int iIns;
    int testrc = 0;

    testCaseProgress(i, nIter, testCaseNDot(), &iDot);

    /* Restore and open the database. */
    testRestoreDb(DBNAME, "wal");
    testrc = tdb_open("bt", DBNAME, 0, &pDb);
    assert( testrc==0 );

    /* Insert nInsert records into the database. Crash midway through. */
    tdb_bt_prepare_sync_crash(pDb, 1 + (i%(nInsert+2)));
    for(iIns=0; iIns<nInsert; iIns++){
      void *pKey; int nKey;
      void *pVal; int nVal;

    int iIns;
    int testrc = 0;

    testCaseProgress(i, nIter, testCaseNDot(), &iDot);

    /* Restore and open the database. */
    testRestoreDb(DBNAME, "wal");
    testrc = tdb_open("bt safety=2", DBNAME, 0, &pDb);
    assert( testrc==0 );

    /* Insert nInsert records into the database. Crash midway through. */
    tdb_bt_prepare_sync_crash(pDb, 1 + (i%(nInsert+2)));
    for(iIns=0; iIns<nInsert; iIns++){
      void *pKey; int nKey;
      void *pVal; int nVal;

  int rc;
  int i;
  CksumDb *pCksum;
  char *zName;

  zName = getName(zSystem);
  testCaseStart(&rc, zName);
  free(zName);

  pCksum = testCksumArrayNew(pData, 0, nRepeat*100, 100);
  pDb = 0;
  rc = tdb_open(zSystem, 0, 1, &pDb);
  if( pDb && tdb_transaction_support(pDb)==0 ){
    testCaseSkip();
    goto skip_rollback_test;
................................................................................
){
  if( *pRc==0 ){
    int bRun = 1;

    if( zPattern ){
      char *zName = getName(zSystem);
      bRun = testGlobMatch(zPattern, zName);
      free(zName);
    }

    if( bRun ){
      DatasourceDefn defn = { TEST_DATASOURCE_RANDOM, 10, 15, 50, 100 };
      Datasource *pData = testDatasourceNew(&defn);
      *pRc = rollback_test_1(zSystem, pData);
      testDatasourceFree(pData);
    }
  }
}

  int rc;
  int i;
  CksumDb *pCksum;
  char *zName;

  zName = getName(zSystem);
  testCaseStart(&rc, zName);
  testFree(zName);

  pCksum = testCksumArrayNew(pData, 0, nRepeat*100, 100);
  pDb = 0;
  rc = tdb_open(zSystem, 0, 1, &pDb);
  if( pDb && tdb_transaction_support(pDb)==0 ){
    testCaseSkip();
    goto skip_rollback_test;
................................................................................
){
  if( *pRc==0 ){
    int bRun = 1;

    if( zPattern ){
      char *zName = getName(zSystem);
      bRun = testGlobMatch(zPattern, zName);
      testFree(zName);
    }

    if( bRun ){
      DatasourceDefn defn = { TEST_DATASOURCE_RANDOM, 10, 15, 50, 100 };
      Datasource *pData = testDatasourceNew(&defn);
      *pRc = rollback_test_1(zSystem, pData);
      testDatasourceFree(pData);
    }
  }
}

  char *zRet;

  va_copy(copy, ap);
  nByte = vsnprintf(0, 0, zFormat, copy);
  va_end(copy);

  assert( nByte>=0 );
  zRet = (char *)malloc(nByte+1);
  vsnprintf(zRet, nByte+1, zFormat, ap);
  return zRet;
}

char *testMallocPrintf(const char *zFormat, ...){
  va_list ap;
  char *zRet;
................................................................................
**
**   * Test code may assume that allocations may not fail.
**   * Returned memory is always zeroed.
**
** Allocations made using testMalloc() should be freed using testFree().
*/
void *testMalloc(int n){
  void *pRet = malloc(n);
  memset(pRet, 0, n);

  return pRet;
}

void *testMallocCopy(void *pCopy, int nByte){
  void *pRet = testMalloc(nByte);
  memcpy(pRet, pCopy, nByte);
  return pRet;
}

void *testRealloc(void *p, int n){



  return realloc(p, n);







}

/*
** Free an allocation made by an earlier call to testMalloc().
*/
void testFree(void *p){



  free(p);

}

/*
** String zPattern contains a glob pattern. Return true if zStr matches 
** the pattern, or false if it does not.
*/
int testGlobMatch(const char *zPattern, const char *zStr){

  char *zRet;

  va_copy(copy, ap);
  nByte = vsnprintf(0, 0, zFormat, copy);
  va_end(copy);

  assert( nByte>=0 );
  zRet = (char *)testMalloc(nByte+1);
  vsnprintf(zRet, nByte+1, zFormat, ap);
  return zRet;
}

char *testMallocPrintf(const char *zFormat, ...){
  va_list ap;
  char *zRet;
................................................................................
**
**   * Test code may assume that allocations may not fail.
**   * Returned memory is always zeroed.
**
** Allocations made using testMalloc() should be freed using testFree().
*/
void *testMalloc(int n){
  u8 *p = (u8*)malloc(n + 8);
  memset(p, 0, n+8);
  *(int*)p = n;
  return (void*)&p[8];
}

void *testMallocCopy(void *pCopy, int nByte){
  void *pRet = testMalloc(nByte);
  memcpy(pRet, pCopy, nByte);
  return pRet;
}

void *testRealloc(void *ptr, int n){
  if( ptr ){
    u8 *p = (u8*)ptr - 8;
    int nOrig =  *(int*)p;
    p = (u8*)realloc(p, n+8);
    if( nOrig<n ){
      memset(&p[8+nOrig], 0, n-nOrig);
    }
    *(int*)p = n;
    return (void*)&p[8];
  }
  return testMalloc(n);
}

/*
** Free an allocation made by an earlier call to testMalloc().
*/
void testFree(void *ptr){
  if( ptr ){
    u8 *p = (u8*)ptr - 8;
    memset(p, 0x55, *(int*)p + 8);
    free(p);
  }
}

/*
** String zPattern contains a glob pattern. Return true if zStr matches 
** the pattern, or false if it does not.
*/
int testGlobMatch(const char *zPattern, const char *zStr){

** This file contains the TestDb bt wrapper.
*/

#include "lsmtest_tdb.h"
#include "lsmtest.h"
#include <unistd.h>
#include "bt.h"



typedef struct BtDb BtDb;
typedef struct BtFile BtFile;






/*
** Each database or log file opened by a database handle is wrapped by
** an object of the following type.
*/
struct BtFile {
  BtDb *pBt;                      /* Database handle that opened this file */

  bt_file *pFile;                 /* File handle belonging to underlying VFS */
  int nSectorSize;                /* Size of sectors in bytes */
  int nSector;                    /* Allocated size of nSector array */
  u8 **apSector;                  /* Original sector data */
};

/*
................................................................................
  bt_db *pBt;                     /* bt database handle */
  sqlite4_env *pEnv;              /* SQLite environment (for malloc/free) */
  bt_env *pVfs;                   /* Underlying VFS */

  /* Space for bt_fetch() results */
  u8 *aBuffer;                    /* Space to store results */
  int nBuffer;                    /* Allocated size of aBuffer[] in bytes */

  int nRef;




  /* Stuff used for crash test simulation */
  BtFile *apFile[2];              /* Database and log files used by pBt */
  bt_env env;                     /* Private VFS for this object */
  int nCrashSync;                 /* Number of syncs until crash (see above) */
  int bCrash;                     /* True once a crash has been simulated */
};
................................................................................
  p = (BtFile*)testMalloc(sizeof(BtFile));
  if( !p ) return SQLITE4_NOMEM;
  if( flags & BT_OPEN_DATABASE ){
    pBt->apFile[0] = p;
  }else if( flags & BT_OPEN_LOG ){
    pBt->apFile[1] = p;
  }

  p->pBt = pBt; 



  rc = pBt->pVfs->xOpen(pEnv, pVfs, zFile, flags, &p->pFile);
  if( rc!=SQLITE4_OK ){
    testFree(p);
    p = 0;
  }else{
    pBt->nRef++;
................................................................................

