2 * Copyright (c) 2016, Alliance for Open Media. All rights reserved
4 * This source code is subject to the terms of the BSD 2 Clause License and
5 * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
6 * was not distributed with this source code in the LICENSE file, you can
7 * obtain it at www.aomedia.org/license/software. If the Alliance for Open
8 * Media Patent License 1.0 was not distributed with this source code in the
9 * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
12 // Multi-threaded worker
15 // https://chromium.googlesource.com/webm/libwebp
17 #ifndef AOM_AOM_UTIL_AOM_THREAD_H_
18 #define AOM_AOM_UTIL_AOM_THREAD_H_
24 // State of the worker thread object
26 AVX_WORKER_STATUS_NOT_OK
= 0, // object is unusable
27 AVX_WORKER_STATUS_OK
, // ready to work
28 AVX_WORKER_STATUS_WORKING
// busy finishing the current task
31 // Function to be called by the worker thread. Takes two opaque pointers as
32 // arguments (data1 and data2). Should return true on success and return false
34 typedef int (*AVxWorkerHook
)(void *, void *);
36 // Platform-dependent implementation details for the worker.
37 typedef struct AVxWorkerImpl AVxWorkerImpl
;
39 // Synchronization object used to launch job in the worker thread
42 AVxWorkerStatus status_
;
43 // Thread name for the debugger. If not NULL, must point to a string that
44 // outlives the worker thread. For portability, use a name <= 15 characters
45 // long (not including the terminating NUL character).
46 const char *thread_name
;
47 AVxWorkerHook hook
; // hook to call
48 void *data1
; // first argument passed to 'hook'
49 void *data2
; // second argument passed to 'hook'
50 int had_error
; // true if a call to 'hook' returned false
53 // The interface for all thread-worker related functions. All these functions
54 // must be implemented.
56 // Must be called first, before any other method.
57 void (*init
)(AVxWorker
*const worker
);
58 // Must be called to initialize the object and spawn the thread. Re-entrant.
59 // Will potentially launch the thread. Returns false in case of error.
60 int (*reset
)(AVxWorker
*const worker
);
61 // Makes sure the previous work is finished. Returns true if worker->had_error
62 // was not set and no error condition was triggered by the working thread.
63 int (*sync
)(AVxWorker
*const worker
);
64 // Triggers the thread to call hook() with data1 and data2 arguments. These
65 // hook/data1/data2 values can be changed at any time before calling this
66 // function, but not be changed afterward until the next call to Sync().
67 void (*launch
)(AVxWorker
*const worker
);
68 // This function is similar to launch() except that it calls the
69 // hook directly instead of using a thread. Convenient to bypass the thread
70 // mechanism while still using the AVxWorker structs. sync() must
71 // still be called afterward (for error reporting).
72 void (*execute
)(AVxWorker
*const worker
);
73 // Kill the thread and terminate the object. To use the object again, one
74 // must call reset() again.
75 void (*end
)(AVxWorker
*const worker
);
78 // Install a new set of threading functions, overriding the defaults. This
79 // should be done before any workers are started, i.e., before any encoding or
80 // decoding takes place. The contents of the interface struct are copied, it
81 // is safe to free the corresponding memory after this call. This function is
82 // not thread-safe. Return false in case of invalid pointer or methods.
83 int aom_set_worker_interface(const AVxWorkerInterface
*const winterface
);
85 // Retrieve the currently set thread worker interface.
86 const AVxWorkerInterface
*aom_get_worker_interface(void);
88 //------------------------------------------------------------------------------
94 #endif // AOM_AOM_UTIL_AOM_THREAD_H_