[deb_ffmpeg.git] / ffmpeg / compat / w32pthreads.h

/*
 * Copyright (C) 2010-2011 x264 project
 *
 * Authors: Steven Walters <kemuri9@gmail.com>
 *          Pegasys Inc. <http://www.pegasys-inc.com>
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

/**
 * @file
 * w32threads to pthreads wrapper
 */

#ifndef FFMPEG_COMPAT_W32PTHREADS_H
#define FFMPEG_COMPAT_W32PTHREADS_H

/* Build up a pthread-like API using underlying Windows API. Have only static
 * methods so as to not conflict with a potentially linked in pthread-win32
 * library.
 * As most functions here are used without checking return values,
 * only implement return values as necessary. */

#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include <process.h>

#include "libavutil/attributes.h"
#include "libavutil/common.h"
#include "libavutil/internal.h"
#include "libavutil/mem.h"

typedef struct pthread_t {
    void *handle;
    void *(*func)(void* arg);
    void *arg;
    void *ret;
} pthread_t;

/* the conditional variable api for windows 6.0+ uses critical sections and
 * not mutexes */
typedef CRITICAL_SECTION pthread_mutex_t;

/* This is the CONDITIONAL_VARIABLE typedef for using Window's native
 * conditional variables on kernels 6.0+.
 * MinGW does not currently have this typedef. */
typedef struct pthread_cond_t {
    void *ptr;
} pthread_cond_t;

/* function pointers to conditional variable API on windows 6.0+ kernels */
#if _WIN32_WINNT < 0x0600
static void (WINAPI *cond_broadcast)(pthread_cond_t *cond);
static void (WINAPI *cond_init)(pthread_cond_t *cond);
static void (WINAPI *cond_signal)(pthread_cond_t *cond);
static BOOL (WINAPI *cond_wait)(pthread_cond_t *cond, pthread_mutex_t *mutex,
                                DWORD milliseconds);
#else
#define cond_init      InitializeConditionVariable
#define cond_broadcast WakeAllConditionVariable
#define cond_signal    WakeConditionVariable
#define cond_wait      SleepConditionVariableCS

#define CreateEvent(a, reset, init, name)                   \
    CreateEventEx(a, name,                                  \
                  (reset ? CREATE_EVENT_MANUAL_RESET : 0) | \
                  (init ? CREATE_EVENT_INITIAL_SET : 0),    \
                  EVENT_ALL_ACCESS)
// CreateSemaphoreExA seems to be desktop-only, but as long as we don't
// use named semaphores, it doesn't matter if we use the W version.
#define CreateSemaphore(a, b, c, d) \
    CreateSemaphoreExW(a, b, c, d, 0, SEMAPHORE_ALL_ACCESS)
#define InitializeCriticalSection(x) InitializeCriticalSectionEx(x, 0, 0)
#define WaitForSingleObject(a, b) WaitForSingleObjectEx(a, b, FALSE)
#endif

static av_unused unsigned __stdcall attribute_align_arg win32thread_worker(void *arg)
{
    pthread_t *h = arg;
    h->ret = h->func(h->arg);
    return 0;
}

static av_unused int pthread_create(pthread_t *thread, const void *unused_attr,
                                    void *(*start_routine)(void*), void *arg)
{
    thread->func   = start_routine;
    thread->arg    = arg;
    thread->handle = (void*)_beginthreadex(NULL, 0, win32thread_worker, thread,
                                           0, NULL);
    return !thread->handle;
}

static av_unused void pthread_join(pthread_t thread, void **value_ptr)
{
    DWORD ret = WaitForSingleObject(thread.handle, INFINITE);
    if (ret != WAIT_OBJECT_0)
        return;
    if (value_ptr)
        *value_ptr = thread.ret;
    CloseHandle(thread.handle);
}

static inline int pthread_mutex_init(pthread_mutex_t *m, void* attr)
{
    InitializeCriticalSection(m);
    return 0;
}
static inline int pthread_mutex_destroy(pthread_mutex_t *m)
{
    DeleteCriticalSection(m);
    return 0;
}
static inline int pthread_mutex_lock(pthread_mutex_t *m)
{
    EnterCriticalSection(m);
    return 0;
}
static inline int pthread_mutex_unlock(pthread_mutex_t *m)
{
    LeaveCriticalSection(m);
    return 0;
}

