SQLite

#
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 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 \
         func.lo global.lo hash.lo \
         icu.lo insert.lo journal.lo legacy.lo loadext.lo \
         main.lo malloc.lo mem0.lo mem1.lo mem2.lo mem3.lo mem5.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 \

  $(TOP)/ext/fts3/fts3_hash.h \
  $(TOP)/ext/fts3/fts3_icu.c \
  $(TOP)/ext/fts3/fts3_porter.c \
  $(TOP)/ext/fts3/fts3_snippet.c \
  $(TOP)/ext/fts3/fts3_tokenizer.h \
  $(TOP)/ext/fts3/fts3_tokenizer.c \
  $(TOP)/ext/fts3/fts3_tokenizer1.c \
  $(TOP)/ext/fts3/fts3_tokenize_vtab.c \
  $(TOP)/ext/fts3/fts3_unicode.c \
  $(TOP)/ext/fts3/fts3_unicode2.c \
  $(TOP)/ext/fts3/fts3_write.c
SRC += \
  $(TOP)/ext/icu/sqliteicu.h \
  $(TOP)/ext/icu/icu.c
SRC += \

  $(TOP)/src/test_backup.c \
  $(TOP)/src/test_btree.c \
  $(TOP)/src/test_config.c \
  $(TOP)/src/test_demovfs.c \
  $(TOP)/src/test_devsym.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_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_stat.c \
  $(TOP)/src/test_tclvar.c \
  $(TOP)/src/test_thread.c \
  $(TOP)/src/test_vfs.c \

  $(TOP)/src/test_wsd.c       \
  $(TOP)/ext/fts3/fts3_term.c \
  $(TOP)/ext/fts3/fts3_test.c 

# Statically linked extensions
#
TESTSRC += \
  $(TOP)/ext/misc/amatch.c \
  $(TOP)/ext/misc/closure.c \
  $(TOP)/ext/misc/fuzzer.c \
  $(TOP)/ext/misc/ieee754.c \
  $(TOP)/ext/misc/nextchar.c \
  $(TOP)/ext/misc/regexp.c \
  $(TOP)/ext/misc/spellfix.c \
  $(TOP)/ext/misc/wholenumber.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 \

		-version-info "8:6:8" \
		-avoid-version

sqlite3$(TEXE):	$(TOP)/src/shell.c libsqlite3.la sqlite3.h
	$(LTLINK) $(READLINE_FLAGS) \
		-o $@ $(TOP)/src/shell.c libsqlite3.la \
		$(LIBREADLINE) $(TLIBS) -rpath "$(libdir)"

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


# This target creates a directory named "tsrc" and fills it with
# copies of all of the C source code and header files needed to
# build on the target system.  Some of the C source code and header
# files are automatically generated.  This target takes care of
# all that automatic generation.
#
.target_source:	$(SRC) $(TOP)/tool/vdbe-compress.tcl
	rm -rf tsrc
	mkdir tsrc
	cp -f $(SRC) tsrc
	rm tsrc/sqlite.h.in tsrc/parse.y
	$(TCLSH_CMD) $(TOP)/tool/vdbe-compress.tcl <tsrc/vdbe.c >vdbe.new
	mv vdbe.new tsrc/vdbe.c
	touch .target_source

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

tclsqlite3.c:	sqlite3.c
	echo '#ifndef USE_SYSTEM_SQLITE' >tclsqlite3.c
	cat sqlite3.c >>tclsqlite3.c
	echo '#endif /* USE_SYSTEM_SQLITE */' >>tclsqlite3.c
	cat $(TOP)/src/tclsqlite.c >>tclsqlite3.c

fts3_tokenizer.lo:	$(TOP)/ext/fts3/fts3_tokenizer.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) -DSQLITE_CORE -c $(TOP)/ext/fts3/fts3_tokenizer.c

fts3_tokenizer1.lo:	$(TOP)/ext/fts3/fts3_tokenizer1.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) -DSQLITE_CORE -c $(TOP)/ext/fts3/fts3_tokenizer1.c

fts3_tokenizer_vtab.lo:	$(TOP)/ext/fts3/fts3_tokenizer_vtab.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) -DSQLITE_CORE -c $(TOP)/ext/fts3/fts3_tokenizer_vtab.c

fts3_unicode.lo:	$(TOP)/ext/fts3/fts3_unicode.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) -DSQLITE_CORE -c $(TOP)/ext/fts3/fts3_unicode.c

fts3_unicode2.lo:	$(TOP)/ext/fts3/fts3_unicode2.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) -DSQLITE_CORE -c $(TOP)/ext/fts3/fts3_unicode2.c

fts3_write.lo:	$(TOP)/ext/fts3/fts3_write.c $(HDR) $(EXTHDR)

#
TESTFIXTURE_FLAGS  = -DTCLSH=1 -DSQLITE_TEST=1 -DSQLITE_CRASH_TEST=1
TESTFIXTURE_FLAGS += -DSQLITE_SERVER=1 -DSQLITE_PRIVATE="" -DSQLITE_CORE 
TESTFIXTURE_FLAGS += -DBUILD_sqlite

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)
	$(LTLINK) -DSQLITE_NO_SYNC=1 $(TEMP_STORE) $(TESTFIXTURE_FLAGS) \
		-o $@ $(TESTFIXTURE_SRC) $(LIBTCL) $(TLIBS)


fulltest:	testfixture$(TEXE) sqlite3$(TEXE)

	rm -f *.da *.bb *.bbg gmon.out
	rm -rf quota2a quota2b quota2c
	rm -rf tsrc .target_source
	rm -f tclsqlite3$(TEXE)
	rm -f testfixture$(TEXE) test.db
	rm -f sqlite3.dll sqlite3.lib sqlite3.exp sqlite3.def
	rm -f sqlite3.c
	rm -f sqlite3rc.h
	rm -f shell.c sqlite3ext.h
	rm -f sqlite3_analyzer$(TEXE) sqlite3_analyzer.c
	rm -f sqlite-*-output.vsix
	rm -f mptester mptester.exe

distclean:	clean
	rm -f config.log config.status libtool Makefile sqlite3.pc

#
# Windows section
#

#
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 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 \
         func.lo global.lo hash.lo \
         icu.lo insert.lo journal.lo legacy.lo loadext.lo \
         main.lo malloc.lo mem0.lo mem1.lo mem2.lo mem3.lo mem5.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 \

  $(TOP)\ext\fts3\fts3_hash.h \
  $(TOP)\ext\fts3\fts3_icu.c \
  $(TOP)\ext\fts3\fts3_porter.c \
  $(TOP)\ext\fts3\fts3_snippet.c \
  $(TOP)\ext\fts3\fts3_tokenizer.h \
  $(TOP)\ext\fts3\fts3_tokenizer.c \
  $(TOP)\ext\fts3\fts3_tokenizer1.c \
  $(TOP)\ext\fts3\fts3_tokenize_vtab.c \
  $(TOP)\ext\fts3\fts3_unicode.c \
  $(TOP)\ext\fts3\fts3_unicode2.c \
  $(TOP)\ext\fts3\fts3_write.c
SRC = $(SRC) \
  $(TOP)\ext\icu\sqliteicu.h \
  $(TOP)\ext\icu\icu.c
SRC = $(SRC) \

  $(TOP)\src\test_backup.c \
  $(TOP)\src\test_btree.c \
  $(TOP)\src\test_config.c \
  $(TOP)\src\test_demovfs.c \
  $(TOP)\src\test_devsym.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_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_stat.c \
  $(TOP)\src\test_tclvar.c \
  $(TOP)\src\test_thread.c \
  $(TOP)\src\test_vfs.c \

  $(TOP)\src\test_wsd.c \
  $(TOP)\ext\fts3\fts3_term.c \
  $(TOP)\ext\fts3\fts3_test.c

# Statically linked extensions
#
TESTEXT = \
  $(TOP)\ext\misc\amatch.c \
  $(TOP)\ext\misc\closure.c \
  $(TOP)\ext\misc\fuzzer.c \
  $(TOP)\ext\misc\ieee754.c \
  $(TOP)\ext\misc\nextchar.c \
  $(TOP)\ext\misc\regexp.c \
  $(TOP)\ext\misc\spellfix.c \
  $(TOP)\ext\misc\wholenumber.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\vdbetrace.c \
  $(TOP)\src\where.c \
  parse.c \
  $(TOP)\ext\fts3\fts3.c \
  $(TOP)\ext\fts3\fts3_aux.c \
  $(TOP)\ext\fts3\fts3_expr.c \
  $(TOP)\ext\fts3\fts3_tokenizer.c \
  $(TOP)\ext\fts3\fts3_tokenize_vtab.c \
  $(TOP)\ext\fts3\fts3_unicode.c \
  $(TOP)\ext\fts3\fts3_unicode2.c \
  $(TOP)\ext\fts3\fts3_write.c \
  $(TOP)\ext\async\sqlite3async.c

# Header files used by all library source files.
#

	$(LTLIB) $(LTLIBOPTS) $(LTLIBPATHS) /OUT:$@ tclsqlite.lo libsqlite3.lib $(LIBTCL:tcl=tclstub) $(TLIBS)

sqlite3.exe:	$(TOP)\src\shell.c libsqlite3.lib $(LIBRESOBJS) sqlite3.h
	$(LTLINK) $(READLINE_FLAGS) \
		$(TOP)\src\shell.c \
		/link $(LTLINKOPTS) $(LTLIBPATHS) libsqlite3.lib $(LIBRESOBJS) $(LIBREADLINE) $(LTLIBS) $(TLIBS)

mptester.exe:	$(TOP)\mptest\mptest.c libsqlite3.lib $(LIBRESOBJS) sqlite3.h
	$(LTLINK) $(TOP)\mptest\mptest.c \
		/link $(LTLINKOPTS) $(LTLIBPATHS) libsqlite3.lib $(LIBRESOBJS) $(LIBREADLINE) $(LTLIBS) $(TLIBS)

# This target creates a directory named "tsrc" and fills it with
# copies of all of the C source code and header files needed to
# build on the target system.  Some of the C source code and header
# files are automatically generated.  This target takes care of
# all that automatic generation.
#
.target_source:	$(SRC) $(TOP)\tool\vdbe-compress.tcl
	-rmdir /S/Q tsrc
	-mkdir tsrc
	for %i in ($(SRC)) do copy /Y %i tsrc
	del /Q tsrc\sqlite.h.in tsrc\parse.y
	$(TCLSH_CMD) $(TOP)\tool\vdbe-compress.tcl < tsrc\vdbe.c > vdbe.new
	move vdbe.new tsrc\vdbe.c
	echo > .target_source

sqlite3.c:	.target_source $(TOP)\tool\mksqlite3c.tcl
	$(TCLSH_CMD) $(TOP)\tool\mksqlite3c.tcl
	copy tsrc\shell.c .
	copy tsrc\sqlite3ext.h .

sqlite3-all.c:	sqlite3.c $(TOP)\tool\split-sqlite3c.tcl
	$(TCLSH_CMD) $(TOP)\tool\split-sqlite3c.tcl

# Rule to build the amalgamation
#
sqlite3.lo:	sqlite3.c

fts3_tokenizer.lo:	$(TOP)\ext\fts3\fts3_tokenizer.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) -DSQLITE_CORE -c $(TOP)\ext\fts3\fts3_tokenizer.c

fts3_tokenizer1.lo:	$(TOP)\ext\fts3\fts3_tokenizer1.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) -DSQLITE_CORE -c $(TOP)\ext\fts3\fts3_tokenizer1.c

fts3_tokenize_vtab.lo:	$(TOP)\ext\fts3\fts3_tokenize_vtab.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) -DSQLITE_CORE -c $(TOP)\ext\fts3\fts3_tokenize_vtab.c

fts3_unicode.lo:	$(TOP)\ext\fts3\fts3_unicode.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) -DSQLITE_CORE -c $(TOP)\ext\fts3\fts3_unicode.c

fts3_unicode2.lo:	$(TOP)\ext\fts3\fts3_unicode2.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) -DSQLITE_CORE -c $(TOP)\ext\fts3\fts3_unicode2.c

fts3_write.lo:	$(TOP)\ext\fts3\fts3_write.c $(HDR) $(EXTHDR)

# 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=1 -DSQLITE_TEST=1 -DSQLITE_CRASH_TEST=1
TESTFIXTURE_FLAGS = $(TESTFIXTURE_FLAGS) -DSQLITE_SERVER=1 -DSQLITE_PRIVATE="" -DSQLITE_CORE

TESTFIXTURE_SRC0 = $(TESTEXT) $(TESTSRC2) libsqlite3.lib
TESTFIXTURE_SRC1 = $(TESTEXT) sqlite3.c
!IF $(USE_AMALGAMATION)==0
TESTFIXTURE_SRC = $(TESTSRC) $(TOP)\src\tclsqlite.c $(TESTFIXTURE_SRC0)
!ELSE
TESTFIXTURE_SRC = $(TESTSRC) $(TOP)\src\tclsqlite.c $(TESTFIXTURE_SRC1)
!ENDIF

testfixture.exe:	$(TESTFIXTURE_SRC) $(LIBRESOBJS) $(HDR)

	-rmdir /Q/S tsrc
	del /Q .target_source
	del /Q tclsqlite3.exe tclsqlite3.exp
	del /Q testfixture.exe testfixture.exp test.db
	del /Q sqlite3.dll sqlite3.lib sqlite3.exp sqlite3.def
	del /Q sqlite3.c
	del /Q sqlite3rc.h
	del /Q shell.c sqlite3ext.h
	del /Q sqlite3_analyzer.exe sqlite3_analyzer.exp sqlite3_analyzer.c
	del /Q sqlite-*-output.vsix
	del /Q mptester.exe

# Dynamic link library section.
#
dll: sqlite3.dll

sqlite3.def: libsqlite3.lib
	echo EXPORTS > sqlite3.def
	dumpbin /all libsqlite3.lib \
		| $(NAWK) "/ 1 _?sqlite3_/ { sub(/^.* _?/,\"\");print }" \
		| sort >> sqlite3.def

sqlite3.dll: $(LIBOBJ) $(LIBRESOBJS) sqlite3.def
	$(LD) $(LDFLAGS) $(LTLINKOPTS) $(LTLIBPATHS) /DLL /DEF:sqlite3.def /OUT:$@ $(LIBOBJ) $(LIBRESOBJS) $(LTLIBS) $(TLIBS)

	rm -f lemon lempar.c parse.* sqlite*.tar.gz mkkeywordhash keywordhash.h
	rm -f $(PUBLISH)
	rm -f *.da *.bb *.bbg gmon.out
	rm -rf quota2a quota2b quota2c
	rm -rf tsrc target_source
	rm -f testloadext.dll libtestloadext.so
	rm -f sqlite3.c fts?amal.c tclsqlite3.c
	rm -f sqlite3rc.h
	rm -f shell.c sqlite3ext.h
	rm -f $(SHPREFIX)sqlite3.$(SO)

3.7.17

#! /bin/sh
# Guess values for system-dependent variables and create Makefiles.
# Generated by GNU Autoconf 2.62 for sqlite 3.7.17.
#
# Copyright (C) 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001,
# 2002, 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
# This configure script is free software; the Free Software Foundation
# gives unlimited permission to copy, distribute and modify it.
## --------------------- ##
## M4sh Initialization.  ##

MFLAGS=
MAKEFLAGS=
SHELL=${CONFIG_SHELL-/bin/sh}

# Identity of this package.
PACKAGE_NAME='sqlite'
PACKAGE_TARNAME='sqlite'
PACKAGE_VERSION='3.7.17'
PACKAGE_STRING='sqlite 3.7.17'
PACKAGE_BUGREPORT=''

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

#
# 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 3.7.17 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 3.7.17:";;
   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]

    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 3.7.17
generated by GNU Autoconf 2.62

Copyright (C) 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001,
2002, 2003, 2004, 2005, 2006, 2007, 2008 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
fi
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 3.7.17, which was
generated by GNU Autoconf 2.62.  Invocation command line was

  $ $0 $@

_ACEOF
exec 5>>config.log
{

exec 6>&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 3.7.17, which was
generated by GNU Autoconf 2.62.  Invocation command line was

  CONFIG_FILES    = $CONFIG_FILES
  CONFIG_HEADERS  = $CONFIG_HEADERS
  CONFIG_LINKS    = $CONFIG_LINKS
  CONFIG_COMMANDS = $CONFIG_COMMANDS
  $ $0 $@

$config_commands

Report bugs to <bug-autoconf@gnu.org>."

_ACEOF
cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
ac_cs_version="\\
sqlite config.status 3.7.17
configured by $0, generated by GNU Autoconf 2.62,
  with options \\"`$as_echo "$ac_configure_args" | sed 's/^ //; s/[\\""\`\$]/\\\\&/g'`\\"

Copyright (C) 2008 Free Software Foundation, Inc.
This config.status script is free software; the Free Software Foundation
gives unlimited permission to copy, distribute and modify it."

/*
** 2001 September 22
**
** 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.
**
*************************************************************************
** This is the header file for the generic hash-table implementation
** used in SQLite.  We've modified it slightly to serve as a standalone
** hash table implementation for the full-text indexing module.
**
*/
#ifndef _HASH_H_
#define _HASH_H_

/*
** 2001 September 22
**
** 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.
**
*************************************************************************
** This is the header file for the generic hash-table implementation
** used in SQLite.  We've modified it slightly to serve as a standalone
** hash table implementation for the full-text indexing module.
**
*/
#ifndef _FTS1_HASH_H_
#define _FTS1_HASH_H_

void sqlite3Fts2SimpleTokenizerModule(sqlite3_tokenizer_module const**ppModule);
void sqlite3Fts2PorterTokenizerModule(sqlite3_tokenizer_module const**ppModule);
void sqlite3Fts2IcuTokenizerModule(sqlite3_tokenizer_module const**ppModule);

int sqlite3Fts2InitHashTable(sqlite3 *, fts2Hash *, const char *);

/*
** Initialize the fts2 extension. If this extension is built as part
** of the sqlite library, then this function is called directly by
** SQLite. If fts2 is built as a dynamically loadable extension, this
** function is called by the sqlite3_extension_init() entry point.
*/
int sqlite3Fts2Init(sqlite3 *db){
  int rc = SQLITE_OK;
  fts2Hash *pHash = 0;
  const sqlite3_tokenizer_module *pSimple = 0;
  const sqlite3_tokenizer_module *pPorter = 0;
  const sqlite3_tokenizer_module *pIcu = 0;

  sqlite3Fts2SimpleTokenizerModule(&pSimple);
  sqlite3Fts2PorterTokenizerModule(&pPorter);
#ifdef SQLITE_ENABLE_ICU
  sqlite3Fts2IcuTokenizerModule(&pIcu);
#endif

  /* Allocate and initialize the hash-table used to store tokenizers. */
  pHash = sqlite3_malloc(sizeof(fts2Hash));
  if( !pHash ){
    rc = SQLITE_NOMEM;
  }else{
    sqlite3Fts2HashInit(pHash, FTS2_HASH_STRING, 1);
  }

/*
** 2001 September 22
**
** 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.
**
*************************************************************************
** This is the header file for the generic hash-table implementation
** used in SQLite.  We've modified it slightly to serve as a standalone
** hash table implementation for the full-text indexing module.
**
*/
#ifndef _FTS2_HASH_H_
#define _FTS2_HASH_H_

}

#endif

/*
** Set up SQL objects in database db used to access the contents of
** the hash table pointed to by argument pHash. The hash table must
** been initialized to use string keys, and to take a private copy 
** of the key when a value is inserted. i.e. by a call similar to:
**
**    sqlite3Fts2HashInit(pHash, FTS2_HASH_STRING, 1);
**
** This function adds a scalar function (see header comment above
** scalarFunc() in this file for details) and, if ENABLE_TABLE is
** defined at compilation time, a temporary virtual table (see header 

  **
  ** then argc is set to 2, and the argv[] array contains pointers
  ** to the strings "arg1" and "arg2".
  **
  ** This method should return either SQLITE_OK (0), or an SQLite error 
  ** code. If SQLITE_OK is returned, then *ppTokenizer should be set
  ** to point at the newly created tokenizer structure. The generic
  ** sqlite3_tokenizer.pModule variable should not be initialized by
  ** this callback. The caller will do so.
  */
  int (*xCreate)(
    int argc,                           /* Size of argv array */
    const char *const*argv,             /* Tokenizer argument strings */
    sqlite3_tokenizer **ppTokenizer     /* OUT: Created tokenizer */
  );

      sqlite3_bind_int64(pCsr->pStmt, 1, pCsr->iPrevId);
      pCsr->isRequireSeek = 0;
      if( SQLITE_ROW==sqlite3_step(pCsr->pStmt) ){
        return SQLITE_OK;
      }else{
        rc = sqlite3_reset(pCsr->pStmt);
        if( rc==SQLITE_OK && ((Fts3Table *)pCsr->base.pVtab)->zContentTbl==0 ){
          /* If no row was found and no error has occurred, then the %_content
          ** table is missing a row that is present in the full-text index.
          ** The data structures are corrupt.  */
          rc = FTS_CORRUPT_VTAB;
          pCsr->isEof = 1;
        }
      }
    }

*/
static void fts3SegReaderCursorFree(Fts3MultiSegReader *pSegcsr){
  sqlite3Fts3SegReaderFinish(pSegcsr);
  sqlite3_free(pSegcsr);
}

/*
** This function retrieves the doclist for the specified term (or term
** prefix) from the database.
*/
static int fts3TermSelect(
  Fts3Table *p,                   /* Virtual table handle */
  Fts3PhraseToken *pTok,          /* Token to query for */
  int iColumn,                    /* Column to query (or -ve for all columns) */
  int *pnOut,                     /* OUT: Size of buffer at *ppOut */

    if( zQuery==0 && sqlite3_value_type(apVal[0])!=SQLITE_NULL ){
      return SQLITE_NOMEM;
    }

    pCsr->iLangid = 0;
    if( nVal==2 ) pCsr->iLangid = sqlite3_value_int(apVal[1]);

    assert( p->base.zErrMsg==0 );
    rc = sqlite3Fts3ExprParse(p->pTokenizer, pCsr->iLangid,
        p->azColumn, p->bFts4, p->nColumn, iCol, zQuery, -1, &pCsr->pExpr, 
        &p->base.zErrMsg
    );
    if( rc!=SQLITE_OK ){




      return rc;
    }

    rc = sqlite3Fts3ReadLock(p);
    if( rc!=SQLITE_OK ) return rc;

    rc = fts3EvalStart(pCsr);

void sqlite3Fts3UnicodeTokenizer(sqlite3_tokenizer_module const**ppModule);
#endif
#ifdef SQLITE_ENABLE_ICU
void sqlite3Fts3IcuTokenizerModule(sqlite3_tokenizer_module const**ppModule);
#endif

/*
** Initialize the fts3 extension. If this extension is built as part
** of the sqlite library, then this function is called directly by
** SQLite. If fts3 is built as a dynamically loadable extension, this
** function is called by the sqlite3_extension_init() entry point.
*/
int sqlite3Fts3Init(sqlite3 *db){
  int rc = SQLITE_OK;
  Fts3Hash *pHash = 0;

  rc = sqlite3Fts3InitAux(db);
  if( rc!=SQLITE_OK ) return rc;

  sqlite3Fts3SimpleTokenizerModule(&pSimple);
  sqlite3Fts3PorterTokenizerModule(&pPorter);

  /* Allocate and initialize the hash-table used to store tokenizers. */
  pHash = sqlite3_malloc(sizeof(Fts3Hash));
  if( !pHash ){
    rc = SQLITE_NOMEM;
  }else{
    sqlite3Fts3HashInit(pHash, FTS3_HASH_STRING, 1);
  }

        db, "fts3", &fts3Module, (void *)pHash, hashDestroy
    );
    if( rc==SQLITE_OK ){
      rc = sqlite3_create_module_v2(
          db, "fts4", &fts3Module, (void *)pHash, 0
      );
    }
    if( rc==SQLITE_OK ){
      rc = sqlite3Fts3InitTok(db, (void *)pHash);
    }
    return rc;
  }


  /* An error has occurred. Delete the hash table and return the error code. */
  assert( rc!=SQLITE_OK );
  if( pHash ){
    sqlite3Fts3HashClear(pHash);
    sqlite3_free(pHash);
  }

** must be of type FTSQUERY_PHRASE. 
**
** The returned value is either NULL or a pointer to a buffer containing
** a position-list indicating the occurrences of the phrase in column iCol
** of the current row. 
**
** More specifically, the returned buffer contains 1 varint for each 
** occurrence of the phrase in the column, stored using the normal (delta+2) 
** compression and is terminated by either an 0x01 or 0x00 byte. For example,
** if the requested column contains "a b X c d X X" and the position-list
** for 'X' is requested, the buffer returned may contain:
**
**     0x04 0x05 0x03 0x01   or   0x04 0x05 0x03 0x00
**
** This function works regardless of whether or not the phrase is deferred,

void sqlite3Fts3Snippet(sqlite3_context *, Fts3Cursor *, const char *,
  const char *, const char *, int, int
);
void sqlite3Fts3Matchinfo(sqlite3_context *, Fts3Cursor *, const char *);

/* fts3_expr.c */
int sqlite3Fts3ExprParse(sqlite3_tokenizer *, int,
  char **, int, int, int, const char *, int, Fts3Expr **, char **
);
void sqlite3Fts3ExprFree(Fts3Expr *);
#ifdef SQLITE_TEST
int sqlite3Fts3ExprInitTestInterface(sqlite3 *db);
int sqlite3Fts3InitTerm(sqlite3 *db);
#endif

    Fts3Table*, Fts3MultiSegReader*, int, const char*, int);
int sqlite3Fts3MsrIncrNext(
    Fts3Table *, Fts3MultiSegReader *, sqlite3_int64 *, char **, int *);
int sqlite3Fts3EvalPhrasePoslist(Fts3Cursor *, Fts3Expr *, int iCol, char **); 
int sqlite3Fts3MsrOvfl(Fts3Cursor *, Fts3MultiSegReader *, int *);
int sqlite3Fts3MsrIncrRestart(Fts3MultiSegReader *pCsr);

/* fts3_tokenize_vtab.c */
int sqlite3Fts3InitTok(sqlite3*, Fts3Hash *);

/* fts3_unicode2.c (functions generated by parsing unicode text files) */
#ifdef SQLITE_ENABLE_FTS4_UNICODE61
int sqlite3FtsUnicodeFold(int, int);
int sqlite3FtsUnicodeIsalnum(int);
int sqlite3FtsUnicodeIsdiacritic(int);
#endif

#endif /* !SQLITE_CORE || SQLITE_ENABLE_FTS3 */
#endif /* _FTSINT_H */

  int nFts3;                      /* Result of strlen(zFts3) */
  int nByte;                      /* Bytes of space to allocate here */
  int rc;                         /* value returned by declare_vtab() */
  Fts3auxTable *p;                /* Virtual table object to return */

  UNUSED_PARAMETER(pUnused);

  /* The user should invoke this in one of two forms:
  **
  **     CREATE VIRTUAL TABLE xxx USING fts4aux(fts4-table);
  **     CREATE VIRTUAL TABLE xxx USING fts4aux(fts4-table-db, fts4-table);
  */
  if( argc!=4 && argc!=5 ) goto bad_args;






  zDb = argv[1]; 
  nDb = (int)strlen(zDb);
  if( argc==5 ){
    if( nDb==4 && 0==sqlite3_strnicmp("temp", zDb, 4) ){
      zDb = argv[3]; 
      nDb = (int)strlen(zDb);
      zFts3 = argv[4];
    }else{
      goto bad_args;
    }
  }else{
  zFts3 = argv[3];
  }
  nFts3 = (int)strlen(zFts3);

  rc = sqlite3_declare_vtab(db, FTS3_TERMS_SCHEMA);
  if( rc!=SQLITE_OK ) return rc;

  nByte = sizeof(Fts3auxTable) + sizeof(Fts3Table) + nDb + nFts3 + 2;
  p = (Fts3auxTable *)sqlite3_malloc(nByte);

  memcpy((char *)p->pFts3Tab->zDb, zDb, nDb);
  memcpy((char *)p->pFts3Tab->zName, zFts3, nFts3);
  sqlite3Fts3Dequote((char *)p->pFts3Tab->zName);

  *ppVtab = (sqlite3_vtab *)p;
  return SQLITE_OK;

 bad_args:
  *pzErr = sqlite3_mprintf("invalid arguments to fts4aux constructor");
  return SQLITE_ERROR;
}

/*
** This function does the work for both the xDisconnect and xDestroy methods.
** These tables have no persistent representation of their own, so xDisconnect
** and xDestroy are identical operations.
*/

  int nNest;                          /* Number of nested brackets */
};

/*
** This function is equivalent to the standard isspace() function. 
**
** The standard isspace() can be awkward to use safely, because although it
** is defined to accept an argument of type int, its behavior when passed
** an integer that falls outside of the range of the unsigned char type
** is undefined (and sometimes, "undefined" means segfault). This wrapper
** is defined to accept an argument of type char, and always returns 0 for
** any values that fall outside of the range of the unsigned char type (i.e.
** negative values).
*/
static int fts3isspace(char c){

        if( !pNot ){
          sqlite3Fts3ExprFree(p);
          rc = SQLITE_NOMEM;
          goto exprparse_out;
        }
        pNot->eType = FTSQUERY_NOT;
        pNot->pRight = p;
        p->pParent = pNot;
        if( pNotBranch ){
          pNot->pLeft = pNotBranch;
          pNotBranch->pParent = pNot;
        }
        pNotBranch = pNot;
        p = pPrev;
      }else{
        int eType = p->eType;
        isPhrase = (eType==FTSQUERY_PHRASE || p->pLeft);

        rc = SQLITE_ERROR;
      }else{
        Fts3Expr *pIter = pNotBranch;
        while( pIter->pLeft ){
          pIter = pIter->pLeft;
        }
        pIter->pLeft = pRet;
        pRet->pParent = pIter;
        pRet = pNotBranch;
      }
    }
  }
  *pnConsumed = n - nIn;

exprparse_out:
  if( rc!=SQLITE_OK ){
    sqlite3Fts3ExprFree(pRet);
    sqlite3Fts3ExprFree(pNotBranch);
    pRet = 0;
  }
  *ppExpr = pRet;
  return rc;
}

