**    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.
**
*************************************************************************
** This file implements that page cache.
**
** @(#) $Id: pcache.c,v 1.22 2008/08/28 11:12:09 danielk1977 Exp $
*/
#include "sqliteInt.h"

/*
** A complete page cache is an instance of this structure.
**
** A cache may only be deleted by its owner and while holding the
................................................................................
      for(pPg=pCache->pDirtyTail; pPg && pPg->nRef; pPg=pPg->pPrev);
    }
    if( pPg ){
      int rc;
      pcacheExitMutex();
      rc = pCache->xStress(pCache->pStress, pPg);
      pcacheEnterMutex();
      if( rc!=SQLITE_OK ){
        return rc;
      }
    }
  }

  /* If the global page limit has been reached, try to recycle a page. */
  if( pCache->bPurgeable && pcache.nCurrentPage>=pcache.nMaxPage ){

**    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.
**
*************************************************************************
** This file implements that page cache.
**
** @(#) $Id: pcache.c,v 1.23 2008/08/28 17:46:19 drh Exp $
*/
#include "sqliteInt.h"

/*
** A complete page cache is an instance of this structure.
**
** A cache may only be deleted by its owner and while holding the
................................................................................
      for(pPg=pCache->pDirtyTail; pPg && pPg->nRef; pPg=pPg->pPrev);
    }
    if( pPg ){
      int rc;
      pcacheExitMutex();
      rc = pCache->xStress(pCache->pStress, pPg);
      pcacheEnterMutex();
      if( rc!=SQLITE_OK && rc!=SQLITE_BUSY ){
        return rc;
      }
    }
  }

  /* If the global page limit has been reached, try to recycle a page. */
  if( pCache->bPurgeable && pcache.nCurrentPage>=pcache.nMaxPage ){

#
# This file implements tests to verify that ticket #2409 has been
# fixed. More specifically, they verify that if SQLite cannot
# obtain an EXCLUSIVE lock while trying to spill the cache during
# any statement other than a COMMIT, an I/O error is returned instead
# of SQLITE_BUSY.
#
# $Id: tkt2409.test,v 1.5 2008/08/26 18:05:48 danielk1977 Exp $

# Test Outline:
#
#   tkt-2409-1.*: Cause a cache-spill during an INSERT that is within
#       a db transaction but does not start a statement transaction.
#       Verify that the transaction is automatically rolled back
#       and SQLITE_IOERR_BLOCKED is returned
................................................................................
# statement in which the "I/O error" occured did not open a statement
# transaction, SQLite had no choice but to roll back the transaction.
#
do_test tkt2409-3.4 {
  unread_lock_db
  catchsql { ROLLBACK }
} {0 {}}




do_test tkt2409-4.1 {
  execsql {
    PRAGMA cache_size=20;
    DROP TABLE t1;
    CREATE TABLE t1 (x TEXT UNIQUE NOT NULL);
  }

................................................................................
# Check the integrity of the cache.
#
integrity_check tkt2409-4.3

do_test tkt2409-4.4 {
  catchsql { ROLLBACK }
} {0 {}}


unread_lock_db
db2 close
unset -nocomplain t1
finish_test

#
# This file implements tests to verify that ticket #2409 has been
# fixed. More specifically, they verify that if SQLite cannot
# obtain an EXCLUSIVE lock while trying to spill the cache during
# any statement other than a COMMIT, an I/O error is returned instead
# of SQLITE_BUSY.
#
# $Id: tkt2409.test,v 1.6 2008/08/28 17:46:19 drh Exp $

# Test Outline:
#
#   tkt-2409-1.*: Cause a cache-spill during an INSERT that is within
#       a db transaction but does not start a statement transaction.
#       Verify that the transaction is automatically rolled back
#       and SQLITE_IOERR_BLOCKED is returned
................................................................................
# statement in which the "I/O error" occured did not open a statement
# transaction, SQLite had no choice but to roll back the transaction.
#
do_test tkt2409-3.4 {
  unread_lock_db
  catchsql { ROLLBACK }
} {0 {}}
integrity_check tkt2409-3.5


expr {srand(1)}
do_test tkt2409-4.1 {
  execsql {
    PRAGMA cache_size=20;
    DROP TABLE t1;
    CREATE TABLE t1 (x TEXT UNIQUE NOT NULL);
  }

................................................................................
# Check the integrity of the cache.
#
integrity_check tkt2409-4.3

do_test tkt2409-4.4 {
  catchsql { ROLLBACK }
} {0 {}}
integrity_check tkt2409-4.5

unread_lock_db
db2 close
unset -nocomplain t1
finish_test