SQLite

USE_AMALGAMATION = @USE_AMALGAMATION@

# Object files for the SQLite library (non-amalgamation).
#
LIBOBJS0 = alter.lo analyze.lo attach.lo auth.lo \
         backup.lo bitvec.lo btmutex.lo btree.lo build.lo \
         callback.lo complete.lo ctime.lo date.lo dbstat.lo delete.lo \
         callback.lo complete.lo ctime.lo \
         date.lo dbpage.lo dbstat.lo delete.lo \
         expr.lo fault.lo fkey.lo \
         fts3.lo fts3_aux.lo fts3_expr.lo fts3_hash.lo fts3_icu.lo \
         fts3_porter.lo fts3_snippet.lo fts3_tokenizer.lo fts3_tokenizer1.lo \
         fts3_tokenize_vtab.lo \
         fts3_unicode.lo fts3_unicode2.lo fts3_write.lo \
	 fts5.lo \
         func.lo global.lo hash.lo \

  $(TOP)/src/btree.h \
  $(TOP)/src/btreeInt.h \
  $(TOP)/src/build.c \
  $(TOP)/src/callback.c \
  $(TOP)/src/complete.c \
  $(TOP)/src/ctime.c \
  $(TOP)/src/date.c \
  $(TOP)/src/dbpage.c \
  $(TOP)/src/dbstat.c \
  $(TOP)/src/delete.c \
  $(TOP)/src/expr.c \
  $(TOP)/src/fault.c \
  $(TOP)/src/fkey.c \
  $(TOP)/src/func.c \
  $(TOP)/src/global.c \

  $(TOP)/src/attach.c \
  $(TOP)/src/backup.c \
  $(TOP)/src/bitvec.c \
  $(TOP)/src/btree.c \
  $(TOP)/src/build.c \
  $(TOP)/src/ctime.c \
  $(TOP)/src/date.c \
  $(TOP)/src/dbpage.c \
  $(TOP)/src/dbstat.c \
  $(TOP)/src/expr.c \
  $(TOP)/src/func.c \
  $(TOP)/src/insert.c \
  $(TOP)/src/wal.c \
  $(TOP)/src/main.c \
  $(TOP)/src/mem5.c \

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

# This is the default Makefile target.  The objects listed here

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

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

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

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

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

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

###############################################################################

# <<mark>>
# Object files for the SQLite library (non-amalgamation).
#
LIBOBJS0 = vdbe.lo parse.lo alter.lo analyze.lo attach.lo auth.lo \
         backup.lo bitvec.lo btmutex.lo btree.lo build.lo \
         callback.lo complete.lo ctime.lo date.lo dbstat.lo delete.lo \
         callback.lo complete.lo ctime.lo \
         date.lo dbpage.lo dbstat.lo delete.lo \
         expr.lo fault.lo fkey.lo \
         fts3.lo fts3_aux.lo fts3_expr.lo fts3_hash.lo fts3_icu.lo \
         fts3_porter.lo fts3_snippet.lo fts3_tokenizer.lo fts3_tokenizer1.lo \
         fts3_tokenize_vtab.lo fts3_unicode.lo fts3_unicode2.lo fts3_write.lo \
         fts5.lo \
         func.lo global.lo hash.lo \
         icu.lo insert.lo legacy.lo loadext.lo \

  $(TOP)\src\btmutex.c \
  $(TOP)\src\btree.c \
  $(TOP)\src\build.c \
  $(TOP)\src\callback.c \
  $(TOP)\src\complete.c \
  $(TOP)\src\ctime.c \
  $(TOP)\src\date.c \
  $(TOP)\src\dbpage.c \
  $(TOP)\src\dbstat.c \
  $(TOP)\src\delete.c \
  $(TOP)\src\expr.c \
  $(TOP)\src\fault.c \
  $(TOP)\src\fkey.c \
  $(TOP)\src\func.c \
  $(TOP)\src\global.c \

# <</mark>>

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

# <<mark>>
# Extra compiler options for various test tools.
#
MPTESTER_COMPILE_OPTS = -DSQLITE_ENABLE_JSON1 -DSQLITE_ENABLE_FTS5
FUZZERSHELL_COMPILE_OPTS = -DSQLITE_ENABLE_JSON1

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

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

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

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

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

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

This folder contains extensions and utility programs intended to analyze
live database files, detect problems, and possibly fix them.

As SQLite is being used on larger and larger databases, database sizes
are growing into the terabyte range.  At that size, hardware malfunctions
and/or cosmic rays will occasionally corrupt a database file.  Detecting 
problems and fixing errors a terabyte-sized databases can take hours or days,
and it is undesirable to take applications that depend on the databases 
off-line for such a long time.
The utilities in the folder are intended to provide mechanisms for
detecting and fixing problems in large databases while those databases
are in active use.