/* for pre-Windows 6.0 platforms we need to define and use our own condition
 * variable and api */
typedef struct  win32_cond_t {
    pthread_mutex_t mtx_broadcast;
    pthread_mutex_t mtx_waiter_count;
    volatile int waiter_count;
    HANDLE semaphore;
    HANDLE waiters_done;
    volatile int is_broadcast;
} win32_cond_t;

static av_unused int pthread_cond_init(pthread_cond_t *cond, const void *unused_attr)
{
    win32_cond_t *win32_cond = NULL;
    if (cond_init) {
        cond_init(cond);
        return 0;
    }

    /* non native condition variables */
    win32_cond = av_mallocz(sizeof(win32_cond_t));
    if (!win32_cond)
        return ENOMEM;
    cond->ptr = win32_cond;
    win32_cond->semaphore = CreateSemaphore(NULL, 0, 0x7fffffff, NULL);
    if (!win32_cond->semaphore)
        return ENOMEM;
    win32_cond->waiters_done = CreateEvent(NULL, TRUE, FALSE, NULL);
    if (!win32_cond->waiters_done)
        return ENOMEM;

    pthread_mutex_init(&win32_cond->mtx_waiter_count, NULL);
    pthread_mutex_init(&win32_cond->mtx_broadcast, NULL);
    return 0;
}

static av_unused void pthread_cond_destroy(pthread_cond_t *cond)
{
    win32_cond_t *win32_cond = cond->ptr;
    /* native condition variables do not destroy */
    if (cond_init)
        return;

    /* non native condition variables */
    CloseHandle(win32_cond->semaphore);
    CloseHandle(win32_cond->waiters_done);
    pthread_mutex_destroy(&win32_cond->mtx_waiter_count);
    pthread_mutex_destroy(&win32_cond->mtx_broadcast);
    av_freep(&win32_cond);
    cond->ptr = NULL;
}

static av_unused void pthread_cond_broadcast(pthread_cond_t *cond)
{
    win32_cond_t *win32_cond = cond->ptr;
    int have_waiter;

    if (cond_broadcast) {
        cond_broadcast(cond);
        return;
    }

    /* non native condition variables */
    pthread_mutex_lock(&win32_cond->mtx_broadcast);
    pthread_mutex_lock(&win32_cond->mtx_waiter_count);
    have_waiter = 0;

    if (win32_cond->waiter_count) {
        win32_cond->is_broadcast = 1;
        have_waiter = 1;
    }

    if (have_waiter) {
        ReleaseSemaphore(win32_cond->semaphore, win32_cond->waiter_count, NULL);
        pthread_mutex_unlock(&win32_cond->mtx_waiter_count);
        WaitForSingleObject(win32_cond->waiters_done, INFINITE);
        ResetEvent(win32_cond->waiters_done);
        win32_cond->is_broadcast = 0;
    } else
        pthread_mutex_unlock(&win32_cond->mtx_waiter_count);
    pthread_mutex_unlock(&win32_cond->mtx_broadcast);
}

static av_unused int pthread_cond_wait(pthread_cond_t *cond, pthread_mutex_t *mutex)
{
    win32_cond_t *win32_cond = cond->ptr;
    int last_waiter;
    if (cond_wait) {
        cond_wait(cond, mutex, INFINITE);
        return 0;
    }

    /* non native condition variables */
    pthread_mutex_lock(&win32_cond->mtx_broadcast);
    pthread_mutex_lock(&win32_cond->mtx_waiter_count);
    win32_cond->waiter_count++;
    pthread_mutex_unlock(&win32_cond->mtx_waiter_count);
    pthread_mutex_unlock(&win32_cond->mtx_broadcast);

    // unlock the external mutex
    pthread_mutex_unlock(mutex);
    WaitForSingleObject(win32_cond->semaphore, INFINITE);

    pthread_mutex_lock(&win32_cond->mtx_waiter_count);
    win32_cond->waiter_count--;
    last_waiter = !win32_cond->waiter_count || !win32_cond->is_broadcast;
    pthread_mutex_unlock(&win32_cond->mtx_waiter_count);

    if (last_waiter)
        SetEvent(win32_cond->waiters_done);

    // lock the external mutex
    return pthread_mutex_lock(mutex);
}

static av_unused void pthread_cond_signal(pthread_cond_t *cond)
{
    win32_cond_t *win32_cond = cond->ptr;
    int have_waiter;
    if (cond_signal) {
        cond_signal(cond);
        return;
    }

    pthread_mutex_lock(&win32_cond->mtx_broadcast);