/*
** Return SQLITE_ERROR if the maximum depth of the expression tree passed 
** as the only argument is more than nMaxDepth.
*/
static int fts3ExprCheckDepth(Fts3Expr *p, int nMaxDepth){
  int rc = SQLITE_OK;
  if( p ){
    if( nMaxDepth<0 ){ 
      rc = SQLITE_TOOBIG;
    }else{
      rc = fts3ExprCheckDepth(p->pLeft, nMaxDepth-1);
      if( rc==SQLITE_OK ){
        rc = fts3ExprCheckDepth(p->pRight, nMaxDepth-1);
      }
    }
  }
  return rc;
}

/*
** This function attempts to transform the expression tree at (*pp) to
** an equivalent but more balanced form. The tree is modified in place.
** If successful, SQLITE_OK is returned and (*pp) set to point to the 
** new root expression node. 
**
** nMaxDepth is the maximum allowable depth of the balanced sub-tree.
**
** Otherwise, if an error occurs, an SQLite error code is returned and 
** expression (*pp) freed.
*/
static int fts3ExprBalance(Fts3Expr **pp, int nMaxDepth){
  int rc = SQLITE_OK;             /* Return code */
  Fts3Expr *pRoot = *pp;          /* Initial root node */
  Fts3Expr *pFree = 0;            /* List of free nodes. Linked by pParent. */
  int eType = pRoot->eType;       /* Type of node in this tree */

  if( nMaxDepth==0 ){
    rc = SQLITE_ERROR;
  }

  if( rc==SQLITE_OK && (eType==FTSQUERY_AND || eType==FTSQUERY_OR) ){
    Fts3Expr **apLeaf;
    apLeaf = (Fts3Expr **)sqlite3_malloc(sizeof(Fts3Expr *) * nMaxDepth);
    if( 0==apLeaf ){
      rc = SQLITE_NOMEM;
    }else{
      memset(apLeaf, 0, sizeof(Fts3Expr *) * nMaxDepth);
    }

    if( rc==SQLITE_OK ){
      int i;
      Fts3Expr *p;

      /* Set $p to point to the left-most leaf in the tree of eType nodes. */
      for(p=pRoot; p->eType==eType; p=p->pLeft){
        assert( p->pParent==0 || p->pParent->pLeft==p );
        assert( p->pLeft && p->pRight );
      }

      /* This loop runs once for each leaf in the tree of eType nodes. */
      while( 1 ){
        int iLvl;
        Fts3Expr *pParent = p->pParent;     /* Current parent of p */

        assert( pParent==0 || pParent->pLeft==p );
        p->pParent = 0;
        if( pParent ){
          pParent->pLeft = 0;
        }else{
          pRoot = 0;
        }
        rc = fts3ExprBalance(&p, nMaxDepth-1);
        if( rc!=SQLITE_OK ) break;

        for(iLvl=0; p && iLvl<nMaxDepth; iLvl++){
          if( apLeaf[iLvl]==0 ){
            apLeaf[iLvl] = p;
            p = 0;
          }else{
            assert( pFree );
            pFree->pLeft = apLeaf[iLvl];
            pFree->pRight = p;
            pFree->pLeft->pParent = pFree;
            pFree->pRight->pParent = pFree;

            p = pFree;
            pFree = pFree->pParent;
            p->pParent = 0;
            apLeaf[iLvl] = 0;
          }
        }
        if( p ){
          sqlite3Fts3ExprFree(p);
          rc = SQLITE_TOOBIG;
          break;
        }

        /* If that was the last leaf node, break out of the loop */
        if( pParent==0 ) break;

        /* Set $p to point to the next leaf in the tree of eType nodes */
        for(p=pParent->pRight; p->eType==eType; p=p->pLeft);

        /* Remove pParent from the original tree. */
        assert( pParent->pParent==0 || pParent->pParent->pLeft==pParent );
        pParent->pRight->pParent = pParent->pParent;
        if( pParent->pParent ){
          pParent->pParent->pLeft = pParent->pRight;
        }else{
          assert( pParent==pRoot );
          pRoot = pParent->pRight;
        }

        /* Link pParent into the free node list. It will be used as an
        ** internal node of the new tree.  */
        pParent->pParent = pFree;
        pFree = pParent;
      }

      if( rc==SQLITE_OK ){
        p = 0;
        for(i=0; i<nMaxDepth; i++){
          if( apLeaf[i] ){
            if( p==0 ){
              p = apLeaf[i];
              p->pParent = 0;
            }else{
              assert( pFree!=0 );
              pFree->pRight = p;
              pFree->pLeft = apLeaf[i];
              pFree->pLeft->pParent = pFree;
              pFree->pRight->pParent = pFree;

              p = pFree;
              pFree = pFree->pParent;
              p->pParent = 0;
            }
          }
        }
        pRoot = p;
      }else{
        /* An error occurred. Delete the contents of the apLeaf[] array 
        ** and pFree list. Everything else is cleaned up by the call to
        ** sqlite3Fts3ExprFree(pRoot) below.  */
        Fts3Expr *pDel;
        for(i=0; i<nMaxDepth; i++){
          sqlite3Fts3ExprFree(apLeaf[i]);
        }
        while( (pDel=pFree)!=0 ){
          pFree = pDel->pParent;
          sqlite3_free(pDel);
        }
      }

      assert( pFree==0 );
      sqlite3_free( apLeaf );
    }
  }

  if( rc!=SQLITE_OK ){
    sqlite3Fts3ExprFree(pRoot);
    pRoot = 0;
  }
  *pp = pRoot;
  return rc;
}

/*
** This function is similar to sqlite3Fts3ExprParse(), with the following
** differences:
**
**   1. It does not do expression rebalancing.
**   2. It does not check that the expression does not exceed the 
**      maximum allowable depth.
**   3. Even if it fails, *ppExpr may still be set to point to an 
**      expression tree. It should be deleted using sqlite3Fts3ExprFree()
**      in this case.
*/
static int fts3ExprParseUnbalanced(
  sqlite3_tokenizer *pTokenizer,      /* Tokenizer module */
  int iLangid,                        /* Language id for tokenizer */
  char **azCol,                       /* Array of column names for fts3 table */
  int bFts4,                          /* True to allow FTS4-only syntax */
  int nCol,                           /* Number of entries in azCol[] */
  int iDefaultCol,                    /* Default column to query */
  const char *z, int n,               /* Text of MATCH query */
  Fts3Expr **ppExpr                   /* OUT: Parsed query structure */
){
  int nParsed;
  int rc;
  ParseContext sParse;

  memset(&sParse, 0, sizeof(ParseContext));
  sParse.pTokenizer = pTokenizer;
  sParse.iLangid = iLangid;
  sParse.azCol = (const char **)azCol;
  sParse.nCol = nCol;
  sParse.iDefaultCol = iDefaultCol;
  sParse.bFts4 = bFts4;
  if( z==0 ){
    *ppExpr = 0;
    return SQLITE_OK;
  }
  if( n<0 ){
    n = (int)strlen(z);
  }
  rc = fts3ExprParse(&sParse, z, n, ppExpr, &nParsed);
  assert( rc==SQLITE_OK || *ppExpr==0 );

  /* Check for mismatched parenthesis */
  if( rc==SQLITE_OK && sParse.nNest ){
    rc = SQLITE_ERROR;
  }
  
  return rc;
}

/*
** Parameters z and n contain a pointer to and length of a buffer containing
** an fts3 query expression, respectively. This function attempts to parse the
** query expression and create a tree of Fts3Expr structures representing the
** parsed expression. If successful, *ppExpr is set to point to the head
** of the parsed expression tree and SQLITE_OK is returned. If an error

  sqlite3_tokenizer *pTokenizer,      /* Tokenizer module */
  int iLangid,                        /* Language id for tokenizer */
  char **azCol,                       /* Array of column names for fts3 table */
  int bFts4,                          /* True to allow FTS4-only syntax */
  int nCol,                           /* Number of entries in azCol[] */
  int iDefaultCol,                    /* Default column to query */
  const char *z, int n,               /* Text of MATCH query */
  Fts3Expr **ppExpr,                  /* OUT: Parsed query structure */
  char **pzErr                        /* OUT: Error message (sqlite3_malloc) */
){
  static const int MAX_EXPR_DEPTH = 12;
  int rc = fts3ExprParseUnbalanced(

      pTokenizer, iLangid, azCol, bFts4, nCol, iDefaultCol, z, n, ppExpr
  );



  /* Rebalance the expression. And check that its depth does not exceed
  ** MAX_EXPR_DEPTH.  */



  if( rc==SQLITE_OK && *ppExpr ){
    rc = fts3ExprBalance(ppExpr, MAX_EXPR_DEPTH);
    if( rc==SQLITE_OK ){
      rc = fts3ExprCheckDepth(*ppExpr, MAX_EXPR_DEPTH);
  }


  }



  if( rc!=SQLITE_OK ){

    sqlite3Fts3ExprFree(*ppExpr);
    *ppExpr = 0;
    if( rc==SQLITE_TOOBIG ){
      *pzErr = sqlite3_mprintf(
          "FTS expression tree is too large (maximum depth %d)", MAX_EXPR_DEPTH
      );
      rc = SQLITE_ERROR;
    }else if( rc==SQLITE_ERROR ){
      *pzErr = sqlite3_mprintf("malformed MATCH expression: [%s]", z);
    }
  }

  return rc;
}

/*
** Free a single node of an expression tree.
*/
static void fts3FreeExprNode(Fts3Expr *p){

    assert( p->eType==FTSQUERY_PHRASE || p->pPhrase==0 );


    sqlite3Fts3EvalPhraseCleanup(p->pPhrase);
    sqlite3_free(p->aMI);
    sqlite3_free(p);
  }

/*
** Free a parsed fts3 query expression allocated by sqlite3Fts3ExprParse().
**
** This function would be simpler if it recursively called itself. But
** that would mean passing a sufficiently large expression to ExprParse()
** could cause a stack overflow.
*/
void sqlite3Fts3ExprFree(Fts3Expr *pDel){
  Fts3Expr *p;
  assert( pDel==0 || pDel->pParent==0 );
  for(p=pDel; p && (p->pLeft||p->pRight); p=(p->pLeft ? p->pLeft : p->pRight)){
    assert( p->pParent==0 || p==p->pParent->pRight || p==p->pParent->pLeft );
  }
  while( p ){
    Fts3Expr *pParent = p->pParent;
    fts3FreeExprNode(p);
    if( pParent && p==pParent->pLeft && pParent->pRight ){
      p = pParent->pRight;
      while( p && (p->pLeft || p->pRight) ){
        assert( p==p->pParent->pRight || p==p->pParent->pLeft );
        p = (p->pLeft ? p->pLeft : p->pRight);
      }
    }else{
      p = pParent;
    }
  }
}

/****************************************************************************
*****************************************************************************
** Everything after this point is just test code.
*/

** sqlite3_free() to release the memory. If an OOM condition is encountered,
** NULL is returned.
**
** If the second argument is not NULL, then its contents are prepended to 
** the returned expression text and then freed using sqlite3_free().
*/
static char *exprToString(Fts3Expr *pExpr, char *zBuf){
  if( pExpr==0 ){
    return sqlite3_mprintf("");
  }
  switch( pExpr->eType ){
    case FTSQUERY_PHRASE: {
      Fts3Phrase *pPhrase = pExpr->pPhrase;
      int i;
      zBuf = sqlite3_mprintf(
          "%zPHRASE %d 0", zBuf, pPhrase->iColumn);
      for(i=0; zBuf && i<pPhrase->nToken; i++){

    sqlite3_result_error_nomem(context);
    goto exprtest_out;
  }
  for(ii=0; ii<nCol; ii++){
    azCol[ii] = (char *)sqlite3_value_text(argv[ii+2]);
  }

  if( sqlite3_user_data(context) ){
    char *zDummy = 0;
  rc = sqlite3Fts3ExprParse(
        pTokenizer, 0, azCol, 0, nCol, nCol, zExpr, nExpr, &pExpr, &zDummy
    );
    assert( rc==SQLITE_OK || pExpr==0 );
    sqlite3_free(zDummy);
  }else{
    rc = fts3ExprParseUnbalanced(
      pTokenizer, 0, azCol, 0, nCol, nCol, zExpr, nExpr, &pExpr
  );
  }

  if( rc!=SQLITE_OK && rc!=SQLITE_NOMEM ){
    sqlite3Fts3ExprFree(pExpr);
    sqlite3_result_error(context, "Error parsing expression", -1);
  }else if( rc==SQLITE_NOMEM || !(zBuf = exprToString(pExpr, 0)) ){
    sqlite3_result_error_nomem(context);
  }else{
    sqlite3_result_text(context, zBuf, -1, SQLITE_TRANSIENT);
    sqlite3_free(zBuf);
  }

}

/*
** Register the query expression parser test function fts3_exprtest() 
** with database connection db. 
*/
int sqlite3Fts3ExprInitTestInterface(sqlite3* db){
  int rc = sqlite3_create_function(
      db, "fts3_exprtest", -1, SQLITE_UTF8, 0, fts3ExprTest, 0, 0
  );
  if( rc==SQLITE_OK ){
    rc = sqlite3_create_function(db, "fts3_exprtest_rebalance", 
        -1, SQLITE_UTF8, (void *)1, fts3ExprTest, 0, 0
    );
  }
  return rc;
}

#endif
#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */

/*
** 2001 September 22
**
** 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.
**
*************************************************************************
** This is the header file for the generic hash-table implementation
** used in SQLite.  We've modified it slightly to serve as a standalone
** hash table implementation for the full-text indexing module.
**
*/
#ifndef _FTS3_HASH_H_
#define _FTS3_HASH_H_

/*
** Select the fragment of text consisting of nFragment contiguous tokens 
** from column iCol that represent the "best" snippet. The best snippet
** is the snippet with the highest score, where scores are calculated
** by adding:
**
**   (a) +1 point for each occurrence of a matchable phrase in the snippet.
**
**   (b) +1000 points for the first occurrence of each matchable phrase in 
**       the snippet for which the corresponding mCovered bit is not set.
**
** The selected snippet parameters are stored in structure *pFragment before
** returning. The score of the selected snippet is stored in *piScore
** before returning.
*/
static int fts3BestSnippet(

**
** If present, the first argument is the chunksize in bytes to load doclists
** in. The second argument is the minimum doclist size in bytes to use
** incremental loading with.
**
** Whether or not the arguments are present, this command returns a list of
** two integers - the initial chunksize and threshold when the command is
** invoked. This can be used to restore the default behavior after running
** tests. For example:
**
**    # Override incr-load settings for testing:
**    set cfg [fts3_configure_incr_load $new_chunksize $new_threshold]
**
**    .... run tests ....
**

/*
** 2013 Apr 22
**
** 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.
**
******************************************************************************
**
** This file contains code for the "fts3tokenize" virtual table module.
** An fts3tokenize virtual table is created as follows:
**
**   CREATE VIRTUAL TABLE <tbl> USING fts3tokenize(
**       <tokenizer-name>, <arg-1>, ...
**   );
**
** The table created has the following schema:
**
**   CREATE TABLE <tbl>(input, token, start, end, position)
**
** When queried, the query must include a WHERE clause of type:
**
**   input = <string>
**
** The virtual table module tokenizes this <string>, using the FTS3 
** tokenizer specified by the arguments to the CREATE VIRTUAL TABLE 
** statement and returns one row for each token in the result. With
** fields set as follows:
**
**   input:   Always set to a copy of <string>
**   token:   A token from the input.
**   start:   Byte offset of the token within the input <string>.
**   end:     Byte offset of the byte immediately following the end of the
**            token within the input string.
**   pos:     Token offset of token within input.
**
*/
#include "fts3Int.h"
#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)

#include <string.h>
#include <assert.h>

typedef struct Fts3tokTable Fts3tokTable;
typedef struct Fts3tokCursor Fts3tokCursor;

/*
** Virtual table structure.
*/
struct Fts3tokTable {
  sqlite3_vtab base;              /* Base class used by SQLite core */
  const sqlite3_tokenizer_module *pMod;
  sqlite3_tokenizer *pTok;
};

/*
** Virtual table cursor structure.
*/
struct Fts3tokCursor {
  sqlite3_vtab_cursor base;       /* Base class used by SQLite core */
  char *zInput;                   /* Input string */
  sqlite3_tokenizer_cursor *pCsr; /* Cursor to iterate through zInput */
  int iRowid;                     /* Current 'rowid' value */
  const char *zToken;             /* Current 'token' value */
  int nToken;                     /* Size of zToken in bytes */
  int iStart;                     /* Current 'start' value */
  int iEnd;                       /* Current 'end' value */
  int iPos;                       /* Current 'pos' value */
};

/*
** Query FTS for the tokenizer implementation named zName.
*/
static int fts3tokQueryTokenizer(
  Fts3Hash *pHash,
  const char *zName,
  const sqlite3_tokenizer_module **pp,
  char **pzErr
){
  sqlite3_tokenizer_module *p;
  int nName = (int)strlen(zName);

  p = (sqlite3_tokenizer_module *)sqlite3Fts3HashFind(pHash, zName, nName+1);
  if( !p ){
    *pzErr = sqlite3_mprintf("unknown tokenizer: %s", zName);
    return SQLITE_ERROR;
  }

  *pp = p;
  return SQLITE_OK;
}

/*
** The second argument, argv[], is an array of pointers to nul-terminated
** strings. This function makes a copy of the array and strings into a 
** single block of memory. It then dequotes any of the strings that appear
** to be quoted.
**
** If successful, output parameter *pazDequote is set to point at the
** array of dequoted strings and SQLITE_OK is returned. The caller is
** responsible for eventually calling sqlite3_free() to free the array
** in this case. Or, if an error occurs, an SQLite error code is returned.
** The final value of *pazDequote is undefined in this case.
*/
static int fts3tokDequoteArray(
  int argc,                       /* Number of elements in argv[] */
  const char * const *argv,       /* Input array */
  char ***pazDequote              /* Output array */
){
  int rc = SQLITE_OK;             /* Return code */
  if( argc==0 ){
    *pazDequote = 0;
  }else{
    int i;
    int nByte = 0;
    char **azDequote;

    for(i=0; i<argc; i++){
      nByte += (int)(strlen(argv[i]) + 1);
    }

    *pazDequote = azDequote = sqlite3_malloc(sizeof(char *)*argc + nByte);
    if( azDequote==0 ){
      rc = SQLITE_NOMEM;
    }else{
      char *pSpace = (char *)&azDequote[argc];
      for(i=0; i<argc; i++){
        int n = (int)strlen(argv[i]);
        azDequote[i] = pSpace;
        memcpy(pSpace, argv[i], n+1);
        sqlite3Fts3Dequote(pSpace);
        pSpace += (n+1);
      }
    }
  }

  return rc;
}

/*
** Schema of the tokenizer table.
*/
#define FTS3_TOK_SCHEMA "CREATE TABLE x(input, token, start, end, position)"

/*
** This function does all the work for both the xConnect and xCreate methods.
** These tables have no persistent representation of their own, so xConnect
** and xCreate are identical operations.
**
**   argv[0]: module name
**   argv[1]: database name 
**   argv[2]: table name
**   argv[3]: first argument (tokenizer name)
*/
static int fts3tokConnectMethod(
  sqlite3 *db,                    /* Database connection */
  void *pHash,                    /* Hash table of tokenizers */
  int argc,                       /* Number of elements in argv array */
  const char * const *argv,       /* xCreate/xConnect argument array */
  sqlite3_vtab **ppVtab,          /* OUT: New sqlite3_vtab object */
  char **pzErr                    /* OUT: sqlite3_malloc'd error message */
){
  Fts3tokTable *pTab;
  const sqlite3_tokenizer_module *pMod = 0;
  sqlite3_tokenizer *pTok = 0;
  int rc;
  char **azDequote = 0;
  int nDequote;

  rc = sqlite3_declare_vtab(db, FTS3_TOK_SCHEMA);
  if( rc!=SQLITE_OK ) return rc;

  nDequote = argc-3;
  rc = fts3tokDequoteArray(nDequote, &argv[3], &azDequote);

  if( rc==SQLITE_OK ){
    const char *zModule;
    if( nDequote<1 ){
      zModule = "simple";
    }else{
      zModule = azDequote[0];
    }
    rc = fts3tokQueryTokenizer((Fts3Hash*)pHash, zModule, &pMod, pzErr);
  }

  assert( (rc==SQLITE_OK)==(pMod!=0) );
  if( rc==SQLITE_OK ){
    const char * const *azArg = (const char * const *)&azDequote[1];
    rc = pMod->xCreate((nDequote>1 ? nDequote-1 : 0), azArg, &pTok);
  }

  if( rc==SQLITE_OK ){
    pTab = (Fts3tokTable *)sqlite3_malloc(sizeof(Fts3tokTable));
    if( pTab==0 ){
      rc = SQLITE_NOMEM;
    }
  }

  if( rc==SQLITE_OK ){
    memset(pTab, 0, sizeof(Fts3tokTable));
    pTab->pMod = pMod;
    pTab->pTok = pTok;
    *ppVtab = &pTab->base;
  }else{
    if( pTok ){
      pMod->xDestroy(pTok);
    }
  }

  sqlite3_free(azDequote);
  return rc;
}

/*
** This function does the work for both the xDisconnect and xDestroy methods.
** These tables have no persistent representation of their own, so xDisconnect
** and xDestroy are identical operations.
*/
static int fts3tokDisconnectMethod(sqlite3_vtab *pVtab){
  Fts3tokTable *pTab = (Fts3tokTable *)pVtab;

  pTab->pMod->xDestroy(pTab->pTok);
  sqlite3_free(pTab);
  return SQLITE_OK;
}

/*
** xBestIndex - Analyze a WHERE and ORDER BY clause.
*/
static int fts3tokBestIndexMethod(
  sqlite3_vtab *pVTab, 
  sqlite3_index_info *pInfo
){
  int i;
  UNUSED_PARAMETER(pVTab);

  for(i=0; i<pInfo->nConstraint; i++){
    if( pInfo->aConstraint[i].usable 
     && pInfo->aConstraint[i].iColumn==0 
     && pInfo->aConstraint[i].op==SQLITE_INDEX_CONSTRAINT_EQ 
    ){
      pInfo->idxNum = 1;
      pInfo->aConstraintUsage[i].argvIndex = 1;
      pInfo->aConstraintUsage[i].omit = 1;
      pInfo->estimatedCost = 1;
      return SQLITE_OK;
    }
  }

  pInfo->idxNum = 0;
  assert( pInfo->estimatedCost>1000000.0 );

  return SQLITE_OK;
}

/*
** xOpen - Open a cursor.
*/
static int fts3tokOpenMethod(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCsr){
  Fts3tokCursor *pCsr;
  UNUSED_PARAMETER(pVTab);

  pCsr = (Fts3tokCursor *)sqlite3_malloc(sizeof(Fts3tokCursor));
  if( pCsr==0 ){
    return SQLITE_NOMEM;
  }
  memset(pCsr, 0, sizeof(Fts3tokCursor));

  *ppCsr = (sqlite3_vtab_cursor *)pCsr;
  return SQLITE_OK;
}

/*
** Reset the tokenizer cursor passed as the only argument. As if it had
** just been returned by fts3tokOpenMethod().
*/
static void fts3tokResetCursor(Fts3tokCursor *pCsr){
  if( pCsr->pCsr ){
    Fts3tokTable *pTab = (Fts3tokTable *)(pCsr->base.pVtab);
    pTab->pMod->xClose(pCsr->pCsr);
    pCsr->pCsr = 0;
  }
  sqlite3_free(pCsr->zInput);
  pCsr->zInput = 0;
  pCsr->zToken = 0;
  pCsr->nToken = 0;
  pCsr->iStart = 0;
  pCsr->iEnd = 0;
  pCsr->iPos = 0;
  pCsr->iRowid = 0;
}

/*
** xClose - Close a cursor.
*/
static int fts3tokCloseMethod(sqlite3_vtab_cursor *pCursor){
  Fts3tokCursor *pCsr = (Fts3tokCursor *)pCursor;

  fts3tokResetCursor(pCsr);
  sqlite3_free(pCsr);
  return SQLITE_OK;
}

/*
** xNext - Advance the cursor to the next row, if any.
*/
static int fts3tokNextMethod(sqlite3_vtab_cursor *pCursor){
  Fts3tokCursor *pCsr = (Fts3tokCursor *)pCursor;
  Fts3tokTable *pTab = (Fts3tokTable *)(pCursor->pVtab);
  int rc;                         /* Return code */

  pCsr->iRowid++;
  rc = pTab->pMod->xNext(pCsr->pCsr,
      &pCsr->zToken, &pCsr->nToken,
      &pCsr->iStart, &pCsr->iEnd, &pCsr->iPos
  );

  if( rc!=SQLITE_OK ){
    fts3tokResetCursor(pCsr);
    if( rc==SQLITE_DONE ) rc = SQLITE_OK;
  }

  return rc;
}

/*
** xFilter - Initialize a cursor to point at the start of its data.
*/
static int fts3tokFilterMethod(
  sqlite3_vtab_cursor *pCursor,   /* The cursor used for this query */
  int idxNum,                     /* Strategy index */
  const char *idxStr,             /* Unused */
  int nVal,                       /* Number of elements in apVal */
  sqlite3_value **apVal           /* Arguments for the indexing scheme */
){
  int rc = SQLITE_ERROR;
  Fts3tokCursor *pCsr = (Fts3tokCursor *)pCursor;
  Fts3tokTable *pTab = (Fts3tokTable *)(pCursor->pVtab);
  UNUSED_PARAMETER(idxStr);
  UNUSED_PARAMETER(nVal);

  fts3tokResetCursor(pCsr);
  if( idxNum==1 ){
    const char *zByte = (const char *)sqlite3_value_text(apVal[0]);
    int nByte = sqlite3_value_bytes(apVal[0]);
    pCsr->zInput = sqlite3_malloc(nByte+1);
    if( pCsr->zInput==0 ){
      rc = SQLITE_NOMEM;
    }else{
      memcpy(pCsr->zInput, zByte, nByte);
      pCsr->zInput[nByte] = 0;
      rc = pTab->pMod->xOpen(pTab->pTok, pCsr->zInput, nByte, &pCsr->pCsr);
      if( rc==SQLITE_OK ){
        pCsr->pCsr->pTokenizer = pTab->pTok;
      }
    }
  }

  if( rc!=SQLITE_OK ) return rc;
  return fts3tokNextMethod(pCursor);
}

/*
** xEof - Return true if the cursor is at EOF, or false otherwise.
*/
static int fts3tokEofMethod(sqlite3_vtab_cursor *pCursor){
  Fts3tokCursor *pCsr = (Fts3tokCursor *)pCursor;
  return (pCsr->zToken==0);
}

/*
** xColumn - Return a column value.
*/
static int fts3tokColumnMethod(
  sqlite3_vtab_cursor *pCursor,   /* Cursor to retrieve value from */
  sqlite3_context *pCtx,          /* Context for sqlite3_result_xxx() calls */
  int iCol                        /* Index of column to read value from */
){
  Fts3tokCursor *pCsr = (Fts3tokCursor *)pCursor;

  /* CREATE TABLE x(input, token, start, end, position) */
  switch( iCol ){
    case 0:
      sqlite3_result_text(pCtx, pCsr->zInput, -1, SQLITE_TRANSIENT);
      break;
    case 1:
      sqlite3_result_text(pCtx, pCsr->zToken, pCsr->nToken, SQLITE_TRANSIENT);
      break;
    case 2:
      sqlite3_result_int(pCtx, pCsr->iStart);
      break;
    case 3:
      sqlite3_result_int(pCtx, pCsr->iEnd);
      break;
    default:
      assert( iCol==4 );
      sqlite3_result_int(pCtx, pCsr->iPos);
      break;
  }
  return SQLITE_OK;
}

/*
** xRowid - Return the current rowid for the cursor.
*/
static int fts3tokRowidMethod(
  sqlite3_vtab_cursor *pCursor,   /* Cursor to retrieve value from */
  sqlite_int64 *pRowid            /* OUT: Rowid value */
){
  Fts3tokCursor *pCsr = (Fts3tokCursor *)pCursor;
  *pRowid = (sqlite3_int64)pCsr->iRowid;
  return SQLITE_OK;
}

/*
** Register the fts3tok module with database connection db. Return SQLITE_OK
** if successful or an error code if sqlite3_create_module() fails.
*/
int sqlite3Fts3InitTok(sqlite3 *db, Fts3Hash *pHash){
  static const sqlite3_module fts3tok_module = {
     0,                           /* iVersion      */
     fts3tokConnectMethod,        /* xCreate       */
     fts3tokConnectMethod,        /* xConnect      */
     fts3tokBestIndexMethod,      /* xBestIndex    */
     fts3tokDisconnectMethod,     /* xDisconnect   */
     fts3tokDisconnectMethod,     /* xDestroy      */
     fts3tokOpenMethod,           /* xOpen         */
     fts3tokCloseMethod,          /* xClose        */
     fts3tokFilterMethod,         /* xFilter       */
     fts3tokNextMethod,           /* xNext         */
     fts3tokEofMethod,            /* xEof          */
     fts3tokColumnMethod,         /* xColumn       */
     fts3tokRowidMethod,          /* xRowid        */
     0,                           /* xUpdate       */
     0,                           /* xBegin        */
     0,                           /* xSync         */
     0,                           /* xCommit       */
     0,                           /* xRollback     */
     0,                           /* xFindFunction */
     0,                           /* xRename       */
     0,                           /* xSavepoint    */
     0,                           /* xRelease      */
     0                            /* xRollbackTo   */
  };
  int rc;                         /* Return code */

  rc = sqlite3_create_module(db, "fts3tokenize", &fts3tok_module, (void*)pHash);
  return rc;
}

#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */

}

#endif

/*
** Set up SQL objects in database db used to access the contents of
** the hash table pointed to by argument pHash. The hash table must
** been initialized to use string keys, and to take a private copy 
** of the key when a value is inserted. i.e. by a call similar to:
**
**    sqlite3Fts3HashInit(pHash, FTS3_HASH_STRING, 1);
**
** This function adds a scalar function (see header comment above
** scalarFunc() in this file for details) and, if ENABLE_TABLE is
** defined at compilation time, a temporary virtual table (see header 

  **
  ** then argc is set to 2, and the argv[] array contains pointers
  ** to the strings "arg1" and "arg2".
  **
  ** This method should return either SQLITE_OK (0), or an SQLite error 
  ** code. If SQLITE_OK is returned, then *ppTokenizer should be set
  ** to point at the newly created tokenizer structure. The generic
  ** sqlite3_tokenizer.pModule variable should not be initialized by
  ** this callback. The caller will do so.
  */
  int (*xCreate)(
    int argc,                           /* Size of argv array */
    const char *const*argv,             /* Tokenizer argument strings */
    sqlite3_tokenizer **ppTokenizer     /* OUT: Created tokenizer */
  );

** If so, no action is taken. Otherwise, the codepoint is added to the 
** unicode_tokenizer.aiException[] array. For the purposes of tokenization,
** the return value of sqlite3FtsUnicodeIsalnum() is inverted for all
** codepoints in the aiException[] array.
**
** If a standalone diacritic mark (one that sqlite3FtsUnicodeIsdiacritic()
** identifies as a diacritic) occurs in the zIn/nIn string it is ignored.
** It is not possible to change the behavior of the tokenizer with respect
** to these codepoints.
*/
static int unicodeAddExceptions(
  unicode_tokenizer *p,           /* Tokenizer to add exceptions to */
  int bAlnum,                     /* Replace Isalnum() return value with this */
  const char *zIn,                /* Array of characters to make exceptions */
  int nIn                         /* Length of z in bytes */

    ** size of the previous offset-list.
    */
    if( ppOffsetList ){
      *ppOffsetList = pReader->pOffsetList;
      *pnOffsetList = (int)(p - pReader->pOffsetList - 1);
    }

    /* List may have been edited in place by fts3EvalNearTrim() */
    while( p<pEnd && *p==0 ) p++;
  
    /* If there are no more entries in the doclist, set pOffsetList to
    ** NULL. Otherwise, set Fts3SegReader.iDocid to the next docid and
    ** Fts3SegReader.pOffsetList to point to the next offset list before
    ** returning.
    */

** When this function is called, buffer *ppList (size *pnList bytes) contains 
** a position list that may (or may not) feature multiple columns. This
** function adjusts the pointer *ppList and the length *pnList so that they
** identify the subset of the position list that corresponds to column iCol.
**
** If there are no entries in the input position list for column iCol, then
** *pnList is set to zero before returning.
**
** If parameter bZero is non-zero, then any part of the input list following
** the end of the output list is zeroed before returning.
*/
static void fts3ColumnFilter(
  int iCol,                       /* Column to filter on */
  int bZero,                      /* Zero out anything following *ppList */
  char **ppList,                  /* IN/OUT: Pointer to position list */
  int *pnList                     /* IN/OUT: Size of buffer *ppList in bytes */
){
  char *pList = *ppList;
  int nList = *pnList;
  char *pEnd = &pList[nList];
  int iCurrent = 0;

    if( nList==0 ){
      break;
    }
    p = &pList[1];
    p += sqlite3Fts3GetVarint32(p, &iCurrent);
  }

  if( bZero && &pList[nList]!=pEnd ){
    memset(&pList[nList], 0, pEnd - &pList[nList]);
  }
  *ppList = pList;
  *pnList = nList;
}

/*
** Cache data in the Fts3MultiSegReader.aBuffer[] buffer (overwriting any
** existing data). Grow the buffer if required.

