+++ /dev/null
-/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
-/* dbus-sysdeps-pthread.c Implements threads using pthreads (internal to libdbus)
- *
- * Copyright (C) 2002, 2003, 2006 Red Hat, Inc.
- *
- * Licensed under the Academic Free License version 2.1
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program 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 General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
- */
-
-#include "dbus-internals.h"
-#include "dbus-sysdeps.h"
-#include "dbus-threads.h"
-
-#include <sys/time.h>
-#include <pthread.h>
-#include <string.h>
-
-#ifdef HAVE_ERRNO_H
-#include <errno.h>
-#endif
-
-typedef struct {
- pthread_mutex_t lock; /**< lock protecting count field */
- volatile int count; /**< count of how many times lock holder has recursively locked */
- volatile pthread_t holder; /**< holder of the lock if count >0,
- valid but arbitrary thread if count
- has ever been >0, uninitialized memory
- if count has never been >0 */
-} DBusMutexPThread;
-
-typedef struct {
- pthread_cond_t cond; /**< the condition */
-} DBusCondVarPThread;
-
-#define DBUS_MUTEX(m) ((DBusMutex*) m)
-#define DBUS_MUTEX_PTHREAD(m) ((DBusMutexPThread*) m)
-
-#define DBUS_COND_VAR(c) ((DBusCondVar*) c)
-#define DBUS_COND_VAR_PTHREAD(c) ((DBusCondVarPThread*) c)
-
-
-#ifdef DBUS_DISABLE_ASSERT
-/* (tmp != 0) is a no-op usage to silence compiler */
-#define PTHREAD_CHECK(func_name, result_or_call) \
- do { int tmp = (result_or_call); if (tmp != 0) {;} } while (0)
-#else
-#define PTHREAD_CHECK(func_name, result_or_call) do { \
- int tmp = (result_or_call); \
- if (tmp != 0) { \
- _dbus_warn_check_failed ("pthread function %s failed with %d %s in %s\n", \
- func_name, tmp, strerror(tmp), _DBUS_FUNCTION_NAME); \
- } \
-} while (0)
-#endif /* !DBUS_DISABLE_ASSERT */
-
-static DBusMutex*
-_dbus_pthread_mutex_new (void)
-{
- DBusMutexPThread *pmutex;
- int result;
-
- pmutex = dbus_new (DBusMutexPThread, 1);
- if (pmutex == NULL)
- return NULL;
-
- result = pthread_mutex_init (&pmutex->lock, NULL);
-
- if (result == ENOMEM || result == EAGAIN)
- {
- dbus_free (pmutex);
- return NULL;
- }
- else
- {
- PTHREAD_CHECK ("pthread_mutex_init", result);
- }
-
- /* Only written */
- pmutex->count = 0;
-
- /* There's no portable way to have a "null" pthread afaik so we
- * can't set pmutex->holder to anything sensible. We only access it
- * once the lock is held (which means we've set it).
- */
-
- return DBUS_MUTEX (pmutex);
-}
-
-static void
-_dbus_pthread_mutex_free (DBusMutex *mutex)
-{
- DBusMutexPThread *pmutex = DBUS_MUTEX_PTHREAD (mutex);
-
- _dbus_assert (pmutex->count == 0);
-
- PTHREAD_CHECK ("pthread_mutex_destroy", pthread_mutex_destroy (&pmutex->lock));
-
- dbus_free (pmutex);
-}
-
-static void
-_dbus_pthread_mutex_lock (DBusMutex *mutex)
-{
- DBusMutexPThread *pmutex = DBUS_MUTEX_PTHREAD (mutex);
- pthread_t self = pthread_self ();
-
- /* If the count is > 0 then someone had the lock, maybe us. If it is
- * 0, then it might immediately change right after we read it,
- * but it will be changed by another thread; i.e. if we read 0,
- * we assume that this thread doesn't have the lock.
- *
- * Not 100% sure this is safe, but ... seems like it should be.
- */
- if (pmutex->count == 0)
- {
- /* We know we don't have the lock; someone may have the lock. */
-
- PTHREAD_CHECK ("pthread_mutex_lock", pthread_mutex_lock (&pmutex->lock));
-
- /* We now have the lock. Count must be 0 since it must be 0 when
- * the lock is released by another thread, and we just now got
- * the lock.
- */
- _dbus_assert (pmutex->count == 0);
-
- pmutex->holder = self;
- pmutex->count = 1;
- }
- else
- {
- /* We know someone had the lock, possibly us. Thus
- * pmutex->holder is not pointing to junk, though it may not be
- * the lock holder anymore if the lock holder is not us. If the
- * lock holder is us, then we definitely have the lock.
