X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=blobdiff_plain;f=fecdec_filter.c;h=ca7c7dd3522eae673469baee46e7a7471e7fac72;hp=1f57dd123eb86d906740f347a58a6d8ab27c28cf;hb=9f7aecdbca21d6cadfe36ac46f6f0dada92ce8f2;hpb=343f3c63fc3a7f9ca4ba4163c9e4cf06cde8d0c3

diff --git a/fecdec_filter.c b/fecdec_filter.c
index 1f57dd12..ca7c7dd3 100644
--- a/fecdec_filter.c
+++ b/fecdec_filter.c
@@ -4,7 +4,9 @@
  * 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"
@@ -78,12 +80,15 @@ struct private_fecdec_data {
 	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)
 {
@@ -105,7 +110,9 @@ static void clear_group(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;
@@ -152,6 +159,12 @@ static struct fecdec_group *try_to_free_group(struct private_fecdec_data *pfd)
 	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;
 	}
@@ -170,6 +183,8 @@ static struct fecdec_group *free_oldest_group(struct private_fecdec_data *pfd)
 		PARA_WARNING_LOG("Clearing incomplete group %d "
 			"(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;
 }
@@ -210,30 +225,42 @@ static int add_slice(char *buf, struct fecdec_group *fg)
 	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,
@@ -251,14 +278,14 @@ 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, need;
+	size_t written, need;
 	struct private_fecdec_data *pfd = fn->private_data;
 	enum fec_group_usability u = group_is_usable(fg, pfd);
 
@@ -266,7 +293,7 @@ static int decode_group(struct fecdec_group *fg, struct filter_node *fn)
 		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)
@@ -289,6 +316,21 @@ static int decode_group(struct fecdec_group *fg, struct filter_node *fn)
 		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)
@@ -338,7 +380,7 @@ static int dispatch_slice(char *buf, size_t len, struct fec_header *h,
 		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 */
@@ -346,20 +388,39 @@ static int dispatch_slice(char *buf, size_t len, struct fec_header *h,
 	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;
 }
 
@@ -371,7 +432,7 @@ static ssize_t fecdec(char *buf, size_t len, struct filter_node *fn)
 	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;
@@ -399,9 +460,11 @@ static void fecdec_close(struct filter_node *fn)
 
 static void fecdec_open(struct filter_node *fn)
 {
+	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;
 }