SQLite

sqlite3_backup **sqlite3PagerBackupPtr(Pager *pPager){
  return &pPager->pBackup;
}

/*
** This function is called when the user invokes "PRAGMA checkpoint".
*/
int sqlite3PagerCheckpoint(Pager *pPager, int nMin, int nMax, int doSync){
  int rc = SQLITE_OK;
  if( pPager->pLog ){
    rc = pager_wait_on_lock(pPager, EXCLUSIVE_LOCK);
    if( rc==SQLITE_OK ){
      u8 *zBuf = (u8 *)pPager->pTmpSpace;
      rc = sqlite3LogCheckpoint(pPager->pLog, pPager->fd, zBuf);
    }

int sqlite3PagerCommitPhaseOne(Pager*,const char *zMaster, int);
int sqlite3PagerSync(Pager *pPager);
int sqlite3PagerCommitPhaseTwo(Pager*);
int sqlite3PagerRollback(Pager*);
int sqlite3PagerOpenSavepoint(Pager *pPager, int n);
int sqlite3PagerSavepoint(Pager *pPager, int op, int iSavepoint);
int sqlite3PagerSharedLock(Pager *pPager);


/* Functions used to query pager state and configuration. */
u8 sqlite3PagerIsreadonly(Pager*);
int sqlite3PagerRefcount(Pager*);
int sqlite3PagerMemUsed(Pager*);
const char *sqlite3PagerFilename(Pager*);
const sqlite3_vfs *sqlite3PagerVfs(Pager*);

      sqlite3VdbeAddOp4(v, OP_String8, 0, 1, 0, zOpt, 0);
      sqlite3VdbeAddOp2(v, OP_ResultRow, 1, 1);
    }
  }else
#endif /* SQLITE_OMIT_COMPILEOPTION_DIAGS */

  if( sqlite3StrICmp(zLeft, "checkpoint")==0 ){
    int nMin = 0;
    int nMax = 0;
    int nosync = 0;

    if( zRight ){
      char *z = zRight;
      sqlite3GetInt32(z, &nMin);
      while( sqlite3Isdigit(*z) ) z++;
      while( *z && !sqlite3Isdigit(*z) ) z++;
      sqlite3GetInt32(z, &nMax);
      while( sqlite3Isdigit(*z) ) z++;
      while( *z && !sqlite3Isdigit(*z) ) z++;
      sqlite3GetInt32(z, &nosync);
    }
    sqlite3VdbeUsesBtree(v, iDb);
    sqlite3VdbeAddOp2(v, OP_Transaction, iDb, 1);
    sqlite3VdbeAddOp3(v, OP_Checkpoint, iDb, nMin, nMax);
  }else

#if defined(SQLITE_DEBUG) || defined(SQLITE_TEST)
  /*
  ** Report the current state of file logs for all databases
  */
  if( sqlite3StrICmp(zLeft, "lock_status")==0 ){

  UPDATE_MAX_BLOBSIZE(pMem);
  if( sqlite3VdbeMemTooBig(pMem) ){
    goto too_big;
  }
  break;
}

/* Opcode: Checkpoint P1 P2 P3 * P5
*/
case OP_Checkpoint: {
  Btree *pBt;                     /* Btree to checkpoint */
  int nMin = pOp->p2;             /* Minimum number of pages to copy */
  int nMax = pOp->p3;             /* Maximum number of pages to copy */
  int doNotSync = pOp->p5;        /* True to sync database */

  assert( pOp->p1>=0 && pOp->p1<db->nDb );
  assert( (p->btreeMask & (1<<pOp->p1))!=0 );
  pBt = db->aDb[pOp->p1].pBt;

  rc = sqlite3PagerCheckpoint(sqlite3BtreePager(pBt), nMin, nMax, !doNotSync);
  break;
};  

#if !defined(SQLITE_OMIT_VACUUM) && !defined(SQLITE_OMIT_ATTACH)
/* Opcode: Vacuum * * * * *
**
** Vacuum the entire database.  This opcode will cause other virtual

    PRAGMA checkpoint;
  }
  file size test.db
} [expr 68*1024]
do_test wal-12.3 {
  execsql { 
    DELETE FROM t1 WHERE rowid<54;
    PRAGMA checkpoint('1 100000');
  }
  file size test.db
} [expr 14*1024]

# Run some "warm-body" tests to ensure that log-summary files with more
# than 256 entries (log summaries that contain index blocks) work Ok.
#

      INSERT INTO t1 SELECT randomblob(900) FROM t1 LIMIT 4;   /* 12 */
      INSERT INTO t1 SELECT randomblob(900) FROM t1 LIMIT 4;   /* 16 */
      INSERT INTO t1 SELECT randomblob(900) FROM t1 LIMIT 4;   /* 20 */
      INSERT INTO t1 SELECT randomblob(900) FROM t1 LIMIT 4;   /* 24 */
      INSERT INTO t1 SELECT randomblob(900) FROM t1 LIMIT 4;   /* 28 */
      INSERT INTO t1 SELECT randomblob(900) FROM t1 LIMIT 4;   /* 32 */

      PRAGMA checkpoint('70 70');
      INSERT INTO t1 VALUES(randomblob(900));
      INSERT INTO t1 VALUES(randomblob(900));
      INSERT INTO t1 VALUES(randomblob(900));
    }
  } {1 {child process exited abnormally}}

  do_test walcrash-5.$i.2 {

      INSERT INTO t1 SELECT randomblob(900) FROM t1 LIMIT 4;   /* 12 */
      INSERT INTO t1 SELECT randomblob(900) FROM t1 LIMIT 4;   /* 16 */
      INSERT INTO t1 SELECT randomblob(900) FROM t1 LIMIT 4;   /* 20 */
      INSERT INTO t1 SELECT randomblob(900) FROM t1 LIMIT 4;   /* 24 */
      INSERT INTO t1 SELECT randomblob(900) FROM t1 LIMIT 4;   /* 28 */
      INSERT INTO t1 SELECT randomblob(900) FROM t1 LIMIT 4;   /* 32 */

      PRAGMA checkpoint('70 70');
      INSERT INTO t1 VALUES(randomblob(900));
      INSERT INTO t1 VALUES(randomblob(900));
      INSERT INTO t1 VALUES(randomblob(900));
    }
  } {1 {child process exited abnormally}}

  do_test walcrash-6.$i.2 {

  } {}

  for {set iTest 1} {$iTest < 100} {incr iTest} {

    do_test walslow-1.seed=$seed.$iTest.1 {
      set w [expr int(rand()*2000)]
      set x [expr int(rand()*2000)]
      set y [expr int(rand()*9)+1]
      set z [expr int(rand()*2)]
      execsql { INSERT INTO t1 VALUES(randomblob($w), randomblob($x)) }
      execsql { PRAGMA integrity_check }
    } {ok}

    do_test walslow-1.seed=$seed.$iTest.2 {
      execsql "PRAGMA checkpoint('$y $y $z')"
      execsql { PRAGMA integrity_check }
    } {ok}

    do_test walslow-1.seed=$seed.$iTest.3 {
      file delete -force testX.db testX.db-wal
      file copy test.db testX.db
      file copy test.db-wal testX.db-wal

    dosql $DB "INSERT INTO t1 VALUES(randomblob(100))"
    dosql $DB "INSERT INTO t1 SELECT md5sum(x) FROM t1"
    dosql $DB COMMIT
  }

  proc checkpointer {DB} {
    while { !$::finished } {
      dosql $DB "PRAGMA checkpoint(32)"
      rest 1000
    }
  }

  proc worker {DB N} {
    set j 0
    while { !$::finished } {