SQLite

/*
** 2004 April 6
**
** 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.
**
*************************************************************************
** $Id: btree.c,v 1.478 2008/07/11 03:38:41 drh Exp $
**
** This file implements a external (disk-based) database using BTrees.
** See the header comment on "btreeInt.h" for additional information.
** Including a description of file format and an overview of operation.
*/
#include "btreeInt.h"

  unsigned char *data = pPage->aData;

  assert( pPage->pBt!=0 );
  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
  assert( start>=pPage->hdrOffset+6+(pPage->leaf?0:4) );
  assert( (start + size)<=pPage->pBt->usableSize );
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  if( size<4 ) size = 4;

#ifdef SQLITE_SECURE_DELETE
  /* Overwrite deleted information with zeros when the SECURE_DELETE 
  ** option is enabled at compile-time */
  memset(&data[start], 0, size);
#endif

  p->db = db;

#if !defined(SQLITE_OMIT_SHARED_CACHE) && !defined(SQLITE_OMIT_DISKIO)
  /*
  ** If this Btree is a candidate for shared cache, try to find an
  ** existing BtShared object that we can share with
  */
  if( (flags & BTREE_PRIVATE)==0
   && isMemdb==0
   && (db->flags & SQLITE_Vtab)==0
   && zFilename && zFilename[0]
  ){
    if( sqlite3SharedCacheEnabled ){
      int nFullPathname = pVfs->mxPathname+1;
      char *zFullPathname = sqlite3Malloc(nFullPathname);
      sqlite3_mutex *mutexShared;
      p->sharable = 1;
      if( db ){
        db->flags |= SQLITE_SharedCache;
      }
      if( !zFullPathname ){
        sqlite3_free(p);
        return SQLITE_NOMEM;
      }
      sqlite3OsFullPathname(pVfs, zFilename, nFullPathname, zFullPathname);
      mutexShared = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
      sqlite3_mutex_enter(mutexShared);

  sqlite3_mutex_enter(pMaster);
  pBt->nRef--;
  if( pBt->nRef<=0 ){
    if( sqlite3SharedCacheList==pBt ){
      sqlite3SharedCacheList = pBt->pNext;
    }else{
      pList = sqlite3SharedCacheList;
      while( pList && pList->pNext!=pBt ){
        pList=pList->pNext;
      }
      if( pList ){
        pList->pNext = pBt->pNext;
      }
    }
    if( SQLITE_THREADSAFE ){
      sqlite3_mutex_free(pBt->mutex);
    }
    removed = 1;

**    May you share freely, never taking more than you give.
**
*************************************************************************
** This header file defines the interface that the sqlite B-Tree file
** subsystem.  See comments in the source code for a detailed description
** of what each interface routine does.
**
** @(#) $Id: btree.h,v 1.100 2008/07/10 00:32:42 drh Exp $
*/
#ifndef _BTREE_H_
#define _BTREE_H_

/* TODO: This definition is just included so other modules compile. It
** needs to be revisited.
*/

#define BTREE_OMIT_JOURNAL  1  /* Do not use journal.  No argument */
#define BTREE_NO_READLOCK   2  /* Omit readlocks on readonly files */
#define BTREE_MEMORY        4  /* In-memory DB.  No argument */
#define BTREE_READONLY      8  /* Open the database in read-only mode */
#define BTREE_READWRITE    16  /* Open for both reading and writing */
#define BTREE_CREATE       32  /* Create the database if it does not exist */

/* Additional values for the 4th argument of sqlite3BtreeOpen that
** are not associated with PAGER_ values.
*/
#define BTREE_PRIVATE      64  /* Never share with other connections */

int sqlite3BtreeClose(Btree*);
int sqlite3BtreeSetCacheSize(Btree*,int);
int sqlite3BtreeSetSafetyLevel(Btree*,int,int);
int sqlite3BtreeSyncDisabled(Btree*);
int sqlite3BtreeSetPageSize(Btree*,int,int);
int sqlite3BtreeGetPageSize(Btree*);
int sqlite3BtreeMaxPageCount(Btree*,int);

**
*************************************************************************
** Main file for the SQLite library.  The routines in this file
** implement the programmer interface to the library.  Routines in
** other files are for internal use by SQLite and should not be
** accessed by users of the library.
**
** $Id: main.c,v 1.475 2008/07/10 18:13:42 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

#ifdef SQLITE_ENABLE_FTS3
# include "fts3.h"
#endif

**
** This routine is called when an operation failed with a lock.
** If this routine returns non-zero, the lock is retried.  If it
** returns 0, the operation aborts with an SQLITE_BUSY error.
*/
int sqlite3InvokeBusyHandler(BusyHandler *p){
  int rc;
  failsafe( p==0, 0x912aaf8d, {return 0;})
  if( p->xFunc==0 || p->nBusy<0 ) return 0;
  rc = p->xFunc(p->pArg, p->nBusy);
  if( rc==0 ){
    p->nBusy = -1;
  }else{
    p->nBusy++;
  }
  return rc; 

