRequiresQuotes(zTable) ){
          zFmt = "CREATE INDEX '%q' ON %Q(%s)";
        }else{
          zFmt = "CREATE INDEX %s ON %s(%s)";
        }
        zIdx = sqlite3_mprintf(zFmt, zName, zTable, zCols);
        if( !zIdx ){
          rc = SQLITE_NOMEM;
        }else{
          rc = sqlite3_exec(dbm, zIdx, 0, 0, p->pzErrmsg);
          idxHashAdd(&rc, &p->hIdx, zName, zIdx);
        }
        sqlite3_free(zName);
        sqlite3_free(zIdx);
      }
    }

    sqlite3_free(zCols);
  }
  return rc;
}

/*
** Return true if list pList (linked by IdxConstraint.pLink) contains
** a constraint compatible with *p. Otherwise return false.
*/
static int idxFindConstraint(IdxConstraint *pList, IdxConstraint *p){
  IdxConstraint *pCmp;
  for(pCmp=pList; pCmp; pCmp=pCmp->pLink){
    if( p->iCol==pCmp->iCol ) return 1;
  }
  return 0;
}

static int idxCreateFromWhere(
  sqlite3expert *p, 
  IdxScan *pScan,                 /* Create indexes for this scan */
  IdxConstraint *pTail            /* range/ORDER BY constraints for inclusion */
){
  IdxConstraint *p1 = 0;
  IdxConstraint *pCon;
  int rc;

  /* Gather up all the == constraints. */
  for(pCon=pScan->pEq; pCon; pCon=pCon->pNext){
    if( !idxFindConstraint(p1, pCon) && !idxFindConstraint(pTail, pCon) ){
      pCon->pLink = p1;
      p1 = pCon;
    }
  }

  /* Create an index using the == constraints collected above. And the
  ** range constraint/ORDER BY terms passed in by the caller, if any. */
  rc = idxCreateFromCons(p, pScan, p1, pTail);

  /* If no range/ORDER BY passed by the caller, create a version of the
  ** index for each range constraint.  */
  if( pTail==0 ){
    for(pCon=pScan->pRange; rc==SQLITE_OK && pCon; pCon=pCon->pNext){
      assert( pCon->pLink==0 );
      if( !idxFindConstraint(p1, pCon) && !idxFindConstraint(pTail, pCon) ){
        rc = idxCreateFromCons(p, pScan, p1, pCon);
      }
    }
  }

  return rc;
}

/*
** Create candidate indexes in database [dbm] based on the data in 
** linked-list pScan.
*/
static int idxCreateCandidates(sqlite3expert *p){
  int rc = SQLITE_OK;
  IdxScan *pIter;

  for(pIter=p->pScan; pIter && rc==SQLITE_OK; pIter=pIter->pNextScan){
    rc = idxCreateFromWhere(p, pIter, 0);
    if( rc==SQLITE_OK && pIter->pOrder ){
      rc = idxCreateFromWhere(p, pIter, pIter->pOrder);
    }
  }

  return rc;
}

/*
** Free all elements of the linked list starting at pConstraint.
*/
static void idxConstraintFree(IdxConstraint *pConstraint){
  IdxConstraint *pNext;
  IdxConstraint *p;

  for(p=pConstraint; p; p=pNext){
    pNext = p->pNext;
    sqlite3_free(p);
  }
}

/*
** Free all elements of the linked list starting from pScan up until pLast
** (pLast is not freed).
*/
static void idxScanFree(IdxScan *pScan, IdxScan *pLast){
  IdxScan *p;
  IdxScan *pNext;
  for(p=pScan; p!=pLast; p=pNext){
    pNext = p->pNextScan;
    idxConstraintFree(p->pOrder);
    idxConstraintFree(p->pEq);
    idxConstraintFree(p->pRange);
    sqlite3_free(p);
  }
}

/*
** Free all elements of the linked list starting from pStatement up 
** until pLast (pLast is not freed).
*/
static void idxStatementFree(IdxStatement *pStatement, IdxStatement *pLast){
  IdxStatement *p;
  IdxStatement *pNext;
  for(p=pStatement; p!=pLast; p=pNext){
    pNext = p->pNext;
    sqlite3_free(p->zEQP);
    sqlite3_free(p->zIdx);
    sqlite3_free(p);
  }
}

/*
** Free the linked list of IdxTable objects starting at pTab.
*/
static void idxTableFree(IdxTable *pTab){
  IdxTable *pIter;
  IdxTable *pNext;
  for(pIter=pTab; pIter; pIter=pNext){
    pNext = pIter->pNext;
    sqlite3_free(pIter);
  }
}

/*
** Free the linked list of IdxWrite objects starting at pTab.
*/
static void idxWriteFree(IdxWrite *pTab){
  IdxWrite *pIter;
  IdxWrite *pNext;
  for(pIter=pTab; pIter; pIter=pNext){
    pNext = pIter->pNext;
    sqlite3_free(pIter);
  }
}



/*
** This function is called after candidate indexes have been created. It
** runs all the queries to see which indexes they prefer, and populates
** IdxStatement.zIdx and IdxStatement.zEQP with the results.
*/
int idxFindIndexes(
  sqlite3expert *p,
  char **pzErr                         /* OUT: Error message (sqlite3_malloc) */
){
  IdxStatement *pStmt;
  sqlite3 *dbm = p->dbm;
  int rc = SQLITE_OK;

  IdxHash hIdx;
  idxHashInit(&hIdx);

  for(pStmt=p->pStatement; rc==SQLITE_OK && pStmt; pStmt=pStmt->pNext){
    IdxHashEntry *pEntry;
    sqlite3_stmt *pExplain = 0;
    idxHashClear(&hIdx);
    rc = idxPrintfPrepareStmt(dbm, &pExplain, pzErr,
        "EXPLAIN QUERY PLAN %s", pStmt->zSql
    );
    while( rc==SQLITE_OK && sqlite3_step(pExplain)==SQLITE_ROW ){
      int iSelectid = sqlite3_column_int(pExplain, 0);
      int iOrder = sqlite3_column_int(pExplain, 1);
      int iFrom = sqlite3_column_int(pExplain, 2);
      const char *zDetail = (const char*)sqlite3_column_text(pExplain, 3);
      int nDetail = STRLEN(zDetail);
      int i;

      for(i=0; i<nDetail; i++){
        const char *zIdx = 0;
        if( memcmp(&zDetail[i], " USING INDEX ", 13)==0 ){
          zIdx = &zDetail[i+13];
        }else if( memcmp(&zDetail[i], " USING COVERING INDEX ", 22)==0 ){
          zIdx = &zDetail[i+22];
        }
        if( zIdx ){
          const char *zSql;
          int nIdx = 0;
          while( zIdx[nIdx]!='\0' && (zIdx[nIdx]!=' ' || zIdx[nIdx+1]!='(') ){
            nIdx++;
          }
          zSql = idxHashSearch(&p->hIdx, zIdx, nIdx);
          if( zSql ){
            idxHashAdd(&rc, &hIdx, zSql, 0);
            if( rc ) goto find_indexes_out;
          }
          break;
        }
      }

      pStmt->zEQP = idxAppendText(&rc, pStmt->zEQP, "%d|%d|%d|%s\n", 
          iSelectid, iOrder, iFrom, zDetail
      );
    }

    for(pEntry=hIdx.pFirst; pEntry; pEntry=pEntry->pNext){
      pStmt->zIdx = idxAppendText(&rc, pStmt->zIdx, "%s;\n", pEntry->zKey);
    }