        && apSegment[j]->iDocid==iDocid
      ){
        rc = fts3SegReaderNextDocid(p, apSegment[j], 0, 0);
        j++;
      }
      if( rc!=SQLITE_OK ) return rc;
      fts3SegReaderSort(pMsr->apSegment, nMerge, j, xCmp);

      if( nList>0 && fts3SegReaderIsPending(apSegment[0]) ){
        rc = fts3MsrBufferData(pMsr, pList, nList+1);
        if( rc!=SQLITE_OK ) return rc;
        assert( (pMsr->aBuffer[nList] & 0xFE)==0x00 );
        pList = pMsr->aBuffer;
      }

      if( pMsr->iColFilter>=0 ){
        fts3ColumnFilter(pMsr->iColFilter, 1, &pList, &nList);
      }

      if( nList>0 ){






          *paPoslist = pList;

        *piDocid = iDocid;
        *pnPoslist = nList;
        break;
      }
    }
  }

            && apSegment[j]->iDocid==iDocid
        ){
          fts3SegReaderNextDocid(p, apSegment[j], 0, 0);
          j++;
        }

        if( isColFilter ){
          fts3ColumnFilter(pFilter->iCol, 0, &pList, &nList);
        }

        if( !isIgnoreEmpty || nList>0 ){

          /* Calculate the 'docid' delta value to write into the merged 
          ** doclist. */
          sqlite3_int64 iDelta;

    comparision operator "REGEXP", based on the regular expression functions
    provided by the ICU library. The syntax of the operator is as described
    in SQLite documentation:

        <string> REGEXP <re-pattern>

    This extension uses the ICU defaults for regular expression matching
    behavior. Specifically, this means that:

        * Matching is case-sensitive,
        * Regular expression comments are not allowed within patterns, and
        * The '^' and '$' characters match the beginning and end of the
          <string> argument, not the beginning and end of lines within
          the <string> argument.

/*
** 2013-03-14
**
** 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.
**
*************************************************************************
**
** This file contains code for a demonstration virtual table that finds
** "approximate matches" - strings from a finite set that are nearly the
** same as a single input string.  The virtual table is called "amatch".
**
** A amatch virtual table is created like this:
**
**     CREATE VIRTUAL TABLE f USING approximate_match(
**        vocabulary_table=<tablename>,      -- V
**        vocabulary_word=<columnname>,      -- W
**        vocabulary_language=<columnname>,  -- L
**        edit_distances=<edit-cost-table>
**     );
**
** When it is created, the new amatch table must be supplied with the
** the name of a table V and columns V.W and V.L such that 
**
**     SELECT W FROM V WHERE L=$language
**
** returns the allowed vocabulary for the match.  If the "vocabulary_language"
** or L columnname is left unspecified or is an empty string, then no
** filtering of the vocabulary by language is performed. 
**
** For efficiency, it is essential that the vocabulary table be indexed:
**
**     CREATE vocab_index ON V(W)
**
** A separate edit-cost-table provides scoring information that defines 
** what it means for one string to be "close" to another.
**
** The edit-cost-table must contain exactly four columns (more precisely,
** the statement "SELECT * FROM <edit-cost-table>" must return records
** that consist of four columns). It does not matter what the columns are
** named. 
**
** Each row in the edit-cost-table represents a single character
** transformation going from user input to the vocabulary. The leftmost 
** column of the row (column 0) contains an integer identifier of the
** language to which the transformation rule belongs (see "MULTIPLE LANGUAGES"
** below). The second column of the row (column 1) contains the input
** character or characters - the characters of user input. The third 
** column contains characters as they appear in the vocabulary table.
** And the fourth column contains the integer cost of making the
** transformation. For example:
**
**    CREATE TABLE f_data(iLang, cFrom, cTo, Cost);
**    INSERT INTO f_data(iLang, cFrom, cTo, Cost) VALUES(0, '', 'a', 100);
**    INSERT INTO f_data(iLang, cFrom, cTo, Cost) VALUES(0, 'b', '', 87);
**    INSERT INTO f_data(iLang, cFrom, cTo, Cost) VALUES(0, 'o', 'oe', 38);
**    INSERT INTO f_data(iLang, cFrom, cTo, Cost) VALUES(0, 'oe', 'o', 40);
**
** The first row inserted into the edit-cost-table by the SQL script
** above indicates that the cost of having an extra 'a' in the vocabulary
** table that is missing in the user input 100.  (All costs are integers.
** Overall cost must not exceed 16777216.)  The second INSERT statement 
** creates a rule saying that the cost of having a single letter 'b' in
** user input which is missing in the vocabulary table is 87.  The third
** INSERT statement mean that the cost of matching an 'o' in user input 
** against an 'oe' in the vocabulary table is 38.  And so forth.
**
** The following rules are special:
**
**    INSERT INTO f_data(iLang, cFrom, cTo, Cost) VALUES(0, '?', '', 97);
**    INSERT INTO f_data(iLang, cFrom, cTo, Cost) VALUES(0, '', '?', 98);
**    INSERT INTO f_data(iLang, cFrom, cTo, Cost) VALUES(0, '?', '?', 99);
**
** The '?' to '' rule is the cost of having any single character in the input
** that is not found in the vocabular.  The '' to '?' rule is the cost of
** having a character in the vocabulary table that is missing from input.
** And the '?' to '?' rule is the cost of doing an arbitrary character
** substitution.  These three generic rules apply across all languages.
** In other words, the iLang field is ignored for the generic substitution
** rules.  If more than one cost is given for a generic substitution rule,
** then the lowest cost is used.
**
** Once it has been created, the amatch virtual table can be queried
** as follows:
**
**    SELECT word, distance FROM f
**     WHERE word MATCH 'abcdefg'
**       AND distance<200;
**
** This query outputs the strings contained in the T(F) field that
** are close to "abcdefg" and in order of increasing distance.  No string
** is output more than once.  If there are multiple ways to transform the
** target string ("abcdefg") into a string in the vocabulary table then
** the lowest cost transform is the one that is returned.  In this example,
** the search is limited to strings with a total distance of less than 200.
**
** For efficiency, it is important to put tight bounds on the distance.
** The time and memory space needed to perform this query is exponential
** in the maximum distance.  A good rule of thumb is to limit the distance
** to no more than 1.5 or 2 times the maximum cost of any rule in the
** edit-cost-table.
**
** The amatch is a read-only table.  Any attempt to DELETE, INSERT, or
** UPDATE on a amatch table will throw an error.
**
** It is important to put some kind of a limit on the amatch output.  This
** can be either in the form of a LIMIT clause at the end of the query,
** or better, a "distance<NNN" constraint where NNN is some number.  The
** running time and memory requirement is exponential in the value of NNN 
** so you want to make sure that NNN is not too big.  A value of NNN that
** is about twice the average transformation cost seems to give good results.
**
** The amatch table can be useful for tasks such as spelling correction.
** Suppose all allowed words are in table vocabulary(w).  Then one would create
** an amatch virtual table like this:
**
**   CREATE VIRTUAL TABLE ex1 USING amatch(
**       vocabtable=vocabulary,
**       vocabcolumn=w,
**       edit_distances=ec1
**   );
**
** Then given an input word $word, look up close spellings this way:
**
**   SELECT word, distance FROM ex1
**    WHERE word MATCH $word AND distance<200;
**
** MULTIPLE LANGUAGES
**
** Normally, the "iLang" value associated with all character transformations
** in the edit-cost-table is zero. However, if required, the amatch 
** virtual table allows multiple languages to be defined. Each query uses 
** only a single iLang value.   This allows, for example, a single 
** amatch table to support multiple languages.
**
** By default, only the rules with iLang=0 are used. To specify an 
** alternative language, a "language = ?" expression must be added to the
** WHERE clause of a SELECT, where ? is the integer identifier of the desired 
** language. For example:
**
**   SELECT word, distance FROM ex1
**    WHERE word MATCH $word
**      AND distance<=200
**      AND language=1 -- Specify use language 1 instead of 0
**
** If no "language = ?" constraint is specified in the WHERE clause, language
** 0 is used.
**
** LIMITS
**
** The maximum language number is 2147483647.  The maximum length of either
** of the strings in the second or third column of the amatch data table
** is 50 bytes.  The maximum cost on a rule is 1000.
*/
#include "sqlite3ext.h"
SQLITE_EXTENSION_INIT1
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <stdio.h>
#include <ctype.h>

/*
** Forward declaration of objects used by this implementation
*/
typedef struct amatch_vtab amatch_vtab;
typedef struct amatch_cursor amatch_cursor;
typedef struct amatch_rule amatch_rule;
typedef struct amatch_word amatch_word;
typedef struct amatch_avl amatch_avl;


/*****************************************************************************
** AVL Tree implementation
*/
/*
** Objects that want to be members of the AVL tree should embedded an
** instance of this structure.
*/
struct amatch_avl {
  amatch_word *pWord;   /* Points to the object being stored in the tree */
  char *zKey;           /* Key.  zero-terminated string.  Must be unique */
  amatch_avl *pBefore;  /* Other elements less than zKey */
  amatch_avl *pAfter;   /* Other elements greater than zKey */
  amatch_avl *pUp;      /* Parent element */
  short int height;     /* Height of this node.  Leaf==1 */
  short int imbalance;  /* Height difference between pBefore and pAfter */
};

/* Recompute the amatch_avl.height and amatch_avl.imbalance fields for p.
** Assume that the children of p have correct heights.
*/
static void amatchAvlRecomputeHeight(amatch_avl *p){
  short int hBefore = p->pBefore ? p->pBefore->height : 0;
  short int hAfter = p->pAfter ? p->pAfter->height : 0;
  p->imbalance = hBefore - hAfter;  /* -: pAfter higher.  +: pBefore higher */
  p->height = (hBefore>hAfter ? hBefore : hAfter)+1;
}

/*
**     P                B
**    / \              / \
**   B   Z    ==>     X   P
**  / \                  / \
** X   Y                Y   Z
**
*/
static amatch_avl *amatchAvlRotateBefore(amatch_avl *pP){
  amatch_avl *pB = pP->pBefore;
  amatch_avl *pY = pB->pAfter;
  pB->pUp = pP->pUp;
  pB->pAfter = pP;
  pP->pUp = pB;
  pP->pBefore = pY;
  if( pY ) pY->pUp = pP;
  amatchAvlRecomputeHeight(pP);
  amatchAvlRecomputeHeight(pB);
  return pB;
}

/*
**     P                A
**    / \              / \
**   X   A    ==>     P   Z
**      / \          / \
**     Y   Z        X   Y
**
*/
static amatch_avl *amatchAvlRotateAfter(amatch_avl *pP){
  amatch_avl *pA = pP->pAfter;
  amatch_avl *pY = pA->pBefore;
  pA->pUp = pP->pUp;
  pA->pBefore = pP;
  pP->pUp = pA;
  pP->pAfter = pY;
  if( pY ) pY->pUp = pP;
  amatchAvlRecomputeHeight(pP);
  amatchAvlRecomputeHeight(pA);
  return pA;
}

/*
** Return a pointer to the pBefore or pAfter pointer in the parent
** of p that points to p.  Or if p is the root node, return pp.
*/
static amatch_avl **amatchAvlFromPtr(amatch_avl *p, amatch_avl **pp){
  amatch_avl *pUp = p->pUp;
  if( pUp==0 ) return pp;
  if( pUp->pAfter==p ) return &pUp->pAfter;
  return &pUp->pBefore;
}

/*
** Rebalance all nodes starting with p and working up to the root.
** Return the new root.
*/
static amatch_avl *amatchAvlBalance(amatch_avl *p){
  amatch_avl *pTop = p;
  amatch_avl **pp;
  while( p ){
    amatchAvlRecomputeHeight(p);
    if( p->imbalance>=2 ){
      amatch_avl *pB = p->pBefore;
      if( pB->imbalance<0 ) p->pBefore = amatchAvlRotateAfter(pB);
      pp = amatchAvlFromPtr(p,&p);
      p = *pp = amatchAvlRotateBefore(p);
    }else if( p->imbalance<=(-2) ){
      amatch_avl *pA = p->pAfter;
      if( pA->imbalance>0 ) p->pAfter = amatchAvlRotateBefore(pA);
      pp = amatchAvlFromPtr(p,&p);
      p = *pp = amatchAvlRotateAfter(p);
    }
    pTop = p;
    p = p->pUp;
  }
  return pTop;
}

/* Search the tree rooted at p for an entry with zKey.  Return a pointer
** to the entry or return NULL.
*/
static amatch_avl *amatchAvlSearch(amatch_avl *p, const char *zKey){
  int c;
  while( p && (c = strcmp(zKey, p->zKey))!=0 ){
    p = (c<0) ? p->pBefore : p->pAfter;
  }
  return p;
}

/* Find the first node (the one with the smallest key).
*/
static amatch_avl *amatchAvlFirst(amatch_avl *p){
  if( p ) while( p->pBefore ) p = p->pBefore;
  return p;
}

#if 0 /* NOT USED */
/* Return the node with the next larger key after p.
*/
static amatch_avl *amatchAvlNext(amatch_avl *p){
  amatch_avl *pPrev = 0;
  while( p && p->pAfter==pPrev ){
    pPrev = p;
    p = p->pUp;
  }
  if( p && pPrev==0 ){
    p = amatchAvlFirst(p->pAfter);
  }
  return p;
}
#endif

#if 0 /* NOT USED */
/* Verify AVL tree integrity
*/
static int amatchAvlIntegrity(amatch_avl *pHead){
  amatch_avl *p;
  if( pHead==0 ) return 1;
  if( (p = pHead->pBefore)!=0 ){
    assert( p->pUp==pHead );
    assert( amatchAvlIntegrity(p) );
    assert( strcmp(p->zKey, pHead->zKey)<0 );
    while( p->pAfter ) p = p->pAfter;
    assert( strcmp(p->zKey, pHead->zKey)<0 );
  }
  if( (p = pHead->pAfter)!=0 ){
    assert( p->pUp==pHead );
    assert( amatchAvlIntegrity(p) );
    assert( strcmp(p->zKey, pHead->zKey)>0 );
    p = amatchAvlFirst(p);
    assert( strcmp(p->zKey, pHead->zKey)>0 );
  }
  return 1;
}
static int amatchAvlIntegrity2(amatch_avl *pHead){
  amatch_avl *p, *pNext;
  for(p=amatchAvlFirst(pHead); p; p=pNext){
    pNext = amatchAvlNext(p);
    if( pNext==0 ) break;
    assert( strcmp(p->zKey, pNext->zKey)<0 );
  }
  return 1;
}
#endif

/* Insert a new node pNew.  Return NULL on success.  If the key is not
** unique, then do not perform the insert but instead leave pNew unchanged
** and return a pointer to an existing node with the same key.
*/
static amatch_avl *amatchAvlInsert(amatch_avl **ppHead, amatch_avl *pNew){
  int c;
  amatch_avl *p = *ppHead;
  if( p==0 ){
    p = pNew;
    pNew->pUp = 0;
  }else{
    while( p ){
      c = strcmp(pNew->zKey, p->zKey);
      if( c<0 ){
        if( p->pBefore ){
          p = p->pBefore;
        }else{
          p->pBefore = pNew;
          pNew->pUp = p;
          break;
        }
      }else if( c>0 ){
        if( p->pAfter ){
          p = p->pAfter;
        }else{
          p->pAfter = pNew;
          pNew->pUp = p;
          break;
        }
      }else{
        return p;
      }
    }
  }
  pNew->pBefore = 0;
  pNew->pAfter = 0;
  pNew->height = 1;
  pNew->imbalance = 0;
  *ppHead = amatchAvlBalance(p);
  /* assert( amatchAvlIntegrity(*ppHead) ); */
  /* assert( amatchAvlIntegrity2(*ppHead) ); */
  return 0;
}

/* Remove node pOld from the tree.  pOld must be an element of the tree or
** the AVL tree will become corrupt.
*/
static void amatchAvlRemove(amatch_avl **ppHead, amatch_avl *pOld){
  amatch_avl **ppParent;
  amatch_avl *pBalance;
  /* assert( amatchAvlSearch(*ppHead, pOld->zKey)==pOld ); */
  ppParent = amatchAvlFromPtr(pOld, ppHead);
  if( pOld->pBefore==0 && pOld->pAfter==0 ){
    *ppParent = 0;
    pBalance = pOld->pUp;
  }else if( pOld->pBefore && pOld->pAfter ){
    amatch_avl *pX, *pY;
    pX = amatchAvlFirst(pOld->pAfter);
    *amatchAvlFromPtr(pX, 0) = pX->pAfter;
    if( pX->pAfter ) pX->pAfter->pUp = pX->pUp;
    pBalance = pX->pUp;
    pX->pAfter = pOld->pAfter;
    if( pX->pAfter ){
      pX->pAfter->pUp = pX;
    }else{
      assert( pBalance==pOld );
      pBalance = pX;
    }
    pX->pBefore = pY = pOld->pBefore;
    if( pY ) pY->pUp = pX;
    pX->pUp = pOld->pUp;
    *ppParent = pX;
  }else if( pOld->pBefore==0 ){
    *ppParent = pBalance = pOld->pAfter;
    pBalance->pUp = pOld->pUp;
  }else if( pOld->pAfter==0 ){
    *ppParent = pBalance = pOld->pBefore;
    pBalance->pUp = pOld->pUp;
  }
  *ppHead = amatchAvlBalance(pBalance);
  pOld->pUp = 0;
  pOld->pBefore = 0;
  pOld->pAfter = 0;
  /* assert( amatchAvlIntegrity(*ppHead) ); */
  /* assert( amatchAvlIntegrity2(*ppHead) ); */
}
/*
** End of the AVL Tree implementation
******************************************************************************/


/*
** Various types.
**
** amatch_cost is the "cost" of an edit operation.
**
** amatch_len is the length of a matching string.  
**
** amatch_langid is an ruleset identifier.
*/
typedef int amatch_cost;
typedef signed char amatch_len;
typedef int amatch_langid;

/*
** Limits
*/
#define AMATCH_MX_LENGTH          50  /* Maximum length of a rule string */
#define AMATCH_MX_LANGID  2147483647  /* Maximum rule ID */
#define AMATCH_MX_COST          1000  /* Maximum single-rule cost */

/*
** A match or partial match
*/
struct amatch_word {
  amatch_word *pNext;   /* Next on a list of all amatch_words */
  amatch_avl sCost;     /* Linkage of this node into the cost tree */
  amatch_avl sWord;     /* Linkage of this node into the word tree */
  amatch_cost rCost;    /* Cost of the match so far */
  int iSeq;             /* Sequence number */
  char zCost[10];       /* Cost key (text rendering of rCost) */
  short int nMatch;     /* Input characters matched */
  char zWord[4];        /* Text of the word.  Extra space appended as needed */
};

/*
** Each transformation rule is stored as an instance of this object.
** All rules are kept on a linked list sorted by rCost.
*/
struct amatch_rule {
  amatch_rule *pNext;      /* Next rule in order of increasing rCost */
  char *zFrom;             /* Transform from (a string from user input) */
  amatch_cost rCost;       /* Cost of this transformation */
  amatch_langid iLang;     /* The langauge to which this rule belongs */
  amatch_len nFrom, nTo;   /* Length of the zFrom and zTo strings */
  char zTo[4];             /* Tranform to V.W value (extra space appended) */
};

/* 
** A amatch virtual-table object 
*/
struct amatch_vtab {
  sqlite3_vtab base;         /* Base class - must be first */
  char *zClassName;          /* Name of this class.  Default: "amatch" */
  char *zDb;                 /* Name of database.  (ex: "main") */
  char *zSelf;               /* Name of this virtual table */
  char *zCostTab;            /* Name of edit-cost-table */
  char *zVocabTab;           /* Name of vocabulary table */
  char *zVocabWord;          /* Name of vocabulary table word column */
  char *zVocabLang;          /* Name of vocabulary table language column */
  amatch_rule *pRule;        /* All active rules in this amatch */
  amatch_cost rIns;          /* Generic insertion cost  '' -> ? */
  amatch_cost rDel;          /* Generic deletion cost  ? -> '' */
  amatch_cost rSub;          /* Generic substitution cost ? -> ? */
  sqlite3 *db;               /* The database connection */
  sqlite3_stmt *pVCheck;     /* Query to check zVocabTab */
  int nCursor;               /* Number of active cursors */
};

/* A amatch cursor object */
struct amatch_cursor {
  sqlite3_vtab_cursor base;  /* Base class - must be first */
  sqlite3_int64 iRowid;      /* The rowid of the current word */
  amatch_langid iLang;       /* Use this language ID */
  amatch_cost rLimit;        /* Maximum cost of any term */
  int nBuf;                  /* Space allocated for zBuf */
  int oomErr;                /* True following an OOM error */
  int nWord;                 /* Number of amatch_word objects */
  char *zBuf;                /* Temp-use buffer space */
  char *zInput;              /* Input word to match against */
  amatch_vtab *pVtab;        /* The virtual table this cursor belongs to */
  amatch_word *pAllWords;    /* List of all amatch_word objects */
  amatch_word *pCurrent;     /* Most recent solution */
  amatch_avl *pCost;         /* amatch_word objects keyed by iCost */
  amatch_avl *pWord;         /* amatch_word objects keyed by zWord */
};

/*
** The two input rule lists are both sorted in order of increasing
** cost.  Merge them together into a single list, sorted by cost, and
** return a pointer to the head of that list.
*/
static amatch_rule *amatchMergeRules(amatch_rule *pA, amatch_rule *pB){
  amatch_rule head;
  amatch_rule *pTail;

  pTail =  &head;
  while( pA && pB ){
    if( pA->rCost<=pB->rCost ){
      pTail->pNext = pA;
      pTail = pA;
      pA = pA->pNext;
    }else{
      pTail->pNext = pB;
      pTail = pB;
      pB = pB->pNext;
    }
  }
  if( pA==0 ){
    pTail->pNext = pB;
  }else{
    pTail->pNext = pA;
  }
  return head.pNext;
}

/*
** Statement pStmt currently points to a row in the amatch data table. This
** function allocates and populates a amatch_rule structure according to
** the content of the row.
**
** If successful, *ppRule is set to point to the new object and SQLITE_OK
** is returned. Otherwise, *ppRule is zeroed, *pzErr may be set to point
** to an error message and an SQLite error code returned.
*/
static int amatchLoadOneRule(
  amatch_vtab *p,                 /* Fuzzer virtual table handle */
  sqlite3_stmt *pStmt,            /* Base rule on statements current row */
  amatch_rule **ppRule,           /* OUT: New rule object */
  char **pzErr                    /* OUT: Error message */
){
  sqlite3_int64 iLang = sqlite3_column_int64(pStmt, 0);
  const char *zFrom = (const char *)sqlite3_column_text(pStmt, 1);
  const char *zTo = (const char *)sqlite3_column_text(pStmt, 2);
  amatch_cost rCost = sqlite3_column_int(pStmt, 3);

  int rc = SQLITE_OK;             /* Return code */
  int nFrom;                      /* Size of string zFrom, in bytes */
  int nTo;                        /* Size of string zTo, in bytes */
  amatch_rule *pRule = 0;         /* New rule object to return */

  if( zFrom==0 ) zFrom = "";
  if( zTo==0 ) zTo = "";
  nFrom = (int)strlen(zFrom);
  nTo = (int)strlen(zTo);

  /* Silently ignore null transformations */
  if( strcmp(zFrom, zTo)==0 ){
    if( zFrom[0]=='?' && zFrom[1]==0 ){
      if( p->rSub==0 || p->rSub>rCost ) p->rSub = rCost;
    }
    *ppRule = 0;
    return SQLITE_OK;
  }

  if( rCost<=0 || rCost>AMATCH_MX_COST ){
    *pzErr = sqlite3_mprintf("%s: cost must be between 1 and %d", 
        p->zClassName, AMATCH_MX_COST
    );
    rc = SQLITE_ERROR;
  }else
  if( nFrom>AMATCH_MX_LENGTH || nTo>AMATCH_MX_LENGTH ){
    *pzErr = sqlite3_mprintf("%s: maximum string length is %d", 
        p->zClassName, AMATCH_MX_LENGTH
    );
    rc = SQLITE_ERROR;    
  }else
  if( iLang<0 || iLang>AMATCH_MX_LANGID ){
    *pzErr = sqlite3_mprintf("%s: iLang must be between 0 and %d", 
        p->zClassName, AMATCH_MX_LANGID
    );
    rc = SQLITE_ERROR;    
  }else
  if( strcmp(zFrom,"")==0 && strcmp(zTo,"?")==0 ){
    if( p->rIns==0 || p->rIns>rCost ) p->rIns = rCost;
  }else
  if( strcmp(zFrom,"?")==0 && strcmp(zTo,"")==0 ){
    if( p->rDel==0 || p->rDel>rCost ) p->rDel = rCost;
  }else
  {
    pRule = sqlite3_malloc( sizeof(*pRule) + nFrom + nTo );
    if( pRule==0 ){
      rc = SQLITE_NOMEM;
    }else{
      memset(pRule, 0, sizeof(*pRule));
      pRule->zFrom = &pRule->zTo[nTo+1];
      pRule->nFrom = nFrom;
      memcpy(pRule->zFrom, zFrom, nFrom+1);
      memcpy(pRule->zTo, zTo, nTo+1);
      pRule->nTo = nTo;
      pRule->rCost = rCost;
      pRule->iLang = (int)iLang;
    }
  }

  *ppRule = pRule;
  return rc;
}

/*
** Free all the content in the edit-cost-table
*/
static void amatchFreeRules(amatch_vtab *p){
  while( p->pRule ){
    amatch_rule *pRule = p->pRule;
    p->pRule = pRule->pNext;
    sqlite3_free(pRule);
  }
  p->pRule = 0;
}

