** 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 1.410 2007/08/23 02:47:53 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"

................................................................................
  sqlite3_vfs *pVfs;      /* The VFS to use for this btree */
  BtShared *pBt = 0;      /* Shared part of btree structure */
  Btree *p;               /* Handle to return */
  int rc = SQLITE_OK;
  int nReserve;
  unsigned char zDbHeader[100];

  if( pSqlite ){
    pVfs = pSqlite->pVfs;
  }else{
    pVfs = sqlite3_vfs_find(0);
  }
  assert( sqlite3BtreeMutexHeld(pSqlite->mutex) );

  /* Set the variable isMemdb to true for an in-memory database, or 
  ** false for a file-based database. This symbol is only required if
  ** either of the shared-data or autovacuum features are compiled 
  ** into the library.
  */
#if !defined(SQLITE_OMIT_SHARED_CACHE) || !defined(SQLITE_OMIT_AUTOVACUUM)
  #ifdef SQLITE_OMIT_MEMORYDB
    const int isMemdb = 0;
  #else
    const int isMemdb = zFilename && !strcmp(zFilename, ":memory:");
  #endif
#endif








  p = sqlite3MallocZero(sizeof(Btree));
  if( !p ){
    return SQLITE_NOMEM;
  }
  p->inTrans = TRANS_NONE;
  p->pSqlite = pSqlite;

** 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 1.411 2007/08/24 03:51:33 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"

................................................................................
  sqlite3_vfs *pVfs;      /* The VFS to use for this btree */
  BtShared *pBt = 0;      /* Shared part of btree structure */
  Btree *p;               /* Handle to return */
  int rc = SQLITE_OK;
  int nReserve;
  unsigned char zDbHeader[100];








  /* Set the variable isMemdb to true for an in-memory database, or 
  ** false for a file-based database. This symbol is only required if
  ** either of the shared-data or autovacuum features are compiled 
  ** into the library.
  */
#if !defined(SQLITE_OMIT_SHARED_CACHE) || !defined(SQLITE_OMIT_AUTOVACUUM)
  #ifdef SQLITE_OMIT_MEMORYDB
    const int isMemdb = 0;
  #else
    const int isMemdb = zFilename && !strcmp(zFilename, ":memory:");
  #endif
#endif

  if( pSqlite ){
    pVfs = pSqlite->pVfs;
  }else{
    pVfs = sqlite3_vfs_find(0);
  }
  assert( sqlite3BtreeMutexHeld(pSqlite->mutex) );

  p = sqlite3MallocZero(sizeof(Btree));
  if( !p ){
    return SQLITE_NOMEM;
  }
  p->inTrans = TRANS_NONE;
  p->pSqlite = pSqlite;

** This file contains the C functions that implement date and time
** functions for SQLite.  
**
** There is only one exported symbol in this file - the function
** sqlite3RegisterDateTimeFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: date.c,v 1.71 2007/08/21 19:33:56 drh Exp $
**
** SQLite processes all times and dates as Julian Day numbers.  The
** dates and times are stored as the number of days since noon
** in Greenwich on November 24, 4714 B.C. according to the Gregorian
** calendar system. 
**
** 1970-01-01 00:00:00 is JD 2440587.5
................................................................................
    y.h = sLocal.tm_hour;
    y.m = sLocal.tm_min;
    y.s = sLocal.tm_sec;
  }
#else
  {
    struct tm *pTm;
    sqlite3_mutex_enter(sqlite3_mutex_alloc(SQLITE_MUTEX_GLOBAL));
    pTm = localtime(&t);
    y.Y = pTm->tm_year + 1900;
    y.M = pTm->tm_mon + 1;
    y.D = pTm->tm_mday;
    y.h = pTm->tm_hour;
    y.m = pTm->tm_min;
    y.s = pTm->tm_sec;
    sqlite3_mutex_leave(sqlite3_mutex_alloc(SQLITE_MUTEX_GLOBAL));
  }
#endif
  y.validYMD = 1;
  y.validHMS = 1;
  y.validJD = 0;
  y.validTZ = 0;
  computeJD(&y);

** This file contains the C functions that implement date and time
** functions for SQLite.  
**
** There is only one exported symbol in this file - the function
** sqlite3RegisterDateTimeFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: date.c,v 1.72 2007/08/24 03:51:33 drh Exp $
**
** SQLite processes all times and dates as Julian Day numbers.  The
** dates and times are stored as the number of days since noon
** in Greenwich on November 24, 4714 B.C. according to the Gregorian
** calendar system. 
**
** 1970-01-01 00:00:00 is JD 2440587.5
................................................................................
    y.h = sLocal.tm_hour;
    y.m = sLocal.tm_min;
    y.s = sLocal.tm_sec;
  }
#else
  {
    struct tm *pTm;
    sqlite3_mutex_enter(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER));
    pTm = localtime(&t);
    y.Y = pTm->tm_year + 1900;
    y.M = pTm->tm_mon + 1;
    y.D = pTm->tm_mday;
    y.h = pTm->tm_hour;
    y.m = pTm->tm_min;
    y.s = pTm->tm_sec;
    sqlite3_mutex_leave(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER));
  }
#endif
  y.validYMD = 1;
  y.validHMS = 1;
  y.validJD = 0;
  y.validTZ = 0;
  computeJD(&y);

**
*************************************************************************
** 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 1.396 2007/08/22 20:18:22 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** The version of the library
*/
................................................................................
  CollSeq *pColl;

  /* Allocate the sqlite data structure */
  db = sqlite3MallocZero( sizeof(sqlite3) );
  if( db==0 ) goto opendb_out;
  db->mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_RECURSIVE);
  if( db->mutex==0 ){
    db->mallocFailed = 1;

    goto opendb_out;
  }
  sqlite3_mutex_enter(db->mutex);
  db->pVfs = sqlite3_vfs_find(zVfs);
  db->errMask = 0xff;
  db->priorNewRowid = 0;
  db->magic = SQLITE_MAGIC_BUSY;
  db->nDb = 2;

  db->aDb = db->aDbStatic;
  db->autoCommit = 1;
  db->flags |= SQLITE_ShortColNames
#if SQLITE_DEFAULT_FILE_FORMAT<4
                 | SQLITE_LegacyFileFmt
#endif
#ifdef SQLITE_ENABLE_LOAD_EXTENSION
................................................................................
#ifdef SQLITE_DEFAULT_LOCKING_MODE
  db->dfltLockMode = SQLITE_DEFAULT_LOCKING_MODE;
  sqlite3PagerLockingMode(sqlite3BtreePager(db->aDb[0].pBt),
                          SQLITE_DEFAULT_LOCKING_MODE);
#endif

opendb_out:
  if( db ){
    sqlite3_mutex_leave(db->mutex);
  }
  if( SQLITE_NOMEM==(rc = sqlite3_errcode(db)) ){
    sqlite3_close(db);
    db = 0;
  }
  *ppDb = db;

**
*************************************************************************
** 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 1.397 2007/08/24 03:51:34 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>

/*
** The version of the library
*/
................................................................................
  CollSeq *pColl;

  /* Allocate the sqlite data structure */
  db = sqlite3MallocZero( sizeof(sqlite3) );
  if( db==0 ) goto opendb_out;
  db->mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_RECURSIVE);
  if( db->mutex==0 ){
    sqlite3_free(db);
    db = 0;
    goto opendb_out;
  }
  sqlite3_mutex_enter(db->mutex);
  db->pVfs = sqlite3_vfs_find(zVfs);
  db->errMask = 0xff;
  db->priorNewRowid = 0;

  db->nDb = 2;
  db->magic = SQLITE_MAGIC_BUSY;
  db->aDb = db->aDbStatic;
  db->autoCommit = 1;
  db->flags |= SQLITE_ShortColNames
#if SQLITE_DEFAULT_FILE_FORMAT<4
                 | SQLITE_LegacyFileFmt
#endif
#ifdef SQLITE_ENABLE_LOAD_EXTENSION
................................................................................
#ifdef SQLITE_DEFAULT_LOCKING_MODE
  db->dfltLockMode = SQLITE_DEFAULT_LOCKING_MODE;
  sqlite3PagerLockingMode(sqlite3BtreePager(db->aDb[0].pBt),
                          SQLITE_DEFAULT_LOCKING_MODE);
#endif

opendb_out:
  if( db && db->mutex ){
    sqlite3_mutex_leave(db->mutex);
  }
  if( SQLITE_NOMEM==(rc = sqlite3_errcode(db)) ){
    sqlite3_close(db);
    db = 0;
  }
  *ppDb = db;

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Memory allocation functions used throughout sqlite.
**
**
** $Id: malloc.c,v 1.10 2007/08/22 20:18:22 drh Exp $
*/
#include "sqliteInt.h"
#include <stdarg.h>
#include <ctype.h>

/*
** This routine runs when the memory allocator sees that the
** total memory allocation is about to exceed the soft heap
** limit.
*/
static void softHeapLimitEnforcer(
  void *NotUsed, 
  sqlite3_uint64 inUse,
  unsigned int allocSize
){
  sqlite3_release_memory(allocSize);
}

/*
** Set the soft heap-size limit for the current thread. Passing a
** zero or negative value indicates no limit.

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** Memory allocation functions used throughout sqlite.
**
**
** $Id: malloc.c,v 1.11 2007/08/24 03:51:34 drh Exp $
*/
#include "sqliteInt.h"
#include <stdarg.h>
#include <ctype.h>

/*
** This routine runs when the memory allocator sees that the
** total memory allocation is about to exceed the soft heap
** limit.
*/
static void softHeapLimitEnforcer(
  void *NotUsed, 
  sqlite3_int64 inUse,
  int allocSize
){
  sqlite3_release_memory(allocSize);
}

/*
** Set the soft heap-size limit for the current thread. Passing a
** zero or negative value indicates no limit.

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains the C functions that implement a memory
** allocation subsystem for use by SQLite.  
**
** $Id: mem1.c,v 1.7 2007/08/22 20:18:22 drh Exp $
*/

/*
** This version of the memory allocator is the default.  It is
** used when no other memory allocator is specified using compile-time
** macros.
*/
................................................................................
  /*
  ** The alarm callback and its arguments.  The mem.mutex lock will
  ** be held while the callback is running.  Recursive calls into
  ** the memory subsystem are allowed, but no new callbacks will be
  ** issued.  The alarmBusy variable is set to prevent recursive
  ** callbacks.
  */
  sqlite3_uint64 alarmThreshold;
  void (*alarmCallback)(void*, sqlite3_uint64, unsigned);
  void *alarmArg;
  int alarmBusy;
  
  /*
  ** Mutex to control access to the memory allocation subsystem.
  */
  sqlite3_mutex *mutex;
  
  /*
  ** Current allocation and high-water mark.
  */
  sqlite3_uint64 nowUsed;
  sqlite3_uint64 mxUsed;
  
 
} mem = {  /* This variable holds all of the local data */
   ((sqlite3_uint64)1)<<63,    /* alarmThreshold */
   /* Everything else is initialized to zero */
};



/*
** Return the amount of memory currently checked out.
*/
sqlite3_uint64 sqlite3_memory_used(void){
  sqlite3_uint64 n;
  if( mem.mutex==0 ){
    mem.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM);
  }
  sqlite3_mutex_enter(mem.mutex);
  n = mem.nowUsed;
  sqlite3_mutex_leave(mem.mutex);  
  return n;
................................................................................
}

/*
** Return the maximum amount of memory that has ever been
** checked out since either the beginning of this process
** or since the most recent reset.
*/
sqlite3_uint64 sqlite3_memory_highwater(int resetFlag){
  sqlite3_uint64 n;
  if( mem.mutex==0 ){
    mem.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM);
  }
  sqlite3_mutex_enter(mem.mutex);
  n = mem.mxUsed;
  if( resetFlag ){
    mem.mxUsed = mem.nowUsed;
................................................................................
  return n;
}

/*
** Change the alarm callback
*/
int sqlite3_memory_alarm(
  void(*xCallback)(void *pArg, sqlite3_uint64 used, unsigned int N),
  void *pArg,
  sqlite3_uint64 iThreshold
){
  if( mem.mutex==0 ){
    mem.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM);
  }
  sqlite3_mutex_enter(mem.mutex);
  mem.alarmCallback = xCallback;
  mem.alarmArg = pArg;
................................................................................
  sqlite3_mutex_leave(mem.mutex);
  return SQLITE_OK;
}

/*
** Trigger the alarm 
*/
static void sqlite3MemsysAlarm(unsigned nByte){
  void (*xCallback)(void*,sqlite3_uint64,unsigned);
  sqlite3_uint64 nowUsed;
  void *pArg;
  if( mem.alarmCallback==0 || mem.alarmBusy  ) return;
  mem.alarmBusy = 1;
  xCallback = mem.alarmCallback;
  nowUsed = mem.nowUsed;
  pArg = mem.alarmArg;
  sqlite3_mutex_leave(mem.mutex);
................................................................................
  mem.alarmBusy = 0;
}

/*
** Allocate nBytes of memory
*/
void *sqlite3_malloc(int nBytes){
  sqlite3_uint64 *p;
  if( nBytes<=0 ){
    return 0;
  }
  if( mem.mutex==0 ){
    mem.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM);
  }
  sqlite3_mutex_enter(mem.mutex);
  if( mem.nowUsed+nBytes>=mem.alarmThreshold ){
    sqlite3MemsysAlarm(nBytes);
  }
  p = malloc(nBytes+8);
  if( p==0 ){
    sqlite3MemsysAlarm(nBytes);
    p = malloc(nBytes+8);
  }
................................................................................
  return (void*)p; 
}

/*
** Free memory.
*/
void sqlite3_free(void *pPrior){
  sqlite3_uint64 *p;
  unsigned nByte;
  if( pPrior==0 ){
    return;
  }
  assert( mem.mutex!=0 );
  p = pPrior;
  p--;
  nByte = (unsigned int)*p;
  sqlite3_mutex_enter(mem.mutex);
  mem.nowUsed -= nByte;
  free(p);
  sqlite3_mutex_leave(mem.mutex);  
}

/*
** Change the size of an existing memory allocation
*/
void *sqlite3_realloc(void *pPrior, int nBytes){
  unsigned nOld;
  sqlite3_uint64 *p;
  if( pPrior==0 ){
    return sqlite3_malloc(nBytes);
  }
  if( nBytes<=0 ){
    sqlite3_free(pPrior);
    return 0;
  }
  p = pPrior;
  p--;
  nOld = (unsigned int)p[0];
  assert( mem.mutex!=0 );
  sqlite3_mutex_enter(mem.mutex);
  if( mem.nowUsed+nBytes-nOld>=mem.alarmThreshold ){
    sqlite3MemsysAlarm(nBytes-nOld);
  }
  p = realloc(p, nBytes+8);
  if( p==0 ){

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains the C functions that implement a memory
** allocation subsystem for use by SQLite.  
**
** $Id: mem1.c,v 1.8 2007/08/24 03:51:34 drh Exp $
*/

/*
** This version of the memory allocator is the default.  It is
** used when no other memory allocator is specified using compile-time
** macros.
*/
................................................................................
  /*
  ** The alarm callback and its arguments.  The mem.mutex lock will
  ** be held while the callback is running.  Recursive calls into
  ** the memory subsystem are allowed, but no new callbacks will be
  ** issued.  The alarmBusy variable is set to prevent recursive
  ** callbacks.
  */
  sqlite3_int64 alarmThreshold;
  void (*alarmCallback)(void*, sqlite3_int64,int);
  void *alarmArg;
  int alarmBusy;
  
  /*
  ** Mutex to control access to the memory allocation subsystem.
  */
  sqlite3_mutex *mutex;
  
  /*
  ** Current allocation and high-water mark.
  */
  sqlite3_int64 nowUsed;
  sqlite3_int64 mxUsed;
  
 
} mem;






/*
** Return the amount of memory currently checked out.
*/
sqlite3_int64 sqlite3_memory_used(void){
  sqlite3_int64 n;
  if( mem.mutex==0 ){
    mem.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM);
  }
  sqlite3_mutex_enter(mem.mutex);
  n = mem.nowUsed;
  sqlite3_mutex_leave(mem.mutex);  
  return n;
................................................................................
}

/*
** Return the maximum amount of memory that has ever been
** checked out since either the beginning of this process
** or since the most recent reset.
*/
sqlite3_int64 sqlite3_memory_highwater(int resetFlag){
  sqlite3_int64 n;
  if( mem.mutex==0 ){
    mem.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM);
  }
  sqlite3_mutex_enter(mem.mutex);
  n = mem.mxUsed;
  if( resetFlag ){
    mem.mxUsed = mem.nowUsed;
................................................................................
  return n;
}

/*
** Change the alarm callback
*/
int sqlite3_memory_alarm(
  void(*xCallback)(void *pArg, sqlite3_int64 used,int N),
  void *pArg,
  sqlite3_int64 iThreshold
){
  if( mem.mutex==0 ){
    mem.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM);
  }
  sqlite3_mutex_enter(mem.mutex);
  mem.alarmCallback = xCallback;
  mem.alarmArg = pArg;
................................................................................
  sqlite3_mutex_leave(mem.mutex);
  return SQLITE_OK;
}

/*
** Trigger the alarm 
*/
static void sqlite3MemsysAlarm(int nByte){
  void (*xCallback)(void*,sqlite3_int64,int);
  sqlite3_int64 nowUsed;
  void *pArg;
  if( mem.alarmCallback==0 || mem.alarmBusy  ) return;
  mem.alarmBusy = 1;
  xCallback = mem.alarmCallback;
  nowUsed = mem.nowUsed;
  pArg = mem.alarmArg;
  sqlite3_mutex_leave(mem.mutex);
................................................................................
  mem.alarmBusy = 0;
}

/*
** Allocate nBytes of memory
*/
void *sqlite3_malloc(int nBytes){
  sqlite3_int64 *p;
  if( nBytes<=0 ){
    return 0;
  }
  if( mem.mutex==0 ){
    mem.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM);
  }
  sqlite3_mutex_enter(mem.mutex);
  if( mem.alarmCallback!=0 && mem.nowUsed+nBytes>=mem.alarmThreshold ){
    sqlite3MemsysAlarm(nBytes);
  }
  p = malloc(nBytes+8);
  if( p==0 ){
    sqlite3MemsysAlarm(nBytes);
    p = malloc(nBytes+8);
  }
................................................................................
  return (void*)p; 
}

/*
** Free memory.
*/
void sqlite3_free(void *pPrior){
  sqlite3_int64 *p;
  int nByte;
  if( pPrior==0 ){
    return;
  }
  assert( mem.mutex!=0 );
  p = pPrior;
  p--;
  nByte = (int)*p;
  sqlite3_mutex_enter(mem.mutex);
  mem.nowUsed -= nByte;
  free(p);
  sqlite3_mutex_leave(mem.mutex);  
}

/*
** Change the size of an existing memory allocation
*/
void *sqlite3_realloc(void *pPrior, int nBytes){
  int nOld;
  sqlite3_int64 *p;
  if( pPrior==0 ){
    return sqlite3_malloc(nBytes);
  }
  if( nBytes<=0 ){
    sqlite3_free(pPrior);
    return 0;
  }
  p = pPrior;
  p--;
  nOld = (int)p[0];
  assert( mem.mutex!=0 );
  sqlite3_mutex_enter(mem.mutex);
  if( mem.nowUsed+nBytes-nOld>=mem.alarmThreshold ){
    sqlite3MemsysAlarm(nBytes-nOld);
  }
  p = realloc(p, nBytes+8);
  if( p==0 ){

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains the C functions that implement a memory
** allocation subsystem for use by SQLite.  
**
** $Id: mem2.c,v 1.8 2007/08/23 02:47:53 drh Exp $
*/

/*
** This version of the memory allocator is used only if the
** SQLITE_MEMDEBUG macro is defined and SQLITE_OMIT_MEMORY_ALLOCATION
** is not defined.
*/
................................................................................
** to back up from the allocation pointer to find the MemBlockHdr.  The
** MemBlockHdr tells us the size of the allocation and the number of
** backtrace pointers.  There is also a guard word at the end of the
** MemBlockHdr.
*/
struct MemBlockHdr {
  struct MemBlockHdr *pNext, *pPrev;  /* Linked list of all unfreed memory */
  unsigned int iSize;                 /* Size of this allocation */
  unsigned char nBacktrace;           /* Number of backtraces on this alloc */
  unsigned char nBacktraceSlots;      /* Available backtrace slots */
  unsigned short nTitle;              /* Bytes of title; includes '\0' */
  unsigned int iForeGuard;            /* Guard word for sanity */
};

/*
** Guard words
*/
#define FOREGUARD 0x80F5E153
#define REARGUARD 0xE4676B53
................................................................................
  /*
  ** The alarm callback and its arguments.  The mem.mutex lock will
  ** be held while the callback is running.  Recursive calls into
  ** the memory subsystem are allowed, but no new callbacks will be
  ** issued.  The alarmBusy variable is set to prevent recursive
  ** callbacks.
  */
  sqlite3_uint64 alarmThreshold;
  void (*alarmCallback)(void*, sqlite3_uint64, unsigned);
  void *alarmArg;
  int alarmBusy;
  
  /*
  ** Mutex to control access to the memory allocation subsystem.
  */
  sqlite3_mutex *mutex;
  
  /*
  ** Current allocation and high-water mark.
  */
  sqlite3_uint64 nowUsed;
  sqlite3_uint64 mxUsed;
  
  /*
  ** Head and tail of a linked list of all outstanding allocations
  */
  struct MemBlockHdr *pFirst;
  struct MemBlockHdr *pLast;
  
................................................................................
  /* 
  ** sqlite3MallocDisallow() increments the following counter.
  ** sqlite3MallocAllow() decrements it.
  */
  int disallow; /* Do not allow memory allocation */
  
  
} mem = {  /* This variable holds all of the local data */
   ((sqlite3_uint64)1)<<63,    /* alarmThreshold */
   /* Everything else is initialized to zero */
};



/*
** Return the amount of memory currently checked out.
*/
sqlite3_uint64 sqlite3_memory_used(void){
  sqlite3_uint64 n;
  if( mem.mutex==0 ){
    mem.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM);
  }
  sqlite3_mutex_enter(mem.mutex);
  n = mem.nowUsed;
  sqlite3_mutex_leave(mem.mutex);  
  return n;
................................................................................
}

/*
** Return the maximum amount of memory that has ever been
** checked out since either the beginning of this process
** or since the most recent reset.
*/
sqlite3_uint64 sqlite3_memory_highwater(int resetFlag){
  sqlite3_uint64 n;
  if( mem.mutex==0 ){
    mem.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM);
  }
  sqlite3_mutex_enter(mem.mutex);
  n = mem.mxUsed;
  if( resetFlag ){
    mem.mxUsed = mem.nowUsed;
................................................................................
  return n;
}

