MrBesen/ffmpeg
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

avformat/mpjpeg: allow processing of MIME parts without Content-Length header

Browse Source 
Fixes ticket 5023

Signed-off-by: Alex Agranovsky <alex@sighthound.com>
This commit is contained in:
Alex Agranovsky 2015-11-29 18:36:20 -05:00 committed by wm4
parent 97b8db334a
commit 79103f2199
1 changed files with 125 additions and 43 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

168
libavformat/mpjpegdec.c
View File

@ -23,13 +23,30 @@
#include "avformat.h"
#include "internal.h"
#include "avio_internal.h"
typedef struct MPJPEGDemuxContext {
char *boundary;
char *searchstr;
int searchstr_len;
} MPJPEGDemuxContext;
static void trim_right(char *p)
{
if (!p || !*p)
return;
char *end = p + strlen(p);
while (end > p && av_isspace(*(end-1)))
*(--end) = '\0';
}
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';
ff_get_line(pb, line, line_size);
if (pb->error)
return pb->error;
@ -37,21 +54,11 @@ static int get_line(AVIOContext *pb, char *line, int line_size)
if (pb->eof_reached)
return AVERROR_EOF;
trim_right(line);
return 0;
}
static void trim_right(char* p)
{
char *end;
if (!p || !*p)
return;
end = p + strlen(p) - 1;
while (end != p && av_isspace(*end)) {
*end = '\0';
end--;
}
}
static int split_tag_value(char **tag, char **value, char *line)
{
@ -86,12 +93,24 @@ static int split_tag_value(char **tag, char **value, char *line)
return 0;
}
static int parse_multipart_header(AVIOContext *pb, void *log_ctx);
static int parse_multipart_header(AVIOContext *pb,
int* size,
const char* expected_boundary,
void *log_ctx);
static int mpjpeg_read_close(AVFormatContext *s)
{
MPJPEGDemuxContext *mpjpeg = s->priv_data;
av_freep(&mpjpeg->boundary);
av_freep(&mpjpeg->searchstr);
return 0;
}
static int mpjpeg_read_probe(AVProbeData *p)
{
AVIOContext *pb;
int ret = 0;
int size = 0;
if (p->buf_size < 2 || p->buf[0] != '-' || p->buf[1] != '-')
return 0;
@ -100,7 +119,7 @@ static int mpjpeg_read_probe(AVProbeData *p)
if (!pb)
return 0;
ret = (parse_multipart_header(pb, NULL)>0)?AVPROBE_SCORE_MAX:0;
ret = (parse_multipart_header(pb, &size, "--", NULL) > 0) ? AVPROBE_SCORE_MAX : 0;
av_free(pb);
@ -110,14 +129,15 @@ static int mpjpeg_read_probe(AVProbeData *p)
static int mpjpeg_read_header(AVFormatContext *s)
{
AVStream *st;
char boundary[70 + 2 + 1];
char boundary[70 + 2 + 1] = {0};
int64_t pos = avio_tell(s->pb);
int ret;
ret = get_line(s->pb, boundary, sizeof(boundary));
if (ret < 0)
return ret;
do {
ret = get_line(s->pb, boundary, sizeof(boundary));
if (ret < 0)
return ret;
} while (!boundary[0]);
if (strncmp(boundary, "--", 2))
return AVERROR_INVALIDDATA;
@ -147,11 +167,16 @@ static int parse_content_length(const char *value)
return val;
}
static int parse_multipart_header(AVIOContext *pb, void *log_ctx)
static int parse_multipart_header(AVIOContext *pb,
int* size,
const char* expected_boundary,
void *log_ctx)
{
char line[128];
int found_content_type = 0;
int ret, size = -1;
int ret;
*size = -1;
// get the CRLF as empty string
ret = get_line(pb, line, sizeof(line));
@ -161,14 +186,21 @@ static int parse_multipart_header(AVIOContext *pb, void *log_ctx)