The utilities and extensions in this folder are experimental and under
active development at the time of this writing (2017-10-12).  If and when
they stabilize, this README will be updated to reflect that fact.

/*
** 2017 October 11
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This module exports a single C function:
**
**   int sqlite3_check_freelist(sqlite3 *db, const char *zDb);
**
** This function checks the free-list in database zDb (one of "main", 
** "temp", etc.) and reports any errors by invoking the sqlite3_log()
** function. It returns SQLITE_OK if successful, or an SQLite error
** code otherwise. It is not an error if the free-list is corrupted but
** no IO or OOM errors occur.
**
** If this file is compiled and loaded as an SQLite loadable extension,
** it adds an SQL function "checkfreelist" to the database handle, to
** be invoked as follows:
**
**   SELECT checkfreelist(<database-name>);
**
** This function performs the same checks as sqlite3_check_freelist(),
** except that it returns all error messages as a single text value,
** separated by newline characters. If the freelist is not corrupted
** in any way, an empty string is returned.
**
** To compile this module for use as an SQLite loadable extension:
**
**   gcc -Os -fPIC -shared checkfreelist.c -o checkfreelist.so
*/

#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;
  typedef unsigned int u32;
#define get4byte(x) (        \
    ((u32)((x)[0])<<24) +    \
    ((u32)((x)[1])<<16) +    \
    ((u32)((x)[2])<<8) +     \
    ((u32)((x)[3]))          \
)
#endif

/*
** Execute a single PRAGMA statement and return the integer value returned
** via output parameter (*pnOut).
**
** The SQL statement passed as the third argument should be a printf-style
** format string containing a single "%s" which will be replace by the
** value passed as the second argument. e.g.
**
**   sqlGetInteger(db, "main", "PRAGMA %s.page_count", pnOut)
**
** executes "PRAGMA main.page_count" and stores the results in (*pnOut).
*/
static int sqlGetInteger(
  sqlite3 *db,                    /* Database handle */
  const char *zDb,                /* Database name ("main", "temp" etc.) */
  const char *zFmt,               /* SQL statement format */
  u32 *pnOut                      /* OUT: Integer value */
){
  int rc, rc2;
  char *zSql;
  sqlite3_stmt *pStmt = 0;
  int bOk = 0;

  zSql = sqlite3_mprintf(zFmt, zDb);
  if( zSql==0 ){
    rc = SQLITE_NOMEM;
  }else{
    rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0);
    sqlite3_free(zSql);
  }

  if( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pStmt) ){
    *pnOut = (u32)sqlite3_column_int(pStmt, 0);
    bOk = 1;
  }

  rc2 = sqlite3_finalize(pStmt);
  if( rc==SQLITE_OK ) rc = rc2;
  if( rc==SQLITE_OK && bOk==0 ) rc = SQLITE_ERROR;
  return rc;
}

/*
** Argument zFmt must be a printf-style format string and must be 
** followed by its required arguments. If argument pzOut is NULL, 
** then the results of printf()ing the format string are passed to
** sqlite3_log(). Otherwise, they are appended to the string
** at (*pzOut).
*/
static int checkFreelistError(char **pzOut, const char *zFmt, ...){
  int rc = SQLITE_OK;
  char *zErr = 0;
  va_list ap;

  va_start(ap, zFmt);
  zErr = sqlite3_vmprintf(zFmt, ap);
  if( zErr==0 ){
    rc = SQLITE_NOMEM;
  }else{
    if( pzOut ){
      *pzOut = sqlite3_mprintf("%s%z%s", *pzOut?"\n":"", *pzOut, zErr);
      if( *pzOut==0 ) rc = SQLITE_NOMEM;
    }else{
      sqlite3_log(SQLITE_ERROR, "checkfreelist: %s", zErr);
    }
    sqlite3_free(zErr);
  }
  va_end(ap);
  return rc;
}

static int checkFreelist(
  sqlite3 *db, 
  const char *zDb,
  char **pzOut
){
  /* This query returns one row for each page on the free list. Each row has
  ** two columns - the page number and page content.  */
  const char *zTrunk = 
    "WITH freelist_trunk(i, d, n) AS ("
      "SELECT 1, NULL, sqlite_readint32(data, 32) "
      "FROM sqlite_dbpage(:1) WHERE pgno=1 "
        "UNION ALL "
      "SELECT n, data, sqlite_readint32(data) "
      "FROM freelist_trunk, sqlite_dbpage(:1) WHERE pgno=n "
    ")"
    "SELECT i, d FROM freelist_trunk WHERE i!=1;";

  int rc, rc2;                    /* Return code */
  sqlite3_stmt *pTrunk = 0;       /* Compilation of zTrunk */
  u32 nPage = 0;                  /* Number of pages in db */
  u32 nExpected = 0;              /* Expected number of free pages */
  u32 nFree = 0;                  /* Number of pages on free list */

