Added a simple blocking queue around linked_list_t

4 files changed, 232 insertions, 6 deletions

diff --git a/src/libstrongswan/Android.mk b/src/libstrongswan/Android.mk
index b6abf156f..398e371e8 100644
--- a/src/libstrongswan/Android.mk
+++ b/src/libstrongswan/Android.mk
@@ -25,8 +25,8 @@ processing/jobs/callback_job.c processing/processor.c processing/scheduler.c \
 selectors/traffic_selector.c threading/thread.c threading/thread_value.c \
 threading/mutex.c threading/semaphore.c threading/rwlock.c threading/spinlock.c \
 utils.c utils/host.c utils/packet.c utils/identification.c utils/lexparser.c \
-utils/linked_list.c utils/hashtable.c utils/enumerator.c utils/optionsfrom.c \
-utils/capabilities.c utils/backtrace.c
+utils/linked_list.c utils/blocking_queue.c utils/hashtable.c utils/enumerator.c \
+utils/optionsfrom.c utils/capabilities.c utils/backtrace.c
 
 # adding the plugin source files
 
diff --git a/src/libstrongswan/Makefile.am b/src/libstrongswan/Makefile.am
index b21f86f1e..383efc8b8 100644
--- a/src/libstrongswan/Makefile.am
+++ b/src/libstrongswan/Makefile.am
@@ -23,8 +23,8 @@ processing/jobs/callback_job.c processing/processor.c processing/scheduler.c \
 selectors/traffic_selector.c threading/thread.c threading/thread_value.c \
 threading/mutex.c threading/semaphore.c threading/rwlock.c threading/spinlock.c \
 utils.c utils/host.c utils/packet.c utils/identification.c utils/lexparser.c \
-utils/linked_list.c utils/hashtable.c utils/enumerator.c utils/optionsfrom.c \
-utils/capabilities.c utils/backtrace.c
+utils/linked_list.c utils/blocking_queue.c utils/hashtable.c utils/enumerator.c \
+utils/optionsfrom.c utils/capabilities.c utils/backtrace.c
 
 if USE_DEV_HEADERS
 strongswan_includedir = ${dev_headers}
@@ -58,8 +58,8 @@ selectors/traffic_selector.h threading/thread.h threading/thread_value.h \
 threading/mutex.h threading/condvar.h threading/spinlock.h threading/semaphore.h \
 threading/rwlock.h threading/lock_profiler.h utils.h utils/host.h \
 utils/packet.h utils/identification.h utils/lexparser.h utils/linked_list.h \
-utils/hashtable.h utils/enumerator.h utils/optionsfrom.h utils/capabilities.h \
-utils/backtrace.h
+utils/blocking_queue.h utils/hashtable.h utils/enumerator.h utils/optionsfrom.h \
+utils/capabilities.h utils/backtrace.h
 endif
 