** on how SQLite interfaces are suppose to operate.
**
** The name of this file under configuration management is "sqlite.h.in".
** The makefile makes some minor changes to this file (such as inserting
** the version number) and changes its name to "sqlite3.h" as
** part of the build process.
**
** @(#) $Id: sqlite.h.in,v 1.367 2008/07/10 18:13:42 drh Exp $
*/
#ifndef _SQLITE3_H_
#define _SQLITE3_H_
#include <stdarg.h>     /* Needed for the definition of va_list */

/*
** Make sure we can call this stuff from C++.

*/
#define SQLITE_STATUS_MEMORY_USED          0
#define SQLITE_STATUS_PAGECACHE_USED       1
#define SQLITE_STATUS_PAGECACHE_OVERFLOW   2
#define SQLITE_STATUS_SCRATCH_USED         3
#define SQLITE_STATUS_SCRATCH_OVERFLOW     4
#define SQLITE_STATUS_MALLOC_SIZE          5
#define SQLITE_STATUS_FAILSAFE             6


/*
** Undo the hack that converts floating point types to integer for
** builds on processors without floating point support.
*/
#ifdef SQLITE_OMIT_FLOATING_POINT

/*
** 2001 September 15
**
** 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.
**
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.740 2008/07/10 00:32:42 drh Exp $
*/
#ifndef _SQLITEINT_H_
#define _SQLITEINT_H_

/*
** Include the configuration header output by 'configure' if we're using the
** autoconf-based build

  void sqlite3Coverage(int);
# define testcase(X)  if( X ){ sqlite3Coverage(__LINE__); }
#else
# define testcase(X)
#endif

/*
** The failsafe() macro is used to test for error conditions that
** should never occur.  This is similar to assert() except that with
** failsafe() the application attempts to recover gracefully rather
** than abort.  If a error condition is detected, a global flag is
** set to the "Id" prior to recovery in order to alert the application 


** to the error condition.
**
** The Id should be a random integer.  The idea behind the Id is that
** failsafe() faults in the field can be mapped back to specific failsafe()
** macros, even if line numbers and filenames have changed.
**
** The test condition is argument Cond.  The recovery action is
** argument Action.
*/
#ifdef SQLITE_COVERAGE_TEST
# define failsafe(Cond,Id,Action)

#else
# define failsafe(Cond,Id,Action)  if( Cond ){ sqlite3Failsafe(Id); Action; }

#endif

/*
** The macro unlikely() is a hint that surrounds a boolean
** expression that is usually false.  Macro likely() surrounds
** a boolean expression that is usually true.  GCC is able to
** use these hints to generate better code, sometimes.

** This structure also contains some state information.
*/
struct Sqlite3Config {
  int bMemstat;                     /* True to enable memory status */
  int bCoreMutex;                   /* True to enable core mutexing */
  int bFullMutex;                   /* True to enable full mutexing */
  int mxStrlen;                     /* Maximum string length */
  int iFailsafe;                    /* Id of failed failsafe() */
  sqlite3_mem_methods m;            /* Low-level memory allocation interface */
  sqlite3_mutex_methods mutex;      /* Low-level mutex interface */
  void *pHeap;                      /* Heap storage space */
  int nHeap;                        /* Size of pHeap[] */
  int mnReq, mxReq;                 /* Min and max heap requests sizes */
  void *pScratch;                   /* Scratch memory */
  int szScratch;                    /* Size of each scratch buffer */

  int sqlite3SafetyOff(sqlite3*);
#else
# define sqlite3SafetyOn(A) 0
# define sqlite3SafetyOff(A) 0
#endif
int sqlite3SafetyCheckOk(sqlite3*);
int sqlite3SafetyCheckSickOrOk(sqlite3*);
void sqlite3Failsafe(int);
void sqlite3ChangeCookie(Parse*, int);
void sqlite3MaterializeView(Parse*, Select*, Expr*, int);

#ifndef SQLITE_OMIT_TRIGGER
  void sqlite3BeginTrigger(Parse*, Token*,Token*,int,int,IdList*,SrcList*,
                           Expr*,int, int);
  void sqlite3FinishTrigger(Parse*, TriggerStep*, Token*);

**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This module implements the sqlite3_status() interface and related
** functionality.
**
** $Id: status.c,v 1.2 2008/07/09 13:28:54 drh Exp $
*/
#include "sqliteInt.h"