  if( zDb==0 ) zDb = "main";

  if( (rc = sqlGetInteger(db, zDb, "PRAGMA %s.page_count", &nPage))
   || (rc = sqlGetInteger(db, zDb, "PRAGMA %s.freelist_count", &nExpected))
  ){
    return rc;
  }

  rc = sqlite3_prepare_v2(db, zTrunk, -1, &pTrunk, 0);
  if( rc!=SQLITE_OK ) return rc;
  sqlite3_bind_text(pTrunk, 1, zDb, -1, SQLITE_STATIC);
  while( rc==SQLITE_OK && sqlite3_step(pTrunk)==SQLITE_ROW ){
    u32 i;
    u32 iTrunk = (u32)sqlite3_column_int(pTrunk, 0);
    const u8 *aData = (const u8*)sqlite3_column_blob(pTrunk, 1);
    int nData = sqlite3_column_bytes(pTrunk, 1);
    u32 iNext = get4byte(&aData[0]);
    u32 nLeaf = get4byte(&aData[4]);

    if( nLeaf>((nData/4)-2-6) ){
      rc = checkFreelistError(pzOut, 
          "leaf count out of range (%d) on trunk page %d", 
          (int)nLeaf, (int)iTrunk
      );
      nLeaf = (nData/4) - 2 - 6;
    }

    nFree += 1+nLeaf;
    if( iNext>nPage ){
      rc = checkFreelistError(pzOut, 
          "trunk page %d is out of range", (int)iNext
      );
    }

    for(i=0; rc==SQLITE_OK && i<nLeaf; i++){
      u32 iLeaf = get4byte(&aData[8 + 4*i]);
      if( iLeaf==0 || iLeaf>nPage ){
        rc = checkFreelistError(pzOut,
            "leaf page %d is out of range (child %d of trunk page %d)", 
            (int)iLeaf, (int)i, (int)iTrunk
        );
      }
    }
  }

  if( rc==SQLITE_OK && nFree!=nExpected ){
    rc = checkFreelistError(pzOut,
        "free-list count mismatch: actual=%d header=%d", 
        (int)nFree, (int)nExpected
    );
  }

  rc2 = sqlite3_finalize(pTrunk);
  if( rc==SQLITE_OK ) rc = rc2;
  return rc;
}

int sqlite3_check_freelist(sqlite3 *db, const char *zDb){
  return checkFreelist(db, zDb, 0);
}

static void checkfreelist_function(
  sqlite3_context *pCtx,
  int nArg,
  sqlite3_value **apArg
){
  const char *zDb;
  int rc;
  char *zOut = 0;
  sqlite3 *db = sqlite3_context_db_handle(pCtx);

  assert( nArg==1 );
  zDb = (const char*)sqlite3_value_text(apArg[0]);
  rc = checkFreelist(db, zDb, &zOut);
  if( rc==SQLITE_OK ){
    sqlite3_result_text(pCtx, zOut?zOut:"ok", -1, SQLITE_TRANSIENT);
  }else{
    sqlite3_result_error_code(pCtx, rc);
  }

  sqlite3_free(zOut);
}

/*
** An SQL function invoked as follows:
**
**   sqlite_readint32(BLOB)           -- Decode 32-bit integer from start of blob
*/
static void readint_function(
  sqlite3_context *pCtx,
  int nArg,
  sqlite3_value **apArg
){
  const u8 *zBlob;
  int nBlob;
  int iOff = 0;
  u32 iRet = 0;

  if( nArg!=1 && nArg!=2 ){
    sqlite3_result_error(
        pCtx, "wrong number of arguments to function sqlite_readint32()", -1
    );
    return;
  }
  if( nArg==2 ){
    iOff = sqlite3_value_int(apArg[1]);
  }

  zBlob = sqlite3_value_blob(apArg[0]);
  nBlob = sqlite3_value_bytes(apArg[0]);

  if( nBlob>=(iOff+4) ){
    iRet = get4byte(&zBlob[iOff]);
  }

  sqlite3_result_int64(pCtx, (sqlite3_int64)iRet);
}

/*
** Register the SQL functions.
*/
static int cflRegister(sqlite3 *db){
  int rc = sqlite3_create_function(
      db, "sqlite_readint32", -1, SQLITE_UTF8, 0, readint_function, 0, 0
  );
  if( rc!=SQLITE_OK ) return rc;
  rc = sqlite3_create_function(
      db, "checkfreelist", 1, SQLITE_UTF8, 0, checkfreelist_function, 0, 0
  );
  return rc;
}

/*
** Extension load function.
*/
#ifdef _WIN32
__declspec(dllexport)
#endif
int sqlite3_checkfreelist_init(
  sqlite3 *db, 
  char **pzErrMsg, 
  const sqlite3_api_routines *pApi
){
  SQLITE_EXTENSION_INIT2(pApi);
  return cflRegister(db);
}