/*
** Change the alarm callback
*/
int sqlite3_memory_alarm(
  void(*xCallback)(void *pArg, sqlite3_uint64 used, unsigned int N),
  void *pArg,
  sqlite3_uint64 iThreshold
){
  if( mem.mutex==0 ){
    mem.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM);
  }
  sqlite3_mutex_enter(mem.mutex);
  mem.alarmCallback = xCallback;
  mem.alarmArg = pArg;
................................................................................
  sqlite3_mutex_leave(mem.mutex);
  return SQLITE_OK;
}

/*
** Trigger the alarm 
*/
static void sqlite3MemsysAlarm(unsigned nByte){
  void (*xCallback)(void*,sqlite3_uint64,unsigned);
  sqlite3_uint64 nowUsed;
  void *pArg;
  if( mem.alarmCallback==0 || mem.alarmBusy  ) return;
  mem.alarmBusy = 1;
  xCallback = mem.alarmCallback;
  nowUsed = mem.nowUsed;
  pArg = mem.alarmArg;
  sqlite3_mutex_leave(mem.mutex);
................................................................................
** Given an allocation, find the MemBlockHdr for that allocation.
**
** This routine checks the guards at either end of the allocation and
** if they are incorrect it asserts.
*/
static struct MemBlockHdr *sqlite3MemsysGetHeader(void *pAllocation){
  struct MemBlockHdr *p;
  unsigned int *pInt;

  p = (struct MemBlockHdr*)pAllocation;
  p--;
  assert( p->iForeGuard==FOREGUARD );
  assert( (p->iSize & 3)==0 );
  pInt = (unsigned int*)pAllocation;
  assert( pInt[p->iSize/sizeof(unsigned int)]==REARGUARD );
  return p;
}

/*
** This routine is called once the first time a simulated memory
** failure occurs.  The sole purpose of this routine is to provide
** a convenient place to set a debugger breakpoint when debugging
................................................................................
/*
** Allocate nByte bytes of memory.
*/
void *sqlite3_malloc(int nByte){
  struct MemBlockHdr *pHdr;
  void **pBt;
  char *z;
  unsigned int *pInt;
  void *p;
  unsigned int totalSize;

  if( nByte<=0 ){
    return 0;
  }
  if( mem.mutex==0 ){
    mem.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM);
  }
  sqlite3_mutex_enter(mem.mutex);
  assert( mem.disallow==0 );
  if( mem.nowUsed+nByte>=mem.alarmThreshold ){
    sqlite3MemsysAlarm(nByte);
  }
  nByte = (nByte+3)&~3;
  totalSize = nByte + sizeof(*pHdr) + sizeof(unsigned int) +
               mem.nBacktrace*sizeof(void*) + mem.nTitle;
  if( mem.iFail>0 ){
    if( mem.iFail==1 ){
      p = 0;
      mem.iFail = mem.iReset;
      if( mem.iFailCnt==0 ){
        sqlite3MemsysFailed();  /* A place to set a breakpoint */
................................................................................
    }else{
      pHdr->nBacktrace = 0;
    }
    if( mem.nTitle ){
      memcpy(z, mem.zTitle, mem.nTitle);
    }
    pHdr->iSize = nByte;
    pInt = (unsigned int *)&pHdr[1];
    pInt[nByte/sizeof(unsigned int)] = REARGUARD;
    memset(pInt, 0x65, nByte);
    mem.nowUsed += nByte;
    if( mem.nowUsed>mem.mxUsed ){
      mem.mxUsed = mem.nowUsed;
    }
    p = (void*)pInt;
  }
................................................................................
  }else{
    assert( mem.pLast==pHdr );
    mem.pLast = pHdr->pPrev;
  }
  z = (char*)pBt;
  z -= pHdr->nTitle;
  memset(z, 0x2b, sizeof(void*)*pHdr->nBacktraceSlots + sizeof(*pHdr) +
                  pHdr->iSize + sizeof(unsigned int) + pHdr->nTitle);
  free(z);
  sqlite3_mutex_leave(mem.mutex);  
}

/*
** Change the size of an existing memory allocation.
**
................................................................................
  if( iRepeat>=0 ){
    mem.iReset = iRepeat;
  }
  mem.iFailCnt = 0;
  return n;
}

/*
** This routine returns the number of successful mallocs remaining until
** the next simulated malloc failure.  -1 is returned if no simulated
** failure is currently scheduled.
*/
int sqlite3_memdebug_pending(void){
  return mem.iFail-1;
}

/*
** The following two routines are used to assert that no memory
** allocations occur between one call and the next.  The use of
** these routines does not change the computed results in any way.
** These routines are like asserts.
*/
void sqlite3MallocDisallow(void){

**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains the C functions that implement a memory
** allocation subsystem for use by SQLite.  
**
** $Id: mem2.c,v 1.9 2007/08/24 03:51:34 drh Exp $
*/

/*
** This version of the memory allocator is used only if the
** SQLITE_MEMDEBUG macro is defined and SQLITE_OMIT_MEMORY_ALLOCATION
** is not defined.
*/
................................................................................
** to back up from the allocation pointer to find the MemBlockHdr.  The
** MemBlockHdr tells us the size of the allocation and the number of
** backtrace pointers.  There is also a guard word at the end of the
** MemBlockHdr.
*/
struct MemBlockHdr {
  struct MemBlockHdr *pNext, *pPrev;  /* Linked list of all unfreed memory */
  int iSize;                          /* Size of this allocation */
  char nBacktrace;                    /* Number of backtraces on this alloc */
  char nBacktraceSlots;               /* Available backtrace slots */
  short nTitle;                       /* Bytes of title; includes '\0' */
  int iForeGuard;                     /* Guard word for sanity */
};

/*
** Guard words
*/
#define FOREGUARD 0x80F5E153
#define REARGUARD 0xE4676B53
................................................................................
  /*
  ** The alarm callback and its arguments.  The mem.mutex lock will
  ** be held while the callback is running.  Recursive calls into
  ** the memory subsystem are allowed, but no new callbacks will be
  ** issued.  The alarmBusy variable is set to prevent recursive
  ** callbacks.
  */
  sqlite3_int64 alarmThreshold;
  void (*alarmCallback)(void*, sqlite3_int64, int);
  void *alarmArg;
  int alarmBusy;
  
  /*
  ** Mutex to control access to the memory allocation subsystem.
  */
  sqlite3_mutex *mutex;
  
  /*
  ** Current allocation and high-water mark.
  */
  sqlite3_int64 nowUsed;
  sqlite3_int64 mxUsed;
  
  /*
  ** Head and tail of a linked list of all outstanding allocations
  */
  struct MemBlockHdr *pFirst;
  struct MemBlockHdr *pLast;
  
................................................................................
  /* 
  ** sqlite3MallocDisallow() increments the following counter.
  ** sqlite3MallocAllow() decrements it.
  */
  int disallow; /* Do not allow memory allocation */
  
  
} mem;






/*
** Return the amount of memory currently checked out.
*/
sqlite3_int64 sqlite3_memory_used(void){
  sqlite3_int64 n;
  if( mem.mutex==0 ){
    mem.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM);
  }
  sqlite3_mutex_enter(mem.mutex);
  n = mem.nowUsed;
  sqlite3_mutex_leave(mem.mutex);  
  return n;
................................................................................
}

/*
** Return the maximum amount of memory that has ever been
** checked out since either the beginning of this process
** or since the most recent reset.
*/
sqlite3_int64 sqlite3_memory_highwater(int resetFlag){
  sqlite3_int64 n;
  if( mem.mutex==0 ){
    mem.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM);
  }
  sqlite3_mutex_enter(mem.mutex);
  n = mem.mxUsed;
  if( resetFlag ){
    mem.mxUsed = mem.nowUsed;
................................................................................
  return n;
}

/*
** Change the alarm callback
*/
int sqlite3_memory_alarm(
  void(*xCallback)(void *pArg, sqlite3_int64 used, int N),
  void *pArg,
  sqlite3_int64 iThreshold
){
  if( mem.mutex==0 ){
    mem.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM);
  }
  sqlite3_mutex_enter(mem.mutex);
  mem.alarmCallback = xCallback;
  mem.alarmArg = pArg;
................................................................................
  sqlite3_mutex_leave(mem.mutex);
  return SQLITE_OK;
}

/*
** Trigger the alarm 
*/
static void sqlite3MemsysAlarm(int nByte){
  void (*xCallback)(void*,sqlite3_int64,int);
  sqlite3_int64 nowUsed;
  void *pArg;
  if( mem.alarmCallback==0 || mem.alarmBusy  ) return;
  mem.alarmBusy = 1;
  xCallback = mem.alarmCallback;
  nowUsed = mem.nowUsed;
  pArg = mem.alarmArg;
  sqlite3_mutex_leave(mem.mutex);
................................................................................
** Given an allocation, find the MemBlockHdr for that allocation.
**
** This routine checks the guards at either end of the allocation and
** if they are incorrect it asserts.
*/
static struct MemBlockHdr *sqlite3MemsysGetHeader(void *pAllocation){
  struct MemBlockHdr *p;
  int *pInt;

  p = (struct MemBlockHdr*)pAllocation;
  p--;
  assert( p->iForeGuard==FOREGUARD );
  assert( (p->iSize & 3)==0 );
  pInt = (int*)pAllocation;
  assert( pInt[p->iSize/sizeof(int)]==REARGUARD );
  return p;
}

/*
** This routine is called once the first time a simulated memory
** failure occurs.  The sole purpose of this routine is to provide
** a convenient place to set a debugger breakpoint when debugging
................................................................................
/*
** Allocate nByte bytes of memory.
*/
void *sqlite3_malloc(int nByte){
  struct MemBlockHdr *pHdr;
  void **pBt;
  char *z;
  int *pInt;
  void *p;
  int totalSize;

  if( nByte<=0 ){
    return 0;
  }
  if( mem.mutex==0 ){
    mem.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MEM);
  }
  sqlite3_mutex_enter(mem.mutex);
  assert( mem.disallow==0 );
  if( mem.alarmCallback!=0 && mem.nowUsed+nByte>=mem.alarmThreshold ){
    sqlite3MemsysAlarm(nByte);
  }
  nByte = (nByte+3)&~3;
  totalSize = nByte + sizeof(*pHdr) + sizeof(int) +
               mem.nBacktrace*sizeof(void*) + mem.nTitle;
  if( mem.iFail>0 ){
    if( mem.iFail==1 ){
      p = 0;
      mem.iFail = mem.iReset;
      if( mem.iFailCnt==0 ){
        sqlite3MemsysFailed();  /* A place to set a breakpoint */
................................................................................
    }else{
      pHdr->nBacktrace = 0;
    }
    if( mem.nTitle ){
      memcpy(z, mem.zTitle, mem.nTitle);
    }
    pHdr->iSize = nByte;
    pInt = (int*)&pHdr[1];
    pInt[nByte/sizeof(int)] = REARGUARD;
    memset(pInt, 0x65, nByte);
    mem.nowUsed += nByte;
    if( mem.nowUsed>mem.mxUsed ){
      mem.mxUsed = mem.nowUsed;
    }
    p = (void*)pInt;
  }
................................................................................
  }else{
    assert( mem.pLast==pHdr );
    mem.pLast = pHdr->pPrev;
  }
  z = (char*)pBt;
  z -= pHdr->nTitle;
  memset(z, 0x2b, sizeof(void*)*pHdr->nBacktraceSlots + sizeof(*pHdr) +
                  pHdr->iSize + sizeof(int) + pHdr->nTitle);
  free(z);
  sqlite3_mutex_leave(mem.mutex);  
}

/*
** Change the size of an existing memory allocation.
**
................................................................................
  if( iRepeat>=0 ){
    mem.iReset = iRepeat;
  }
  mem.iFailCnt = 0;
  return n;
}










/*
** The following two routines are used to assert that no memory
** allocations occur between one call and the next.  The use of
** these routines does not change the computed results in any way.
** These routines are like asserts.
*/
void sqlite3MallocDisallow(void){

int sqlite3OsOpen(
  sqlite3_vfs *pVfs, 
  const char *zPath, 
  sqlite3_file *pFile, 
  int flags, 
  int *pFlagsOut
){
  return pVfs->xOpen(pVfs->pAppData, zPath, pFile, flags, pFlagsOut);
}
int sqlite3OsDelete(sqlite3_vfs *pVfs, const char *zPath, int dirSync){
  return pVfs->xDelete(pVfs->pAppData, zPath, dirSync);
}
int sqlite3OsAccess(sqlite3_vfs *pVfs, const char *zPath, int flags){
  return pVfs->xAccess(pVfs->pAppData, zPath, flags);
}
int sqlite3OsGetTempName(sqlite3_vfs *pVfs, char *zBufOut){
  return pVfs->xGetTempName(pVfs->pAppData, zBufOut);
}
int sqlite3OsFullPathname(sqlite3_vfs *pVfs, const char *zPath, char *zPathOut){
  return pVfs->xFullPathname(pVfs->pAppData, zPath, zPathOut);
}
void *sqlite3OsDlOpen(sqlite3_vfs *pVfs, const char *zPath){
  return pVfs->xDlOpen(pVfs->pAppData, zPath);
}
void sqlite3OsDlError(sqlite3_vfs *pVfs, int nByte, char *zBufOut){
  pVfs->xDlError(pVfs->pAppData, nByte, zBufOut);
}
void *sqlite3OsDlSym(sqlite3_vfs *pVfs, void *pHandle, const char *zSymbol){
  return pVfs->xDlSym(pHandle, zSymbol);
}
void sqlite3OsDlClose(sqlite3_vfs *pVfs, void *pHandle){
  pVfs->xDlClose(pHandle);
}
int sqlite3OsRandomness(sqlite3_vfs *pVfs, int nByte, char *zBufOut){
  return pVfs->xRandomness(pVfs->pAppData, nByte, zBufOut);
}
int sqlite3OsSleep(sqlite3_vfs *pVfs, int nMicro){
  return pVfs->xSleep(pVfs->pAppData, nMicro);
}
int sqlite3OsCurrentTime(sqlite3_vfs *pVfs, double *pTimeOut){
  return pVfs->xCurrentTime(pVfs->pAppData, pTimeOut);
}

int sqlite3OsOpenMalloc(
  sqlite3_vfs *pVfs, 
  const char *zFile, 
  sqlite3_file **ppFile, 
  int flags,
................................................................................
  if( pFile ){
    rc = sqlite3OsClose(pFile);
    sqlite3_free(pFile);
  }
  return rc;
}

/* 
** Default vfs implementation. Defined by the various os_X.c implementations.
*/
extern sqlite3_vfs sqlite3DefaultVfs;

/*
** The list of all registered VFS implementations.


*/
static sqlite3_vfs *vfsList = &sqlite3DefaultVfs;

/*
** Locate a VFS by name.  If no name is given, simply return the
** first VFS on the list.
*/
sqlite3_vfs *sqlite3_vfs_find(const char *zVfs){
  sqlite3_mutex *mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);
  sqlite3_vfs *pVfs;

  sqlite3_mutex_enter(mutex);




  for(pVfs = vfsList; pVfs; pVfs=pVfs->pNext){
    if( zVfs==0 ) break;
    if( strcmp(zVfs, pVfs->zName)==0 ) break;
  }
  if( pVfs ){
    pVfs->nRef++;
    assert( pVfs->nRef==1 || pVfs->vfsMutex!=0 );
................................................................................
** Release a VFS once it is no longer needed.
*/
int sqlite3_vfs_release(sqlite3_vfs *pVfs){
  sqlite3_mutex *mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);
  sqlite3_mutex_enter(mutex);
  assert( pVfs->nRef>0 );
  pVfs->nRef--;
  if( pVfs->nRef==0 ){
    sqlite3_mutex_free(pVfs->vfsMutex);
    pVfs->vfsMutex = 0;
  }
  sqlite3_mutex_leave(mutex);
  return SQLITE_OK;
}

int sqlite3OsOpen(
  sqlite3_vfs *pVfs, 
  const char *zPath, 
  sqlite3_file *pFile, 
  int flags, 
  int *pFlagsOut
){
  return pVfs->xOpen(pVfs, zPath, pFile, flags, pFlagsOut);
}
int sqlite3OsDelete(sqlite3_vfs *pVfs, const char *zPath, int dirSync){
  return pVfs->xDelete(pVfs, zPath, dirSync);
}
int sqlite3OsAccess(sqlite3_vfs *pVfs, const char *zPath, int flags){
  return pVfs->xAccess(pVfs, zPath, flags);
}
int sqlite3OsGetTempName(sqlite3_vfs *pVfs, char *zBufOut){
  return pVfs->xGetTempName(pVfs, zBufOut);
}
int sqlite3OsFullPathname(sqlite3_vfs *pVfs, const char *zPath, char *zPathOut){
  return pVfs->xFullPathname(pVfs, zPath, zPathOut);
}
void *sqlite3OsDlOpen(sqlite3_vfs *pVfs, const char *zPath){
  return pVfs->xDlOpen(pVfs, zPath);
}
void sqlite3OsDlError(sqlite3_vfs *pVfs, int nByte, char *zBufOut){
  pVfs->xDlError(pVfs, nByte, zBufOut);
}
void *sqlite3OsDlSym(sqlite3_vfs *pVfs, void *pHandle, const char *zSymbol){
  return pVfs->xDlSym(pVfs, pHandle, zSymbol);
}
void sqlite3OsDlClose(sqlite3_vfs *pVfs, void *pHandle){
  pVfs->xDlClose(pVfs, pHandle);
}
int sqlite3OsRandomness(sqlite3_vfs *pVfs, int nByte, char *zBufOut){
  return pVfs->xRandomness(pVfs, nByte, zBufOut);
}
int sqlite3OsSleep(sqlite3_vfs *pVfs, int nMicro){
  return pVfs->xSleep(pVfs, nMicro);
}
int sqlite3OsCurrentTime(sqlite3_vfs *pVfs, double *pTimeOut){
  return pVfs->xCurrentTime(pVfs, pTimeOut);
}

int sqlite3OsOpenMalloc(
  sqlite3_vfs *pVfs, 
  const char *zFile, 
  sqlite3_file **ppFile, 
  int flags,
................................................................................
  if( pFile ){
    rc = sqlite3OsClose(pFile);
    sqlite3_free(pFile);
  }
  return rc;
}

/*





** The list of all registered VFS implementations.  This list is
** initialized to the single VFS returned by sqlite3OsDefaultVfs()
** upon the first call to sqlite3_vfs_find().
*/
static sqlite3_vfs *vfsList = 0;

/*
** Locate a VFS by name.  If no name is given, simply return the
** first VFS on the list.
*/
sqlite3_vfs *sqlite3_vfs_find(const char *zVfs){
  sqlite3_mutex *mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);
  sqlite3_vfs *pVfs;
  static int isInit = 0;
  sqlite3_mutex_enter(mutex);
  if( !isInit ){
    vfsList = sqlite3OsDefaultVfs();
    isInit = 1;
  }
  for(pVfs = vfsList; pVfs; pVfs=pVfs->pNext){
    if( zVfs==0 ) break;
    if( strcmp(zVfs, pVfs->zName)==0 ) break;
  }
  if( pVfs ){
    pVfs->nRef++;
    assert( pVfs->nRef==1 || pVfs->vfsMutex!=0 );
................................................................................
** Release a VFS once it is no longer needed.
*/
int sqlite3_vfs_release(sqlite3_vfs *pVfs){
  sqlite3_mutex *mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);
  sqlite3_mutex_enter(mutex);
  assert( pVfs->nRef>0 );
  pVfs->nRef--;
  if( pVfs->nRef==0 && pVfs->vfsMutex ){
    sqlite3_mutex_free(pVfs->vfsMutex);
    pVfs->vfsMutex = 0;
  }
  sqlite3_mutex_leave(mutex);
  return SQLITE_OK;
}

/*
** Temporary files are named starting with this prefix followed by 16 random
** alphanumeric characters, and no file extension. They are stored in the
** OS's standard temporary file directory, and are deleted prior to exit.
** If sqlite is being embedded in another program, you may wish to change the
** prefix to reflect your program's name, so that if your program exits
** prematurely, old temporary files can be easily identified. This can be done
** using -DTEMP_FILE_PREFIX=myprefix_ on the compiler command line.
**
** 2006-10-31:  The default prefix used to be "sqlite_".  But then
** Mcafee started using SQLite in their anti-virus product and it
** started putting files with the "sqlite" name in the c:/temp folder.
** This annoyed many windows users.  Those users would then do a 
** Google search for "sqlite", find the telephone numbers of the
** developers and call to wake them up at night and complain.
** For this reason, the default name prefix is changed to be "sqlite" 
** spelled backwards.  So the temp files are still identified, but
** anybody smart enough to figure out the code is also likely smart
** enough to know that calling the developer will not help get rid
** of the file.
*/
#ifndef TEMP_FILE_PREFIX
# define TEMP_FILE_PREFIX "etilqs_"
#endif

/*
** If using an alternative OS interface, then we must have an "os_other.h"
** header file available for that interface.  Presumably the "os_other.h"
** header file contains #defines similar to those above.
*/
................................................................................
int sqlite3OsCloseFree(sqlite3_file *);

#if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
  int sqlite3OsFileHandle(sqlite3_file *id);
  int sqlite3OsLockState(sqlite3_file *id);
#endif















#endif /* _SQLITE_OS_H_ */

/*
** Temporary files are named starting with this prefix followed by 16 random
** alphanumeric characters, and no file extension. They are stored in the
** OS's standard temporary file directory, and are deleted prior to exit.
** If sqlite is being embedded in another program, you may wish to change the
** prefix to reflect your program's name, so that if your program exits
** prematurely, old temporary files can be easily identified. This can be done
** using -DSQLITE_TEMP_FILE_PREFIX=myprefix_ on the compiler command line.
**
** 2006-10-31:  The default prefix used to be "sqlite_".  But then
** Mcafee started using SQLite in their anti-virus product and it
** started putting files with the "sqlite" name in the c:/temp folder.
** This annoyed many windows users.  Those users would then do a 
** Google search for "sqlite", find the telephone numbers of the
** developers and call to wake them up at night and complain.
** For this reason, the default name prefix is changed to be "sqlite" 
** spelled backwards.  So the temp files are still identified, but
** anybody smart enough to figure out the code is also likely smart
** enough to know that calling the developer will not help get rid
** of the file.
*/
#ifndef SQLITE_TEMP_FILE_PREFIX
# define SQLITE_TEMP_FILE_PREFIX "etilqs_"
#endif

/*
** If using an alternative OS interface, then we must have an "os_other.h"
** header file available for that interface.  Presumably the "os_other.h"
** header file contains #defines similar to those above.
*/
................................................................................
int sqlite3OsCloseFree(sqlite3_file *);

