Security-57031.20.26.tar.gz

[apple/security.git] / Security / libsecurity_utilities / lib / dispatch.h

diff --git a/Security/libsecurity_utilities/lib/dispatch.h b/Security/libsecurity_utilities/lib/dispatch.h
new file mode 100644 (file)
index 0000000..558e5f0
--- /dev/null
+++ b/Security/libsecurity_utilities/lib/dispatch.h
@@ -0,0 +1,126 @@
+/*
+ * Copyright (c) 2014 Apple Inc. All Rights Reserved.
+ * 
+ * @APPLE_LICENSE_HEADER_START@
+ * 
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ * 
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ * 
+ * @APPLE_LICENSE_HEADER_END@
+ */
+
+//
+// dispatch - libdispatch wrapper
+//
+#ifndef _H_DISPATCH
+#define _H_DISPATCH
+
+#include <dispatch/dispatch.h>
+#include <security_utilities/utilities.h>
+#include <security_utilities/threading.h>
+
+#include <exception>
+
+namespace Security {
+namespace Dispatch {
+
+
+// Wraps dispatch objects which can be used to queue blocks, i.e. dispatch groups and queues.
+// If a block throws an exception, no further blocks are enqueued and the exception is rethrown
+// after waiting for completion of all blocks.
+class ExceptionAwareEnqueuing {
+       NOCOPY(ExceptionAwareEnqueuing)
+public:
+       ExceptionAwareEnqueuing();
+
+       void enqueueWithDispatcher(void (^dispatcher)(dispatch_block_t), dispatch_block_t block);
+       void throwPendingException();
+private:
+       Mutex mLock;
+       bool mExceptionPending;
+       std::exception_ptr mException;
+};
+
+
+class Queue {
+       NOCOPY(Queue)
+public:
+       Queue(const char *label, bool concurrent, dispatch_qos_class_t qos_class = QOS_CLASS_DEFAULT);
+       virtual ~Queue();
+
+       operator dispatch_queue_t () const { return mQueue; }
+
+       void enqueue(dispatch_block_t block);
+       void wait();
+
+private:
+       ExceptionAwareEnqueuing enqueuing;
+       dispatch_queue_t mQueue;
+};
+
+
+class Group {
+       NOCOPY(Group)
+public:
+       Group();
+       virtual ~Group();
+
+       operator dispatch_group_t () const { return mGroup; }
+
+       void enqueue(dispatch_queue_t queue, dispatch_block_t block);
+       void wait();
+
+private:
+       ExceptionAwareEnqueuing enqueuing;
+       dispatch_group_t mGroup;
+};
+
+
+class Semaphore {
+       NOCOPY(Semaphore)
+public:
+       Semaphore(long count);
+       Semaphore(Semaphore& semaphore);
+       virtual ~Semaphore();
+
+       operator dispatch_semaphore_t () const { return mSemaphore; };
+
+       bool signal();
+       bool wait(dispatch_time_t timeout = DISPATCH_TIME_FOREVER);
+
+private:
+       dispatch_semaphore_t mSemaphore;
+};
+
+
+class SemaphoreWait {
+       NOCOPY(SemaphoreWait)
+public:
+       SemaphoreWait(SemaphoreWait& originalWait);
+       SemaphoreWait(Semaphore& semaphore, dispatch_time_t timeout = DISPATCH_TIME_FOREVER);
+       virtual ~SemaphoreWait();
+
+       bool acquired() const { return mAcquired; };
+
+private:
+       Semaphore &mSemaphore;
+       bool mAcquired;
+};
+
+
+} // end namespace Dispatch
+} // end namespace Security
+
+#endif // !_H_DISPATCH