    /* non-native condition variables */
    pthread_mutex_lock(&win32_cond->mtx_waiter_count);
    have_waiter = win32_cond->waiter_count;
    pthread_mutex_unlock(&win32_cond->mtx_waiter_count);

    if (have_waiter) {
        ReleaseSemaphore(win32_cond->semaphore, 1, NULL);
        WaitForSingleObject(win32_cond->waiters_done, INFINITE);
        ResetEvent(win32_cond->waiters_done);
    }

    pthread_mutex_unlock(&win32_cond->mtx_broadcast);
}

static av_unused void w32thread_init(void)
{
#if _WIN32_WINNT < 0x0600
    HANDLE kernel_dll = GetModuleHandle(TEXT("kernel32.dll"));
    /* if one is available, then they should all be available */
    cond_init      =
        (void*)GetProcAddress(kernel_dll, "InitializeConditionVariable");
    cond_broadcast =
        (void*)GetProcAddress(kernel_dll, "WakeAllConditionVariable");
    cond_signal    =
        (void*)GetProcAddress(kernel_dll, "WakeConditionVariable");
    cond_wait      =
        (void*)GetProcAddress(kernel_dll, "SleepConditionVariableCS");
#endif

}

#endif /* FFMPEG_COMPAT_W32PTHREADS_H */
Commit	Line	Data
2ba45a60 DM	1	/*
	2	* Copyright (C) 2010-2011 x264 project
	3	*
	4	* Authors: Steven Walters <kemuri9@gmail.com>
	5	* Pegasys Inc. <http://www.pegasys-inc.com>
	6	*
	7	* This file is part of FFmpeg.
	8	*
	9	* FFmpeg is free software; you can redistribute it and/or
	10	* modify it under the terms of the GNU Lesser General Public
	11	* License as published by the Free Software Foundation; either
	12	* version 2.1 of the License, or (at your option) any later version.
	13	*
	14	* FFmpeg is distributed in the hope that it will be useful,
	15	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	17	* Lesser General Public License for more details.
	18	*
	19	* You should have received a copy of the GNU Lesser General Public
	20	* License along with FFmpeg; if not, write to the Free Software
	21	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	22	*/
	23
	24	/**
	25	* @file
	26	* w32threads to pthreads wrapper
	27	*/
	28
	29	#ifndef FFMPEG_COMPAT_W32PTHREADS_H
	30	#define FFMPEG_COMPAT_W32PTHREADS_H
	31
	32	/* Build up a pthread-like API using underlying Windows API. Have only static
	33	* methods so as to not conflict with a potentially linked in pthread-win32
	34	* library.
	35	* As most functions here are used without checking return values,
	36	* only implement return values as necessary. */
	37
	38	#define WIN32_LEAN_AND_MEAN
	39	#include <windows.h>
	40	#include <process.h>
	41
	42	#include "libavutil/attributes.h"
	43	#include "libavutil/common.h"
	44	#include "libavutil/internal.h"
	45	#include "libavutil/mem.h"
	46
	47	typedef struct pthread_t {
	48	void *handle;
	49	void (func)(void* arg);
	50	void *arg;
	51	void *ret;
	52	} pthread_t;
	53
	54	/* the conditional variable api for windows 6.0+ uses critical sections and
	55	* not mutexes */
	56	typedef CRITICAL_SECTION pthread_mutex_t;
	57
	58	/* This is the CONDITIONAL_VARIABLE typedef for using Window's native
	59	* conditional variables on kernels 6.0+.
	60	* MinGW does not currently have this typedef. */
	61	typedef struct pthread_cond_t {
	62	void *ptr;
	63	} pthread_cond_t;
	64
65	/* function pointers to conditional variable API on windows 6.0+ kernels */
66	#if _WIN32_WINNT < 0x0600
67	static void (WINAPI cond_broadcast)(pthread_cond_t cond);
68	static void (WINAPI cond_init)(pthread_cond_t cond);
69	static void (WINAPI cond_signal)(pthread_cond_t cond);
70	static BOOL (WINAPI cond_wait)(pthread_cond_t cond, pthread_mutex_t *mutex,