  *ppFile = (bt_file*)p;
  return rc;
}

static int btVfsSize(bt_file *pFile, sqlite4_int64 *piRes){
  BtFile *p = (BtFile*)pFile;
  if( p->pBt->bCrash ) return SQLITE4_IOERR;
  return p->pBt->pVfs->xSize(p->pFile, piRes);
}

static int btVfsRead(bt_file *pFile, sqlite4_int64 iOff, void *pBuf, int nBuf){
  BtFile *p = (BtFile*)pFile;
  if( p->pBt->bCrash ) return SQLITE4_IOERR;
  return p->pBt->pVfs->xRead(p->pFile, iOff, pBuf, nBuf);
}

static int btFlushSectors(BtFile *p, int iFile){
  sqlite4_int64 iSz;
  int rc;
  int i;
  u8 *aTmp = 0;
................................................................................
  }

  return rc;
}

static int btVfsWrite(bt_file *pFile, sqlite4_int64 iOff, void *pBuf, int nBuf){
  BtFile *p = (BtFile*)pFile;
  if( p->pBt->bCrash ) return SQLITE4_IOERR;
  if( p->pBt->nCrashSync ){
    btSaveSectors(p, iOff, nBuf);
  }
  return p->pBt->pVfs->xWrite(p->pFile, iOff, pBuf, nBuf);
}

static int btVfsTruncate(bt_file *pFile, sqlite4_int64 iOff){
  BtFile *p = (BtFile*)pFile;
  if( p->pBt->bCrash ) return SQLITE4_IOERR;
  return p->pBt->pVfs->xTruncate(p->pFile, iOff);
}

static int btVfsSync(bt_file *pFile){
  int rc = SQLITE4_OK;
  BtFile *p = (BtFile*)pFile;
  BtDb *pBt = p->pBt;


  if( p->pBt->bCrash ) return SQLITE4_IOERR;
  if( pBt->nCrashSync ){
    pBt->nCrashSync--;
    pBt->bCrash = (pBt->nCrashSync==0);
    if( pBt->bCrash ){
      btFlushSectors(pBt->apFile[0], 0);
      btFlushSectors(pBt->apFile[1], 1);
      rc = SQLITE4_IOERR;
    }else{
      btFlushSectors(p, 0);

    }
  }

  if( rc==SQLITE4_OK ){
    rc = p->pBt->pVfs->xSync(p->pFile);
  }
  return rc;
}

static int btVfsSectorSize(bt_file *pFile){
  BtFile *p = (BtFile*)pFile;
  return p->pBt->pVfs->xSectorSize(p->pFile);
}

static void btDeref(BtDb *p){
  p->nRef--;
  assert( p->nRef>=0 );
  if( p->nRef<=0 ) testFree(p);
}

static int btVfsClose(bt_file *pFile){
  BtFile *p = (BtFile*)pFile;

  int rc;

  btFlushSectors(p, 0);



  testFree(p->apSector);
  rc = p->pBt->pVfs->xClose(p->pFile);

  btDeref(p->pBt);

  testFree(p);
  return rc;
}

static int btVfsUnlink(sqlite4_env *pEnv, bt_env *pVfs, const char *zFile){
  BtDb *pBt = (BtDb*)pVfs->pVfsCtx;
  if( pBt->bCrash ) return SQLITE4_IOERR;
  return pBt->pVfs->xUnlink(pEnv, pBt->pVfs, zFile);
}

static int btVfsLock(bt_file *pFile, int iLock, int eType){
  BtFile *p = (BtFile*)pFile;
  if( p->pBt->bCrash ) return SQLITE4_IOERR;
  return p->pBt->pVfs->xLock(p->pFile, iLock, eType);
}

static int btVfsTestLock(bt_file *pFile, int iLock, int nLock, int eType){
  BtFile *p = (BtFile*)pFile;
  if( p->pBt->bCrash ) return SQLITE4_IOERR;
  return p->pBt->pVfs->xTestLock(p->pFile, iLock, nLock, eType);
}

static int btVfsShmMap(bt_file *pFile, int iChunk, int sz, void **ppOut){
  BtFile *p = (BtFile*)pFile;
  if( p->pBt->bCrash ) return SQLITE4_IOERR;
  return p->pBt->pVfs->xShmMap(p->pFile, iChunk, sz, ppOut);
}

static void btVfsShmBarrier(bt_file *pFile){
  BtFile *p = (BtFile*)pFile;
  return p->pBt->pVfs->xShmBarrier(p->pFile);
}

static int btVfsShmUnmap(bt_file *pFile, int bDelete){
  BtFile *p = (BtFile*)pFile;
  if( p->pBt->bCrash ) return SQLITE4_IOERR;
  return p->pBt->pVfs->xShmUnmap(p->pFile, bDelete);
}

static int bt_close(TestDb *pTestDb){
  BtDb *p = (BtDb*)pTestDb;
  int rc = sqlite4BtClose(p->pBt);
  free(p->aBuffer);



  btDeref(p);
  return rc;
}

static int btMinTransaction(BtDb *p, int iMin, int *piLevel){
  int iLevel;
  int rc = SQLITE4_OK;

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

  if( *p ) return SQLITE4_ERROR;
  *piVal = i;
  return SQLITE4_OK;
}

static int testBtConfigure(bt_db *db, const char *zCfg){
  int rc = SQLITE4_OK;

  if( zCfg ){
    struct CfgParam {
      const char *zParam;
      int eParam;
    } aParam[] = {
      { "safety",         BT_CONTROL_SAFETY },
      { "autockpt",       BT_CONTROL_AUTOCKPT },
      { "multiproc",      BT_CONTROL_MULTIPROC }

    };
    const char *z = zCfg;
    int n = strlen(z);
    char *aSpace;
    const char *zOpt;
    const char *zArg;

................................................................................
      int iVal;
      rc = testArgSelect(aParam, "param", zOpt, &i);
      if( rc!=SQLITE4_OK ) break;

      rc = testParseInt(zArg, &iVal);
      if( rc!=SQLITE4_OK ) break;




      rc = sqlite4BtControl(db, aParam[i].eParam, (void*)&iVal);
      if( rc!=SQLITE4_OK ) break;