 library.lo :	$(top_builddir)/config.status
diff --git a/src/libstrongswan/utils/blocking_queue.c b/src/libstrongswan/utils/blocking_queue.c
new file mode 100644
index 000000000..c70184198
--- /dev/null
+++ b/src/libstrongswan/utils/blocking_queue.c
@@ -0,0 +1,129 @@
+/*
+ * Copyright (C) 2012 Tobias Brunner
+ * Copyright (C) 2012 Giuliano Grassi
+ * Copyright (C) 2012 Ralf Sager
+ * Hochschule fuer Technik Rapperswil
+ *
+ * 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.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * 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.
+ */
+
+#include "blocking_queue.h"
+
+#include <threading/mutex.h>
+#include <threading/thread.h>
+#include <threading/condvar.h>
+#include <utils/linked_list.h>
+
+typedef struct private_blocking_queue_t private_blocking_queue_t;
+
+/**
+ * Private data of a blocking_queue_t object.
+ */
+struct private_blocking_queue_t {
+
+	/**
+	 * Public part
+	 */
+	blocking_queue_t public;
+
+	/**
+	 * Linked list containing all items in the queue
+	 */
+	linked_list_t *list;
+
+	/**
+	 * Mutex used to synchronize access to the queue
+	 */
+	mutex_t *mutex;
+
+	/**
+	 * Condvar used to wait for items
+	 */
+	condvar_t *condvar;
+
+};
+
+METHOD(blocking_queue_t, enqueue, void,
+	private_blocking_queue_t *this, void *item)
+{
+	this->mutex->lock(this->mutex);
+	this->list->insert_first(this->list, item);
+	this->condvar->signal(this->condvar);
+	this->mutex->unlock(this->mutex);
+}
+
+METHOD(blocking_queue_t, dequeue, void*,
+	private_blocking_queue_t *this)
+{
+	bool oldstate;
+	void *item;
+
+
+	this->mutex->lock(this->mutex);
+	thread_cleanup_push((thread_cleanup_t)this->mutex->unlock, this->mutex);
+	/* ensure that a canceled thread does not dequeue any items */
+	thread_cancellation_point();
+	while (this->list->remove_last(this->list, &item) != SUCCESS)
+	{
+		oldstate = thread_cancelability(TRUE);
+		this->condvar->wait(this->condvar, this->mutex);
+		thread_cancelability(oldstate);
+	}
+	thread_cleanup_pop(TRUE);
+	return item;
+}
+
+METHOD(blocking_queue_t, destroy, void,
+	private_blocking_queue_t *this)
+{
+	this->list->destroy(this->list);
+	this->condvar->destroy(this->condvar);
+	this->mutex->destroy(this->mutex);
+	free(this);
+}
+
+METHOD(blocking_queue_t, destroy_offset, void,
+	private_blocking_queue_t *this, size_t offset)
+{
+	this->list->invoke_offset(this->list, offset);
+	destroy(this);
+}
+
+METHOD(blocking_queue_t, destroy_function, void,
+	private_blocking_queue_t *this, void (*fn)(void*))
+{
+	this->list->invoke_function(this->list, (linked_list_invoke_t)fn);
+	destroy(this);
+}
+
+/*
+ * Described in header.
+ */
+blocking_queue_t *blocking_queue_create()
+{
+	private_blocking_queue_t *this;
+
+	INIT(this,
+		.public = {
+			.enqueue = _enqueue,
+			.dequeue = _dequeue,
+			.destroy = _destroy,
+			.destroy_offset = _destroy_offset,
+			.destroy_function = _destroy_function,
+		},
+		.list = linked_list_create(),
+		.mutex = mutex_create(MUTEX_TYPE_DEFAULT),
+		.condvar = condvar_create(CONDVAR_TYPE_DEFAULT),
+	);
+
+	return &this->public;
+}
+
diff --git a/src/libstrongswan/utils/blocking_queue.h b/src/libstrongswan/utils/blocking_queue.h
new file mode 100644
index 000000000..cf2712cf4
--- /dev/null
+++ b/src/libstrongswan/utils/blocking_queue.h
@@ -0,0 +1,97 @@
+/*
+ * Copyright (C) 2012 Tobias Brunner
+ * Copyright (C) 2012 Giuliano Grassi
+ * Copyright (C) 2012 Ralf Sager
+ * Hochschule fuer Technik Rapperswil
+ *
+ * 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.  See <http://www.fsf.org/copyleft/gpl.txt>.
+ *
+ * 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.
+ */
+
+/**
+ * @defgroup blocking_queue blocking_queue
+ * @{ @ingroup utils
+ */
+
+#ifndef BLOCKING_QUEUE_H_
+#define BLOCKING_QUEUE_H_
+
+typedef struct blocking_queue_t blocking_queue_t;
+
+#include <library.h>
+
+/**
+ * Class implementing a synchronized blocking queue based on linked_list_t
+ */
+struct blocking_queue_t {
+
+	/**
+	 * Inserts a new item at the tail of the queue
+	 *
+	 * @param item		item to insert in queue
+	 */
+	void (*enqueue)(blocking_queue_t *this, void *item);
+
+	/**
+	 * Removes the first item in the queue and returns its value.
+	 * If the queue is empty, this call blocks until a new item is inserted.
+	 *
+	 * @note This is a thread cancellation point
+	 *
+	 * @return			removed item
+	 */
+	void *(*dequeue)(blocking_queue_t *this);
+
+	/**
+	 * Destroys a blocking_queue_t object.
+	 *
+	 * @note No thread must wait in dequeue() when this function is called
+	 */
+	void (*destroy)(blocking_queue_t *this);
+
+	/**
+	 * Destroys a queue and its objects using the given destructor.
+	 *
+	 * If a queue and the contained objects should be destroyed, use
+	 * destroy_offset. The supplied offset specifies the destructor to
+	 * call on each object. The offset may be calculated using the offsetof
+	 * macro, e.g.: queue->destroy_offset(queue, offsetof(object_t, destroy));
+	 *
+	 * @note No thread must wait in dequeue() when this function is called
+	 *
+	 * @param offset	offset of the objects destructor
+	 */
+	void (*destroy_offset)(blocking_queue_t *this, size_t offset);
+
+	/**
+	 * Destroys a queue and its objects using a cleanup function.
+	 *
+	 * If a queue and its contents should get destroyed using a specific
+	 * cleanup function, use destroy_function. This is useful when the
+	 * list contains malloc()-ed blocks which should get freed,
+	 * e.g.: queue->destroy_function(queue, free);
+	 *
+	 * @note No thread must wait in dequeue() when this function is called
+	 *
+	 * @param function	function to call on each object
+	 */
+	void (*destroy_function)(blocking_queue_t *this, void (*)(void*));
+
+};
+
+/**
+ * Creates an empty queue object.
+ *
+ * @return		blocking_queue_t object.
+ */
+blocking_queue_t *blocking_queue_create();
+
+#endif /** BLOCKING_QUEUE_H_ @}*/
+