/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/*
* Copyright (C) 1999-2008 Novell, Inc. (www.novell.com)
*
* This 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.
*
* This 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 this library. If not, see .
*
*/
#include "evolution-data-server-config.h"
#include "e-cancellable-locks.h"
/**
* SECTION:e-cancellable-locks
* @title: Cancellable Locks
* @short_description: locks, which can listen for a #GCancellable during lock call
*
* An #ECancellableMutex and an #ECancellableRecMutex are similar to
* GLib's #GMutex and #GRecMutex, with one exception, their lock
* function takes also a @GCancellable instance, thus the waiting for a lock
* can be cancelled any time.
**/
static void
cancellable_locks_cancelled_cb (GCancellable *cancellable,
struct _ECancellableLocksBase *base)
{
g_return_if_fail (base != NULL);
/* wake-up any waiting threads */
g_mutex_lock (&base->cond_mutex);
g_cond_broadcast (&base->cond);
g_mutex_unlock (&base->cond_mutex);
}
/**
* e_cancellable_mutex_init:
* @mutex: an #ECancellableMutex instance
*
* Initializes @mutex structure.
*
* Since: 3.8
*
* Deprecated: 3.12: If you think you need this, you're using mutexes wrong.
**/
void
e_cancellable_mutex_init (ECancellableMutex *mutex)
{
g_return_if_fail (mutex != NULL);
g_mutex_init (&mutex->mutex);
g_mutex_init (&mutex->base.cond_mutex);
g_cond_init (&mutex->base.cond);
}
/**
* e_cancellable_mutex_clear:
* @mutex: an #ECancellableMutex instance
*
* Frees memory allocated by e_cancellable_mutex_init().
*
* Since: 3.8
*
* Deprecated: 3.12: If you think you need this, you're using mutexes wrong.
**/
void
e_cancellable_mutex_clear (ECancellableMutex *mutex)
{
g_return_if_fail (mutex != NULL);
g_mutex_clear (&mutex->mutex);
g_mutex_clear (&mutex->base.cond_mutex);
g_cond_clear (&mutex->base.cond);
}
/**
* e_cancellable_mutex_lock:
* @mutex: an #ECancellableMutex instance
* @cancellable: a #GCancellable, or %NULL
*
* Acquires lock on @mutex. The returned value indicates whether
* the lock was acquired, while %FALSE is returned only either or
* invalid arguments or the passed in @cancellable had been cancelled.
* In case of %NULL @cancellable the function blocks like g_mutex_lock().
*
* Returns: %TRUE, if lock had been acquired, %FALSE otherwise
*
* Since: 3.8
*
* Deprecated: 3.12: If you think you need this, you're using mutexes wrong.
**/
gboolean
e_cancellable_mutex_lock (ECancellableMutex *mutex,
GCancellable *cancellable)
{
gulong handler_id;
gboolean res = TRUE;
g_return_val_if_fail (mutex != NULL, FALSE);
g_mutex_lock (&mutex->base.cond_mutex);
if (!cancellable) {
g_mutex_unlock (&mutex->base.cond_mutex);
g_mutex_lock (&mutex->mutex);
return TRUE;
}
if (g_cancellable_is_cancelled (cancellable)) {
g_mutex_unlock (&mutex->base.cond_mutex);
return FALSE;
}
handler_id = g_signal_connect (
cancellable, "cancelled",
G_CALLBACK (cancellable_locks_cancelled_cb), &mutex->base);
while (!g_mutex_trylock (&mutex->mutex)) {
/* recheck once per 10 seconds, just in case */
g_cond_wait_until (
&mutex->base.cond, &mutex->base.cond_mutex,
g_get_monotonic_time () + (10 * G_TIME_SPAN_SECOND));
if (g_cancellable_is_cancelled (cancellable)) {
res = FALSE;
break;
}
}
g_signal_handler_disconnect (cancellable, handler_id);
g_mutex_unlock (&mutex->base.cond_mutex);
return res;
}
/**
* e_cancellable_mutex_unlock:
* @mutex: an #ECancellableMutex instance
*
* Releases lock previously acquired by e_cancellable_mutex_lock().
* Behaviour is undefined if this is called on a @mutex which returned
* %FALSE in e_cancellable_mutex_lock().
*
* Since: 3.8
*
* Deprecated: 3.12: If you think you need this, you're using mutexes wrong.
**/
void
e_cancellable_mutex_unlock (ECancellableMutex *mutex)
{
g_return_if_fail (mutex != NULL);
g_mutex_unlock (&mutex->mutex);
g_mutex_lock (&mutex->base.cond_mutex);
/* also wake-up any waiting threads */
g_cond_broadcast (&mutex->base.cond);
g_mutex_unlock (&mutex->base.cond_mutex);
}
/**
* e_cancellable_mutex_get_internal_mutex:
* @mutex: an #ECancellableMutex instance
*
* To get internal #GMutex. This is meant for cases when a lock is already
* acquired, and the caller needs to wait for a #GCond, in which case
* the returned #GMutex can be used to g_cond_wait() or g_cond_wait_until().