/*
** Load the content of the amatch data table into memory.
*/
static int amatchLoadRules(
  sqlite3 *db,                    /* Database handle */
  amatch_vtab *p,                 /* Virtual amatch table to configure */
  char **pzErr                    /* OUT: Error message */
){
  int rc = SQLITE_OK;             /* Return code */
  char *zSql;                     /* SELECT used to read from rules table */
  amatch_rule *pHead = 0;

  zSql = sqlite3_mprintf("SELECT * FROM %Q.%Q", p->zDb, p->zCostTab);
  if( zSql==0 ){
    rc = SQLITE_NOMEM;
  }else{
    int rc2;                      /* finalize() return code */
    sqlite3_stmt *pStmt = 0;
    rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0);
    if( rc!=SQLITE_OK ){
      *pzErr = sqlite3_mprintf("%s: %s", p->zClassName, sqlite3_errmsg(db));
    }else if( sqlite3_column_count(pStmt)!=4 ){
      *pzErr = sqlite3_mprintf("%s: %s has %d columns, expected 4",
          p->zClassName, p->zCostTab, sqlite3_column_count(pStmt)
      );
      rc = SQLITE_ERROR;
    }else{
      while( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pStmt) ){
        amatch_rule *pRule = 0;
        rc = amatchLoadOneRule(p, pStmt, &pRule, pzErr);
        if( pRule ){
          pRule->pNext = pHead;
          pHead = pRule;
        }
      }
    }
    rc2 = sqlite3_finalize(pStmt);
    if( rc==SQLITE_OK ) rc = rc2;
  }
  sqlite3_free(zSql);

  /* All rules are now in a singly linked list starting at pHead. This
  ** block sorts them by cost and then sets amatch_vtab.pRule to point to 
  ** point to the head of the sorted list.
  */
  if( rc==SQLITE_OK ){
    unsigned int i;
    amatch_rule *pX;
    amatch_rule *a[15];
    for(i=0; i<sizeof(a)/sizeof(a[0]); i++) a[i] = 0;
    while( (pX = pHead)!=0 ){
      pHead = pX->pNext;
      pX->pNext = 0;
      for(i=0; a[i] && i<sizeof(a)/sizeof(a[0])-1; i++){
        pX = amatchMergeRules(a[i], pX);
        a[i] = 0;
      }
      a[i] = amatchMergeRules(a[i], pX);
    }
    for(pX=a[0], i=1; i<sizeof(a)/sizeof(a[0]); i++){
      pX = amatchMergeRules(a[i], pX);
    }
    p->pRule = amatchMergeRules(p->pRule, pX);
  }else{
    /* An error has occurred. Setting p->pRule to point to the head of the
    ** allocated list ensures that the list will be cleaned up in this case.
    */
    assert( p->pRule==0 );
    p->pRule = pHead;
  }

  return rc;
}

/*
** This function converts an SQL quoted string into an unquoted string
** and returns a pointer to a buffer allocated using sqlite3_malloc() 
** containing the result. The caller should eventually free this buffer
** using sqlite3_free.
**
** Examples:
**
**     "abc"   becomes   abc
**     'xyz'   becomes   xyz
**     [pqr]   becomes   pqr
**     `mno`   becomes   mno
*/
static char *amatchDequote(const char *zIn){
  int nIn;                        /* Size of input string, in bytes */
  char *zOut;                     /* Output (dequoted) string */

  nIn = (int)strlen(zIn);
  zOut = sqlite3_malloc(nIn+1);
  if( zOut ){
    char q = zIn[0];              /* Quote character (if any ) */

    if( q!='[' && q!= '\'' && q!='"' && q!='`' ){
      memcpy(zOut, zIn, nIn+1);
    }else{
      int iOut = 0;               /* Index of next byte to write to output */
      int iIn;                    /* Index of next byte to read from input */

      if( q=='[' ) q = ']';
      for(iIn=1; iIn<nIn; iIn++){
        if( zIn[iIn]==q ) iIn++;
        zOut[iOut++] = zIn[iIn];
      }
    }
    assert( (int)strlen(zOut)<=nIn );
  }
  return zOut;
}

/*
** Deallocate the pVCheck prepared statement.
*/
static void amatchVCheckClear(amatch_vtab *p){
  if( p->pVCheck ){
    sqlite3_finalize(p->pVCheck);
    p->pVCheck = 0;
  }
}

/*
** Deallocate an amatch_vtab object
*/
static void amatchFree(amatch_vtab *p){
  if( p ){
    amatchFreeRules(p);
    amatchVCheckClear(p);
    sqlite3_free(p->zClassName);
    sqlite3_free(p->zDb);
    sqlite3_free(p->zCostTab);
    sqlite3_free(p->zVocabTab);
    sqlite3_free(p->zVocabWord);
    sqlite3_free(p->zVocabLang);
    memset(p, 0, sizeof(*p));
    sqlite3_free(p);
  }
}

/*
** xDisconnect/xDestroy method for the amatch module.
*/
static int amatchDisconnect(sqlite3_vtab *pVtab){
  amatch_vtab *p = (amatch_vtab*)pVtab;
  assert( p->nCursor==0 );
  amatchFree(p);
  return SQLITE_OK;
}

/*
** Check to see if the argument is of the form:
**
**       KEY = VALUE
**
** If it is, return a pointer to the first character of VALUE.
** If not, return NULL.  Spaces around the = are ignored.
*/
static const char *amatchValueOfKey(const char *zKey, const char *zStr){
  int nKey = (int)strlen(zKey);
  int nStr = (int)strlen(zStr);
  int i;
  if( nStr<nKey+1 ) return 0;
  if( memcmp(zStr, zKey, nKey)!=0 ) return 0;
  for(i=nKey; isspace(zStr[i]); i++){}
  if( zStr[i]!='=' ) return 0;
  i++;
  while( isspace(zStr[i]) ){ i++; }
  return zStr+i;
}

/*
** xConnect/xCreate method for the amatch module. Arguments are:
**
**   argv[0]    -> module name  ("approximate_match")
**   argv[1]    -> database name
**   argv[2]    -> table name
**   argv[3...] -> arguments
*/
static int amatchConnect(
  sqlite3 *db,
  void *pAux,
  int argc, const char *const*argv,
  sqlite3_vtab **ppVtab,
  char **pzErr
){
  int rc = SQLITE_OK;             /* Return code */
  amatch_vtab *pNew = 0;          /* New virtual table */
  const char *zModule = argv[0];
  const char *zDb = argv[1];
  const char *zVal;
  int i;

  (void)pAux;
  *ppVtab = 0;
  pNew = sqlite3_malloc( sizeof(*pNew) );
  if( pNew==0 ) return SQLITE_NOMEM;
  rc = SQLITE_NOMEM;
  memset(pNew, 0, sizeof(*pNew));
  pNew->db = db;
  pNew->zClassName = sqlite3_mprintf("%s", zModule);
  if( pNew->zClassName==0 ) goto amatchConnectError;
  pNew->zDb = sqlite3_mprintf("%s", zDb);
  if( pNew->zDb==0 ) goto amatchConnectError;
  pNew->zSelf = sqlite3_mprintf("%s", argv[2]);
  if( pNew->zSelf==0 ) goto amatchConnectError;
  for(i=3; i<argc; i++){
    zVal = amatchValueOfKey("vocabulary_table", argv[i]);
    if( zVal ){
      sqlite3_free(pNew->zVocabTab);
      pNew->zVocabTab = amatchDequote(zVal);
      if( pNew->zVocabTab==0 ) goto amatchConnectError;
      continue;
    }
    zVal = amatchValueOfKey("vocabulary_word", argv[i]);
    if( zVal ){
      sqlite3_free(pNew->zVocabWord);
      pNew->zVocabWord = amatchDequote(zVal);
      if( pNew->zVocabWord==0 ) goto amatchConnectError;
      continue;
    }
    zVal = amatchValueOfKey("vocabulary_language", argv[i]);
    if( zVal ){
      sqlite3_free(pNew->zVocabLang);
      pNew->zVocabLang = amatchDequote(zVal);
      if( pNew->zVocabLang==0 ) goto amatchConnectError;
      continue;
    }
    zVal = amatchValueOfKey("edit_distances", argv[i]);
    if( zVal ){
      sqlite3_free(pNew->zCostTab);
      pNew->zCostTab = amatchDequote(zVal);
      if( pNew->zCostTab==0 ) goto amatchConnectError;
      continue;
    }
    *pzErr = sqlite3_mprintf("unrecognized argument: [%s]\n", argv[i]);
    amatchFree(pNew);
    *ppVtab = 0;
    return SQLITE_ERROR;
  }
  rc = SQLITE_OK;
  if( pNew->zCostTab==0 ){
    *pzErr = sqlite3_mprintf("no edit_distances table specified");
    rc = SQLITE_ERROR;
  }else{
    rc = amatchLoadRules(db, pNew, pzErr);
  }
  if( rc==SQLITE_OK ){
    rc = sqlite3_declare_vtab(db,
           "CREATE TABLE x(word,distance,language,"
           "command HIDDEN,nword HIDDEN)"
         );
#define AMATCH_COL_WORD       0
#define AMATCH_COL_DISTANCE   1
#define AMATCH_COL_LANGUAGE   2
#define AMATCH_COL_COMMAND    3
#define AMATCH_COL_NWORD      4
  }
  if( rc!=SQLITE_OK ){
    amatchFree(pNew);
  }
  *ppVtab = &pNew->base;
  return rc;

amatchConnectError:
  amatchFree(pNew);
  return rc;
}

/*
** Open a new amatch cursor.
*/
static int amatchOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
  amatch_vtab *p = (amatch_vtab*)pVTab;
  amatch_cursor *pCur;
  pCur = sqlite3_malloc( sizeof(*pCur) );
  if( pCur==0 ) return SQLITE_NOMEM;
  memset(pCur, 0, sizeof(*pCur));
  pCur->pVtab = p;
  *ppCursor = &pCur->base;
  p->nCursor++;
  return SQLITE_OK;
}

/*
** Free up all the memory allocated by a cursor.  Set it rLimit to 0
** to indicate that it is at EOF.
*/
static void amatchClearCursor(amatch_cursor *pCur){
  amatch_word *pWord, *pNextWord;
  for(pWord=pCur->pAllWords; pWord; pWord=pNextWord){
    pNextWord = pWord->pNext;
    sqlite3_free(pWord);
  }
  pCur->pAllWords = 0;
  sqlite3_free(pCur->zInput);
  pCur->zInput = 0;
  pCur->pCost = 0;
  pCur->pWord = 0;
  pCur->pCurrent = 0;
  pCur->rLimit = 1000000;
  pCur->iLang = 0;
  pCur->nWord = 0;
}

/*
** Close a amatch cursor.
*/
static int amatchClose(sqlite3_vtab_cursor *cur){
  amatch_cursor *pCur = (amatch_cursor *)cur;
  amatchClearCursor(pCur);
  pCur->pVtab->nCursor--;
  sqlite3_free(pCur);
  return SQLITE_OK;
}

/*
** Render a 24-bit unsigned integer as a 4-byte base-64 number.
*/
static void amatchEncodeInt(int x, char *z){
  static const char a[] = 
    "0123456789"
    "ABCDEFGHIJ"
    "KLMNOPQRST"
    "UVWXYZ^abc"
    "defghijklm"
    "nopqrstuvw"
    "xyz~";
  z[0] = a[(x>>18)&0x3f];
  z[1] = a[(x>>12)&0x3f];
  z[2] = a[(x>>6)&0x3f];
  z[3] = a[x&0x3f];
}

/*
** Write the zCost[] field for a amatch_word object
*/
static void amatchWriteCost(amatch_word *pWord){
  amatchEncodeInt(pWord->rCost, pWord->zCost);
  amatchEncodeInt(pWord->iSeq, pWord->zCost+4);
  pWord->zCost[8] = 0;
}

/*
** Add a new amatch_word object to the queue.
**
** If a prior amatch_word object with the same zWord, and nMatch
** already exists, update its rCost (if the new rCost is less) but
** otherwise leave it unchanged.  Do not add a duplicate.
**
** Do nothing if the cost exceeds threshold.
*/
static void amatchAddWord(
  amatch_cursor *pCur,
  amatch_cost rCost,
  int nMatch,
  const char *zWordBase,
  const char *zWordTail
){
  amatch_word *pWord;
  amatch_avl *pNode;
  amatch_avl *pOther;
  int nBase, nTail;
  char zBuf[4];
  
  if( rCost>pCur->rLimit ){
    return;
  }
  nBase = (int)strlen(zWordBase);
  nTail = (int)strlen(zWordTail);
  if( nBase+nTail+3>pCur->nBuf ){
    pCur->nBuf = nBase+nTail+100;
    pCur->zBuf = sqlite3_realloc(pCur->zBuf, pCur->nBuf);
    if( pCur->zBuf==0 ){
      pCur->nBuf = 0;
      return;
    }
  }
  amatchEncodeInt(nMatch, zBuf);
  memcpy(pCur->zBuf, zBuf+2, 2);
  memcpy(pCur->zBuf+2, zWordBase, nBase);
  memcpy(pCur->zBuf+2+nBase, zWordTail, nTail+1);
  pNode = amatchAvlSearch(pCur->pWord, pCur->zBuf);
  if( pNode ){
    pWord = pNode->pWord;
    if( pWord->rCost>rCost ){
#ifdef AMATCH_TRACE_1
      printf("UPDATE [%s][%.*s^%s] %d (\"%s\" \"%s\")\n",
             pWord->zWord+2, pWord->nMatch, pCur->zInput, pCur->zInput,
             pWord->rCost, pWord->zWord, pWord->zCost);
#endif
      amatchAvlRemove(&pCur->pCost, &pWord->sCost);
      pWord->rCost = rCost;
      amatchWriteCost(pWord);
#ifdef AMATCH_TRACE_1
      printf("  ---> %d (\"%s\" \"%s\")\n",
             pWord->rCost, pWord->zWord, pWord->zCost);
#endif
      pOther = amatchAvlInsert(&pCur->pCost, &pWord->sCost);
      assert( pOther==0 ); (void)pOther;
    }
    return;
  }
  pWord = sqlite3_malloc( sizeof(*pWord) + nBase + nTail - 1 );
  if( pWord==0 ) return;
  memset(pWord, 0, sizeof(*pWord));
  pWord->rCost = rCost;
  pWord->iSeq = pCur->nWord++;
  amatchWriteCost(pWord);
  pWord->nMatch = nMatch;
  pWord->pNext = pCur->pAllWords;
  pCur->pAllWords = pWord;
  pWord->sCost.zKey = pWord->zCost;
  pWord->sCost.pWord = pWord;
  pOther = amatchAvlInsert(&pCur->pCost, &pWord->sCost);
  assert( pOther==0 ); (void)pOther;
  pWord->sWord.zKey = pWord->zWord;
  pWord->sWord.pWord = pWord;
  strcpy(pWord->zWord, pCur->zBuf);
  pOther = amatchAvlInsert(&pCur->pWord, &pWord->sWord);
  assert( pOther==0 ); (void)pOther;
#ifdef AMATCH_TRACE_1
  printf("INSERT [%s][%.*s^%s] %d (\"%s\" \"%s\")\n", pWord->zWord+2,
       pWord->nMatch, pCur->zInput, pCur->zInput+pWord->nMatch, rCost,
       pWord->zWord, pWord->zCost);
#endif
}

/*
** Advance a cursor to its next row of output
*/
static int amatchNext(sqlite3_vtab_cursor *cur){
  amatch_cursor *pCur = (amatch_cursor*)cur;
  amatch_word *pWord = 0;
  amatch_avl *pNode;
  int isMatch = 0;
  amatch_vtab *p = pCur->pVtab;
  int nWord;
  int rc;
  int i;
  const char *zW;
  amatch_rule *pRule;
  char *zBuf = 0;
  char nBuf = 0;
  char zNext[8];
  char zNextIn[8];
  int nNextIn;

  if( p->pVCheck==0 ){
    char *zSql;
    if( p->zVocabLang && p->zVocabLang[0] ){
      zSql = sqlite3_mprintf(
          "SELECT \"%s\" FROM \"%s\"",
          " WHERE \"%w\">=?1 AND \"%w\"=?2"
          " ORDER BY 1",
          p->zVocabWord, p->zVocabTab,
          p->zVocabWord, p->zVocabLang
      );
    }else{
      zSql = sqlite3_mprintf(
          "SELECT \"%s\" FROM \"%s\""
          " WHERE \"%w\">=?1"
          " ORDER BY 1",
          p->zVocabWord, p->zVocabTab,
          p->zVocabWord
      );
    }
    rc = sqlite3_prepare_v2(p->db, zSql, -1, &p->pVCheck, 0);
    sqlite3_free(zSql);
    if( rc ) return rc;
  }
  sqlite3_bind_int(p->pVCheck, 2, pCur->iLang);

  do{
    pNode = amatchAvlFirst(pCur->pCost);
    if( pNode==0 ){
      pWord = 0;
      break;
    }
    pWord = pNode->pWord;
    amatchAvlRemove(&pCur->pCost, &pWord->sCost);

#ifdef AMATCH_TRACE_1
    printf("PROCESS [%s][%.*s^%s] %d (\"%s\" \"%s\")\n",
       pWord->zWord+2, pWord->nMatch, pCur->zInput, pCur->zInput+pWord->nMatch,
       pWord->rCost, pWord->zWord, pWord->zCost);
#endif
    nWord = (int)strlen(pWord->zWord+2);
    if( nWord+20>nBuf ){
      nBuf = nWord+100;
      zBuf = sqlite3_realloc(zBuf, nBuf);
      if( zBuf==0 ) return SQLITE_NOMEM;
    }
    strcpy(zBuf, pWord->zWord+2);
    zNext[0] = 0;
    zNextIn[0] = pCur->zInput[pWord->nMatch];
    if( zNextIn[0] ){
      for(i=1; i<=4 && (pCur->zInput[pWord->nMatch+i]&0xc0)==0x80; i++){
        zNextIn[i] = pCur->zInput[pWord->nMatch+i];
      }
      zNextIn[i] = 0;
      nNextIn = i;
    }else{
      nNextIn = 0;
    }

    if( zNextIn[0] && zNextIn[0]!='*' ){
      sqlite3_reset(p->pVCheck);
      strcat(zBuf, zNextIn);
      sqlite3_bind_text(p->pVCheck, 1, zBuf, nWord+nNextIn, SQLITE_STATIC);
      rc = sqlite3_step(p->pVCheck);
      if( rc==SQLITE_ROW ){
        zW = (const char*)sqlite3_column_text(p->pVCheck, 0);
        if( strncmp(zBuf, zW, nWord+nNextIn)==0 ){
          amatchAddWord(pCur, pWord->rCost, pWord->nMatch+nNextIn, zBuf, "");
        }
      }
      zBuf[nWord] = 0;
    }

    while( 1 ){
      strcpy(zBuf+nWord, zNext);
      sqlite3_reset(p->pVCheck);
      sqlite3_bind_text(p->pVCheck, 1, zBuf, -1, SQLITE_TRANSIENT);
      rc = sqlite3_step(p->pVCheck);
      if( rc!=SQLITE_ROW ) break;
      zW = (const char*)sqlite3_column_text(p->pVCheck, 0);
      strcpy(zBuf+nWord, zNext);
      if( strncmp(zW, zBuf, nWord)!=0 ) break;
      if( (zNextIn[0]=='*' && zNextIn[1]==0)
       || (zNextIn[0]==0 && zW[nWord]==0)
      ){
        isMatch = 1;
        zNextIn[0] = 0;
        nNextIn = 0;
        break;
      }
      zNext[0] = zW[nWord];
      for(i=1; i<=4 && (zW[nWord+i]&0xc0)==0x80; i++){
        zNext[i] = zW[nWord+i];
      }
      zNext[i] = 0;
      zBuf[nWord] = 0;
      if( p->rIns>0 ){
        amatchAddWord(pCur, pWord->rCost+p->rIns, pWord->nMatch, 
                      zBuf, zNext);
      }
      if( p->rSub>0 ){
        amatchAddWord(pCur, pWord->rCost+p->rSub, pWord->nMatch+nNextIn, 
                      zBuf, zNext);
      }
      if( p->rIns<0 && p->rSub<0 ) break;
      zNext[i-1]++;  /* FIX ME */
    }
    sqlite3_reset(p->pVCheck);

    if( p->rDel>0 ){
      zBuf[nWord] = 0;
      amatchAddWord(pCur, pWord->rCost+p->rDel, pWord->nMatch+nNextIn,
                    zBuf, "");
    }

    for(pRule=p->pRule; pRule; pRule=pRule->pNext){
      if( pRule->iLang!=pCur->iLang ) continue;
      if( strncmp(pRule->zFrom, pCur->zInput+pWord->nMatch, pRule->nFrom)==0 ){
        amatchAddWord(pCur, pWord->rCost+pRule->rCost,
                      pWord->nMatch+pRule->nFrom, pWord->zWord+2, pRule->zTo);
      }
    }
  }while( !isMatch );
  pCur->pCurrent = pWord;
  sqlite3_free(zBuf);
  return SQLITE_OK;
}

/*
** Called to "rewind" a cursor back to the beginning so that
** it starts its output over again.  Always called at least once
** prior to any amatchColumn, amatchRowid, or amatchEof call.
*/
static int amatchFilter(
  sqlite3_vtab_cursor *pVtabCursor, 
  int idxNum, const char *idxStr,
  int argc, sqlite3_value **argv
){
  amatch_cursor *pCur = (amatch_cursor *)pVtabCursor;
  const char *zWord = "*";
  int idx;

  amatchClearCursor(pCur);
  idx = 0;
  if( idxNum & 1 ){
    zWord = (const char*)sqlite3_value_text(argv[0]);
    idx++;
  }
  if( idxNum & 2 ){
    pCur->rLimit = (amatch_cost)sqlite3_value_int(argv[idx]);
    idx++;
  }
  if( idxNum & 4 ){
    pCur->iLang = (amatch_cost)sqlite3_value_int(argv[idx]);
    idx++;
  }
  pCur->zInput = sqlite3_mprintf("%s", zWord);
  if( pCur->zInput==0 ) return SQLITE_NOMEM;
  amatchAddWord(pCur, 0, 0, "", "");
  amatchNext(pVtabCursor);

  return SQLITE_OK;
}

/*
** Only the word and distance columns have values.  All other columns
** return NULL
*/
static int amatchColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){
  amatch_cursor *pCur = (amatch_cursor*)cur;
  switch( i ){
    case AMATCH_COL_WORD: {
      sqlite3_result_text(ctx, pCur->pCurrent->zWord+2, -1, SQLITE_STATIC);
      break;
    }
    case AMATCH_COL_DISTANCE: {
      sqlite3_result_int(ctx, pCur->pCurrent->rCost);
      break;
    }
    case AMATCH_COL_LANGUAGE: {
      sqlite3_result_int(ctx, pCur->iLang);
      break;
    }
    case AMATCH_COL_NWORD: {
      sqlite3_result_int(ctx, pCur->nWord);
      break;
    }
    default: {
      sqlite3_result_null(ctx);
      break;
    }
  }
  return SQLITE_OK;
}

/*
** The rowid.
*/
static int amatchRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
  amatch_cursor *pCur = (amatch_cursor*)cur;
  *pRowid = pCur->iRowid;
  return SQLITE_OK;
}

/*
** EOF indicator
*/
static int amatchEof(sqlite3_vtab_cursor *cur){
  amatch_cursor *pCur = (amatch_cursor*)cur;
  return pCur->pCurrent==0;
}

/*
** Search for terms of these forms:
**
**   (A)    word MATCH $str
**   (B1)   distance < $value
**   (B2)   distance <= $value
**   (C)    language == $language
**
** The distance< and distance<= are both treated as distance<=.
** The query plan number is a bit vector:
**
**   bit 1:   Term of the form (A) found
**   bit 2:   Term like (B1) or (B2) found
**   bit 3:   Term like (C) found
**
** If bit-1 is set, $str is always in filter.argv[0].  If bit-2 is set
** then $value is in filter.argv[0] if bit-1 is clear and is in 
** filter.argv[1] if bit-1 is set.  If bit-3 is set, then $ruleid is
** in filter.argv[0] if bit-1 and bit-2 are both zero, is in
** filter.argv[1] if exactly one of bit-1 and bit-2 are set, and is in
** filter.argv[2] if both bit-1 and bit-2 are set.
*/
static int amatchBestIndex(
  sqlite3_vtab *tab,
  sqlite3_index_info *pIdxInfo
){
  int iPlan = 0;
  int iDistTerm = -1;
  int iLangTerm = -1;
  int i;
  const struct sqlite3_index_constraint *pConstraint;

  (void)tab;
  pConstraint = pIdxInfo->aConstraint;
  for(i=0; i<pIdxInfo->nConstraint; i++, pConstraint++){
    if( pConstraint->usable==0 ) continue;
    if( (iPlan & 1)==0 
     && pConstraint->iColumn==0
     && pConstraint->op==SQLITE_INDEX_CONSTRAINT_MATCH
    ){
      iPlan |= 1;
      pIdxInfo->aConstraintUsage[i].argvIndex = 1;
      pIdxInfo->aConstraintUsage[i].omit = 1;
    }
    if( (iPlan & 2)==0
     && pConstraint->iColumn==1
     && (pConstraint->op==SQLITE_INDEX_CONSTRAINT_LT
           || pConstraint->op==SQLITE_INDEX_CONSTRAINT_LE)
    ){
      iPlan |= 2;
      iDistTerm = i;
    }
    if( (iPlan & 4)==0
     && pConstraint->iColumn==2
     && pConstraint->op==SQLITE_INDEX_CONSTRAINT_EQ
    ){
      iPlan |= 4;
      pIdxInfo->aConstraintUsage[i].omit = 1;
      iLangTerm = i;
    }
  }
  if( iPlan & 2 ){
    pIdxInfo->aConstraintUsage[iDistTerm].argvIndex = 1+((iPlan&1)!=0);
  }
  if( iPlan & 4 ){
    int idx = 1;
    if( iPlan & 1 ) idx++;
    if( iPlan & 2 ) idx++;
    pIdxInfo->aConstraintUsage[iLangTerm].argvIndex = idx;
  }
  pIdxInfo->idxNum = iPlan;
  if( pIdxInfo->nOrderBy==1
   && pIdxInfo->aOrderBy[0].iColumn==1
   && pIdxInfo->aOrderBy[0].desc==0
  ){
    pIdxInfo->orderByConsumed = 1;
  }
  pIdxInfo->estimatedCost = (double)10000;
   
  return SQLITE_OK;
}

/*
** The xUpdate() method.  
**
** This implementation disallows DELETE and UPDATE.  The only thing
** allowed is INSERT into the "command" column.
*/
static int amatchUpdate(
  sqlite3_vtab *pVTab,
  int argc,
  sqlite3_value **argv,
  sqlite_int64 *pRowid
){
  amatch_vtab *p = (amatch_vtab*)pVTab;
  const unsigned char *zCmd;
  (void)pRowid;
  if( argc==1 ){
    pVTab->zErrMsg = sqlite3_mprintf("DELETE from %s is not allowed", 
                                      p->zSelf);
    return SQLITE_ERROR;
  }
  if( sqlite3_value_type(argv[0])!=SQLITE_NULL ){
    pVTab->zErrMsg = sqlite3_mprintf("UPDATE of %s is not allowed", 
                                      p->zSelf);
    return SQLITE_ERROR;
  }
  if( sqlite3_value_type(argv[2+AMATCH_COL_WORD])!=SQLITE_NULL
   || sqlite3_value_type(argv[2+AMATCH_COL_DISTANCE])!=SQLITE_NULL
   || sqlite3_value_type(argv[2+AMATCH_COL_LANGUAGE])!=SQLITE_NULL
  ){
    pVTab->zErrMsg = sqlite3_mprintf(
            "INSERT INTO %s allowed for column [command] only", p->zSelf);
    return SQLITE_ERROR;
  }
  zCmd = sqlite3_value_text(argv[2+AMATCH_COL_COMMAND]);
  if( zCmd==0 ) return SQLITE_OK;
  
  return SQLITE_OK;
}

/*
** A virtual table module that implements the "approximate_match".
*/
static sqlite3_module amatchModule = {
  0,                      /* iVersion */
  amatchConnect,          /* xCreate */
  amatchConnect,          /* xConnect */
  amatchBestIndex,        /* xBestIndex */
  amatchDisconnect,       /* xDisconnect */
  amatchDisconnect,       /* xDestroy */
  amatchOpen,             /* xOpen - open a cursor */
  amatchClose,            /* xClose - close a cursor */
  amatchFilter,           /* xFilter - configure scan constraints */
  amatchNext,             /* xNext - advance a cursor */
  amatchEof,              /* xEof - check for end of scan */
  amatchColumn,           /* xColumn - read data */
  amatchRowid,            /* xRowid - read data */
  amatchUpdate,           /* xUpdate */
  0,                      /* xBegin */
  0,                      /* xSync */
  0,                      /* xCommit */
  0,                      /* xRollback */
  0,                      /* xFindMethod */
  0,                      /* xRename */
  0,                      /* xSavepoint */
  0,                      /* xRelease */
  0                       /* xRollbackTo */
};

/*
** Register the amatch virtual table
*/
#ifdef _WIN32
__declspec(dllexport)
#endif
int sqlite3_amatch_init(
  sqlite3 *db, 
  char **pzErrMsg, 
  const sqlite3_api_routines *pApi
){
  int rc = SQLITE_OK;
  SQLITE_EXTENSION_INIT2(pApi);
  (void)pzErrMsg;  /* Not used */
  rc = sqlite3_create_module(db, "approximate_match", &amatchModule, 0);
  return rc;
}