THREADLIB += $(LIBS)

# Object files for the SQLite library.
#
LIBOBJ+= vdbe.o parse.o \
         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 dbstat.o delete.o expr.o \
         callback.o complete.o ctime.o \
         date.o dbpage.o dbstat.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 fts5.o func.o global.o hash.o \
         icu.o insert.o json1.o legacy.o loadext.o \

  $(TOP)/src/btree.h \
  $(TOP)/src/btreeInt.h \
  $(TOP)/src/build.c \
  $(TOP)/src/callback.c \
  $(TOP)/src/complete.c \
  $(TOP)/src/ctime.c \
  $(TOP)/src/date.c \
  $(TOP)/src/dbpage.c \
  $(TOP)/src/dbstat.c \
  $(TOP)/src/delete.c \
  $(TOP)/src/expr.c \
  $(TOP)/src/fault.c \
  $(TOP)/src/fkey.c \
  $(TOP)/src/func.c \
  $(TOP)/src/global.c \

TESTSRC2 = \
  $(TOP)/src/attach.c \
  $(TOP)/src/backup.c \
  $(TOP)/src/btree.c \
  $(TOP)/src/build.c \
  $(TOP)/src/date.c \
  $(TOP)/src/dbpage.c \
  $(TOP)/src/dbstat.c \
  $(TOP)/src/expr.c \
  $(TOP)/src/func.c \
  $(TOP)/src/insert.c \
  $(TOP)/src/wal.c \
  $(TOP)/src/main.c \
  $(TOP)/src/mem5.c \

# Extra compiler options for various shell tools
#
SHELL_OPT += -DSQLITE_ENABLE_JSON1 -DSQLITE_ENABLE_FTS4 -DSQLITE_ENABLE_FTS5
SHELL_OPT += -DSQLITE_ENABLE_EXPLAIN_COMMENTS
SHELL_OPT += -DSQLITE_ENABLE_UNKNOWN_SQL_FUNCTION
SHELL_OPT += -DSQLITE_ENABLE_STMTVTAB
SHELL_OPT += -DSQLITE_ENABLE_DBPAGE_VTAB
SHELL_OPT += -DSQLITE_ENABLE_DBSTAT_VTAB
FUZZERSHELL_OPT = -DSQLITE_ENABLE_JSON1
FUZZCHECK_OPT = -DSQLITE_ENABLE_JSON1 -DSQLITE_ENABLE_MEMSYS5
FUZZCHECK_OPT += -DSQLITE_MAX_MEMORY=50000000
DBFUZZ_OPT =
KV_OPT = -DSQLITE_THREADSAFE=0 -DSQLITE_DIRECT_OVERFLOW_READ
ST_OPT = -DSQLITE_THREADSAFE=0

/*
** 2017-10-11
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
******************************************************************************
**
** This file contains an implementation of the "sqlite_dbpage" virtual table.
**
** The sqlite_dbpage virtual table is used to read or write whole raw
** pages of the database file.  The pager interface is used so that 
** uncommitted changes and changes recorded in the WAL file are correctly
** retrieved.
**
** Usage example:
**
**    SELECT data FROM sqlite_dbpage('aux1') WHERE pgno=123;
**
** This is an eponymous virtual table so it does not need to be created before
** use.  The optional argument to the sqlite_dbpage() table name is the
** schema for the database file that is to be read.  The default schema is
** "main".
**
** The data field of sqlite_dbpage table can be updated.  The new
** value must be a BLOB which is the correct page size, otherwise the
** update fails.  Rows may not be deleted or inserted.
*/

#include "sqliteInt.h"   /* Requires access to internal data structures */
#if (defined(SQLITE_ENABLE_DBPAGE_VTAB) || defined(SQLITE_TEST)) \
    && !defined(SQLITE_OMIT_VIRTUALTABLE)

typedef struct DbpageTable DbpageTable;
typedef struct DbpageCursor DbpageCursor;

struct DbpageCursor {
  sqlite3_vtab_cursor base;       /* Base class.  Must be first */
  int pgno;                       /* Current page number */
  int mxPgno;                     /* Last page to visit on this scan */
};

struct DbpageTable {
  sqlite3_vtab base;              /* Base class.  Must be first */
  sqlite3 *db;                    /* The database */
  Pager *pPager;                  /* Pager being read/written */
  int iDb;                        /* Index of database to analyze */
  int szPage;                     /* Size of each page in bytes */
  int nPage;                      /* Number of pages in the file */
};

