* Licensed under the GPL v2. For licencing details see COPYING.
*/
-/** \file fecdec_filter.c A filter fec-decodes an audio stream. */
+/** \file fecdec_filter.c A filter that fec-decodes an audio stream. */
+
+#include <regex.h>
#include <dirent.h>
#include "para.h"
*/
#define NUM_FEC_GROUPS 3
-/** Size of the output buffer of the fecdec filter. */
-#define FECDEC_OUTBUF_SIZE (1024 * 1024) /* FIXME: This has to depend on the fec params */
+/** Default size of the output buffer of the fecdec filter. */
+#define FECDEC_DEFAULT_OUTBUF_SIZE (3 * 1024)
+/** Maximal size of the output buffer of the fecdec filter. */
+#define FECDEC_MAX_OUTBUF_SIZE (1024 * 1024)
/** Data read from the header of a slice. */
struct fec_header {
uint8_t slices_per_group;
/** Number of slices needed to start decoding. */
uint8_t data_slices_per_group;
- /** Size of the ogg vorbis header (zero for mp3, aac). */
+ /** Size of the ogg vorbis/wma header (zero for mp3, aac). */
uint32_t audio_header_size;
/** Number of the FEC group this slice belongs to. */
uint32_t group_num;
struct fec_parms *fec;
/** Keeps track of what was received so far. */
struct fecdec_group groups[NUM_FEC_GROUPS];
+ /** Whether an audio file header was already received. */
int have_header;
+ /** Points to the first received group. */
+ struct fecdec_group *first_complete_group;
};
/** Iterate over all fecdec groups. */
#define FOR_EACH_FECDEC_GROUP(g, d) for (g = (d)->groups; \
- (g) - (d)->groups < NUM_FEC_GROUPS; (g)++)
+ (g) < (d)->groups + NUM_FEC_GROUPS; (g)++)
static int group_complete(struct fecdec_group *fg)
{
fg->idx[i] = -1;
}
free(fg->data);
+ fg->data = NULL;
free(fg->idx);
+ fg->idx = NULL;
fg->num_slices = 0;
memset(&fg->h, 0, sizeof(struct fec_header));
fg->num_received_slices = 0;
FOR_EACH_FECDEC_GROUP(fg, pfd) {
if (fg->h.group_num != h->group_num)
continue;
+ if (fg->num_received_slices == 0)
+ goto success;
if (fg->h.slices_per_group != h->slices_per_group)
- continue;
+ return -E_BAD_FEC_HEADER;
if (fg->h.data_slices_per_group != h->data_slices_per_group)
- continue;
+ return -E_BAD_FEC_HEADER;
+ if (fg->h.group_bytes != h->group_bytes)
+ return -E_BAD_FEC_HEADER;
+success:
*result = fg;
return 1;
}
FOR_EACH_FECDEC_GROUP(fg, pfd) {
if (!group_complete(fg))
continue;
+ /*
+ * Don't clear the first complete group if it has not yet been
+ * decoded.
+ */
+ if (fg == pfd->first_complete_group)
+ continue;
clear_group(fg);
return fg;
}
}
if (!group_complete(oldest) && !group_empty(oldest))
PARA_WARNING_LOG("Clearing incomplete group %d "
- "(contains %d slices)\n", fg->h.group_num,
- fg->num_received_slices);
+ "(contains %d slices)\n", oldest->h.group_num,
+ oldest->num_received_slices);
+ if (oldest == pfd->first_complete_group)
+ pfd->first_complete_group = NULL;
clear_group(oldest);
return oldest;
}
int r, slice_num;
if (group_complete(fg)) {
- PARA_DEBUG_LOG("group complete, ignoring slice %d\n",
- fg->h.slice_num);
+ PARA_DEBUG_LOG("group %d complete, ignoring slice %d\n",
+ fg->h.group_num, fg->h.slice_num);
fg->num_received_slices++;
return 0;
}
slice_num = fg->h.slice_num;
if (fg->num_slices == 0) {
fg->num_slices = fg->h.slices_per_group;
- fg->idx = malloc(fg->num_slices * sizeof(int));
- fg->data = malloc(fg->num_slices * sizeof(unsigned char *));
+ fg->idx = para_malloc(fg->num_slices * sizeof(int));
+ fg->data = para_malloc(fg->num_slices * sizeof(unsigned char *));
memset(fg->data, 0, fg->num_slices * sizeof(unsigned char *));
}
r = fg->num_received_slices;
fg->idx[r] = slice_num;
- fg->data[r] = malloc(fg->h.slice_bytes);
+ fg->data[r] = para_malloc(fg->h.slice_bytes);
memcpy(fg->data[r], buf, fg->h.slice_bytes);
fg->num_received_slices++;
return 1;
}
+/**
+ * The different states of a complete FEC group.
+ *
+ * Even if a FEC group has been received successfully, it probably can not be
+ * used right away because some streams (ogg, wma) need to receive an audio
+ * file header before decoding can start.