    }
    testFree(aSpace);
  }

  return rc;
}

................................................................................
    unlink(zFilename);
    unlink(zLog);
    sqlite3_free(zLog);
  }
  
  rc = sqlite4BtNew(pEnv, 0, &pBt);
  if( rc==SQLITE4_OK ){


    p = (BtDb*)testMalloc(sizeof(BtDb));
    p->base.pMethods = &SqlMethods;
    p->pBt = pBt;
    p->pEnv = pEnv;
    p->nRef = 1;

    p->env.pVfsCtx = (void*)p;
................................................................................
    p->env.xShmMap = btVfsShmMap;
    p->env.xShmBarrier = btVfsShmBarrier;
    p->env.xShmUnmap = btVfsShmUnmap;

    sqlite4BtControl(pBt, BT_CONTROL_GETVFS, (void*)&p->pVfs);
    sqlite4BtControl(pBt, BT_CONTROL_SETVFS, (void*)&p->env);

    rc = testBtConfigure(pBt, zSpec);
    if( rc==SQLITE4_OK ){
      rc = sqlite4BtOpen(pBt, zFilename);
    }






  }

  if( rc!=SQLITE4_OK && p ){
    bt_close(&p->base);
  }

  *ppDb = &p->base;
................................................................................

void tdb_bt_prepare_sync_crash(TestDb *pTestDb, int iSync){
  BtDb *p = (BtDb*)pTestDb;
  assert( pTestDb->pMethods->xClose==bt_close );
  assert( p->bCrash==0 );
  p->nCrashSync = iSync;
}

** This file contains the TestDb bt wrapper.
*/

#include "lsmtest_tdb.h"
#include "lsmtest.h"
#include <unistd.h>
#include "bt.h"

#include <pthread.h>

typedef struct BtDb BtDb;
typedef struct BtFile BtFile;

/* Background checkpointer interface (see implementations below). */
typedef struct bt_ckpter bt_ckpter;
static int bgc_attach(BtDb *pDb, const char*);
static int bgc_detach(BtDb *pDb);

/*
** Each database or log file opened by a database handle is wrapped by
** an object of the following type.
*/
struct BtFile {
  BtDb *pBt;                      /* Database handle that opened this file */
  bt_env *pVfs;                   /* Underlying VFS */
  bt_file *pFile;                 /* File handle belonging to underlying VFS */
  int nSectorSize;                /* Size of sectors in bytes */
  int nSector;                    /* Allocated size of nSector array */
  u8 **apSector;                  /* Original sector data */
};

/*
................................................................................
  bt_db *pBt;                     /* bt database handle */
  sqlite4_env *pEnv;              /* SQLite environment (for malloc/free) */
  bt_env *pVfs;                   /* Underlying VFS */

  /* Space for bt_fetch() results */
  u8 *aBuffer;                    /* Space to store results */
  int nBuffer;                    /* Allocated size of aBuffer[] in bytes */

  int nRef;

  /* Background checkpointer used by mt connections */
  bt_ckpter *pCkpter;

  /* Stuff used for crash test simulation */
  BtFile *apFile[2];              /* Database and log files used by pBt */
  bt_env env;                     /* Private VFS for this object */
  int nCrashSync;                 /* Number of syncs until crash (see above) */
  int bCrash;                     /* True once a crash has been simulated */
};
................................................................................
  p = (BtFile*)testMalloc(sizeof(BtFile));
  if( !p ) return SQLITE4_NOMEM;
  if( flags & BT_OPEN_DATABASE ){
    pBt->apFile[0] = p;
  }else if( flags & BT_OPEN_LOG ){
    pBt->apFile[1] = p;
  }
  if( (flags & BT_OPEN_SHARED)==0 ){
    p->pBt = pBt; 
  }
  p->pVfs = pBt->pVfs; 

  rc = pBt->pVfs->xOpen(pEnv, pVfs, zFile, flags, &p->pFile);
  if( rc!=SQLITE4_OK ){
    testFree(p);
    p = 0;
  }else{
    pBt->nRef++;
................................................................................

  *ppFile = (bt_file*)p;
  return rc;
}

static int btVfsSize(bt_file *pFile, sqlite4_int64 *piRes){
  BtFile *p = (BtFile*)pFile;
  if( p->pBt && p->pBt->bCrash ) return SQLITE4_IOERR;
  return p->pVfs->xSize(p->pFile, piRes);
}

static int btVfsRead(bt_file *pFile, sqlite4_int64 iOff, void *pBuf, int nBuf){
  BtFile *p = (BtFile*)pFile;
  if( p->pBt && p->pBt->bCrash ) return SQLITE4_IOERR;
  return p->pVfs->xRead(p->pFile, iOff, pBuf, nBuf);
}

static int btFlushSectors(BtFile *p, int iFile){
  sqlite4_int64 iSz;
  int rc;
  int i;
  u8 *aTmp = 0;
................................................................................
  }

  return rc;
}

static int btVfsWrite(bt_file *pFile, sqlite4_int64 iOff, void *pBuf, int nBuf){
  BtFile *p = (BtFile*)pFile;
  if( p->pBt && p->pBt->bCrash ) return SQLITE4_IOERR;
  if( p->pBt && p->pBt->nCrashSync ){
    btSaveSectors(p, iOff, nBuf);
  }
  return p->pVfs->xWrite(p->pFile, iOff, pBuf, nBuf);
}

static int btVfsTruncate(bt_file *pFile, sqlite4_int64 iOff){
  BtFile *p = (BtFile*)pFile;
  if( p->pBt && p->pBt->bCrash ) return SQLITE4_IOERR;
  return p->pVfs->xTruncate(p->pFile, iOff);
}

static int btVfsSync(bt_file *pFile){
  int rc = SQLITE4_OK;
  BtFile *p = (BtFile*)pFile;
  BtDb *pBt = p->pBt;

  if( pBt ){
    if( pBt->bCrash ) return SQLITE4_IOERR;
    if( pBt->nCrashSync ){
      pBt->nCrashSync--;
      pBt->bCrash = (pBt->nCrashSync==0);
      if( pBt->bCrash ){
        btFlushSectors(pBt->apFile[0], 0);
        btFlushSectors(pBt->apFile[1], 1);
        rc = SQLITE4_IOERR;
      }else{
        btFlushSectors(p, 0);
      }
    }
  }

  if( rc==SQLITE4_OK ){
    rc = p->pVfs->xSync(p->pFile);
  }
  return rc;
}

static int btVfsSectorSize(bt_file *pFile){
  BtFile *p = (BtFile*)pFile;
  return p->pVfs->xSectorSize(p->pFile);
}

static void btDeref(BtDb *p){
  p->nRef--;
  assert( p->nRef>=0 );
  if( p->nRef<=0 ) testFree(p);
}

static int btVfsClose(bt_file *pFile){
  BtFile *p = (BtFile*)pFile;
  BtDb *pBt = p->pBt;
  int rc;
  if( pBt ){
    btFlushSectors(p, 0);
    if( p==pBt->apFile[0] ) pBt->apFile[0] = 0;
    if( p==pBt->apFile[1] ) pBt->apFile[1] = 0;
  }
  testFree(p->apSector);
  rc = p->pVfs->xClose(p->pFile);
#if 0
  btDeref(p->pBt);
#endif
  testFree(p);
  return rc;
}

static int btVfsUnlink(sqlite4_env *pEnv, bt_env *pVfs, const char *zFile){
  BtDb *pBt = (BtDb*)pVfs->pVfsCtx;
  if( pBt->bCrash ) return SQLITE4_IOERR;
  return pBt->pVfs->xUnlink(pEnv, pBt->pVfs, zFile);
}

