SQLite

/*
** 2004 April 6
**
** 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.
**
*************************************************************************
** $Id: btree.c,v 1.509 2008/09/05 05:02:47 danielk1977 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"

    rc = moveToChild(pCur, pgno);
  }
  if( rc==SQLITE_OK ){
    pCur->idx = pPage->nCell - 1;
    pCur->info.nSize = 0;
    pCur->validNKey = 0;
  }
  return rc;
}

/* Move the cursor to the first entry in the table.  Return SQLITE_OK
** on success.  Set *pRes to 0 if the cursor actually points to something
** or set *pRes to 1 if the table is empty.
*/
int sqlite3BtreeFirst(BtCursor *pCur, int *pRes){

# This file attempts to check the behavior of the SQLite library in 
# an out-of-memory situation. When compiled with -DSQLITE_DEBUG=1, 
# the SQLite library accepts a special command (sqlite3_memdebug_fail N C)
# which causes the N-th malloc to fail.  This special feature is used
# to see what happens in the library if a malloc were to really fail
# due to an out-of-memory situation.
#
# $Id: malloc.test,v 1.65 2008/09/05 05:02:47 danielk1977 Exp $

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


# Only run these tests if memory debugging is turned on.
#

  # a malloc() to allocate space to save the index key. This test case is
  # aimed at testing the response of the library to a failure in that
  # particular malloc() call.
  db eval {SELECT a FROM abc ORDER BY a} {
    db eval {UPDATE abc SET b = b - 1 WHERE a = $a}
  }
}

# This test is designed to test a specific juncture in the sqlite code.
# The database set up by -sqlprep script contains a single table B-Tree
# of height 2. In the -tclbody script, the existing database connection
# is closed and a new one opened and used to insert a new row into the
# table B-Tree. By using a new connection, the outcome of a malloc() 
# failure while seeking to the right-hand side of the B-Tree to insert 
# a new record can be tested.
#
do_malloc_test 26 -sqlprep {
  BEGIN;
  CREATE TABLE t1(a, b);
  INSERT INTO t1 VALUES(1, randomblob(210));
  INSERT INTO t1 VALUES(1, randomblob(210));
  INSERT INTO t1 VALUES(1, randomblob(210));
  INSERT INTO t1 VALUES(1, randomblob(210));
  INSERT INTO t1 VALUES(1, randomblob(210));
  COMMIT;
} -tclbody {
  db close
  sqlite3 db test.db
  db eval { INSERT INTO t1 VALUES(1, randomblob(210)) }
}

# Ensure that no file descriptors were leaked.
do_test malloc-99.X {
  catch {db close}
  set sqlite_open_file_count
} {0}

puts open-file-count=$sqlite_open_file_count
finish_test