FFmpeg: libavformat/options.c Source File

00001 /*
00002  * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
00003  *
00004  * This file is part of FFmpeg.
00005  *
00006  * FFmpeg is free software; you can redistribute it and/or
00007  * modify it under the terms of the GNU Lesser General Public
00008  * License as published by the Free Software Foundation; either
00009  * version 2.1 of the License, or (at your option) any later version.
00010  *
00011  * FFmpeg is distributed in the hope that it will be useful,
00012  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00013  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00014  * Lesser General Public License for more details.
00015  *
00016  * You should have received a copy of the GNU Lesser General Public
00017  * License along with FFmpeg; if not, write to the Free Software
00018  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00019  */
00020 #include "avformat.h"
00021 #include "avio_internal.h"
00022 #include "libavutil/opt.h"
00023 
00029 #include "options_table.h"
00030 
00031 static const char* format_to_name(void* ptr)
00032 {
00033     AVFormatContext* fc = (AVFormatContext*) ptr;
00034     if(fc->iformat) return fc->iformat->name;
00035     else if(fc->oformat) return fc->oformat->name;
00036     else return "NULL";
00037 }
00038 
00039 static void *format_child_next(void *obj, void *prev)
00040 {
00041     AVFormatContext *s = obj;
00042     if (!prev && s->priv_data &&
00043         ((s->iformat && s->iformat->priv_class) ||
00044           s->oformat && s->oformat->priv_class))
00045         return s->priv_data;
00046     if (s->pb && s->pb->av_class && prev != s->pb)
00047         return s->pb;
00048     return NULL;
00049 }
00050 
00051 static const AVClass *format_child_class_next(const AVClass *prev)
00052 {
00053     AVInputFormat  *ifmt = NULL;
00054     AVOutputFormat *ofmt = NULL;
00055 
00056     if (!prev)
00057         return &ffio_url_class;
00058 
00059     while ((ifmt = av_iformat_next(ifmt)))
00060         if (ifmt->priv_class == prev)
00061             break;
00062 
00063     if (!ifmt)
00064         while ((ofmt = av_oformat_next(ofmt)))
00065             if (ofmt->priv_class == prev)
00066                 break;
00067     if (!ofmt)
00068         while (ifmt = av_iformat_next(ifmt))
00069             if (ifmt->priv_class)
00070                 return ifmt->priv_class;
00071 
00072     while (ofmt = av_oformat_next(ofmt))
00073         if (ofmt->priv_class)
00074             return ofmt->priv_class;
00075 
00076     return NULL;
00077 }
00078 
00079 static const AVClass av_format_context_class = {
00080     .class_name     = "AVFormatContext",
00081     .item_name      = format_to_name,
00082     .option         = options,
00083     .version        = LIBAVUTIL_VERSION_INT,
00084     .child_next     = format_child_next,
00085     .child_class_next = format_child_class_next,
00086 };
00087 
00088 static void avformat_get_context_defaults(AVFormatContext *s)
00089 {
00090     memset(s, 0, sizeof(AVFormatContext));
00091 
00092     s->av_class = &av_format_context_class;
00093 
00094     av_opt_set_defaults(s);
00095 }
00096 
00097 AVFormatContext *avformat_alloc_context(void)
00098 {
00099     AVFormatContext *ic;
00100     ic = av_malloc(sizeof(AVFormatContext));
00101     if (!ic) return ic;
00102     avformat_get_context_defaults(ic);
00103     return ic;
00104 }
00105 
00106 const AVClass *avformat_get_class(void)
00107 {
00108     return &av_format_context_class;
00109 }