static int btVfsLock(bt_file *pFile, int iLock, int eType){
  BtFile *p = (BtFile*)pFile;
  if( p->pBt && p->pBt->bCrash ) return SQLITE4_IOERR;
  return p->pVfs->xLock(p->pFile, iLock, eType);
}

static int btVfsTestLock(bt_file *pFile, int iLock, int nLock, int eType){
  BtFile *p = (BtFile*)pFile;
  if( p->pBt && p->pBt->bCrash ) return SQLITE4_IOERR;
  return p->pVfs->xTestLock(p->pFile, iLock, nLock, eType);
}

static int btVfsShmMap(bt_file *pFile, int iChunk, int sz, void **ppOut){
  BtFile *p = (BtFile*)pFile;
  if( p->pBt && p->pBt->bCrash ) return SQLITE4_IOERR;
  return p->pVfs->xShmMap(p->pFile, iChunk, sz, ppOut);
}

static void btVfsShmBarrier(bt_file *pFile){
  BtFile *p = (BtFile*)pFile;
  return p->pVfs->xShmBarrier(p->pFile);
}

static int btVfsShmUnmap(bt_file *pFile, int bDelete){
  BtFile *p = (BtFile*)pFile;
  if( p->pBt && p->pBt->bCrash ) return SQLITE4_IOERR;
  return p->pVfs->xShmUnmap(p->pFile, bDelete);
}

static int bt_close(TestDb *pTestDb){
  BtDb *p = (BtDb*)pTestDb;
  int rc = sqlite4BtClose(p->pBt);
  free(p->aBuffer);
  if( p->apFile[0] ) p->apFile[0]->pBt = 0;
  if( p->apFile[1] ) p->apFile[1]->pBt = 0;
  bgc_detach(p);
  testFree(p);
  return rc;
}

static int btMinTransaction(BtDb *p, int iMin, int *piLevel){
  int iLevel;
  int rc = SQLITE4_OK;

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

  if( *p ) return SQLITE4_ERROR;
  *piVal = i;
  return SQLITE4_OK;
}

static int testBtConfigure(bt_db *db, const char *zCfg, int *pbMt){
  int rc = SQLITE4_OK;

  if( zCfg ){
    struct CfgParam {
      const char *zParam;
      int eParam;
    } aParam[] = {
      { "safety",         BT_CONTROL_SAFETY },
      { "autockpt",       BT_CONTROL_AUTOCKPT },
      { "multiproc",      BT_CONTROL_MULTIPROC },
      { "mt",             -1 }
    };
    const char *z = zCfg;
    int n = strlen(z);
    char *aSpace;
    const char *zOpt;
    const char *zArg;

................................................................................
      int iVal;
      rc = testArgSelect(aParam, "param", zOpt, &i);
      if( rc!=SQLITE4_OK ) break;

      rc = testParseInt(zArg, &iVal);
      if( rc!=SQLITE4_OK ) break;

      if( aParam[i].eParam<0 ){
        *pbMt = iVal;
      }else{
        rc = sqlite4BtControl(db, aParam[i].eParam, (void*)&iVal);
        if( rc!=SQLITE4_OK ) break;
      }
    }
    testFree(aSpace);
  }

  return rc;
}

................................................................................
    unlink(zFilename);
    unlink(zLog);
    sqlite3_free(zLog);
  }
  
  rc = sqlite4BtNew(pEnv, 0, &pBt);
  if( rc==SQLITE4_OK ){
    int mt = 0;                   /* True for multi-threaded connection */

    p = (BtDb*)testMalloc(sizeof(BtDb));
    p->base.pMethods = &SqlMethods;
    p->pBt = pBt;
    p->pEnv = pEnv;
    p->nRef = 1;

    p->env.pVfsCtx = (void*)p;
................................................................................
    p->env.xShmMap = btVfsShmMap;
    p->env.xShmBarrier = btVfsShmBarrier;
    p->env.xShmUnmap = btVfsShmUnmap;

    sqlite4BtControl(pBt, BT_CONTROL_GETVFS, (void*)&p->pVfs);
    sqlite4BtControl(pBt, BT_CONTROL_SETVFS, (void*)&p->env);

    rc = testBtConfigure(pBt, zSpec, &mt);
    if( rc==SQLITE4_OK ){
      rc = sqlite4BtOpen(pBt, zFilename);
    }

    if( rc==SQLITE4_OK && mt ){
      int nAuto = 0;
      rc = bgc_attach(p, zSpec);
      sqlite4BtControl(pBt, BT_CONTROL_AUTOCKPT, (void*)&nAuto);
    }
  }

  if( rc!=SQLITE4_OK && p ){
    bt_close(&p->base);
  }

  *ppDb = &p->base;
................................................................................

void tdb_bt_prepare_sync_crash(TestDb *pTestDb, int iSync){
  BtDb *p = (BtDb*)pTestDb;
  assert( pTestDb->pMethods->xClose==bt_close );
  assert( p->bCrash==0 );
  p->nCrashSync = iSync;
}

/*************************************************************************
** Beginning of code for background checkpointer.
*/

struct bt_ckpter {
  sqlite4_buffer file;            /* File name */
  sqlite4_buffer spec;            /* Options */
  int nLogsize;                   /* Minimum log size to checkpoint */
  int nRef;                       /* Number of clients */

  int bDoWork;                    /* Set by client threads */
  pthread_t ckpter_thread;        /* Checkpointer thread */
  pthread_cond_t ckpter_cond;     /* Condition var the ckpter waits on */
  pthread_mutex_t ckpter_mutex;   /* Mutex used with ckpter_cond */

  bt_ckpter *pNext;               /* Next object in list at gBgc.pCkpter */
};

static struct GlobalBackgroundCheckpointer {
  bt_ckpter *pCkpter;             /* Linked list of checkpointers */
} gBgc;

static void *bgc_main(void *pArg){
  BtDb *pDb = 0;
  int rc;
  int mt;
  bt_ckpter *pCkpter = (bt_ckpter*)pArg;

  rc = test_bt_open("", (char*)pCkpter->file.p, 0, (TestDb**)&pDb);
  assert( rc==SQLITE4_OK );
  rc = testBtConfigure(pDb->pBt, (char*)pCkpter->spec.p, &mt);

  while( pCkpter->nRef>0 ){
    bt_db *db = pDb->pBt;
    int nLog = 0;

    sqlite4BtBegin(db, 1);
    sqlite4BtCommit(db, 0);
    sqlite4BtControl(db, BT_CONTROL_LOGSIZE, (void*)&nLog);

    if( nLog>=pCkpter->nLogsize ){
      int rc;
      bt_checkpoint ckpt;
      memset(&ckpt, 0, sizeof(bt_checkpoint));
      ckpt.nFrameBuffer = nLog/2;
      rc = sqlite4BtControl(db, BT_CONTROL_CHECKPOINT, (void*)&ckpt);
      assert( rc==SQLITE4_OK );
      sqlite4BtControl(db, BT_CONTROL_LOGSIZE, (void*)&nLog);
    }

