** 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 1.530 2008/11/11 20:51:51 shane 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"

................................................................................
      defragmentPage(pPage);
      top = get2byte(&data[hdr+5]);
      assert( end + sz <= top );
    }
    idx = allocateSpace(pPage, sz);
    assert( idx>0 );
    assert( end <= get2byte(&data[hdr+5]) );


    pPage->nCell++;
    pPage->nFree -= 2;
    memcpy(&data[idx+nSkip], pCell+nSkip, sz-nSkip);
    for(j=end-2, ptr=&data[j]; j>ins; j-=2, ptr-=2){
      ptr[0] = ptr[-2];
      ptr[1] = ptr[-1];
    }

** 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 1.531 2008/11/11 22:18:20 shane 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"

................................................................................
      defragmentPage(pPage);
      top = get2byte(&data[hdr+5]);
      assert( end + sz <= top );
    }
    idx = allocateSpace(pPage, sz);
    assert( idx>0 );
    assert( end <= get2byte(&data[hdr+5]) );
    if (idx+sz > pPage->pBt->usableSize) 
      return SQLITE_CORRUPT_BKPT;
    pPage->nCell++;
    pPage->nFree -= 2;
    memcpy(&data[idx+nSkip], pCell+nSkip, sz-nSkip);
    for(j=end-2, ptr=&data[j]; j>ins; j-=2, ptr-=2){
      ptr[0] = ptr[-2];
      ptr[1] = ptr[-1];
    }

# This file implements regression tests for SQLite library.
#
# This file implements tests to make sure SQLite does not crash or
# segfault if it sees a corrupt database file.  It creates a base
# data base file, then tests that single byte corruptions in 
# increasingly larger quantities are handled gracefully.
#
# $Id: corruptC.test,v 1.3 2008/11/11 20:51:51 shane Exp $

catch {file delete -force test.db test.db-journal test.bu}

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

# Set a uniform random seed
................................................................................
  hexio_write test.db 3714 [format %02x 0x58]
  hexio_write test.db 3746 [format %02x 0x9a]

  sqlite3 db test.db
  catchsql {UPDATE t1 SET y=1}
} {0 {}}













#
# now test for a series of quasi-random seeds
#
for {set tn 0} {$tn<=1024} {incr tn 1} {

  # Set a quasi-random random seed
  expr srand($tn)
................................................................................
      set x {}
    } {}
    do_test corruptC-3.$tn.$i.5 {
      catchsql {SELECT count(*) FROM t2 WHERE x<13}
      set x {}
    } {}
    do_test corruptC-3.$tn.$i.6 {
      catchsql {UPDATE t1 SET y=1}
      set x {}
    } {}
    do_test corruptC-3.$tn.$i.7 {
      catchsql {UPDATE t2 SET y=2}
      set x {}
    } {}

    # check the integrity of the database.
    # once the corruption is detected, we can stop.
    ifcapable {integrityck} {
      set res [ catchsql {PRAGMA integrity_check} ]
................................................................................
    ifcapable {!integrityck} {
      if { $i > 5 } {
        set last -1
      }
    }

    # Check that no page references were leaked.



    do_test corruptC-3.$tn.$i.8 {
      set bt [btree_from_db db]
      db_enter db
      array set stats [btree_pager_stats $bt]
      db_leave db
      set stats(ref)
    } {0}

  }
  # end for i

}
# end for tn

finish_test

# This file implements regression tests for SQLite library.
#
# This file implements tests to make sure SQLite does not crash or
# segfault if it sees a corrupt database file.  It creates a base
# data base file, then tests that single byte corruptions in 
# increasingly larger quantities are handled gracefully.
#
# $Id: corruptC.test,v 1.4 2008/11/11 22:18:20 shane Exp $

catch {file delete -force test.db test.db-journal test.bu}

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

# Set a uniform random seed
................................................................................
  hexio_write test.db 3714 [format %02x 0x58]
  hexio_write test.db 3746 [format %02x 0x9a]

  sqlite3 db test.db
  catchsql {UPDATE t1 SET y=1}
} {0 {}}

# test that a corrupt free cell size is handled (seed 13329)
do_test corruptC-2.3 {
  db close
  copy_file test.bu test.db

  # insert corrupt byte(s)
  hexio_write test.db 1094 [format %02x 0x76]

  sqlite3 db test.db
  catchsql {UPDATE t1 SET y=1}
} {0 {database disk image is malformed}}

#
# now test for a series of quasi-random seeds
#
for {set tn 0} {$tn<=1024} {incr tn 1} {

  # Set a quasi-random random seed
  expr srand($tn)
................................................................................
      set x {}
    } {}
    do_test corruptC-3.$tn.$i.5 {
      catchsql {SELECT count(*) FROM t2 WHERE x<13}
      set x {}
    } {}
    do_test corruptC-3.$tn.$i.6 {
      catchsql {BEGIN; UPDATE t1 SET y=1; ROLLBACK;}
      set x {}
    } {}
    do_test corruptC-3.$tn.$i.7 {
      catchsql {BEGIN; UPDATE t2 SET y=2; ROLLBACK;}
      set x {}
    } {}

    # check the integrity of the database.
    # once the corruption is detected, we can stop.
    ifcapable {integrityck} {
      set res [ catchsql {PRAGMA integrity_check} ]
................................................................................
    ifcapable {!integrityck} {
      if { $i > 5 } {
        set last -1
      }
    }

    # Check that no page references were leaked.
    # TBD:  need to figure out why this doesn't work
    # work with ROLLBACKs...
    if {0} {
      do_test corruptC-3.$tn.$i.8 {
        set bt [btree_from_db db]
        db_enter db
        array set stats [btree_pager_stats $bt]
        db_leave db
        set stats(ref)
      } {0}
    }
  }
  # end for i

}
# end for tn

finish_test