SQLite

** of the source.
*/
static int setDestPgsz(sqlite3_backup *p){
  int rc;
  rc = sqlite3BtreeSetPageSize(p->pDest,sqlite3BtreeGetPageSize(p->pSrc),-1,0);
  return rc;
}

/*
** Check that there is no open read-transaction on the b-tree passed as the
** second argument. If there is not, return SQLITE_OK. Otherwise, if there
** is an open read-transaction, return SQLITE_ERROR and leave an error 
** message in database handle db.
*/
static int checkReadTransaction(sqlite3 *db, Btree *p){
  if( sqlite3BtreeIsInReadTrans(p) ){
    sqlite3ErrorWithMsg(db, SQLITE_ERROR, "destination database is in use");
    return SQLITE_ERROR;
  }
  return SQLITE_OK;
}

/*
** Create an sqlite3_backup process to copy the contents of zSrcDb from
** connection handle pSrcDb to zDestDb in pDestDb. If successful, return
** a pointer to the new sqlite3_backup object.
**
** If an error occurs, NULL is returned and an error code and error message

    p->pSrc = findBtree(pDestDb, pSrcDb, zSrcDb);
    p->pDest = findBtree(pDestDb, pDestDb, zDestDb);
    p->pDestDb = pDestDb;
    p->pSrcDb = pSrcDb;
    p->iNext = 1;
    p->isAttached = 0;

    if( 0==p->pSrc || 0==p->pDest 
     || setDestPgsz(p)==SQLITE_NOMEM 
     || checkReadTransaction(pDestDb, p->pDest)!=SQLITE_OK 
     ){
      /* One (or both) of the named databases did not exist or an OOM
      ** error was hit. Or there is a transaction open on the destination
      ** database. The error has already been written into the pDestDb 
      ** handle. All that is left to do here is free the sqlite3_backup 
      ** structure.  */

      sqlite3_free(p);
      p = 0;
    }
  }
  if( p ){
    p->pSrc->nBackup++;
  }

        CREATE INDEX ${file_dest}.i1 ON t1(a, b);
      " $db_dest
      for {set ii 0} {$ii < $rows_dest} {incr ii} {
        execsql "
          INSERT INTO ${file_dest}.t1 VALUES(1, randstr(1000,1000))
        " $db_dest
      }
      execsql COMMIT $db_dest
    }
  
    # Backup the source database.
    do_test backup-2.$iTest.1 {
      sqlite3_backup B $db_dest $file_dest db main
      while {[B step $nPagePerStep]=="SQLITE_OK"} {}
      B finish

# 2014 November 13
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix backup5

forcedelete test2.db

do_execsql_test 1.0 {
  CREATE TABLE t1(a, b);
  CREATE TABLE t2(a, b);
  INSERT INTO t2 VALUES(1, 1);
  INSERT INTO t2 VALUES(2, 2);
  INSERT INTO t2 VALUES(3, 3);
}

do_test 1.1 {
  forcecopy test.db test.db2
  db eval {
    DROP TABLE t2;
    INSERT INTO t1 VALUES(zeroblob(1000), zeroblob(1000));
    INSERT INTO t1 VALUES(randomblob(1000), randomblob(1000));
  }
} {}

do_test 1.2 {
  sqlite3 db2 test.db2
  set stmt [sqlite3_prepare_v2 db2 "SELECT * FROM t2" -1 dummy]
  sqlite3_step $stmt
} {SQLITE_ROW}

do_test 1.3 {
  list [catch { sqlite3_backup B db2 main db main } msg] $msg
} {1 {sqlite3_backup_init() failed}}

do_test 1.4 {
  sqlite3_errmsg db2
} {destination database is in use}

do_test 1.5 {
  sqlite3_reset $stmt
  sqlite3_backup B db2 main db main
  B step 200
  B finish
} {SQLITE_OK}

do_test 1.6 {
  list [sqlite3_step $stmt] [sqlite3_finalize $stmt]
} {SQLITE_ERROR SQLITE_ERROR}

do_test 1.7 {
  sqlite3_errmsg db2
} {no such table: t2}

finish_test