    idxFinalize(&rc, pExplain);
  }

 find_indexes_out:
  idxHashClear(&hIdx);
  return rc;
}

static int idxAuthCallback(
  void *pCtx,
  int eOp,
  const char *z3,
  const char *z4,
  const char *zDb,
  const char *zTrigger
){
  int rc = SQLITE_OK;
  (void)z4;
  (void)zTrigger;
  if( eOp==SQLITE_INSERT || eOp==SQLITE_UPDATE || eOp==SQLITE_DELETE ){
    if( sqlite3_stricmp(zDb, "main")==0 ){
      sqlite3expert *p = (sqlite3expert*)pCtx;
      IdxTable *pTab;
      for(pTab=p->pTable; pTab; pTab=pTab->pNext){
        if( 0==sqlite3_stricmp(z3, pTab->zName) ) break;
      }
      if( pTab ){
        IdxWrite *pWrite;
        for(pWrite=p->pWrite; pWrite; pWrite=pWrite->pNext){
          if( pWrite->pTab==pTab && pWrite->eOp==eOp ) break;
        }
        if( pWrite==0 ){
          pWrite = idxMalloc(&rc, sizeof(IdxWrite));
          if( rc==SQLITE_OK ){
            pWrite->pTab = pTab;
            pWrite->eOp = eOp;
            pWrite->pNext = p->pWrite;
            p->pWrite = pWrite;
          }
        }
      }
    }
  }
  return rc;
}

static int idxProcessOneTrigger(
  sqlite3expert *p, 
  IdxWrite *pWrite, 
  char **pzErr
){
  static const char *zInt = UNIQUE_TABLE_NAME;
  static const char *zDrop = "DROP TABLE " UNIQUE_TABLE_NAME;
  IdxTable *pTab = pWrite->pTab;
  const char *zTab = pTab->zName;
  const char *zSql = 
    "SELECT 'CREATE TEMP' || substr(sql, 7) FROM sqlite_master "
    "WHERE tbl_name = %Q AND type IN ('table', 'trigger') "
    "ORDER BY type;";
  sqlite3_stmt *pSelect = 0;
  int rc = SQLITE_OK;
  char *zWrite = 0;

  /* Create the table and its triggers in the temp schema */
  rc = idxPrintfPrepareStmt(p->db, &pSelect, pzErr, zSql, zTab, zTab);
  while( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pSelect) ){
    const char *zCreate = (const char*)sqlite3_column_text(pSelect, 0);
    rc = sqlite3_exec(p->dbv, zCreate, 0, 0, pzErr);
  }
  idxFinalize(&rc, pSelect);

  /* Rename the table in the temp schema to zInt */
  if( rc==SQLITE_OK ){
    char *z = sqlite3_mprintf("ALTER TABLE temp.%Q RENAME TO %Q", zTab, zInt);
    if( z==0 ){
      rc = SQLITE_NOMEM;
    }else{
      rc = sqlite3_exec(p->dbv, z, 0, 0, pzErr);
      sqlite3_free(z);
    }
  }

  switch( pWrite->eOp ){
    case SQLITE_INSERT: {
      int i;
      zWrite = idxAppendText(&rc, zWrite, "INSERT INTO %Q VALUES(", zInt);
      for(i=0; i<pTab->nCol; i++){
        zWrite = idxAppendText(&rc, zWrite, "%s?", i==0 ? "" : ", ");
      }
      zWrite = idxAppendText(&rc, zWrite, ")");
      break;
    }
    case SQLITE_UPDATE: {
      int i;
      zWrite = idxAppendText(&rc, zWrite, "UPDATE %Q SET ", zInt);
      for(i=0; i<pTab->nCol; i++){
        zWrite = idxAppendText(&rc, zWrite, "%s%Q=?", i==0 ? "" : ", ", 
            pTab->aCol[i].zName
        );
      }
      break;
    }
    default: {
      assert( pWrite->eOp==SQLITE_DELETE );
      if( rc==SQLITE_OK ){
        zWrite = sqlite3_mprintf("DELETE FROM %Q", zInt);
        if( zWrite==0 ) rc = SQLITE_NOMEM;
      }
    }
  }

  if( rc==SQLITE_OK ){
    sqlite3_stmt *pX = 0;
    rc = sqlite3_prepare_v2(p->dbv, zWrite, -1, &pX, 0);
    idxFinalize(&rc, pX);
    if( rc!=SQLITE_OK ){
      idxDatabaseError(p->dbv, pzErr);
    }
  }
  sqlite3_free(zWrite);

  if( rc==SQLITE_OK ){
    rc = sqlite3_exec(p->dbv, zDrop, 0, 0, pzErr);
  }

  return rc;
}

static int idxProcessTriggers(sqlite3expert *p, char **pzErr){
  int rc = SQLITE_OK;
  IdxWrite *pEnd = 0;
  IdxWrite *pFirst = p->pWrite;

  while( rc==SQLITE_OK && pFirst!=pEnd ){
    IdxWrite *pIter;
    for(pIter=pFirst; rc==SQLITE_OK && pIter!=pEnd; pIter=pIter->pNext){
      rc = idxProcessOneTrigger(p, pIter, pzErr);
    }
    pEnd = pFirst;
    pFirst = p->pWrite;
  }

  return rc;
}


static int idxCreateVtabSchema(sqlite3expert *p, char **pzErrmsg){
  int rc = idxRegisterVtab(p);
  sqlite3_stmt *pSchema = 0;

  /* For each table in the main db schema:
  **
  **   1) Add an entry to the p->pTable list, and
  **   2) Create the equivalent virtual table in dbv.
  */
  rc = idxPrepareStmt(p->db, &pSchema, pzErrmsg,
      "SELECT type, name, sql, 1 FROM sqlite_master "
      "WHERE type IN ('table','view') AND name NOT LIKE 'sqlite_%%' "
      " UNION ALL "
      "SELECT type, name, sql, 2 FROM sqlite_master "
      "WHERE type = 'trigger'"
      "  AND tbl_name IN(SELECT name FROM sqlite_master WHERE type = 'view') "
      "ORDER BY 4, 1"
  );
  while( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pSchema) ){
    const char *zType = (const char*)sqlite3_column_text(pSchema, 0);
    const char *zName = (const char*)sqlite3_column_text(pSchema, 1);
    const char *zSql = (const char*)sqlite3_column_text(pSchema, 2);

    if( zType[0]=='v' || zType[1]=='r' ){
      rc = sqlite3_exec(p->dbv, zSql, 0, 0, pzErrmsg);
    }else{
      IdxTable *pTab;
      rc = idxGetTableInfo(p->db, zName, &pTab, pzErrmsg);
      if( rc==SQLITE_OK ){
        int i;
        char *zInner = 0;
        char *zOuter = 0;
        pTab->pNext = p->pTable;
        p->pTable = pTab;

        /* The statement the vtab will pass to sqlite3_declare_vtab() */
        zInner = idxAppendText(&rc, 0, "CREATE TABLE x(");
        for(i=0; i<pTab->nCol; i++){
          zInner = idxAppendText(&rc, zInner, "%s%Q COLLATE %s", 
              (i==0 ? "" : ", "), pTab->aCol[i].zName, pTab->aCol[i].zColl
          );
        }
        zInner = idxAppendText(&rc, zInner, ")");

        /* The CVT statement to create the vtab */
        zOuter = idxAppendText(&rc, 0, 
            "CREATE VIRTUAL TABLE %Q USING expert(%Q)", zName, zInner
        );
        if( rc==SQLITE_OK ){
          rc = sqlite3_exec(p->dbv, zOuter, 0, 0, pzErrmsg);
        }
        sqlite3_free(zInner);
        sqlite3_free(zOuter);
      }
    }
  }
  idxFinalize(&rc, pSchema);
  return rc;
}

struct IdxSampleCtx {
  int iTarget;
  double target;                  /* Target nRet/nRow value */
  double nRow;                    /* Number of rows seen */
  double nRet;                    /* Number of rows returned */
};

static void idxSampleFunc(
  sqlite3_context *pCtx,
  int argc,
  sqlite3_value **argv
){
  struct IdxSampleCtx *p = (struct IdxSampleCtx*)sqlite3_user_data(pCtx);
  int bRet;

