1 // Copyright 2013 Google Inc. All Rights Reserved. 2 // 3 // Use of this source code is governed by a BSD-style license 4 // that can be found in the COPYING file in the root of the source 5 // tree. An additional intellectual property rights grant can be found 6 // in the file PATENTS. All contributing project authors may 7 // be found in the AUTHORS file in the root of the source tree. 8 // ----------------------------------------------------------------------------- 9 // 10 // Multi-threaded worker 11 // 12 // Original source: 13 // http://git.chromium.org/webm/libwebp.git 14 // 100644 blob 13a61a4c84194c3374080cbf03d881d3cd6af40d src/utils/thread.h 15 16 17 #ifndef VP9_DECODER_VP9_THREAD_H_ 18 #define VP9_DECODER_VP9_THREAD_H_ 19 20 #include "./vpx_config.h" 21 22 #if defined(__cplusplus) || defined(c_plusplus) 23 extern "C" { 24 #endif 25 26 #if CONFIG_MULTITHREAD 27 28 #if defined(_WIN32) 29 30 #include <windows.h> // NOLINT 31 typedef HANDLE pthread_t; 32 typedef CRITICAL_SECTION pthread_mutex_t; 33 typedef struct { 34 HANDLE waiting_sem_; 35 HANDLE received_sem_; 36 HANDLE signal_event_; 37 } pthread_cond_t; 38 39 #else 40 41 #include <pthread.h> // NOLINT 42 43 #endif /* _WIN32 */ 44 #endif /* CONFIG_MULTITHREAD */ 45 46 // State of the worker thread object 47 typedef enum { 48 NOT_OK = 0, // object is unusable 49 OK, // ready to work 50 WORK // busy finishing the current task 51 } VP9WorkerStatus; 52 53 // Function to be called by the worker thread. Takes two opaque pointers as 54 // arguments (data1 and data2), and should return false in case of error. 55 typedef int (*VP9WorkerHook)(void*, void*); 56 57 // Synchronize object used to launch job in the worker thread 58 typedef struct { 59 #if CONFIG_MULTITHREAD 60 pthread_mutex_t mutex_; 61 pthread_cond_t condition_; 62 pthread_t thread_; 63 #endif 64 VP9WorkerStatus status_; 65 VP9WorkerHook hook; // hook to call 66 void* data1; // first argument passed to 'hook' 67 void* data2; // second argument passed to 'hook' 68 int had_error; // return value of the last call to 'hook' 69 } VP9Worker; 70 71 // Must be called first, before any other method. 72 void vp9_worker_init(VP9Worker* const worker); 73 // Must be called to initialize the object and spawn the thread. Re-entrant. 74 // Will potentially launch the thread. Returns false in case of error. 75 int vp9_worker_reset(VP9Worker* const worker); 76 // Makes sure the previous work is finished. Returns true if worker->had_error 77 // was not set and no error condition was triggered by the working thread. 78 int vp9_worker_sync(VP9Worker* const worker); 79 // Triggers the thread to call hook() with data1 and data2 argument. These 80 // hook/data1/data2 can be changed at any time before calling this function, 81 // but not be changed afterward until the next call to vp9_worker_sync(). 82 void vp9_worker_launch(VP9Worker* const worker); 83 // This function is similar to vp9_worker_launch() except that it calls the 84 // hook directly instead of using a thread. Convenient to bypass the thread 85 // mechanism while still using the VP9Worker structs. vp9_worker_sync() must 86 // still be called afterward (for error reporting). 87 void vp9_worker_execute(VP9Worker* const worker); 88 // Kill the thread and terminate the object. To use the object again, one 89 // must call vp9_worker_reset() again. 90 void vp9_worker_end(VP9Worker* const worker); 91 92 //------------------------------------------------------------------------------ 93 94 #if defined(__cplusplus) || defined(c_plusplus) 95 } // extern "C" 96 #endif 97 98 #endif // VP9_DECODER_VP9_THREAD_H_ 99