    /* The thread will wake up when it is signaled either because another
    ** thread has created some work for this one or because the connection
    ** is being closed.  */
    pthread_mutex_lock(&pCkpter->ckpter_mutex);
    if( pCkpter->bDoWork==0 ){
      pthread_cond_wait(&pCkpter->ckpter_cond, &pCkpter->ckpter_mutex);
    }
    pCkpter->bDoWork = 0;
    pthread_mutex_unlock(&pCkpter->ckpter_mutex);
  }

  if( pDb ) bt_close((TestDb*)pDb);
  return 0;
}

static void bgc_logsize_cb(void *pCtx, int nLogsize){
  bt_ckpter *p = (bt_ckpter*)pCtx;
  if( nLogsize>=p->nLogsize ){
    pthread_mutex_lock(&p->ckpter_mutex);
    p->bDoWork = 1;
    pthread_cond_signal(&p->ckpter_cond);
    pthread_mutex_unlock(&p->ckpter_mutex);
  }
}

static int bgc_attach(BtDb *pDb, const char *zSpec){
  int rc;
  int n;
  bt_info info;
  bt_ckpter *pCkpter;

  /* Figure out the full path to the database opened by handle pDb. */
  info.eType = BT_INFO_FILENAME;
  info.pgno = 0;
  sqlite4_buffer_init(&info.output, 0);
  rc = sqlite4BtControl(pDb->pBt, BT_CONTROL_INFO, (void*)&info);
  if( rc!=SQLITE4_OK ) return rc;

  sqlite4_mutex_enter(sqlite4_mutex_alloc(pDb->pEnv, SQLITE4_MUTEX_STATIC_KV));

  /* Search for an existing bt_ckpter object. */
  n = info.output.n;
  for(pCkpter=gBgc.pCkpter; pCkpter; pCkpter=pCkpter->pNext){
    if( n==pCkpter->file.n && 0==memcmp(info.output.p, pCkpter->file.p, n) ){
      break;
    }
  }

  /* Failed to find a suitable checkpointer. Create a new one. */
  if( pCkpter==0 ){
    bt_logsizecb cb;

    pCkpter = testMalloc(sizeof(bt_ckpter));
    memcpy(&pCkpter->file, &info.output, sizeof(sqlite4_buffer));
    info.output.p = 0;
    pCkpter->pNext = gBgc.pCkpter;
    pCkpter->nLogsize = 1000;
    gBgc.pCkpter = pCkpter;
    pCkpter->nRef = 1;

    sqlite4_buffer_init(&pCkpter->spec, 0);
    rc = sqlite4_buffer_set(&pCkpter->spec, zSpec, strlen(zSpec)+1);
    assert( rc==SQLITE4_OK );

    /* Kick off the checkpointer thread. */
    if( rc==0 ) rc = pthread_cond_init(&pCkpter->ckpter_cond, 0);
    if( rc==0 ) rc = pthread_mutex_init(&pCkpter->ckpter_mutex, 0);
    if( rc==0 ){
      rc = pthread_create(&pCkpter->ckpter_thread, 0, bgc_main, (void*)pCkpter);
    }
    assert( rc==0 ); /* todo: Fix this */

    /* Set up the logsize callback for the client thread */
    cb.pCtx = (void*)pCkpter;
    cb.xLogsize = bgc_logsize_cb;
    sqlite4BtControl(pDb->pBt, BT_CONTROL_LOGSIZECB, (void*)&cb);
  }else{
    pCkpter->nRef++;
  }

  /* Assuming a checkpointer was encountered or effected, attach the 
  ** connection to it.  */
  if( pCkpter ){
    pDb->pCkpter = pCkpter;
  }

  sqlite4_mutex_leave(sqlite4_mutex_alloc(pDb->pEnv, SQLITE4_MUTEX_STATIC_KV));
  sqlite4_buffer_clear(&info.output);
  return rc;
}

static int bgc_detach(BtDb *pDb){
  int rc = SQLITE4_OK;
  bt_ckpter *pCkpter = pDb->pCkpter;
  if( pCkpter ){
    int bShutdown = 0;            /* True if this is the last reference */

    sqlite4_mutex_enter(sqlite4_mutex_alloc(pDb->pEnv,SQLITE4_MUTEX_STATIC_KV));
    pCkpter->nRef--;
    if( pCkpter->nRef==0 ){
      bt_ckpter **pp;

      *pp = pCkpter->pNext;
      for(pp=&gBgc.pCkpter; *pp!=pCkpter; pp=&((*pp)->pNext));
      bShutdown = 1;
    }
    sqlite4_mutex_leave(sqlite4_mutex_alloc(pDb->pEnv,SQLITE4_MUTEX_STATIC_KV));

    if( bShutdown ){
      void *pDummy;

      /* Signal the checkpointer thread. */
      pthread_mutex_lock(&pCkpter->ckpter_mutex);
      pCkpter->bDoWork = 1;
      pthread_cond_signal(&pCkpter->ckpter_cond);
      pthread_mutex_unlock(&pCkpter->ckpter_mutex);

      /* Join the checkpointer thread. */
      pthread_join(pCkpter->ckpter_thread, &pDummy);
      pthread_cond_destroy(&pCkpter->ckpter_cond);
      pthread_mutex_destroy(&pCkpter->ckpter_mutex);

      sqlite4_buffer_clear(&pCkpter->file);
      sqlite4_buffer_clear(&pCkpter->spec);
      testFree(pCkpter);
    }

    pDb->pCkpter = 0;
  }
  return rc;
}

/*
** End of background checkpointer.
*************************************************************************/

  if( nByte>sizeof(aBlob) ) nByte = sizeof(aBlob);
  testPrngArray(iSeed, (unsigned int *)aBlob, (nByte+3)/4);

  sqlite4_result_blob(ctx, aBlob, nByte, SQLITE4_TRANSIENT, 0);
}
static void install_rblob_function4(sqlite4 *db){
  testPrngInit();
  sqlite4_create_function(db, "rblob", 3, SQLITE4_UTF8, 0, rblobFunc4, 0, 0);
}

/* sqlite3 implementation */
static void rblobFunc3(sqlite3_context *ctx, int nArg, sqlite3_value **apArg){
  unsigned char aBlob[1000];

  int iSeed = sqlite3_value_int(apArg[0]);
................................................................................
  if( nRange>0 ){
    iVal = iVal % nRange;
  }
  sqlite4_result_int(ctx, iVal);
}
static void install_rint_function4(sqlite4 *db){
  testPrngInit();
  sqlite4_create_function(db, "rint", 2, SQLITE4_UTF8, 0, rintFunc4, 0, 0);
}
/*
** End of rint() implementations.
*************************************************************************/

/*************************************************************************
** Integer query functions for sqlite3 and src4.
................................................................................

  install_rblob_function4(db);

  zCreateTbl = create_schema_sql(nIdx);
  zInsert = create_insert_sql(nIdx);

  /* Create the db schema and prepare the INSERT statement */
  EXPLODE(  sqlite4_exec(db, zCreateTbl, 0, 0, 0)  );
  EXPLODE(  sqlite4_prepare(db, zInsert, -1, &pInsert, 0)  );

  /* Run the test */
  testTimeInit();
  for(i=0; i<nRow; i++){
    if( (i % nRowPerTrans)==0 ){
      if( i!=0 ) EXPLODE(  sqlite4_exec(db, "COMMIT", 0, 0, 0)  );
      EXPLODE(  sqlite4_exec(db, "BEGIN", 0, 0, 0)  );
    }
    sqlite4_bind_int(pInsert, 1, i);
    sqlite4_step(pInsert);
    EXPLODE(  sqlite4_reset(pInsert)  );
  }
  EXPLODE(  sqlite4_exec(db, "COMMIT", 0, 0, 0)  );