  (void)argv;
  assert( argc==0 );
  if( p->nRow==0.0 ){
    bRet = 1;
  }else{
    bRet = (p->nRet / p->nRow) <= p->target;
    if( bRet==0 ){
      unsigned short rnd;
      sqlite3_randomness(2, (void*)&rnd);
      bRet = ((int)rnd % 100) <= p->iTarget;
    }
  }

  sqlite3_result_int(pCtx, bRet);
  p->nRow += 1.0;
  p->nRet += (double)bRet;
}

struct IdxRemCtx {
  int nSlot;
  struct IdxRemSlot {
    int eType;                    /* SQLITE_NULL, INTEGER, REAL, TEXT, BLOB */
    i64 iVal;                     /* SQLITE_INTEGER value */
    double rVal;                  /* SQLITE_FLOAT value */
    int nByte;                    /* Bytes of space allocated at z */
    int n;                        /* Size of buffer z */
    char *z;                      /* SQLITE_TEXT/BLOB value */
  } aSlot[1];
};

/*
** Implementation of scalar function rem().
*/
static void idxRemFunc(
  sqlite3_context *pCtx,
  int argc,
  sqlite3_value **argv
){
  struct IdxRemCtx *p = (struct IdxRemCtx*)sqlite3_user_data(pCtx);
  struct IdxRemSlot *pSlot;
  int iSlot;
  assert( argc==2 );

  iSlot = sqlite3_value_int(argv[0]);
  assert( iSlot<=p->nSlot );
  pSlot = &p->aSlot[iSlot];

  switch( pSlot->eType ){
    case SQLITE_NULL:
      /* no-op */
      break;

    case SQLITE_INTEGER:
      sqlite3_result_int64(pCtx, pSlot->iVal);
      break;

    case SQLITE_FLOAT:
      sqlite3_result_double(pCtx, pSlot->rVal);
      break;

    case SQLITE_BLOB:
      sqlite3_result_blob(pCtx, pSlot->z, pSlot->n, SQLITE_TRANSIENT);
      break;

    case SQLITE_TEXT:
      sqlite3_result_text(pCtx, pSlot->z, pSlot->n, SQLITE_TRANSIENT);
      break;
  }

  pSlot->eType = sqlite3_value_type(argv[1]);
  switch( pSlot->eType ){
    case SQLITE_NULL:
      /* no-op */
      break;

    case SQLITE_INTEGER:
      pSlot->iVal = sqlite3_value_int64(argv[1]);
      break;

    case SQLITE_FLOAT:
      pSlot->rVal = sqlite3_value_double(argv[1]);
      break;

    case SQLITE_BLOB:
    case SQLITE_TEXT: {
      int nByte = sqlite3_value_bytes(argv[1]);
      if( nByte>pSlot->nByte ){
        char *zNew = (char*)sqlite3_realloc(pSlot->z, nByte*2);
        if( zNew==0 ){
          sqlite3_result_error_nomem(pCtx);
          return;
        }
        pSlot->nByte = nByte*2;
        pSlot->z = zNew;
      }
      pSlot->n = nByte;
      if( pSlot->eType==SQLITE_BLOB ){
        memcpy(pSlot->z, sqlite3_value_blob(argv[1]), nByte);
      }else{
        memcpy(pSlot->z, sqlite3_value_text(argv[1]), nByte);
      }
      break;
    }
  }
}

static int idxLargestIndex(sqlite3 *db, int *pnMax, char **pzErr){
  int rc = SQLITE_OK;
  const char *zMax = 
    "SELECT max(i.seqno) FROM "
    "  sqlite_master AS s, "
    "  pragma_index_list(s.name) AS l, "
    "  pragma_index_info(l.name) AS i "
    "WHERE s.type = 'table'";
  sqlite3_stmt *pMax = 0;

  *pnMax = 0;
  rc = idxPrepareStmt(db, &pMax, pzErr, zMax);
  if( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pMax) ){
    *pnMax = sqlite3_column_int(pMax, 0) + 1;
  }
  idxFinalize(&rc, pMax);

  return rc;
}

static int idxPopulateOneStat1(
  sqlite3expert *p,
  sqlite3_stmt *pIndexXInfo,
  sqlite3_stmt *pWriteStat,
  const char *zTab,
  const char *zIdx,
  char **pzErr
){
  char *zCols = 0;
  char *zOrder = 0;
  char *zQuery = 0;
  int nCol = 0;
  int i;
  sqlite3_stmt *pQuery = 0;
  int *aStat = 0;
  int rc = SQLITE_OK;

  assert( p->iSample>0 );

  /* Formulate the query text */
  sqlite3_bind_text(pIndexXInfo, 1, zIdx, -1, SQLITE_STATIC);
  while( SQLITE_OK==rc && SQLITE_ROW==sqlite3_step(pIndexXInfo) ){
    const char *zComma = zCols==0 ? "" : ", ";
    const char *zName = (const char*)sqlite3_column_text(pIndexXInfo, 0);
    const char *zColl = (const char*)sqlite3_column_text(pIndexXInfo, 1);
    zCols = idxAppendText(&rc, zCols, 
        "%sx.%Q IS rem(%d, x.%Q) COLLATE %s", zComma, zName, nCol, zName, zColl
    );
    zOrder = idxAppendText(&rc, zOrder, "%s%d", zComma, ++nCol);
  }
  sqlite3_reset(pIndexXInfo);
  if( rc==SQLITE_OK ){
    if( p->iSample==100 ){
      zQuery = sqlite3_mprintf(
          "SELECT %s FROM %Q x ORDER BY %s", zCols, zTab, zOrder
      );
    }else{
      zQuery = sqlite3_mprintf(
          "SELECT %s FROM temp."UNIQUE_TABLE_NAME" x ORDER BY %s", zCols, zOrder
      );
    }
  }
  sqlite3_free(zCols);
  sqlite3_free(zOrder);

  /* Formulate the query text */
  if( rc==SQLITE_OK ){
    sqlite3 *dbrem = (p->iSample==100 ? p->db : p->dbv);
    rc = idxPrepareStmt(dbrem, &pQuery, pzErr, zQuery);
  }
  sqlite3_free(zQuery);

  if( rc==SQLITE_OK ){
    aStat = (int*)idxMalloc(&rc, sizeof(int)*(nCol+1));
  }
  if( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pQuery) ){
    IdxHashEntry *pEntry;
    char *zStat = 0;
    for(i=0; i<=nCol; i++) aStat[i] = 1;
    while( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pQuery) ){
      aStat[0]++;
      for(i=0; i<nCol; i++){
        if( sqlite3_column_int(pQuery, i)==0 ) break;
      }
      for(/*no-op*/; i<nCol; i++){
        aStat[i+1]++;
      }
    }

    if( rc==SQLITE_OK ){
      int s0 = aStat[0];
      zStat = sqlite3_mprintf("%d", s0);
      if( zStat==0 ) rc = SQLITE_NOMEM;
      for(i=1; rc==SQLITE_OK && i<=nCol; i++){
        zStat = idxAppendText(&rc, zStat, " %d", (s0+aStat[i]/2) / aStat[i]);
      }
    }

    if( rc==SQLITE_OK ){
      sqlite3_bind_text(pWriteStat, 1, zTab, -1, SQLITE_STATIC);
      sqlite3_bind_text(pWriteStat, 2, zIdx, -1, SQLITE_STATIC);
      sqlite3_bind_text(pWriteStat, 3, zStat, -1, SQLITE_STATIC);
      sqlite3_step(pWriteStat);
      rc = sqlite3_reset(pWriteStat);
    }

    pEntry = idxHashFind(&p->hIdx, zIdx, STRLEN(zIdx));
    if( pEntry ){
      assert( pEntry->zVal2==0 );
      pEntry->zVal2 = zStat;
    }else{
      sqlite3_free(zStat);
    }
  }
  sqlite3_free(aStat);
  idxFinalize(&rc, pQuery);

