From: Shubhanshu Saxena Date: Mon, 26 Apr 2021 07:46:50 +0000 (+0530) Subject: lavfi/dnn/safe_queue.h: Add Documentation to SafeQueue X-Git-Url: https://git.sesse.net/?a=commitdiff_plain;h=5b8e828dee9be4e35973825b7a4a35dacc131557;p=ffmpeg lavfi/dnn/safe_queue.h: Add Documentation to SafeQueue Documentation for SafeQueue Signed-off-by: Shubhanshu Saxena --- diff --git a/libavfilter/dnn/safe_queue.h b/libavfilter/dnn/safe_queue.h index 36d6daabaf4..577a02e24d2 100644 --- a/libavfilter/dnn/safe_queue.h +++ b/libavfilter/dnn/safe_queue.h @@ -21,16 +21,76 @@ #ifndef AVFILTER_DNN_SAFE_QUEUE_H #define AVFILTER_DNN_SAFE_QUEUE_H +/** + * Double-ended queue with mutex locks ensuring + * data consistency while multithreading. + */ typedef struct SafeQueue SafeQueue; +/** + * @brief Create and initialize a SafeQueue instance. + * + * @return Pointer to the SafeQueue + * @retval NULL if initialization fails + */ SafeQueue *ff_safe_queue_create(void); + +/** + * @brief Destroy the SafeQueue instance. + * It also frees all elements of the queue, + * destroys the mutex and condition variable. + */ void ff_safe_queue_destroy(SafeQueue *sq); +/** + * @brief Return the length of the SafeQueue + */ size_t ff_safe_queue_size(SafeQueue *sq); +/** + * @brief Add data to the head of queue in the + * SafeQueue after locking mutex. After adding + * the data, it signals the condition variable + * and unlocks the mutex. It increases the length + * of queue in the SafeQueue by one. + * + * @param sq pointer to the SafeQueue + * @param v data to be added + * @return The length of the queue + * @retval 0 if the queue is not initialized + * @retval -1 if new entry cannot be created + */ int ff_safe_queue_push_front(SafeQueue *sq, void *v); + +/** + * @brief Add data to the tail of queue in the + * SafeQueue after locking mutex. After adding + * the data, it signals the condition variable + * and unlocks the mutex. It increases the length + * of queue in the SafeQueue by one. + * + * @param sq pointer to the SafeQueue + * @param v data to be added + * @return The length of the queue + * @retval 0 if the queue is not initialized + * @retval -1 if new entry cannot be created + */ int ff_safe_queue_push_back(SafeQueue *sq, void *v); +/** + * @brief Remove and free first element from + * the queue in SafeQueue. Before removing, it + * waits for the condition variable to signal and + * acquires the mutex. Finally, it signals the + * condition and unlocks the mutex. + * It shrinks the length of queue in the SafeQueue + * by one. + * + * @param sq pointer to the SafeQueue. + * @return The value of first element as void. + * If a null pointer or empty queue is passed, + * it returns NULL + */ void *ff_safe_queue_pop_front(SafeQueue *sq); #endif