/*
** Connect to or create a dbpagevfs virtual table.
*/
static int dbpageConnect(
  sqlite3 *db,
  void *pAux,
  int argc, const char *const*argv,
  sqlite3_vtab **ppVtab,
  char **pzErr
){
  DbpageTable *pTab = 0;
  int rc = SQLITE_OK;
  int iDb;

  if( argc>=4 ){
    Token nm;
    sqlite3TokenInit(&nm, (char*)argv[3]);
    iDb = sqlite3FindDb(db, &nm);
    if( iDb<0 ){
      *pzErr = sqlite3_mprintf("no such schema: %s", argv[3]);
      return SQLITE_ERROR;
    }
  }else{
    iDb = 0;
  }
  rc = sqlite3_declare_vtab(db, 
          "CREATE TABLE x(pgno INTEGER PRIMARY KEY, data BLOB, schema HIDDEN)");
  if( rc==SQLITE_OK ){
    pTab = (DbpageTable *)sqlite3_malloc64(sizeof(DbpageTable));
    if( pTab==0 ) rc = SQLITE_NOMEM_BKPT;
  }

  assert( rc==SQLITE_OK || pTab==0 );
  if( rc==SQLITE_OK ){
    Btree *pBt = db->aDb[iDb].pBt;
    memset(pTab, 0, sizeof(DbpageTable));
    pTab->db = db;
    pTab->iDb = iDb;
    pTab->pPager = pBt ? sqlite3BtreePager(pBt) : 0;
  }

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

/*
** Disconnect from or destroy a dbpagevfs virtual table.
*/
static int dbpageDisconnect(sqlite3_vtab *pVtab){
  sqlite3_free(pVtab);
  return SQLITE_OK;
}

/*
** idxNum:
**
**     0     full table scan
**     1     pgno=?1
*/
static int dbpageBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
  int i;
  pIdxInfo->estimatedCost = 1.0e6;  /* Initial cost estimate */
  for(i=0; i<pIdxInfo->nConstraint; i++){
    struct sqlite3_index_constraint *p = &pIdxInfo->aConstraint[i];
    if( p->usable && p->iColumn<=0 && p->op==SQLITE_INDEX_CONSTRAINT_EQ ){
      pIdxInfo->estimatedRows = 1;
      pIdxInfo->idxFlags = SQLITE_INDEX_SCAN_UNIQUE;
      pIdxInfo->estimatedCost = 1.0;
      pIdxInfo->idxNum = 1;
      pIdxInfo->aConstraintUsage[i].argvIndex = 1;
      pIdxInfo->aConstraintUsage[i].omit = 1;
      break;
    }
  }
  if( pIdxInfo->nOrderBy>=1
   && pIdxInfo->aOrderBy[0].iColumn<=0
   && pIdxInfo->aOrderBy[0].desc==0
  ){
    pIdxInfo->orderByConsumed = 1;
  }
  return SQLITE_OK;
}

/*
** Open a new dbpagevfs cursor.
*/
static int dbpageOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
  DbpageCursor *pCsr;

  pCsr = (DbpageCursor *)sqlite3_malloc64(sizeof(DbpageCursor));
  if( pCsr==0 ){
    return SQLITE_NOMEM_BKPT;
  }else{
    memset(pCsr, 0, sizeof(DbpageCursor));
    pCsr->base.pVtab = pVTab;
    pCsr->pgno = -1;
  }

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

/*
** Close a dbpagevfs cursor.
*/
static int dbpageClose(sqlite3_vtab_cursor *pCursor){
  DbpageCursor *pCsr = (DbpageCursor *)pCursor;
  sqlite3_free(pCsr);
  return SQLITE_OK;
}

/*
** Move a dbpagevfs cursor to the next entry in the file.
*/
static int dbpageNext(sqlite3_vtab_cursor *pCursor){
  int rc = SQLITE_OK;
  DbpageCursor *pCsr = (DbpageCursor *)pCursor;
  pCsr->pgno++;
  return rc;
}

static int dbpageEof(sqlite3_vtab_cursor *pCursor){
  DbpageCursor *pCsr = (DbpageCursor *)pCursor;
  return pCsr->pgno > pCsr->mxPgno;
}

static int dbpageFilter(
  sqlite3_vtab_cursor *pCursor, 
  int idxNum, const char *idxStr,
  int argc, sqlite3_value **argv
){
  DbpageCursor *pCsr = (DbpageCursor *)pCursor;
  DbpageTable *pTab = (DbpageTable *)pCursor->pVtab;
  int rc = SQLITE_OK;
  Btree *pBt = pTab->db->aDb[pTab->iDb].pBt;

  pTab->szPage = sqlite3BtreeGetPageSize(pBt);
  pTab->nPage = sqlite3BtreeLastPage(pBt);
  if( idxNum==1 ){
    pCsr->pgno = sqlite3_value_int(argv[0]);
    if( pCsr->pgno<1 || pCsr->pgno>pTab->nPage ){
      pCsr->pgno = 1;
      pCsr->mxPgno = 0;
    }else{
      pCsr->mxPgno = pCsr->pgno;
    }
  }else{
    pCsr->pgno = 1;
    pCsr->mxPgno = pTab->nPage;
  }
  return rc;
}