  /* Free all the stuff allocated above */
  sqlite4_finalize(pInsert);
  sqlite4_free(0, zCreateTbl);
  sqlite4_free(0, zInsert);
  sqlite4_close(db);
  nMs = testTimeGet();

  /* Print out the time taken by the test */
  printf("%.3f seconds\n", (double)nMs / 1000.0);
  return 0;
}
static int do_insert1_test3(
................................................................................
  /* Create the db schema and prepare the INSERT statement */
  zSelect = create_select_sql(iIdx);
  EXPLODE(  sqlite4_prepare(db, zSelect, -1, &pSelect, 0)  );

  testTimeInit();
  for(i=0; i<nRow; i++){
    if( (i % nRowPerTrans)==0 ){
      if( i!=0 ) EXPLODE(  sqlite4_exec(db, "COMMIT", 0, 0, 0)  );
      EXPLODE(  sqlite4_exec(db, "BEGIN", 0, 0, 0)  );
    }
    sqlite4_bind_int(pSelect, 1, (i*211)%nTblRow);
    EXPLODE(  SQLITE_ROW!=sqlite4_step(pSelect)  );
    EXPLODE(  sqlite4_reset(pSelect)  );
  }
  EXPLODE(  sqlite4_exec(db, "COMMIT", 0, 0, 0)  );
  nMs = testTimeGet();

  sqlite4_finalize(pSelect);
  sqlite4_close(db);
  sqlite4_free(0, zSelect);

  printf("%.3f seconds\n", (double)nMs / 1000.0);
  return 0;
}
static int do_select1_test3(
  const char *zFile,
................................................................................
    rc = sqlite4_open(0, zFile, &p->db);
    if( rc!=SQLITE4_OK ){
      sqlite4_free(0, p);
      p = 0;
    }else{
      install_rint_function4(p->db);
      if( zConfig ) {
        rc = sqlite4_exec(p->db, zConfig, 0, 0, 0);
      }
    }
    *pp = (SqlDatabase *)p;
  }

  return rc;
}
................................................................................
    SqlStmt *pSql;
    SqlStmt *pNext;
    for(pSql=pDb->pSqlStmt; pSql; pSql=pNext){
      pNext = pSql->pNext;
      sqlite4_finalize((sqlite4_stmt *)pSql->pStmt);
      sqlite4_free(0, pSql);
    }
    sqlite4_close(p->db);
    sqlite4_free(0, p);
  }
}

static int exec_sql(SqlDatabase *pDb, const char *zSql, const char *zBind, ...){
  int rc = 0;
  void *pNewStmt = 0;

  if( nByte>sizeof(aBlob) ) nByte = sizeof(aBlob);
  testPrngArray(iSeed, (unsigned int *)aBlob, (nByte+3)/4);

  sqlite4_result_blob(ctx, aBlob, nByte, SQLITE4_TRANSIENT, 0);
}
static void install_rblob_function4(sqlite4 *db){
  testPrngInit();
  sqlite4_create_function(db, "rblob", 3, 0, rblobFunc4, 0, 0, 0);
}

/* sqlite3 implementation */
static void rblobFunc3(sqlite3_context *ctx, int nArg, sqlite3_value **apArg){
  unsigned char aBlob[1000];

  int iSeed = sqlite3_value_int(apArg[0]);
................................................................................
  if( nRange>0 ){
    iVal = iVal % nRange;
  }
  sqlite4_result_int(ctx, iVal);
}
static void install_rint_function4(sqlite4 *db){
  testPrngInit();
  sqlite4_create_function(db, "rint", 2, 0, rintFunc4, 0, 0, 0);
}
/*
** End of rint() implementations.
*************************************************************************/

/*************************************************************************
** Integer query functions for sqlite3 and src4.
................................................................................

  install_rblob_function4(db);

  zCreateTbl = create_schema_sql(nIdx);
  zInsert = create_insert_sql(nIdx);

  /* Create the db schema and prepare the INSERT statement */
  EXPLODE(  sqlite4_exec(db, zCreateTbl, 0, 0)  );
  EXPLODE(  sqlite4_prepare(db, zInsert, -1, &pInsert, 0)  );

  /* Run the test */
  testTimeInit();
  for(i=0; i<nRow; i++){
    if( (i % nRowPerTrans)==0 ){
      if( i!=0 ) EXPLODE(  sqlite4_exec(db, "COMMIT", 0, 0)  );
      EXPLODE(  sqlite4_exec(db, "BEGIN", 0, 0)  );
    }
    sqlite4_bind_int(pInsert, 1, i);
    sqlite4_step(pInsert);
    EXPLODE(  sqlite4_reset(pInsert)  );
  }
  EXPLODE(  sqlite4_exec(db, "COMMIT", 0, 0)  );

  /* Free all the stuff allocated above */
  sqlite4_finalize(pInsert);
  sqlite4_free(0, zCreateTbl);
  sqlite4_free(0, zInsert);
  sqlite4_close(db, 0);
  nMs = testTimeGet();

  /* Print out the time taken by the test */
  printf("%.3f seconds\n", (double)nMs / 1000.0);
  return 0;
}
static int do_insert1_test3(
................................................................................
  /* Create the db schema and prepare the INSERT statement */
  zSelect = create_select_sql(iIdx);
  EXPLODE(  sqlite4_prepare(db, zSelect, -1, &pSelect, 0)  );

  testTimeInit();
  for(i=0; i<nRow; i++){
    if( (i % nRowPerTrans)==0 ){
      if( i!=0 ) EXPLODE(  sqlite4_exec(db, "COMMIT", 0, 0)  );
      EXPLODE(  sqlite4_exec(db, "BEGIN", 0, 0)  );
    }
    sqlite4_bind_int(pSelect, 1, (i*211)%nTblRow);
    EXPLODE(  SQLITE_ROW!=sqlite4_step(pSelect)  );
    EXPLODE(  sqlite4_reset(pSelect)  );
  }
  EXPLODE(  sqlite4_exec(db, "COMMIT", 0, 0)  );
  nMs = testTimeGet();

  sqlite4_finalize(pSelect);
  sqlite4_close(db, 0);
  sqlite4_free(0, zSelect);

  printf("%.3f seconds\n", (double)nMs / 1000.0);
  return 0;
}
static int do_select1_test3(
  const char *zFile,
................................................................................
    rc = sqlite4_open(0, zFile, &p->db);
    if( rc!=SQLITE4_OK ){
      sqlite4_free(0, p);
      p = 0;
    }else{
      install_rint_function4(p->db);
      if( zConfig ) {
        rc = sqlite4_exec(p->db, zConfig, 0, 0);
      }
    }
    *pp = (SqlDatabase *)p;
  }

  return rc;
}
................................................................................
    SqlStmt *pSql;
    SqlStmt *pNext;
    for(pSql=pDb->pSqlStmt; pSql; pSql=pNext){
      pNext = pSql->pNext;
      sqlite4_finalize((sqlite4_stmt *)pSql->pStmt);
      sqlite4_free(0, pSql);
    }
    sqlite4_close(p->db, 0);
    sqlite4_free(0, p);
  }
}

static int exec_sql(SqlDatabase *pDb, const char *zSql, const char *zBind, ...){
  int rc = 0;
  void *pNewStmt = 0;