/*
** 2013-04-16
**
** 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.
**
*************************************************************************
**
** This file contains code for a virtual table that finds the transitive
** closure of a parent/child relationship in a real table.  The virtual 
** table is called "transitive_closure".
**
** A transitive_closure virtual table is created like this:
**
**     CREATE VIRTUAL TABLE x USING transitive_closure(
**        tablename=<tablename>,      -- T
**        idcolumn=<columnname>,      -- X
**        parentcolumn=<columnname>   -- P
**     );
**
** When it is created, the new transitive_closure table may be supplied 
** with default values for the name of a table T and columns T.X and T.P.
** The T.X and T.P columns must contain integers.  The ideal case is for 
** T.X to be the INTEGER PRIMARY KEY.  The T.P column should reference
** the T.X column. The row referenced by T.P is the parent of the current row.
**
** The tablename, idcolumn, and parentcolumn supplied by the CREATE VIRTUAL
** TABLE statement may be overridden in individual queries by including
** terms like tablename='newtable', idcolumn='id2', or 
** parentcolumn='parent3' in the WHERE clause of the query.
**
** For efficiency, it is essential that there be an index on the P column:
**
**    CREATE Tidx1 ON T(P)
**
** Suppose a specific instance of the closure table is as follows:
**
**    CREATE VIRTUAL TABLE ct1 USING transitive_closure(
**       tablename='group',
**       idcolumn='groupId',
**       parentcolumn='parentId'
**    );
**
** Such an instance of the transitive_closure virtual table would be
** appropriate for walking a tree defined using a table like this, for example:
**
**    CREATE TABLE group(
**      groupId INTEGER PRIMARY KEY,
**      parentId INTEGER REFERENCES group
**    );
**    CREATE INDEX group_idx1 ON group(parentId);
**
** The group table above would presumably have other application-specific
** fields.  The key point here is that rows of the group table form a
** tree.  The purpose of the ct1 virtual table is to easily extract
** branches of that tree.
**
** Once it has been created, the ct1 virtual table can be queried
** as follows:
**
**    SELECT * FROM element
**     WHERE element.groupId IN (SELECT id FROM ct1 WHERE root=?1);
**
** The above query will return all elements that are part of group ?1
** or children of group ?1 or grand-children of ?1 and so forth for all
** descendents of group ?1.  The same query can be formulated as a join:
**
**    SELECT element.* FROM element, ct1
**     WHERE element.groupid=ct1.id
**       AND ct1.root=?1;
**
** The depth of the transitive_closure (the number of generations of
** parent/child relations to follow) can be limited by setting "depth"
** column in the WHERE clause.  So, for example, the following query
** finds only children and grandchildren but no further descendents:
**
**    SELECT element.* FROM element, ct1
**     WHERE element.groupid=ct1.id
**       AND ct1.root=?1
**       AND ct1.depth<=2;
**
** The "ct1.depth<=2" term could be a strict equality "ct1.depth=2" in
** order to find only the grandchildren of ?1, not ?1 itself or the
** children of ?1.
** 
** The root=?1 term must be supplied in WHERE clause or else the query
** of the ct1 virtual table will return an empty set.  The tablename,
** idcolumn, and parentcolumn attributes can be overridden in the WHERE
** clause if desired.  So, for example, the ct1 table could be repurposed
** to find ancestors rather than descendents by inverting the roles of
** the idcolumn and parentcolumn:
**
**    SELECT element.* FROM element, ct1
**     WHERE element.groupid=ct1.id
**       AND ct1.root=?1
**       AND ct1.idcolumn='parentId'
**       AND ct1.parentcolumn='groupId';
**
** Multiple calls to ct1 could be combined.  For example, the following
** query finds all elements that "cousins" of groupId ?1.  That is to say
** elements where the groupId is a grandchild of the grandparent of ?1.
** (This definition of "cousins" also includes siblings and self.)
**
**    SELECT element.* FROM element, ct1
**     WHERE element.groupId=ct1.id
**       AND ct1.depth=2
**       AND ct1.root IN (SELECT id FROM ct1
**                         WHERE root=?1
**                           AND depth=2
**                           AND idcolumn='parentId'
**                           AND parentcolumn='groupId');
**
** In our example, the group.groupId column is unique and thus the
** subquery will return exactly one row.  For that reason, the IN
** operator could be replaced by "=" to get the same result.  But
** in the general case where the idcolumn is not unique, an IN operator
** would be required for this kind of query.
**
** Note that because the tablename, idcolumn, and parentcolumn can
** all be specified in the query, it is possible for an application
** to define a single transitive_closure virtual table for use on lots
** of different hierarchy tables.  One might say:
**
**     CREATE VIRTUAL TABLE temp.closure USING transitive_closure;
**
** As each database connection is being opened.  Then the application
** would always have a "closure" virtual table handy to use for querying.
**
**    SELECT element.* FROM element, closure
**     WHERE element.groupid=ct1.id
**       AND closure.root=?1
**       AND closure.tablename='group'
**       AND closure.idname='groupId'
**       AND closure.parentname='parentId';
**
** See the documentation at http://www.sqlite.org/loadext.html for information
** on how to compile and use loadable extensions such as this one.
*/
#include "sqlite3ext.h"
SQLITE_EXTENSION_INIT1
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <stdio.h>
#include <ctype.h>

/*
** Forward declaration of objects used by this implementation
*/
typedef struct closure_vtab closure_vtab;
typedef struct closure_cursor closure_cursor;
typedef struct closure_queue closure_queue;
typedef struct closure_avl closure_avl;

/*****************************************************************************
** AVL Tree implementation
*/
/*
** Objects that want to be members of the AVL tree should embedded an
** instance of this structure.
*/
struct closure_avl {
  sqlite3_int64 id;     /* Id of this entry in the table */
  int iGeneration;      /* Which generation is this entry part of */
  closure_avl *pList;   /* A linked list of nodes */
  closure_avl *pBefore; /* Other elements less than id */
  closure_avl *pAfter;  /* Other elements greater than id */
  closure_avl *pUp;     /* Parent element */
  short int height;     /* Height of this node.  Leaf==1 */
  short int imbalance;  /* Height difference between pBefore and pAfter */
};

/* Recompute the closure_avl.height and closure_avl.imbalance fields for p.
** Assume that the children of p have correct heights.
*/
static void closureAvlRecomputeHeight(closure_avl *p){
  short int hBefore = p->pBefore ? p->pBefore->height : 0;
  short int hAfter = p->pAfter ? p->pAfter->height : 0;
  p->imbalance = hBefore - hAfter;  /* -: pAfter higher.  +: pBefore higher */
  p->height = (hBefore>hAfter ? hBefore : hAfter)+1;
}

/*
**     P                B
**    / \              / \
**   B   Z    ==>     X   P
**  / \                  / \
** X   Y                Y   Z
**
*/
static closure_avl *closureAvlRotateBefore(closure_avl *pP){
  closure_avl *pB = pP->pBefore;
  closure_avl *pY = pB->pAfter;
  pB->pUp = pP->pUp;
  pB->pAfter = pP;
  pP->pUp = pB;
  pP->pBefore = pY;
  if( pY ) pY->pUp = pP;
  closureAvlRecomputeHeight(pP);
  closureAvlRecomputeHeight(pB);
  return pB;
}

/*
**     P                A
**    / \              / \
**   X   A    ==>     P   Z
**      / \          / \
**     Y   Z        X   Y
**
*/
static closure_avl *closureAvlRotateAfter(closure_avl *pP){
  closure_avl *pA = pP->pAfter;
  closure_avl *pY = pA->pBefore;
  pA->pUp = pP->pUp;
  pA->pBefore = pP;
  pP->pUp = pA;
  pP->pAfter = pY;
  if( pY ) pY->pUp = pP;
  closureAvlRecomputeHeight(pP);
  closureAvlRecomputeHeight(pA);
  return pA;
}

/*
** Return a pointer to the pBefore or pAfter pointer in the parent
** of p that points to p.  Or if p is the root node, return pp.
*/
static closure_avl **closureAvlFromPtr(closure_avl *p, closure_avl **pp){
  closure_avl *pUp = p->pUp;
  if( pUp==0 ) return pp;
  if( pUp->pAfter==p ) return &pUp->pAfter;
  return &pUp->pBefore;
}

/*
** Rebalance all nodes starting with p and working up to the root.
** Return the new root.
*/
static closure_avl *closureAvlBalance(closure_avl *p){
  closure_avl *pTop = p;
  closure_avl **pp;
  while( p ){
    closureAvlRecomputeHeight(p);
    if( p->imbalance>=2 ){
      closure_avl *pB = p->pBefore;
      if( pB->imbalance<0 ) p->pBefore = closureAvlRotateAfter(pB);
      pp = closureAvlFromPtr(p,&p);
      p = *pp = closureAvlRotateBefore(p);
    }else if( p->imbalance<=(-2) ){
      closure_avl *pA = p->pAfter;
      if( pA->imbalance>0 ) p->pAfter = closureAvlRotateBefore(pA);
      pp = closureAvlFromPtr(p,&p);
      p = *pp = closureAvlRotateAfter(p);
    }
    pTop = p;
    p = p->pUp;
  }
  return pTop;
}

/* Search the tree rooted at p for an entry with id.  Return a pointer
** to the entry or return NULL.
*/
static closure_avl *closureAvlSearch(closure_avl *p, sqlite3_int64 id){
  while( p && id!=p->id ){
    p = (id<p->id) ? p->pBefore : p->pAfter;
  }
  return p;
}

/* Find the first node (the one with the smallest key).
*/
static closure_avl *closureAvlFirst(closure_avl *p){
  if( p ) while( p->pBefore ) p = p->pBefore;
  return p;
}

/* Return the node with the next larger key after p.
*/
closure_avl *closureAvlNext(closure_avl *p){
  closure_avl *pPrev = 0;
  while( p && p->pAfter==pPrev ){
    pPrev = p;
    p = p->pUp;
  }
  if( p && pPrev==0 ){
    p = closureAvlFirst(p->pAfter);
  }
  return p;
}
	
/* Insert a new node pNew.  Return NULL on success.  If the key is not
** unique, then do not perform the insert but instead leave pNew unchanged
** and return a pointer to an existing node with the same key.
*/
static closure_avl *closureAvlInsert(
  closure_avl **ppHead,  /* Head of the tree */
  closure_avl *pNew      /* New node to be inserted */
){
  closure_avl *p = *ppHead;
  if( p==0 ){
    p = pNew;
    pNew->pUp = 0;
  }else{
    while( p ){
      if( pNew->id<p->id ){
        if( p->pBefore ){
          p = p->pBefore;
        }else{
          p->pBefore = pNew;
          pNew->pUp = p;
          break;
        }
      }else if( pNew->id>p->id ){
        if( p->pAfter ){
          p = p->pAfter;
        }else{
          p->pAfter = pNew;
          pNew->pUp = p;
          break;
        }
      }else{
        return p;
      }
    }
  }
  pNew->pBefore = 0;
  pNew->pAfter = 0;
  pNew->height = 1;
  pNew->imbalance = 0;
  *ppHead = closureAvlBalance(p);
  return 0;
}

/* Walk the tree can call xDestroy on each node
*/
static void closureAvlDestroy(closure_avl *p, void (*xDestroy)(closure_avl*)){
  if( p ){
    closureAvlDestroy(p->pBefore, xDestroy);
    closureAvlDestroy(p->pAfter, xDestroy);
    xDestroy(p);
  }
}
/*
** End of the AVL Tree implementation
******************************************************************************/

/* 
** A closure virtual-table object 
*/
struct closure_vtab {
  sqlite3_vtab base;         /* Base class - must be first */
  char *zDb;                 /* Name of database.  (ex: "main") */
  char *zSelf;               /* Name of this virtual table */
  char *zTableName;          /* Name of table holding parent/child relation */
  char *zIdColumn;           /* Name of ID column of zTableName */
  char *zParentColumn;       /* Name of PARENT column in zTableName */
  sqlite3 *db;               /* The database connection */
  int nCursor;               /* Number of pending cursors */
};

/* A closure cursor object */
struct closure_cursor {
  sqlite3_vtab_cursor base;  /* Base class - must be first */
  closure_vtab *pVtab;       /* The virtual table this cursor belongs to */
  char *zTableName;          /* Name of table holding parent/child relation */
  char *zIdColumn;           /* Name of ID column of zTableName */
  char *zParentColumn;       /* Name of PARENT column in zTableName */
  closure_avl *pCurrent;     /* Current element of output */
  closure_avl *pClosure;     /* The complete closure tree */
};

/* A queue of AVL nodes */
struct closure_queue {
  closure_avl *pFirst;       /* Oldest node on the queue */
  closure_avl *pLast;        /* Youngest node on the queue */
};

/*
** Add a node to the end of the queue
*/
static void queuePush(closure_queue *pQueue, closure_avl *pNode){
  pNode->pList = 0;
  if( pQueue->pLast ){
    pQueue->pLast->pList = pNode;
  }else{
    pQueue->pFirst = pNode;
  }
  pQueue->pLast = pNode;
}

/*
** Extract the oldest element (the front element) from the queue.
*/
static closure_avl *queuePull(closure_queue *pQueue){
  closure_avl *p = pQueue->pFirst;
  if( p ){
    pQueue->pFirst = p->pList;
    if( pQueue->pFirst==0 ) pQueue->pLast = 0;
  }
  return p;
}

/*
** This function converts an SQL quoted string into an unquoted string
** and returns a pointer to a buffer allocated using sqlite3_malloc() 
** containing the result. The caller should eventually free this buffer
** using sqlite3_free.
**
** Examples:
**
**     "abc"   becomes   abc
**     'xyz'   becomes   xyz
**     [pqr]   becomes   pqr
**     `mno`   becomes   mno
*/
static char *closureDequote(const char *zIn){
  int nIn;                        /* Size of input string, in bytes */
  char *zOut;                     /* Output (dequoted) string */

  nIn = (int)strlen(zIn);
  zOut = sqlite3_malloc(nIn+1);
  if( zOut ){
    char q = zIn[0];              /* Quote character (if any ) */

    if( q!='[' && q!= '\'' && q!='"' && q!='`' ){
      memcpy(zOut, zIn, nIn+1);
    }else{
      int iOut = 0;               /* Index of next byte to write to output */
      int iIn;                    /* Index of next byte to read from input */

      if( q=='[' ) q = ']';
      for(iIn=1; iIn<nIn; iIn++){
        if( zIn[iIn]==q ) iIn++;
        zOut[iOut++] = zIn[iIn];
      }
    }
    assert( (int)strlen(zOut)<=nIn );
  }
  return zOut;
}

/*
** Deallocate an closure_vtab object
*/
static void closureFree(closure_vtab *p){
  if( p ){
    sqlite3_free(p->zDb);
    sqlite3_free(p->zSelf);
    sqlite3_free(p->zTableName);
    sqlite3_free(p->zIdColumn);
    sqlite3_free(p->zParentColumn);
    memset(p, 0, sizeof(*p));
    sqlite3_free(p);
  }
}

/*
** xDisconnect/xDestroy method for the closure module.
*/
static int closureDisconnect(sqlite3_vtab *pVtab){
  closure_vtab *p = (closure_vtab*)pVtab;
  assert( p->nCursor==0 );
  closureFree(p);
  return SQLITE_OK;
}

/*
** Check to see if the argument is of the form:
**
**       KEY = VALUE
**
** If it is, return a pointer to the first character of VALUE.
** If not, return NULL.  Spaces around the = are ignored.
*/
static const char *closureValueOfKey(const char *zKey, const char *zStr){
  int nKey = (int)strlen(zKey);
  int nStr = (int)strlen(zStr);
  int i;
  if( nStr<nKey+1 ) return 0;
  if( memcmp(zStr, zKey, nKey)!=0 ) return 0;
  for(i=nKey; isspace(zStr[i]); i++){}
  if( zStr[i]!='=' ) return 0;
  i++;
  while( isspace(zStr[i]) ){ i++; }
  return zStr+i;
}

/*
** xConnect/xCreate method for the closure module. Arguments are:
**
**   argv[0]    -> module name  ("approximate_match")
**   argv[1]    -> database name
**   argv[2]    -> table name
**   argv[3...] -> arguments
*/
static int closureConnect(
  sqlite3 *db,
  void *pAux,
  int argc, const char *const*argv,
  sqlite3_vtab **ppVtab,
  char **pzErr
){
  int rc = SQLITE_OK;              /* Return code */
  closure_vtab *pNew = 0;          /* New virtual table */
  const char *zDb = argv[1];
  const char *zVal;
  int i;

  (void)pAux;
  *ppVtab = 0;
  pNew = sqlite3_malloc( sizeof(*pNew) );
  if( pNew==0 ) return SQLITE_NOMEM;
  rc = SQLITE_NOMEM;
  memset(pNew, 0, sizeof(*pNew));
  pNew->db = db;
  pNew->zDb = sqlite3_mprintf("%s", zDb);
  if( pNew->zDb==0 ) goto closureConnectError;
  pNew->zSelf = sqlite3_mprintf("%s", argv[2]);
  if( pNew->zSelf==0 ) goto closureConnectError;
  for(i=3; i<argc; i++){
    zVal = closureValueOfKey("tablename", argv[i]);
    if( zVal ){
      sqlite3_free(pNew->zTableName);
      pNew->zTableName = closureDequote(zVal);
      if( pNew->zTableName==0 ) goto closureConnectError;
      continue;
    }
    zVal = closureValueOfKey("idcolumn", argv[i]);
    if( zVal ){
      sqlite3_free(pNew->zIdColumn);
      pNew->zIdColumn = closureDequote(zVal);
      if( pNew->zIdColumn==0 ) goto closureConnectError;
      continue;
    }
    zVal = closureValueOfKey("parentcolumn", argv[i]);
    if( zVal ){
      sqlite3_free(pNew->zParentColumn);
      pNew->zParentColumn = closureDequote(zVal);
      if( pNew->zParentColumn==0 ) goto closureConnectError;
      continue;
    }
    *pzErr = sqlite3_mprintf("unrecognized argument: [%s]\n", argv[i]);
    closureFree(pNew);
    *ppVtab = 0;
    return SQLITE_ERROR;
  }
  rc = sqlite3_declare_vtab(db,
         "CREATE TABLE x(id,depth,root HIDDEN,tablename HIDDEN,"
                        "idcolumn HIDDEN,parentcolumn HIDDEN)"
       );
#define CLOSURE_COL_ID              0
#define CLOSURE_COL_DEPTH           1
#define CLOSURE_COL_ROOT            2
#define CLOSURE_COL_TABLENAME       3
#define CLOSURE_COL_IDCOLUMN        4
#define CLOSURE_COL_PARENTCOLUMN    5
  if( rc!=SQLITE_OK ){
    closureFree(pNew);
  }
  *ppVtab = &pNew->base;
  return rc;

closureConnectError:
  closureFree(pNew);
  return rc;
}

/*
** Open a new closure cursor.
*/
static int closureOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
  closure_vtab *p = (closure_vtab*)pVTab;
  closure_cursor *pCur;
  pCur = sqlite3_malloc( sizeof(*pCur) );
  if( pCur==0 ) return SQLITE_NOMEM;
  memset(pCur, 0, sizeof(*pCur));
  pCur->pVtab = p;
  *ppCursor = &pCur->base;
  p->nCursor++;
  return SQLITE_OK;
}

/*
** Free up all the memory allocated by a cursor.  Set it rLimit to 0
** to indicate that it is at EOF.
*/
static void closureClearCursor(closure_cursor *pCur){
  closureAvlDestroy(pCur->pClosure, (void(*)(closure_avl*))sqlite3_free);
  sqlite3_free(pCur->zTableName);
  sqlite3_free(pCur->zIdColumn);
  sqlite3_free(pCur->zParentColumn);
  pCur->zTableName = 0;
  pCur->zIdColumn = 0;
  pCur->zParentColumn = 0;
  pCur->pCurrent = 0;
  pCur->pClosure = 0;
}

/*
** Close a closure cursor.
*/
static int closureClose(sqlite3_vtab_cursor *cur){
  closure_cursor *pCur = (closure_cursor *)cur;
  closureClearCursor(pCur);
  pCur->pVtab->nCursor--;
  sqlite3_free(pCur);
  return SQLITE_OK;
}

/*
** Advance a cursor to its next row of output
*/
static int closureNext(sqlite3_vtab_cursor *cur){
  closure_cursor *pCur = (closure_cursor*)cur;
  pCur->pCurrent = closureAvlNext(pCur->pCurrent);
  return SQLITE_OK;
}

/*
** Allocate and insert a node
*/
static int closureInsertNode(
  closure_queue *pQueue,  /* Add new node to this queue */
  closure_cursor *pCur,   /* The cursor into which to add the node */
  sqlite3_int64 id,       /* The node ID */
  int iGeneration         /* The generation number for this node */
){
  closure_avl *pNew = sqlite3_malloc( sizeof(*pNew) );
  if( pNew==0 ) return SQLITE_NOMEM;
  memset(pNew, 0, sizeof(*pNew));
  pNew->id = id;
  pNew->iGeneration = iGeneration;
  closureAvlInsert(&pCur->pClosure, pNew);
  queuePush(pQueue, pNew);
  return SQLITE_OK;
}

/*
** Called to "rewind" a cursor back to the beginning so that
** it starts its output over again.  Always called at least once
** prior to any closureColumn, closureRowid, or closureEof call.
**
** This routine actually computes the closure.
**
** See the comment at the beginning of closureBestIndex() for a 
** description of the meaning of idxNum.  The idxStr parameter is
** not used.
*/
static int closureFilter(
  sqlite3_vtab_cursor *pVtabCursor, 
  int idxNum, const char *idxStr,
  int argc, sqlite3_value **argv
){
  closure_cursor *pCur = (closure_cursor *)pVtabCursor;
  closure_vtab *pVtab = pCur->pVtab;
  sqlite3_int64 iRoot;
  int mxGen = 999999999;
  char *zSql;
  sqlite3_stmt *pStmt;
  closure_avl *pAvl;
  int rc = SQLITE_OK;
  const char *zTableName = pVtab->zTableName;
  const char *zIdColumn = pVtab->zIdColumn;
  const char *zParentColumn = pVtab->zParentColumn;
  closure_queue sQueue;

  (void)idxStr;  /* Unused parameter */
  (void)argc;    /* Unused parameter */
  closureClearCursor(pCur);
  memset(&sQueue, 0, sizeof(sQueue));
  if( (idxNum & 1)==0 ){
    /* No root=$root in the WHERE clause.  Return an empty set */
    return SQLITE_OK;
  }
  iRoot = sqlite3_value_int64(argv[0]);
  if( (idxNum & 0x000f0)!=0 ){
    mxGen = sqlite3_value_int(argv[(idxNum>>4)&0x0f]);
    if( (idxNum & 0x00002)!=0 ) mxGen--;
  }
  if( (idxNum & 0x00f00)!=0 ){
    zTableName = (const char*)sqlite3_value_text(argv[(idxNum>>8)&0x0f]);
    pCur->zTableName = sqlite3_mprintf("%s", zTableName);
  }
  if( (idxNum & 0x0f000)!=0 ){
    zIdColumn = (const char*)sqlite3_value_text(argv[(idxNum>>12)&0x0f]);
    pCur->zIdColumn = sqlite3_mprintf("%s", zIdColumn);
  }
  if( (idxNum & 0x0f0000)!=0 ){
    zParentColumn = (const char*)sqlite3_value_text(argv[(idxNum>>16)&0x0f]);
    pCur->zParentColumn = sqlite3_mprintf("%s", zParentColumn);
  }

  zSql = sqlite3_mprintf(
       "SELECT \"%w\".\"%w\" FROM \"%w\" WHERE \"%w\".\"%w\"=?1",
       zTableName, zIdColumn, zTableName, zTableName, zParentColumn);
  if( zSql==0 ){
    return SQLITE_NOMEM;
  }else{
    rc = sqlite3_prepare_v2(pVtab->db, zSql, -1, &pStmt, 0);
    sqlite3_free(zSql);
    if( rc ){
      sqlite3_free(pVtab->base.zErrMsg);
      pVtab->base.zErrMsg = sqlite3_mprintf("%s", sqlite3_errmsg(pVtab->db));
      return rc;
    }
  }
  if( rc==SQLITE_OK ){
    rc = closureInsertNode(&sQueue, pCur, iRoot, 0);
  }
  while( (pAvl = queuePull(&sQueue))!=0 ){
    if( pAvl->iGeneration>=mxGen ) continue;
    sqlite3_bind_int64(pStmt, 1, pAvl->id);
    while( rc==SQLITE_OK && sqlite3_step(pStmt)==SQLITE_ROW ){
      if( sqlite3_column_type(pStmt,0)==SQLITE_INTEGER ){
        sqlite3_int64 iNew = sqlite3_column_int64(pStmt, 0);
        if( closureAvlSearch(pCur->pClosure, iNew)==0 ){
          rc = closureInsertNode(&sQueue, pCur, iNew, pAvl->iGeneration+1);
        }
      }
    }
    sqlite3_reset(pStmt);
  }
  sqlite3_finalize(pStmt);
  if( rc==SQLITE_OK ){
    pCur->pCurrent = closureAvlFirst(pCur->pClosure);
  }

  return rc;
}

/*
** Only the word and distance columns have values.  All other columns
** return NULL
*/
static int closureColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){
  closure_cursor *pCur = (closure_cursor*)cur;
  switch( i ){
    case CLOSURE_COL_ID: {
      sqlite3_result_int64(ctx, pCur->pCurrent->id);
      break;
    }
    case CLOSURE_COL_DEPTH: {
      sqlite3_result_int(ctx, pCur->pCurrent->iGeneration);
      break;
    }
    case CLOSURE_COL_ROOT: {
      sqlite3_result_null(ctx);
      break;
    }
    case CLOSURE_COL_TABLENAME: {
      sqlite3_result_text(ctx,
         pCur->zTableName ? pCur->zTableName : pCur->pVtab->zTableName,
         -1, SQLITE_TRANSIENT);
      break;
    }
    case CLOSURE_COL_IDCOLUMN: {
      sqlite3_result_text(ctx,
         pCur->zIdColumn ? pCur->zIdColumn : pCur->pVtab->zIdColumn,
         -1, SQLITE_TRANSIENT);
      break;
    }
    case CLOSURE_COL_PARENTCOLUMN: {
      sqlite3_result_text(ctx,
         pCur->zParentColumn ? pCur->zParentColumn : pCur->pVtab->zParentColumn,
         -1, SQLITE_TRANSIENT);
      break;
    }
  }
  return SQLITE_OK;
}

/*
** The rowid.  For the closure table, this is the same as the "id" column.
*/
static int closureRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
  closure_cursor *pCur = (closure_cursor*)cur;
  *pRowid = pCur->pCurrent->id;
  return SQLITE_OK;
}

/*
** EOF indicator
*/
static int closureEof(sqlite3_vtab_cursor *cur){
  closure_cursor *pCur = (closure_cursor*)cur;
  return pCur->pCurrent==0;
}

/*
** Search for terms of these forms:
**
**   (A)    root = $root
**   (B1)   depth < $depth
**   (B2)   depth <= $depth
**   (B3)   depth = $depth
**   (C)    tablename = $tablename
**   (D)    idcolumn = $idcolumn
**   (E)    parentcolumn = $parentcolumn
**
** 
**
**   idxNum       meaning
**   ----------   ------------------------------------------------------
**   0x00000001   Term of the form (A) found
**   0x00000002   The term of bit-2 is like (B1)
**   0x000000f0   Index in filter.argv[] of $depth.  0 if not used.
**   0x00000f00   Index in filter.argv[] of $tablename.  0 if not used.
**   0x0000f000   Index in filter.argv[] of $idcolumn.  0 if not used
**   0x000f0000   Index in filter.argv[] of $parentcolumn.  0 if not used.
**
** There must be a term of type (A).  If there is not, then the index type
** is 0 and the query will return an empty set.
*/
static int closureBestIndex(
  sqlite3_vtab *pTab,             /* The virtual table */
  sqlite3_index_info *pIdxInfo    /* Information about the query */
){
  int iPlan = 0;
  int i;
  int idx = 1;
  const struct sqlite3_index_constraint *pConstraint;
  closure_vtab *pVtab = (closure_vtab*)pTab;

  pConstraint = pIdxInfo->aConstraint;
  for(i=0; i<pIdxInfo->nConstraint; i++, pConstraint++){
    if( pConstraint->usable==0 ) continue;
    if( (iPlan & 1)==0 
     && pConstraint->iColumn==CLOSURE_COL_ROOT
     && pConstraint->op==SQLITE_INDEX_CONSTRAINT_EQ
    ){
      iPlan |= 1;
      pIdxInfo->aConstraintUsage[i].argvIndex = 1;
      pIdxInfo->aConstraintUsage[i].omit = 1;
    }
    if( (iPlan & 0x0000f0)==0
     && pConstraint->iColumn==CLOSURE_COL_DEPTH
     && (pConstraint->op==SQLITE_INDEX_CONSTRAINT_LT
           || pConstraint->op==SQLITE_INDEX_CONSTRAINT_LE
           || pConstraint->op==SQLITE_INDEX_CONSTRAINT_EQ)
    ){
      iPlan |= idx<<4;
      pIdxInfo->aConstraintUsage[i].argvIndex = ++idx;
      if( pConstraint->op==SQLITE_INDEX_CONSTRAINT_LT ) iPlan |= 0x000002;
    }
    if( (iPlan & 0x000f00)==0
     && pConstraint->iColumn==CLOSURE_COL_TABLENAME
     && pConstraint->op==SQLITE_INDEX_CONSTRAINT_EQ
    ){
      iPlan |= idx<<8;
      pIdxInfo->aConstraintUsage[i].argvIndex = ++idx;
      pIdxInfo->aConstraintUsage[i].omit = 1;
    }
    if( (iPlan & 0x00f000)==0
     && pConstraint->iColumn==CLOSURE_COL_IDCOLUMN
     && pConstraint->op==SQLITE_INDEX_CONSTRAINT_EQ
    ){
      iPlan |= idx<<12;
      pIdxInfo->aConstraintUsage[i].argvIndex = ++idx;
      pIdxInfo->aConstraintUsage[i].omit = 1;
    }
    if( (iPlan & 0x0f0000)==0
     && pConstraint->iColumn==CLOSURE_COL_PARENTCOLUMN
     && pConstraint->op==SQLITE_INDEX_CONSTRAINT_EQ
    ){
      iPlan |= idx<<16;
      pIdxInfo->aConstraintUsage[i].argvIndex = ++idx;
      pIdxInfo->aConstraintUsage[i].omit = 1;
    }
  }
  if( (pVtab->zTableName==0    && (iPlan & 0x000f00)==0)
   || (pVtab->zIdColumn==0     && (iPlan & 0x00f000)==0)
   || (pVtab->zParentColumn==0 && (iPlan & 0x0f0000)==0)
  ){
    /* All of tablename, idcolumn, and parentcolumn must be specified
    ** in either the CREATE VIRTUAL TABLE or in the WHERE clause constraints
    ** or else the result is an empty set. */
    iPlan = 0;
  }
  pIdxInfo->idxNum = iPlan;
  if( pIdxInfo->nOrderBy==1
   && pIdxInfo->aOrderBy[0].iColumn==CLOSURE_COL_ID
   && pIdxInfo->aOrderBy[0].desc==0
  ){
    pIdxInfo->orderByConsumed = 1;
  }
  pIdxInfo->estimatedCost = (double)10000;
   
  return SQLITE_OK;
}

/*
** A virtual table module that implements the "approximate_match".
*/
static sqlite3_module closureModule = {
  0,                      /* iVersion */
  closureConnect,         /* xCreate */
  closureConnect,         /* xConnect */
  closureBestIndex,       /* xBestIndex */
  closureDisconnect,      /* xDisconnect */
  closureDisconnect,      /* xDestroy */
  closureOpen,            /* xOpen - open a cursor */
  closureClose,           /* xClose - close a cursor */
  closureFilter,          /* xFilter - configure scan constraints */
  closureNext,            /* xNext - advance a cursor */
  closureEof,             /* xEof - check for end of scan */
  closureColumn,          /* xColumn - read data */
  closureRowid,           /* xRowid - read data */
  0,                      /* xUpdate */
  0,                      /* xBegin */
  0,                      /* xSync */
  0,                      /* xCommit */
  0,                      /* xRollback */
  0,                      /* xFindMethod */
  0,                      /* xRename */
  0,                      /* xSavepoint */
  0,                      /* xRelease */
  0                       /* xRollbackTo */
};