static int dbpageColumn(
  sqlite3_vtab_cursor *pCursor, 
  sqlite3_context *ctx, 
  int i
){
  DbpageCursor *pCsr = (DbpageCursor *)pCursor;
  DbpageTable *pTab = (DbpageTable *)pCursor->pVtab;
  int rc = SQLITE_OK;
  switch( i ){
    case 0: {           /* pgno */
      sqlite3_result_int(ctx, pCsr->pgno);
      break;
    }
    case 1: {           /* data */
      DbPage *pDbPage = 0;
      rc = sqlite3PagerGet(pTab->pPager, pCsr->pgno, (DbPage**)&pDbPage, 0);
      if( rc==SQLITE_OK ){
        sqlite3_result_blob(ctx, sqlite3PagerGetData(pDbPage), pTab->szPage,
                            SQLITE_TRANSIENT);
      }
      sqlite3PagerUnref(pDbPage);
      break;
    }
    default: {          /* schema */
      sqlite3 *db = sqlite3_context_db_handle(ctx);
      sqlite3_result_text(ctx, db->aDb[pTab->iDb].zDbSName, -1, SQLITE_STATIC);
      break;
    }
  }
  return SQLITE_OK;
}

static int dbpageRowid(sqlite3_vtab_cursor *pCursor, sqlite_int64 *pRowid){
  DbpageCursor *pCsr = (DbpageCursor *)pCursor;
  *pRowid = pCsr->pgno;
  return SQLITE_OK;
}

static int dbpageUpdate(
  sqlite3_vtab *pVtab,
  int argc,
  sqlite3_value **argv,
  sqlite_int64 *pRowid
){
  DbpageTable *pTab = (DbpageTable *)pVtab;
  int pgno;
  DbPage *pDbPage = 0;
  int rc = SQLITE_OK;
  char *zErr = 0;

  if( argc==1 ){
    zErr = "cannot delete";
    goto update_fail;
  }
  pgno = sqlite3_value_int(argv[0]);
  if( pgno<1 || pgno>pTab->nPage ){
    zErr = "bad page number";
    goto update_fail;
  }
  if( sqlite3_value_int(argv[1])!=pgno ){
    zErr = "cannot insert";
    goto update_fail;
  }
  if( sqlite3_value_type(argv[3])!=SQLITE_BLOB 
   || sqlite3_value_bytes(argv[3])!=pTab->szPage 
  ){
    zErr = "bad page value";
    goto update_fail;
  }
  rc = sqlite3PagerGet(pTab->pPager, pgno, (DbPage**)&pDbPage, 0);
  if( rc==SQLITE_OK ){
    rc = sqlite3PagerWrite(pDbPage);
    if( rc==SQLITE_OK ){
      memcpy(sqlite3PagerGetData(pDbPage),
             sqlite3_value_blob(argv[3]),
             pTab->szPage);
    }
  }
  sqlite3PagerUnref(pDbPage);
  return rc;

update_fail:
  sqlite3_free(pVtab->zErrMsg);
  pVtab->zErrMsg = sqlite3_mprintf("%s", zErr);
  return SQLITE_ERROR;
}

/*
** Invoke this routine to register the "dbpage" virtual table module
*/
int sqlite3DbpageRegister(sqlite3 *db){
  static sqlite3_module dbpage_module = {
    0,                            /* iVersion */
    dbpageConnect,                /* xCreate */
    dbpageConnect,                /* xConnect */
    dbpageBestIndex,              /* xBestIndex */
    dbpageDisconnect,             /* xDisconnect */
    dbpageDisconnect,             /* xDestroy */
    dbpageOpen,                   /* xOpen - open a cursor */
    dbpageClose,                  /* xClose - close a cursor */
    dbpageFilter,                 /* xFilter - configure scan constraints */
    dbpageNext,                   /* xNext - advance a cursor */
    dbpageEof,                    /* xEof - check for end of scan */
    dbpageColumn,                 /* xColumn - read data */
    dbpageRowid,                  /* xRowid - read data */
    dbpageUpdate,                 /* xUpdate */
    0,                            /* xBegin */
    0,                            /* xSync */
    0,                            /* xCommit */
    0,                            /* xRollback */
    0,                            /* xFindMethod */
    0,                            /* xRename */
    0,                            /* xSavepoint */
    0,                            /* xRelease */
    0,                            /* xRollbackTo */
  };
  return sqlite3_create_module(db, "sqlite_dbpage", &dbpage_module, 0);
}
#elif defined(SQLITE_ENABLE_DBPAGE_VTAB)
int sqlite3DbpageRegister(sqlite3 *db){ return SQLITE_OK; }
#endif /* SQLITE_ENABLE_DBSTAT_VTAB */

#endif

#ifdef SQLITE_ENABLE_RTREE
  if( !db->mallocFailed && rc==SQLITE_OK){
    rc = sqlite3RtreeInit(db);
  }
#endif