  return rc;
}

static int idxBuildSampleTable(sqlite3expert *p, const char *zTab){
  int rc;
  char *zSql;

  rc = sqlite3_exec(p->dbv,"DROP TABLE IF EXISTS temp."UNIQUE_TABLE_NAME,0,0,0);
  if( rc!=SQLITE_OK ) return rc;

  zSql = sqlite3_mprintf(
      "CREATE TABLE temp." UNIQUE_TABLE_NAME " AS SELECT * FROM %Q", zTab
  );
  if( zSql==0 ) return SQLITE_NOMEM;
  rc = sqlite3_exec(p->dbv, zSql, 0, 0, 0);
  sqlite3_free(zSql);

  return rc;
}

/*
** This function is called as part of sqlite3_expert_analyze(). Candidate
** indexes have already been created in database sqlite3expert.dbm, this
** function populates sqlite_stat1 table in the same database.
**
** The stat1 data is generated by querying the 
*/
static int idxPopulateStat1(sqlite3expert *p, char **pzErr){
  int rc = SQLITE_OK;
  int nMax =0;
  struct IdxRemCtx *pCtx = 0;
  struct IdxSampleCtx samplectx; 
  int i;
  i64 iPrev = -100000;
  sqlite3_stmt *pAllIndex = 0;
  sqlite3_stmt *pIndexXInfo = 0;
  sqlite3_stmt *pWrite = 0;

  const char *zAllIndex =
    "SELECT s.rowid, s.name, l.name FROM "
    "  sqlite_master AS s, "
    "  pragma_index_list(s.name) AS l "
    "WHERE s.type = 'table'";
  const char *zIndexXInfo = 
    "SELECT name, coll FROM pragma_index_xinfo(?) WHERE key";
  const char *zWrite = "INSERT INTO sqlite_stat1 VALUES(?, ?, ?)";

  /* If iSample==0, no sqlite_stat1 data is required. */
  if( p->iSample==0 ) return SQLITE_OK;

  rc = idxLargestIndex(p->dbm, &nMax, pzErr);
  if( nMax<=0 || rc!=SQLITE_OK ) return rc;

  rc = sqlite3_exec(p->dbm, "ANALYZE; PRAGMA writable_schema=1", 0, 0, 0);

  if( rc==SQLITE_OK ){
    int nByte = sizeof(struct IdxRemCtx) + (sizeof(struct IdxRemSlot) * nMax);
    pCtx = (struct IdxRemCtx*)idxMalloc(&rc, nByte);
  }

  if( rc==SQLITE_OK ){
    sqlite3 *dbrem = (p->iSample==100 ? p->db : p->dbv);
    rc = sqlite3_create_function(
        dbrem, "rem", 2, SQLITE_UTF8, (void*)pCtx, idxRemFunc, 0, 0
    );
  }
  if( rc==SQLITE_OK ){
    rc = sqlite3_create_function(
        p->db, "sample", 0, SQLITE_UTF8, (void*)&samplectx, idxSampleFunc, 0, 0
    );
  }

  if( rc==SQLITE_OK ){
    pCtx->nSlot = nMax+1;
    rc = idxPrepareStmt(p->dbm, &pAllIndex, pzErr, zAllIndex);
  }
  if( rc==SQLITE_OK ){
    rc = idxPrepareStmt(p->dbm, &pIndexXInfo, pzErr, zIndexXInfo);
  }
  if( rc==SQLITE_OK ){
    rc = idxPrepareStmt(p->dbm, &pWrite, pzErr, zWrite);
  }

  while( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pAllIndex) ){
    i64 iRowid = sqlite3_column_int64(pAllIndex, 0);
    const char *zTab = (const char*)sqlite3_column_text(pAllIndex, 1);
    const char *zIdx = (const char*)sqlite3_column_text(pAllIndex, 2);
    if( p->iSample<100 && iPrev!=iRowid ){
      samplectx.target = (double)p->iSample / 100.0;
      samplectx.iTarget = p->iSample;
      samplectx.nRow = 0.0;
      samplectx.nRet = 0.0;
      rc = idxBuildSampleTable(p, zTab);
      if( rc!=SQLITE_OK ) break;
    }
    rc = idxPopulateOneStat1(p, pIndexXInfo, pWrite, zTab, zIdx, pzErr);
    iPrev = iRowid;
  }
  if( rc==SQLITE_OK && p->iSample<100 ){
    rc = sqlite3_exec(p->dbv, 
        "DROP TABLE IF EXISTS temp." UNIQUE_TABLE_NAME, 0,0,0
    );
  }

  idxFinalize(&rc, pAllIndex);
  idxFinalize(&rc, pIndexXInfo);
  idxFinalize(&rc, pWrite);

  for(i=0; i<pCtx->nSlot; i++){
    sqlite3_free(pCtx->aSlot[i].z);
  }
  sqlite3_free(pCtx);

  if( rc==SQLITE_OK ){
    rc = sqlite3_exec(p->dbm, "ANALYZE sqlite_master", 0, 0, 0);
  }

  sqlite3_exec(p->db, "DROP TABLE IF EXISTS temp."UNIQUE_TABLE_NAME,0,0,0);
  return rc;
}

/*
** Allocate a new sqlite3expert object.
*/
sqlite3expert *sqlite3_expert_new(sqlite3 *db, char **pzErrmsg){
  int rc = SQLITE_OK;
  sqlite3expert *pNew;

  pNew = (sqlite3expert*)idxMalloc(&rc, sizeof(sqlite3expert));

  /* Open two in-memory databases to work with. The "vtab database" (dbv)
  ** will contain a virtual table corresponding to each real table in
  ** the user database schema, and a copy of each view. It is used to
  ** collect information regarding the WHERE, ORDER BY and other clauses
  ** of the user's query.
  */
  if( rc==SQLITE_OK ){
    pNew->db = db;
    pNew->iSample = 100;
    rc = sqlite3_open(":memory:", &pNew->dbv);
  }
  if( rc==SQLITE_OK ){
    rc = sqlite3_open(":memory:", &pNew->dbm);
    if( rc==SQLITE_OK ){
      sqlite3_db_config(pNew->dbm, SQLITE_DBCONFIG_TRIGGER_EQP, 1, (int*)0);
    }
  }
  

  /* Copy the entire schema of database [db] into [dbm]. */
  if( rc==SQLITE_OK ){
    sqlite3_stmt *pSql;
    rc = idxPrintfPrepareStmt(pNew->db, &pSql, pzErrmsg, 
        "SELECT sql FROM sqlite_master WHERE name NOT LIKE 'sqlite_%%'"
        " AND sql NOT LIKE 'CREATE VIRTUAL %%'"
    );
    while( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pSql) ){
      const char *zSql = (const char*)sqlite3_column_text(pSql, 0);
      rc = sqlite3_exec(pNew->dbm, zSql, 0, 0, pzErrmsg);
    }
    idxFinalize(&rc, pSql);
  }

  /* Create the vtab schema */
  if( rc==SQLITE_OK ){
    rc = idxCreateVtabSchema(pNew, pzErrmsg);
  }

  /* Register the auth callback with dbv */
  if( rc==SQLITE_OK ){
    sqlite3_set_authorizer(pNew->dbv, idxAuthCallback, (void*)pNew);
  }

  /* If an error has occurred, free the new object and reutrn NULL. Otherwise,
  ** return the new sqlite3expert handle.  */
  if( rc!=SQLITE_OK ){
    sqlite3_expert_destroy(pNew);
    pNew = 0;
  }
  return pNew;
}