/*
** Variables in which to record status information.
*/
static struct {

** Query status information.
**
** This implementation assumes that reading or writing an aligned
** 32-bit integer is an atomic operation.  If that assumption is not true,
** then this routine is not threadsafe.
*/
int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag){
  if( op==SQLITE_STATUS_FAILSAFE ){
    *pCurrent = *pHighwater = sqlite3Config.iFailsafe;
    if( resetFlag ) sqlite3Config.iFailsafe = 0;
    return SQLITE_OK;
  }
  if( op<0 || op>=ArraySize(sqlite3Stat.nowValue) ){
    return SQLITE_MISUSE;
  }
  *pCurrent = sqlite3Stat.nowValue[op];
  *pHighwater = sqlite3Stat.mxValue[op];
  if( resetFlag ){
    sqlite3Stat.mxValue[op] = sqlite3Stat.nowValue[op];
  }
  return SQLITE_OK;
}

**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This file contains code used to implement test interfaces to the
** memory allocation subsystem.
**
** $Id: test_malloc.c,v 1.36 2008/07/10 18:13:42 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>
#include <assert.h>

  } aOp[] = {
    { "SQLITE_STATUS_MEMORY_USED",         SQLITE_STATUS_MEMORY_USED         },
    { "SQLITE_STATUS_PAGECACHE_USED",      SQLITE_STATUS_PAGECACHE_USED      },
    { "SQLITE_STATUS_PAGECACHE_OVERFLOW",  SQLITE_STATUS_PAGECACHE_OVERFLOW  },
    { "SQLITE_STATUS_SCRATCH_USED",        SQLITE_STATUS_SCRATCH_USED        },
    { "SQLITE_STATUS_SCRATCH_OVERFLOW",    SQLITE_STATUS_SCRATCH_OVERFLOW    },
    { "SQLITE_STATUS_MALLOC_SIZE",         SQLITE_STATUS_MALLOC_SIZE         },
    { "SQLITE_STATUS_FAILSAFE",            SQLITE_STATUS_FAILSAFE            },
  };
  Tcl_Obj *pResult;
  if( objc!=3 ){
    Tcl_WrongNumArgs(interp, 1, objv, "PARAMETER RESETFLAG");
    return TCL_ERROR;
  }
  zOpName = Tcl_GetString(objv[1]);

**
*************************************************************************
** Utility functions used throughout sqlite.
**
** This file contains functions for allocating memory, comparing
** strings, and stuff like that.
**
** $Id: util.c,v 1.236 2008/07/10 00:32:42 drh Exp $
*/
#include "sqliteInt.h"
#include <stdarg.h>
#include <ctype.h>


/*

  if( db==0 ) return 0;
  magic = db->magic;
  if( magic!=SQLITE_MAGIC_SICK &&
      magic!=SQLITE_MAGIC_OPEN &&
      magic!=SQLITE_MAGIC_BUSY ) return 0;
  return 1;
}

#ifndef SQLITE_COVERAGE_TEST
/*
** Report a failsafe() macro failure
*/
void sqlite3Failsafe(int iCode){
  sqlite3Config.iFailsafe = iCode;

  /* The following assert is always false.  When assert() is enabled,
  ** the following causes a failsafe() failure to work like an assert()
  ** failure.  Normal operating mode for SQLite is for assert() to be
  ** disabled, however, so the following is normally a no-op.
  */
  assert( iCode==0 );   /* Always fails if assert() is enabled */
}
#endif

**
*************************************************************************
** This file contains code used for creating, destroying, and populating
** a VDBE (or an "sqlite3_stmt" as it is known to the outside world.)  Prior
** to version 2.8.7, all this code was combined into the vdbe.c source file.
** But that file was getting too big so this subroutines were split out.
**
** $Id: vdbeaux.c,v 1.395 2008/07/08 22:28:49 shane Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
#include "vdbeInt.h"

** Close a VDBE cursor and release all the resources that cursor 
** happens to hold.
*/
void sqlite3VdbeFreeCursor(Vdbe *p, Cursor *pCx){
  if( pCx==0 ){
    return;
  }
  if( pCx->pCursor ){
    sqlite3BtreeCloseCursor(pCx->pCursor);
  }


  if( pCx->pBt ){
    sqlite3BtreeClose(pCx->pBt);
  }
#ifndef SQLITE_OMIT_VIRTUALTABLE
  if( pCx->pVtabCursor ){
    sqlite3_vtab_cursor *pVtabCursor = pCx->pVtabCursor;
    const sqlite3_module *pModule = pCx->pModule;
    p->inVtabMethod = 1;
    (void)sqlite3SafetyOff(p->db);

