/* * Copyright (c) 2016, Alliance for Open Media. All rights reserved * * This source code is subject to the terms of the BSD 2 Clause License and * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License * was not distributed with this source code in the LICENSE file, you can * obtain it at www.aomedia.org/license/software. If the Alliance for Open * Media Patent License 1.0 was not distributed with this source code in the * PATENTS file, you can obtain it at www.aomedia.org/license/patent. */ // // Multi-threaded worker // // Original source: // https://chromium.googlesource.com/webm/libwebp #ifndef AOM_AOM_UTIL_AOM_THREAD_H_ #define AOM_AOM_UTIL_AOM_THREAD_H_ #ifdef __cplusplus extern "C" { #endif // State of the worker thread object typedef enum { AVX_WORKER_STATUS_NOT_OK = 0, // object is unusable AVX_WORKER_STATUS_OK, // ready to work AVX_WORKER_STATUS_WORKING // busy finishing the current task } AVxWorkerStatus; // Function to be called by the worker thread. Takes two opaque pointers as // arguments (data1 and data2). Should return true on success and return false // in case of error. typedef int (*AVxWorkerHook)(void *, void *); // Platform-dependent implementation details for the worker. typedef struct AVxWorkerImpl AVxWorkerImpl; // Synchronization object used to launch job in the worker thread typedef struct { AVxWorkerImpl *impl_; AVxWorkerStatus status_; // Thread name for the debugger. If not NULL, must point to a string that // outlives the worker thread. For portability, use a name <= 15 characters // long (not including the terminating NUL character). const char *thread_name; AVxWorkerHook hook; // hook to call void *data1; // first argument passed to 'hook' void *data2; // second argument passed to 'hook' int had_error; // true if a call to 'hook' returned false } AVxWorker; // The interface for all thread-worker related functions. All these functions // must be implemented. typedef struct { // Must be called first, before any other method. void (*init)(AVxWorker *const worker); // Must be called to initialize the object and spawn the thread. Re-entrant. // Will potentially launch the thread. Returns false in case of error. int (*reset)(AVxWorker *const worker); // Makes sure the previous work is finished. Returns true if worker->had_error // was not set and no error condition was triggered by the working thread. int (*sync)(AVxWorker *const worker); // Triggers the thread to call hook() with data1 and data2 arguments. These // hook/data1/data2 values can be changed at any time before calling this // function, but not be changed afterward until the next call to Sync(). void (*launch)(AVxWorker *const worker); // This function is similar to launch() except that it calls the // hook directly instead of using a thread. Convenient to bypass the thread // mechanism while still using the AVxWorker structs. sync() must // still be called afterward (for error reporting). void (*execute)(AVxWorker *const worker); // Kill the thread and terminate the object. To use the object again, one // must call reset() again. void (*end)(AVxWorker *const worker); } AVxWorkerInterface; // Install a new set of threading functions, overriding the defaults. This // should be done before any workers are started, i.e., before any encoding or // decoding takes place. The contents of the interface struct are copied, it // is safe to free the corresponding memory after this call. This function is // not thread-safe. Return false in case of invalid pointer or methods. int aom_set_worker_interface(const AVxWorkerInterface *const winterface); // Retrieve the currently set thread worker interface. const AVxWorkerInterface *aom_get_worker_interface(void); //------------------------------------------------------------------------------ #ifdef __cplusplus } // extern "C" #endif #endif // AOM_AOM_UTIL_AOM_THREAD_H_