*
* Returns: Internal #GMutex, used in @mutex
*
* Since: 3.8
*
* Deprecated: 3.12: If you think you need this, you're using mutexes wrong.
**/
GMutex *
e_cancellable_mutex_get_internal_mutex (ECancellableMutex *mutex)
{
g_return_val_if_fail (mutex != NULL, NULL);
return &mutex->mutex;
}
/**
* e_cancellable_rec_mutex_init:
* @rec_mutex: an #ECancellableRecMutex instance
*
* Initializes @rec_mutex structure.
*
* Since: 3.8
*
* Deprecated: 3.12: If you think you need this, you're using mutexes wrong.
**/
void
e_cancellable_rec_mutex_init (ECancellableRecMutex *rec_mutex)
{
g_return_if_fail (rec_mutex != NULL);
g_rec_mutex_init (&rec_mutex->rec_mutex);
g_mutex_init (&rec_mutex->base.cond_mutex);
g_cond_init (&rec_mutex->base.cond);
}
/**
* e_cancellable_rec_mutex_clear:
* @rec_mutex: an #ECancellableRecMutex instance
*
* Frees memory allocated by e_cancellable_rec_mutex_init().
*
* Since: 3.8
*
* Deprecated: 3.12: If you think you need this, you're using mutexes wrong.
**/
void
e_cancellable_rec_mutex_clear (ECancellableRecMutex *rec_mutex)
{
g_return_if_fail (rec_mutex != NULL);
g_rec_mutex_clear (&rec_mutex->rec_mutex);
g_mutex_clear (&rec_mutex->base.cond_mutex);
g_cond_clear (&rec_mutex->base.cond);
}
/**
* e_cancellable_rec_mutex_lock:
* @rec_mutex: an #ECancellableRecMutex instance
* @cancellable: a #GCancellable, or %NULL
*
* Acquires lock on @rec_mutex. The returned value indicates whether
* the lock was acquired, while %FALSE is returned only either or
* invalid arguments or the passed in @cancellable had been cancelled.
* In case of %NULL @cancellable the function blocks like g_rec_mutex_lock().
*
* Returns: %TRUE, if lock had been acquired, %FALSE otherwise
*
* Since: 3.8
*
* Deprecated: 3.12: If you think you need this, you're using mutexes wrong.
**/
gboolean
e_cancellable_rec_mutex_lock (ECancellableRecMutex *rec_mutex,
GCancellable *cancellable)
{
gulong handler_id;
gboolean res = TRUE;
g_return_val_if_fail (rec_mutex != NULL, FALSE);
g_mutex_lock (&rec_mutex->base.cond_mutex);
if (!cancellable) {
g_mutex_unlock (&rec_mutex->base.cond_mutex);
g_rec_mutex_lock (&rec_mutex->rec_mutex);
return TRUE;
}
if (g_cancellable_is_cancelled (cancellable)) {
g_mutex_unlock (&rec_mutex->base.cond_mutex);
return FALSE;
}
handler_id = g_signal_connect (
cancellable, "cancelled",
G_CALLBACK (cancellable_locks_cancelled_cb), &rec_mutex->base);
while (!g_rec_mutex_trylock (&rec_mutex->rec_mutex)) {
/* recheck once per 10 seconds, just in case */
g_cond_wait_until (
&rec_mutex->base.cond, &rec_mutex->base.cond_mutex,
g_get_monotonic_time () + (10 * G_TIME_SPAN_SECOND));
if (g_cancellable_is_cancelled (cancellable)) {
res = FALSE;
break;
}
}
g_signal_handler_disconnect (cancellable, handler_id);
g_mutex_unlock (&rec_mutex->base.cond_mutex);
return res;
}
/**
* e_cancellable_rec_mutex_unlock:
* @rec_mutex: an #ECancellableRecMutex instance
*
* Releases lock previously acquired by e_cancellable_rec_mutex_lock().
* Behaviour is undefined if this is called on a @rec_mutex which returned
* %FALSE in e_cancellable_rec_mutex_lock().
*
* Since: 3.8
*
* Deprecated: 3.12: If you think you need this, you're using mutexes wrong.
**/
void
e_cancellable_rec_mutex_unlock (ECancellableRecMutex *rec_mutex)
{
g_return_if_fail (rec_mutex != NULL);
g_rec_mutex_unlock (&rec_mutex->rec_mutex);
g_mutex_lock (&rec_mutex->base.cond_mutex);
/* also wake-up any waiting threads */
g_cond_broadcast (&rec_mutex->base.cond);
g_mutex_unlock (&rec_mutex->base.cond_mutex);
}