/*
** Register the closure virtual table
*/
#ifdef _WIN32
__declspec(dllexport)
#endif
int sqlite3_closure_init(
  sqlite3 *db, 
  char **pzErrMsg, 
  const sqlite3_api_routines *pApi
){
  int rc = SQLITE_OK;
  SQLITE_EXTENSION_INIT2(pApi);
  (void)pzErrMsg;
  rc = sqlite3_create_module(db, "transitive_closure", &closureModule, 0);
  return rc;
}

**
** LIMITS
**
** The maximum ruleset number is 2147483647.  The maximum length of either
** of the strings in the second or third column of the fuzzer data table
** is 50 bytes.  The maximum cost on a rule is 1000.
*/
#include "sqlite3ext.h"
SQLITE_EXTENSION_INIT1

/* If SQLITE_DEBUG is not defined, disable assert statements. */
#if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
# define NDEBUG
#endif


#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <stdio.h>

#ifndef SQLITE_OMIT_VIRTUALTABLE

  0,                           /* xFindMethod */
  0,                           /* xRename */
};

#endif /* SQLITE_OMIT_VIRTUALTABLE */







#ifdef _WIN32

__declspec(dllexport)
#endif


int sqlite3_fuzzer_init(



  sqlite3 *db, 


  char **pzErrMsg, 




  const sqlite3_api_routines *pApi



){







  int rc = SQLITE_OK;

  SQLITE_EXTENSION_INIT2(pApi);
  rc = sqlite3_create_module(db, "fuzzer", &fuzzerModule, 0);
















  return rc;
}

/*
** 2013-04-17
**
** 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.
**
******************************************************************************
**
** This SQLite extension implements functions for the exact display
** and input of IEEE754 Binary64 floating-point numbers.
**
**   ieee754(X)
**   ieee754(Y,Z)
**
** In the first form, the value X should be a floating-point number.
** The function will return a string of the form 'ieee754(Y,Z)' where
** Y and Z are integers such that X==Y*pow(w.0,Z).
**
** In the second form, Y and Z are integers which are the mantissa and
** base-2 exponent of a new floating point number.  The function returns
** a floating-point value equal to Y*pow(2.0,Z).
**
** Examples:
**
**     ieee754(2.0)       ->     'ieee754(2,0)'
**     ieee754(45.25)     ->     'ieee754(181,-2)'
**     ieee754(2, 0)      ->     2.0
**     ieee754(181, -2)   ->     45.25
*/
#include "sqlite3ext.h"
SQLITE_EXTENSION_INIT1
#include <assert.h>
#include <string.h>

/*
** Implementation of the ieee754() function
*/
static void ieee754func(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  if( argc==1 ){
    sqlite3_int64 m, a;
    double r;
    int e;
    int isNeg;
    char zResult[100];
    assert( sizeof(m)==sizeof(r) );
    if( sqlite3_value_type(argv[0])!=SQLITE_FLOAT ) return;
    r = sqlite3_value_double(argv[0]);
    if( r<0.0 ){
      isNeg = 1;
      r = -r;
    }else{
      isNeg = 0;
    }
    memcpy(&a,&r,sizeof(a));
    if( a==0 ){
      e = 0;
      m = 0;
    }else{
      e = a>>52;
      m = a & ((((sqlite3_int64)1)<<52)-1);
      m |= ((sqlite3_int64)1)<<52;
      while( e<1075 && m>0 && (m&1)==0 ){
        m >>= 1;
        e++;
      }
      if( isNeg ) m = -m;
    }
    sqlite3_snprintf(sizeof(zResult), zResult, "ieee754(%lld,%d)",
                     m, e-1075);
    sqlite3_result_text(context, zResult, -1, SQLITE_TRANSIENT);
  }else if( argc==2 ){
    sqlite3_int64 m, e, a;
    double r;
    int isNeg = 0;
    m = sqlite3_value_int64(argv[0]);
    e = sqlite3_value_int64(argv[1]);
    if( m<0 ){
      isNeg = 1;
      m = -m;
      if( m<0 ) return;
    }else if( m==0 && e>1000 && e<1000 ){
      sqlite3_result_double(context, 0.0);
      return;
    }
    while( (m>>32)&0xffe00000 ){
      m >>= 1;
      e++;
    }
    while( ((m>>32)&0xfff00000)==0 ){
      m <<= 1;
      e--;
    }
    e += 1075;
    if( e<0 ) e = m = 0;
    if( e>0x7ff ) m = 0;
    a = m & ((((sqlite3_int64)1)<<52)-1);
    a |= e<<52;
    if( isNeg ) a |= ((sqlite3_int64)1)<<63;
    memcpy(&r, &a, sizeof(r));
    sqlite3_result_double(context, r);
  }
}


#ifdef _WIN32
__declspec(dllexport)
#endif
int sqlite3_ieee_init(
  sqlite3 *db, 
  char **pzErrMsg, 
  const sqlite3_api_routines *pApi
){
  int rc = SQLITE_OK;
  SQLITE_EXTENSION_INIT2(pApi);
  (void)pzErrMsg;  /* Unused parameter */
  rc = sqlite3_create_function(db, "ieee754", 1, SQLITE_UTF8, 0,
                               ieee754func, 0, 0);
  if( rc==SQLITE_OK ){
    rc = sqlite3_create_function(db, "ieee754", 2, SQLITE_UTF8, 0,
                                 ieee754func, 0, 0);
  }
  return rc;
}

/*
** 2013-02-28
**
** 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.
**
******************************************************************************
**
** This file contains code to implement the next_char(A,T,F,W) SQL function.
**
** The next_char(A,T,F,H) function finds all valid "next" characters for
** string A given the vocabulary in T.F.  The T.F field should be indexed.
** If the W value exists and is a non-empty string, then it is an SQL
** expression that limits the entries in T.F that will be considered.
**
** For example, suppose an application has a dictionary like this:
**
**   CREATE TABLE dictionary(word TEXT UNIQUE);
**
** Further suppose that for user keypad entry, it is desired to disable
** (gray out) keys that are not valid as the next character.  If the
** the user has previously entered (say) 'cha' then to find all allowed
** next characters (and thereby determine when keys should not be grayed
** out) run the following query:
**
**   SELECT next_char('cha','dictionary','word');
*/
#include "sqlite3ext.h"
SQLITE_EXTENSION_INIT1
#include <string.h>

/*
** A structure to hold context of the next_char() computation across
** nested function calls.
*/
typedef struct nextCharContext nextCharContext;
struct nextCharContext {
  sqlite3 *db;                      /* Database connection */
  sqlite3_stmt *pStmt;              /* Prepared statement used to query */
  const unsigned char *zPrefix;     /* Prefix to scan */
  int nPrefix;                      /* Size of zPrefix in bytes */
  int nAlloc;                       /* Space allocated to aResult */
  int nUsed;                        /* Space used in aResult */
  unsigned int *aResult;            /* Array of next characters */
  int mallocFailed;                 /* True if malloc fails */
  int otherError;                   /* True for any other failure */
};

/*
** Append a result character if the character is not already in the
** result.
*/
static void nextCharAppend(nextCharContext *p, unsigned c){
  int i;
  for(i=0; i<p->nUsed; i++){
    if( p->aResult[i]==c ) return;
  }
  if( p->nUsed+1 > p->nAlloc ){
    unsigned int *aNew;
    int n = p->nAlloc*2 + 30;
    aNew = sqlite3_realloc(p->aResult, n*sizeof(unsigned int));
    if( aNew==0 ){
      p->mallocFailed = 1;
      return;
    }else{
      p->aResult = aNew;
      p->nAlloc = n;
    }
  }
  p->aResult[p->nUsed++] = c;
}

/*
** Write a character into z[] as UTF8.  Return the number of bytes needed
** to hold the character
*/
static int writeUtf8(unsigned char *z, unsigned c){
  if( c<0x00080 ){
    z[0] = (unsigned char)(c&0xff);
    return 1;
  }
  if( c<0x00800 ){
    z[0] = 0xC0 + (unsigned char)((c>>6)&0x1F);
    z[1] = 0x80 + (unsigned char)(c & 0x3F);
    return 2;
  }
  if( c<0x10000 ){
    z[0] = 0xE0 + (unsigned char)((c>>12)&0x0F);
    z[1] = 0x80 + (unsigned char)((c>>6) & 0x3F);
    z[2] = 0x80 + (unsigned char)(c & 0x3F);
    return 3;
  }
  z[0] = 0xF0 + (unsigned char)((c>>18) & 0x07);
  z[1] = 0x80 + (unsigned char)((c>>12) & 0x3F);
  z[2] = 0x80 + (unsigned char)((c>>6) & 0x3F);
  z[3] = 0x80 + (unsigned char)(c & 0x3F);
  return 4;
}

/*
** Read a UTF8 character out of z[] and write it into *pOut.  Return
** the number of bytes in z[] that were used to construct the character.
*/
static int readUtf8(const unsigned char *z, unsigned *pOut){
  static const unsigned char validBits[] = {
    0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
    0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
    0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
    0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
    0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
    0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
    0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
    0x00, 0x01, 0x02, 0x03, 0x00, 0x01, 0x00, 0x00,
  };
  unsigned c = z[0];
  if( c<0xc0 ){
    *pOut = c;
    return 1;
  }else{
    int n = 1;
    c = validBits[c-0xc0];
    while( (z[n] & 0xc0)==0x80 ){
      c = (c<<6) + (0x3f & z[n++]);
    }
    if( c<0x80 || (c&0xFFFFF800)==0xD800 || (c&0xFFFFFFFE)==0xFFFE ){
      c = 0xFFFD;
    }
    *pOut = c;
    return n;
  }
}

/*
** The nextCharContext structure has been set up.  Add all "next" characters
** to the result set.
*/
static void findNextChars(nextCharContext *p){
  unsigned cPrev = 0;
  unsigned char zPrev[8];
  int n, rc;
  
  for(;;){
    sqlite3_bind_text(p->pStmt, 1, (char*)p->zPrefix, p->nPrefix,
                      SQLITE_STATIC);
    n = writeUtf8(zPrev, cPrev+1);
    sqlite3_bind_text(p->pStmt, 2, (char*)zPrev, n, SQLITE_STATIC);
    rc = sqlite3_step(p->pStmt);
    if( rc==SQLITE_DONE ){
      sqlite3_reset(p->pStmt);
      return;
    }else if( rc!=SQLITE_ROW ){
      p->otherError = rc;
      return;
    }else{
      const unsigned char *zOut = sqlite3_column_text(p->pStmt, 0);
      unsigned cNext;
      n = readUtf8(zOut+p->nPrefix, &cNext);
      sqlite3_reset(p->pStmt);
      nextCharAppend(p, cNext);
      cPrev = cNext;
      if( p->mallocFailed ) return;
    }
  }
}


/*
** next_character(A,T,F,W)
**
** Return a string composted of all next possible characters after
** A for elements of T.F.  If W is supplied, then it is an SQL expression
** that limits the elements in T.F that are considered.
*/
static void nextCharFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  nextCharContext c;
  const unsigned char *zTable = sqlite3_value_text(argv[1]);
  const unsigned char *zField = sqlite3_value_text(argv[2]);
  const unsigned char *zWhere;
  char *zSql;
  int rc;

  memset(&c, 0, sizeof(c));
  c.db = sqlite3_context_db_handle(context);
  c.zPrefix = sqlite3_value_text(argv[0]);
  c.nPrefix = sqlite3_value_bytes(argv[0]);
  if( zTable==0 || zField==0 || c.zPrefix==0 ) return;
  if( argc<4
   || (zWhere = sqlite3_value_text(argv[3]))==0
   || zWhere[0]==0
  ){
    zSql = sqlite3_mprintf(
        "SELECT \"%w\" FROM \"%w\""
        " WHERE \"%w\">=(?1 || ?2)"
        "   AND \"%w\"<=(?1 || char(1114111))" /* 1114111 == 0x10ffff */
        " ORDER BY 1 ASC LIMIT 1",
        zField, zTable, zField, zField);
  }else{
    zSql = sqlite3_mprintf(
        "SELECT \"%w\" FROM \"%w\""
        " WHERE \"%w\">=(?1 || ?2)"
        "   AND \"%w\"<=(?1 || char(1114111))" /* 1114111 == 0x10ffff */
        "   AND (%s)"
        " ORDER BY 1 ASC LIMIT 1",
        zField, zTable, zField, zField, zWhere);
  }
  if( zSql==0 ){
    sqlite3_result_error_nomem(context);
    return;
  }

  rc = sqlite3_prepare_v2(c.db, zSql, -1, &c.pStmt, 0);
  sqlite3_free(zSql);
  if( rc ){
    sqlite3_result_error(context, sqlite3_errmsg(c.db), -1);
    return;
  }
  findNextChars(&c);
  if( c.mallocFailed ){
    sqlite3_result_error_nomem(context);
  }else{
    unsigned char *pRes;
    pRes = sqlite3_malloc( c.nUsed*4 + 1 );
    if( pRes==0 ){
      sqlite3_result_error_nomem(context);
    }else{
      int i;
      int n = 0;
      for(i=0; i<c.nUsed; i++){
        n += writeUtf8(pRes+n, c.aResult[i]);
      }
      pRes[n] = 0;
      sqlite3_result_text(context, (const char*)pRes, n, sqlite3_free);
    }
  }
  sqlite3_finalize(c.pStmt);
  sqlite3_free(c.aResult);
}

#ifdef _WIN32
__declspec(dllexport)
#endif
int sqlite3_nextchar_init(
  sqlite3 *db, 
  char **pzErrMsg, 
  const sqlite3_api_routines *pApi
){
  int rc = SQLITE_OK;
  SQLITE_EXTENSION_INIT2(pApi);
  (void)pzErrMsg;  /* Unused parameter */
  rc = sqlite3_create_function(db, "next_char", 3, SQLITE_UTF8, 0,
                               nextCharFunc, 0, 0);
  if( rc==SQLITE_OK ){
    rc = sqlite3_create_function(db, "next_char", 4, SQLITE_UTF8, 0,
                                 nextCharFunc, 0, 0);
  }
  return rc;
}

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
******************************************************************************
**
** The code in this file implements a compact but reasonably
** efficient regular-expression matcher for posix extended regular
** expressions against UTF8 text.
**
** This file is an SQLite extension.  It registers a single function
** named "regexp(A,B)" where A is the regular expression and B is the
** string to be matched.  By registering this function, SQLite will also
** then implement the "B regexp A" operator.  Note that with the function
** the regular expression comes first, but with the operator it comes
** second.
**
**  The following regular expression syntax is supported:
**
**     X*      zero or more occurrences of X
**     X+      one or more occurrences of X
**     X?      zero or one occurrences of X
**     X{p,q}  between p and q occurrences of X
**     (X)     match X
**     X|Y     X or Y

** exhibits exponential behavior.  Note that the X{p,q} operator expands
** to p copies of X following by q-p copies of X? and that the size of the
** regular expression in the O(N*M) performance bound is computed after
** this expansion.
*/
#include <string.h>
#include <stdlib.h>
#include "sqlite3ext.h"
SQLITE_EXTENSION_INIT1

/*
** The following #defines change the names of some functions implemented in
** this file to prevent name collisions with C-library functions of the
** same name.
*/
#define re_match   sqlite3re_match
#define re_compile sqlite3re_compile
#define re_free    sqlite3re_free

/* The end-of-input character */
#define RE_EOF            0    /* End of input */

/* The NFA is implemented as sequence of opcodes taken from the following
** set.  Each opcode has a single integer argument.
*/

static int re_space_char(int c){
  return c==' ' || c=='\t' || c=='\n' || c=='\r' || c=='\v' || c=='\f';
}

/* Run a compiled regular expression on the zero-terminated input
** string zIn[].  Return true on a match and false if there is no match.
*/
static int re_match(ReCompiled *pRe, const unsigned char *zIn, int nIn){
  ReStateSet aStateSet[2], *pThis, *pNext;
  ReStateNumber aSpace[100];
  ReStateNumber *pToFree;
  unsigned int i = 0;
  unsigned int iSwap = 0;
  int c = RE_EOF+1;
  int cPrev = 0;
  int rc = 0;
  ReInput in;

  in.z = zIn;
  in.i = 0;
  in.mx = nIn>=0 ? nIn : (int)strlen((char const*)zIn);

  /* Look for the initial prefix match, if there is one. */
  if( pRe->nInit ){
    unsigned char x = pRe->zInit[0];
    while( in.i+pRe->nInit<=in.mx 
     && (zIn[in.i]!=x ||
         strncmp((const char*)zIn+in.i, (const char*)pRe->zInit, pRe->nInit)!=0)

  if( zIn[0]=='^' ){
    zIn++;
  }else{
    re_append(pRe, RE_OP_ANYSTAR, 0);
  }
  pRe->sIn.z = (unsigned char*)zIn;
  pRe->sIn.i = 0;
  pRe->sIn.mx = (int)strlen(zIn);
  zErr = re_subcompile_re(pRe);
  if( zErr ){
    re_free(pRe);
    return zErr;
  }
  if( rePeek(pRe)=='$' && pRe->sIn.i+1>=pRe->sIn.mx ){
    re_append(pRe, RE_OP_MATCH, RE_EOF);

  zStr = (const unsigned char*)sqlite3_value_text(argv[1]);
  if( zStr!=0 ){
    sqlite3_result_int(context, re_match(pRe, zStr, -1));
  }
}

/*
** Invoke this routine to register the regexp() function with the
** SQLite database connection.







*/







#ifdef _WIN32
__declspec(dllexport)

#endif


int sqlite3_regexp_init(

  sqlite3 *db, 
  char **pzErrMsg, 

  const sqlite3_api_routines *pApi

){







  int rc = SQLITE_OK;

  SQLITE_EXTENSION_INIT2(pApi);



  rc = sqlite3_create_function(db, "regexp", 2, SQLITE_UTF8, 0,
                                 re_sql_func, 0, 0);
  return rc;
}

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This module implements the spellfix1 VIRTUAL TABLE that can be used
** to search a large vocabulary for close matches.  See separate
** documentation (http://www.sqlite.org/spellfix1.html) for details.
*/

#include "sqlite3ext.h"
SQLITE_EXTENSION_INIT1

#ifndef SQLITE_AMALGAMATION
# include <string.h>
# include <stdio.h>
# include <stdlib.h>

# include <assert.h>
# define ALWAYS(X)  1
# define NEVER(X)   0
  typedef unsigned char u8;
  typedef unsigned short u16;


#include <ctype.h>
#endif

/*
** Character classes for ASCII characters:
**
**   0   ''        Silent letters:   H W
**   1   'A'       Any vowel:   A E I O U (Y)
**   2   'B'       A bilabeal stop or fricative:  B F P V W

  for(i=0; i<sizeof(translit)/sizeof(translit[0])-1; i++){
    assert( translit[i].cFrom<translit[i+1].cFrom );
  }

  return rc;
}












/*
** Extension load function.
*/
#ifdef _WIN32
__declspec(dllexport)
#endif
int sqlite3_spellfix_init(
  sqlite3 *db, 
  char **pzErrMsg, 
  const sqlite3_api_routines *pApi
){
  SQLITE_EXTENSION_INIT2(pApi);
  return spellfix1Register(db);
}

**     CREATE VIRTUAL TABLE nums USING wholenumber;
**     SELECT value FROM nums WHERE value<10;
**
** Results in:
**
**     1 2 3 4 5 6 7 8 9
*/
#include "sqlite3ext.h"
SQLITE_EXTENSION_INIT1
#include <assert.h>
#include <string.h>

#ifndef SQLITE_OMIT_VIRTUALTABLE


/* A wholenumber cursor object */

    pIdxInfo->aConstraintUsage[gtIdx].omit = 1;
  }
  if( pIdxInfo->nOrderBy==1
   && pIdxInfo->aOrderBy[0].desc==0
  ){
    pIdxInfo->orderByConsumed = 1;
  }
  if( (idxNum & 12)==0 ){
    pIdxInfo->estimatedCost = (double)100000000;
  }else if( (idxNum & 3)==0 ){
    pIdxInfo->estimatedCost = (double)5;
  }else{
  pIdxInfo->estimatedCost = (double)1;
  }
  return SQLITE_OK;
}

/*
** A virtual table module that provides read-only access to a
** Tcl global variable namespace.
*/

  0,                         /* xRollback */
  0,                         /* xFindMethod */
  0,                         /* xRename */
};

#endif /* SQLITE_OMIT_VIRTUALTABLE */

#ifdef _WIN32

__declspec(dllexport)
#endif
int sqlite3_wholenumber_init(

  sqlite3 *db, 
  char **pzErrMsg, 
  const sqlite3_api_routines *pApi
){
  int rc = SQLITE_OK;
  SQLITE_EXTENSION_INIT2(pApi);
#ifndef SQLITE_OMIT_VIRTUALTABLE
  rc = sqlite3_create_module(db, "wholenumber", &wholenumberModule, 0);
#endif
  return rc;
}

static int rtreeDeleteRowid(Rtree *pRtree, sqlite3_int64 iDelete){
  int rc;                         /* Return code */
  RtreeNode *pLeaf = 0;           /* Leaf node containing record iDelete */
  int iCell;                      /* Index of iDelete cell in pLeaf */
  RtreeNode *pRoot;               /* Root node of rtree structure */


  /* Obtain a reference to the root node to initialize Rtree.iDepth */
  rc = nodeAcquire(pRtree, 1, 0, &pRoot);

  /* Obtain a reference to the leaf node that contains the entry 
  ** about to be deleted. 
  */
  if( rc==SQLITE_OK ){
    rc = findLeafNode(pRtree, iDelete, &pLeaf);

#

if {![info exists testdir]} {
  set testdir [file join [file dirname [info script]] .. .. test]
}
source [file join [file dirname [info script]] rtree_util.tcl]
source $testdir/tester.tcl
set testprefix rtree1

# Test plan:
#
#   rtree-1.*: Creating/destroying r-tree tables.
#   rtree-2.*: Test the implicit constraints - unique rowid and
#              (coord[N]<=coord[N+1]) for even values of N. Also
#              automatic assigning of rowid values.

do_test rtree5-1.9 { 
  execsql { SELECT count(*) FROM t1 WHERE x1==5.0 }
} {1}

do_test rtree5-1.10 { 
  execsql { SELECT (1<<31)-5, (1<<31)-1, -1*(1<<31), -1*(1<<31)+5 }
} {2147483643 2147483647 -2147483648 -2147483643}
do_test rtree5-1.11 { 
  execsql { 
    INSERT INTO t1 VALUES(2, (1<<31)-5, (1<<31)-1, -1*(1<<31), -1*(1<<31)+5) 
  }
} {}
do_test rtree5-1.12 { 
  execsql { SELECT * FROM t1 WHERE id=2 }
} {2 2147483643 2147483647 -2147483648 -2147483643}

# This file contains suggested magic(5) text for the unix file(1)
# utility for recognizing SQLite3 databases.
#
# When SQLite is used as an application file format, it is desirable to
# have file(1) recognize the database file as being with the specific
# application.  You can set the application_id for a database file
# using:
#
#     PRAGMA application_id = INTEGER;
#
# INTEGER can be any signed 32-bit integer.  That integer is written as
# a 4-byte big-endian integer into offset 68 of the database header. 
#
# The Monotone application used "PRAGMA user_version=1598903374;" to set
# its identifier long before "PRAGMA application_id" became available.
# The user_version is very similar to application_id except that it is
# stored at offset 68 instead of offset 60.  The application_id pragma
# is preferred.  The rule using offset 60 for Monotone is for historical
# compatibility only.
#
0    string  =SQLite\ format\ 3
>68  belong  =0x0f055111  Fossil repository -
>68  belong  =0x0f055112  Fossil checkout - 
>68  belong  =0x0f055113  Fossil global configuration - 
>68  belong  =0x42654462  Bentley Systems BeSQLite Database -
>68  belong  =0x42654c6e  Bentley Systems Localization File -
>60  belong  =0x5f4d544e  Monotone source repository -
>0   string  =SQLite      SQLite3 database

# Object files for the SQLite library.
#
LIBOBJ+= alter.o analyze.o attach.o auth.o \
         backup.o bitvec.o btmutex.o btree.o build.o \
         callback.o complete.o ctime.o date.o delete.o expr.o fault.o fkey.o \
         fts3.o fts3_aux.o fts3_expr.o fts3_hash.o fts3_icu.o fts3_porter.o \
         fts3_snippet.o fts3_tokenizer.o fts3_tokenizer1.o \
         fts3_tokenize_vtab.o \
	 fts3_unicode.o fts3_unicode2.o \
         fts3_write.o func.o global.o hash.o \
         icu.o insert.o journal.o legacy.o loadext.o \
         main.o malloc.o mem0.o mem1.o mem2.o mem3.o mem5.o \
         memjournal.o \
         mutex.o mutex_noop.o mutex_unix.o mutex_w32.o \
         notify.o opcodes.o os.o os_unix.o os_win.o \

  $(TOP)/ext/fts3/fts3_hash.h \
  $(TOP)/ext/fts3/fts3_icu.c \
  $(TOP)/ext/fts3/fts3_porter.c \
  $(TOP)/ext/fts3/fts3_snippet.c \
  $(TOP)/ext/fts3/fts3_tokenizer.h \
  $(TOP)/ext/fts3/fts3_tokenizer.c \
  $(TOP)/ext/fts3/fts3_tokenizer1.c \
  $(TOP)/ext/fts3/fts3_tokenize_vtab.c \
  $(TOP)/ext/fts3/fts3_unicode.c \
  $(TOP)/ext/fts3/fts3_unicode2.c \
  $(TOP)/ext/fts3/fts3_write.c
SRC += \
  $(TOP)/ext/icu/sqliteicu.h \
  $(TOP)/ext/icu/icu.c
SRC += \

  $(TOP)/src/test_backup.c \
  $(TOP)/src/test_btree.c \
  $(TOP)/src/test_config.c \
  $(TOP)/src/test_demovfs.c \
  $(TOP)/src/test_devsym.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_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_stat.c \
  $(TOP)/src/test_sqllog.c \
  $(TOP)/src/test_superlock.c \
  $(TOP)/src/test_syscall.c \
  $(TOP)/src/test_tclvar.c \
  $(TOP)/src/test_thread.c \
  $(TOP)/src/test_vfs.c \
  $(TOP)/src/test_wsd.c

# Extensions to be statically loaded.
#
TESTSRC += \
  $(TOP)/ext/misc/amatch.c \
  $(TOP)/ext/misc/closure.c \
  $(TOP)/ext/misc/fuzzer.c \
  $(TOP)/ext/misc/ieee754.c \
  $(TOP)/ext/misc/nextchar.c \
  $(TOP)/ext/misc/regexp.c \
  $(TOP)/ext/misc/spellfix.c \
  $(TOP)/ext/misc/wholenumber.c


#TESTSRC += $(TOP)/ext/fts2/fts2_tokenizer.c
#TESTSRC += $(TOP)/ext/fts3/fts3_tokenizer.c

