#define MAD_TO_SHORT(f) (f) >= MAD_F_ONE? SHRT_MAX :\
(f) <= -MAD_F_ONE? -SHRT_MAX : (signed short) ((f) >> (MAD_F_FRACBITS - 15))
+/** State of the decoding process. */
+enum mp3dec_flags {
+ /** Bad main_data_begin pointer encounterd. */
+ MP3DEC_FLAG_BAD_DATA = 1,
+ /** Some output has already been produced. */
+ MP3DEC_FLAG_DECODE_STARTED = 2,
+};
+
/** Data specific to the mp3dec filter. */
struct private_mp3dec_data {
/** Information on the current mp3 stream. */
struct mad_frame frame;
/** Contains the PCM output. */
struct mad_synth synth;
+ /** See \ref mp3dec_flags. */
+ unsigned flags;
+ /** Defer decoding until this time. */
+ struct timeval stream_start_barrier;
+ /** Wait until this many input bytes are available. */
+ size_t input_len_barrier;
};
+static int need_bad_data_delay(struct private_mp3dec_data *pmd,
+ size_t bytes_available)
+{
+ if (!(pmd->flags & MP3DEC_FLAG_BAD_DATA))
+ return 0;
+ if (pmd->flags & MP3DEC_FLAG_DECODE_STARTED)
+ return 0;
+ if (bytes_available >= pmd->input_len_barrier)
+ return 0;
+ if (tv_diff(now, &pmd->stream_start_barrier, NULL) > 0)
+ return 0;
+ return 1;
+}
+
+/*
+ * Returns negative on serious errors, zero if the error should be ignored and
+ * positive on bad data pointer errors at stream start.
+ */
+static int handle_decode_error(struct private_mp3dec_data *pmd, size_t len)
+{
+ if (!MAD_RECOVERABLE(pmd->stream.error)
+ && pmd->stream.error != MAD_ERROR_BUFLEN) {
+ PARA_ERROR_LOG("%s\n", mad_stream_errorstr(&pmd->stream));
+ return -E_MAD_FRAME_DECODE;
+ }
+ PARA_DEBUG_LOG("%s\n", mad_stream_errorstr(&pmd->stream));
+ if (pmd->stream.error != MAD_ERROR_BADDATAPTR)
+ return 0;
+ if (pmd->flags & MP3DEC_FLAG_DECODE_STARTED)
+ return 0;
+ /*
+ * Bad data pointer at stream start. Defer decoding until the amount of
+ * data we are about to skip is available again, but wait at most 60ms.
+ */
+ pmd->flags |= MP3DEC_FLAG_BAD_DATA;
+ pmd->input_len_barrier = len;
+ tv_add(now, &(struct timeval){0, 60 * 1000},
+ &pmd->stream_start_barrier);
+ return 1;
+}
+
static ssize_t mp3dec(char *inbuffer, size_t len, struct filter_node *fn)
{
int i, ret;
if (fn->loaded + 16384 > fn->bufsize)
return 0;
+ if (need_bad_data_delay(pmd, len))
+ return 0;
mad_stream_buffer(&pmd->stream, (unsigned char *) inbuffer, copy);
pmd->stream.error = 0;
next_frame:
fn->fc->samplerate = pmd->frame.header.samplerate;
fn->fc->channels = MAD_NCHANNELS(&pmd->frame.header);
ret = mad_frame_decode(&pmd->frame, &pmd->stream);
- if (ret) {
- if (MAD_RECOVERABLE(pmd->stream.error) ||
- pmd->stream.error == MAD_ERROR_BUFLEN) {
- PARA_DEBUG_LOG("frame decode: %s\n",
- mad_stream_errorstr(&pmd->stream));
+ if (ret != 0) {
+ ret = handle_decode_error(pmd, len);
+ if (ret < 0)
+ return ret;
+ if (ret == 0)
goto out;
- }
- PARA_ERROR_LOG("frame decode: %s\n",
- mad_stream_errorstr(&pmd->stream));
- return -E_MAD_FRAME_DECODE;
+ ret = copy - (pmd->stream.bufend - pmd->stream.next_frame);
+ PARA_NOTICE_LOG("skipping %d input bytes\n", ret);
+ return ret;
}
mad_synth_frame(&pmd->synth, &pmd->frame);
+ pmd->flags |= MP3DEC_FLAG_DECODE_STARTED;
for (i = 0; i < pmd->synth.pcm.length; i++) {
int s = MAD_TO_SHORT(pmd->synth.pcm.samples[0][i]);