/*
** Configure an sqlite3expert object.
*/
int sqlite3_expert_config(sqlite3expert *p, int op, ...){
  int rc = SQLITE_OK;
  va_list ap;
  va_start(ap, op);
  switch( op ){
    case EXPERT_CONFIG_SAMPLE: {
      int iVal = va_arg(ap, int);
      if( iVal<0 ) iVal = 0;
      if( iVal>100 ) iVal = 100;
      p->iSample = iVal;
      break;
    }
    default:
      rc = SQLITE_NOTFOUND;
      break;
  }

  va_end(ap);
  return rc;
}

/*
** Add an SQL statement to the analysis.
*/
int sqlite3_expert_sql(
  sqlite3expert *p,               /* From sqlite3_expert_new() */
  const char *zSql,               /* SQL statement to add */
  char **pzErr                    /* OUT: Error message (if any) */
){
  IdxScan *pScanOrig = p->pScan;
  IdxStatement *pStmtOrig = p->pStatement;
  int rc = SQLITE_OK;
  const char *zStmt = zSql;

  if( p->bRun ) return SQLITE_MISUSE;

  while( rc==SQLITE_OK && zStmt && zStmt[0] ){
    sqlite3_stmt *pStmt = 0;
    rc = sqlite3_prepare_v2(p->dbv, zStmt, -1, &pStmt, &zStmt);
    if( rc==SQLITE_OK ){
      if( pStmt ){
        IdxStatement *pNew;
        const char *z = sqlite3_sql(pStmt);
        int n = STRLEN(z);
        pNew = (IdxStatement*)idxMalloc(&rc, sizeof(IdxStatement) + n+1);
        if( rc==SQLITE_OK ){
          pNew->zSql = (char*)&pNew[1];
          memcpy(pNew->zSql, z, n+1);
          pNew->pNext = p->pStatement;
          if( p->pStatement ) pNew->iId = p->pStatement->iId+1;
          p->pStatement = pNew;
        }
        sqlite3_finalize(pStmt);
      }
    }else{
      idxDatabaseError(p->dbv, pzErr);
    }
  }

  if( rc!=SQLITE_OK ){
    idxScanFree(p->pScan, pScanOrig);
    idxStatementFree(p->pStatement, pStmtOrig);
    p->pScan = pScanOrig;
    p->pStatement = pStmtOrig;
  }

  return rc;
}

int sqlite3_expert_analyze(sqlite3expert *p, char **pzErr){
  int rc;
  IdxHashEntry *pEntry;

  /* Do trigger processing to collect any extra IdxScan structures */
  rc = idxProcessTriggers(p, pzErr);

  /* Create candidate indexes within the in-memory database file */
  if( rc==SQLITE_OK ){
    rc = idxCreateCandidates(p);
  }

  /* Generate the stat1 data */
  if( rc==SQLITE_OK ){
    rc = idxPopulateStat1(p, pzErr);
  }

  /* Formulate the EXPERT_REPORT_CANDIDATES text */
  for(pEntry=p->hIdx.pFirst; pEntry; pEntry=pEntry->pNext){
    p->zCandidates = idxAppendText(&rc, p->zCandidates, 
        "%s;%s%s\n", pEntry->zVal, 
        pEntry->zVal2 ? " -- stat1: " : "", pEntry->zVal2
    );
  }

  /* Figure out which of the candidate indexes are preferred by the query
  ** planner and report the results to the user.  */
  if( rc==SQLITE_OK ){
    rc = idxFindIndexes(p, pzErr);
  }

  if( rc==SQLITE_OK ){
    p->bRun = 1;
  }
  return rc;
}

/*
** Return the total number of statements that have been added to this
** sqlite3expert using sqlite3_expert_sql().
*/
int sqlite3_expert_count(sqlite3expert *p){
  int nRet = 0;
  if( p->pStatement ) nRet = p->pStatement->iId+1;
  return nRet;
}

/*
** Return a component of the report.
*/
const char *sqlite3_expert_report(sqlite3expert *p, int iStmt, int eReport){
  const char *zRet = 0;
  IdxStatement *pStmt;

  if( p->bRun==0 ) return 0;
  for(pStmt=p->pStatement; pStmt && pStmt->iId!=iStmt; pStmt=pStmt->pNext);
  switch( eReport ){
    case EXPERT_REPORT_SQL:
      if( pStmt ) zRet = pStmt->zSql;
      break;
    case EXPERT_REPORT_INDEXES:
      if( pStmt ) zRet = pStmt->zIdx;
      break;
    case EXPERT_REPORT_PLAN:
      if( pStmt ) zRet = pStmt->zEQP;
      break;
    case EXPERT_REPORT_CANDIDATES:
      zRet = p->zCandidates;
      break;
  }
  return zRet;
}

/*
** Free an sqlite3expert object.
*/
void sqlite3_expert_destroy(sqlite3expert *p){
  if( p ){
    sqlite3_close(p->dbm);
    sqlite3_close(p->dbv);
    idxScanFree(p->pScan, 0);
    idxStatementFree(p->pStatement, 0);
    idxTableFree(p->pTable);
    idxWriteFree(p->pWrite);
    idxHashClear(&p->hIdx);
    sqlite3_free(p->zCandidates);
    sqlite3_free(p);
  }
}

#endif /* ifndef SQLITE_OMIT_VIRTUAL_TABLE */

/*
** 2017 April 07
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
*/


#include "sqlite3.h"

typedef struct sqlite3expert sqlite3expert;

/*
** Create a new sqlite3expert object.
**
** If successful, a pointer to the new object is returned and (*pzErr) set
** to NULL. Or, if an error occurs, NULL is returned and (*pzErr) set to
** an English-language error message. In this case it is the responsibility
** of the caller to eventually free the error message buffer using
** sqlite3_free().
*/
sqlite3expert *sqlite3_expert_new(sqlite3 *db, char **pzErr);

/*
** Configure an sqlite3expert object.
**
** EXPERT_CONFIG_SAMPLE:
**   By default, sqlite3_expert_analyze() generates sqlite_stat1 data for
**   each candidate index. This involves scanning and sorting the entire
**   contents of each user database table once for each candidate index
**   associated with the table. For large databases, this can be 
**   prohibitively slow. This option allows the sqlite3expert object to
**   be configured so that sqlite_stat1 data is instead generated based on a
**   subset of each table, or so that no sqlite_stat1 data is used at all.
**
**   A single integer argument is passed to this option. If the value is less
**   than or equal to zero, then no sqlite_stat1 data is generated or used by
**   the analysis - indexes are recommended based on the database schema only.
**   Or, if the value is 100 or greater, complete sqlite_stat1 data is
**   generated for each candidate index (this is the default). Finally, if the
**   value falls between 0 and 100, then it represents the percentage of user
**   table rows that should be considered when generating sqlite_stat1 data.
**
**   Examples:
**
**     // Do not generate any sqlite_stat1 data
**     sqlite3_expert_config(pExpert, EXPERT_CONFIG_SAMPLE, 0);
**
**     // Generate sqlite_stat1 data based on 10% of the rows in each table.
**     sqlite3_expert_config(pExpert, EXPERT_CONFIG_SAMPLE, 10);
*/
int sqlite3_expert_config(sqlite3expert *p, int op, ...);

#define EXPERT_CONFIG_SAMPLE 1    /* int */

/*
** Specify zero or more SQL statements to be included in the analysis.
**
** Buffer zSql must contain zero or more complete SQL statements. This
** function parses all statements contained in the buffer and adds them
** to the internal list of statements to analyze. If successful, SQLITE_OK
** is returned and (*pzErr) set to NULL. Or, if an error occurs - for example
** due to a error in the SQL - an SQLite error code is returned and (*pzErr)
** may be set to point to an English language error message. In this case
** the caller is responsible for eventually freeing the error message buffer
** using sqlite3_free().
**
** If an error does occur while processing one of the statements in the
** buffer passed as the second argument, none of the statements in the
** buffer are added to the analysis.
**
** This function must be called before sqlite3_expert_analyze(). If a call
** to this function is made on an sqlite3expert object that has already
** been passed to sqlite3_expert_analyze() SQLITE_MISUSE is returned
** immediately and no statements are added to the analysis.
*/
int sqlite3_expert_sql(
  sqlite3expert *p,               /* From a successful sqlite3_expert_new() */
  const char *zSql,               /* SQL statement(s) to add */
  char **pzErr                    /* OUT: Error message (if any) */
);