#ifdef SQLITE_ENABLE_DBPAGE_VTAB
  if( !db->mallocFailed && rc==SQLITE_OK){
    rc = sqlite3DbpageRegister(db);
  }
#endif

#ifdef SQLITE_ENABLE_DBSTAT_VTAB
  if( !db->mallocFailed && rc==SQLITE_OK){
    rc = sqlite3DbstatRegister(db);
  }
#endif

     { "number of triggers:",
       "SELECT count(*) FROM %s WHERE type='trigger'" },
     { "number of views:",
       "SELECT count(*) FROM %s WHERE type='view'" },
     { "schema size:",
       "SELECT total(length(sql)) FROM %s" },
  };
  sqlite3_file *pFile = 0;
  int i;
  char *zSchemaTab;
  char *zDb = nArg>=2 ? azArg[1] : "main";
  sqlite3_stmt *pStmt = 0;
  unsigned char aHdr[100];
  open_db(p, 0);
  if( p->db==0 ) return 1;
  sqlite3_file_control(p->db, zDb, SQLITE_FCNTL_FILE_POINTER, &pFile);
  if( pFile==0 || pFile->pMethods==0 || pFile->pMethods->xRead==0 ){
    return 1;
  }
  sqlite3_prepare_v2(p->db,"SELECT data FROM sqlite_dbpage(?1) WHERE pgno=1",
                     -1, &pStmt, 0);
  sqlite3_bind_text(pStmt, 1, zDb, -1, SQLITE_STATIC);
  if( sqlite3_step(pStmt)==SQLITE_ROW
   && sqlite3_column_bytes(pStmt,0)>100
  ){
    memcpy(aHdr, sqlite3_column_blob(pStmt,0), 100);
    sqlite3_finalize(pStmt);
  }else{
  i = pFile->pMethods->xRead(pFile, aHdr, 100, 0);
  if( i!=SQLITE_OK ){
    raw_printf(stderr, "unable to read database header\n");
    sqlite3_finalize(pStmt);
    return 1;
  }
  i = get2byteInt(aHdr+16);
  if( i==1 ) i = 65536;
  utf8_printf(p->out, "%-20s %d\n", "database page size:", i);
  utf8_printf(p->out, "%-20s %d\n", "write format:", aHdr[18]);
  utf8_printf(p->out, "%-20s %d\n", "read format:", aHdr[19]);

** Threading interface
*/
#if SQLITE_MAX_WORKER_THREADS>0
int sqlite3ThreadCreate(SQLiteThread**,void*(*)(void*),void*);
int sqlite3ThreadJoin(SQLiteThread*, void**);
#endif

#if defined(SQLITE_ENABLE_DBPAGE_VTAB) || defined(SQLITE_TEST)
int sqlite3DbpageRegister(sqlite3*);
#endif
#if defined(SQLITE_ENABLE_DBSTAT_VTAB) || defined(SQLITE_TEST)
int sqlite3DbstatRegister(sqlite3*);
#endif

int sqlite3ExprVectorSize(Expr *pExpr);
int sqlite3ExprIsVector(Expr *pExpr);
Expr *sqlite3VectorFieldSubexpr(Expr*, int);

# 2017-10-11
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this file is testing the checkfreelist extension.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix checkfreelist

ifcapable !vtab||!compound {
  finish_test
  return
}

if {[file exists ../checkfreelist.so]==0} {
  finish_test
  return
}

do_execsql_test 1.0 {
  CREATE TABLE t1(a, b);
}

db enable_load_extension 1
do_execsql_test 1.1 {
  SELECT load_extension('../checkfreelist.so');
} {{}}

do_execsql_test 1.2 { SELECT checkfreelist('main') } {ok}
do_execsql_test 1.3 {
  WITH s(i) AS (
    SELECT 1 UNION ALL SELECT i+1 FROM s WHERE i<10000
  )
  INSERT INTO t1 SELECT randomblob(400), randomblob(400) FROM s;
  DELETE FROM t1 WHERE rowid%3;
  PRAGMA freelist_count;
} {6726}

do_execsql_test 1.4 { SELECT checkfreelist('main') } {ok}
do_execsql_test 1.5 {
  WITH freelist_trunk(i, d, n) AS (
    SELECT 1, NULL, sqlite_readint32(data, 32) FROM sqlite_dbpage WHERE pgno=1
      UNION ALL
    SELECT n, data, sqlite_readint32(data) 
    FROM freelist_trunk, sqlite_dbpage WHERE pgno=n
  )
  SELECT i FROM freelist_trunk WHERE i!=1;
} {
  10010 9716 9344 8970 8596 8223 7848 7475 7103 6728 6355 5983 5609 5235
  4861 4488 4113 3741 3368 2993 2620 2248 1873 1500 1126 753 378 5
}

