glibc/nptl/pthread_mutex_lock.c

92 lines
2.5 KiB
C

/* Copyright (C) 2002, 2003 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <errno.h>
#include "pthreadP.h"
#include <lowlevellock.h>
#ifndef LLL_MUTEX_LOCK
# define LLL_MUTEX_LOCK(mutex) lll_mutex_lock (mutex)
#endif
int
__pthread_mutex_lock (mutex)
pthread_mutex_t *mutex;
{
pid_t id = THREAD_GETMEM (THREAD_SELF, tid);
switch (__builtin_expect (mutex->__data.__kind, PTHREAD_MUTEX_TIMED_NP))
{
/* Recursive mutex. */
case PTHREAD_MUTEX_RECURSIVE_NP:
/* Check whether we already hold the mutex. */
if (mutex->__data.__owner == id)
{
/* Just bump the counter. */
if (__builtin_expect (mutex->__data.__count + 1 == 0, 0))
/* Overflow of the counter. */
return EAGAIN;
++mutex->__data.__count;
}
else
{
/* We have to get the mutex. */
LLL_MUTEX_LOCK (mutex->__data.__lock);
/* Record the ownership. */
mutex->__data.__owner = id;
mutex->__data.__count = 1;
#ifndef NO_INCR
++mutex->__data.__nusers;
#endif
}
break;
/* Error checking mutex. */
case PTHREAD_MUTEX_ERRORCHECK_NP:
/* Check whether we already hold the mutex. */
if (mutex->__data.__owner == id)
return EDEADLK;
/* FALLTHROUGH */
default:
/* Correct code cannot set any other type. */
case PTHREAD_MUTEX_TIMED_NP:
case PTHREAD_MUTEX_ADAPTIVE_NP:
/* Normal mutex. */
LLL_MUTEX_LOCK (mutex->__data.__lock);
/* Record the ownership. */
mutex->__data.__owner = id;
#ifndef NO_INCR
++mutex->__data.__nusers;
#endif
break;
}
return 0;
}
#ifndef __pthread_mutex_lock
strong_alias (__pthread_mutex_lock, pthread_mutex_lock)
strong_alias (__pthread_mutex_lock, __pthread_mutex_lock_internal)
#endif