71	DWORD milliseconds);
72	#else
73	#define cond_init InitializeConditionVariable
74	#define cond_broadcast WakeAllConditionVariable
75	#define cond_signal WakeConditionVariable
76	#define cond_wait SleepConditionVariableCS
77
78	#define CreateEvent(a, reset, init, name) \
79	CreateEventEx(a, name, \
80	(reset ? CREATE_EVENT_MANUAL_RESET : 0) \| \
81	(init ? CREATE_EVENT_INITIAL_SET : 0), \
82	EVENT_ALL_ACCESS)
83	// CreateSemaphoreExA seems to be desktop-only, but as long as we don't
84	// use named semaphores, it doesn't matter if we use the W version.
85	#define CreateSemaphore(a, b, c, d) \
86	CreateSemaphoreExW(a, b, c, d, 0, SEMAPHORE_ALL_ACCESS)
87	#define InitializeCriticalSection(x) InitializeCriticalSectionEx(x, 0, 0)
88	#define WaitForSingleObject(a, b) WaitForSingleObjectEx(a, b, FALSE)
89	#endif
90
91	static av_unused unsigned __stdcall attribute_align_arg win32thread_worker(void *arg)
92	{
93	pthread_t *h = arg;
94	h->ret = h->func(h->arg);
95	return 0;
96	}
97
98	static av_unused int pthread_create(pthread_t thread, const void unused_attr,
99	void (start_routine)(void), void arg)
100	{
101	thread->func = start_routine;
102	thread->arg = arg;
103	thread->handle = (void*)_beginthreadex(NULL, 0, win32thread_worker, thread,
104	0, NULL);
105	return !thread->handle;
106	}
107
108	static av_unused void pthread_join(pthread_t thread, void **value_ptr)
109	{
110	DWORD ret = WaitForSingleObject(thread.handle, INFINITE);
111	if (ret != WAIT_OBJECT_0)
112	return;
113	if (value_ptr)
114	*value_ptr = thread.ret;
115	CloseHandle(thread.handle);
116	}
117
118	static inline int pthread_mutex_init(pthread_mutex_t m, void attr)
119	{
120	InitializeCriticalSection(m);
121	return 0;
122	}
123	static inline int pthread_mutex_destroy(pthread_mutex_t *m)
124	{
125	DeleteCriticalSection(m);
126	return 0;
127	}
128	static inline int pthread_mutex_lock(pthread_mutex_t *m)
129	{
130	EnterCriticalSection(m);
131	return 0;
132	}
133	static inline int pthread_mutex_unlock(pthread_mutex_t *m)
134	{
135	LeaveCriticalSection(m);
136	return 0;
137	}
138
139	/* for pre-Windows 6.0 platforms we need to define and use our own condition
140	* variable and api */
141	typedef struct win32_cond_t {
142	pthread_mutex_t mtx_broadcast;
143	pthread_mutex_t mtx_waiter_count;
144	volatile int waiter_count;
145	HANDLE semaphore;
146	HANDLE waiters_done;
147	volatile int is_broadcast;
148	} win32_cond_t;
149
150	static av_unused int pthread_cond_init(pthread_cond_t cond, const void unused_attr)
151	{
152	win32_cond_t *win32_cond = NULL;
153	if (cond_init) {
154	cond_init(cond);
155	return 0;
156	}
157
158	/* non native condition variables */
159	win32_cond = av_mallocz(sizeof(win32_cond_t));
160	if (!win32_cond)
161	return ENOMEM;
162	cond->ptr = win32_cond;
163	win32_cond->semaphore = CreateSemaphore(NULL, 0, 0x7fffffff, NULL);
164	if (!win32_cond->semaphore)
165	return ENOMEM;
166	win32_cond->waiters_done = CreateEvent(NULL, TRUE, FALSE, NULL);
167	if (!win32_cond->waiters_done)
168	return ENOMEM;
169
170	pthread_mutex_init(&win32_cond->mtx_waiter_count, NULL);
171	pthread_mutex_init(&win32_cond->mtx_broadcast, NULL);
172	return 0;
173	}
174
175	static av_unused void pthread_cond_destroy(pthread_cond_t *cond)
176	{
177	win32_cond_t *win32_cond = cond->ptr;
178	/* native condition variables do not destroy */
179	if (cond_init)
180	return;
181
182	/* non native condition variables */
183	CloseHandle(win32_cond->semaphore);