**   The third argument is interpreted as a pointer to type (int). The
**   value pointer to is set to the number of uncheckpointed frames
**   that stored in the log file according to the snapshot used by the
**   most recently completed transaction or checkpoint operation.
**
** BT_CONTROL_MULTIPROC:
**   The third argument is interpreted as a pointer to type (int).
**   




*/
#define BT_CONTROL_INFO      7706389
#define BT_CONTROL_SETVFS    7706390
#define BT_CONTROL_GETVFS    7706391
#define BT_CONTROL_SAFETY    7706392
#define BT_CONTROL_AUTOCKPT  7706393
#define BT_CONTROL_LOGSIZE   7706394
#define BT_CONTROL_MULTIPROC 7706395



int sqlite4BtControl(bt_db*, int op, void *pArg);

#define BT_SAFETY_OFF    0
#define BT_SAFETY_NORMAL 1
#define BT_SAFETY_FULL   2

typedef struct bt_info bt_info;
struct bt_info {
  int eType;
  unsigned int pgno;
  sqlite4_buffer output;
};
















/*
** File-system interface.
*/
typedef struct bt_env bt_env;
typedef struct bt_file bt_file;

................................................................................
};

/*
** Flags for xOpen
*/
#define BT_OPEN_DATABASE   0x0001
#define BT_OPEN_LOG        0x0002

#define BT_OPEN_READONLY   0x0004

**   The third argument is interpreted as a pointer to type (int). The
**   value pointer to is set to the number of uncheckpointed frames
**   that stored in the log file according to the snapshot used by the
**   most recently completed transaction or checkpoint operation.
**
** BT_CONTROL_MULTIPROC:
**   The third argument is interpreted as a pointer to type (int).
**
** BT_CONTROL_LOGSIZECB:
**
** BT_CONTROL_CHECKPOINT:
**   
*/
#define BT_CONTROL_INFO       7706389
#define BT_CONTROL_SETVFS     7706390
#define BT_CONTROL_GETVFS     7706391
#define BT_CONTROL_SAFETY     7706392
#define BT_CONTROL_AUTOCKPT   7706393
#define BT_CONTROL_LOGSIZE    7706394
#define BT_CONTROL_MULTIPROC  7706395
#define BT_CONTROL_LOGSIZECB  7706396
#define BT_CONTROL_CHECKPOINT 7706397

int sqlite4BtControl(bt_db*, int op, void *pArg);

#define BT_SAFETY_OFF    0
#define BT_SAFETY_NORMAL 1
#define BT_SAFETY_FULL   2

typedef struct bt_info bt_info;
struct bt_info {
  int eType;
  unsigned int pgno;
  sqlite4_buffer output;
};

#define BT_INFO_PAGEDUMP 1
#define BT_INFO_FILENAME 2

typedef struct bt_logsizecb bt_logsizecb;
struct bt_logsizecb {
  void *pCtx;                     /* A copy of this is passed to xLogsize() */
  void (*xLogsize)(void*, int);   /* Callback function */
};

typedef struct bt_checkpoint bt_checkpoint;
struct bt_checkpoint {
  int nFrameBuffer;               /* Minimum number of frames to leave in log */
  int nCkpt;                      /* OUT: Number of frames checkpointed */
};

/*
** File-system interface.
*/
typedef struct bt_env bt_env;
typedef struct bt_file bt_file;

................................................................................
};

/*
** Flags for xOpen
*/
#define BT_OPEN_DATABASE   0x0001
#define BT_OPEN_LOG        0x0002
#define BT_OPEN_SHARED     0x0004
#define BT_OPEN_READONLY   0x0008

void sqlite4BtPagerSetEnv(BtPager*, bt_env*);

void sqlite4BtPagerSetSafety(BtPager*, int*);
void sqlite4BtPagerSetAutockpt(BtPager*, int*);

void sqlite4BtPagerLogsize(BtPager*, int*);
void sqlite4BtPagerMultiproc(BtPager *pPager, int *piVal);



/*
** End of bt_pager.c interface.
*************************************************************************/

/*************************************************************************
** File-system interface.

void sqlite4BtPagerSetEnv(BtPager*, bt_env*);

void sqlite4BtPagerSetSafety(BtPager*, int*);
void sqlite4BtPagerSetAutockpt(BtPager*, int*);

void sqlite4BtPagerLogsize(BtPager*, int*);
void sqlite4BtPagerMultiproc(BtPager *pPager, int *piVal);
void sqlite4BtPagerLogsizeCb(BtPager *pPager, bt_logsizecb*);
int sqlite4BtPagerCheckpoint(BtPager *pPager, bt_checkpoint*);

/*
** End of bt_pager.c interface.
*************************************************************************/

/*************************************************************************
** File-system interface.

  if( rc==SQLITE4_OK ){
    sqlite4_mutex_enter(pShared->pClientMutex);

    /* If this is a multi-process connection and the shared file-handle
    ** has not yet been opened, open it now. Under the cover of the
    ** client-mutex.  */
    if( pShared->pFile==0 && pShared->bMultiProc ){

      rc = pVfs->xOpen(pEnv, pVfs, pShared->zName, 0, &pShared->pFile);
    }

    if( rc==SQLITE4_OK ){
      if( pShared->pBtFile ){
        p->pBtFile = pShared->pBtFile;
        pShared->pBtFile = p->pBtFile->pNext;
        p->pBtFile->pNext = 0;

  if( rc==SQLITE4_OK ){
    sqlite4_mutex_enter(pShared->pClientMutex);

    /* If this is a multi-process connection and the shared file-handle
    ** has not yet been opened, open it now. Under the cover of the
    ** client-mutex.  */
    if( pShared->pFile==0 && pShared->bMultiProc ){
      int flags = BT_OPEN_SHARED;
      rc = pVfs->xOpen(pEnv, pVfs, pShared->zName, flags, &pShared->pFile);
    }

    if( rc==SQLITE4_OK ){
      if( pShared->pBtFile ){
        p->pBtFile = pShared->pBtFile;
        pShared->pBtFile = p->pBtFile->pNext;
        p->pBtFile->pNext = 0;

  return sqlite4BtPagerSetCookie(db->pPager, iVal);
}

int sqlite4BtGetCookie(bt_db *db, unsigned int *piVal){
  return sqlite4BtPagerGetCookie(db->pPager, piVal);
}

int sqlite4BtControl(bt_db *db, int op, void *pArg){
  int rc = SQLITE4_OK;

  switch( op ){
    case BT_CONTROL_INFO: {
      bt_info *pInfo = (bt_info*)pArg;
      int iTrans = sqlite4BtTransactionLevel(db);
      if( iTrans==0 ) rc = sqlite4BtBegin(db, 1);
      if( rc==SQLITE4_OK ){
        BtPage *pPg = 0;
        rc = sqlite4BtPageGet(db->pPager, pInfo->pgno, &pPg);
        if( rc==SQLITE4_OK ){
          u8 *aData;
................................................................................
          sqlite4_buffer_append(&pInfo->output, "", 1);
          sqlite4BtPageRelease(pPg);
        }
        if( iTrans==0 ) rc = sqlite4BtCommit(db, 0);
      }
      break;
    }


























    case BT_CONTROL_GETVFS: {
      *((bt_env**)pArg) = sqlite4BtPagerGetEnv(db->pPager);
      break;
    }

    case BT_CONTROL_SETVFS: {
................................................................................
    }
                             
    case BT_CONTROL_MULTIPROC: {
      int *pInt = (int*)pArg;
      sqlite4BtPagerMultiproc(db->pPager, pInt);
      break;
    }