TESTSRC2 = \
  $(TOP)/src/attach.c \
  $(TOP)/src/backup.c \

	$(RANLIB) libsqlite3.a

sqlite3$(EXE):	$(TOP)/src/shell.c libsqlite3.a sqlite3.h
	$(TCCX) $(READLINE_FLAGS) -o sqlite3$(EXE)                  \
		$(TOP)/src/shell.c                                  \
		libsqlite3.a $(LIBREADLINE) $(TLIBS) $(THREADLIB)

mptester$(EXE):	sqlite3.c $(TOP)/mptest/mptest.c
	$(TCCX) -o $@ -I. $(TOP)/mptest/mptest.c sqlite3.c \
		$(TLIBS) $(THREADLIB)

sqlite3.o:	sqlite3.c
	$(TCCX) -c sqlite3.c

# This target creates a directory named "tsrc" and fills it with
# copies of all of the C source code and header files needed to
# build on the target system.  Some of the C source code and header
# files are automatically generated.  This target takes care of
# all that automatic generation.
#
target_source:	$(SRC) $(TOP)/tool/vdbe-compress.tcl
	rm -rf tsrc
	mkdir tsrc
	cp -f $(SRC) tsrc
	rm tsrc/sqlite.h.in tsrc/parse.y
	tclsh $(TOP)/tool/vdbe-compress.tcl <tsrc/vdbe.c >vdbe.new
	mv vdbe.new tsrc/vdbe.c
	touch target_source

sqlite3.c:	target_source $(TOP)/tool/mksqlite3c.tcl
	tclsh $(TOP)/tool/mksqlite3c.tcl
	cp tsrc/shell.c tsrc/sqlite3ext.h .
	echo '#ifndef USE_SYSTEM_SQLITE' >tclsqlite3.c
	cat sqlite3.c >>tclsqlite3.c
	echo '#endif /* USE_SYSTEM_SQLITE */' >>tclsqlite3.c
	cat $(TOP)/src/tclsqlite.c >>tclsqlite3.c

sqlite3.c-debug:	target_source $(TOP)/tool/mksqlite3c.tcl
	tclsh $(TOP)/tool/mksqlite3c.tcl --linemacros

	$(TCCX) -DSQLITE_CORE -c $(TOP)/ext/fts3/fts3_porter.c

fts3_tokenizer.o:	$(TOP)/ext/fts3/fts3_tokenizer.c $(HDR) $(EXTHDR)
	$(TCCX) -DSQLITE_CORE -c $(TOP)/ext/fts3/fts3_tokenizer.c

fts3_tokenizer1.o:	$(TOP)/ext/fts3/fts3_tokenizer1.c $(HDR) $(EXTHDR)
	$(TCCX) -DSQLITE_CORE -c $(TOP)/ext/fts3/fts3_tokenizer1.c

fts3_tokenize_vtab.o:	$(TOP)/ext/fts3/fts3_tokenize_vtab.c $(HDR) $(EXTHDR)
	$(TCCX) -DSQLITE_CORE -c $(TOP)/ext/fts3/fts3_tokenize_vtab.c

fts3_unicode.o:	$(TOP)/ext/fts3/fts3_unicode.c $(HDR) $(EXTHDR)
	$(TCCX) -DSQLITE_CORE -c $(TOP)/ext/fts3/fts3_unicode.c

fts3_unicode2.o:	$(TOP)/ext/fts3/fts3_unicode2.c $(HDR) $(EXTHDR)
	$(TCCX) -DSQLITE_CORE -c $(TOP)/ext/fts3/fts3_unicode2.c

	rm -rf tsrc target_source
	rm -f testloadext.dll libtestloadext.so
	rm -f amalgamation-testfixture amalgamation-testfixture.exe
	rm -f fts3-testfixture fts3-testfixture.exe
	rm -f testfixture testfixture.exe
	rm -f threadtest3 threadtest3.exe
	rm -f sqlite3.c fts?amal.c tclsqlite3.c
	rm -f sqlite3rc.h
	rm -f shell.c sqlite3ext.h
	rm -f sqlite3_analyzer sqlite3_analyzer.exe sqlite3_analyzer.c
	rm -f sqlite-*-output.vsix
	rm -f mptester mptester.exe

/*
** Configure five tasks in different ways, then run tests.
*/
--if vfsname() GLOB 'unix'
PRAGMA page_size=8192;
--task 1
  PRAGMA journal_mode=PERSIST;
  PRAGMA mmap_size=0;
--end
--task 2
  PRAGMA journal_mode=TRUNCATE;
  PRAGMA mmap_size=28672;
--end
--task 3
  PRAGMA journal_mode=MEMORY;
--end
--task 4
  PRAGMA journal_mode=OFF;
--end
--task 4
  PRAGMA mmap_size(268435456);
--end
--source multiwrite01.test
--wait all
PRAGMA page_size=16384;
VACUUM;
CREATE TABLE pgsz(taskid, sz INTEGER);
--task 1
  INSERT INTO pgsz VALUES(1, eval('PRAGMA page_size'));
--end
--task 2
  INSERT INTO pgsz VALUES(2, eval('PRAGMA page_size'));
--end
--task 3
  INSERT INTO pgsz VALUES(3, eval('PRAGMA page_size'));
--end
--task 4
  INSERT INTO pgsz VALUES(4, eval('PRAGMA page_size'));
--end
--task 5
  INSERT INTO pgsz VALUES(5, eval('PRAGMA page_size'));
--end
--source multiwrite01.test
--wait all
SELECT sz FROM pgsz;
--match 16384 16384 16384 16384 16384

/*
** Configure five tasks in different ways, then run tests.
*/
PRAGMA page_size=512;
--task 1
  PRAGMA mmap_size=0;
--end
--task 2
  PRAGMA mmap_size=28672;
--end
--task 3
  PRAGMA mmap_size=8192;
--end
--task 4
  PRAGMA mmap_size=65536;
--end
--task 5
  PRAGMA mmap_size=268435456;
--end
--source multiwrite01.test
--source crash02.subtest
PRAGMA page_size=1024;
VACUUM;
CREATE TABLE pgsz(taskid, sz INTEGER);
--task 1
  INSERT INTO pgsz VALUES(1, eval('PRAGMA page_size'));
--end
--task 2
  INSERT INTO pgsz VALUES(2, eval('PRAGMA page_size'));
--end
--task 3
  INSERT INTO pgsz VALUES(3, eval('PRAGMA page_size'));
--end
--task 4
  INSERT INTO pgsz VALUES(4, eval('PRAGMA page_size'));
--end
--task 5
  INSERT INTO pgsz VALUES(5, eval('PRAGMA page_size'));
--end
--source multiwrite01.test
--source crash02.subtest
--wait all
SELECT sz FROM pgsz;
--match 1024 1024 1024 1024 1024
PRAGMA page_size=2048;
VACUUM;
DELETE FROM pgsz;
--task 1
  INSERT INTO pgsz VALUES(1, eval('PRAGMA page_size'));
--end
--task 2
  INSERT INTO pgsz VALUES(2, eval('PRAGMA page_size'));
--end
--task 3
  INSERT INTO pgsz VALUES(3, eval('PRAGMA page_size'));
--end
--task 4
  INSERT INTO pgsz VALUES(4, eval('PRAGMA page_size'));
--end
--task 5
  INSERT INTO pgsz VALUES(5, eval('PRAGMA page_size'));
--end
--source multiwrite01.test
--source crash02.subtest
--wait all
SELECT sz FROM pgsz;
--match 2048 2048 2048 2048 2048
PRAGMA page_size=8192;
VACUUM;
DELETE FROM pgsz;
--task 1
  INSERT INTO pgsz VALUES(1, eval('PRAGMA page_size'));
--end
--task 2
  INSERT INTO pgsz VALUES(2, eval('PRAGMA page_size'));
--end
--task 3
  INSERT INTO pgsz VALUES(3, eval('PRAGMA page_size'));
--end
--task 4
  INSERT INTO pgsz VALUES(4, eval('PRAGMA page_size'));
--end
--task 5
  INSERT INTO pgsz VALUES(5, eval('PRAGMA page_size'));
--end
--source multiwrite01.test
--source crash02.subtest
--wait all
SELECT sz FROM pgsz;
--match 8192 8192 8192 8192 8192
PRAGMA page_size=16384;
VACUUM;
DELETE FROM pgsz;
--task 1
  INSERT INTO pgsz VALUES(1, eval('PRAGMA page_size'));
--end
--task 2
  INSERT INTO pgsz VALUES(2, eval('PRAGMA page_size'));
--end
--task 3
  INSERT INTO pgsz VALUES(3, eval('PRAGMA page_size'));
--end
--task 4
  INSERT INTO pgsz VALUES(4, eval('PRAGMA page_size'));
--end
--task 5
  INSERT INTO pgsz VALUES(5, eval('PRAGMA page_size'));
--end
--source multiwrite01.test
--source crash02.subtest
--wait all
SELECT sz FROM pgsz;
--match 16384 16384 16384 16384 16384
PRAGMA auto_vacuum=FULL;
VACUUM;
--source multiwrite01.test
--source crash02.subtest
--wait all
PRAGMA auto_vacuum=FULL;
PRAGMA page_size=512;
VACUUM;
--source multiwrite01.test
--source crash02.subtest

/* Test cases involving incomplete transactions that must be rolled back.
*/
--task 1
  DROP TABLE IF EXISTS t1;
  CREATE TABLE t1(a INTEGER PRIMARY KEY, b);
  --sleep 1
  INSERT INTO t1 VALUES(1, randomblob(2000));
  INSERT INTO t1 VALUES(2, randomblob(1000));
  --sleep 1
  INSERT INTO t1 SELECT a+2, randomblob(1500) FROM t1;
  INSERT INTO t1 SELECT a+4, randomblob(1500) FROM t1;
  INSERT INTO t1 SELECT a+8, randomblob(1500) FROM t1;
  --sleep 1
  INSERT INTO t1 SELECT a+16, randomblob(1500) FROM t1;
  --sleep 1
  INSERT INTO t1 SELECT a+32, randomblob(1500) FROM t1;
  SELECT count(*) FROM t1;
  --match 64
  SELECT avg(length(b)) FROM t1;
  --match 1500.0
  --sleep 2
  UPDATE t1 SET b='x'||a||'y';
  SELECT total(length(b)) FROM t1;
  --match 247
  SELECT a FROM t1 WHERE b='x17y';
  --match 17
  CREATE INDEX t1b ON t1(b);
  SELECT a FROM t1 WHERE b='x17y';
  --match 17
  SELECT a FROM t1 WHERE b GLOB 'x2?y' ORDER BY b DESC LIMIT 5;
  --match 29 28 27 26 25
--end
--wait 1
--task 2
  CREATE TABLE t2(a INTEGER PRIMARY KEY, b);
  INSERT INTO t2 SELECT a, b FROM t1;
  UPDATE t1 SET b='x'||a||'y';
  SELECT total(length(b)) FROM t2;
  --match 247
  SELECT a FROM t2 WHERE b='x17y';
  --match 17
  CREATE INDEX t2b ON t2(b);
  SELECT a FROM t2 WHERE b='x17y';
  --match 17
  SELECT a FROM t2 WHERE b GLOB 'x2?y' ORDER BY b DESC LIMIT 5;
  --match 29 28 27 26 25
--end
--task 3
  CREATE TABLE t3(a INTEGER PRIMARY KEY, b);
  INSERT INTO t3 SELECT a, b FROM t1;
  UPDATE t1 SET b='x'||a||'y';
  SELECT total(length(b)) FROM t3;
  --match 247
  SELECT a FROM t3 WHERE b='x17y';
  --match 17
  CREATE INDEX t3b ON t3(b);
  SELECT a FROM t3 WHERE b='x17y';
  --match 17
  SELECT a FROM t3 WHERE b GLOB 'x2?y' ORDER BY b DESC LIMIT 5;
  --match 29 28 27 26 25
--end
--task 4
  CREATE TABLE t4(a INTEGER PRIMARY KEY, b);
  INSERT INTO t4 SELECT a, b FROM t1;
  UPDATE t1 SET b='x'||a||'y';
  SELECT total(length(b)) FROM t4;
  --match 247
  SELECT a FROM t4 WHERE b='x17y';
  --match 17
  CREATE INDEX t4b ON t4(b);
  SELECT a FROM t4 WHERE b='x17y';
  --match 17
  SELECT a FROM t4 WHERE b GLOB 'x2?y' ORDER BY b DESC LIMIT 5;
  --match 29 28 27 26 25
--end
--task 5
  CREATE TABLE t5(a INTEGER PRIMARY KEY, b);
  INSERT INTO t5 SELECT a, b FROM t1;
  UPDATE t1 SET b='x'||a||'y';
  SELECT total(length(b)) FROM t5;
  --match 247
  SELECT a FROM t5 WHERE b='x17y';
  --match 17
  CREATE INDEX t5b ON t5(b);
  SELECT a FROM t5 WHERE b='x17y';
  --match 17
  SELECT a FROM t5 WHERE b GLOB 'x2?y' ORDER BY b DESC LIMIT 5;
  --match 29 28 27 26 25
--end

--wait all
/* After the database file has been set up, run the crash2 subscript
** multiple times. */
--source crash02.subtest
--source crash02.subtest
--source crash02.subtest
--source crash02.subtest
--source crash02.subtest
--source crash02.subtest
--source crash02.subtest
--source crash02.subtest
--source crash02.subtest

/*
** This script is called from crash01.test and config02.test and perhaps other
** script.  After the database file has been set up, make a big rollback 
** journal in client 1, then crash client 1.
** Then in the other clients, do an integrity check.
*/
--task 1 leave-hot-journal
  --sleep 5
  --finish
  PRAGMA cache_size=10;
  BEGIN;
  UPDATE t1 SET b=randomblob(20000);
  UPDATE t2 SET b=randomblob(20000);
  UPDATE t3 SET b=randomblob(20000);
  UPDATE t4 SET b=randomblob(20000);
  UPDATE t5 SET b=randomblob(20000);
  UPDATE t1 SET b=NULL;
  UPDATE t2 SET b=NULL;
  UPDATE t3 SET b=NULL;
  UPDATE t4 SET b=NULL;
  UPDATE t5 SET b=NULL;
  --print Task one crashing an incomplete transaction
  --exit 1
--end
--task 2 integrity_check-2
  SELECT count(*) FROM t1;
  --match 64
  --sleep 100
  PRAGMA integrity_check(10);
  --match ok
--end
--task 3 integrity_check-3
  SELECT count(*) FROM t1;
  --match 64
  --sleep 100
  PRAGMA integrity_check(10);
  --match ok
--end
--task 4 integrity_check-4
  SELECT count(*) FROM t1;
  --match 64
  --sleep 100
  PRAGMA integrity_check(10);
  --match ok
--end
--task 5 integrity_check-5
  SELECT count(*) FROM t1;
  --match 64
  --sleep 100
  PRAGMA integrity_check(10);
  --match ok
--end
--wait all

/*
** 2013-04-05
**
** 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.
**
*************************************************************************
** 
** This is a program used for testing SQLite, and specifically for testing
** the ability of independent processes to access the same SQLite database
** concurrently.
**
** Compile this program as follows:
**
**    gcc -g -c -Wall sqlite3.c $(OPTS)
**    gcc -g -o mptest mptest.c sqlite3.o $(LIBS)
**
** Recommended options:
**
**    -DHAVE_USLEEP
**    -DSQLITE_NO_SYNC
**    -DSQLITE_THREADSAFE=0
**    -DSQLITE_OMIT_LOAD_EXTENSION
**
** Run like this:
**
**     ./mptest $database $script
**
** where $database is the database to use for testing and $script is a
** test script.
*/
#include "sqlite3.h"
#include <stdio.h>
#if defined(_WIN32)
# define WIN32_LEAN_AND_MEAN
# include <windows.h>
#else
# include <unistd.h>
#endif
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <ctype.h>

/* The suffix to append to the child command lines, if any */
#if defined(_WIN32)
# define GETPID (int)GetCurrentProcessId
#else
# define GETPID getpid
#endif

/* Mark a parameter as unused to suppress compiler warnings */
#define UNUSED_PARAMETER(x)  (void)x

/* Global data
*/
static struct Global {
  char *argv0;           /* Name of the executable */
  const char *zVfs;      /* Name of VFS to use. Often NULL meaning "default" */
  char *zDbFile;         /* Name of the database */
  sqlite3 *db;           /* Open connection to database */
  char *zErrLog;         /* Filename for error log */
  FILE *pErrLog;         /* Where to write errors */
  char *zLog;            /* Name of output log file */
  FILE *pLog;            /* Where to write log messages */
  char zName[32];        /* Symbolic name of this process */
  int taskId;            /* Task ID.  0 means supervisor. */
  int iTrace;            /* Tracing level */
  int bSqlTrace;         /* True to trace SQL commands */
  int bIgnoreSqlErrors;  /* Ignore errors in SQL statements */
  int nError;            /* Number of errors */
  int nTest;             /* Number of --match operators */
  int iTimeout;          /* Milliseconds until a busy timeout */
  int bSync;             /* Call fsync() */
} g;

/* Default timeout */
#define DEFAULT_TIMEOUT 10000

/*
** Print a message adding zPrefix[] to the beginning of every line.
*/
static void printWithPrefix(FILE *pOut, const char *zPrefix, const char *zMsg){
  while( zMsg && zMsg[0] ){
    int i;
    for(i=0; zMsg[i] && zMsg[i]!='\n' && zMsg[i]!='\r'; i++){}
    fprintf(pOut, "%s%.*s\n", zPrefix, i, zMsg);
    zMsg += i;
    while( zMsg[0]=='\n' || zMsg[0]=='\r' ) zMsg++;
  }
}

/*
** Compare two pointers to strings, where the pointers might be NULL.
*/
static int safe_strcmp(const char *a, const char *b){
  if( a==b ) return 0;
  if( a==0 ) return -1;
  if( b==0 ) return 1;
  return strcmp(a,b);
}

/*
** Return TRUE if string z[] matches glob pattern zGlob[].
** Return FALSE if the pattern does not match.
**
** Globbing rules:
**
**      '*'       Matches any sequence of zero or more characters.
**
**      '?'       Matches exactly one character.
**
**     [...]      Matches one character from the enclosed list of
**                characters.
**
**     [^...]     Matches one character not in the enclosed list.
**
**      '#'       Matches any sequence of one or more digits with an
**                optional + or - sign in front
*/
int strglob(const char *zGlob, const char *z){
  int c, c2;
  int invert;
  int seen;

  while( (c = (*(zGlob++)))!=0 ){
    if( c=='*' ){
      while( (c=(*(zGlob++))) == '*' || c=='?' ){
        if( c=='?' && (*(z++))==0 ) return 0;
      }
      if( c==0 ){
        return 1;
      }else if( c=='[' ){
        while( *z && strglob(zGlob-1,z) ){
          z++;
        }
        return (*z)!=0;
      }
      while( (c2 = (*(z++)))!=0 ){
        while( c2!=c ){
          c2 = *(z++);
          if( c2==0 ) return 0;
        }
        if( strglob(zGlob,z) ) return 1;
      }
      return 0;
    }else if( c=='?' ){
      if( (*(z++))==0 ) return 0;
    }else if( c=='[' ){
      int prior_c = 0;
      seen = 0;
      invert = 0;
      c = *(z++);
      if( c==0 ) return 0;
      c2 = *(zGlob++);
      if( c2=='^' ){
        invert = 1;
        c2 = *(zGlob++);
      }
      if( c2==']' ){
        if( c==']' ) seen = 1;
        c2 = *(zGlob++);
      }
      while( c2 && c2!=']' ){
        if( c2=='-' && zGlob[0]!=']' && zGlob[0]!=0 && prior_c>0 ){
          c2 = *(zGlob++);
          if( c>=prior_c && c<=c2 ) seen = 1;
          prior_c = 0;
        }else{
          if( c==c2 ){
            seen = 1;
          }
          prior_c = c2;
        }
        c2 = *(zGlob++);
      }
      if( c2==0 || (seen ^ invert)==0 ) return 0;
    }else if( c=='#' ){
      if( (z[0]=='-' || z[0]=='+') && isdigit(z[1]) ) z++;
      if( !isdigit(z[0]) ) return 0;
      z++;
      while( isdigit(z[0]) ){ z++; }
    }else{
      if( c!=(*(z++)) ) return 0;
    }
  }
  return *z==0;
}

/*
** Close output stream pOut if it is not stdout or stderr
*/
static void maybeClose(FILE *pOut){
  if( pOut!=stdout && pOut!=stderr ) fclose(pOut);
}

/*
** Print an error message
*/
static void errorMessage(const char *zFormat, ...){
  va_list ap;
  char *zMsg;
  char zPrefix[30];
  va_start(ap, zFormat);
  zMsg = sqlite3_vmprintf(zFormat, ap);
  va_end(ap);
  sqlite3_snprintf(sizeof(zPrefix), zPrefix, "%s:ERROR: ", g.zName);
  if( g.pLog ){
    printWithPrefix(g.pLog, zPrefix, zMsg);
    fflush(g.pLog);
  }
  if( g.pErrLog && safe_strcmp(g.zErrLog,g.zLog) ){
    printWithPrefix(g.pErrLog, zPrefix, zMsg);
    fflush(g.pErrLog);
  }
  sqlite3_free(zMsg);
  g.nError++;
}

/* Forward declaration */
static int trySql(const char*, ...);

/*
** Print an error message and then quit.
*/
static void fatalError(const char *zFormat, ...){
  va_list ap;
  char *zMsg;
  char zPrefix[30];
  va_start(ap, zFormat);
  zMsg = sqlite3_vmprintf(zFormat, ap);
  va_end(ap);
  sqlite3_snprintf(sizeof(zPrefix), zPrefix, "%s:FATAL: ", g.zName);
  if( g.pLog ){
    printWithPrefix(g.pLog, zPrefix, zMsg);
    fflush(g.pLog);
    maybeClose(g.pLog);
  }
  if( g.pErrLog && safe_strcmp(g.zErrLog,g.zLog) ){
    printWithPrefix(g.pErrLog, zPrefix, zMsg);
    fflush(g.pErrLog);
    maybeClose(g.pErrLog);
  }
  sqlite3_free(zMsg);
  if( g.db ){
    int nTry = 0;
    g.iTimeout = 0;
    while( trySql("UPDATE client SET wantHalt=1;")==SQLITE_BUSY
           && (nTry++)<100 ){
      sqlite3_sleep(10);
    }
  }
  sqlite3_close(g.db);
  exit(1);  
}


/*
** Print a log message
*/
static void logMessage(const char *zFormat, ...){
  va_list ap;
  char *zMsg;
  char zPrefix[30];
  va_start(ap, zFormat);
  zMsg = sqlite3_vmprintf(zFormat, ap);
  va_end(ap);
  sqlite3_snprintf(sizeof(zPrefix), zPrefix, "%s: ", g.zName);
  if( g.pLog ){
    printWithPrefix(g.pLog, zPrefix, zMsg);
    fflush(g.pLog);
  }
  sqlite3_free(zMsg);
}

/*
** Return the length of a string omitting trailing whitespace
*/
static int clipLength(const char *z){
  int n = (int)strlen(z);
  while( n>0 && isspace(z[n-1]) ){ n--; }
  return n;
}

/*
** Auxiliary SQL function to return the name of the VFS
*/
static void vfsNameFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  sqlite3 *db = sqlite3_context_db_handle(context);
  char *zVfs = 0;
  UNUSED_PARAMETER(argc);
  UNUSED_PARAMETER(argv);
  sqlite3_file_control(db, "main", SQLITE_FCNTL_VFSNAME, &zVfs);
  if( zVfs ){
    sqlite3_result_text(context, zVfs, -1, sqlite3_free);
  }
}

/*
** Busy handler with a g.iTimeout-millisecond timeout
*/
static int busyHandler(void *pCD, int count){
  UNUSED_PARAMETER(pCD);
  if( count*10>g.iTimeout ){
    if( g.iTimeout>0 ) errorMessage("timeout after %dms", g.iTimeout);
    return 0;
  }
  sqlite3_sleep(10);
  return 1;
}

/*
** SQL Trace callback
*/
static void sqlTraceCallback(void *NotUsed1, const char *zSql){
  UNUSED_PARAMETER(NotUsed1);
  logMessage("[%.*s]", clipLength(zSql), zSql);
}

/*
** SQL error log callback
*/
static void sqlErrorCallback(void *pArg, int iErrCode, const char *zMsg){
  UNUSED_PARAMETER(pArg);
  if( iErrCode==SQLITE_ERROR && g.bIgnoreSqlErrors ) return;
  if( (iErrCode&0xff)==SQLITE_SCHEMA && g.iTrace<3 ) return;
  if( g.iTimeout==0 && (iErrCode&0xff)==SQLITE_BUSY && g.iTrace<3 ) return;
  if( (iErrCode&0xff)==SQLITE_NOTICE ){
    logMessage("(info) %s", zMsg);
  }else{
    errorMessage("(errcode=%d) %s", iErrCode, zMsg);
  }
}

/*
** Prepare an SQL statement.  Issue a fatal error if unable.
*/
static sqlite3_stmt *prepareSql(const char *zFormat, ...){
  va_list ap;
  char *zSql;
  int rc;
  sqlite3_stmt *pStmt = 0;
  va_start(ap, zFormat);
  zSql = sqlite3_vmprintf(zFormat, ap);
  va_end(ap);
  rc = sqlite3_prepare_v2(g.db, zSql, -1, &pStmt, 0);
  if( rc!=SQLITE_OK ){
    sqlite3_finalize(pStmt);
    fatalError("%s\n%s\n", sqlite3_errmsg(g.db), zSql);
  }
  sqlite3_free(zSql);
  return pStmt;
}

/*
** Run arbitrary SQL.  Issue a fatal error on failure.
*/
static void runSql(const char *zFormat, ...){
  va_list ap;
  char *zSql;
  int rc;
  va_start(ap, zFormat);
  zSql = sqlite3_vmprintf(zFormat, ap);
  va_end(ap);
  rc = sqlite3_exec(g.db, zSql, 0, 0, 0);
  if( rc!=SQLITE_OK ){
    fatalError("%s\n%s\n", sqlite3_errmsg(g.db), zSql);
  }
  sqlite3_free(zSql);
}

/*
** Try to run arbitrary SQL.  Return success code.
*/
static int trySql(const char *zFormat, ...){
  va_list ap;
  char *zSql;
  int rc;
  va_start(ap, zFormat);
  zSql = sqlite3_vmprintf(zFormat, ap);
  va_end(ap);
  rc = sqlite3_exec(g.db, zSql, 0, 0, 0);
  sqlite3_free(zSql);
  return rc;
}

/* Structure for holding an arbitrary length string
*/
typedef struct String String;
struct String {
  char *z;         /* the string */
  int n;           /* Slots of z[] used */
  int nAlloc;      /* Slots of z[] allocated */
};

/* Free a string */
static void stringFree(String *p){
  if( p->z ) sqlite3_free(p->z);
  memset(p, 0, sizeof(*p));
}

/* Append n bytes of text to a string.  If n<0 append the entire string. */
static void stringAppend(String *p, const char *z, int n){
  if( n<0 ) n = (int)strlen(z);
  if( p->n+n>=p->nAlloc ){
    int nAlloc = p->nAlloc*2 + n + 100;
    char *z = sqlite3_realloc(p->z, nAlloc);
    if( z==0 ) fatalError("out of memory");
    p->z = z;
    p->nAlloc = nAlloc;
  }
  memcpy(p->z+p->n, z, n);
  p->n += n;
  p->z[p->n] = 0;
}

/* Reset a string to an empty string */
static void stringReset(String *p){
  if( p->z==0 ) stringAppend(p, " ", 1);
  p->n = 0;
  p->z[0] = 0;
}

/* Append a new token onto the end of the string */
static void stringAppendTerm(String *p, const char *z){
  int i;
  if( p->n ) stringAppend(p, " ", 1);
  if( z==0 ){
    stringAppend(p, "nil", 3);
    return;
  }
  for(i=0; z[i] && !isspace(z[i]); i++){}
  if( i>0 && z[i]==0 ){
    stringAppend(p, z, i);
    return;
  }
  stringAppend(p, "'", 1);
  while( z[0] ){
    for(i=0; z[i] && z[i]!='\''; i++){}
    if( z[i] ){
      stringAppend(p, z, i+1);
      stringAppend(p, "'", 1);
      z += i+1;
    }else{
      stringAppend(p, z, i);
      break;
    }
  }
  stringAppend(p, "'", 1);
}

/*
** Callback function for evalSql()
*/
static int evalCallback(void *pCData, int argc, char **argv, char **azCol){
  String *p = (String*)pCData;
  int i;
  UNUSED_PARAMETER(azCol);
  for(i=0; i<argc; i++) stringAppendTerm(p, argv[i]);
  return 0;
}

/*
** Run arbitrary SQL and record the results in an output string
** given by the first parameter.
*/
static int evalSql(String *p, const char *zFormat, ...){
  va_list ap;
  char *zSql;
  int rc;
  char *zErrMsg = 0;
  va_start(ap, zFormat);
  zSql = sqlite3_vmprintf(zFormat, ap);
  va_end(ap);
  assert( g.iTimeout>0 );
  rc = sqlite3_exec(g.db, zSql, evalCallback, p, &zErrMsg);
  sqlite3_free(zSql);
  if( rc ){
    char zErr[30];
    sqlite3_snprintf(sizeof(zErr), zErr, "error(%d)", rc);
    stringAppendTerm(p, zErr);
    if( zErrMsg ){
      stringAppendTerm(p, zErrMsg);
      sqlite3_free(zErrMsg);
    }
  }
  return rc;
}

/*
** Auxiliary SQL function to recursively evaluate SQL.
*/
static void evalFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  sqlite3 *db = sqlite3_context_db_handle(context);
  const char *zSql = (const char*)sqlite3_value_text(argv[0]);
  String res;
  char *zErrMsg = 0;
  int rc;
  UNUSED_PARAMETER(argc);
  memset(&res, 0, sizeof(res));
  rc = sqlite3_exec(db, zSql, evalCallback, &res, &zErrMsg);
  if( zErrMsg ){
    sqlite3_result_error(context, zErrMsg, -1);
    sqlite3_free(zErrMsg);
  }else if( rc ){
    sqlite3_result_error_code(context, rc);
  }else{
    sqlite3_result_text(context, res.z, -1, SQLITE_TRANSIENT);
  }
  stringFree(&res);
}