#if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
  int sqlite3OsFileHandle(sqlite3_file *id);
  int sqlite3OsLockState(sqlite3_file *id);
#endif

/*
** Each OS-specific backend defines an instance of the following
** structure for returning a pointer to its sqlite3_vfs.  If OS_OTHER
** is defined (meaning that the application-defined OS interface layer
** is used) then there is no default VFS.   The application must
** register one or more VFS structures using sqlite3_vfs_register()
** before attempting to use SQLite.
*/
#if OS_UNIX || OS_WIN || OS_OS2
sqlite3_vfs *sqlite3OsDefaultVfs(void);
#else
# define sqlite3OsDefaultVfs(X) 0
#endif

#endif /* _SQLITE_OS_H_ */

};

/*
** Include code that is common to all os_*.c files
*/
#include "os_common.h"

/*
** Do not include any of the File I/O interface procedures if the
** SQLITE_OMIT_DISKIO macro is defined (indicating that the database
** will be in-memory only)
*/
#ifndef SQLITE_OMIT_DISKIO

/*
** Define various macros that are missing from some systems.
*/
#ifndef O_LARGEFILE
# define O_LARGEFILE 0
#endif
#ifdef SQLITE_DISABLE_LFS
................................................................................

  pNew->pMethod = &sqlite3UnixIoMethod;
  OpenCounter(+1);
  return SQLITE_OK;
}
#endif /* SQLITE_ENABLE_LOCKING_STYLE */

#endif /* SQLITE_OMIT_DISKIO */
/***************************************************************************
** Everything above deals with file I/O.  Everything that follows deals
** with other miscellanous aspects of the operating system interface
****************************************************************************/

/*
** Open a file descriptor to the directory containing file zFilename.
** If successful, *pFd is set to the opened file descriptor and
** SQLITE_OK is returned. If an error occurs, either SQLITE_NOMEM
** or SQLITE_CANTOPEN is returned and *pFd is set to an undefined
** value.
**
................................................................................
** the file descriptor *pFd using close().
*/
static int openDirectory(const char *zFilename, int *pFd){
  int ii;
  int fd;
  char zDirname[MAX_PATHNAME+1];

  strncpy(zDirname, zFilename, MAX_PATHNAME);
  zDirname[MAX_PATHNAME-1] = '\0';
  for(ii=strlen(zDirname); ii>=0 && zDirname[ii]!='/'; ii--);
  if( ii>0 ){
    zDirname[ii] = '\0';
    fd = open(zDirname, O_RDONLY|O_BINARY, 0);
    if( fd>0 ){
#ifdef FD_CLOEXEC
      fcntl(fd, F_SETFD, fcntl(fd, F_GETFD, 0) | FD_CLOEXEC);
................................................................................
** The old OpenExclusive() accepted a boolean argument - "delFlag". If
** true, the file was configured to be automatically deleted when the
** file handle closed. To achieve the same effect using this new 
** interface, add the DELETEONCLOSE flag to those specified above for 
** OpenExclusive().
*/
static int unixOpen(
  void *pNotUsed, 
  const char *zPath, 
  sqlite3_file *pFile,
  int flags,
  int *pOutFlags
){
  int fd = 0;                    /* File descriptor returned by open() */
  int dirfd = -1;                /* Directory file descriptor */
................................................................................

  memset(pFile, 0, sizeof(unixFile));
  fd = open(zPath, oflags, isDelete?0600:SQLITE_DEFAULT_FILE_PERMISSIONS);
  if( fd<0 && isReadWrite && !isExclusive ){
    /* Failed to open the file for read/write access. Try read-only. */
    flags &= ~(SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE);
    flags |= SQLITE_OPEN_READONLY;
    return unixOpen(pNotUsed, zPath, pFile, flags, pOutFlags);
  }
  if( fd<0 ){
    return SQLITE_CANTOPEN;
  }
  if( isDelete ){
    unlink(zPath);
  }
................................................................................
  return fillInUnixFile(fd, dirfd, pFile, zPath);
}

/*
** Delete the file at zPath. If the dirSync argument is true, fsync()
** the directory after deleting the file.
*/
static int unixDelete(void *pNotUsed, const char *zPath, int dirSync){
  int rc = SQLITE_OK;
  SimulateIOError(return SQLITE_IOERR_DELETE);
  unlink(zPath);
  if( dirSync ){
    int fd;
    rc = openDirectory(zPath, &fd);
    if( rc==SQLITE_OK ){
................................................................................
**
**     SQLITE_ACCESS_EXISTS: Return 1 if the file exists
**     SQLITE_ACCESS_READWRITE: Return 1 if the file is read and writable.
**     SQLITE_ACCESS_READONLY: Return 1 if the file is readable.
**
** Otherwise return 0.
*/
static int unixAccess(void *pNotUsed, const char *zPath, int flags){
  int amode;
  switch( flags ){
    case SQLITE_ACCESS_EXISTS:
      amode = F_OK;
      break;
    case SQLITE_ACCESS_READWRITE:
      amode = W_OK|R_OK;
................................................................................
    default:
      assert(!"Invalid flags argument");
  }
  return (access(zPath, amode)==0);
}

/*
** Create a temporary file name in zBuf.  zBuf must be big enough to
** hold at least MAX_PATHNAME characters.

*/
static int unixGetTempName(void *pNotUsed, char *zBuf){
  static const char *azDirs[] = {
     0,
     "/var/tmp",
     "/usr/tmp",
     "/tmp",
     ".",
  };
................................................................................
    if( stat(azDirs[i], &buf) ) continue;
    if( !S_ISDIR(buf.st_mode) ) continue;
    if( access(azDirs[i], 07) ) continue;
    zDir = azDirs[i];
    break;
  }
  do{

    sqlite3_snprintf(MAX_PATHNAME-17, zBuf, "%s/"TEMP_FILE_PREFIX, zDir);
    j = strlen(zBuf);
    sqlite3Randomness(15, &zBuf[j]);
    for(i=0; i<15; i++, j++){
      zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
    }
    zBuf[j] = 0;
  }while( access(zBuf,0)==0 );
................................................................................
** is stored as a nul-terminated string in the buffer pointed to by
** zPath. 
**
** zOut points to a buffer of at least sqlite3_vfs.mxPathname bytes 
** (in this case, MAX_PATHNAME bytes). The full-path is written to
** this buffer before returning.
*/
static int unixFullPathname(void *pNotUsed, const char *zPath, char *zOut){

  zOut[MAX_PATHNAME-1] = '\0';
  if( zPath[0]=='/' ){
    strncpy(zOut, zPath, MAX_PATHNAME-1);

  }else{
    int nCwd;
    if( getcwd(zOut, MAX_PATHNAME-1)==0 ){
      return SQLITE_ERROR;
    }
    nCwd = strlen(zOut);
    zOut[nCwd] = '/';
    strncpy(&zOut[nCwd+1], zPath, MAX_PATHNAME-1-nCwd-1);
  }
  return SQLITE_OK;

#if 0
  /*
  ** Remove "/./" path elements and convert "/A/./" path elements
  ** to just "/".
................................................................................

#ifndef SQLITE_OMIT_LOAD_EXTENSION
/*
** Interfaces for opening a shared library, finding entry points
** within the shared library, and closing the shared library.
*/
#include <dlfcn.h>
static void *unixDlOpen(void *pNotUsed, const char *zFilename){
  return dlopen(zFilename, RTLD_NOW | RTLD_GLOBAL);
}
static void unixDlError(void *pNotUsed, int nBuf, char *zBufOut){
  char *zErr;
  enterMutex();
  zErr = dlerror();
  if( zErr ){
    strncpy(zBufOut, zErr, nBuf-1);
    zBufOut[nBuf-1] = '\0';
  }else if(nBuf>0) {
    zBufOut[0] = '\0';
  }
  leaveMutex();
}
void *unixDlSym(void *pHandle, const char *zSymbol){
  return dlsym(pHandle, zSymbol);
}
void unixDlClose(void *pHandle){
  dlclose(pHandle);
}
#else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
  #define unixDlOpen  0
  #define unixDlError 0
  #define unixDlSym   0
  #define unixDlClose 0
#endif

/*
** Write nBuf bytes of random data to the supplied buffer zBuf.
*/
static int unixRandomness(void *pNotUsed, int nBuf, char *zBuf){

  assert(nBuf>=(sizeof(time_t)+sizeof(int)));

  /* We have to initialize zBuf to prevent valgrind from reporting
  ** errors.  The reports issued by valgrind are incorrect - we would
  ** prefer that the randomness be increased by making use of the
  ** uninitialized space in zBuf - but valgrind errors tend to worry
................................................................................
** Sleep for a little while.  Return the amount of time slept.
** The argument is the number of microseconds we want to sleep.
** The return value is the number of microseconds of sleep actually
** requested from the underlying operating system, a number which
** might be greater than or equal to the argument, but not less
** than the argument.
*/
static int unixSleep(void *pNotUsed, int microseconds){
#if defined(HAVE_USLEEP) && HAVE_USLEEP
  usleep(microseconds);
  return microseconds;
#else
  int seconds = (microseconds+999999)/1000000;
  sleep(seconds);
  return seconds*1000000;
................................................................................
#endif

/*
** Find the current time (in Universal Coordinated Time).  Write the
** current time and date as a Julian Day number into *prNow and
** return 0.  Return 1 if the time and date cannot be found.
*/
static int unixCurrentTime(void *pNotUsed, double *prNow){
#ifdef NO_GETTOD
  time_t t;
  time(&t);
  *prNow = t/86400.0 + 2440587.5;
#else
  struct timeval sNow;
  gettimeofday(&sNow, 0);
................................................................................
  if( sqlite3_current_time ){
    *prNow = sqlite3_current_time/86400.0 + 2440587.5;
  }
#endif
  return 0;
}









sqlite3_vfs sqlite3DefaultVfs = {
  1,                  /* iVersion */
  sizeof(unixFile),   /* szOsFile */
  MAX_PATHNAME,       /* mxPathname */
  0,                  /* nRef */
  0,                  /* vfsMutex */
  0,                  /* pNext */
  "unix",             /* zName */
  0,                  /* pAppData */

  unixOpen,           /* xOpen */
  unixDelete,         /* xDelete */
  unixAccess,         /* xAccess */
  unixGetTempName,    /* xGetTempName */
  unixFullPathname,   /* xFullPathname */
  unixDlOpen,         /* xDlOpen */
  unixDlError,        /* xDlError */
  unixDlSym,          /* xDlSym */
  unixDlClose,        /* xDlClose */
  unixRandomness,     /* xRandomness */
  unixSleep,          /* xSleep */
  unixCurrentTime     /* xCurrentTime */
};
 



#endif /* OS_UNIX */

};

/*
** Include code that is common to all os_*.c files
*/
#include "os_common.h"








/*
** Define various macros that are missing from some systems.
*/
#ifndef O_LARGEFILE
# define O_LARGEFILE 0
#endif
#ifdef SQLITE_DISABLE_LFS
................................................................................

  pNew->pMethod = &sqlite3UnixIoMethod;
  OpenCounter(+1);
  return SQLITE_OK;
}
#endif /* SQLITE_ENABLE_LOCKING_STYLE */







/*
** Open a file descriptor to the directory containing file zFilename.
** If successful, *pFd is set to the opened file descriptor and
** SQLITE_OK is returned. If an error occurs, either SQLITE_NOMEM
** or SQLITE_CANTOPEN is returned and *pFd is set to an undefined
** value.
**
................................................................................
** the file descriptor *pFd using close().
*/
static int openDirectory(const char *zFilename, int *pFd){
  int ii;
  int fd;
  char zDirname[MAX_PATHNAME+1];

  sqlite3_snprintf(MAX_PATHNAME, zDirname, "%s", zFilename);

  for(ii=strlen(zDirname); ii>=0 && zDirname[ii]!='/'; ii--);
  if( ii>0 ){
    zDirname[ii] = '\0';
    fd = open(zDirname, O_RDONLY|O_BINARY, 0);
    if( fd>0 ){
#ifdef FD_CLOEXEC
      fcntl(fd, F_SETFD, fcntl(fd, F_GETFD, 0) | FD_CLOEXEC);
................................................................................
** The old OpenExclusive() accepted a boolean argument - "delFlag". If
** true, the file was configured to be automatically deleted when the
** file handle closed. To achieve the same effect using this new 
** interface, add the DELETEONCLOSE flag to those specified above for 
** OpenExclusive().
*/
static int unixOpen(
  sqlite3_vfs *pVfs, 
  const char *zPath, 
  sqlite3_file *pFile,
  int flags,
  int *pOutFlags
){
  int fd = 0;                    /* File descriptor returned by open() */
  int dirfd = -1;                /* Directory file descriptor */
................................................................................

  memset(pFile, 0, sizeof(unixFile));
  fd = open(zPath, oflags, isDelete?0600:SQLITE_DEFAULT_FILE_PERMISSIONS);
  if( fd<0 && isReadWrite && !isExclusive ){
    /* Failed to open the file for read/write access. Try read-only. */
    flags &= ~(SQLITE_OPEN_READWRITE|SQLITE_OPEN_CREATE);
    flags |= SQLITE_OPEN_READONLY;
    return unixOpen(pVfs, zPath, pFile, flags, pOutFlags);
  }
  if( fd<0 ){
    return SQLITE_CANTOPEN;
  }
  if( isDelete ){
    unlink(zPath);
  }
................................................................................
  return fillInUnixFile(fd, dirfd, pFile, zPath);
}

/*
** Delete the file at zPath. If the dirSync argument is true, fsync()
** the directory after deleting the file.
*/
static int unixDelete(sqlite3_vfs *pVfs, const char *zPath, int dirSync){
  int rc = SQLITE_OK;
  SimulateIOError(return SQLITE_IOERR_DELETE);
  unlink(zPath);
  if( dirSync ){
    int fd;
    rc = openDirectory(zPath, &fd);
    if( rc==SQLITE_OK ){
................................................................................
**
**     SQLITE_ACCESS_EXISTS: Return 1 if the file exists
**     SQLITE_ACCESS_READWRITE: Return 1 if the file is read and writable.
**     SQLITE_ACCESS_READONLY: Return 1 if the file is readable.
**
** Otherwise return 0.
*/
static int unixAccess(sqlite3_vfs *pVfs, const char *zPath, int flags){
  int amode;
  switch( flags ){
    case SQLITE_ACCESS_EXISTS:
      amode = F_OK;
      break;
    case SQLITE_ACCESS_READWRITE:
      amode = W_OK|R_OK;
................................................................................
    default:
      assert(!"Invalid flags argument");
  }
  return (access(zPath, amode)==0);
}

/*
** Create a temporary file name in zBuf.  zBuf must be allocated
** by the calling process and must be big enough to hold at least
** pVfs->mxPathname bytes.
*/
static int unixGetTempName(sqlite3_vfs *pVfs, char *zBuf){
  static const char *azDirs[] = {
     0,
     "/var/tmp",
     "/usr/tmp",
     "/tmp",
     ".",
  };
................................................................................
    if( stat(azDirs[i], &buf) ) continue;
    if( !S_ISDIR(buf.st_mode) ) continue;
    if( access(azDirs[i], 07) ) continue;
    zDir = azDirs[i];
    break;
  }
  do{
    assert( pVfs->mxPathname==MAX_PATHNAME );
    sqlite3_snprintf(MAX_PATHNAME-17, zBuf, "%s/"SQLITE_TEMP_FILE_PREFIX, zDir);
    j = strlen(zBuf);
    sqlite3Randomness(15, &zBuf[j]);
    for(i=0; i<15; i++, j++){
      zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
    }
    zBuf[j] = 0;
  }while( access(zBuf,0)==0 );
................................................................................
** is stored as a nul-terminated string in the buffer pointed to by
** zPath. 
**
** zOut points to a buffer of at least sqlite3_vfs.mxPathname bytes 
** (in this case, MAX_PATHNAME bytes). The full-path is written to
** this buffer before returning.
*/
static int unixFullPathname(sqlite3_vfs *pVfs, const char *zPath, char *zOut){
  assert( pVfs->mxPathname==MAX_PATHNAME );
  zOut[MAX_PATHNAME-1] = '\0';
  if( zPath[0]=='/' ){

    sqlite3_snprintf(MAX_PATHNAME, zOut, "%s", zPath);
  }else{
    int nCwd;
    if( getcwd(zOut, MAX_PATHNAME-1)==0 ){
      return SQLITE_ERROR;
    }
    nCwd = strlen(zOut);
    sqlite3_snprintf(MAX_PATHNAME-nCwd, &zOut[nCwd], "/%s", zPath);

  }
  return SQLITE_OK;

#if 0
  /*
  ** Remove "/./" path elements and convert "/A/./" path elements
  ** to just "/".
................................................................................

#ifndef SQLITE_OMIT_LOAD_EXTENSION
/*
** Interfaces for opening a shared library, finding entry points
** within the shared library, and closing the shared library.
*/
#include <dlfcn.h>
static void *unixDlOpen(sqlite3_vfs *pVfs, const char *zFilename){
  return dlopen(zFilename, RTLD_NOW | RTLD_GLOBAL);
}
static void unixDlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){
  char *zErr;
  enterMutex();
  zErr = dlerror();
  if( zErr ){
    sqlite3_snprintf(nBuf, zBufOut, "%s", zErr);

  }else if(nBuf>0) {
    zBufOut[0] = '\0';
  }
  leaveMutex();
}
void *unixDlSym(sqlite3_vfs *pVfs, void *pHandle, const char *zSymbol){
  return dlsym(pHandle, zSymbol);
}
void unixDlClose(sqlite3_vfs *pVfs, void *pHandle){
  dlclose(pHandle);
}
#else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
  #define unixDlOpen  0
  #define unixDlError 0
  #define unixDlSym   0
  #define unixDlClose 0
#endif

/*
** Write nBuf bytes of random data to the supplied buffer zBuf.
*/
static int unixRandomness(sqlite3_vfs *pVfs, int nBuf, char *zBuf){

  assert(nBuf>=(sizeof(time_t)+sizeof(int)));

  /* We have to initialize zBuf to prevent valgrind from reporting
  ** errors.  The reports issued by valgrind are incorrect - we would
  ** prefer that the randomness be increased by making use of the
  ** uninitialized space in zBuf - but valgrind errors tend to worry
................................................................................
** Sleep for a little while.  Return the amount of time slept.
** The argument is the number of microseconds we want to sleep.
** The return value is the number of microseconds of sleep actually
** requested from the underlying operating system, a number which
** might be greater than or equal to the argument, but not less
** than the argument.
*/
static int unixSleep(sqlite3_vfs *pVfs, int microseconds){
#if defined(HAVE_USLEEP) && HAVE_USLEEP
  usleep(microseconds);
  return microseconds;
#else
  int seconds = (microseconds+999999)/1000000;
  sleep(seconds);
  return seconds*1000000;
................................................................................
#endif

/*
** Find the current time (in Universal Coordinated Time).  Write the
** current time and date as a Julian Day number into *prNow and
** return 0.  Return 1 if the time and date cannot be found.
*/
static int unixCurrentTime(sqlite3_vfs *pVfs, double *prNow){
#ifdef NO_GETTOD
  time_t t;
  time(&t);
  *prNow = t/86400.0 + 2440587.5;
#else
  struct timeval sNow;
  gettimeofday(&sNow, 0);
................................................................................
  if( sqlite3_current_time ){
    *prNow = sqlite3_current_time/86400.0 + 2440587.5;
  }
#endif
  return 0;
}


/*
** Return a pointer to the sqlite3DefaultVfs structure.   We use
** a function rather than give the structure global scope because
** some compilers (MSVC) do not allow forward declarations of
** initialized structures.
*/
sqlite3_vfs *sqlite3OsDefaultVfs(void){
  static sqlite3_vfs unixVfs = {
    1,                  /* iVersion */
    sizeof(unixFile),   /* szOsFile */
    MAX_PATHNAME,       /* mxPathname */
    0,                  /* nRef */
    0,                  /* vfsMutex */
    0,                  /* pNext */
    "unix",             /* zName */
    0,                  /* pAppData */
  
    unixOpen,           /* xOpen */
    unixDelete,         /* xDelete */
    unixAccess,         /* xAccess */
    unixGetTempName,    /* xGetTempName */
    unixFullPathname,   /* xFullPathname */
    unixDlOpen,         /* xDlOpen */
    unixDlError,        /* xDlError */
    unixDlSym,          /* xDlSym */
    unixDlClose,        /* xDlClose */
    unixRandomness,     /* xRandomness */
    unixSleep,          /* xSleep */
    unixCurrentTime     /* xCurrentTime */
  };
  
  return &unixVfs;
}
 
#endif /* OS_UNIX */

  BOOL bPending;      /* Indicates a pending lock has been obtained */
  BOOL bReserved;     /* Indicates a reserved lock has been obtained */
  BOOL bExclusive;    /* Indicates an exclusive lock has been obtained */
} winceLock;
#endif

/*
** The winFile structure is a subclass of OsFile specific to the win32
** portability layer.
*/
typedef struct winFile winFile;
struct winFile {
  IoMethod const *pMethod;/* Must be first */
  HANDLE h;               /* Handle for accessing the file */
  unsigned char locktype; /* Type of lock currently held on this file */
  short sharedLockByte;   /* Randomly chosen byte used as a shared lock */
#if OS_WINCE
  WCHAR *zDeleteOnClose;  /* Name of file to delete when closing */
  HANDLE hMutex;          /* Mutex used to control access to shared lock */  
  HANDLE hShared;         /* Shared memory segment used for locking */
  winceLock local;        /* Locks obtained by this instance of winFile */
  winceLock *shared;      /* Global shared lock memory for the file  */
#endif
};


/*
** Do not include any of the File I/O interface procedures if the
** SQLITE_OMIT_DISKIO macro is defined (indicating that there database
** will be in-memory only)
*/
#ifndef SQLITE_OMIT_DISKIO

/*
** The following variable is (normally) set once and never changes
** thereafter.  It records whether the operating system is Win95
** or WinNT.
**
** 0:   Operating system unknown.
** 1:   Operating system is Win95.
** 2:   Operating system is WinNT.
**
** In order to facilitate testing on a WinNT system, the test fixture
** can manually set this value to 1 to emulate Win98 behavior.
*/

int sqlite3_os_type = 0;




/*
** Return true (non-zero) if we are running under WinNT, Win2K, WinXP,
** or WinCE.  Return false (zero) for Win95, Win98, or WinME.
**
** Here is an interesting observation:  Win95, Win98, and WinME lack
** the LockFileEx() API.  But we can still statically link against that
................................................................................
    return sqlite3_os_type==2;
  }
#endif /* OS_WINCE */