- */
-
- if (pthread_equal (pmutex->holder, self))
- {
- /* We already have the lock. */
- _dbus_assert (pmutex->count > 0);
- }
- else
- {
- /* Wait for the lock */
- PTHREAD_CHECK ("pthread_mutex_lock", pthread_mutex_lock (&pmutex->lock));
- pmutex->holder = self;
- _dbus_assert (pmutex->count == 0);
- }
-
- pmutex->count += 1;
- }
-}
-
-static void
-_dbus_pthread_mutex_unlock (DBusMutex *mutex)
-{
- DBusMutexPThread *pmutex = DBUS_MUTEX_PTHREAD (mutex);
-
- _dbus_assert (pmutex->count > 0);
-
- pmutex->count -= 1;
-
- if (pmutex->count == 0)
- PTHREAD_CHECK ("pthread_mutex_unlock", pthread_mutex_unlock (&pmutex->lock));
-
- /* We leave pmutex->holder set to ourselves, its content is undefined if count is 0 */
-}
-
-static DBusCondVar *
-_dbus_pthread_condvar_new (void)
-{
- DBusCondVarPThread *pcond;
- int result;
-
- pcond = dbus_new (DBusCondVarPThread, 1);
- if (pcond == NULL)
- return NULL;
-
- result = pthread_cond_init (&pcond->cond, NULL);
-
- if (result == EAGAIN || result == ENOMEM)
- {
- dbus_free (pcond);
- return NULL;
- }
- else
- {
- PTHREAD_CHECK ("pthread_cond_init", result);
- }
-
- return DBUS_COND_VAR (pcond);
-}
-
-static void
-_dbus_pthread_condvar_free (DBusCondVar *cond)
-{
- DBusCondVarPThread *pcond = DBUS_COND_VAR_PTHREAD (cond);
-
- PTHREAD_CHECK ("pthread_cond_destroy", pthread_cond_destroy (&pcond->cond));
-
- dbus_free (pcond);
-}
-
-static void
-_dbus_pthread_condvar_wait (DBusCondVar *cond,
- DBusMutex *mutex)
-{
- DBusMutexPThread *pmutex = DBUS_MUTEX_PTHREAD (mutex);
- DBusCondVarPThread *pcond = DBUS_COND_VAR_PTHREAD (cond);
- int old_count;
-
- _dbus_assert (pmutex->count > 0);
- _dbus_assert (pthread_equal (pmutex->holder, pthread_self ()));
-
- old_count = pmutex->count;
- pmutex->count = 0; /* allow other threads to lock */
- PTHREAD_CHECK ("pthread_cond_wait", pthread_cond_wait (&pcond->cond, &pmutex->lock));
- _dbus_assert (pmutex->count == 0);
- pmutex->count = old_count;
- pmutex->holder = pthread_self(); /* other threads may have locked the mutex in the meantime */
-}
-
-static dbus_bool_t
-_dbus_pthread_condvar_wait_timeout (DBusCondVar *cond,
- DBusMutex *mutex,
- int timeout_milliseconds)
-{
- DBusMutexPThread *pmutex = DBUS_MUTEX_PTHREAD (mutex);
- DBusCondVarPThread *pcond = DBUS_COND_VAR_PTHREAD (cond);
- struct timeval time_now;
- struct timespec end_time;
- int result;
- int old_count;
-
- _dbus_assert (pmutex->count > 0);
- _dbus_assert (pthread_equal (pmutex->holder, pthread_self ()));
-
- gettimeofday (&time_now, NULL);
-
- end_time.tv_sec = time_now.tv_sec + timeout_milliseconds / 1000;
- end_time.tv_nsec = (time_now.tv_usec + (timeout_milliseconds % 1000) * 1000) * 1000;
- if (end_time.tv_nsec > 1000*1000*1000)
- {
- end_time.tv_sec += 1;
- end_time.tv_nsec -= 1000*1000*1000;
- }
-
- old_count = pmutex->count;
- pmutex->count = 0;
- result = pthread_cond_timedwait (&pcond->cond, &pmutex->lock, &end_time);
-
- if (result != ETIMEDOUT)
- {
- PTHREAD_CHECK ("pthread_cond_timedwait", result);
- }
-
- _dbus_assert (pmutex->count == 0);
- pmutex->count = old_count;
- pmutex->holder = pthread_self(); /* other threads may have locked the mutex in the meantime */
-
- /* return true if we did not time out */
- return result != ETIMEDOUT;
-}
-
-static void
-_dbus_pthread_condvar_wake_one (DBusCondVar *cond)
-{
- DBusCondVarPThread *pcond = DBUS_COND_VAR_PTHREAD (cond);
-
- PTHREAD_CHECK ("pthread_cond_signal", pthread_cond_signal (&pcond->cond));
-}
-
-static void
-_dbus_pthread_condvar_wake_all (DBusCondVar *cond)
-{
- DBusCondVarPThread *pcond = DBUS_COND_VAR_PTHREAD (cond);
-
- PTHREAD_CHECK ("pthread_cond_broadcast", pthread_cond_broadcast (&pcond->cond));
-}
-
-static const DBusThreadFunctions pthread_functions =
-{
- DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_NEW_MASK |
- DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_FREE_MASK |
- DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_LOCK_MASK |
- DBUS_THREAD_FUNCTIONS_RECURSIVE_MUTEX_UNLOCK_MASK |
- DBUS_THREAD_FUNCTIONS_CONDVAR_NEW_MASK |
- DBUS_THREAD_FUNCTIONS_CONDVAR_FREE_MASK |
- DBUS_THREAD_FUNCTIONS_CONDVAR_WAIT_MASK |
- DBUS_THREAD_FUNCTIONS_CONDVAR_WAIT_TIMEOUT_MASK |
- DBUS_THREAD_FUNCTIONS_CONDVAR_WAKE_ONE_MASK|
- DBUS_THREAD_FUNCTIONS_CONDVAR_WAKE_ALL_MASK,
- NULL, NULL, NULL, NULL,
- _dbus_pthread_condvar_new,
- _dbus_pthread_condvar_free,
- _dbus_pthread_condvar_wait,
- _dbus_pthread_condvar_wait_timeout,
- _dbus_pthread_condvar_wake_one,
- _dbus_pthread_condvar_wake_all,
- _dbus_pthread_mutex_new,
- _dbus_pthread_mutex_free,
- _dbus_pthread_mutex_lock,
- _dbus_pthread_mutex_unlock
-};
-
-dbus_bool_t
-_dbus_threads_init_platform_specific (void)
-{
- return dbus_threads_init (&pthread_functions);
-}
projects / monky / blobdiff