| /* |
| * Multipart JPEG format |
| * Copyright (c) 2015 Luca Barbato |
| * |
| * 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 |
| */ |
| |
| #include "libavutil/avstring.h" |
| |
| #include "avformat.h" |
| #include "internal.h" |
| |
| static int get_line(AVIOContext *pb, char *line, int line_size) |
| { |
| int i = ff_get_line(pb, line, line_size); |
| |
| if (i > 1 && line[i - 2] == '\r') |
| line[i - 2] = '\0'; |
| |
| if (pb->error) |
| return pb->error; |
| |
| if (pb->eof_reached) |
| return AVERROR_EOF; |
| |
| return 0; |
| } |
| |
| static int split_tag_value(char **tag, char **value, char *line) |
| { |
| char *p = line; |
| |
| while (*p != '\0' && *p != ':') |
| p++; |
| if (*p != ':') |
| return AVERROR_INVALIDDATA; |
| |
| *p = '\0'; |
| *tag = line; |
| |
| p++; |
| |
| while (av_isspace(*p)) |
| p++; |
| |
| *value = p; |
| |
| return 0; |
| } |
| |
| static int check_content_type(char *line) |
| { |
| char *tag, *value; |
| int ret = split_tag_value(&tag, &value, line); |
| |
| if (ret < 0) |
| return ret; |
| |
| if (av_strcasecmp(tag, "Content-type") || |
| av_strcasecmp(value, "image/jpeg")) |
| return AVERROR_INVALIDDATA; |
| |
| return 0; |
| } |
| |
| static int mpjpeg_read_probe(AVProbeData *p) |
| { |
| AVIOContext *pb; |
| char line[128] = { 0 }; |
| int ret = 0; |
| |
| if (p->buf_size < 2 || p->buf[0] != '-' || p->buf[1] != '-') |
| return 0; |
| |
| pb = avio_alloc_context(p->buf, p->buf_size, 0, NULL, NULL, NULL, NULL); |
| if (!pb) |
| return AVERROR(ENOMEM); |
| |
| while (!pb->eof_reached) { |
| ret = get_line(pb, line, sizeof(line)); |
| if (ret < 0) |
| break; |
| |
| ret = check_content_type(line); |
| if (!ret) { |
| ret = AVPROBE_SCORE_MAX; |
| break; |
| } |
| } |
| |
| av_free(pb); |
| |
| return ret; |
| } |
| |
| static int mpjpeg_read_header(AVFormatContext *s) |
| { |
| AVStream *st; |
| char boundary[70 + 2 + 1]; |
| int64_t pos = avio_tell(s->pb); |
| int ret; |
| |
| |
| ret = get_line(s->pb, boundary, sizeof(boundary)); |
| if (ret < 0) |
| return ret; |
| |
| if (strncmp(boundary, "--", 2)) |
| return AVERROR_INVALIDDATA; |
| |
| st = avformat_new_stream(s, NULL); |
| if (!st) |
| return AVERROR(ENOMEM); |
| |
| st->codec->codec_type = AVMEDIA_TYPE_VIDEO; |
| st->codec->codec_id = AV_CODEC_ID_MJPEG; |
| |
| avpriv_set_pts_info(st, 60, 1, 25); |
| |
| avio_seek(s->pb, pos, SEEK_SET); |
| |
| return 0; |
| } |
| |
| static int parse_content_length(const char *value) |
| { |
| long int val = strtol(value, NULL, 10); |
| |
| if (val == LONG_MIN || val == LONG_MAX) |
| return AVERROR(errno); |
| if (val > INT_MAX) |
| return AVERROR(ERANGE); |
| return val; |
| } |
| |
| static int parse_multipart_header(AVFormatContext *s) |
| { |
| char line[128]; |
| int found_content_type = 0; |
| int ret, size = -1; |
| |
| ret = get_line(s->pb, line, sizeof(line)); |
| if (ret < 0) |
| return ret; |
| |
| if (strncmp(line, "--", 2)) |
| return AVERROR_INVALIDDATA; |
| |
| while (!s->pb->eof_reached) { |
| char *tag, *value; |
| |
| ret = get_line(s->pb, line, sizeof(line)); |
| if (ret < 0) |
| return ret; |
| |
| if (line[0] == '\0') |
| break; |
| |
| ret = split_tag_value(&tag, &value, line); |
| if (ret < 0) |
| return ret; |
| |
| if (!av_strcasecmp(tag, "Content-type")) { |
| if (av_strcasecmp(value, "image/jpeg")) { |
| av_log(s, AV_LOG_ERROR, |
| "Unexpected %s : %s\n", |
| tag, value); |
| return AVERROR_INVALIDDATA; |
| } else |
| found_content_type = 1; |
| } else if (!av_strcasecmp(tag, "Content-Length")) { |
| size = parse_content_length(value); |
| if (size < 0) |
| return size; |
| } |
| } |
| |
| if (!found_content_type || size < 0) { |
| return AVERROR_INVALIDDATA; |
| } |
| |
| return size; |
| } |
| |
| static int mpjpeg_read_packet(AVFormatContext *s, AVPacket *pkt) |
| { |
| int ret; |
| int size = parse_multipart_header(s); |
| |
| if (size < 0) |
| return size; |
| |
| ret = av_get_packet(s->pb, pkt, size); |
| if (ret < 0) |
| return ret; |
| |
| // trailing empty line |
| avio_skip(s->pb, 2); |
| |
| return 0; |
| } |
| |
| AVInputFormat ff_mpjpeg_demuxer = { |
| .name = "mpjpeg", |
| .long_name = NULL_IF_CONFIG_SMALL("MIME multipart JPEG"), |
| .mime_type = "multipart/x-mixed-replace", |
| .extensions = "mjpg", |
| .read_probe = mpjpeg_read_probe, |
| .read_header = mpjpeg_read_header, |
| .read_packet = mpjpeg_read_packet, |
| }; |