/*
** Convert a UTF-8 string to microsoft unicode (UTF-16?). 
**
** Space to hold the returned string is obtained from sqliteMalloc.
*/
static WCHAR *utf8ToUnicode(const char *zFilename){
  int nChar;
  WCHAR *zWideFilename;

  nChar = MultiByteToWideChar(CP_UTF8, 0, zFilename, -1, NULL, 0);
  zWideFilename = sqliteMalloc( nChar*sizeof(zWideFilename[0]) );
  if( zWideFilename==0 ){
    return 0;
  }
  nChar = MultiByteToWideChar(CP_UTF8, 0, zFilename, -1, zWideFilename, nChar);
  if( nChar==0 ){
    sqliteFree(zWideFilename);
    zWideFilename = 0;
  }
  return zWideFilename;
}

/*
** Convert microsoft unicode to UTF-8.  Space to hold the returned string is
** obtained from sqliteMalloc().
*/
static char *unicodeToUtf8(const WCHAR *zWideFilename){
  int nByte;
  char *zFilename;

  nByte = WideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, 0, 0, 0, 0);
  zFilename = sqliteMalloc( nByte );
  if( zFilename==0 ){
    return 0;
  }
  nByte = WideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, zFilename, nByte,
                              0, 0);
  if( nByte == 0 ){
    sqliteFree(zFilename);
    zFilename = 0;
  }
  return zFilename;
}

/*
** Convert an ansi string to microsoft unicode, based on the
** current codepage settings for file apis.
** 
** Space to hold the returned string is obtained
** from sqliteMalloc.
*/
static WCHAR *mbcsToUnicode(const char *zFilename){
  int nByte;
  WCHAR *zMbcsFilename;
  int codepage = AreFileApisANSI() ? CP_ACP : CP_OEMCP;

  nByte = MultiByteToWideChar(codepage, 0, zFilename, -1, NULL,0)*sizeof(WCHAR);
  zMbcsFilename = sqliteMalloc( nByte*sizeof(zMbcsFilename[0]) );
  if( zMbcsFilename==0 ){
    return 0;
  }
  nByte = MultiByteToWideChar(codepage, 0, zFilename, -1, zMbcsFilename, nByte);
  if( nByte==0 ){
    sqliteFree(zMbcsFilename);
    zMbcsFilename = 0;
  }
  return zMbcsFilename;
}

/*
** Convert microsoft unicode to multibyte character string, based on the
** user's Ansi codepage.
**
** Space to hold the returned string is obtained from
** sqliteMalloc().
*/
static char *unicodeToMbcs(const WCHAR *zWideFilename){
  int nByte;
  char *zFilename;
  int codepage = AreFileApisANSI() ? CP_ACP : CP_OEMCP;

  nByte = WideCharToMultiByte(codepage, 0, zWideFilename, -1, 0, 0, 0, 0);
  zFilename = sqliteMalloc( nByte );
  if( zFilename==0 ){
    return 0;
  }
  nByte = WideCharToMultiByte(codepage, 0, zWideFilename, -1, zFilename, nByte,
                              0, 0);
  if( nByte == 0 ){
    sqliteFree(zFilename);
    zFilename = 0;
  }
  return zFilename;
}

/*
** Convert multibyte character string to UTF-8.  Space to hold the
** returned string is obtained from sqliteMalloc().
*/
static char *mbcsToUtf8(const char *zFilename){
  char *zFilenameUtf8;
  WCHAR *zTmpWide;

  zTmpWide = mbcsToUnicode(zFilename);
  if( zTmpWide==0 ){
    return 0;
  }
  zFilenameUtf8 = unicodeToUtf8(zTmpWide);
  sqliteFree(zTmpWide);
  return zFilenameUtf8;
}

/*
** Convert UTF-8 to multibyte character string.  Space to hold the 
** returned string is obtained from sqliteMalloc().
*/
static char *utf8ToMbcs(const char *zFilename){
  char *zFilenameMbcs;
  WCHAR *zTmpWide;

  zTmpWide = utf8ToUnicode(zFilename);
  if( zTmpWide==0 ){
    return 0;
  }
  zFilenameMbcs = unicodeToMbcs(zTmpWide);
  sqliteFree(zTmpWide);
  return zFilenameMbcs;
}

#if OS_WINCE
/*************************************************************************
** This section contains code for WinCE only.
*/
................................................................................
  for (;*zTok;zTok++){
    if (*zTok == '\\') *zTok = '_';
  }

  /* Create/open the named mutex */
  pFile->hMutex = CreateMutexW(NULL, FALSE, zName);
  if (!pFile->hMutex){
    sqliteFree(zName);
    return FALSE;
  }

  /* Acquire the mutex before continuing */
  winceMutexAcquire(pFile->hMutex);
  
  /* Since the names of named mutexes, semaphores, file mappings etc are 
................................................................................

  /* Set a flag that indicates we're the first to create the memory so it 
  ** must be zero-initialized */
  if (GetLastError() == ERROR_ALREADY_EXISTS){
    bInit = FALSE;
  }

  sqliteFree(zName);

  /* If we succeeded in making the shared memory handle, map it. */
  if (pFile->hShared){
    pFile->shared = (winceLock*)MapViewOfFile(pFile->hShared, 
             FILE_MAP_READ|FILE_MAP_WRITE, 0, 0, sizeof(winceLock));
    /* If mapping failed, close the shared memory handle and erase it */
    if (!pFile->shared){
................................................................................

    /* De-reference and close our copy of the shared memory handle */
    UnmapViewOfFile(pFile->shared);
    CloseHandle(pFile->hShared);

    if( pFile->zDeleteOnClose ){
      DeleteFileW(pFile->zDeleteOnClose);
      sqliteFree(pFile->zDeleteOnClose);
      pFile->zDeleteOnClose = 0;
    }

    /* Done with the mutex */
    winceMutexRelease(pFile->hMutex);    
    CloseHandle(pFile->hMutex);
    pFile->hMutex = NULL;
................................................................................
  return FALSE;
}
/*
** End of the special code for wince
*****************************************************************************/
#endif /* OS_WINCE */

/*
** Convert a UTF-8 filename into whatever form the underlying
** operating system wants filenames in.  Space to hold the result
** is obtained from sqliteMalloc and must be freed by the calling
** function.
*/
static void *convertUtf8Filename(const char *zFilename){
  void *zConverted = 0;
  if( isNT() ){
    zConverted = utf8ToUnicode(zFilename);
  }else{
    zConverted = utf8ToMbcs(zFilename);
  }
  /* caller will handle out of memory */
  return zConverted;
}

/*
** Delete the named file.
**
** Note that windows does not allow a file to be deleted if some other
** process has it open.  Sometimes a virus scanner or indexing program
** will open a journal file shortly after it is created in order to do
** whatever it is it does.  While this other process is holding the
** file open, we will be unable to delete it.  To work around this
** problem, we delay 100 milliseconds and try to delete again.  Up
** to MX_DELETION_ATTEMPTs deletion attempts are run before giving
** up and returning an error.
*/
#define MX_DELETION_ATTEMPTS 3
int sqlite3WinDelete(const char *zFilename){
  int cnt = 0;
  int rc;
  void *zConverted = convertUtf8Filename(zFilename);
  if( zConverted==0 ){
    return SQLITE_NOMEM;
  }
  SimulateIOError(return SQLITE_IOERR_DELETE);
  if( isNT() ){
    do{
      rc = DeleteFileW(zConverted);
    }while( rc==0 && GetFileAttributesW(zConverted)!=0xffffffff 
            && cnt++ < MX_DELETION_ATTEMPTS && (Sleep(100), 1) );
  }else{
#if OS_WINCE
    return SQLITE_NOMEM;
#else
    do{
      rc = DeleteFileA(zConverted);
    }while( rc==0 && GetFileAttributesA(zConverted)!=0xffffffff
            && cnt++ < MX_DELETION_ATTEMPTS && (Sleep(100), 1) );
#endif
  }
  sqliteFree(zConverted);
  OSTRACE2("DELETE \"%s\"\n", zFilename);
  return rc!=0 ? SQLITE_OK : SQLITE_IOERR;
}

/*
** Return TRUE if the named file exists.
*/
int sqlite3WinFileExists(const char *zFilename){
  int exists = 0;
  void *zConverted = convertUtf8Filename(zFilename);
  if( zConverted==0 ){
    return SQLITE_NOMEM;
  }
  if( isNT() ){
    exists = GetFileAttributesW((WCHAR*)zConverted) != 0xffffffff;
  }else{
#if OS_WINCE
    return SQLITE_NOMEM;
#else
    exists = GetFileAttributesA((char*)zConverted) != 0xffffffff;
#endif
  }
  sqliteFree(zConverted);
  return exists;
}

/* Forward declaration */
static int allocateWinFile(winFile *pInit, OsFile **pId);

/*
** Attempt to open a file for both reading and writing.  If that
** fails, try opening it read-only.  If the file does not exist,
** try to create it.
**
** On success, a handle for the open file is written to *id
** and *pReadonly is set to 0 if the file was opened for reading and
** writing or 1 if the file was opened read-only.  The function returns
** SQLITE_OK.
**
** On failure, the function returns SQLITE_CANTOPEN and leaves
** *id and *pReadonly unchanged.
*/
int sqlite3WinOpenReadWrite(
  const char *zFilename,
  OsFile **pId,
  int *pReadonly
){
  winFile f;
  HANDLE h;
  void *zConverted = convertUtf8Filename(zFilename);
  if( zConverted==0 ){
    return SQLITE_NOMEM;
  }
  assert( *pId==0 );

  if( isNT() ){
    h = CreateFileW((WCHAR*)zConverted,
       GENERIC_READ | GENERIC_WRITE,
       FILE_SHARE_READ | FILE_SHARE_WRITE,
       NULL,
       OPEN_ALWAYS,
       FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS,
       NULL
    );
    if( h==INVALID_HANDLE_VALUE ){
      h = CreateFileW((WCHAR*)zConverted,
         GENERIC_READ,
         FILE_SHARE_READ | FILE_SHARE_WRITE,
         NULL,
         OPEN_ALWAYS,
         FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS,
         NULL
      );
      if( h==INVALID_HANDLE_VALUE ){
        sqliteFree(zConverted);
        return SQLITE_CANTOPEN;
      }
      *pReadonly = 1;
    }else{
      *pReadonly = 0;
    }
#if OS_WINCE
    if (!winceCreateLock(zFilename, &f)){
      CloseHandle(h);
      sqliteFree(zConverted);
      return SQLITE_CANTOPEN;
    }
#endif
  }else{
#if OS_WINCE
    return SQLITE_NOMEM;
#else
    h = CreateFileA((char*)zConverted,
       GENERIC_READ | GENERIC_WRITE,
       FILE_SHARE_READ | FILE_SHARE_WRITE,
       NULL,
       OPEN_ALWAYS,
       FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS,
       NULL
    );
    if( h==INVALID_HANDLE_VALUE ){
      h = CreateFileA((char*)zConverted,
         GENERIC_READ,
         FILE_SHARE_READ | FILE_SHARE_WRITE,
         NULL,
         OPEN_ALWAYS,
         FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS,
         NULL
      );
      if( h==INVALID_HANDLE_VALUE ){
        sqliteFree(zConverted);
        return SQLITE_CANTOPEN;
      }
      *pReadonly = 1;
    }else{
      *pReadonly = 0;
    }
#endif /* OS_WINCE */
  }

  sqliteFree(zConverted);

  f.h = h;
#if OS_WINCE
  f.zDeleteOnClose = 0;
#endif
  OSTRACE3("OPEN R/W %d \"%s\"\n", h, zFilename);
  return allocateWinFile(&f, pId);
}


/*
** Attempt to open a new file for exclusive access by this process.
** The file will be opened for both reading and writing.  To avoid
** a potential security problem, we do not allow the file to have
** previously existed.  Nor do we allow the file to be a symbolic
** link.
**
** If delFlag is true, then make arrangements to automatically delete
** the file when it is closed.
**
** On success, write the file handle into *id and return SQLITE_OK.
**
** On failure, return SQLITE_CANTOPEN.
**
** Sometimes if we have just deleted a prior journal file, windows
** will fail to open a new one because there is a "pending delete".
** To work around this bug, we pause for 100 milliseconds and attempt
** a second open after the first one fails.  The whole operation only
** fails if both open attempts are unsuccessful.
*/
int sqlite3WinOpenExclusive(const char *zFilename, OsFile **pId, int delFlag){
  winFile f;
  HANDLE h;
  DWORD fileflags;
  void *zConverted = convertUtf8Filename(zFilename);
  if( zConverted==0 ){
    return SQLITE_NOMEM;
  }
  assert( *pId == 0 );
  fileflags = FILE_FLAG_RANDOM_ACCESS;
#if !OS_WINCE
  if( delFlag ){
    fileflags |= FILE_ATTRIBUTE_TEMPORARY | FILE_FLAG_DELETE_ON_CLOSE;
  }
#endif
  if( isNT() ){
    int cnt = 0;
    do{
      h = CreateFileW((WCHAR*)zConverted,
         GENERIC_READ | GENERIC_WRITE,
         0,
         NULL,
         CREATE_ALWAYS,
         fileflags,
         NULL
      );
    }while( h==INVALID_HANDLE_VALUE && cnt++ < 2 && (Sleep(100), 1) );
  }else{
#if OS_WINCE
    return SQLITE_NOMEM;
#else
    int cnt = 0;
    do{
      h = CreateFileA((char*)zConverted,
        GENERIC_READ | GENERIC_WRITE,
        0,
        NULL,
        CREATE_ALWAYS,
        fileflags,
        NULL
      );
    }while( h==INVALID_HANDLE_VALUE && cnt++ < 2 && (Sleep(100), 1) );
#endif /* OS_WINCE */
  }
#if OS_WINCE
  if( delFlag && h!=INVALID_HANDLE_VALUE ){
    f.zDeleteOnClose = zConverted;
    zConverted = 0;
  }
  f.hMutex = NULL;
#endif
  sqliteFree(zConverted);
  if( h==INVALID_HANDLE_VALUE ){
    return SQLITE_CANTOPEN;
  }
  f.h = h;
  OSTRACE3("OPEN EX %d \"%s\"\n", h, zFilename);
  return allocateWinFile(&f, pId);
}

/*
** Attempt to open a new file for read-only access.
**
** On success, write the file handle into *id and return SQLITE_OK.
**
** On failure, return SQLITE_CANTOPEN.
*/
int sqlite3WinOpenReadOnly(const char *zFilename, OsFile **pId){
  winFile f;
  HANDLE h;
  void *zConverted = convertUtf8Filename(zFilename);
  if( zConverted==0 ){
    return SQLITE_NOMEM;
  }
  assert( *pId==0 );
  if( isNT() ){
    h = CreateFileW((WCHAR*)zConverted,
       GENERIC_READ,
       0,
       NULL,
       OPEN_EXISTING,
       FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS,
       NULL
    );
  }else{
#if OS_WINCE
    return SQLITE_NOMEM;
#else
    h = CreateFileA((char*)zConverted,
       GENERIC_READ,
       0,
       NULL,
       OPEN_EXISTING,
       FILE_ATTRIBUTE_NORMAL | FILE_FLAG_RANDOM_ACCESS,
       NULL
    );
#endif
  }
  sqliteFree(zConverted);
  if( h==INVALID_HANDLE_VALUE ){
    return SQLITE_CANTOPEN;
  }
  f.h = h;
#if OS_WINCE
  f.zDeleteOnClose = 0;
  f.hMutex = NULL;
#endif
  OSTRACE3("OPEN RO %d \"%s\"\n", h, zFilename);
  return allocateWinFile(&f, pId);
}

/*
** Attempt to open a file descriptor for the directory that contains a
** file.  This file descriptor can be used to fsync() the directory
** in order to make sure the creation of a new file is actually written
** to disk.
**
** This routine is only meaningful for Unix.  It is a no-op under
** windows since windows does not support hard links.
**
** On success, a handle for a previously open file is at *id is
** updated with the new directory file descriptor and SQLITE_OK is
** returned.
**
** On failure, the function returns SQLITE_CANTOPEN and leaves
** *id unchanged.
*/
static int winOpenDirectory(
  OsFile *id,
  const char *zDirname
){
  return SQLITE_OK;
}

/*
** Create a temporary file name in zBuf.  zBuf must be big enough to
** hold at least SQLITE_TEMPNAME_SIZE characters.
*/
int sqlite3WinTempFileName(char *zBuf){
  static char zChars[] =
    "abcdefghijklmnopqrstuvwxyz"
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    "0123456789";
  int i, j;
  char zTempPath[SQLITE_TEMPNAME_SIZE];
  if( sqlite3_temp_directory ){
    strncpy(zTempPath, sqlite3_temp_directory, SQLITE_TEMPNAME_SIZE-30);
    zTempPath[SQLITE_TEMPNAME_SIZE-30] = 0;
  }else if( isNT() ){
    char *zMulti;
    WCHAR zWidePath[SQLITE_TEMPNAME_SIZE];
    GetTempPathW(SQLITE_TEMPNAME_SIZE-30, zWidePath);
    zMulti = unicodeToUtf8(zWidePath);
    if( zMulti ){
      strncpy(zTempPath, zMulti, SQLITE_TEMPNAME_SIZE-30);
      zTempPath[SQLITE_TEMPNAME_SIZE-30] = 0;
      sqliteFree(zMulti);
    }else{
      return SQLITE_NOMEM;
    }
  }else{
    char *zUtf8;
    char zMbcsPath[SQLITE_TEMPNAME_SIZE];
    GetTempPathA(SQLITE_TEMPNAME_SIZE-30, zMbcsPath);
    zUtf8 = mbcsToUtf8(zMbcsPath);
    if( zUtf8 ){
      strncpy(zTempPath, zUtf8, SQLITE_TEMPNAME_SIZE-30);
      zTempPath[SQLITE_TEMPNAME_SIZE-30] = 0;
      sqliteFree(zUtf8);
    }else{
      return SQLITE_NOMEM;
    }
  }
  for(i=strlen(zTempPath); i>0 && zTempPath[i-1]=='\\'; i--){}
  zTempPath[i] = 0;
  for(;;){
    sqlite3_snprintf(SQLITE_TEMPNAME_SIZE, zBuf,
                     "%s\\"TEMP_FILE_PREFIX, zTempPath);
    j = strlen(zBuf);
    sqlite3Randomness(15, &zBuf[j]);
    for(i=0; i<15; i++, j++){
      zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
    }
    zBuf[j] = 0;
    if( !sqlite3OsFileExists(zBuf) ) break;
  }
  OSTRACE2("TEMP FILENAME: %s\n", zBuf);
  return SQLITE_OK; 
}

/*
** Close a file.
**
** It is reported that an attempt to close a handle might sometimes
** fail.  This is a very unreasonable result, but windows is notorious
** for being unreasonable so I do not doubt that it might happen.  If
** the close fails, we pause for 100 milliseconds and try again.  As
** many as MX_CLOSE_ATTEMPT attempts to close the handle are made before
** giving up and returning an error.
*/
#define MX_CLOSE_ATTEMPT 3
static int winClose(OsFile **pId){
  winFile *pFile;
  int rc = 1;
  if( pId && (pFile = (winFile*)*pId)!=0 ){
    int rc, cnt = 0;

    OSTRACE2("CLOSE %d\n", pFile->h);
    do{
      rc = CloseHandle(pFile->h);
    }while( rc==0 && cnt++ < MX_CLOSE_ATTEMPT && (Sleep(100), 1) );
#if OS_WINCE
    winceDestroyLock(pFile);
#endif
    OpenCounter(-1);
    sqliteFree(pFile);
    *pId = 0;
  }
  return rc ? SQLITE_OK : SQLITE_IOERR;
}








/*
** Read data from a file into a buffer.  Return SQLITE_OK if all
** bytes were read successfully and SQLITE_IOERR if anything goes
** wrong.
*/
static int winRead(OsFile *id, void *pBuf, int amt){








  DWORD got;

  assert( id!=0 );
  SimulateIOError(return SQLITE_IOERR_READ);
  OSTRACE3("READ %d lock=%d\n", ((winFile*)id)->h, ((winFile*)id)->locktype);




  if( !ReadFile(((winFile*)id)->h, pBuf, amt, &got, 0) ){
    return SQLITE_IOERR_READ;
  }
  if( got==(DWORD)amt ){
    return SQLITE_OK;
  }else{
    memset(&((char*)pBuf)[got], 0, amt-got);
    return SQLITE_IOERR_SHORT_READ;
................................................................................
  }
}

/*
** Write data from a buffer into a file.  Return SQLITE_OK on success
** or some other error code on failure.
*/
static int winWrite(OsFile *id, const void *pBuf, int amt){
  int rc = 0;







  DWORD wrote;

  assert( id!=0 );
  SimulateIOError(return SQLITE_IOERR_READ);
  SimulateDiskfullError(return SQLITE_FULL);
  OSTRACE3("WRITE %d lock=%d\n", ((winFile*)id)->h, ((winFile*)id)->locktype);




  assert( amt>0 );


  while( amt>0 && (rc = WriteFile(((winFile*)id)->h, pBuf, amt, &wrote, 0))!=0
         && wrote>0 ){

    amt -= wrote;
    pBuf = &((char*)pBuf)[wrote];
  }
  if( !rc || amt>(int)wrote ){
    return SQLITE_FULL;
  }
  return SQLITE_OK;
}

/*
** Some microsoft compilers lack this definition.
*/
#ifndef INVALID_SET_FILE_POINTER
# define INVALID_SET_FILE_POINTER ((DWORD)-1)
#endif

/*
** Move the read/write pointer in a file.
*/
static int winSeek(OsFile *id, i64 offset){
  LONG upperBits = offset>>32;
  LONG lowerBits = offset & 0xffffffff;
  DWORD rc;
  assert( id!=0 );
#ifdef SQLITE_TEST


  if( offset ) SimulateDiskfullError(return SQLITE_FULL);
#endif
  rc = SetFilePointer(((winFile*)id)->h, lowerBits, &upperBits, FILE_BEGIN);
  OSTRACE3("SEEK %d %lld\n", ((winFile*)id)->h, offset);
  if( rc==INVALID_SET_FILE_POINTER && GetLastError()!=NO_ERROR ){
    return SQLITE_FULL;
  }

  return SQLITE_OK;
}

/*
** Make sure all writes to a particular file are committed to disk.
*/
static int winSync(OsFile *id, int dataOnly){
  assert( id!=0 );
  OSTRACE3("SYNC %d lock=%d\n", ((winFile*)id)->h, ((winFile*)id)->locktype);
  if( FlushFileBuffers(((winFile*)id)->h) ){
    return SQLITE_OK;
  }else{
    return SQLITE_IOERR;
  }
}

/*
** Sync the directory zDirname. This is a no-op on operating systems other
** than UNIX.
*/
int sqlite3WinSyncDirectory(const char *zDirname){
  SimulateIOError(return SQLITE_IOERR_READ);
  return SQLITE_OK;
}