184	CloseHandle(win32_cond->waiters_done);
185	pthread_mutex_destroy(&win32_cond->mtx_waiter_count);
186	pthread_mutex_destroy(&win32_cond->mtx_broadcast);
187	av_freep(&win32_cond);
188	cond->ptr = NULL;
189	}
190
191	static av_unused void pthread_cond_broadcast(pthread_cond_t *cond)
192	{
193	win32_cond_t *win32_cond = cond->ptr;
194	int have_waiter;
195
196	if (cond_broadcast) {
197	cond_broadcast(cond);
198	return;
199	}
200
201	/* non native condition variables */
202	pthread_mutex_lock(&win32_cond->mtx_broadcast);
203	pthread_mutex_lock(&win32_cond->mtx_waiter_count);
204	have_waiter = 0;
205
206	if (win32_cond->waiter_count) {
207	win32_cond->is_broadcast = 1;
208	have_waiter = 1;
209	}
210
211	if (have_waiter) {
212	ReleaseSemaphore(win32_cond->semaphore, win32_cond->waiter_count, NULL);
213	pthread_mutex_unlock(&win32_cond->mtx_waiter_count);
214	WaitForSingleObject(win32_cond->waiters_done, INFINITE);
215	ResetEvent(win32_cond->waiters_done);
216	win32_cond->is_broadcast = 0;
217	} else
218	pthread_mutex_unlock(&win32_cond->mtx_waiter_count);
219	pthread_mutex_unlock(&win32_cond->mtx_broadcast);
220	}
221
222	static av_unused int pthread_cond_wait(pthread_cond_t cond, pthread_mutex_t mutex)
223	{
224	win32_cond_t *win32_cond = cond->ptr;
225	int last_waiter;
226	if (cond_wait) {
227	cond_wait(cond, mutex, INFINITE);
228	return 0;
229	}
230
231	/* non native condition variables */
232	pthread_mutex_lock(&win32_cond->mtx_broadcast);
233	pthread_mutex_lock(&win32_cond->mtx_waiter_count);
234	win32_cond->waiter_count++;
235	pthread_mutex_unlock(&win32_cond->mtx_waiter_count);
236	pthread_mutex_unlock(&win32_cond->mtx_broadcast);
237
238	// unlock the external mutex
239	pthread_mutex_unlock(mutex);
240	WaitForSingleObject(win32_cond->semaphore, INFINITE);
241
242	pthread_mutex_lock(&win32_cond->mtx_waiter_count);
243	win32_cond->waiter_count--;
244	last_waiter = !win32_cond->waiter_count \|\| !win32_cond->is_broadcast;
245	pthread_mutex_unlock(&win32_cond->mtx_waiter_count);
246
247	if (last_waiter)
248	SetEvent(win32_cond->waiters_done);
249
250	// lock the external mutex
251	return pthread_mutex_lock(mutex);
252	}
253
254	static av_unused void pthread_cond_signal(pthread_cond_t *cond)
255	{
256	win32_cond_t *win32_cond = cond->ptr;
257	int have_waiter;
258	if (cond_signal) {
259	cond_signal(cond);
260	return;
261	}
262
263	pthread_mutex_lock(&win32_cond->mtx_broadcast);
264
265	/* non-native condition variables */
266	pthread_mutex_lock(&win32_cond->mtx_waiter_count);
267	have_waiter = win32_cond->waiter_count;
268	pthread_mutex_unlock(&win32_cond->mtx_waiter_count);
269
270	if (have_waiter) {
271	ReleaseSemaphore(win32_cond->semaphore, 1, NULL);
272	WaitForSingleObject(win32_cond->waiters_done, INFINITE);
273	ResetEvent(win32_cond->waiters_done);
274	}
275
276	pthread_mutex_unlock(&win32_cond->mtx_broadcast);
277	}
278
279	static av_unused void w32thread_init(void)
280	{
281	#if _WIN32_WINNT < 0x0600
282	HANDLE kernel_dll = GetModuleHandle(TEXT("kernel32.dll"));
283	/* if one is available, then they should all be available */
284	cond_init =
285	(void*)GetProcAddress(kernel_dll, "InitializeConditionVariable");
286	cond_broadcast =
287	(void*)GetProcAddress(kernel_dll, "WakeAllConditionVariable");
288	cond_signal =
289	(void*)GetProcAddress(kernel_dll, "WakeConditionVariable");
290	cond_wait =
291	(void*)GetProcAddress(kernel_dll, "SleepConditionVariableCS");
292	#endif
293
294	}
295
296	#endif /* FFMPEG_COMPAT_W32PTHREADS_H */