/*

** 2008 Jan 22

**

** 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: fault.c,v 1.10 2008/06/22 12:37:58 drh Exp $

*/

/*

** This file contains code to support the concept of "benign" 

** malloc failures (when the xMalloc() or xRealloc() method of the

** sqlite3_mem_methods structure fails to allocate a block of memory

** and returns 0). 

**

** Most malloc failures are non-benign. After they occur, SQLite

** abandons the current operation and returns an error code (usually

** SQLITE_NOMEM) to the user. However, sometimes a fault is not necessarily

** fatal. For example, if a malloc fails while resizing a hash table, this 

** is completely recoverable simply by not carrying out the resize. The 

** hash table will continue to function normally.  So a malloc failure 

** during a hash table resize is a benign fault.

*/

#include "sqliteInt.h"

#ifndef SQLITE_OMIT_BUILTIN_TEST

/*

** Global variables.

*/

static struct BenignMallocHooks {

  void (*xBenignBegin)(void);

  void (*xBenignEnd)(void);

} hooks;

/*

** Register hooks to call when sqlite3BeginBenignMalloc() and

** sqlite3EndBenignMalloc() are called, respectively.

*/

void sqlite3BenignMallocHooks(

  void (*xBenignBegin)(void),

  void (*xBenignEnd)(void)

){

  hooks.xBenignBegin = xBenignBegin;

  hooks.xBenignEnd = xBenignEnd;

}

/*

** This (sqlite3EndBenignMalloc()) is called by SQLite code to indicate that

** subsequent malloc failures are benign. A call to sqlite3EndBenignMalloc()

** indicates that subsequent malloc failures are non-benign.

*/

void sqlite3BeginBenignMalloc(void){

  if( hooks.xBenignBegin ){

    hooks.xBenignBegin();

  }

}

void sqlite3EndBenignMalloc(void){

  if( hooks.xBenignEnd ){

    hooks.xBenignEnd();

  }

}

#endif   /* #ifndef SQLITE_OMIT_BUILTIN_TEST */