/*
** Truncate an open file to a specified size
*/
static int winTruncate(OsFile *id, i64 nByte){
  LONG upperBits = nByte>>32;
  assert( id!=0 );
  OSTRACE3("TRUNCATE %d %lld\n", ((winFile*)id)->h, nByte);
  SimulateIOError(return SQLITE_IOERR_TRUNCATE);
  SetFilePointer(((winFile*)id)->h, nByte, &upperBits, FILE_BEGIN);
  SetEndOfFile(((winFile*)id)->h);
  return SQLITE_OK;
}

/*
** Determine the current size of a file in bytes
*/
static int winFileSize(OsFile *id, i64 *pSize){

  DWORD upperBits, lowerBits;
  assert( id!=0 );
  SimulateIOError(return SQLITE_IOERR_FSTAT);
  lowerBits = GetFileSize(((winFile*)id)->h, &upperBits);
  *pSize = (((i64)upperBits)<<32) + lowerBits;
  return SQLITE_OK;
}

/*
** LOCKFILE_FAIL_IMMEDIATELY is undefined on some Windows systems.
*/
#ifndef LOCKFILE_FAIL_IMMEDIATELY
................................................................................
#endif

/*
** Acquire a reader lock.
** Different API routines are called depending on whether or not this
** is Win95 or WinNT.
*/
static int getReadLock(winFile *id){
  int res;
  if( isNT() ){
    OVERLAPPED ovlp;
    ovlp.Offset = SHARED_FIRST;
    ovlp.OffsetHigh = 0;
    ovlp.hEvent = 0;
    res = LockFileEx(id->h, LOCKFILE_FAIL_IMMEDIATELY, 0, SHARED_SIZE,0,&ovlp);

  }else{
    int lk;
    sqlite3Randomness(sizeof(lk), &lk);
    id->sharedLockByte = (lk & 0x7fffffff)%(SHARED_SIZE - 1);
    res = LockFile(id->h, SHARED_FIRST+id->sharedLockByte, 0, 1, 0);
  }
  return res;
}

/*
** Undo a readlock
*/
................................................................................
    res = UnlockFile(pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
  }else{
    res = UnlockFile(pFile->h, SHARED_FIRST + pFile->sharedLockByte, 0, 1, 0);
  }
  return res;
}

#ifndef SQLITE_OMIT_PAGER_PRAGMAS
/*
** Check that a given pathname is a directory and is writable 
**
*/
int sqlite3WinIsDirWritable(char *zDirname){
  int fileAttr;
  void *zConverted;
  if( zDirname==0 ) return 0;
  if( !isNT() && strlen(zDirname)>MAX_PATH ) return 0;

  zConverted = convertUtf8Filename(zDirname);
  if( zConverted==0 ){
    return SQLITE_NOMEM;
  }
  if( isNT() ){
    fileAttr = GetFileAttributesW((WCHAR*)zConverted);
  }else{
#if OS_WINCE
    return 0;
#else
    fileAttr = GetFileAttributesA((char*)zConverted);
#endif
  }
  sqliteFree(zConverted);
  if( fileAttr == 0xffffffff ) return 0;
  if( (fileAttr & FILE_ATTRIBUTE_DIRECTORY) != FILE_ATTRIBUTE_DIRECTORY ){
    return 0;
  }
  return 1;
}
#endif /* SQLITE_OMIT_PAGER_PRAGMAS */

/*
** Lock the file with the lock specified by parameter locktype - one
** of the following:
**
**     (1) SHARED_LOCK
**     (2) RESERVED_LOCK
**     (3) PENDING_LOCK
................................................................................
**    PENDING -> EXCLUSIVE
**
** This routine will only increase a lock.  The winUnlock() routine
** erases all locks at once and returns us immediately to locking level 0.
** It is not possible to lower the locking level one step at a time.  You
** must go straight to locking level 0.
*/
static int winLock(OsFile *id, int locktype){
  int rc = SQLITE_OK;    /* Return code from subroutines */
  int res = 1;           /* Result of a windows lock call */
  int newLocktype;       /* Set id->locktype to this value before exiting */
  int gotPendingLock = 0;/* True if we acquired a PENDING lock this time */
  winFile *pFile = (winFile*)id;

  assert( pFile!=0 );
  OSTRACE5("LOCK %d %d was %d(%d)\n",
          pFile->h, locktype, pFile->locktype, pFile->sharedLockByte);

................................................................................
}

/*
** This routine checks if there is a RESERVED lock held on the specified
** file by this or any other process. If such a lock is held, return
** non-zero, otherwise zero.
*/
static int winCheckReservedLock(OsFile *id){
  int rc;
  winFile *pFile = (winFile*)id;
  assert( pFile!=0 );
  if( pFile->locktype>=RESERVED_LOCK ){
    rc = 1;
    OSTRACE3("TEST WR-LOCK %d %d (local)\n", pFile->h, rc);
  }else{
................................................................................
** If the locking level of the file descriptor is already at or below
** the requested locking level, this routine is a no-op.
**
** It is not possible for this routine to fail if the second argument
** is NO_LOCK.  If the second argument is SHARED_LOCK then this routine
** might return SQLITE_IOERR;
*/
static int winUnlock(OsFile *id, int locktype){
  int type;
  int rc = SQLITE_OK;
  winFile *pFile = (winFile*)id;

  assert( pFile!=0 );
  assert( locktype<=SHARED_LOCK );
  OSTRACE5("UNLOCK %d to %d was %d(%d)\n", pFile->h, locktype,
          pFile->locktype, pFile->sharedLockByte);
  type = pFile->locktype;
  if( type>=EXCLUSIVE_LOCK ){
    UnlockFile(pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
................................................................................
    UnlockFile(pFile->h, PENDING_BYTE, 0, 1, 0);
  }
  pFile->locktype = locktype;
  return rc;
}

/*
** Turn a relative pathname into a full pathname.  Return a pointer
** to the full pathname stored in space obtained from sqliteMalloc().
** The calling function is responsible for freeing this space once it
** is no longer needed.
*/
char *sqlite3WinFullPathname(const char *zRelative){
  char *zFull;
#if defined(__CYGWIN__)
  int nByte;
  nByte = strlen(zRelative) + MAX_PATH + 1001;
  zFull = sqliteMalloc( nByte );
  if( zFull==0 ) return 0;
  if( cygwin_conv_to_full_win32_path(zRelative, zFull) ) return 0;
#elif OS_WINCE
  /* WinCE has no concept of a relative pathname, or so I am told. */
  zFull = sqliteStrDup(zRelative);
#else
  int nByte;
  void *zConverted;
  zConverted = convertUtf8Filename(zRelative);
  if( isNT() ){
    WCHAR *zTemp;
    nByte = GetFullPathNameW((WCHAR*)zConverted, 0, 0, 0) + 3;
    zTemp = sqliteMalloc( nByte*sizeof(zTemp[0]) );
    if( zTemp==0 ){
      sqliteFree(zConverted);

      return 0;
    }
    GetFullPathNameW((WCHAR*)zConverted, nByte, zTemp, 0);
    sqliteFree(zConverted);
    zFull = unicodeToUtf8(zTemp);
    sqliteFree(zTemp);
  }else{
    char *zTemp;
    nByte = GetFullPathNameA((char*)zConverted, 0, 0, 0) + 3;
    zTemp = sqliteMalloc( nByte*sizeof(zTemp[0]) );
    if( zTemp==0 ){
      sqliteFree(zConverted);
      return 0;
    }
    GetFullPathNameA((char*)zConverted, nByte, zTemp, 0);
    sqliteFree(zConverted);
    zFull = mbcsToUtf8(zTemp);
    sqliteFree(zTemp);
  }
#endif
  return zFull;
}

/*
** The fullSync option is meaningless on windows.   This is a no-op.
*/
static void winSetFullSync(OsFile *id, int v){
  return;
}

/*
** Return the underlying file handle for an OsFile
*/
static int winFileHandle(OsFile *id){
  return (int)((winFile*)id)->h;
}

/*
** Return an integer that indices the type of lock currently held
** by this handle.  (Used for testing and analysis only.)
*/
static int winLockState(OsFile *id){

  return ((winFile*)id)->locktype;
}

/*
** Return the sector size in bytes of the underlying block device for
** the specified file. This is almost always 512 bytes, but may be
** larger for some devices.
**
** SQLite code assumes this function cannot fail. It also assumes that
** if two files are created in the same file-system directory (i.e.
** a database and it's journal file) that the sector size will be the
** same for both.
*/
static int winSectorSize(OsFile *id){
  return SQLITE_DEFAULT_SECTOR_SIZE;
}

/*







** This vector defines all the methods that can operate on an OsFile
** for win32.
*/
static const IoMethod sqlite3WinIoMethod = {


  winClose,
  winOpenDirectory,
  winRead,
  winWrite,
  winSeek,
  winTruncate,
  winSync,
  winSetFullSync,
  winFileHandle,
  winFileSize,
  winLock,
  winUnlock,
  winLockState,
  winCheckReservedLock,


  winSectorSize,

};







/*
** Allocate memory for an OsFile.  Initialize the new OsFile
** to the value given in pInit and return a pointer to the new
** OsFile.  If we run out of memory, close the file and return NULL.




*/
static int allocateWinFile(winFile *pInit, OsFile **pId){


























  winFile *pNew;
  pNew = sqliteMalloc( sizeof(*pNew) );
  if( pNew==0 ){
    CloseHandle(pInit->h);











































#if OS_WINCE









































    sqliteFree(pInit->zDeleteOnClose);

#endif
























    *pId = 0;



    return SQLITE_NOMEM;







  }else{
    *pNew = *pInit;
    pNew->pMethod = &sqlite3WinIoMethod;
    pNew->locktype = NO_LOCK;
    pNew->sharedLockByte = 0;
    *pId = (OsFile*)pNew;
    OpenCounter(+1);







































































































    return SQLITE_OK;
  }
}





















































#endif /* SQLITE_OMIT_DISKIO */
/***************************************************************************
** Everything above deals with file I/O.  Everything that follows deals
** with other miscellanous aspects of the operating system interface
****************************************************************************/






#if !defined(SQLITE_OMIT_LOAD_EXTENSION)
/*
** Interfaces for opening a shared library, finding entry points
** within the shared library, and closing the shared library.
*/
void *sqlite3WinDlopen(const char *zFilename){





  HANDLE h;
  void *zConverted = convertUtf8Filename(zFilename);
  if( zConverted==0 ){
    return 0;
  }
  if( isNT() ){
    h = LoadLibraryW((WCHAR*)zConverted);
................................................................................
  }else{
#if OS_WINCE
    return 0;
#else
    h = LoadLibraryA((char*)zConverted);
#endif
  }
  sqliteFree(zConverted);
  return (void*)h;
  










}
void *sqlite3WinDlsym(void *pHandle, const char *zSymbol){
#if OS_WINCE
  /* The GetProcAddressA() routine is only available on wince. */
  return GetProcAddressA((HANDLE)pHandle, zSymbol);
#else
  /* All other windows platforms expect GetProcAddress() to take
  ** an Ansi string regardless of the _UNICODE setting */
  return GetProcAddress((HANDLE)pHandle, zSymbol);
#endif
}
int sqlite3WinDlclose(void *pHandle){
  return FreeLibrary((HANDLE)pHandle);
}
#endif /* !SQLITE_OMIT_LOAD_EXTENSION */







/*
** Get information to seed the random number generator.  The seed
** is written into the buffer zBuf[256].  The calling function must
** supply a sufficiently large buffer.

*/
int sqlite3WinRandomSeed(char *zBuf){
  /* We have to initialize zBuf to prevent valgrind from reporting
  ** errors.  The reports issued by valgrind are incorrect - we would
  ** prefer that the randomness be increased by making use of the
  ** uninitialized space in zBuf - but valgrind errors tend to worry
  ** some users.  Rather than argue, it seems easier just to initialize
  ** the whole array and silence valgrind, even if that means less randomness
  ** in the random seed.
  **
  ** When testing, initializing zBuf[] to zero is all we do.  That means
  ** that we always use the same random number sequence.* This makes the
  ** tests repeatable.
  */
  memset(zBuf, 0, 256);
  GetSystemTime((LPSYSTEMTIME)zBuf);


  return SQLITE_OK;
}



/*
** Sleep for a little while.  Return the amount of time slept.
*/
int sqlite3WinSleep(int ms){
  Sleep(ms);
  return ms;
}

/*
** Static variables used for thread synchronization
*/
static int inMutex = 0;
#ifdef SQLITE_W32_THREADS
  static DWORD mutexOwner;
  static CRITICAL_SECTION cs;
#endif

/*
** The following pair of routines implement mutual exclusion for
** multi-threaded processes.  Only a single thread is allowed to
** executed code that is surrounded by EnterMutex() and LeaveMutex().
**
** SQLite uses only a single Mutex.  There is not much critical
** code and what little there is executes quickly and without blocking.
**
** Version 3.3.1 and earlier used a simple mutex.  Beginning with
** version 3.3.2, a recursive mutex is required.
*/
void sqlite3WinEnterMutex(){
#ifdef SQLITE_W32_THREADS
  static int isInit = 0;
  while( !isInit ){
    static long lock = 0;
    if( InterlockedIncrement(&lock)==1 ){
      InitializeCriticalSection(&cs);
      isInit = 1;
    }else{
      Sleep(1);
    }
  }
  EnterCriticalSection(&cs);
  mutexOwner = GetCurrentThreadId();
#endif
  inMutex++;
}
void sqlite3WinLeaveMutex(){
  assert( inMutex );
  inMutex--;
#ifdef SQLITE_W32_THREADS
  assert( mutexOwner==GetCurrentThreadId() );
  LeaveCriticalSection(&cs);
#endif
}

/*
** Return TRUE if the mutex is currently held.
**
** If the thisThreadOnly parameter is true, return true if and only if the
** calling thread holds the mutex.  If the parameter is false, return
** true if any thread holds the mutex.
*/
int sqlite3WinInMutex(int thisThreadOnly){
#ifdef SQLITE_W32_THREADS
  return inMutex>0 && (thisThreadOnly==0 || mutexOwner==GetCurrentThreadId());
#else
  return inMutex>0;
#endif
}


/*
** The following variable, if set to a non-zero value, becomes the result
** returned from sqlite3OsCurrentTime().  This is used for testing.
*/
#ifdef SQLITE_TEST
int sqlite3_current_time = 0;
................................................................................
#endif

/*
** Find the current time (in Universal Coordinated Time).  Write the
** current time and date as a Julian Day number into *prNow and
** return 0.  Return 1 if the time and date cannot be found.
*/
int sqlite3WinCurrentTime(double *prNow){
  FILETIME ft;
  /* FILETIME structure is a 64-bit value representing the number of 
     100-nanosecond intervals since January 1, 1601 (= JD 2305813.5). 
  */
  double now;
#if OS_WINCE
  SYSTEMTIME time;
................................................................................
#ifdef SQLITE_TEST
  if( sqlite3_current_time ){
    *prNow = sqlite3_current_time/86400.0 + 2440587.5;
  }
#endif
  return 0;
}


/*
** Remember the number of thread-specific-data blocks allocated.
** Use this to verify that we are not leaking thread-specific-data.
** Ticket #1601


*/
#ifdef SQLITE_TEST
int sqlite3_tsd_count = 0;
# define TSD_COUNTER_INCR InterlockedIncrement(&sqlite3_tsd_count)
# define TSD_COUNTER_DECR InterlockedDecrement(&sqlite3_tsd_count)
#else
# define TSD_COUNTER_INCR  /* no-op */
# define TSD_COUNTER_DECR  /* no-op */
#endif







/*
** If called with allocateFlag>1, then return a pointer to thread
** specific data for the current thread.  Allocate and zero the
** thread-specific data if it does not already exist necessary.
**
** If called with allocateFlag==0, then check the current thread
** specific data.  Return it if it exists.  If it does not exist,
** then return NULL.
**
** If called with allocateFlag<0, check to see if the thread specific
** data is allocated and is all zero.  If it is then deallocate it.
** Return a pointer to the thread specific data or NULL if it is
** unallocated or gets deallocated.
*/
ThreadData *sqlite3WinThreadSpecificData(int allocateFlag){
  static int key;
  static int keyInit = 0;
  static const ThreadData zeroData = {0};
  ThreadData *pTsd;

  if( !keyInit ){
    sqlite3OsEnterMutex();
    if( !keyInit ){
      key = TlsAlloc();
      if( key==0xffffffff ){
        sqlite3OsLeaveMutex();
        return 0;
      }
      keyInit = 1;
    }
    sqlite3OsLeaveMutex();

  }
  pTsd = TlsGetValue(key);
  if( allocateFlag>0 ){
    if( !pTsd ){
      pTsd = sqlite3OsMalloc( sizeof(zeroData) );
      if( pTsd ){
        *pTsd = zeroData;
        TlsSetValue(key, pTsd);
        TSD_COUNTER_INCR;
      }
    }
  }else if( pTsd!=0 && allocateFlag<0 
              && memcmp(pTsd, &zeroData, sizeof(ThreadData))==0 ){
    sqlite3OsFree(pTsd);
    TlsSetValue(key, 0);
    TSD_COUNTER_DECR;
    pTsd = 0;
  }
  return pTsd;
}
#endif /* OS_WIN */

  BOOL bPending;      /* Indicates a pending lock has been obtained */
  BOOL bReserved;     /* Indicates a reserved lock has been obtained */
  BOOL bExclusive;    /* Indicates an exclusive lock has been obtained */
} winceLock;
#endif

/*
** The winFile structure is a subclass of sqlite3_file* specific to the win32
** portability layer.
*/
typedef struct winFile winFile;
struct winFile {
  const sqlite3_io_methods *pMethod;/* Must be first */
  HANDLE h;               /* Handle for accessing the file */
  unsigned char locktype; /* Type of lock currently held on this file */
  short sharedLockByte;   /* Randomly chosen byte used as a shared lock */
#if OS_WINCE
  WCHAR *zDeleteOnClose;  /* Name of file to delete when closing */
  HANDLE hMutex;          /* Mutex used to control access to shared lock */  
  HANDLE hShared;         /* Shared memory segment used for locking */
  winceLock local;        /* Locks obtained by this instance of winFile */
  winceLock *shared;      /* Global shared lock memory for the file  */
#endif
};









/*
** The following variable is (normally) set once and never changes
** thereafter.  It records whether the operating system is Win95
** or WinNT.
**
** 0:   Operating system unknown.
** 1:   Operating system is Win95.
** 2:   Operating system is WinNT.
**
** In order to facilitate testing on a WinNT system, the test fixture
** can manually set this value to 1 to emulate Win98 behavior.
*/
#ifdef SQLITE_TEST
int sqlite3_os_type = 0;
#else
static int sqlite3_os_type = 0;
#endif

/*
** Return true (non-zero) if we are running under WinNT, Win2K, WinXP,
** or WinCE.  Return false (zero) for Win95, Win98, or WinME.
**
** Here is an interesting observation:  Win95, Win98, and WinME lack
** the LockFileEx() API.  But we can still statically link against that
................................................................................
    return sqlite3_os_type==2;
  }
#endif /* OS_WINCE */

/*
** Convert a UTF-8 string to microsoft unicode (UTF-16?). 
**
** Space to hold the returned string is obtained from sqlite3_malloc.
*/
static WCHAR *utf8ToUnicode(const char *zFilename){
  int nChar;
  WCHAR *zWideFilename;

  nChar = MultiByteToWideChar(CP_UTF8, 0, zFilename, -1, NULL, 0);
  zWideFilename = sqlite3_malloc( nChar*sizeof(zWideFilename[0]) );
  if( zWideFilename==0 ){
    return 0;
  }
  nChar = MultiByteToWideChar(CP_UTF8, 0, zFilename, -1, zWideFilename, nChar);
  if( nChar==0 ){
    sqlite3_free(zWideFilename);
    zWideFilename = 0;
  }
  return zWideFilename;
}

/*
** Convert microsoft unicode to UTF-8.  Space to hold the returned string is
** obtained from sqlite3_malloc().
*/
static char *unicodeToUtf8(const WCHAR *zWideFilename){
  int nByte;
  char *zFilename;

  nByte = WideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, 0, 0, 0, 0);
  zFilename = sqlite3_malloc( nByte );
  if( zFilename==0 ){
    return 0;
  }
  nByte = WideCharToMultiByte(CP_UTF8, 0, zWideFilename, -1, zFilename, nByte,
                              0, 0);
  if( nByte == 0 ){
    sqlite3_free(zFilename);
    zFilename = 0;
  }
  return zFilename;
}

/*
** Convert an ansi string to microsoft unicode, based on the
** current codepage settings for file apis.
** 
** Space to hold the returned string is obtained
** from sqlite3_malloc.
*/
static WCHAR *mbcsToUnicode(const char *zFilename){
  int nByte;
  WCHAR *zMbcsFilename;
  int codepage = AreFileApisANSI() ? CP_ACP : CP_OEMCP;

  nByte = MultiByteToWideChar(codepage, 0, zFilename, -1, NULL,0)*sizeof(WCHAR);
  zMbcsFilename = sqlite3_malloc( nByte*sizeof(zMbcsFilename[0]) );
  if( zMbcsFilename==0 ){
    return 0;
  }
  nByte = MultiByteToWideChar(codepage, 0, zFilename, -1, zMbcsFilename, nByte);
  if( nByte==0 ){
    sqlite3_free(zMbcsFilename);
    zMbcsFilename = 0;
  }
  return zMbcsFilename;
}

/*
** Convert microsoft unicode to multibyte character string, based on the
** user's Ansi codepage.
**
** Space to hold the returned string is obtained from
** sqlite3_malloc().
*/
static char *unicodeToMbcs(const WCHAR *zWideFilename){
  int nByte;
  char *zFilename;
  int codepage = AreFileApisANSI() ? CP_ACP : CP_OEMCP;

  nByte = WideCharToMultiByte(codepage, 0, zWideFilename, -1, 0, 0, 0, 0);
  zFilename = sqlite3_malloc( nByte );
  if( zFilename==0 ){
    return 0;
  }
  nByte = WideCharToMultiByte(codepage, 0, zWideFilename, -1, zFilename, nByte,
                              0, 0);
  if( nByte == 0 ){
    sqlite3_free(zFilename);
    zFilename = 0;
  }
  return zFilename;
}

/*
** Convert multibyte character string to UTF-8.  Space to hold the
** returned string is obtained from sqlite3_malloc().
*/
static char *mbcsToUtf8(const char *zFilename){
  char *zFilenameUtf8;
  WCHAR *zTmpWide;

  zTmpWide = mbcsToUnicode(zFilename);
  if( zTmpWide==0 ){
    return 0;
  }
  zFilenameUtf8 = unicodeToUtf8(zTmpWide);
  sqlite3_free(zTmpWide);
  return zFilenameUtf8;
}

/*
** Convert UTF-8 to multibyte character string.  Space to hold the 
** returned string is obtained from sqlite3_malloc().
*/
static char *utf8ToMbcs(const char *zFilename){
  char *zFilenameMbcs;
  WCHAR *zTmpWide;

  zTmpWide = utf8ToUnicode(zFilename);
  if( zTmpWide==0 ){
    return 0;
  }
  zFilenameMbcs = unicodeToMbcs(zTmpWide);
  sqlite3_free(zTmpWide);
  return zFilenameMbcs;
}

#if OS_WINCE
/*************************************************************************
** This section contains code for WinCE only.
*/
................................................................................
  for (;*zTok;zTok++){
    if (*zTok == '\\') *zTok = '_';
  }

  /* Create/open the named mutex */
  pFile->hMutex = CreateMutexW(NULL, FALSE, zName);
  if (!pFile->hMutex){
    sqlite3_free(zName);
    return FALSE;
  }

  /* Acquire the mutex before continuing */
  winceMutexAcquire(pFile->hMutex);
  
  /* Since the names of named mutexes, semaphores, file mappings etc are 
................................................................................