/*
** This function is called after the sqlite3expert object has been configured
** with all SQL statements using sqlite3_expert_sql() to actually perform
** the analysis. Once this function has been called, it is not possible to
** add further SQL statements to the analysis.
**
** If successful, SQLITE_OK is returned and (*pzErr) is set to NULL. Or, if
** an error occurs, an SQLite error code is returned and (*pzErr) set to 
** point to a buffer containing an English language error message. In this
** case it is the responsibility of the caller to eventually free the buffer
** using sqlite3_free().
**
** If an error does occur within this function, the sqlite3expert object
** is no longer useful for any purpose. At that point it is no longer
** possible to add further SQL statements to the object or to re-attempt
** the analysis. The sqlite3expert object must still be freed using a call
** sqlite3_expert_destroy().
*/
int sqlite3_expert_analyze(sqlite3expert *p, char **pzErr);

/*
** Return the total number of statements loaded using sqlite3_expert_sql().
** The total number of SQL statements may be different from the total number
** to calls to sqlite3_expert_sql().
*/
int sqlite3_expert_count(sqlite3expert*);

/*
** Return a component of the report.
**
** This function is called after sqlite3_expert_analyze() to extract the
** results of the analysis. Each call to this function returns either a
** NULL pointer or a pointer to a buffer containing a nul-terminated string.
** The value passed as the third argument must be one of the EXPERT_REPORT_*
** #define constants defined below.
**
** For some EXPERT_REPORT_* parameters, the buffer returned contains 
** information relating to a specific SQL statement. In these cases that
** SQL statement is identified by the value passed as the second argument.
** SQL statements are numbered from 0 in the order in which they are parsed.
** If an out-of-range value (less than zero or equal to or greater than the
** value returned by sqlite3_expert_count()) is passed as the second argument
** along with such an EXPERT_REPORT_* parameter, NULL is always returned.
**
** EXPERT_REPORT_SQL:
**   Return the text of SQL statement iStmt.
**
** EXPERT_REPORT_INDEXES:
**   Return a buffer containing the CREATE INDEX statements for all recommended
**   indexes for statement iStmt. If there are no new recommeded indexes, NULL 
**   is returned.
**
** EXPERT_REPORT_PLAN:
**   Return a buffer containing the EXPLAIN QUERY PLAN output for SQL query
**   iStmt after the proposed indexes have been added to the database schema.
**
** EXPERT_REPORT_CANDIDATES:
**   Return a pointer to a buffer containing the CREATE INDEX statements 
**   for all indexes that were tested (for all SQL statements). The iStmt
**   parameter is ignored for EXPERT_REPORT_CANDIDATES calls.
*/
const char *sqlite3_expert_report(sqlite3expert*, int iStmt, int eReport);

/*
** Values for the third argument passed to sqlite3_expert_report().
*/
#define EXPERT_REPORT_SQL        1
#define EXPERT_REPORT_INDEXES    2
#define EXPERT_REPORT_PLAN       3
#define EXPERT_REPORT_CANDIDATES 4

/*
** Free an (sqlite3expert*) handle and all associated resources. There 
** should be one call to this function for each successful call to 
** sqlite3-expert_new().
*/
void sqlite3_expert_destroy(sqlite3expert*);

/*
** 2017 April 07
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
*/

#if defined(SQLITE_TEST)

#include "sqlite3expert.h"
#include <assert.h>
#include <string.h>

#if defined(INCLUDE_SQLITE_TCL_H)
#  include "sqlite_tcl.h"
#else
#  include "tcl.h"
#  ifndef SQLITE_TCLAPI
#    define SQLITE_TCLAPI
#  endif
#endif

#ifndef SQLITE_OMIT_VIRTUALTABLE

/*
** Extract an sqlite3* db handle from the object passed as the second
** argument. If successful, set *pDb to point to the db handle and return
** TCL_OK. Otherwise, return TCL_ERROR.
*/
static int dbHandleFromObj(Tcl_Interp *interp, Tcl_Obj *pObj, sqlite3 **pDb){
  Tcl_CmdInfo info;
  if( 0==Tcl_GetCommandInfo(interp, Tcl_GetString(pObj), &info) ){
    Tcl_AppendResult(interp, "no such handle: ", Tcl_GetString(pObj), 0);
    return TCL_ERROR;
  }

  *pDb = *(sqlite3 **)info.objClientData;
  return TCL_OK;
}


/*
** Tclcmd:  $expert sql SQL
**          $expert analyze
**          $expert count
**          $expert report STMT EREPORT
**          $expert destroy
*/
static int SQLITE_TCLAPI testExpertCmd(
  void *clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  sqlite3expert *pExpert = (sqlite3expert*)clientData;
  struct Subcmd {
    const char *zSub;
    int nArg;
    const char *zMsg;
  } aSub[] = {
    { "sql",       1, "TABLE",        }, /* 0 */
    { "analyze",   0, "",             }, /* 1 */
    { "count",     0, "",             }, /* 2 */
    { "report",    2, "STMT EREPORT", }, /* 3 */
    { "destroy",   0, "",             }, /* 4 */
    { 0 }
  };
  int iSub;
  int rc = TCL_OK;
  char *zErr = 0;

  if( objc<2 ){
    Tcl_WrongNumArgs(interp, 1, objv, "SUBCOMMAND ...");
    return TCL_ERROR;
  }
  rc = Tcl_GetIndexFromObjStruct(interp, 
      objv[1], aSub, sizeof(aSub[0]), "sub-command", 0, &iSub
  );
  if( rc!=TCL_OK ) return rc;
  if( objc!=2+aSub[iSub].nArg ){
    Tcl_WrongNumArgs(interp, 2, objv, aSub[iSub].zMsg);
    return TCL_ERROR;
  }

  switch( iSub ){
    case 0: {      /* sql */
      char *zArg = Tcl_GetString(objv[2]);
      rc = sqlite3_expert_sql(pExpert, zArg, &zErr);
      break;
    }

    case 1: {      /* analyze */
      rc = sqlite3_expert_analyze(pExpert, &zErr);
      break;
    }

    case 2: {      /* count */
      int n = sqlite3_expert_count(pExpert);
      Tcl_SetObjResult(interp, Tcl_NewIntObj(n));
      break;
    }

    case 3: {      /* report */
      const char *aEnum[] = {
        "sql", "indexes", "plan", "candidates", 0
      };
      int iEnum;
      int iStmt;
      const char *zReport;

      if( Tcl_GetIntFromObj(interp, objv[2], &iStmt) 
       || Tcl_GetIndexFromObj(interp, objv[3], aEnum, "report", 0, &iEnum)
      ){
        return TCL_ERROR;
      }

      assert( EXPERT_REPORT_SQL==1 );
      assert( EXPERT_REPORT_INDEXES==2 );
      assert( EXPERT_REPORT_PLAN==3 );
      assert( EXPERT_REPORT_CANDIDATES==4 );
      zReport = sqlite3_expert_report(pExpert, iStmt, 1+iEnum);
      Tcl_SetObjResult(interp, Tcl_NewStringObj(zReport, -1));
      break;
    }

    default:       /* destroy */
      assert( iSub==4 );     
      Tcl_DeleteCommand(interp, Tcl_GetString(objv[0]));
      break;
  }

  if( rc!=TCL_OK ){
    if( zErr ){
      Tcl_SetObjResult(interp, Tcl_NewStringObj(zErr, -1));
    }else{
      extern const char *sqlite3ErrName(int);
      Tcl_SetObjResult(interp, Tcl_NewStringObj(sqlite3ErrName(rc), -1));
    }
  }
  sqlite3_free(zErr);
  return rc;
}

static void SQLITE_TCLAPI testExpertDel(void *clientData){
  sqlite3expert *pExpert = (sqlite3expert*)clientData;
  sqlite3_expert_destroy(pExpert);
}