  }

  return rc;
}

  return sqlite4BtPagerSetCookie(db->pPager, iVal);
}

int sqlite4BtGetCookie(bt_db *db, unsigned int *piVal){
  return sqlite4BtPagerGetCookie(db->pPager, piVal);
}

static int btControlInfo(bt_db *db, bt_info *pInfo){
  int rc = SQLITE4_OK;

  switch( pInfo->eType ){
    case BT_INFO_PAGEDUMP: {

      int iTrans = sqlite4BtTransactionLevel(db);
      if( iTrans==0 ) rc = sqlite4BtBegin(db, 1);
      if( rc==SQLITE4_OK ){
        BtPage *pPg = 0;
        rc = sqlite4BtPageGet(db->pPager, pInfo->pgno, &pPg);
        if( rc==SQLITE4_OK ){
          u8 *aData;
................................................................................
          sqlite4_buffer_append(&pInfo->output, "", 1);
          sqlite4BtPageRelease(pPg);
        }
        if( iTrans==0 ) rc = sqlite4BtCommit(db, 0);
      }
      break;
    }

    case BT_INFO_FILENAME: {
      const char *zFile;
      zFile = sqlite4BtPagerFilename(db->pPager, BT_PAGERFILE_DATABASE);
      rc = sqlite4_buffer_set(&pInfo->output, zFile, strlen(zFile)+1);
      break;
    }

    default: {
      rc = SQLITE4_ERROR;
      break;
    }
  }
  return rc;
}

int sqlite4BtControl(bt_db *db, int op, void *pArg){
  int rc = SQLITE4_OK;

  switch( op ){
    case BT_CONTROL_INFO: {
      bt_info *pInfo = (bt_info*)pArg;
      rc = btControlInfo(db, pInfo);
      break;
    }

    case BT_CONTROL_GETVFS: {
      *((bt_env**)pArg) = sqlite4BtPagerGetEnv(db->pPager);
      break;
    }

    case BT_CONTROL_SETVFS: {
................................................................................
    }
                             
    case BT_CONTROL_MULTIPROC: {
      int *pInt = (int*)pArg;
      sqlite4BtPagerMultiproc(db->pPager, pInt);
      break;
    }

    case BT_CONTROL_LOGSIZECB: {
      bt_logsizecb *p = (bt_logsizecb*)pArg;
      sqlite4BtPagerLogsizeCb(db->pPager, p);
      break;
    }

    case BT_CONTROL_CHECKPOINT: {
      bt_logsizecb *p = (bt_checkpoint*)pArg;
      rc = sqlite4BtPagerCheckpoint(db->pPager, p);
      break;
    }
  }

  return rc;
}

  BtPage *pDirty;                 /* List of all dirty pages */
  int nTotalRef;                  /* Total number of outstanding page refs */
  int bDoAutoCkpt;                /* Do auto-checkpoint after next unlock */
  BtSavepoint *aSavepoint;        /* Savepoint array */
  int nSavepoint;                 /* Number of entries in aSavepoint array */
  int pgsz;                       /* Page size in bytes */
  int nPg;                        /* Number of pages currently in db file */



};


/**************************************************************************
** Interface to BtPageHash object.
*/

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

/*
** Commit the current write transaction to disk.
*/
static int btCommitTransaction(BtPager *p){
  int rc = SQLITE4_OK;

  BtPage *pPg;
  BtPage *pNext;
  assert( p->iTransactionLevel>=2 );

  btCloseSavepoints(p, 2, 0);

  for(pPg=p->pDirty; pPg; pPg=pNext){
................................................................................
      int nPg = ((pNext==0) ? p->nPg : 0);
      rc = sqlite4BtLogWrite(p->pLog, pPg->pgno, pPg->aData, nPg);
    }
  }
  p->pDirty = 0;
  sqlite4BtLogSnapshotEndWrite(p->pLog);

  if( p->btl.nAutoCkpt && sqlite4BtLogSize(p->pLog)>=p->btl.nAutoCkpt ){


    p->bDoAutoCkpt = 1;
  }




  return rc;
}

static int btLoadPageData(BtPager *p, BtPage *pPg){
  int rc;                         /* Return code */

................................................................................

void sqlite4BtPagerMultiproc(BtPager *pPager, int *piVal){
  if( *piVal==0 || *piVal==1 ){
    pPager->btl.bRequestMultiProc = *piVal;
  }
  *piVal = pPager->btl.bRequestMultiProc;
}












#ifndef NDEBUG
int sqlite4BtPagerRefcount(BtPager *p){
  return p->nTotalRef;
}
#endif

  BtPage *pDirty;                 /* List of all dirty pages */
  int nTotalRef;                  /* Total number of outstanding page refs */
  int bDoAutoCkpt;                /* Do auto-checkpoint after next unlock */
  BtSavepoint *aSavepoint;        /* Savepoint array */
  int nSavepoint;                 /* Number of entries in aSavepoint array */
  int pgsz;                       /* Page size in bytes */
  int nPg;                        /* Number of pages currently in db file */

  void *pLogsizeCtx;              /* A copy of this is passed to xLogsize() */
  void (*xLogsize)(void*, int);   /* Log-size Callback function */
};


/**************************************************************************
** Interface to BtPageHash object.
*/

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

/*
** Commit the current write transaction to disk.
*/
static int btCommitTransaction(BtPager *p){
  int rc = SQLITE4_OK;
  int nLogsize;                   /* Number of frames in log after commit */
  BtPage *pPg;
  BtPage *pNext;
  assert( p->iTransactionLevel>=2 );

  btCloseSavepoints(p, 2, 0);

  for(pPg=p->pDirty; pPg; pPg=pNext){
................................................................................
      int nPg = ((pNext==0) ? p->nPg : 0);
      rc = sqlite4BtLogWrite(p->pLog, pPg->pgno, pPg->aData, nPg);
    }
  }
  p->pDirty = 0;
  sqlite4BtLogSnapshotEndWrite(p->pLog);

  nLogsize = sqlite4BtLogSize(p->pLog);

  if( p->btl.nAutoCkpt && nLogsize>=p->btl.nAutoCkpt ){
    p->bDoAutoCkpt = 1;
  }
  if( p->xLogsize ){
    p->xLogsize(p->pLogsizeCtx, nLogsize);
  }

  return rc;
}

static int btLoadPageData(BtPager *p, BtPage *pPg){
  int rc;                         /* Return code */

................................................................................

void sqlite4BtPagerMultiproc(BtPager *pPager, int *piVal){
  if( *piVal==0 || *piVal==1 ){
    pPager->btl.bRequestMultiProc = *piVal;
  }
  *piVal = pPager->btl.bRequestMultiProc;
}

void sqlite4BtPagerLogsizeCb(BtPager *pPager, bt_logsizecb *p){
  pPager->xLogsize = p->xLogsize;
  pPager->pLogsizeCtx = p->pCtx;
}

int sqlite4BtPagerCheckpoint(BtPager *pPager, bt_checkpoint *pCkpt){
  int rc;
  rc = sqlite4BtLogCheckpoint(pPager->pLog, pCkpt->nFrameBuffer);
  return rc;
}

#ifndef NDEBUG
int sqlite4BtPagerRefcount(BtPager *p){
  return p->nTotalRef;
}
#endif