  /* Set a flag that indicates we're the first to create the memory so it 
  ** must be zero-initialized */
  if (GetLastError() == ERROR_ALREADY_EXISTS){
    bInit = FALSE;
  }

  sqlite3_free(zName);

  /* If we succeeded in making the shared memory handle, map it. */
  if (pFile->hShared){
    pFile->shared = (winceLock*)MapViewOfFile(pFile->hShared, 
             FILE_MAP_READ|FILE_MAP_WRITE, 0, 0, sizeof(winceLock));
    /* If mapping failed, close the shared memory handle and erase it */
    if (!pFile->shared){
................................................................................

    /* De-reference and close our copy of the shared memory handle */
    UnmapViewOfFile(pFile->shared);
    CloseHandle(pFile->hShared);

    if( pFile->zDeleteOnClose ){
      DeleteFileW(pFile->zDeleteOnClose);
      sqlite3_free(pFile->zDeleteOnClose);
      pFile->zDeleteOnClose = 0;
    }

    /* Done with the mutex */
    winceMutexRelease(pFile->hMutex);    
    CloseHandle(pFile->hMutex);
    pFile->hMutex = NULL;
................................................................................
  return FALSE;
}
/*
** End of the special code for wince
*****************************************************************************/
#endif /* OS_WINCE */

/*****************************************************************************
** The next group of routines implement the I/O methods specified
** by the sqlite3_io_methods object.
******************************************************************************/













/*


























































































































































































































































































































































































** Close a file.
**
** It is reported that an attempt to close a handle might sometimes
** fail.  This is a very unreasonable result, but windows is notorious
** for being unreasonable so I do not doubt that it might happen.  If
** the close fails, we pause for 100 milliseconds and try again.  As
** many as MX_CLOSE_ATTEMPT attempts to close the handle are made before
** giving up and returning an error.
*/
#define MX_CLOSE_ATTEMPT 3
static int winClose(sqlite3_file *id){



  int rc, cnt = 0;
  winFile *pFile = (winFile*)id;
  OSTRACE2("CLOSE %d\n", pFile->h);
  do{
    rc = CloseHandle(pFile->h);
  }while( rc==0 && cnt++ < MX_CLOSE_ATTEMPT && (Sleep(100), 1) );
#if OS_WINCE
  winceDestroyLock(pFile);
#endif
  OpenCounter(-1);



  return rc ? SQLITE_OK : SQLITE_IOERR;
}

/*
** Some microsoft compilers lack this definition.
*/
#ifndef INVALID_SET_FILE_POINTER
# define INVALID_SET_FILE_POINTER ((DWORD)-1)
#endif

/*
** Read data from a file into a buffer.  Return SQLITE_OK if all
** bytes were read successfully and SQLITE_IOERR if anything goes
** wrong.
*/
static int winRead(
  sqlite3_file *id,          /* File to read from */
  void *pBuf,                /* Write content into this buffer */
  int amt,                   /* Number of bytes to read */
  sqlite3_int64 offset       /* Begin reading at this offset */
){
  LONG upperBits = (offset>>32) & 0x7fffffff;
  LONG lowerBits = offset & 0xffffffff;
  DWORD rc;
  DWORD got;
  winFile *pFile = (winFile*)id;
  assert( id!=0 );
  SimulateIOError(return SQLITE_IOERR_READ);
  OSTRACE3("READ %d lock=%d\n", pFile->h, pFile->locktype);
  rc = SetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
  if( rc==INVALID_SET_FILE_POINTER && GetLastError()!=NO_ERROR ){
    return SQLITE_FULL;
  }
  if( !ReadFile(pFile->h, pBuf, amt, &got, 0) ){
    return SQLITE_IOERR_READ;
  }
  if( got==(DWORD)amt ){
    return SQLITE_OK;
  }else{
    memset(&((char*)pBuf)[got], 0, amt-got);
    return SQLITE_IOERR_SHORT_READ;
................................................................................
  }
}

/*
** Write data from a buffer into a file.  Return SQLITE_OK on success
** or some other error code on failure.
*/
static int winWrite(
  sqlite3_file *id,         /* File to write into */
  const void *pBuf,         /* The bytes to be written */
  int amt,                  /* Number of bytes to write */
  sqlite3_int64 offset      /* Offset into the file to begin writing at */
){
  LONG upperBits = (offset>>32) & 0x7fffffff;
  LONG lowerBits = offset & 0xffffffff;
  DWORD rc;
  DWORD wrote;
  winFile *pFile = (winFile*)id;
  assert( id!=0 );
  SimulateIOError(return SQLITE_IOERR_WRITE);
  SimulateDiskfullError(return SQLITE_FULL);
  OSTRACE3("WRITE %d lock=%d\n", pFile->h, pFile->locktype);
  rc = SetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);
  if( rc==INVALID_SET_FILE_POINTER && GetLastError()!=NO_ERROR ){
    return SQLITE_FULL;
  }
  assert( amt>0 );
  while(
     amt>0
     && (rc = WriteFile(pFile->h, pBuf, amt, &wrote, 0))!=0
     && wrote>0
  ){
    amt -= wrote;
    pBuf = &((char*)pBuf)[wrote];
  }
  if( !rc || amt>(int)wrote ){
    return SQLITE_FULL;
  }
  return SQLITE_OK;
}

/*
** Truncate an open file to a specified size
*/
static int winTruncate(sqlite3_file *id, i64 nByte){







  LONG upperBits = (nByte>>32) & 0x7fffffff;
  LONG lowerBits = nByte & 0xffffffff;



  winFile *pFile = (winFile*)id;
  OSTRACE3("TRUNCATE %d %lld\n", pFile->h, nByte);
  SimulateIOError(return SQLITE_IOERR_TRUNCATE);

  SetFilePointer(pFile->h, lowerBits, &upperBits, FILE_BEGIN);




  SetEndOfFile(pFile->h);
  return SQLITE_OK;
}

/*
** Make sure all writes to a particular file are committed to disk.
*/
static int winSync(sqlite3_file *id, int flags){
  winFile *pFile = (winFile*)id;
  OSTRACE3("SYNC %d lock=%d\n", pFile->h, pFile->locktype);
  if( FlushFileBuffers(pFile->h) ){
    return SQLITE_OK;
  }else{
    return SQLITE_IOERR;
  }
}

/*






















** Determine the current size of a file in bytes
*/
static int winFileSize(sqlite3_file *id, sqlite3_int64 *pSize){
  winFile *pFile = (winFile*)id;
  DWORD upperBits, lowerBits;

  SimulateIOError(return SQLITE_IOERR_FSTAT);
  lowerBits = GetFileSize(pFile->h, &upperBits);
  *pSize = (((sqlite3_int64)upperBits)<<32) + lowerBits;
  return SQLITE_OK;
}

/*
** LOCKFILE_FAIL_IMMEDIATELY is undefined on some Windows systems.
*/
#ifndef LOCKFILE_FAIL_IMMEDIATELY
................................................................................
#endif

/*
** Acquire a reader lock.
** Different API routines are called depending on whether or not this
** is Win95 or WinNT.
*/
static int getReadLock(winFile *pFile){
  int res;
  if( isNT() ){
    OVERLAPPED ovlp;
    ovlp.Offset = SHARED_FIRST;
    ovlp.OffsetHigh = 0;
    ovlp.hEvent = 0;
    res = LockFileEx(pFile->h, LOCKFILE_FAIL_IMMEDIATELY,
                     0, SHARED_SIZE, 0, &ovlp);
  }else{
    int lk;
    sqlite3Randomness(sizeof(lk), &lk);
    pFile->sharedLockByte = (lk & 0x7fffffff)%(SHARED_SIZE - 1);
    res = LockFile(pFile->h, SHARED_FIRST+pFile->sharedLockByte, 0, 1, 0);
  }
  return res;
}

/*
** Undo a readlock
*/
................................................................................
    res = UnlockFile(pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
  }else{
    res = UnlockFile(pFile->h, SHARED_FIRST + pFile->sharedLockByte, 0, 1, 0);
  }
  return res;
}


































/*
** Lock the file with the lock specified by parameter locktype - one
** of the following:
**
**     (1) SHARED_LOCK
**     (2) RESERVED_LOCK
**     (3) PENDING_LOCK
................................................................................
**    PENDING -> EXCLUSIVE
**
** This routine will only increase a lock.  The winUnlock() routine
** erases all locks at once and returns us immediately to locking level 0.
** It is not possible to lower the locking level one step at a time.  You
** must go straight to locking level 0.
*/
static int winLock(sqlite3_file *id, int locktype){
  int rc = SQLITE_OK;    /* Return code from subroutines */
  int res = 1;           /* Result of a windows lock call */
  int newLocktype;       /* Set pFile->locktype to this value before exiting */
  int gotPendingLock = 0;/* True if we acquired a PENDING lock this time */
  winFile *pFile = (winFile*)id;

  assert( pFile!=0 );
  OSTRACE5("LOCK %d %d was %d(%d)\n",
          pFile->h, locktype, pFile->locktype, pFile->sharedLockByte);

................................................................................
}

/*
** This routine checks if there is a RESERVED lock held on the specified
** file by this or any other process. If such a lock is held, return
** non-zero, otherwise zero.
*/
static int winCheckReservedLock(sqlite3_file *id){
  int rc;
  winFile *pFile = (winFile*)id;
  assert( pFile!=0 );
  if( pFile->locktype>=RESERVED_LOCK ){
    rc = 1;
    OSTRACE3("TEST WR-LOCK %d %d (local)\n", pFile->h, rc);
  }else{
................................................................................
** If the locking level of the file descriptor is already at or below
** the requested locking level, this routine is a no-op.
**
** It is not possible for this routine to fail if the second argument
** is NO_LOCK.  If the second argument is SHARED_LOCK then this routine
** might return SQLITE_IOERR;
*/
static int winUnlock(sqlite3_file *id, int locktype){
  int type;

  winFile *pFile = (winFile*)id;
  int rc = SQLITE_OK;
  assert( pFile!=0 );
  assert( locktype<=SHARED_LOCK );
  OSTRACE5("UNLOCK %d to %d was %d(%d)\n", pFile->h, locktype,
          pFile->locktype, pFile->sharedLockByte);
  type = pFile->locktype;
  if( type>=EXCLUSIVE_LOCK ){
    UnlockFile(pFile->h, SHARED_FIRST, 0, SHARED_SIZE, 0);
................................................................................
    UnlockFile(pFile->h, PENDING_BYTE, 0, 1, 0);
  }
  pFile->locktype = locktype;
  return rc;
}

/*
** Currently unimplemented



*/





















static int winBreakLock(sqlite3_file *id){
  return SQLITE_ERROR;
}





















/*














** Return an integer that indices the type of lock currently held
** by this handle.  (Used for testing and analysis only.)
*/
static int winLockState(sqlite3_file *id){
  winFile *pFile = (winFile*)id;
  return pFile->locktype;
}

/*
** Return the sector size in bytes of the underlying block device for
** the specified file. This is almost always 512 bytes, but may be
** larger for some devices.
**
** SQLite code assumes this function cannot fail. It also assumes that
** if two files are created in the same file-system directory (i.e.
** a database and it's journal file) that the sector size will be the
** same for both.
*/
static int winSectorSize(sqlite3_file *id){
  return SQLITE_DEFAULT_SECTOR_SIZE;
}

/*
** Return a vector of device characteristics.
*/
static int winDeviceCharacteristics(sqlite3_file *id){
  return 0;
}

/*
** This vector defines all the methods that can operate on an
** sqlite3_file for win32.
*/

static const sqlite3_io_methods winIoMethod = {
  1,                        /* iVersion */
  winClose,

  winRead,
  winWrite,

  winTruncate,
  winSync,


  winFileSize,
  winLock,
  winUnlock,

  winCheckReservedLock,
  winBreakLock,
  winLockState,
  winSectorSize,
  winDeviceCharacteristics
};

/***************************************************************************
** Here ends the I/O methods that form the sqlite3_io_methods object.
**
** The next block of code implements the VFS methods.
****************************************************************************/

/*



** Convert a UTF-8 filename into whatever form the underlying
** operating system wants filenames in.  Space to hold the result
** is obtained from sqlite3_malloc and must be freed by the calling
** function.
*/

static void *convertUtf8Filename(const char *zFilename){
  void *zConverted = 0;
  if( isNT() ){
    zConverted = utf8ToUnicode(zFilename);
  }else{
    zConverted = utf8ToMbcs(zFilename);
  }
  /* caller will handle out of memory */
  return zConverted;
}

/*
** Open a file.
*/
static int winOpen(
  sqlite3_vfs *pVfs,        /* Not used */
  const char *zName,        /* Name of the file (UTF-8) */
  sqlite3_file *id,         /* Write the SQLite file handle here */
  int flags,                /* Open mode flags */
  int *pOutFlags            /* Status return flags */
){
  HANDLE h;
  DWORD dwDesiredAccess;
  DWORD dwShareMode;
  DWORD dwCreationDisposition;
  DWORD dwFlagsAndAttributes = 0;
  winFile *pFile = (winFile*)id;



  void *zConverted = convertUtf8Filename(zName);
  if( zConverted==0 ){
    return SQLITE_NOMEM;
  }

  if( flags & SQLITE_OPEN_READWRITE ){
    dwDesiredAccess = GENERIC_READ | GENERIC_WRITE;
  }else{
    dwDesiredAccess = GENERIC_READ;
  }
  if( flags & SQLITE_OPEN_CREATE ){
    dwCreationDisposition = OPEN_ALWAYS;
  }else{
    dwCreationDisposition = OPEN_EXISTING;
  }
  if( flags & SQLITE_OPEN_MAIN_DB ){
    dwShareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
  }else{
    dwShareMode = 0;
  }
  if( flags & (SQLITE_OPEN_TEMP_DB | SQLITE_OPEN_TEMP_JOURNAL
                    | SQLITE_OPEN_SUBJOURNAL) ){
    dwFlagsAndAttributes = FILE_ATTRIBUTE_TEMPORARY
                               | FILE_ATTRIBUTE_HIDDEN
                               | FILE_FLAG_DELETE_ON_CLOSE;
  }else{
    dwFlagsAndAttributes = FILE_ATTRIBUTE_NORMAL;
  }
  if( flags & (SQLITE_OPEN_MAIN_DB | SQLITE_OPEN_TEMP_DB) ){
    dwFlagsAndAttributes |= FILE_FLAG_RANDOM_ACCESS;
  }else{
    dwFlagsAndAttributes |= FILE_FLAG_SEQUENTIAL_SCAN;
  }
  if( isNT() ){
    h = CreateFileW((WCHAR*)zConverted,
       dwDesiredAccess,
       dwShareMode,
       NULL,
       dwCreationDisposition,
       dwFlagsAndAttributes,
       NULL
    );
  }else{
#if OS_WINCE
    return SQLITE_NOMEM;
#else
    h = CreateFileA((char*)zConverted,
       dwDesiredAccess,
       dwShareMode,
       NULL,
       dwCreationDisposition,
       dwFlagsAndAttributes,
       NULL
    );
#endif
  }
  if( h==INVALID_HANDLE_VALUE ){
    if( flags & SQLITE_OPEN_READWRITE ){
      sqlite3_free(zConverted);
      return winOpen(0, zName, id, 
             ((flags|SQLITE_OPEN_READONLY)&~SQLITE_OPEN_READWRITE), pOutFlags);
    }else{
      return SQLITE_CANTOPEN;
    }
  }
  if( pOutFlags ){
    if( flags & SQLITE_OPEN_READWRITE ){
      *pOutFlags = SQLITE_OPEN_READWRITE;
    }else{
      *pOutFlags = SQLITE_OPEN_READONLY;
    }
  }
  memset(pFile, 0, sizeof(*pFile));
  pFile->pMethod = &winIoMethod;
  pFile->h = h;
#if OS_WINCE
  if( (flags & (SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_DB)) ==
               (SQLITE_OPEN_READWRITE|SQLITE_OPEN_MAIN_DB)
       && !winceCreateLock(zFilename, &f)
  ){
    CloseHandle(h);
    sqlite3_free(zConverted);
    return SQLITE_CANTOPEN;
  }
  if( dwFlagsAndAttributes & FILE_FLAG_DELETEONCLOSE ){
    pFile->zDeleteOnClose = zConverted;
  }else
#endif
  {
    sqlite3_free(zConverted);
  }
  return SQLITE_OK;
}

/*
** Delete the named file.
**
** Note that windows does not allow a file to be deleted if some other
** process has it open.  Sometimes a virus scanner or indexing program
** will open a journal file shortly after it is created in order to do
** whatever it is it does.  While this other process is holding the
** file open, we will be unable to delete it.  To work around this
** problem, we delay 100 milliseconds and try to delete again.  Up
** to MX_DELETION_ATTEMPTs deletion attempts are run before giving
** up and returning an error.
*/
#define MX_DELETION_ATTEMPTS 3
static int winDelete(
  sqlite3_vfs *pVfs,          /* Not used on win32 */
  const char *zFilename,      /* Name of file to delete */
  int syncDir                 /* Not used on win32 */
){
  int cnt = 0;
  int rc;
  void *zConverted = convertUtf8Filename(zFilename);
  if( zConverted==0 ){
    return SQLITE_NOMEM;
  }
  SimulateIOError(return SQLITE_IOERR_DELETE);
  if( isNT() ){
    do{
      rc = DeleteFileW(zConverted);
    }while( rc==0 && GetFileAttributesW(zConverted)!=0xffffffff 
            && cnt++ < MX_DELETION_ATTEMPTS && (Sleep(100), 1) );
  }else{






#if OS_WINCE
    return SQLITE_NOMEM;
#else
    do{
      rc = DeleteFileA(zConverted);
    }while( rc==0 && GetFileAttributesA(zConverted)!=0xffffffff
            && cnt++ < MX_DELETION_ATTEMPTS && (Sleep(100), 1) );
#endif
  }
  sqlite3_free(zConverted);
  OSTRACE2("DELETE \"%s\"\n", zFilename);
  return rc!=0 ? SQLITE_OK : SQLITE_IOERR;
}

/*
** Check the existance and status of a file.
*/
static int winAccess(
  sqlite3_vfs *pVfs,         /* Not used on win32 */
  const char *zFilename,     /* Name of file to check */
  int flags                  /* Type of test to make on this file */
){
  DWORD attr;
  int rc;
  void *zConverted = convertUtf8Filename(zFilename);
  if( zConverted==0 ){
    return SQLITE_NOMEM;
  }
  if( isNT() ){
    attr = GetFileAttributesW((WCHAR*)zConverted);
  }else{
#if OS_WINCE
    return SQLITE_NOMEM;
#else
    attr = GetFileAttributesA((char*)zConverted);
#endif
  }
  sqlite3_free(zConverted);
  switch( flags ){
    case SQLITE_ACCESS_EXISTS:
      rc = attr!=0xffffffff;
      break;
    case SQLITE_ACCESS_READWRITE:
      rc = (attr & FILE_ATTRIBUTE_READONLY)==0;
      break;
    case SQLITE_ACCESS_READONLY:
      rc = (attr!=0xffffffff) && ((attr & FILE_ATTRIBUTE_READONLY)==1);
      break;
    default:
      assert(!"Invalid flags argument");
  }
  return rc;
}


/*
** Create a temporary file name in zBuf.  zBuf must be big enough to
** hold at pVfs->mxPathname characters.
*/
static int winGetTempName(sqlite3_vfs *pVfs, char *zBuf){
  static char zChars[] =
    "abcdefghijklmnopqrstuvwxyz"
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    "0123456789";
  int i, j;
  char zTempPath[MAX_PATH+1];
  if( sqlite3_temp_directory ){
    sqlite3_snprintf(MAX_PATH-30, zTempPath, "%s", sqlite3_temp_directory);
  }else if( isNT() ){
    char *zMulti;
    WCHAR zWidePath[MAX_PATH];
    GetTempPathW(MAX_PATH-30, zWidePath);
    zMulti = unicodeToUtf8(zWidePath);
    if( zMulti ){
      sqlite3_snprintf(MAX_PATH-30, zTempPath, "%z", zMulti);
    }else{
      return SQLITE_NOMEM;
    }
  }else{
    char *zUtf8;
    char zMbcsPath[MAX_PATH];
    GetTempPathA(MAX_PATH-30, zMbcsPath);
    zUtf8 = mbcsToUtf8(zMbcsPath);
    if( zUtf8 ){
      sqlite3_snprintf(MAX_PATH-30, zTempPath, "%z", zUtf8);
    }else{
      return SQLITE_NOMEM;
    }
  }
  for(i=strlen(zTempPath); i>0 && zTempPath[i-1]=='\\'; i--){}
  zTempPath[i] = 0;
  for(;;){
    sqlite3_snprintf(pVfs->mxPathname-30, zBuf,
                     "%s\\"SQLITE_TEMP_FILE_PREFIX, zTempPath);
    j = strlen(zBuf);
    sqlite3Randomness(15, &zBuf[j]);
    for(i=0; i<15; i++, j++){
      zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
    }
    zBuf[j] = 0;
    if( !sqlite3OsAccess(pVfs, zBuf, SQLITE_ACCESS_EXISTS) ) break;
  }
  OSTRACE2("TEMP FILENAME: %s\n", zBuf);
  return SQLITE_OK; 
}

/*
** Turn a relative pathname into a full pathname.  Write the full
** pathname into zOut[].  zOut[] will be at least pVfs->mxPathname
** bytes in size.
*/
static int winFullPathname(
  sqlite3_vfs *pVfs,          
  const char *zRelative,
  char *zFull
){

#if defined(__CYGWIN__)
  cygwin_conv_to_full_win32_path(zRelative, zFull);
  return SQLITE_OK
#endif