/*
** sqlite3_expert_new DB
*/
static int SQLITE_TCLAPI test_sqlite3_expert_new(
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  static int iCmd = 0;
  sqlite3 *db;
  char *zCmd = 0;
  char *zErr = 0;
  sqlite3expert *pExpert;
  int rc = TCL_OK;

  if( objc!=2 ){
    Tcl_WrongNumArgs(interp, 1, objv, "DB");
    return TCL_ERROR;
  }
  if( dbHandleFromObj(interp, objv[1], &db) ){
    return TCL_ERROR;
  }

  zCmd = sqlite3_mprintf("sqlite3expert%d", ++iCmd);
  if( zCmd==0 ){
    Tcl_AppendResult(interp, "out of memory", (char*)0);
    return TCL_ERROR;
  }

  pExpert = sqlite3_expert_new(db, &zErr);
  if( pExpert==0 ){
    Tcl_AppendResult(interp, zErr, (char*)0);
    rc = TCL_ERROR;
  }else{
    void *p = (void*)pExpert;
    Tcl_CreateObjCommand(interp, zCmd, testExpertCmd, p, testExpertDel);
    Tcl_SetObjResult(interp, Tcl_NewStringObj(zCmd, -1));
  }

  sqlite3_free(zCmd);
  sqlite3_free(zErr);
  return rc;
}

#endif  /* ifndef SQLITE_OMIT_VIRTUALTABLE */

int TestExpert_Init(Tcl_Interp *interp){
#ifndef SQLITE_OMIT_VIRTUALTABLE
  struct Cmd {
    const char *zCmd;
    Tcl_ObjCmdProc *xProc;
  } aCmd[] = {
    { "sqlite3_expert_new", test_sqlite3_expert_new },
  };
  int i;

  for(i=0; i<sizeof(aCmd)/sizeof(struct Cmd); i++){
    struct Cmd *p = &aCmd[i];
    Tcl_CreateObjCommand(interp, p->zCmd, p->xProc, 0, 0);
  }
#endif
  return TCL_OK;
}

#endif

      sqlite3_reset(pCsr->pStmt);
      pCsr->pStmt = 0;
    }
    pCsr->bSeekStmt = 0;
  }
  sqlite3_finalize(pCsr->pStmt);
}

/*
** Free all resources currently held by the cursor passed as the only
** argument.
*/
static void fts3ClearCursor(Fts3Cursor *pCsr){
  fts3CursorFinalizeStmt(pCsr);
  sqlite3Fts3FreeDeferredTokens(pCsr);
  sqlite3_free(pCsr->aDoclist);
  sqlite3Fts3MIBufferFree(pCsr->pMIBuffer);
  sqlite3Fts3ExprFree(pCsr->pExpr);
  memset(&(&pCsr->base)[1], 0, sizeof(Fts3Cursor)-sizeof(sqlite3_vtab_cursor));
}

/*
** Close the cursor.  For additional information see the documentation
** on the xClose method of the virtual table interface.
*/
static int fts3CloseMethod(sqlite3_vtab_cursor *pCursor){
  Fts3Cursor *pCsr = (Fts3Cursor *)pCursor;
  assert( ((Fts3Table *)pCsr->base.pVtab)->pSegments==0 );
  fts3ClearCursor(pCsr);




  assert( ((Fts3Table *)pCsr->base.pVtab)->pSegments==0 );
  sqlite3_free(pCsr);
  return SQLITE_OK;
}

/*
** If pCsr->pStmt has not been prepared (i.e. if pCsr->pStmt==0), then

    char *zSql;
    if( p->pSeekStmt ){
      pCsr->pStmt = p->pSeekStmt;
      p->pSeekStmt = 0;
    }else{
      zSql = sqlite3_mprintf("SELECT %s WHERE rowid = ?", p->zReadExprlist);
      if( !zSql ) return SQLITE_NOMEM;
      rc = sqlite3_prepare_v3(p->db, zSql,-1,SQLITE_PREPARE_PERSISTENT,&pCsr->pStmt,0);
      sqlite3_free(zSql);
    }
    if( rc==SQLITE_OK ) pCsr->bSeekStmt = 1;
  }
  return rc;
}

  if( eSearch!=FTS3_FULLSCAN_SEARCH ) pCons = apVal[iIdx++];
  if( idxNum & FTS3_HAVE_LANGID ) pLangid = apVal[iIdx++];
  if( idxNum & FTS3_HAVE_DOCID_GE ) pDocidGe = apVal[iIdx++];
  if( idxNum & FTS3_HAVE_DOCID_LE ) pDocidLe = apVal[iIdx++];
  assert( iIdx==nVal );

  /* In case the cursor has been used before, clear it now. */
  fts3ClearCursor(pCsr);





  /* Set the lower and upper bounds on docids to return */
  pCsr->iMinDocid = fts3DocidRange(pDocidGe, SMALLEST_INT64);
  pCsr->iMaxDocid = fts3DocidRange(pDocidLe, LARGEST_INT64);

  if( idxStr ){
    pCsr->bDesc = (idxStr[0]=='D');

      );
    }else{
      zSql = sqlite3_mprintf("SELECT %s ORDER BY rowid %s", 
          p->zReadExprlist, (pCsr->bDesc ? "DESC" : "ASC")
      );
    }
    if( zSql ){
      rc = sqlite3_prepare_v3(p->db,zSql,-1,SQLITE_PREPARE_PERSISTENT,&pCsr->pStmt,0);
      sqlite3_free(zSql);
    }else{
      rc = SQLITE_NOMEM;
    }
  }else if( eSearch==FTS3_DOCID_SEARCH ){
    rc = fts3CursorSeekStmt(pCsr);
    if( rc==SQLITE_OK ){
      rc = sqlite3_bind_value(pCsr->pStmt, 1, pCons);
    }
  }
  if( rc!=SQLITE_OK ) return rc;

  return fts3NextMethod(pCursor);
}

/* 
** This is the xEof method of the virtual table. SQLite calls this 
** routine to find out if it has reached the end of a result set.
*/
static int fts3EofMethod(sqlite3_vtab_cursor *pCursor){
  Fts3Cursor *pCsr = (Fts3Cursor*)pCursor;
  if( pCsr->isEof ){
    fts3ClearCursor(pCsr);
    pCsr->isEof = 1;
  }
  return pCsr->isEof;
}

/* 
** This is the xRowid method. The SQLite core calls this routine to
** retrieve the rowid for the current row of the result set. fts3
** exposes %_content.docid as the rowid for the virtual table. The
** rowid should be written to *pRowid.

