michael@0: // Copyright 2013 Google Inc. All Rights Reserved.
michael@0: //
michael@0: // Use of this source code is governed by a BSD-style license
michael@0: // that can be found in the COPYING file in the root of the source
michael@0: // tree. An additional intellectual property rights grant can be found
michael@0: // in the file PATENTS. All contributing project authors may
michael@0: // be found in the AUTHORS file in the root of the source tree.
michael@0: // -----------------------------------------------------------------------------
michael@0: //
michael@0: // Multi-threaded worker
michael@0: //
michael@0: // Original source:
michael@0: //  http://git.chromium.org/webm/libwebp.git
michael@0: //  100644 blob 13a61a4c84194c3374080cbf03d881d3cd6af40d  src/utils/thread.h
michael@0: 
michael@0: 
michael@0: #ifndef VP9_DECODER_VP9_THREAD_H_
michael@0: #define VP9_DECODER_VP9_THREAD_H_
michael@0: 
michael@0: #include "./vpx_config.h"
michael@0: 
michael@0: #if defined(__cplusplus) || defined(c_plusplus)
michael@0: extern "C" {
michael@0: #endif
michael@0: 
michael@0: #if CONFIG_MULTITHREAD
michael@0: 
michael@0: #if defined(_WIN32)
michael@0: 
michael@0: #include <windows.h>  // NOLINT
michael@0: typedef HANDLE pthread_t;
michael@0: typedef CRITICAL_SECTION pthread_mutex_t;
michael@0: typedef struct {
michael@0:   HANDLE waiting_sem_;
michael@0:   HANDLE received_sem_;
michael@0:   HANDLE signal_event_;
michael@0: } pthread_cond_t;
michael@0: 
michael@0: #else
michael@0: 
michael@0: #include <pthread.h> // NOLINT
michael@0: 
michael@0: #endif    /* _WIN32 */
michael@0: #endif    /* CONFIG_MULTITHREAD */
michael@0: 
michael@0: // State of the worker thread object
michael@0: typedef enum {
michael@0:   NOT_OK = 0,   // object is unusable
michael@0:   OK,           // ready to work
michael@0:   WORK          // busy finishing the current task
michael@0: } VP9WorkerStatus;
michael@0: 
michael@0: // Function to be called by the worker thread. Takes two opaque pointers as
michael@0: // arguments (data1 and data2), and should return false in case of error.
michael@0: typedef int (*VP9WorkerHook)(void*, void*);
michael@0: 
michael@0: // Synchronize object used to launch job in the worker thread
michael@0: typedef struct {
michael@0: #if CONFIG_MULTITHREAD
michael@0:   pthread_mutex_t mutex_;
michael@0:   pthread_cond_t  condition_;
michael@0:   pthread_t       thread_;
michael@0: #endif
michael@0:   VP9WorkerStatus status_;
michael@0:   VP9WorkerHook hook;     // hook to call
michael@0:   void* data1;            // first argument passed to 'hook'
michael@0:   void* data2;            // second argument passed to 'hook'
michael@0:   int had_error;          // return value of the last call to 'hook'
michael@0: } VP9Worker;
michael@0: 
michael@0: // Must be called first, before any other method.
michael@0: void vp9_worker_init(VP9Worker* const worker);
michael@0: // Must be called to initialize the object and spawn the thread. Re-entrant.
michael@0: // Will potentially launch the thread. Returns false in case of error.
michael@0: int vp9_worker_reset(VP9Worker* const worker);
michael@0: // Makes sure the previous work is finished. Returns true if worker->had_error
michael@0: // was not set and no error condition was triggered by the working thread.
michael@0: int vp9_worker_sync(VP9Worker* const worker);
michael@0: // Triggers the thread to call hook() with data1 and data2 argument. These
michael@0: // hook/data1/data2 can be changed at any time before calling this function,
michael@0: // but not be changed afterward until the next call to vp9_worker_sync().
michael@0: void vp9_worker_launch(VP9Worker* const worker);
michael@0: // This function is similar to vp9_worker_launch() except that it calls the
michael@0: // hook directly instead of using a thread. Convenient to bypass the thread
michael@0: // mechanism while still using the VP9Worker structs. vp9_worker_sync() must
michael@0: // still be called afterward (for error reporting).
michael@0: void vp9_worker_execute(VP9Worker* const worker);
michael@0: // Kill the thread and terminate the object. To use the object again, one
michael@0: // must call vp9_worker_reset() again.
michael@0: void vp9_worker_end(VP9Worker* const worker);
michael@0: 
michael@0: //------------------------------------------------------------------------------
michael@0: 
michael@0: #if defined(__cplusplus) || defined(c_plusplus)
michael@0: }    // extern "C"
michael@0: #endif
michael@0: 
michael@0: #endif  // VP9_DECODER_VP9_THREAD_H_