/* * 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 * Libavfilter multithreading support */ #include <stddef.h> #include "libavutil/error.h"#include "libavutil/macros.h"#include "libavutil/mem.h"#include "libavutil/slicethread.h" #include "avfilter.h"#include "internal.h"#include "thread.h" typedef struct ThreadContext {    AVFilterGraph *graph;    AVSliceThread *thread;    avfilter_action_func *func;     /* per-execute parameters */    AVFilterContext *ctx;    void *arg;    int   *rets;} ThreadContext; static void worker_func(void *priv, int jobnr, int threadnr, int nb_jobs, int nb_threads){    ThreadContext *c = priv;    int ret = c->func(c->ctx, c->arg, jobnr, nb_jobs);    if (c->rets)        c->rets[jobnr] = ret;} static void slice_thread_uninit(ThreadContext *c){    avpriv_slicethread_free(&c->thread);} static int thread_execute(AVFilterContext *ctx, avfilter_action_func *func,                          void *arg, int *ret, int nb_jobs){    ThreadContext *c = ctx->graph->internal->thread;     if (nb_jobs <= 0)        return 0;    c->ctx         = ctx;    c->arg         = arg;    c->func        = func;    c->rets        = ret;     avpriv_slicethread_execute(c->thread, nb_jobs, 0);    return 0;} static int thread_init_internal(ThreadContext *c, int nb_threads){    nb_threads = avpriv_slicethread_create(&c->thread, c, worker_func, NULL, nb_threads);    if (nb_threads <= 1)        avpriv_slicethread_free(&c->thread);    return FFMAX(nb_threads, 1);} int ff_graph_thread_init(AVFilterGraph *graph){    int ret;     if (graph->nb_threads == 1) {        graph->thread_type = 0;        return 0;    }     graph->internal->thread = av_mallocz(sizeof(ThreadContext));    if (!graph->internal->thread)        return AVERROR(ENOMEM);     ret = thread_init_internal(graph->internal->thread, graph->nb_threads);    if (ret <= 1) {        av_freep(&graph->internal->thread);        graph->thread_type = 0;        graph->nb_threads  = 1;        return (ret < 0) ? ret : 0;    }    graph->nb_threads = ret;     graph->internal->thread_execute = thread_execute;     return 0;} void ff_graph_thread_free(AVFilterGraph *graph){    if (graph->internal->thread)        slice_thread_uninit(graph->internal->thread);    av_freep(&graph->internal->thread);}