scuffed-code/icu4c/source/common/umutex.c
1999-11-05 20:02:42 +00:00

170 lines
3.9 KiB
C

/*
*******************************************************************************
* *
* COPYRIGHT: *
* (C) Copyright Taligent, Inc., 1997 *
* (C) Copyright International Business Machines Corporation, 1997-1999 *
* Licensed Material - Program-Property of IBM - All Rights Reserved. *
* US Government Users Restricted Rights - Use, duplication, or disclosure *
* restricted by GSA ADP Schedule Contract with IBM Corp. *
* *
*******************************************************************************
*
* File CMUTEX.C
*
* Modification History:
*
* Date Name Description
* 04/02/97 aliu Creation.
* 04/07/99 srl updated
* 05/13/99 stephen Changed to umutex (from cmutex).
*******************************************************************************
*/
/* Assume POSIX, and modify as necessary below */
#define POSIX
#if defined(_WIN32)
#undef POSIX
#endif
#if defined(macintosh)
#undef POSIX
#endif
#if defined(OS2)
#undef POSIX
#endif
#if defined(POSIX) && !defined(APP_NO_THREADS)
/* Usage: uncomment the following, and breakpoint WeAreDeadlocked to
find reentrant issues. */
/* # define POSIX_DEBUG_REENTRANCY 1 */
# include <pthread.h> /* must be first, so that we get the multithread versions of things. */
# ifdef POSIX_DEBUG_REENTRANCY
pthread_t gLastThread;
bool_t gInMutex;
U_EXPORT void WeAreDeadlocked();
void WeAreDeadlocked()
{
puts("ARGH!! We're deadlocked.. break on WeAreDeadlocked() next time.");
}
# endif /* POSIX_DEBUG_REENTRANCY */
#endif /* POSIX && APP_NO_THREADS not defined */
#ifdef _WIN32
# include <WINDOWS.H>
#endif
#include "umutex.h"
#include "cmemory.h"
/* the global mutex. Use it proudly and wash it often. */
UMTX gGlobalMutex = NULL;
void umtx_lock( UMTX *mutex )
{
#ifndef APP_NO_THREADS
if( mutex == NULL )
{
mutex = &gGlobalMutex;
if(*mutex == NULL)
{
umtx_init(NULL);
}
}
#if defined(_WIN32)
EnterCriticalSection((CRITICAL_SECTION*) *mutex);
#elif defined(POSIX)
# ifdef POSIX_DEBUG_REENTRANCY
if(gInMutex == TRUE) // in the mutex -- possible deadlock
if(pthread_equal(gLastThread,pthread_self()))
WeAreDeadlocked();
# endif
pthread_mutex_lock((pthread_mutex_t*) *mutex);
# ifdef POSIX_DEBUG_REENTRANCY
gLastThread = pthread_self();
gInMutex = TRUE;
# endif
#endif
#endif /* APP_NO_THREADS not defined */
}
void umtx_unlock( UMTX* mutex )
{
#ifndef APP_NO_THREADS
if( mutex == NULL )
{
mutex = &gGlobalMutex;
if(*mutex == NULL)
{
return; /* jitterbug 135, fix for multiprocessor machines */
}
}
#if defined(_WIN32)
LeaveCriticalSection((CRITICAL_SECTION*)*mutex);
#elif defined(POSIX)
pthread_mutex_unlock((pthread_mutex_t*)*mutex);
#ifdef POSIX_DEBUG_REENTRANCY
gInMutex = FALSE;
#endif
#endif
#endif /* APP_NO_THREADS not defined */
}
U_CAPI void umtx_init( UMTX *mutex )
{
#ifndef APP_NO_THREADS
if( mutex == NULL ) /* initialize the global mutex */
{
mutex = &gGlobalMutex;
}
if(*mutex != NULL) /* someone already did it. */
return;
#if defined( _WIN32 )
*mutex = icu_malloc(sizeof(CRITICAL_SECTION));
InitializeCriticalSection((CRITICAL_SECTION*)*mutex);
#elif defined( POSIX )
*mutex = icu_malloc(sizeof(pthread_mutex_t));
#if defined(HPUX)
pthread_mutex_init((pthread_mutex_t*)*mutex, pthread_mutexattr_default);
#else
pthread_mutex_init((pthread_mutex_t*)*mutex,NULL);
#endif
# ifdef POSIX_DEBUG_REENTRANCY
gInMutex = FALSE;
# endif
#endif
#endif /* APP_NO_THREADS not defined */
}