** This module contains C code that generates VDBE code used to process
** the WHERE clause of SQL statements.  This module is responsible for
** generating the code that loops through a table looking for applicable
** rows.  Indices are selected and used to speed the search when doing
** so is applicable.  Because this module is responsible for selecting
** indices, you might also think of this module as the "query optimizer".
**
** $Id: where.c,v 1.315 2008/07/09 13:28:54 drh Exp $
*/
#include "sqliteInt.h"

/*
** The number of bits in a Bitmask.  "BMS" means "BitMask Size".
*/
#define BMS  (sizeof(Bitmask)*8)

        assert(pX->pLeft);
        pColl = sqlite3BinaryCompareCollSeq(pParse, pX->pLeft, pX->pRight);
        if( !pColl ){
          pColl = pParse->db->pDfltColl;
        }

        for(j=0; pIdx->aiColumn[j]!=iColumn; j++){
          failsafe( j>=pIdx->nColumn, 0x0128fc98, {return 0;});
        }
        if( sqlite3StrICmp(pColl->zName, pIdx->azColl[j]) ) continue;
      }
      return pTerm;
    }
  }
  return 0;

      if( pTerm==0 ) break;
      flags |= WHERE_COLUMN_EQ;
      if( pTerm->eOperator & WO_IN ){
        Expr *pExpr = pTerm->pExpr;
        flags |= WHERE_COLUMN_IN;
        if( pExpr->pSelect!=0 ){
          inMultiplier *= 25;
        }else{
          failsafe( pExpr->pList==0, 0x16b91d0f, continue);
          inMultiplier *= pExpr->pList->nExpr + 1;
        }
      }
    }
    cost = pProbe->aiRowEst[i] * inMultiplier * estLog(inMultiplier);
    nEq = i;
    if( pProbe->onError!=OE_None && (flags & WHERE_COLUMN_IN)==0

** loop.  We would get the correct results if nothing were ever disabled,
** but joins might run a little slower.  The trick is to disable as much
** as we can without disabling too much.  If we disabled in (1), we'd get
** the wrong answer.  See ticket #813.
*/
static void disableTerm(WhereLevel *pLevel, WhereTerm *pTerm){
  if( pTerm

      && (pLevel->iLeftJoin==0 || ExprHasProperty(pTerm->pExpr, EP_FromJoin))
  ){
    failsafe( (pTerm->flags & TERM_CODED)!=0, 0x641154a4, /* no-op */ );
    pTerm->flags |= TERM_CODED;
    if( pTerm->iParent>=0 ){
      WhereTerm *pOther = &pTerm->pWC->a[pTerm->iParent];
      if( (--pOther->nChild)==0 ){
        disableTerm(pLevel, pOther);
      }
    }

  /* Evaluate the equality constraints
  */
  assert( pIdx->nColumn>=nEq );
  for(j=0; j<nEq; j++){
    int r1;
    int k = pIdx->aiColumn[j];
    pTerm = findTerm(pWC, iCur, k, notReady, pLevel->flags, pIdx);
    failsafe( pTerm==0, 0x7592494c, break );
    assert( (pTerm->flags & TERM_CODED)==0 );
    r1 = codeEqualityTerm(pParse, pTerm, pLevel, regBase+j);
    if( r1!=regBase+j ){
      sqlite3VdbeAddOp2(v, OP_SCopy, r1, regBase+j);
    }
    testcase( pTerm->eOperator & WO_ISNULL );
    testcase( pTerm->eOperator & WO_IN );

# 2001 September 15
#
# 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 some common TCL routines used for regression
# testing the SQLite library
#
# $Id: tester.tcl,v 1.130 2008/07/09 16:51:52 drh Exp $

#
# What for user input before continuing.  This gives an opportunity
# to connect profiling tools to the process.
#
for {set i 0} {$i<[llength $argv]} {incr i} {
  if {[regexp {^-+pause$} [lindex $argv $i] all value]} {

  }
  sqlite3_soft_heap_limit 0
  incr nTest
  puts "$nErr errors out of $nTest tests"
  if {$nErr>0} {
    puts "Failures on these tests: $::failList"
  }
  set failsafe [lindex [sqlite3_status SQLITE_STATUS_FAILSAFE 1] 1]
  if {$failsafe} {
    puts "Failsafe error code [format 0x%08x $failsafe]"
    incr nErr
  }
  set fs2 [lindex [sqlite3_status SQLITE_STATUS_FAILSAFE 0] 1]
  if {$fs2} {
    puts "Failsafe failed to reset"
    incr nErr
  }
  if {[llength $omitList]>0} {
    puts "Omitted test cases:"
    set prec {}
    foreach {rec} [lsort $omitList] {
      if {$rec==$prec} continue
      set prec $rec
      puts [format {  %-12s %s} [lindex $rec 0] [lindex $rec 1]]