* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
+#include "libavutil/avassert.h"
#include "libavutil/imgutils.h"
#include "parser.h" //for ParseContext
#include "pnm.h"
+typedef struct PNMParseContext {
+ ParseContext pc;
+ int remaining_bytes;
+ int ascii_scan;
+}PNMParseContext;
static int pnm_parse(AVCodecParserContext *s, AVCodecContext *avctx,
const uint8_t **poutbuf, int *poutbuf_size,
const uint8_t *buf, int buf_size)
{
- ParseContext *pc = s->priv_data;
+ PNMParseContext *pnmpc = s->priv_data;
+ ParseContext *pc = &pnmpc->pc;
PNMContext pnmctx;
- int next;
+ int next = END_NOT_FOUND;
+ int skip = 0;
- for (; pc->overread > 0; pc->overread--) {
- pc->buffer[pc->index++]= pc->buffer[pc->overread_index++];
+ if (pc->overread > 0) {
+ memmove(pc->buffer + pc->index, pc->buffer + pc->overread_index, pc->overread);
+ pc->index += pc->overread;
+ pc->overread_index += pc->overread;
+ pc->overread = 0;
}
+
+ if (pnmpc->remaining_bytes) {
+ int inc = FFMIN(pnmpc->remaining_bytes, buf_size);
+ skip += inc;
+ pnmpc->remaining_bytes -= inc;
+
+ if (!pnmpc->remaining_bytes)
+ next = skip;
+ goto end;
+ }
+
retry:
if (pc->index) {
pnmctx.bytestream_start =
pnmctx.bytestream_end = pc->buffer + pc->index;
} else {
pnmctx.bytestream_start =
- pnmctx.bytestream = (uint8_t *) buf; /* casts avoid warnings */
- pnmctx.bytestream_end = (uint8_t *) buf + buf_size;
+ pnmctx.bytestream = (uint8_t *) buf + skip; /* casts avoid warnings */
+ pnmctx.bytestream_end = (uint8_t *) buf + buf_size - skip;
}
if (ff_pnm_decode_header(avctx, &pnmctx) < 0) {
if (pnmctx.bytestream < pnmctx.bytestream_end) {
if (pc->index) {
pc->index = 0;
+ pnmpc->ascii_scan = 0;
} else {
unsigned step = FFMAX(1, pnmctx.bytestream - pnmctx.bytestream_start);
- buf += step;
- buf_size -= step;
+
+ skip += step;
}
goto retry;
}
- next = END_NOT_FOUND;
} else if (pnmctx.type < 4) {
- next = END_NOT_FOUND;
+ uint8_t *bs = pnmctx.bytestream;
+ const uint8_t *end = pnmctx.bytestream_end;
+ uint8_t *sync = bs;
+
+ if (pc->index) {
+ av_assert0(pnmpc->ascii_scan <= end - bs);
+ bs += pnmpc->ascii_scan;
+ }
+
+ while (bs < end) {
+ int c;
+ sync = bs;
+ c = *bs++;
+ if (c == '#') {
+ uint8_t *match = memchr(bs, '\n', end-bs);
+ if (match)
+ bs = match + 1;
+ else
+ break;
+ } else if (c == 'P') {
+ next = bs - pnmctx.bytestream_start + skip - 1;
+ pnmpc->ascii_scan = 0;
+ break;
+ }
+ }
+ if (next == END_NOT_FOUND)
+ pnmpc->ascii_scan = sync - pnmctx.bytestream + skip;
} else {
- next = pnmctx.bytestream - pnmctx.bytestream_start
- + av_image_get_buffer_size(avctx->pix_fmt, avctx->width, avctx->height, 1);
- if (pnmctx.bytestream_start != buf)
- next -= pc->index;
- if (next > buf_size)
- next = END_NOT_FOUND;
+ int ret = av_image_get_buffer_size(avctx->pix_fmt, avctx->width, avctx->height, 1);
+ next = pnmctx.bytestream - pnmctx.bytestream_start + skip;
+ if (ret >= 0 && next + (uint64_t)ret <= INT_MAX)
+ next += ret;
}
-
+ if (next != END_NOT_FOUND && pnmctx.bytestream_start != buf + skip)
+ next -= pc->index;
+ if (next > buf_size) {
+ pnmpc->remaining_bytes = next - buf_size;
+ next = END_NOT_FOUND;
+ }
+end:
if (ff_combine_frame(pc, next, &buf, &buf_size) < 0) {
*poutbuf = NULL;
*poutbuf_size = 0;
return next;
}
-AVCodecParser ff_pnm_parser = {
+const AVCodecParser ff_pnm_parser = {
.codec_ids = { AV_CODEC_ID_PGM, AV_CODEC_ID_PGMYUV, AV_CODEC_ID_PPM,
AV_CODEC_ID_PBM, AV_CODEC_ID_PAM },
- .priv_data_size = sizeof(ParseContext),
+ .priv_data_size = sizeof(PNMParseContext),
.parser_parse = pnm_parse,
.parser_close = ff_parse_close,
};