1/* 2 * This file is part of FFmpeg. 3 * 4 * FFmpeg is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU Lesser General Public 6 * License as published by the Free Software Foundation; either 7 * version 2.1 of the License, or (at your option) any later version. 8 * 9 * FFmpeg is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 * Lesser General Public License for more details. 13 * 14 * You should have received a copy of the GNU Lesser General Public 15 * License along with FFmpeg; if not, write to the Free Software 16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 17 */ 18 19#include "internal.h" 20#include "libavutil/opt.h" 21#include "libavformat/avformat.h" 22 23int ff_alloc_input_device_context(AVFormatContext **avctx, const AVInputFormat *iformat, const char *format) 24{ 25 AVFormatContext *s; 26 int ret = 0; 27 28 *avctx = NULL; 29 if (!iformat && !format) 30 return AVERROR(EINVAL); 31 if (!(s = avformat_alloc_context())) 32 return AVERROR(ENOMEM); 33 34 if (!iformat) 35 iformat = av_find_input_format(format); 36 if (!iformat || !iformat->priv_class || !AV_IS_INPUT_DEVICE(iformat->priv_class->category)) { 37 ret = AVERROR(EINVAL); 38 goto error; 39 } 40 s->iformat = iformat; 41 if (s->iformat->priv_data_size > 0) { 42 s->priv_data = av_mallocz(s->iformat->priv_data_size); 43 if (!s->priv_data) { 44 ret = AVERROR(ENOMEM); 45 goto error; 46 } 47 if (s->iformat->priv_class) { 48 *(const AVClass**)s->priv_data= s->iformat->priv_class; 49 av_opt_set_defaults(s->priv_data); 50 } 51 } else 52 s->priv_data = NULL; 53 54 *avctx = s; 55 return 0; 56 error: 57 avformat_free_context(s); 58 return ret; 59} 60