+ */
enum fec_group_usability {
+ /** Drop the group (because we did not receive the header yet). */
FEC_GROUP_UNUSABLE,
+ /** Use all data in the group. */
FEC_GROUP_USABLE,
+ /** Use the group, but drop its audio file header. */
FEC_GROUP_USABLE_SKIP_HEADER,
+ /** Use the group, including its header. */
+ FEC_GROUP_USABLE_WITH_HEADER
};
static enum fec_group_usability group_is_usable(struct fecdec_group *fg,
if (fg->h.bos)
return FEC_GROUP_USABLE;
if (fg->h.audio_header_size)
- return FEC_GROUP_USABLE;
+ return FEC_GROUP_USABLE_WITH_HEADER;
return FEC_GROUP_UNUSABLE;
}
static int decode_group(struct fecdec_group *fg, struct filter_node *fn)
{
int i, ret, sb = fg->h.slice_bytes;
- size_t written = 0;
+ size_t written, need;
struct private_fecdec_data *pfd = fn->private_data;
enum fec_group_usability u = group_is_usable(fg, pfd);
PARA_INFO_LOG("dropping unusable group %d\n", fg->h.group_num);
return 0;
}
- PARA_DEBUG_LOG("decoding group %d %d slices\n", fg->h.group_num,
+ PARA_DEBUG_LOG("decoding group %d (%d slices)\n", fg->h.group_num,
fg->h.data_slices_per_group);
ret = fec_decode(pfd->fec, fg->data, fg->idx, sb);
if (ret < 0)
PARA_DEBUG_LOG("writing group %d (%d/%d decoded data bytes)\n",
fg->h.group_num, fg->h.group_bytes,
fg->h.data_slices_per_group * sb);
+ need = fn->loaded + (fg->h.data_slices_per_group - i)* sb;
+ if (need > fn->bufsize) {
+ fn->bufsize = PARA_MAX(fn->bufsize * 2, need);
+ if (fn->bufsize > FECDEC_MAX_OUTBUF_SIZE)
+ return -E_FECDEC_OVERRUN;
+ PARA_INFO_LOG("increasing fec buf to %zu\n", fn->bufsize);
+ fn->buf = para_realloc(fn->buf, fn->bufsize);
+ }
+ if (u == FEC_GROUP_USABLE_WITH_HEADER) {
+ PARA_INFO_LOG("writing audio file header\n");
+ written = 0;
+ for (i = 0; i < fg->h.data_slices_per_group; i++) {
+ size_t n = sb;
+ if (written >= fg->h.audio_header_size)
+ break;
+ if (sb + written > fg->h.audio_header_size)
+ n = fg->h.audio_header_size - written;
+ memcpy(fn->buf + fn->loaded, fg->data[i], n);
+ fn->loaded += n;
+ written += n;
+ }
+ }
+ written = 0;
for (; i < fg->h.data_slices_per_group; i++) {
size_t n = sb;
if (n + written > fg->h.group_bytes)
n = fg->h.group_bytes - written;
- if (fn->loaded + n > fn->bufsize)
- return -E_FECDEC_OVERRUN;
memcpy(fn->buf + fn->loaded, fg->data[i], n);
fn->loaded += n;
written += n;
struct filter_node *fn)
{
struct fecdec_group *fg;
- int ret;
+ int ret, k, n;
struct private_fecdec_data *pfd = fn->private_data;
if (h->slice_bytes > len) /* can not use the thing, try to read more */
ret = get_group(h, pfd, &fg);
if (ret < 0)
return ret;
- if (!add_slice(buf, fg))
+ if (!add_slice(buf, fg)) /* group already complete */
+ return 1;
+ if (!group_complete(fg))
+ return 1;
+ /* this slice completed the group */
+ if (pfd->fec)
+ goto decode;
+ /* it's either the first or the second complete group */
+ if (!pfd->first_complete_group) { /* it's the first group */
+ enum fec_group_usability u = group_is_usable(fg, pfd);
+ assert(u != FEC_GROUP_USABLE_SKIP_HEADER);
+ if (u == FEC_GROUP_UNUSABLE) /* forget it */
+ return 1;
+ pfd->first_complete_group = fg; /* remember it */
return 1;
- if (group_complete(fg)) {
- if (!pfd->fec) {
- int k = h->data_slices_per_group, n = h->slices_per_group;
- PARA_NOTICE_LOG("init fec (%d, %d)\n", k, n);
- ret = fec_new(k, n, &pfd->fec);
- if (ret < 0)
- return ret;
- }
- ret = decode_group(fg, fn);
- if (ret < 0)
- return ret;
}
+ /* we have two complete groups, let's go */
+ k = h->data_slices_per_group;
+ n = h->slices_per_group;
+ PARA_NOTICE_LOG("init fec (%d, %d)\n", k, n);
+ ret = fec_new(k, n, &pfd->fec);
+ if (ret < 0)
+ return ret;
+ /* decode and clear the first group */
+ ret = decode_group(pfd->first_complete_group, fn);
+ if (ret < 0)
+ return ret;
+ clear_group(pfd->first_complete_group);
+ pfd->first_complete_group = NULL;
+decode:
+ ret = decode_group(fg, fn);
+ if (ret < 0)
+ return ret;
return 1;
}
ret = read_fec_header(buf, len, &h);
if (ret <= 0)
return ret;
- if (!h.slice_bytes || h.slice_bytes > fn->bufsize)
+ if (!h.slice_bytes)
return -E_BAD_SLICE_SIZE;
if (h.slice_num > h.slices_per_group)
return -E_BAD_SLICE_NUM;
static void fecdec_open(struct filter_node *fn)
{
- fn->bufsize = FECDEC_OUTBUF_SIZE;
+ struct private_fecdec_data *pfd;
+ fn->bufsize = FECDEC_DEFAULT_OUTBUF_SIZE;
fn->buf = para_malloc(fn->bufsize);
- fn->private_data = para_calloc(sizeof(struct private_fecdec_data));
+ pfd = para_calloc(sizeof(*pfd));
+ fn->private_data = pfd;
fn->loaded = 0;
}