do_execsql_test 1.6 { SELECT checkfreelist('main') } {ok}

proc set_int {blob idx newval} {
  binary scan $blob I* ints
  lset ints $idx $newval
  binary format I* $ints
}
db func set_int set_int

proc get_int {blob idx} {
  binary scan $blob I* ints
  lindex $ints $idx
}
db func get_int get_int

do_execsql_test 1.7 {
  BEGIN;
    UPDATE sqlite_dbpage 
      SET data = set_int(data, 1, get_int(data, 1)-1) 
      WHERE pgno=4861;
    SELECT checkfreelist('main');
  ROLLBACK;
} {{free-list count mismatch: actual=6725 header=6726}}

do_execsql_test 1.8 {
  BEGIN;
    UPDATE sqlite_dbpage 
      SET data = set_int(data, 5, (SELECT * FROM pragma_page_count)+1)
      WHERE pgno=4861;
    SELECT checkfreelist('main');
  ROLLBACK;
} {{leaf page 10093 is out of range (child 3 of trunk page 4861)}}

do_execsql_test 1.9 {
  BEGIN;
    UPDATE sqlite_dbpage 
      SET data = set_int(data, 5, 0)
      WHERE pgno=4861;
    SELECT checkfreelist('main');
  ROLLBACK;
} {{leaf page 0 is out of range (child 3 of trunk page 4861)}}

do_execsql_test 1.10 {
  BEGIN;
    UPDATE sqlite_dbpage 
      SET data = set_int(data, get_int(data, 1)+1, 0)
      WHERE pgno=5;
    SELECT checkfreelist('main');
  ROLLBACK;
} {{leaf page 0 is out of range (child 247 of trunk page 5)}}

do_execsql_test 1.11 {
  BEGIN;
    UPDATE sqlite_dbpage 
      SET data = set_int(data, 1, 249)
      WHERE pgno=5;
    SELECT checkfreelist('main');
  ROLLBACK;
} {{leaf count out of range (249) on trunk page 5}}

finish_test

# 2017-10-11
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
# This file implements regression tests for SQLite library.  The
# focus of this file is testing the sqlite_dbpage virtual table.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix dbpage

ifcapable !vtab||!compound {
  finish_test
  return
}

do_execsql_test 100 {
  PRAGMA page_size=4096;
  PRAGMA journal_mode=WAL;
  CREATE TABLE t1(a,b);
  WITH RECURSIVE c(x) AS (VALUES(1) UNION ALL SELECT x+1 FROM c WHERE x<100)
  INSERT INTO t1(a,b) SELECT x, printf('%d-x%.*c',x,x,'x') FROM c;
  PRAGMA integrity_check;
} {wal ok}
do_execsql_test 110 {
  SELECT pgno, quote(substr(data,1,5)) FROM sqlite_dbpage('main') ORDER BY pgno;
} {1 X'53514C6974' 2 X'0500000001' 3 X'0D0000004E' 4 X'0D00000016'}
do_execsql_test 120 {
  SELECT pgno, quote(substr(data,1,5)) FROM sqlite_dbpage WHERE pgno=2;
} {2 X'0500000001'}
do_execsql_test 130 {
  SELECT pgno, quote(substr(data,1,5)) FROM sqlite_dbpage WHERE pgno=4;
} {4 X'0D00000016'}
do_execsql_test 140 {
  SELECT pgno, quote(substr(data,1,5)) FROM sqlite_dbpage WHERE pgno=5;
} {}
do_execsql_test 150 {
  SELECT pgno, quote(substr(data,1,5)) FROM sqlite_dbpage WHERE pgno=0;
} {}

do_execsql_test 200 {
  CREATE TEMP TABLE saved_content(x);
  INSERT INTO saved_content(x) SELECT data FROM sqlite_dbpage WHERE pgno=4;
  UPDATE sqlite_dbpage SET data=zeroblob(4096) WHERE pgno=4;
} {}
do_catchsql_test 210 {
  PRAGMA integrity_check;
} {1 {database disk image is malformed}}
do_execsql_test 220 {
  SELECT pgno, quote(substr(data,1,5)) FROM sqlite_dbpage('main') ORDER BY pgno;
} {1 X'53514C6974' 2 X'0500000001' 3 X'0D0000004E' 4 X'0000000000'}
do_execsql_test 230 {
  UPDATE sqlite_dbpage SET data=(SELECT x FROM saved_content) WHERE pgno=4;
} {}
do_catchsql_test 230 {
  PRAGMA integrity_check;
} {0 ok}




finish_test

   fts3_unicode2.c

   rtree.c
   icu.c
   fts3_icu.c
   sqlite3rbu.c
   dbstat.c
   dbpage.c
   sqlite3session.c
   json1.c
   fts5.c
   stmt.c
} {
  copy_file tsrc/$file
}