  /* The column value supplied by SQLite must be in range. */
  assert( iCol>=0 && iCol<=p->nColumn+2 );

  switch( iCol-p->nColumn ){
    case 0:
      /* The special 'table-name' column */

      sqlite3_result_pointer(pCtx, pCsr, "fts3cursor", 0);
      break;

    case 1:
      /* The docid column */
      sqlite3_result_int64(pCtx, pCsr->iPrevId);
      break;

*/
static int fts3FunctionArg(
  sqlite3_context *pContext,      /* SQL function call context */
  const char *zFunc,              /* Function name */
  sqlite3_value *pVal,            /* argv[0] passed to function */
  Fts3Cursor **ppCsr              /* OUT: Store cursor handle here */
){
  int rc;
  *ppCsr = (Fts3Cursor*)sqlite3_value_pointer(pVal, "fts3cursor");
  if( (*ppCsr)!=0 ){
    rc = SQLITE_OK;
  }else{
    char *zErr = sqlite3_mprintf("illegal first argument to %s", zFunc);
    sqlite3_result_error(pContext, zErr, -1);
    sqlite3_free(zErr);
    rc = SQLITE_ERROR;
  }
  return rc;

      zSql = sqlite3_mprintf(azSql[eStmt], p->zReadExprlist);
    }else{
      zSql = sqlite3_mprintf(azSql[eStmt], p->zDb, p->zName);
    }
    if( !zSql ){
      rc = SQLITE_NOMEM;
    }else{
      rc = sqlite3_prepare_v3(p->db, zSql, -1, SQLITE_PREPARE_PERSISTENT,
                              &pStmt, NULL);
      sqlite3_free(zSql);
      assert( rc==SQLITE_OK || pStmt==0 );
      p->aStmt[eStmt] = pStmt;
    }
  }
  if( apVal ){
    int i;

  sqlite3_stmt *pStmt;
  int rc = fts3SqlStmt(p, SQL_INSERT_SEGMENTS, &pStmt, 0);
  if( rc==SQLITE_OK ){
    sqlite3_bind_int64(pStmt, 1, iBlock);
    sqlite3_bind_blob(pStmt, 2, z, n, SQLITE_STATIC);
    sqlite3_step(pStmt);
    rc = sqlite3_reset(pStmt);
    sqlite3_bind_null(pStmt, 2);
  }
  return rc;
}

/*
** Find the largest relative level number in the table. If successful, set
** *pnMax to this value and return SQLITE_OK. Otherwise, if an error occurs,

      char *zEnd = sqlite3_mprintf("%lld %lld", iEndBlock, nLeafData);
      if( !zEnd ) return SQLITE_NOMEM;
      sqlite3_bind_text(pStmt, 5, zEnd, -1, sqlite3_free);
    }
    sqlite3_bind_blob(pStmt, 6, zRoot, nRoot, SQLITE_STATIC);
    sqlite3_step(pStmt);
    rc = sqlite3_reset(pStmt);
    sqlite3_bind_null(pStmt, 6);
  }
  return rc;
}

/*
** Return the size of the common prefix (if any) shared by zPrev and
** zNext, in bytes. For example, 

    *pRC = rc;
    return;
  }
  sqlite3_bind_int(pStmt, 1, FTS_STAT_DOCTOTAL);
  sqlite3_bind_blob(pStmt, 2, pBlob, nBlob, SQLITE_STATIC);
  sqlite3_step(pStmt);
  *pRC = sqlite3_reset(pStmt);
  sqlite3_bind_null(pStmt, 2);
  sqlite3_free(a);
}

/*
** Merge the entire database so that there is one segment for each 
** iIndex/iLangid combination.
*/

    if( rc==SQLITE_OK ){
      sqlite3_bind_int64(pChomp, 1, iNewStart);
      sqlite3_bind_blob(pChomp, 2, root.a, root.n, SQLITE_STATIC);
      sqlite3_bind_int64(pChomp, 3, iAbsLevel);
      sqlite3_bind_int(pChomp, 4, iIdx);
      sqlite3_step(pChomp);
      rc = sqlite3_reset(pChomp);
      sqlite3_bind_null(pChomp, 2);
    }
  }

  sqlite3_free(root.a);
  sqlite3_free(block.a);
  return rc;
}

  rc = fts3SqlStmt(p, SQL_REPLACE_STAT, &pReplace, 0);
  if( rc==SQLITE_OK ){
    sqlite3_bind_int(pReplace, 1, FTS_STAT_INCRMERGEHINT);
    sqlite3_bind_blob(pReplace, 2, pHint->a, pHint->n, SQLITE_STATIC);
    sqlite3_step(pReplace);
    rc = sqlite3_reset(pReplace);
    sqlite3_bind_null(pReplace, 2);
  }

  return rc;
}

/*
** Load an incr-merge hint from the database. The incr-merge hint, if one 

  sqlite3_vtab *pVtab,            /* FTS3 vtab object */
  int nArg,                       /* Size of argument array */
  sqlite3_value **apVal,          /* Array of arguments */
  sqlite_int64 *pRowid            /* OUT: The affected (or effected) rowid */
){
  Fts3Table *p = (Fts3Table *)pVtab;
  int rc = SQLITE_OK;             /* Return Code */

  u32 *aSzIns = 0;                /* Sizes of inserted documents */
  u32 *aSzDel = 0;                /* Sizes of deleted documents */
  int nChng = 0;                  /* Net change in number of documents */
  int bInsertDone = 0;

  /* At this point it must be known if the %_stat table exists or not.
  ** So bHasStat may not be 2.  */

    goto update_out;
  }

  /* If this is a DELETE or UPDATE operation, remove the old record. */
  if( sqlite3_value_type(apVal[0])!=SQLITE_NULL ){
    assert( sqlite3_value_type(apVal[0])==SQLITE_INTEGER );
    rc = fts3DeleteByRowid(p, apVal[0], &nChng, aSzDel);

  }
  
  /* If this is an INSERT or UPDATE operation, insert the new record. */
  if( nArg>1 && rc==SQLITE_OK ){
    int iLangid = sqlite3_value_int(apVal[2 + p->nColumn + 2]);
    if( bInsertDone==0 ){
      rc = fts3InsertData(p, apVal, pRowid);
      if( rc==SQLITE_CONSTRAINT && p->zContentTbl==0 ){
        rc = FTS_CORRUPT_VTAB;
      }
    }
    if( rc==SQLITE_OK ){
      rc = fts3PendingTermsDocid(p, 0, iLangid, *pRowid);
    }
    if( rc==SQLITE_OK ){
      assert( p->iPrevDocid==*pRowid );
      rc = fts3InsertTerms(p, iLangid, apVal, aSzIns);
    }
    if( p->bHasDocsize ){

Fts5ExprPhrase *sqlite3Fts5ParseTerm(
  Fts5Parse *pParse, 
  Fts5ExprPhrase *pPhrase, 
  Fts5Token *pToken,
  int bPrefix
);

void sqlite3Fts5ParseSetCaret(Fts5ExprPhrase*);

Fts5ExprNearset *sqlite3Fts5ParseNearset(
  Fts5Parse*, 
  Fts5ExprNearset*,
  Fts5ExprPhrase* 
);

    if( (iAdj+nToken)>nDocsize ) iAdj = nDocsize - nToken;
    if( iAdj<0 ) iAdj = 0;
    *piPos = iAdj;
  }

  return rc;
}

/*
** Return the value in pVal interpreted as utf-8 text. Except, if pVal 
** contains a NULL value, return a pointer to a static string zero
** bytes in length instead of a NULL pointer.
*/
static const char *fts5ValueToText(sqlite3_value *pVal){
  const char *zRet = (const char*)sqlite3_value_text(pVal);
  return zRet ? zRet : "";
}

/*
** Implementation of snippet() function.
*/
static void fts5SnippetFunction(
  const Fts5ExtensionApi *pApi,   /* API offered by current FTS version */
  Fts5Context *pFts,              /* First arg to pass to pApi functions */

    sqlite3_result_error(pCtx, zErr, -1);
    return;
  }

  nCol = pApi->xColumnCount(pFts);
  memset(&ctx, 0, sizeof(HighlightContext));
  iCol = sqlite3_value_int(apVal[0]);
  ctx.zOpen = fts5ValueToText(apVal[1]);
  ctx.zClose = fts5ValueToText(apVal[2]);
  zEllips = fts5ValueToText(apVal[3]);
  nToken = sqlite3_value_int(apVal[4]);

  iBestCol = (iCol>=0 ? iCol : 0);
  nPhrase = pApi->xPhraseCount(pFts);
  aSeen = sqlite3_malloc(nPhrase);
  if( aSeen==0 ){
    rc = SQLITE_NOMEM;