/* some implementation do not provide the required
* initial CRLF (see rfc1341 7.2.1)
*/
if (!line[0]) {
while (!line[0]) {
ret = get_line(pb, line, sizeof(line));
if (ret < 0)
return ret;
}
if (strncmp(line, "--", 2))
if (!av_strstart(line, expected_boundary, NULL)) {
av_log(log_ctx,
AV_LOG_ERROR,
"Expected boundary '%s' not found, instead found a line of %zu bytes\n",
expected_boundary,
strlen(line));
return AVERROR_INVALIDDATA;
}
while (!pb->eof_reached) {
char *tag, *value;
@ -191,42 +223,90 @@ static int parse_multipart_header(AVIOContext *pb, void *log_ctx)
if (!av_strcasecmp(tag, "Content-type")) {
if (av_strcasecmp(value, "image/jpeg")) {
if (log_ctx) {
av_log(log_ctx, AV_LOG_ERROR,
av_log(log_ctx, 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;
*size = parse_content_length(value);
if ( *size < 0 )
av_log(log_ctx, AV_LOG_WARNING,
"Invalid Content-Length value : %s\n",
value);
}
}
if (!found_content_type || size < 0) {
return AVERROR_INVALIDDATA;
}
return size;
return found_content_type ? 0 : AVERROR_INVALIDDATA;
}
static int mpjpeg_read_packet(AVFormatContext *s, AVPacket *pkt)
{
int size;
int ret;
int size = parse_multipart_header(s->pb, s);
if (size < 0)
return size;
MPJPEGDemuxContext *mpjpeg = s->priv_data;
if (mpjpeg->boundary == NULL) {
mpjpeg->boundary = av_strdup("--");
mpjpeg->searchstr = av_strdup("\r\n--");
if (!mpjpeg->boundary || !mpjpeg->searchstr) {
av_freep(&mpjpeg->boundary);
av_freep(&mpjpeg->searchstr);
return AVERROR(ENOMEM);
}
mpjpeg->searchstr_len = strlen(mpjpeg->searchstr);
}
ret = parse_multipart_header(s->pb, &size, mpjpeg->boundary, s);
ret = av_get_packet(s->pb, pkt, size);
if (ret < 0)
return ret;
return 0;
if (size > 0) {
/* size has been provided to us in MIME header */
ret = av_get_packet(s->pb, pkt, size);
} else {
/* no size was given -- we read until the next boundary or end-of-file */
int remaining = 0, len;
const int read_chunk = 2048;
av_init_packet(pkt);
pkt->data = NULL;
pkt->size = 0;
pkt->pos = avio_tell(s->pb);
/* we may need to return as much as all we've read back to the buffer */
ffio_ensure_seekback(s->pb, read_chunk);
while ((ret = av_append_packet(s->pb, pkt, read_chunk - remaining)) >= 0) {
/* scan the new data */
len = ret + remaining;
char *start = pkt->data + pkt->size - len;
do {
if (!memcmp(start, mpjpeg->searchstr, mpjpeg->searchstr_len)) {
// got the boundary! rewind the stream
avio_seek(s->pb, -(len-2), SEEK_CUR);
pkt->size -= (len-2);
return pkt->size;
}
len--;
start++;
} while (len >= mpjpeg->searchstr_len);
remaining = len;
}
/* error or EOF occurred */
if (ret == AVERROR_EOF) {
ret = pkt->size > 0 ? pkt->size : AVERROR_EOF;
} else {
av_packet_unref(pkt);
}
}
return ret;
}
AVInputFormat ff_mpjpeg_demuxer = {
@ -234,7 +314,9 @@ AVInputFormat ff_mpjpeg_demuxer = {
.long_name = NULL_IF_CONFIG_SMALL("MIME multipart JPEG"),
.mime_type = "multipart/x-mixed-replace",
.extensions = "mjpg",
.priv_data_size = sizeof(MPJPEGDemuxContext),
.read_probe = mpjpeg_read_probe,
.read_header = mpjpeg_read_header,
.read_packet = mpjpeg_read_packet,
.read_close = mpjpeg_read_close
};