Merge pull request 'SharedRingBuffer' (#167) from KSat/fsfw:mueller/sharedRingBufferPullRequest into master

Reviewed-on: fsfw/fsfw#167

container/SharedRingBuffer.cpp

@@ -0,0 +1,30 @@
+#include "SharedRingBuffer.h"
+#include "../ipc/MutexFactory.h"
+#include "../ipc/MutexHelper.h"
+
+SharedRingBuffer::SharedRingBuffer(object_id_t objectId, const size_t size,
+		bool overwriteOld, size_t maxExcessBytes):
+		SystemObject(objectId), SimpleRingBuffer(size, overwriteOld,
+		maxExcessBytes) {
+	mutex = MutexFactory::instance()->createMutex();
+}
+
+SharedRingBuffer::SharedRingBuffer(object_id_t objectId, uint8_t *buffer,
+		const size_t size, bool overwriteOld, size_t maxExcessBytes):
+		SystemObject(objectId), SimpleRingBuffer(buffer, size, overwriteOld,
+		maxExcessBytes) {
+	mutex = MutexFactory::instance()->createMutex();
+}
+
+ReturnValue_t SharedRingBuffer::lockRingBufferMutex(
+        MutexIF::TimeoutType timeoutType, dur_millis_t timeout) {
+    return mutex->lockMutex(timeoutType, timeout);
+}
+
+ReturnValue_t SharedRingBuffer::unlockRingBufferMutex() {
+    return mutex->unlockMutex();
+}
+
+MutexIF* SharedRingBuffer::getMutexHandle() const {
+    return mutex;
+}

container/SharedRingBuffer.h

@@ -0,0 +1,68 @@
+#ifndef FSFW_CONTAINER_SHAREDRINGBUFFER_H_
+#define FSFW_CONTAINER_SHAREDRINGBUFFER_H_
+
+#include "SimpleRingBuffer.h"
+#include "../ipc/MutexIF.h"
+#include "../objectmanager/SystemObject.h"
+#include "../timemanager/Clock.h"
+
+/**
+ * @brief   Ring buffer which can be shared among multiple objects
+ * @details
+ * This class offers a mutex to perform thread-safe operation on the ring
+ * buffer. It is still up to the developer to actually perform the lock
+ * and unlock operations.
+ */
+class SharedRingBuffer: public SystemObject,
+		public SimpleRingBuffer {
+public:
+	/**
+	 * This constructor allocates a new internal buffer with the supplied size.
+	 * @param size
+	 * @param overwriteOld
+	 * If the ring buffer is overflowing at a write operartion, the oldest data
+	 * will be overwritten.
+	 */
+	SharedRingBuffer(object_id_t objectId, const size_t size,
+			bool overwriteOld, size_t maxExcessBytes);
+
+	/**
+	 * This constructor takes an external buffer with the specified size.
+	 * @param buffer
+	 * @param size
+	 * @param overwriteOld
+	 * If the ring buffer is overflowing at a write operartion, the oldest data
+	 * will be overwritten.
+	 */
+	SharedRingBuffer(object_id_t objectId, uint8_t* buffer, const size_t size,
+			bool overwriteOld, size_t maxExcessBytes);
+
+	/**
+	 * Unless a read-only constant value is read, all operations on the
+	 * shared ring buffer should be protected by calling this function.
+	 * @param timeoutType
+	 * @param timeout
+	 * @return
+	 */
+	virtual ReturnValue_t lockRingBufferMutex(MutexIF::TimeoutType timeoutType,
+	        dur_millis_t timeout);
+	/**
+	 * Any locked mutex also has to be unlocked, otherwise, access to the
+	 * shared ring buffer will be blocked.
+	 * @return
+	 */
+	virtual ReturnValue_t unlockRingBufferMutex();
+
+	/**
+	 * The mutex handle can be accessed directly, for example to perform
+	 * the lock with the #MutexHelper for a RAII compliant lock operation.
+	 * @return
+	 */
+	MutexIF* getMutexHandle() const;
+private:
+	MutexIF* mutex = nullptr;
+};
+
+
+
+#endif /* FSFW_CONTAINER_SHAREDRINGBUFFER_H_ */