FFmpeg/libavcodec/pthread.c
Andreas Rheinhardt 20f9727018 avcodec/codec_internal: Add FFCodec, hide internal part of AVCodec
Up until now, codec.h contains both public and private parts
of AVCodec. This exposes the internals of AVCodec to users
and leads them into the temptation of actually using them
and forces us to forward-declare structures and types that
users can't use at all.

This commit changes this by adding a new structure FFCodec to
codec_internal.h that extends AVCodec, i.e. contains the public
AVCodec as first member; the private fields of AVCodec are moved
to this structure, leaving codec.h clean.

Reviewed-by: Anton Khirnov <anton@khirnov.net>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
2022-03-21 01:33:09 +01:00

129 lines
4.6 KiB
C

/*
* Copyright (c) 2004 Roman Shaposhnik
* Copyright (c) 2008 Alexander Strange (astrange@ithinksw.com)
*
* Many thanks to Steven M. Schultz for providing clever ideas and
* to Michael Niedermayer <michaelni@gmx.at> for writing initial
* implementation.
*
* 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
* Multithreading support functions
* @see doc/multithreading.txt
*/
#include "libavutil/thread.h"
#include "avcodec.h"
#include "codec_internal.h"
#include "pthread_internal.h"
#include "thread.h"
/**
* Set the threading algorithms used.
*
* Threading requires more than one thread.
* Frame threading requires entire frames to be passed to the codec,
* and introduces extra decoding delay, so is incompatible with low_delay.
*
* @param avctx The context.
*/
static void validate_thread_parameters(AVCodecContext *avctx)
{
int frame_threading_supported = (avctx->codec->capabilities & AV_CODEC_CAP_FRAME_THREADS)
#if FF_API_FLAG_TRUNCATED
&& !(avctx->flags & AV_CODEC_FLAG_TRUNCATED)
#endif
&& !(avctx->flags & AV_CODEC_FLAG_LOW_DELAY)
&& !(avctx->flags2 & AV_CODEC_FLAG2_CHUNKS);
if (avctx->thread_count == 1) {
avctx->active_thread_type = 0;
} else if (frame_threading_supported && (avctx->thread_type & FF_THREAD_FRAME)) {
avctx->active_thread_type = FF_THREAD_FRAME;
} else if (avctx->codec->capabilities & AV_CODEC_CAP_SLICE_THREADS &&
avctx->thread_type & FF_THREAD_SLICE) {
avctx->active_thread_type = FF_THREAD_SLICE;
} else if (!(ffcodec(avctx->codec)->caps_internal & FF_CODEC_CAP_AUTO_THREADS)) {
avctx->thread_count = 1;
avctx->active_thread_type = 0;
}
if (avctx->thread_count > MAX_AUTO_THREADS)
av_log(avctx, AV_LOG_WARNING,
"Application has requested %d threads. Using a thread count greater than %d is not recommended.\n",
avctx->thread_count, MAX_AUTO_THREADS);
}
int ff_thread_init(AVCodecContext *avctx)
{
validate_thread_parameters(avctx);
if (avctx->active_thread_type&FF_THREAD_SLICE)
return ff_slice_thread_init(avctx);
else if (avctx->active_thread_type&FF_THREAD_FRAME)
return ff_frame_thread_init(avctx);
return 0;
}
void ff_thread_free(AVCodecContext *avctx)
{
if (avctx->active_thread_type&FF_THREAD_FRAME)
ff_frame_thread_free(avctx, avctx->thread_count);
else
ff_slice_thread_free(avctx);
}
av_cold void ff_pthread_free(void *obj, const unsigned offsets[])
{
unsigned cnt = *(unsigned*)((char*)obj + offsets[0]);
const unsigned *cur_offset = offsets;
*(unsigned*)((char*)obj + offsets[0]) = 0;
for (; *(++cur_offset) != THREAD_SENTINEL && cnt; cnt--)
pthread_mutex_destroy((pthread_mutex_t*)((char*)obj + *cur_offset));
for (; *(++cur_offset) != THREAD_SENTINEL && cnt; cnt--)
pthread_cond_destroy ((pthread_cond_t *)((char*)obj + *cur_offset));
}
av_cold int ff_pthread_init(void *obj, const unsigned offsets[])
{
const unsigned *cur_offset = offsets;
unsigned cnt = 0;
int err;
#define PTHREAD_INIT_LOOP(type) \
for (; *(++cur_offset) != THREAD_SENTINEL; cnt++) { \
pthread_ ## type ## _t *dst = (void*)((char*)obj + *cur_offset); \
err = pthread_ ## type ## _init(dst, NULL); \
if (err) { \
err = AVERROR(err); \
goto fail; \
} \
}
PTHREAD_INIT_LOOP(mutex)
PTHREAD_INIT_LOOP(cond)
fail:
*(unsigned*)((char*)obj + offsets[0]) = cnt;
return err;
}