sqlite3 *dbSrc;          /* Source database connection */
  sqlite3_file *pSrc;      /* Source file handle */
  sqlite3 *dbDest;         /* Destination database connection */
  sqlite3_file *pDest;     /* Destination file handle */
  u32 szPage;              /* Page size */
  u32 szUsable;            /* Usable bytes on each page */
  u32 nPage;               /* Number of pages */

  u8 *page1;               /* Content of page 1 */
};

/* Store an error message */
static void scrubBackupErr(ScrubState *p, const char *zFormat, ...){
  va_list ap;
  sqlite3_free(p->zErr);
................................................................................
  if( p->rcErr ) return;
  iOff = (pgno-1)*(sqlite3_int64)p->szPage;
  rc = p->pDest->pMethods->xWrite(p->pDest, pData, p->szPage, iOff);
  if( rc!=SQLITE_OK ){
    scrubBackupErr(p, "write failed for page %d", pgno);
    p->rcErr = SQLITE_IOERR;
  }

}

/* Prepare a statement against the "db" database. */
static sqlite3_stmt *scrubBackupPrepare(
  ScrubState *p,      /* Backup context */
  sqlite3 *db,        /* Database to prepare against */
  const char *zSql    /* SQL statement */
................................................................................
       "SELECT rootpage FROM sqlite_master WHERE coalesce(rootpage,0)>0");
  if( pStmt==0 ) goto scrub_abort;
  while( sqlite3_step(pStmt)==SQLITE_ROW ){
    i = (u32)sqlite3_column_int(pStmt, 0);
    scrubBackupBtree(&s, i, 0);
  }
  sqlite3_finalize(pStmt);















scrub_abort:    
  /* Close the destination database without closing the transaction. If we
  ** commit, page zero will be overwritten. */
  sqlite3_close(s.dbDest);

  /* But do close out the read-transaction on the source database */

  sqlite3 *dbSrc;          /* Source database connection */
  sqlite3_file *pSrc;      /* Source file handle */
  sqlite3 *dbDest;         /* Destination database connection */
  sqlite3_file *pDest;     /* Destination file handle */
  u32 szPage;              /* Page size */
  u32 szUsable;            /* Usable bytes on each page */
  u32 nPage;               /* Number of pages */
  u32 iLastPage;           /* Page number of last page written so far*/
  u8 *page1;               /* Content of page 1 */
};

/* Store an error message */
static void scrubBackupErr(ScrubState *p, const char *zFormat, ...){
  va_list ap;
  sqlite3_free(p->zErr);
................................................................................
  if( p->rcErr ) return;
  iOff = (pgno-1)*(sqlite3_int64)p->szPage;
  rc = p->pDest->pMethods->xWrite(p->pDest, pData, p->szPage, iOff);
  if( rc!=SQLITE_OK ){
    scrubBackupErr(p, "write failed for page %d", pgno);
    p->rcErr = SQLITE_IOERR;
  }
  if( pgno>p->iLastPage ) p->iLastPage = pgno;
}

/* Prepare a statement against the "db" database. */
static sqlite3_stmt *scrubBackupPrepare(
  ScrubState *p,      /* Backup context */
  sqlite3 *db,        /* Database to prepare against */
  const char *zSql    /* SQL statement */
................................................................................
       "SELECT rootpage FROM sqlite_master WHERE coalesce(rootpage,0)>0");
  if( pStmt==0 ) goto scrub_abort;
  while( sqlite3_step(pStmt)==SQLITE_ROW ){
    i = (u32)sqlite3_column_int(pStmt, 0);
    scrubBackupBtree(&s, i, 0);
  }
  sqlite3_finalize(pStmt);

  /* If the last page of the input db file is a free-list leaf, then the
  ** backup file on disk is still smaller than the size indicated within 
  ** the database header. In this case, write a page of zeroes to the 
  ** last page of the backup database so that SQLite does not mistakenly
  ** think the db is corrupt.  */
  if( s.iLastPage<s.nPage ){
    u8 *aZero = scrubBackupAllocPage(&s);
    if( aZero ){
      memset(aZero, 0, s.szPage);
      scrubBackupWrite(&s, s.nPage, aZero);
      sqlite3_free(aZero);
    }
  }

scrub_abort:    
  /* Close the destination database without closing the transaction. If we
  ** commit, page zero will be overwritten. */
  sqlite3_close(s.dbDest);

  /* But do close out the read-transaction on the source database */