/*

 ** 2007 August 28

 **

 ** 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.

 **

 *************************************************************************

 **

 ** This file contains the common header for all mutex implementations.

 ** The sqliteInt.h header #includes this file so that it is available

 ** to all source files.  We break it out in an effort to keep the code

 ** better organized.

 **

 ** NOTE:  source files should *not* #include this header file directly.

 ** Source files should #include the sqliteInt.h file and let that file

 ** include this one indirectly.

 **

 ** $Id: mutex.h,v 1.8 2008/06/26 10:41:19 danielk1977 Exp $

 */

 #ifdef SQLITE_MUTEX_APPDEF

 /*

 ** If SQLITE_MUTEX_APPDEF is defined, then this whole module is

 ** omitted and equivalent functionality must be provided by the

 ** application that links against the SQLite library.

 */

 #else

 /*

 ** Figure out what version of the code to use.  The choices are

 **

 **   SQLITE_MUTEX_NOOP         For single-threaded applications that

 **                             do not desire error checking.

 **

 **   SQLITE_MUTEX_NOOP_DEBUG   For single-threaded applications with

 **                             error checking to help verify that mutexes

 **                             are being used correctly even though they

 **                             are not needed.  Used when SQLITE_DEBUG is

 **                             defined on single-threaded builds.

 **

 **   SQLITE_MUTEX_PTHREADS     For multi-threaded applications on Unix.

 **

 **   SQLITE_MUTEX_W32          For multi-threaded applications on Win32.

 **

 **   SQLITE_MUTEX_OS2          For multi-threaded applications on OS/2.

 */

 #define SQLITE_MUTEX_NOOP 1   /* The default */

 #if defined(SQLITE_DEBUG) && !SQLITE_THREADSAFE

 # undef SQLITE_MUTEX_NOOP

 # define SQLITE_MUTEX_NOOP_DEBUG

 #endif

 #if defined(SQLITE_MUTEX_NOOP) && SQLITE_THREADSAFE && SQLITE_OS_UNIX

 # undef SQLITE_MUTEX_NOOP

 # define SQLITE_MUTEX_PTHREADS

 #endif

 #if defined(SQLITE_MUTEX_NOOP) && SQLITE_THREADSAFE && SQLITE_OS_WIN

 # undef SQLITE_MUTEX_NOOP

 # define SQLITE_MUTEX_W32

 #endif

 #if defined(SQLITE_MUTEX_NOOP) && SQLITE_THREADSAFE && SQLITE_OS_OS2

 # undef SQLITE_MUTEX_NOOP

 # define SQLITE_MUTEX_OS2

 #endif

 #if defined(SQLITE_MUTEX_NOOP) && SQLITE_THREADSAFE && SQLITE_OS_SYMBIAN

 # undef SQLITE_MUTEX_NOOP

 # define SQLITE_MUTEX_SYMBIAN

 #endif

 #ifdef SQLITE_MUTEX_NOOP

 /*

 ** If this is a no-op implementation, implement everything as macros.

 */

 #define sqlite3_mutex_alloc(X)    ((sqlite3_mutex*)8)

 #define sqlite3_mutex_free(X)

 #define sqlite3_mutex_enter(X)

 #define sqlite3_mutex_try(X)      SQLITE_OK

 #define sqlite3_mutex_leave(X)

 #define sqlite3_mutex_held(X)     1

 #define sqlite3_mutex_notheld(X)  1

 #define sqlite3MutexAlloc(X)      ((sqlite3_mutex*)8)

 #define sqlite3MutexInit()        SQLITE_OK

 #define sqlite3MutexEnd()

 #endif

 #endif /* SQLITE_MUTEX_APPDEF */