#if OS_WINCE
  /* WinCE has no concept of a relative pathname, or so I am told. */
  sqlite3_snprintf(pVfs->mxPathname, zFull, "%s", zRelative);
#endif

#if !OS_WINCE && !defined(__CYGWIN__)
  int nByte;
  void *zConverted;
  char *zOut;
  zConverted = convertUtf8Filename(zRelative);
  if( isNT() ){
    WCHAR *zTemp;
    nByte = GetFullPathNameW((WCHAR*)zConverted, 0, 0, 0) + 3;
    zTemp = sqlite3_malloc( nByte*sizeof(zTemp[0]) );
    if( zTemp==0 ){
      sqlite3_free(zConverted);
      return SQLITE_NOMEM;
    }
    GetFullPathNameW((WCHAR*)zConverted, nByte, zTemp, 0);
    sqlite3_free(zConverted);
    zOut = unicodeToUtf8(zTemp);
    sqlite3_free(zTemp);
  }else{
    char *zTemp;
    nByte = GetFullPathNameA((char*)zConverted, 0, 0, 0) + 3;
    zTemp = sqlite3_malloc( nByte*sizeof(zTemp[0]) );
    if( zTemp==0 ){
      sqlite3_free(zConverted);
      return SQLITE_NOMEM;
    }
    GetFullPathNameA((char*)zConverted, nByte, zTemp, 0);
    sqlite3_free(zConverted);
    zOut = mbcsToUtf8(zTemp);
    sqlite3_free(zTemp);
  }
  if( zOut ){
    sqlite3_snprintf(pVfs->mxPathname, zFull, "%z", zOut);
    return SQLITE_OK;




  }else{
    return SQLITE_NOMEM;
  }
#endif
}

#ifndef SQLITE_OMIT_LOAD_EXTENSION
/*
** Interfaces for opening a shared library, finding entry points
** within the shared library, and closing the shared library.
*/

/*
** Interfaces for opening a shared library, finding entry points
** within the shared library, and closing the shared library.
*/
static void *winDlOpen(sqlite3_vfs *pVfs, const char *zFilename){
  HANDLE h;
  void *zConverted = convertUtf8Filename(zFilename);
  if( zConverted==0 ){
    return 0;
  }
  if( isNT() ){
    h = LoadLibraryW((WCHAR*)zConverted);
................................................................................
  }else{
#if OS_WINCE
    return 0;
#else
    h = LoadLibraryA((char*)zConverted);
#endif
  }
  sqlite3_free(zConverted);
  return (void*)h;
}
static void winDlError(sqlite3_vfs *pVfs, int nBuf, char *zBufOut){
  FormatMessage(
    FORMAT_MESSAGE_FROM_SYSTEM,
    NULL,
    GetLastError(),
    0,
    zBufOut,
    nBuf-1,
    0
  );
}
void *winDlSym(sqlite3_vfs *pVfs, void *pHandle, const char *zSymbol){
#if OS_WINCE
  /* The GetProcAddressA() routine is only available on wince. */
  return GetProcAddressA((HANDLE)pHandle, zSymbol);
#else
  /* All other windows platforms expect GetProcAddress() to take
  ** an Ansi string regardless of the _UNICODE setting */
  return GetProcAddress((HANDLE)pHandle, zSymbol);
#endif
}
void winDlClose(sqlite3_vfs *pVfs, void *pHandle){
  FreeLibrary((HANDLE)pHandle);
}
#else /* if SQLITE_OMIT_LOAD_EXTENSION is defined: */
  #define winDlOpen  0
  #define winDlError 0
  #define winDlSym   0
  #define winDlClose 0
#endif


/*



** Write up to nBuf bytes of randomness into zBuf.
*/




static int winRandomness(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
  if( sizeof(LPSYSTEMTIME)>=nBuf ){








    GetSystemTime((LPSYSTEMTIME)zBuf);
    return sizeof(LPSYSTEMTIME);
  }else{
    return 0;
  }
}


/*
** Sleep for a little while.  Return the amount of time slept.
*/
static int winSleep(sqlite3_vfs *pVfs, int microsec){
  Sleep((microsec+999)/1000);
  return ((microsec+999)/1000)*1000;
}































































/*
** The following variable, if set to a non-zero value, becomes the result
** returned from sqlite3OsCurrentTime().  This is used for testing.
*/
#ifdef SQLITE_TEST
int sqlite3_current_time = 0;
................................................................................
#endif

/*
** Find the current time (in Universal Coordinated Time).  Write the
** current time and date as a Julian Day number into *prNow and
** return 0.  Return 1 if the time and date cannot be found.
*/
int winCurrentTime(sqlite3_vfs *pVfs, double *prNow){
  FILETIME ft;
  /* FILETIME structure is a 64-bit value representing the number of 
     100-nanosecond intervals since January 1, 1601 (= JD 2305813.5). 
  */
  double now;
#if OS_WINCE
  SYSTEMTIME time;
................................................................................
#ifdef SQLITE_TEST
  if( sqlite3_current_time ){
    *prNow = sqlite3_current_time/86400.0 + 2440587.5;
  }
#endif
  return 0;
}


/*

** Return a pointer to the sqlite3DefaultVfs structure.   We use
** a function rather than give the structure global scope because
** some compilers (MSVC) do not allow forward declarations of
** initialized structures.
*/


sqlite3_vfs *sqlite3OsDefaultVfs(void){
  static sqlite3_vfs winVfs = {
    1,                 /* iVersion */
    sizeof(winFile),   /* szOsFile */
    MAX_PATH,          /* mxPathname */
    0,                 /* nRef */
    0,                 /* vfsMutex */
    0,                 /* pNext */
    "win32",           /* zName */
    0,                 /* pAppData */
  




    winOpen,           /* xOpen */
    winDelete,         /* xDelete */
    winAccess,         /* xAccess */
    winGetTempName,    /* xGetTempName */
    winFullPathname,   /* xFullPathname */
    winDlOpen,         /* xDlOpen */
    winDlError,        /* xDlError */
    winDlSym,          /* xDlSym */
    winDlClose,        /* xDlClose */
    winRandomness,     /* xRandomness */
    winSleep,          /* xSleep */
    winCurrentTime     /* xCurrentTime */













  };

  

  return &winVfs;
}



















#endif /* OS_WIN */

** The pager is used to access a database disk file.  It implements
** atomic commit and rollback through the use of a journal file that
** is separate from the database file.  The pager also implements file
** locking to prevent two processes from writing the same database
** file simultaneously, or one process from reading the database while
** another is writing.
**
** @(#) $Id: pager.c,v 1.371 2007/08/23 14:48:24 danielk1977 Exp $
*/
#ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h"
#include <assert.h>
#include <string.h>

/*
................................................................................
  Pager **ppPager,         /* Return the Pager structure here */
  const char *zFilename,   /* Name of the database file to open */
  int nExtra,              /* Extra bytes append to each in-memory page */
  int flags                /* flags controlling this file */
){
  u8 *pPtr;
  Pager *pPager = 0;
  char *zFullPathname = 0;
  int rc = SQLITE_OK;
  int i;
  int tempFile = 0;
  int memDb = 0;
  int readOnly = 0;
  int useJournal = (flags & PAGER_OMIT_JOURNAL)==0;
  int noReadlock = (flags & PAGER_NO_READLOCK)!=0;
................................................................................
  pPager->stfd = (sqlite3_file*)&pPtr[pVfs->szOsFile*1];
  pPager->jfd = (sqlite3_file*)&pPtr[pVfs->szOsFile*2];
  pPager->zFilename = (char*)&pPtr[pVfs->szOsFile*2+journalFileSize];
  pPager->zDirectory = &pPager->zFilename[pVfs->mxPathname];
  pPager->zJournal = &pPager->zDirectory[pVfs->mxPathname];
  pPager->pVfs = pVfs;

  /* Open the pager file and set zFullPathname to point at malloc()ed 
  ** memory containing the complete filename (i.e. including the directory).
  */
  if( zFilename && zFilename[0] ){
#ifndef SQLITE_OMIT_MEMORYDB
    if( strcmp(zFilename,":memory:")==0 ){
      memDb = 1;
      pPager->zFilename[0] = '\0';
    }else
................................................................................
    pPager->state = PAGER_EXCLUSIVE;
  }

  if( pPager && rc==SQLITE_OK ){
    pPager->pTmpSpace = (char *)sqlite3_malloc(SQLITE_DEFAULT_PAGE_SIZE);
  }

  /* If an error occured in either of the blocks above, free the memory 
  ** pointed to by zFullPathname, free the Pager structure and close the 
  ** file. Since the pager is not allocated there is no need to set 
  ** any Pager.errMask variables.
  */
  if( !pPager || !pPager->pTmpSpace ){
    sqlite3OsClose(pPager->fd);
    sqlite3_free(pPager);
    return ((rc==SQLITE_OK)?SQLITE_NOMEM:rc);
  }

  PAGERTRACE3("OPEN %d %s\n", FILEHANDLEID(pPager->fd), zFullPathname);
  IOTRACE(("OPEN %p %s\n", pPager, zFullPathname))

  /* Fill in Pager.zDirectory[] */
  memcpy(pPager->zDirectory, pPager->zFilename, pVfs->mxPathname);
  for(i=strlen(pPager->zDirectory); i>0 && pPager->zDirectory[i-1]!='/'; i--){}
  if( i>0 ) pPager->zDirectory[i-1] = 0;

  /* Fill in Pager.zJournal[] */
................................................................................
/*
** Given a list of pages (connected by the PgHdr.pDirty pointer) write
** every one of those pages out to the database file and mark them all
** as clean.
*/
static int pager_write_pagelist(PgHdr *pList){
  Pager *pPager;

  int rc;

  if( pList==0 ) return SQLITE_OK;
  pPager = pList->pPager;

  /* At this point there may be either a RESERVED or EXCLUSIVE lock on the
  ** database file. If there is already an EXCLUSIVE lock, the following
................................................................................
  */
  rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
  if( rc!=SQLITE_OK ){
    return rc;
  }

  pList = sort_pagelist(pList);




  while( pList ){

    /* If the file has not yet been opened, open it now. */
    if( !pPager->fd->pMethods ){
      assert(pPager->tempFile);
      rc = sqlite3PagerOpentemp(pPager->pVfs, pPager->fd, pPager->zFilename);
      if( rc ) return rc;
    }

    assert( pList->dirty );
    /* If there are dirty pages in the page cache with page numbers greater
    ** than Pager.dbSize, this means sqlite3PagerTruncate() was called to
    ** make the file smaller (presumably by auto-vacuum code). Do not write
    ** any such pages to the file.
    */
    if( pList->pgno<=pPager->dbSize ){
      i64 offset = (pList->pgno-1)*(i64)pPager->pageSize;
................................................................................
    }
#ifndef NDEBUG
    else{
      PAGERTRACE3("NOSTORE %d page %d\n", PAGERID(pPager), pList->pgno);
    }
#endif
    if( rc ) return rc;
    pList->dirty = 0;
#ifdef SQLITE_CHECK_PAGES
    pList->pageHash = pager_pagehash(pList);
#endif
    pList = pList->pDirty;
  }
  return SQLITE_OK;
}
................................................................................
  if( pPg->dirty ){
    int rc;
    assert( pPg->needSync==0 );
    makeClean(pPg);
    pPg->dirty = 1;
    pPg->pDirty = 0;
    rc = pager_write_pagelist( pPg );

    if( rc!=SQLITE_OK ){
      return rc;
    }
  }
  assert( pPg->dirty==0 );

  /* If the page we are recycling is marked as alwaysRollback, then
................................................................................
** Make a page clean.  Clear its dirty bit and remove it from the
** dirty page list.
*/
static void makeClean(PgHdr *pPg){
  if( pPg->dirty ){
    pPg->dirty = 0;
    if( pPg->pDirty ){

      pPg->pDirty->pPrevDirty = pPg->pPrevDirty;
    }
    if( pPg->pPrevDirty ){

      pPg->pPrevDirty->pDirty = pPg->pDirty;
    }else{

      pPg->pPager->pDirty = pPg->pDirty;
    }
  }
}


/*
................................................................................
      if( rc!=SQLITE_OK ) goto sync_exit;
    }
#endif

    /* Write all dirty pages to the database file */
    pPg = pager_get_all_dirty_pages(pPager);
    rc = pager_write_pagelist(pPg);
    if( rc!=SQLITE_OK ) goto sync_exit;




    pPager->pDirty = 0;

    /* Sync the database file. */
    if( !pPager->noSync ){
      rc = sqlite3OsSync(pPager->fd, pPager->sync_flags);
    }
    IOTRACE(("DBSYNC %p\n", pPager))

** The pager is used to access a database disk file.  It implements
** atomic commit and rollback through the use of a journal file that
** is separate from the database file.  The pager also implements file
** locking to prevent two processes from writing the same database
** file simultaneously, or one process from reading the database while
** another is writing.
**
** @(#) $Id: pager.c,v 1.372 2007/08/24 03:51:34 drh Exp $
*/
#ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h"
#include <assert.h>
#include <string.h>

/*
................................................................................
  Pager **ppPager,         /* Return the Pager structure here */
  const char *zFilename,   /* Name of the database file to open */
  int nExtra,              /* Extra bytes append to each in-memory page */
  int flags                /* flags controlling this file */
){
  u8 *pPtr;
  Pager *pPager = 0;

  int rc = SQLITE_OK;
  int i;
  int tempFile = 0;
  int memDb = 0;
  int readOnly = 0;
  int useJournal = (flags & PAGER_OMIT_JOURNAL)==0;
  int noReadlock = (flags & PAGER_NO_READLOCK)!=0;
................................................................................
  pPager->stfd = (sqlite3_file*)&pPtr[pVfs->szOsFile*1];
  pPager->jfd = (sqlite3_file*)&pPtr[pVfs->szOsFile*2];
  pPager->zFilename = (char*)&pPtr[pVfs->szOsFile*2+journalFileSize];
  pPager->zDirectory = &pPager->zFilename[pVfs->mxPathname];
  pPager->zJournal = &pPager->zDirectory[pVfs->mxPathname];
  pPager->pVfs = pVfs;

  /* Open the pager file.

  */
  if( zFilename && zFilename[0] ){
#ifndef SQLITE_OMIT_MEMORYDB
    if( strcmp(zFilename,":memory:")==0 ){
      memDb = 1;
      pPager->zFilename[0] = '\0';
    }else
................................................................................
    pPager->state = PAGER_EXCLUSIVE;
  }

  if( pPager && rc==SQLITE_OK ){
    pPager->pTmpSpace = (char *)sqlite3_malloc(SQLITE_DEFAULT_PAGE_SIZE);
  }

  /* If an error occured in either of the blocks above.
  ** Free the Pager structure and close the file.
  ** Since the pager is not allocated there is no need to set 
  ** any Pager.errMask variables.
  */
  if( !pPager || !pPager->pTmpSpace ){
    sqlite3OsClose(pPager->fd);
    sqlite3_free(pPager);
    return ((rc==SQLITE_OK)?SQLITE_NOMEM:rc);
  }

  PAGERTRACE3("OPEN %d %s\n", FILEHANDLEID(pPager->fd), pPager->zFilename);
  IOTRACE(("OPEN %p %s\n", pPager, pPager->zFilename))

  /* Fill in Pager.zDirectory[] */
  memcpy(pPager->zDirectory, pPager->zFilename, pVfs->mxPathname);
  for(i=strlen(pPager->zDirectory); i>0 && pPager->zDirectory[i-1]!='/'; i--){}
  if( i>0 ) pPager->zDirectory[i-1] = 0;

  /* Fill in Pager.zJournal[] */
................................................................................
/*
** Given a list of pages (connected by the PgHdr.pDirty pointer) write
** every one of those pages out to the database file and mark them all
** as clean.
*/
static int pager_write_pagelist(PgHdr *pList){
  Pager *pPager;
  PgHdr *p;
  int rc;

  if( pList==0 ) return SQLITE_OK;
  pPager = pList->pPager;

  /* At this point there may be either a RESERVED or EXCLUSIVE lock on the
  ** database file. If there is already an EXCLUSIVE lock, the following
................................................................................
  */
  rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
  if( rc!=SQLITE_OK ){
    return rc;
  }

  pList = sort_pagelist(pList);
  for(p=pList; p; p=p->pDirty){
    assert( p->dirty );
    p->dirty = 0;
  }
  while( pList ){

    /* If the file has not yet been opened, open it now. */
    if( !pPager->fd->pMethods ){
      assert(pPager->tempFile);
      rc = sqlite3PagerOpentemp(pPager->pVfs, pPager->fd, pPager->zFilename);
      if( rc ) return rc;
    }


    /* If there are dirty pages in the page cache with page numbers greater
    ** than Pager.dbSize, this means sqlite3PagerTruncate() was called to
    ** make the file smaller (presumably by auto-vacuum code). Do not write
    ** any such pages to the file.
    */
    if( pList->pgno<=pPager->dbSize ){
      i64 offset = (pList->pgno-1)*(i64)pPager->pageSize;
................................................................................
    }
#ifndef NDEBUG
    else{
      PAGERTRACE3("NOSTORE %d page %d\n", PAGERID(pPager), pList->pgno);
    }
#endif
    if( rc ) return rc;

#ifdef SQLITE_CHECK_PAGES
    pList->pageHash = pager_pagehash(pList);
#endif
    pList = pList->pDirty;
  }
  return SQLITE_OK;
}
................................................................................
  if( pPg->dirty ){
    int rc;
    assert( pPg->needSync==0 );
    makeClean(pPg);
    pPg->dirty = 1;
    pPg->pDirty = 0;
    rc = pager_write_pagelist( pPg );
    pPg->dirty = 0;
    if( rc!=SQLITE_OK ){
      return rc;
    }
  }
  assert( pPg->dirty==0 );

  /* If the page we are recycling is marked as alwaysRollback, then
................................................................................
** Make a page clean.  Clear its dirty bit and remove it from the
** dirty page list.
*/
static void makeClean(PgHdr *pPg){
  if( pPg->dirty ){
    pPg->dirty = 0;
    if( pPg->pDirty ){
      assert( pPg->pDirty->pPrevDirty==pPg );
      pPg->pDirty->pPrevDirty = pPg->pPrevDirty;
    }
    if( pPg->pPrevDirty ){
      assert( pPg->pPrevDirty->pDirty==pPg );
      pPg->pPrevDirty->pDirty = pPg->pDirty;
    }else{
      assert( pPg->pPager->pDirty==pPg );
      pPg->pPager->pDirty = pPg->pDirty;
    }
  }
}


/*
................................................................................
      if( rc!=SQLITE_OK ) goto sync_exit;
    }
#endif

    /* Write all dirty pages to the database file */
    pPg = pager_get_all_dirty_pages(pPager);
    rc = pager_write_pagelist(pPg);
    if( rc!=SQLITE_OK ){
      while( pPg && !pPg->dirty ){ pPg = pPg->pDirty; }
      pPager->pDirty = pPg;
      goto sync_exit;
    }
    pPager->pDirty = 0;

    /* Sync the database file. */
    if( !pPager->noSync ){
      rc = sqlite3OsSync(pPager->fd, pPager->sync_flags);
    }
    IOTRACE(("DBSYNC %p\n", pPager))

*/
static const char aDigits[] = "0123456789ABCDEF0123456789abcdef";
static const char aPrefix[] = "-x0\000X0";
static const et_info fmtinfo[] = {
  {  'd', 10, 1, etRADIX,      0,  0 },
  {  's',  0, 4, etSTRING,     0,  0 },
  {  'g',  0, 1, etGENERIC,    30, 0 },
  {  'z',  0, 6, etDYNSTRING,  0,  0 },
  {  'q',  0, 4, etSQLESCAPE,  0,  0 },
  {  'Q',  0, 4, etSQLESCAPE2, 0,  0 },
  {  'w',  0, 4, etSQLESCAPE3, 0,  0 },
  {  'c',  0, 0, etCHARX,      0,  0 },
  {  'o',  8, 0, etRADIX,      0,  2 },
  {  'u', 10, 0, etRADIX,      0,  0 },
  {  'x', 16, 0, etRADIX,      16, 1 },

*/
static const char aDigits[] = "0123456789ABCDEF0123456789abcdef";
static const char aPrefix[] = "-x0\000X0";
static const et_info fmtinfo[] = {
  {  'd', 10, 1, etRADIX,      0,  0 },
  {  's',  0, 4, etSTRING,     0,  0 },
  {  'g',  0, 1, etGENERIC,    30, 0 },
  {  'z',  0, 4, etDYNSTRING,  0,  0 },
  {  'q',  0, 4, etSQLESCAPE,  0,  0 },
  {  'Q',  0, 4, etSQLESCAPE2, 0,  0 },
  {  'w',  0, 4, etSQLESCAPE3, 0,  0 },
  {  'c',  0, 0, etCHARX,      0,  0 },
  {  'o',  8, 0, etRADIX,      0,  2 },
  {  'u', 10, 0, etRADIX,      0,  0 },
  {  'x', 16, 0, etRADIX,      16, 1 },

** 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 1.238 2007/08/23 02:47:53 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_OPEN_READONLY         0x00000001
#define SQLITE_OPEN_READWRITE        0x00000002
#define SQLITE_OPEN_CREATE           0x00000004
#define SQLITE_OPEN_DELETEONCLOSE    0x00000008
#define SQLITE_OPEN_EXCLUSIVE        0x00000010
#define SQLITE_OPEN_MAIN_DB          0x00000100
#define SQLITE_OPEN_TEMP_DB          0x00000200
#define SQLITE_OPEN_MAIN_JOURNAL     0x00000300
#define SQLITE_OPEN_TEMP_JOURNAL     0x00000400
#define SQLITE_OPEN_SUBJOURNAL       0x00000500
#define SQLITE_OPEN_MASTER_JOURNAL   0x00000600

/*
** CAPI3REF: Device Characteristics
**
** The xDeviceCapabilities method of the [sqlite3_io_methods]
** object returns an integer which is a vector of the following
** bit values expressing I/O characteristics of the mass storage
................................................................................
** want to subclass this object by appending additional fields
** of their own use.  The pMethods entry is a pointer to an
** [sqlite3_io_methods] object that defines methods for performing
** I/O operations on the open file.
*/
typedef struct sqlite3_file sqlite3_file;
struct sqlite3_file {
  struct sqlite3_io_methods *pMethods;  /* Methods against the open file */
};

/*
** CAPI3REF: OS Interface File Virtual Methods Object
**
** Every open file in the [sqlite3_vfs] xOpen method contains a pointer to
** an instance of the following object.  This object defines the
................................................................................
** using sqlite3_mutex_alloc() upon first use of the adaptor
** by sqlite3_open_v2() and will deallocate the mutex when the
** last user closes.  In other words, vfsMutex will be allocated
** when nRef transitions from 0 to 1 and will be deallocated when
** nRef transitions from 1 to 0.
**
** Registered vfs modules are kept on a linked list formed by
** the pNext and pPrev pointers.  The [sqlite3_register_vfs()]
** and [sqlite3_unregister_vfs()] interfaces manage this list
** in a thread-safe way.  The [sqlite3_acquire_vfs()] searches the
** list.
**
** The zName field holds the name of the VFS module.  The name must
** be unique across all VFS modules.
**
** SQLite will guarantee that the zFilename string passed to
** xOpen() is a full pathname as generated by xFullPathname() and
** that the string will be valid and unchanged until xClose() is
................................................................................
  int szOsFile;            /* Size of subclassed sqlite3_file */
  int mxPathname;          /* Maximum file pathname length */
  int nRef;                /* Number of references to this structure */
  sqlite3_mutex *vfsMutex; /* A mutex for this VFS */
  sqlite3_vfs *pNext;      /* Next registered VFS */
  const char *zName;       /* Name of this virtual file system */
  void *pAppData;          /* Application context */
  int (*xOpen)(void *pAppData, const char *zName, sqlite3_file*,
               int flags, int *pOutFlags);
  int (*xDelete)(void *pAppData, const char *zName, int syncDir);
  int (*xAccess)(void *pAppData, const char *zName, int flags);
  int (*xGetTempName)(void *pAppData, char *zOut);
  int (*xFullPathname)(void *pAppData, const char *zName, char *zOut);
  void *(*xDlOpen)(void *pAppData, const char *zFilename);
  void (*xDlError)(void *pAppData, int nByte, char *zErrMsg);
  void *(*xDlSym)(void*, const char *zSymbol);
  void (*xDlClose)(void*);
  int (*xRandomness)(void *pAppData, int nByte, char *zOut);
  int (*xSleep)(void *pAppData, int microseconds);
  int (*xCurrentTime)(void *pAppData, double*);
  /* New fields may be appended in figure versions.  The iVersion
  ** value will increment whenever this happens. */
};

#define SQLITE_ACCESS_EXISTS    0
#define SQLITE_ACCESS_READWRITE 1
#define SQLITE_ACCESS_READONLY  2
................................................................................
** parameter "n" is the total size of the buffer, including space for
** the zero terminator.  So the longest string that can be completely
** written will be n-1 characters.
**
** These routines all implement some additional formatting
** options that are useful for constructing SQL statements.
** All of the usual printf formatting options apply.  In addition, there
** is are "%q" and "%Q" options.
**
** The %q option works like %s in that it substitutes a null-terminated
** string from the argument list.  But %q also doubles every '\'' character.
** %q is designed for use inside a string literal.  By doubling each '\''
** character it escapes that character and allows it to be inserted into
** the string.
**
................................................................................
**  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
**  sqlite3_exec(db, zSQL, 0, 0, 0);
**  sqlite3_free(zSQL);
** </pre></blockquote>
**
** The code above will render a correct SQL statement in the zSQL
** variable even if the zText variable is a NULL pointer.




