thread.h revision 1e7bf8805bd030c19924a5306837ecd72c295751
1a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Copyright 2011 Google Inc. All Rights Reserved. 2a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// 3a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// This code is licensed under the same terms as WebM: 4a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Software License Agreement: http://www.webmproject.org/license/software/ 5a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Additional IP Rights Grant: http://www.webmproject.org/license/additional/ 6a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// ----------------------------------------------------------------------------- 7a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// 8a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Multi-threaded worker 9a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// 10a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Author: Skal (pascal.massimino@gmail.com) 11a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 12a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora#ifndef WEBP_UTILS_THREAD_H_ 13a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora#define WEBP_UTILS_THREAD_H_ 14a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 151e7bf8805bd030c19924a5306837ecd72c295751Vikas Arora#ifdef HAVE_CONFIG_H 161e7bf8805bd030c19924a5306837ecd72c295751Vikas Arora#include "config.h" 171e7bf8805bd030c19924a5306837ecd72c295751Vikas Arora#endif 181e7bf8805bd030c19924a5306837ecd72c295751Vikas Arora 19a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora#if defined(__cplusplus) || defined(c_plusplus) 20a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Aroraextern "C" { 21a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora#endif 22a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 23a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora#if WEBP_USE_THREAD 24a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 25a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora#if defined(_WIN32) 26a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 27a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora#include <windows.h> 28a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Aroratypedef HANDLE pthread_t; 29a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Aroratypedef CRITICAL_SECTION pthread_mutex_t; 30a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Aroratypedef struct { 31a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora HANDLE waiting_sem_; 32a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora HANDLE received_sem_; 33a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora HANDLE signal_event_; 34a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora} pthread_cond_t; 35a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 36a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora#else 37a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 38a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora#include <pthread.h> 39a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 40a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora#endif /* _WIN32 */ 41a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora#endif /* WEBP_USE_THREAD */ 42a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 43a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// State of the worker thread object 44a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Aroratypedef enum { 45a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora NOT_OK = 0, // object is unusable 46a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora OK, // ready to work 47a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora WORK // busy finishing the current task 48a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora} WebPWorkerStatus; 49a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 50a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Function to be called by the worker thread. Takes two opaque pointers as 51a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// arguments (data1 and data2), and should return false in case of error. 52a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Aroratypedef int (*WebPWorkerHook)(void*, void*); 53a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 54a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Synchronize object used to launch job in the worker thread 55a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Aroratypedef struct { 56a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora#if WEBP_USE_THREAD 57a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora pthread_mutex_t mutex_; 58a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora pthread_cond_t condition_; 59a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora pthread_t thread_; 60a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora#endif 61a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora WebPWorkerStatus status_; 62a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora WebPWorkerHook hook; // hook to call 63a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora void* data1; // first argument passed to 'hook' 64a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora void* data2; // second argument passed to 'hook' 65a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora int had_error; // return value of the last call to 'hook' 66a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora} WebPWorker; 67a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 68a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Must be called first, before any other method. 69a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Aroravoid WebPWorkerInit(WebPWorker* const worker); 701e7bf8805bd030c19924a5306837ecd72c295751Vikas Arora// Must be called to initialize the object and spawn the thread. Re-entrant. 71a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Will potentially launch the thread. Returns false in case of error. 72a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Aroraint WebPWorkerReset(WebPWorker* const worker); 731e7bf8805bd030c19924a5306837ecd72c295751Vikas Arora// Makes sure the previous work is finished. Returns true if worker->had_error 741e7bf8805bd030c19924a5306837ecd72c295751Vikas Arora// was not set and no error condition was triggered by the working thread. 75a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Aroraint WebPWorkerSync(WebPWorker* const worker); 761e7bf8805bd030c19924a5306837ecd72c295751Vikas Arora// Triggers the thread to call hook() with data1 and data2 argument. These 77a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// hook/data1/data2 can be changed at any time before calling this function, 78a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// but not be changed afterward until the next call to WebPWorkerSync(). 79a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Aroravoid WebPWorkerLaunch(WebPWorker* const worker); 80a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// Kill the thread and terminate the object. To use the object again, one 81a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora// must call WebPWorkerReset() again. 82a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Aroravoid WebPWorkerEnd(WebPWorker* const worker); 83a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 84a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora//------------------------------------------------------------------------------ 85a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 86a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora#if defined(__cplusplus) || defined(c_plusplus) 87a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora} // extern "C" 88a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora#endif 89a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora 90a2415724fb3466168b2af5b08bd94ba732c0e753Vikas Arora#endif /* WEBP_UTILS_THREAD_H_ */ 91