/*
** Look up the next task for client iClient in the database.
** Return the task script and the task number and mark that
** task as being under way.
*/
static int startScript(
  int iClient,              /* The client number */
  char **pzScript,          /* Write task script here */
  int *pTaskId,             /* Write task number here */
  char **pzTaskName         /* Name of the task */
){
  sqlite3_stmt *pStmt = 0;
  int taskId;
  int rc;
  int totalTime = 0;

  *pzScript = 0;
  g.iTimeout = 0;
  while(1){
    rc = trySql("BEGIN IMMEDIATE");
    if( rc==SQLITE_BUSY ){
      sqlite3_sleep(10);
      totalTime += 10;
      continue;
    }
    if( rc!=SQLITE_OK ){
      fatalError("in startScript: %s", sqlite3_errmsg(g.db));
    }
    if( g.nError || g.nTest ){
      runSql("UPDATE counters SET nError=nError+%d, nTest=nTest+%d",
             g.nError, g.nTest);
      g.nError = 0;
      g.nTest = 0;
    }
    pStmt = prepareSql("SELECT 1 FROM client WHERE id=%d AND wantHalt",iClient);
    rc = sqlite3_step(pStmt);
    sqlite3_finalize(pStmt);
    if( rc==SQLITE_ROW ){
      runSql("DELETE FROM client WHERE id=%d", iClient);
      g.iTimeout = DEFAULT_TIMEOUT;
      runSql("COMMIT TRANSACTION;");
      return SQLITE_DONE;
    }
    pStmt = prepareSql(
              "SELECT script, id, name FROM task"
              " WHERE client=%d AND starttime IS NULL"
              " ORDER BY id LIMIT 1", iClient);
    rc = sqlite3_step(pStmt);
    if( rc==SQLITE_ROW ){
      int n = sqlite3_column_bytes(pStmt, 0);
      *pzScript = sqlite3_malloc(n+1);
      strcpy(*pzScript, (const char*)sqlite3_column_text(pStmt, 0));
      *pTaskId = taskId = sqlite3_column_int(pStmt, 1);
      *pzTaskName = sqlite3_mprintf("%s", sqlite3_column_text(pStmt, 2));
      sqlite3_finalize(pStmt);
      runSql("UPDATE task"
             "   SET starttime=strftime('%%Y-%%m-%%d %%H:%%M:%%f','now')"
             " WHERE id=%d;", taskId);
      g.iTimeout = DEFAULT_TIMEOUT;
      runSql("COMMIT TRANSACTION;");
      return SQLITE_OK;
    }
    sqlite3_finalize(pStmt);
    if( rc==SQLITE_DONE ){
      if( totalTime>30000 ){
        errorMessage("Waited over 30 seconds with no work.  Giving up.");
        runSql("DELETE FROM client WHERE id=%d; COMMIT;", iClient);
        sqlite3_close(g.db);
        exit(1);
      }
      while( trySql("COMMIT")==SQLITE_BUSY ){
        sqlite3_sleep(10);
        totalTime += 10;
      }
      sqlite3_sleep(100);
      totalTime += 100;
      continue;
    }
    fatalError("%s", sqlite3_errmsg(g.db));
  }
  g.iTimeout = DEFAULT_TIMEOUT;
}

/*
** Mark a script as having finished.   Remove the CLIENT table entry
** if bShutdown is true.
*/
static int finishScript(int iClient, int taskId, int bShutdown){
  runSql("UPDATE task"
         "   SET endtime=strftime('%%Y-%%m-%%d %%H:%%M:%%f','now')"
         " WHERE id=%d;", taskId);
  if( bShutdown ){
    runSql("DELETE FROM client WHERE id=%d", iClient);
  }
  return SQLITE_OK;
}

/*
** Start up a client process for iClient, if it is not already
** running.  If the client is already running, then this routine
** is a no-op.
*/
static void startClient(int iClient){
  runSql("INSERT OR IGNORE INTO client VALUES(%d,0)", iClient);
  if( sqlite3_changes(g.db) ){
    char *zSys;
    int rc;
    zSys = sqlite3_mprintf("%s \"%s\" --client %d --trace %d",
                 g.argv0, g.zDbFile, iClient, g.iTrace);
    if( g.bSqlTrace ){
      zSys = sqlite3_mprintf("%z --sqltrace", zSys);
    }
    if( g.bSync ){
      zSys = sqlite3_mprintf("%z --sync", zSys);
    }
    if( g.zVfs ){
      zSys = sqlite3_mprintf("%z --vfs \"%s\"", zSys, g.zVfs);
    }
    if( g.iTrace>=2 ) logMessage("system('%q')", zSys);
#if !defined(_WIN32)
    zSys = sqlite3_mprintf("%z &", zSys);
    rc = system(zSys);
    if( rc ) errorMessage("system() fails with error code %d", rc);
#else
    {
      STARTUPINFOA startupInfo;
      PROCESS_INFORMATION processInfo;
      memset(&startupInfo, 0, sizeof(startupInfo));
      startupInfo.cb = sizeof(startupInfo);
      memset(&processInfo, 0, sizeof(processInfo));
      rc = CreateProcessA(NULL, zSys, NULL, NULL, FALSE, 0, NULL, NULL,
                        &startupInfo, &processInfo);
      if( rc ){
        CloseHandle(processInfo.hThread);
        CloseHandle(processInfo.hProcess);
      }else{
        errorMessage("CreateProcessA() fails with error code %lu",
                     GetLastError());
      }
    }
#endif
    sqlite3_free(zSys);
  }
}

/*
** Read the entire content of a file into memory
*/
static char *readFile(const char *zFilename){
  FILE *in = fopen(zFilename, "rb");
  long sz;
  char *z;
  if( in==0 ){
    fatalError("cannot open \"%s\" for reading", zFilename);
  }
  fseek(in, 0, SEEK_END);
  sz = ftell(in);
  rewind(in);
  z = sqlite3_malloc( sz+1 );
  sz = (long)fread(z, 1, sz, in);
  z[sz] = 0;
  fclose(in);
  return z;
}

/*
** Return the length of the next token.
*/
static int tokenLength(const char *z, int *pnLine){
  int n = 0;
  if( isspace(z[0]) || (z[0]=='/' && z[1]=='*') ){
    int inC = 0;
    int c;
    if( z[0]=='/' ){
      inC = 1;
      n = 2;
    }
    while( (c = z[n++])!=0 ){
      if( c=='\n' ) (*pnLine)++;
      if( isspace(c) ) continue;
      if( inC && c=='*' && z[n]=='/' ){
        n++;
        inC = 0;
      }else if( !inC && c=='/' && z[n]=='*' ){
        n++;
        inC = 1;
      }else if( !inC ){
        break;
      }
    }
    n--;
  }else if( z[0]=='-' && z[1]=='-' ){
    for(n=2; z[n] && z[n]!='\n'; n++){}
    if( z[n] ){ (*pnLine)++; n++; }
  }else if( z[0]=='"' || z[0]=='\'' ){
    int delim = z[0];
    for(n=1; z[n]; n++){
      if( z[n]=='\n' ) (*pnLine)++;
      if( z[n]==delim ){
        n++;
        if( z[n+1]!=delim ) break;
      }
    }
  }else{
    int c;
    for(n=1; (c = z[n])!=0 && !isspace(c) && c!='"' && c!='\'' && c!=';'; n++){}
  }
  return n;
}

/*
** Copy a single token into a string buffer.
*/
static int extractToken(const char *zIn, int nIn, char *zOut, int nOut){
  int i;
  if( nIn<=0 ){
    zOut[0] = 0;
    return 0;
  }
  for(i=0; i<nIn && i<nOut-1 && !isspace(zIn[i]); i++){ zOut[i] = zIn[i]; }
  zOut[i] = 0;
  return i;
}

/*
** Find the number of characters up to the start of the next "--end" token.
*/
static int findEnd(const char *z, int *pnLine){
  int n = 0;
  while( z[n] && (strncmp(z+n,"--end",5) || !isspace(z[n+5])) ){
    n += tokenLength(z+n, pnLine);
  }
  return n;
}

/*
** Find the number of characters up to the first character past the
** of the next "--endif"  or "--else" token. Nested --if commands are
** also skipped.
*/
static int findEndif(const char *z, int stopAtElse, int *pnLine){
  int n = 0;
  while( z[n] ){
    int len = tokenLength(z+n, pnLine);
    if( (strncmp(z+n,"--endif",7)==0 && isspace(z[n+7]))
     || (stopAtElse && strncmp(z+n,"--else",6)==0 && isspace(z[n+6]))
    ){
      return n+len;
    }
    if( strncmp(z+n,"--if",4)==0 && isspace(z[n+4]) ){
      int skip = findEndif(z+n+len, 0, pnLine);
      n += skip + len;
    }else{
      n += len;
    }
  }
  return n;
}

/*
** Wait for a client process to complete all its tasks
*/
static void waitForClient(int iClient, int iTimeout, char *zErrPrefix){
  sqlite3_stmt *pStmt;
  int rc;
  if( iClient>0 ){
    pStmt = prepareSql(
               "SELECT 1 FROM task"
               " WHERE client=%d"
               "   AND client IN (SELECT id FROM client)"
               "  AND endtime IS NULL",
               iClient);
  }else{
    pStmt = prepareSql(
               "SELECT 1 FROM task"
               " WHERE client IN (SELECT id FROM client)"
               "   AND endtime IS NULL");
  }
  g.iTimeout = 0;
  while( ((rc = sqlite3_step(pStmt))==SQLITE_BUSY || rc==SQLITE_ROW)
    && iTimeout>0
  ){
    sqlite3_reset(pStmt);
    sqlite3_sleep(50);
    iTimeout -= 50;
  }
  sqlite3_finalize(pStmt);
  g.iTimeout = DEFAULT_TIMEOUT;
  if( rc!=SQLITE_DONE ){
    if( zErrPrefix==0 ) zErrPrefix = "";
    if( iClient>0 ){
      errorMessage("%stimeout waiting for client %d", zErrPrefix, iClient);
    }else{
      errorMessage("%stimeout waiting for all clients", zErrPrefix);
    }
  }
}

/* Return a pointer to the tail of a filename
*/
static char *filenameTail(char *z){
  int i, j;
  for(i=j=0; z[i]; i++) if( z[i]=='/' ) j = i+1;
  return z+j;
}

/*
** Interpret zArg as a boolean value.  Return either 0 or 1.
*/
static int booleanValue(char *zArg){
  int i;
  if( zArg==0 ) return 0;
  for(i=0; zArg[i]>='0' && zArg[i]<='9'; i++){}
  if( i>0 && zArg[i]==0 ) return atoi(zArg);
  if( sqlite3_stricmp(zArg, "on")==0 || sqlite3_stricmp(zArg,"yes")==0 ){
    return 1;
  }
  if( sqlite3_stricmp(zArg, "off")==0 || sqlite3_stricmp(zArg,"no")==0 ){
    return 0;
  }
  errorMessage("unknown boolean: [%s]", zArg);
  return 0;
}


/* This routine exists as a convenient place to set a debugger
** breakpoint.
*/
static void test_breakpoint(void){ static volatile int cnt = 0; cnt++; }

/* Maximum number of arguments to a --command */
#define MX_ARG 2

/*
** Run a script.
*/
static void runScript(
  int iClient,       /* The client number, or 0 for the master */
  int taskId,        /* The task ID for clients.  0 for master */
  char *zScript,     /* Text of the script */
  char *zFilename    /* File from which script was read. */
){
  int lineno = 1;
  int prevLine = 1;
  int ii = 0;
  int iBegin = 0;
  int n, c, j;
  int len;
  int nArg;
  String sResult;
  char zCmd[30];
  char zError[1000];
  char azArg[MX_ARG][100];

  memset(&sResult, 0, sizeof(sResult));
  stringReset(&sResult);
  while( (c = zScript[ii])!=0 ){
    prevLine = lineno;
    len = tokenLength(zScript+ii, &lineno);
    if( isspace(c) || (c=='/' && zScript[ii+1]=='*') ){
      ii += len;
      continue;
    }
    if( c!='-' || zScript[ii+1]!='-' || !isalpha(zScript[ii+2]) ){
      ii += len;
      continue;
    }

    /* Run any prior SQL before processing the new --command */
    if( ii>iBegin ){
      char *zSql = sqlite3_mprintf("%.*s", ii-iBegin, zScript+iBegin);
      evalSql(&sResult, zSql);
      sqlite3_free(zSql);
      iBegin = ii + len;
    }

    /* Parse the --command */
    if( g.iTrace>=2 ) logMessage("%.*s", len, zScript+ii);
    n = extractToken(zScript+ii+2, len-2, zCmd, sizeof(zCmd));
    for(nArg=0; n<len-2 && nArg<MX_ARG; nArg++){
      while( n<len-2 && isspace(zScript[ii+2+n]) ){ n++; }
      if( n>=len-2 ) break;
      n += extractToken(zScript+ii+2+n, len-2-n,
                        azArg[nArg], sizeof(azArg[nArg]));
    }
    for(j=nArg; j<MX_ARG; j++) azArg[j++][0] = 0;

    /*
    **  --sleep N
    **
    ** Pause for N milliseconds
    */
    if( strcmp(zCmd, "sleep")==0 ){
      sqlite3_sleep(atoi(azArg[0]));
    }else 

    /*
    **   --exit N
    **
    ** Exit this process.  If N>0 then exit without shutting down
    ** SQLite.  (In other words, simulate a crash.)
    */
    if( strcmp(zCmd, "exit")==0 ){
      int rc = atoi(azArg[0]);
      finishScript(iClient, taskId, 1);
      if( rc==0 ) sqlite3_close(g.db);
      exit(rc);
    }else

    /*
    **   --testcase NAME
    **
    ** Begin a new test case.  Announce in the log that the test case
    ** has begun.
    */
    if( strcmp(zCmd, "testcase")==0 ){
      if( g.iTrace==1 ) logMessage("%.*s", len - 1, zScript+ii);
      stringReset(&sResult);
    }else

    /*
    **   --finish
    **
    ** Mark the current task as having finished, even if it is not.
    ** This can be used in conjunction with --exit to simulate a crash.
    */
    if( strcmp(zCmd, "finish")==0 && iClient>0 ){
      finishScript(iClient, taskId, 1);
    }else

    /*
    **  --reset
    **
    ** Reset accumulated results back to an empty string
    */
    if( strcmp(zCmd, "reset")==0 ){
      stringReset(&sResult);
    }else

    /*
    **  --match ANSWER...
    **
    ** Check to see if output matches ANSWER.  Report an error if not.
    */
    if( strcmp(zCmd, "match")==0 ){
      int jj;
      char *zAns = zScript+ii;
      for(jj=7; jj<len-1 && isspace(zAns[jj]); jj++){}
      zAns += jj;
      if( len-jj-1!=sResult.n || strncmp(sResult.z, zAns, len-jj-1) ){
        errorMessage("line %d of %s:\nExpected [%.*s]\n     Got [%s]",
          prevLine, zFilename, len-jj-1, zAns, sResult.z);
      }
      g.nTest++;
      stringReset(&sResult);
    }else

    /*
    **  --glob ANSWER...
    **  --notglob ANSWER....
    **
    ** Check to see if output does or does not match the glob pattern
    ** ANSWER.
    */
    if( strcmp(zCmd, "glob")==0 || strcmp(zCmd, "notglob")==0 ){
      int jj;
      char *zAns = zScript+ii;
      char *zCopy;
      int isGlob = (zCmd[0]=='g');
      for(jj=9-3*isGlob; jj<len-1 && isspace(zAns[jj]); jj++){}
      zAns += jj;
      zCopy = sqlite3_mprintf("%.*s", len-jj-1, zAns);
      if( (sqlite3_strglob(zCopy, sResult.z)==0)^isGlob ){
        errorMessage("line %d of %s:\nExpected [%s]\n     Got [%s]",
          prevLine, zFilename, zCopy, sResult.z);
      }
      sqlite3_free(zCopy);
      g.nTest++;
      stringReset(&sResult);
    }else

    /*
    **  --output
    **
    ** Output the result of the previous SQL.
    */
    if( strcmp(zCmd, "output")==0 ){
      logMessage("%s", sResult.z);
    }else

    /*
    **  --source FILENAME
    **
    ** Run a subscript from a separate file.
    */
    if( strcmp(zCmd, "source")==0 ){
      char *zNewFile, *zNewScript;
      char *zToDel = 0;
      zNewFile = azArg[0];
      if( zNewFile[0]!='/' ){
        int k;
        for(k=(int)strlen(zFilename)-1; k>=0 && zFilename[k]!='/'; k--){}
        if( k>0 ){
          zNewFile = zToDel = sqlite3_mprintf("%.*s/%s", k,zFilename,zNewFile);
        }
      }
      zNewScript = readFile(zNewFile);
      if( g.iTrace ) logMessage("begin script [%s]\n", zNewFile);
      runScript(0, 0, zNewScript, zNewFile);
      sqlite3_free(zNewScript);
      if( g.iTrace ) logMessage("end script [%s]\n", zNewFile);
      sqlite3_free(zToDel);
    }else

    /*
    **  --print MESSAGE....
    **
    ** Output the remainder of the line to the log file
    */
    if( strcmp(zCmd, "print")==0 ){
      int jj;
      for(jj=7; jj<len && isspace(zScript[ii+jj]); jj++){}
      logMessage("%.*s", len-jj, zScript+ii+jj);
    }else

    /*
    **  --if EXPR
    **
    ** Skip forward to the next matching --endif or --else if EXPR is false.
    */
    if( strcmp(zCmd, "if")==0 ){
      int jj, rc;
      sqlite3_stmt *pStmt;
      for(jj=4; jj<len && isspace(zScript[ii+jj]); jj++){}
      pStmt = prepareSql("SELECT %.*s", len-jj, zScript+ii+jj);
      rc = sqlite3_step(pStmt);
      if( rc!=SQLITE_ROW || sqlite3_column_int(pStmt, 0)==0 ){
        ii += findEndif(zScript+ii+len, 1, &lineno);
      }
      sqlite3_finalize(pStmt);
    }else

    /*
    **  --else
    **
    ** This command can only be encountered if currently inside an --if that
    ** is true.  Skip forward to the next matching --endif.
    */
    if( strcmp(zCmd, "else")==0 ){
      ii += findEndif(zScript+ii+len, 0, &lineno);
    }else

    /*
    **  --endif
    **
    ** This command can only be encountered if currently inside an --if that
    ** is true or an --else of a false if.  This is a no-op.
    */
    if( strcmp(zCmd, "endif")==0 ){
      /* no-op */
    }else

    /*
    **  --start CLIENT
    **
    ** Start up the given client.
    */
    if( strcmp(zCmd, "start")==0 && iClient==0 ){
      int iNewClient = atoi(azArg[0]);
      if( iNewClient>0 ){
        startClient(iNewClient);
      }
    }else

    /*
    **  --wait CLIENT TIMEOUT
    **
    ** Wait until all tasks complete for the given client.  If CLIENT is
    ** "all" then wait for all clients to complete.  Wait no longer than
    ** TIMEOUT milliseconds (default 10,000)
    */
    if( strcmp(zCmd, "wait")==0 && iClient==0 ){
      int iTimeout = nArg>=2 ? atoi(azArg[1]) : 10000;
      sqlite3_snprintf(sizeof(zError),zError,"line %d of %s\n",
                       prevLine, zFilename);
      waitForClient(atoi(azArg[0]), iTimeout, zError);
    }else

    /*
    **  --task CLIENT
    **     <task-content-here>
    **  --end
    **
    ** Assign work to a client.  Start the client if it is not running
    ** already.
    */
    if( strcmp(zCmd, "task")==0 && iClient==0 ){
      int iTarget = atoi(azArg[0]);
      int iEnd;
      char *zTask;
      char *zTName;
      iEnd = findEnd(zScript+ii+len, &lineno);
      if( iTarget<0 ){
        errorMessage("line %d of %s: bad client number: %d",
                     prevLine, zFilename, iTarget);
      }else{
        zTask = sqlite3_mprintf("%.*s", iEnd, zScript+ii+len);
        if( nArg>1 ){
          zTName = sqlite3_mprintf("%s", azArg[1]);
        }else{
          zTName = sqlite3_mprintf("%s:%d", filenameTail(zFilename), prevLine);
        }
        startClient(iTarget);
        runSql("INSERT INTO task(client,script,name)"
               " VALUES(%d,'%q',%Q)", iTarget, zTask, zTName);
        sqlite3_free(zTask);
        sqlite3_free(zTName);
      }
      iEnd += tokenLength(zScript+ii+len+iEnd, &lineno);
      len += iEnd;
      iBegin = ii+len;
    }else

    /*
    **  --breakpoint
    **
    ** This command calls "test_breakpoint()" which is a routine provided
    ** as a convenient place to set a debugger breakpoint.
    */
    if( strcmp(zCmd, "breakpoint")==0 ){
      test_breakpoint();
    }else

    /*
    **  --show-sql-errors BOOLEAN
    **
    ** Turn display of SQL errors on and off.
    */
    if( strcmp(zCmd, "show-sql-errors")==0 ){
      g.bIgnoreSqlErrors = nArg>=1 ? !booleanValue(azArg[0]) : 1;
    }else


    /* error */{
      errorMessage("line %d of %s: unknown command --%s",
                   prevLine, zFilename, zCmd);
    }
    ii += len;
  }
  if( iBegin<ii ){
    char *zSql = sqlite3_mprintf("%.*s", ii-iBegin, zScript+iBegin);
    runSql(zSql);
    sqlite3_free(zSql);
  }
  stringFree(&sResult);
}

/*
** Look for a command-line option.  If present, return a pointer.
** Return NULL if missing.
**
** hasArg==0 means the option is a flag.  It is either present or not.
** hasArg==1 means the option has an argument.  Return a pointer to the
** argument.
*/
static char *findOption(
  char **azArg,
  int *pnArg,
  const char *zOption,
  int hasArg
){
  int i, j;
  char *zReturn = 0;
  int nArg = *pnArg;

  assert( hasArg==0 || hasArg==1 );
  for(i=0; i<nArg; i++){
    const char *z;
    if( i+hasArg >= nArg ) break;
    z = azArg[i];
    if( z[0]!='-' ) continue;
    z++;
    if( z[0]=='-' ){
      if( z[1]==0 ) break;
      z++;
    }
    if( strcmp(z,zOption)==0 ){
      if( hasArg && i==nArg-1 ){
        fatalError("command-line option \"--%s\" requires an argument", z);
      }
      if( hasArg ){
        zReturn = azArg[i+1];
      }else{
        zReturn = azArg[i];
      }
      j = i+1+(hasArg!=0);
      while( j<nArg ) azArg[i++] = azArg[j++];
      *pnArg = i;
      return zReturn;
    }
  }
  return zReturn;
}

/* Print a usage message for the program and exit */
static void usage(const char *argv0){
  int i;
  const char *zTail = argv0;
  for(i=0; argv0[i]; i++){
    if( argv0[i]=='/' ) zTail = argv0+i+1;
  }
  fprintf(stderr,"Usage: %s DATABASE ?OPTIONS? ?SCRIPT?\n", zTail);
  exit(1);
}

/* Report on unrecognized arguments */
static void unrecognizedArguments(
  const char *argv0,
  int nArg,
  char **azArg
){
  int i;
  fprintf(stderr,"%s: unrecognized arguments:", argv0);
  for(i=0; i<nArg; i++){
    fprintf(stderr," %s", azArg[i]);
  }
  fprintf(stderr,"\n");
  exit(1);
}

int main(int argc, char **argv){
  const char *zClient;
  int iClient;
  int n, i;
  int openFlags = SQLITE_OPEN_READWRITE;
  int rc;
  char *zScript;
  int taskId;
  const char *zTrace;
  const char *zCOption;

  g.argv0 = argv[0];
  g.iTrace = 1;
  if( argc<2 ) usage(argv[0]);
  g.zDbFile = argv[1];
  if( strglob("*.test", g.zDbFile) ) usage(argv[0]);
  if( strcmp(sqlite3_sourceid(), SQLITE_SOURCE_ID)!=0 ){
    fprintf(stderr, "SQLite library and header mismatch\n"
                    "Library: %s\n"
                    "Header:  %s\n",
                    sqlite3_sourceid(), SQLITE_SOURCE_ID);
    exit(1);
  }
  n = argc-2;
  sqlite3_snprintf(sizeof(g.zName), g.zName, "%05d.mptest", GETPID());
  g.zVfs = findOption(argv+2, &n, "vfs", 1);
  zClient = findOption(argv+2, &n, "client", 1);
  g.zErrLog = findOption(argv+2, &n, "errlog", 1);
  g.zLog = findOption(argv+2, &n, "log", 1);
  zTrace = findOption(argv+2, &n, "trace", 1);
  if( zTrace ) g.iTrace = atoi(zTrace);
  if( findOption(argv+2, &n, "quiet", 0)!=0 ) g.iTrace = 0;
  g.bSqlTrace = findOption(argv+2, &n, "sqltrace", 0)!=0;
  g.bSync = findOption(argv+2, &n, "sync", 0)!=0;
  if( g.zErrLog ){
    g.pErrLog = fopen(g.zErrLog, "a");
  }else{
    g.pErrLog = stderr;
  }
  if( g.zLog ){
    g.pLog = fopen(g.zLog, "a");
  }else{
    g.pLog = stdout;
  }
  
  sqlite3_config(SQLITE_CONFIG_LOG, sqlErrorCallback, 0);
  if( zClient ){
    iClient = atoi(zClient);
    if( iClient<1 ) fatalError("illegal client number: %d\n", iClient);
    sqlite3_snprintf(sizeof(g.zName), g.zName, "%05d.client%02d",
                     GETPID(), iClient);
  }else{
    if( g.iTrace>0 ){
      printf("With SQLite " SQLITE_VERSION " " SQLITE_SOURCE_ID "\n" );
      for(i=0; (zCOption = sqlite3_compileoption_get(i))!=0; i++){
        printf("-DSQLITE_%s\n", zCOption);
      }
      fflush(stdout);
    }
    iClient =  0;
    unlink(g.zDbFile);
    openFlags |= SQLITE_OPEN_CREATE;
  }
  rc = sqlite3_open_v2(g.zDbFile, &g.db, openFlags, g.zVfs);
  if( rc ) fatalError("cannot open [%s]", g.zDbFile);
  sqlite3_enable_load_extension(g.db, 1);
  sqlite3_busy_handler(g.db, busyHandler, 0);
  sqlite3_create_function(g.db, "vfsname", 0, SQLITE_UTF8, 0,
                          vfsNameFunc, 0, 0);
  sqlite3_create_function(g.db, "eval", 1, SQLITE_UTF8, 0,
                          evalFunc, 0, 0);
  g.iTimeout = DEFAULT_TIMEOUT;
  if( g.bSqlTrace ) sqlite3_trace(g.db, sqlTraceCallback, 0);
  if( !g.bSync ) trySql("PRAGMA synchronous=OFF");
  if( iClient>0 ){
    if( n>0 ) unrecognizedArguments(argv[0], n, argv+2);
    if( g.iTrace ) logMessage("start-client");
    while(1){
      char *zTaskName = 0;
      rc = startScript(iClient, &zScript, &taskId, &zTaskName);
      if( rc==SQLITE_DONE ) break;
      if( g.iTrace ) logMessage("begin %s (%d)", zTaskName, taskId);
      runScript(iClient, taskId, zScript, zTaskName);
      if( g.iTrace ) logMessage("end %s (%d)", zTaskName, taskId);
      finishScript(iClient, taskId, 0);
      sqlite3_free(zTaskName);
      sqlite3_sleep(10);
    }
    if( g.iTrace ) logMessage("end-client");
  }else{
    sqlite3_stmt *pStmt;
    int iTimeout;
    if( n==0 ){
      fatalError("missing script filename");
    }
    if( n>1 ) unrecognizedArguments(argv[0], n, argv+2);
    runSql(
      "CREATE TABLE task(\n"
      "  id INTEGER PRIMARY KEY,\n"
      "  name TEXT,\n"
      "  client INTEGER,\n"
      "  starttime DATE,\n"
      "  endtime DATE,\n"
      "  script TEXT\n"
      ");"
      "CREATE INDEX task_i1 ON task(client, starttime);\n"
      "CREATE INDEX task_i2 ON task(client, endtime);\n"
      "CREATE TABLE counters(nError,nTest);\n"
      "INSERT INTO counters VALUES(0,0);\n"
      "CREATE TABLE client(id INTEGER PRIMARY KEY, wantHalt);\n"
    );
    zScript = readFile(argv[2]);
    if( g.iTrace ) logMessage("begin script [%s]\n", argv[2]);
    runScript(0, 0, zScript, argv[2]);
    sqlite3_free(zScript);
    if( g.iTrace ) logMessage("end script [%s]\n", argv[2]);
    waitForClient(0, 2000, "during shutdown...\n");
    trySql("UPDATE client SET wantHalt=1");
    sqlite3_sleep(10);
    g.iTimeout = 0;
    iTimeout = 1000;
    while( ((rc = trySql("SELECT 1 FROM client"))==SQLITE_BUSY
        || rc==SQLITE_ROW) && iTimeout>0 ){
      sqlite3_sleep(10);
      iTimeout -= 10;
    }
    sqlite3_sleep(100);
    pStmt = prepareSql("SELECT nError, nTest FROM counters");
    iTimeout = 1000;
    while( (rc = sqlite3_step(pStmt))==SQLITE_BUSY && iTimeout>0 ){
      sqlite3_sleep(10);
      iTimeout -= 10;
    }
    if( rc==SQLITE_ROW ){
      g.nError += sqlite3_column_int(pStmt, 0);
      g.nTest += sqlite3_column_int(pStmt, 1);
    }
    sqlite3_finalize(pStmt);
  }
  sqlite3_close(g.db);  
  maybeClose(g.pLog);
  maybeClose(g.pErrLog);
  if( iClient==0 ){
    printf("Summary: %d errors in %d tests\n", g.nError, g.nTest);
  }
  return g.nError>0;
}