*/
char *sqlite3_mprintf(const char*,...);
char *sqlite3_vmprintf(const char*, va_list);
char *sqlite3_snprintf(int,char*,const char*, ...);

/*
** CAPI3REF: Memory Allocation Subsystem
................................................................................
** memory.  The highwater mark is reset if the argument is
** true.  The SQLite core does not use either of these routines
** and so they do not have to be implemented by the application
** if SQLITE_OMIT_MEMORY_ALLOCATION is defined.  These routines
** are provided by the default memory subsystem for diagnostic
** purposes.
*/
sqlite3_uint64 sqlite3_memory_used(void);
sqlite3_uint64 sqlite3_memory_highwater(int resetFlag);

/*
** CAPI3REF: Memory Allocation Alarms
**
** The [sqlite3_memory_alarm] routine is used to register
** a callback on memory allocation events.
**
................................................................................
** a memory alarm at the soft heap limit and invoking 
** [sqlite3_release_memory()] in the alarm callback.  Application
** programs should not attempt to use the [sqlite3_memory_alarm()]
** interface because doing so will interfere with the
** [sqlite3_soft_heap_limit()] module.
*/
int sqlite3_memory_alarm(
  void(*xCallback)(void *pArg, sqlite3_uint64 used, unsigned int N),
  void *pArg,
  sqlite3_uint64 iThreshold
);


/*
** CAPI3REF: Compile-Time Authorization Callbacks
***
** This routine registers a authorizer callback with the SQLite library.  

** 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 1.239 2007/08/24 03:51:34 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_OPEN_READONLY         0x00000001
#define SQLITE_OPEN_READWRITE        0x00000002
#define SQLITE_OPEN_CREATE           0x00000004
#define SQLITE_OPEN_DELETEONCLOSE    0x00000008
#define SQLITE_OPEN_EXCLUSIVE        0x00000010
#define SQLITE_OPEN_MAIN_DB          0x00000100
#define SQLITE_OPEN_TEMP_DB          0x00000200
#define SQLITE_OPEN_MAIN_JOURNAL     0x00000400
#define SQLITE_OPEN_TEMP_JOURNAL     0x00000800
#define SQLITE_OPEN_SUBJOURNAL       0x00001000
#define SQLITE_OPEN_MASTER_JOURNAL   0x00002000

/*
** CAPI3REF: Device Characteristics
**
** The xDeviceCapabilities method of the [sqlite3_io_methods]
** object returns an integer which is a vector of the following
** bit values expressing I/O characteristics of the mass storage
................................................................................
** want to subclass this object by appending additional fields
** of their own use.  The pMethods entry is a pointer to an
** [sqlite3_io_methods] object that defines methods for performing
** I/O operations on the open file.
*/
typedef struct sqlite3_file sqlite3_file;
struct sqlite3_file {
  const struct sqlite3_io_methods *pMethods;  /* Methods for an open file */
};

/*
** CAPI3REF: OS Interface File Virtual Methods Object
**
** Every open file in the [sqlite3_vfs] xOpen method contains a pointer to
** an instance of the following object.  This object defines the
................................................................................
** using sqlite3_mutex_alloc() upon first use of the adaptor
** by sqlite3_open_v2() and will deallocate the mutex when the
** last user closes.  In other words, vfsMutex will be allocated
** when nRef transitions from 0 to 1 and will be deallocated when
** nRef transitions from 1 to 0.
**
** Registered vfs modules are kept on a linked list formed by
** the pNext pointer.  The [sqlite3_register_vfs()]
** and [sqlite3_unregister_vfs()] interfaces manage this list
** in a thread-safe way.  The [sqlite3_find_vfs()] interface
** searches the list.
**
** The zName field holds the name of the VFS module.  The name must
** be unique across all VFS modules.
**
** SQLite will guarantee that the zFilename string passed to
** xOpen() is a full pathname as generated by xFullPathname() and
** that the string will be valid and unchanged until xClose() is
................................................................................
  int szOsFile;            /* Size of subclassed sqlite3_file */
  int mxPathname;          /* Maximum file pathname length */
  int nRef;                /* Number of references to this structure */
  sqlite3_mutex *vfsMutex; /* A mutex for this VFS */
  sqlite3_vfs *pNext;      /* Next registered VFS */
  const char *zName;       /* Name of this virtual file system */
  void *pAppData;          /* Application context */
  int (*xOpen)(sqlite3_vfs*, const char *zName, sqlite3_file*,
               int flags, int *pOutFlags);
  int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir);
  int (*xAccess)(sqlite3_vfs*, const char *zName, int flags);
  int (*xGetTempName)(sqlite3_vfs*, char *zOut);
  int (*xFullPathname)(sqlite3_vfs*, const char *zName, char *zOut);
  void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename);
  void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg);
  void *(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol);
  void (*xDlClose)(sqlite3_vfs*, void*);
  int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut);
  int (*xSleep)(sqlite3_vfs*, int microseconds);
  int (*xCurrentTime)(sqlite3_vfs*, double*);
  /* New fields may be appended in figure versions.  The iVersion
  ** value will increment whenever this happens. */
};

#define SQLITE_ACCESS_EXISTS    0
#define SQLITE_ACCESS_READWRITE 1
#define SQLITE_ACCESS_READONLY  2
................................................................................
** parameter "n" is the total size of the buffer, including space for
** the zero terminator.  So the longest string that can be completely
** written will be n-1 characters.
**
** These routines all implement some additional formatting
** options that are useful for constructing SQL statements.
** All of the usual printf formatting options apply.  In addition, there
** is are "%q", "%Q", and "%z" options.
**
** The %q option works like %s in that it substitutes a null-terminated
** string from the argument list.  But %q also doubles every '\'' character.
** %q is designed for use inside a string literal.  By doubling each '\''
** character it escapes that character and allows it to be inserted into
** the string.
**
................................................................................
**  char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);
**  sqlite3_exec(db, zSQL, 0, 0, 0);
**  sqlite3_free(zSQL);
** </pre></blockquote>
**
** The code above will render a correct SQL statement in the zSQL
** variable even if the zText variable is a NULL pointer.
**
** The "%z" formatting option works exactly like "%s" with the
** addition that after the string has been read and copied into
** the result, [sqlite3_free()] is called on the input string.
*/
char *sqlite3_mprintf(const char*,...);
char *sqlite3_vmprintf(const char*, va_list);
char *sqlite3_snprintf(int,char*,const char*, ...);

/*
** CAPI3REF: Memory Allocation Subsystem
................................................................................
** memory.  The highwater mark is reset if the argument is
** true.  The SQLite core does not use either of these routines
** and so they do not have to be implemented by the application
** if SQLITE_OMIT_MEMORY_ALLOCATION is defined.  These routines
** are provided by the default memory subsystem for diagnostic
** purposes.
*/
sqlite3_int64 sqlite3_memory_used(void);
sqlite3_int64 sqlite3_memory_highwater(int resetFlag);

/*
** CAPI3REF: Memory Allocation Alarms
**
** The [sqlite3_memory_alarm] routine is used to register
** a callback on memory allocation events.
**
................................................................................
** a memory alarm at the soft heap limit and invoking 
** [sqlite3_release_memory()] in the alarm callback.  Application
** programs should not attempt to use the [sqlite3_memory_alarm()]
** interface because doing so will interfere with the
** [sqlite3_soft_heap_limit()] module.
*/
int sqlite3_memory_alarm(
  void(*xCallback)(void *pArg, sqlite3_int64 used, int N),
  void *pArg,
  sqlite3_int64 iThreshold
);


/*
** CAPI3REF: Compile-Time Authorization Callbacks
***
** This routine registers a authorizer callback with the SQLite library.  

  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  int iDelay;
  const char *zCrashFile;
  int nCrashFile;

  static sqlite3_vfs crashVfs = {
    1,                  /* iVersion */
    0,                  /* szOsFile */
    0,                  /* mxPathname */
    0,                  /* nRef */
    0,                  /* vfsMutex */
................................................................................
    0,                    /* xDlError */
    0,                    /* xDlSym */
    0,                    /* xDlClose */
    cfRandomness,         /* xRandomness */
    cfSleep,              /* xSleep */
    cfCurrentTime         /* xCurrentTime */
  };


  if( crashVfs.pAppData==0 ){
    sqlite3_vfs *pOriginalVfs = sqlite3_vfs_find(0);
    crashVfs.xDlError = pOriginalVfs->xDlError;
    crashVfs.xDlSym = pOriginalVfs->xDlSym;
    crashVfs.xDlClose = pOriginalVfs->xDlClose;
    crashVfs.mxPathname = pOriginalVfs->mxPathname;
................................................................................
    crashVfs.pAppData = (void *)pOriginalVfs;
    crashVfs.szOsFile = sizeof(CrashFile) + pOriginalVfs->szOsFile;
    sqlite3_vfs_release(pOriginalVfs);
    /* sqlite3_vfs_unregister(pOriginalVfs); */
    sqlite3_vfs_register(&crashVfs, 1);
  }

  int iDc = -1;
  int iSectorSize = -1;

  if( objc<3 ){
    Tcl_WrongNumArgs(interp, 1, objv, "?OPTIONS? DELAY CRASHFILE");
    goto error;
  }

  zCrashFile = Tcl_GetStringFromObj(objv[objc-1], &nCrashFile);

  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  int iDelay;
  const char *zCrashFile;
  int nCrashFile, iDc, iSectorSize;

  static sqlite3_vfs crashVfs = {
    1,                  /* iVersion */
    0,                  /* szOsFile */
    0,                  /* mxPathname */
    0,                  /* nRef */
    0,                  /* vfsMutex */
................................................................................
    0,                    /* xDlError */
    0,                    /* xDlSym */
    0,                    /* xDlClose */
    cfRandomness,         /* xRandomness */
    cfSleep,              /* xSleep */
    cfCurrentTime         /* xCurrentTime */
  };


  if( crashVfs.pAppData==0 ){
    sqlite3_vfs *pOriginalVfs = sqlite3_vfs_find(0);
    crashVfs.xDlError = pOriginalVfs->xDlError;
    crashVfs.xDlSym = pOriginalVfs->xDlSym;
    crashVfs.xDlClose = pOriginalVfs->xDlClose;
    crashVfs.mxPathname = pOriginalVfs->mxPathname;
................................................................................
    crashVfs.pAppData = (void *)pOriginalVfs;
    crashVfs.szOsFile = sizeof(CrashFile) + pOriginalVfs->szOsFile;
    sqlite3_vfs_release(pOriginalVfs);
    /* sqlite3_vfs_unregister(pOriginalVfs); */
    sqlite3_vfs_register(&crashVfs, 1);
  }

  iDc = -1;
  iSectorSize = -1;

  if( objc<3 ){
    Tcl_WrongNumArgs(interp, 1, objv, "?OPTIONS? DELAY CRASHFILE");
    goto error;
  }

  zCrashFile = Tcl_GetStringFromObj(objv[objc-1], &nCrashFile);

**    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 1.4 2007/08/23 02:47:53 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>
#include <assert.h>

................................................................................
    nFail = sqlite3_memdebug_fail(iFail, iRepeat);
  }
#endif
  Tcl_SetObjResult(interp, Tcl_NewIntObj(nFail));
  return TCL_OK;
}


/*
** Usage:    sqlite3_memdebug_pending
**
** Return the number of successful mallocs remaining before the
** next simulated failure.  Return -1 if no simulated failure is
** currently scheduled.
*/
static int test_memdebug_pending(
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  extern int sqlite3_memdebug_pending(void);
  Tcl_SetObjResult(interp, Tcl_NewIntObj(sqlite3_memdebug_pending()));
  return TCL_OK;
}


/*
** Usage:    sqlite3_memdebug_settitle TITLE
**
** Set a title string stored with each allocation.  The TITLE is
** typically the name of the test that was running when the
** allocation occurred.  The TITLE is stored with the allocation
................................................................................
     { "sqlite3_realloc",            test_realloc                  },
     { "sqlite3_free",               test_free                     },
     { "sqlite3_memory_used",        test_memory_used              },
     { "sqlite3_memory_highwater",   test_memory_highwater         },
     { "sqlite3_memdebug_backtrace", test_memdebug_backtrace       },
     { "sqlite3_memdebug_dump",      test_memdebug_dump            },
     { "sqlite3_memdebug_fail",      test_memdebug_fail            },
     { "sqlite3_memdebug_pending",   test_memdebug_pending         },
     { "sqlite3_memdebug_settitle",  test_memdebug_settitle        },
  };
  int i;
  for(i=0; i<sizeof(aObjCmd)/sizeof(aObjCmd[0]); i++){
    Tcl_CreateObjCommand(interp, aObjCmd[i].zName, aObjCmd[i].xProc, 0, 0);
  }
  return TCL_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 1.5 2007/08/24 03:51:34 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>
#include <assert.h>

................................................................................
    nFail = sqlite3_memdebug_fail(iFail, iRepeat);
  }
#endif
  Tcl_SetObjResult(interp, Tcl_NewIntObj(nFail));
  return TCL_OK;
}





















/*
** Usage:    sqlite3_memdebug_settitle TITLE
**
** Set a title string stored with each allocation.  The TITLE is
** typically the name of the test that was running when the
** allocation occurred.  The TITLE is stored with the allocation
................................................................................
     { "sqlite3_realloc",            test_realloc                  },
     { "sqlite3_free",               test_free                     },
     { "sqlite3_memory_used",        test_memory_used              },
     { "sqlite3_memory_highwater",   test_memory_highwater         },
     { "sqlite3_memdebug_backtrace", test_memdebug_backtrace       },
     { "sqlite3_memdebug_dump",      test_memdebug_dump            },
     { "sqlite3_memdebug_fail",      test_memdebug_fail            },

     { "sqlite3_memdebug_settitle",  test_memdebug_settitle        },
  };
  int i;
  for(i=0; i<sizeof(aObjCmd)/sizeof(aObjCmd[0]); i++){
    Tcl_CreateObjCommand(interp, aObjCmd[i].zName, aObjCmd[i].xProc, 0, 0);
  }
  return TCL_OK;
}

  int n;
  

  if( p!=0 ){
    n = sqlite3_column_count(pStmt);
    if( N<n && N>=0 ){
      N += useType*n;

      ret = xFunc(&p->aColName[N]);

#if 0
      /* A malloc may have failed inside of the xFunc() call. If this
      ** is the case, clear the mallocFailed flag and return NULL.
      */
      if( p->db && p->db->mallocFailed ){
        p->db->mallocFailed = 0;
        ret = 0;
      }
#endif
    }
  }
  return ret;
}

/*
** Return the name of the Nth column of the result set returned by SQL

  int n;
  

  if( p!=0 ){
    n = sqlite3_column_count(pStmt);
    if( N<n && N>=0 ){
      N += useType*n;
      sqlite3_mutex_enter(p->db->mutex);
      ret = xFunc(&p->aColName[N]);


      /* A malloc may have failed inside of the xFunc() call. If this
      ** is the case, clear the mallocFailed flag and return NULL.
      */
      if( p->db && p->db->mallocFailed ){
        p->db->mallocFailed = 0;
        ret = 0;
      }
      sqlite3_mutex_leave(p->db->mutex);
    }
  }
  return ret;
}

/*
** Return the name of the Nth column of the result set returned by SQL

** statement. This is now set at compile time, rather than during
** execution of the vdbe program so that sqlite3_column_count() can
** be called on an SQL statement before sqlite3_step().
*/
void sqlite3VdbeSetNumCols(Vdbe *p, int nResColumn){
  Mem *pColName;
  int n;
  sqlite3 *db = p->db;

  releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
  sqlite3_free(p->aColName);
  n = nResColumn*COLNAME_N;
  p->nResColumn = nResColumn;
  p->aColName = pColName = (Mem*)sqlite3DbMallocZero(p->db, sizeof(Mem)*n );
  if( p->aColName==0 ) return;
  while( n-- > 0 ){
    pColName->flags = MEM_Null;
    pColName->db = db;
    pColName++;
  }
}

/*
** Set the name of the idx'th column to be returned by the SQL statement.
** zName must be a pointer to a nul terminated string.

** statement. This is now set at compile time, rather than during
** execution of the vdbe program so that sqlite3_column_count() can
** be called on an SQL statement before sqlite3_step().
*/
void sqlite3VdbeSetNumCols(Vdbe *p, int nResColumn){
  Mem *pColName;
  int n;


  releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
  sqlite3_free(p->aColName);
  n = nResColumn*COLNAME_N;
  p->nResColumn = nResColumn;
  p->aColName = pColName = (Mem*)sqlite3DbMallocZero(p->db, sizeof(Mem)*n );
  if( p->aColName==0 ) return;
  while( n-- > 0 ){
    pColName->flags = MEM_Null;
    pColName->db = p->db;
    pColName++;
  }
}

/*
** Set the name of the idx'th column to be returned by the SQL statement.
** zName must be a pointer to a nul terminated string.

**    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 used to help implement virtual tables.
**
** $Id: vtab.c,v 1.53 2007/08/23 02:47:53 drh Exp $
*/
#ifndef SQLITE_OMIT_VIRTUALTABLE
#include "sqliteInt.h"

static int createModule(
  sqlite3 *db,                    /* Database in which module is registered */
  const char *zName,              /* Name assigned to this module */
  const sqlite3_module *pModule,  /* The definition of the module */
  void *pAux,                     /* Context pointer for xCreate/xConnect */
  void (*xDestroy)(void *)        /* Module destructor function */
) {
  int rc, nName;


  sqlite3_mutex_enter(db->mutex);
  nName = strlen(zName);
  Module *pMod = (Module *)sqlite3DbMallocRaw(db, sizeof(Module) + nName + 1);
  if( pMod ){
    char *zCopy = (char *)(&pMod[1]);
    memcpy(zCopy, zName, nName+1);
    pMod->zName = zCopy;
    pMod->pModule = pModule;
    pMod->pAux = pAux;
    pMod->xDestroy = xDestroy;

**    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 used to help implement virtual tables.
**
** $Id: vtab.c,v 1.54 2007/08/24 03:51:34 drh Exp $
*/
#ifndef SQLITE_OMIT_VIRTUALTABLE
#include "sqliteInt.h"

static int createModule(
  sqlite3 *db,                    /* Database in which module is registered */
  const char *zName,              /* Name assigned to this module */
  const sqlite3_module *pModule,  /* The definition of the module */
  void *pAux,                     /* Context pointer for xCreate/xConnect */
  void (*xDestroy)(void *)        /* Module destructor function */
) {
  int rc, nName;
  Module *pMod;

  sqlite3_mutex_enter(db->mutex);
  nName = strlen(zName);
  pMod = (Module *)sqlite3DbMallocRaw(db, sizeof(Module) + nName + 1);
  if( pMod ){
    char *zCopy = (char *)(&pMod[1]);
    memcpy(zCopy, zName, nName+1);
    pMod->zName = zCopy;
    pMod->pModule = pModule;
    pMod->pAux = pAux;
    pMod->xDestroy = xDestroy;

#    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 for correct handling of disk full
# errors.
# 
# $Id: diskfull.test,v 1.6 2007/04/05 17:15:53 danielk1977 Exp $

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

set sqlite_io_error_persist 0
set sqlite_io_error_hit 0
set sqlite_io_error_pending 0
................................................................................
#   BEGIN;
#     INSERT INTO t3 VALUES( randstr(100, 100), randstr(100, 100) );
#     UPDATE t3 SET a = b;
#   COMMIT;
# }

finish_test

#    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 for correct handling of disk full
# errors.
# 
# $Id: diskfull.test,v 1.7 2007/08/24 03:51:34 drh Exp $

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

set sqlite_io_error_persist 0
set sqlite_io_error_hit 0
set sqlite_io_error_pending 0
................................................................................
#   BEGIN;
#     INSERT INTO t3 VALUES( randstr(100, 100), randstr(100, 100) );
#     UPDATE t3 SET a = b;
#   COMMIT;
# }

finish_test