tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
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threadprogress.c (2614B)


      1 /*
      2 * Copyright (c) 2022 Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
      3 *
      4 * This file is part of FFmpeg.
      5 *
      6 * FFmpeg is free software; you can redistribute it and/or
      7 * modify it under the terms of the GNU Lesser General Public
      8 * License as published by the Free Software Foundation; either
      9 * version 2.1 of the License, or (at your option) any later version.
     10 *
     11 * FFmpeg is distributed in the hope that it will be useful,
     12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
     13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     14 * Lesser General Public License for more details.
     15 *
     16 * You should have received a copy of the GNU Lesser General Public
     17 * License along with FFmpeg; if not, write to the Free Software
     18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
     19 */
     20 
     21 #include <limits.h>
     22 #include <stdatomic.h>
     23 
     24 #include "pthread_internal.h"
     25 #include "threadprogress.h"
     26 #include "libavutil/attributes.h"
     27 #include "libavutil/thread.h"
     28 
     29 DEFINE_OFFSET_ARRAY(ThreadProgress, thread_progress, init,
     30                    (offsetof(ThreadProgress, progress_mutex)),
     31                    (offsetof(ThreadProgress, progress_cond)));
     32 
     33 av_cold int ff_thread_progress_init(ThreadProgress *pro, int init_mode)
     34 {
     35    atomic_init(&pro->progress, init_mode ? -1 : INT_MAX);
     36 #if HAVE_THREADS
     37    if (init_mode)
     38        return ff_pthread_init(pro, thread_progress_offsets);
     39 #endif
     40    pro->init = init_mode;
     41    return 0;
     42 }
     43 
     44 av_cold void ff_thread_progress_destroy(ThreadProgress *pro)
     45 {
     46 #if HAVE_THREADS
     47    ff_pthread_free(pro, thread_progress_offsets);
     48 #else
     49    pro->init = 0;
     50 #endif
     51 }
     52 
     53 void ff_thread_progress_report(ThreadProgress *pro, int n)
     54 {
     55    if (atomic_load_explicit(&pro->progress, memory_order_relaxed) >= n)
     56        return;
     57 
     58    ff_mutex_lock(&pro->progress_mutex);
     59    atomic_store_explicit(&pro->progress, n, memory_order_release);
     60    ff_cond_broadcast(&pro->progress_cond);
     61    ff_mutex_unlock(&pro->progress_mutex);
     62 }
     63 
     64 void ff_thread_progress_await(const ThreadProgress *pro_c, int n)
     65 {
     66    /* Casting const away here is safe, because we only read from progress
     67     * and will leave pro_c in the same state upon leaving the function
     68     * as it had at the beginning. */
     69    ThreadProgress *pro = (ThreadProgress*)pro_c;
     70 
     71    if (atomic_load_explicit(&pro->progress, memory_order_acquire) >= n)
     72        return;
     73 
     74    ff_mutex_lock(&pro->progress_mutex);
     75    while (atomic_load_explicit(&pro->progress, memory_order_relaxed) < n)
     76        ff_cond_wait(&pro->progress_cond, &pro->progress_mutex);
     77    ff_mutex_unlock(&pro->progress_mutex);
     78 }