Obtain afs status items directly from afs.
[paraslash.git] / fecdec_filter.c
index 87b6a3669d6f1ab929dbf7a913f2bf237dcfaef6..a3cba9bbd0b3821b545a3aed6a7bb8606ec97b95 100644 (file)
  */
 #define NUM_FEC_GROUPS 3
 
-/** Size of the output buffer of the fecdec filter. */
-#define FECDEC_OUTBUF_SIZE 81920
+/** 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 {
@@ -46,6 +48,10 @@ struct fec_header {
        uint8_t slice_num;
        /** Used data bytes of this slice. */
        uint16_t slice_bytes;
+       /** Non-zero if this group is the beginning of the stream. */
+       uint8_t bos;
+       /** Non-zero if this stream embedds audio headers into fec groups. */
+       uint8_t header_stream;
 };
 
 /**
@@ -72,20 +78,16 @@ 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;
 };
 
 /** Iterate over all fecdec groups. */
 #define FOR_EACH_FECDEC_GROUP(g, d) for (g = (d)->groups; \
        (g) - (d)->groups < NUM_FEC_GROUPS; (g)++)
 
-/** */
-#define UNUSED_GROUP_NUM 0xffffffff
-
 static int group_complete(struct fecdec_group *fg)
 {
-       if (fg->h.group_num == UNUSED_GROUP_NUM)
-               return 0;
-       //PARA_INFO_LOG("received slices: %u, slices per group: %u\n", fg->num_received_slices, fg->h.data_slices_per_group);
        return fg->num_received_slices >= fg->h.data_slices_per_group;
 }
 
@@ -98,10 +100,6 @@ static void clear_group(struct fecdec_group *fg)
 {
        int i;
 
-       if (!group_complete(fg) && !group_empty(fg))
-               PARA_WARNING_LOG("Clearing incomplete group %d "
-                       "(contains %d slices)\n", fg->h.group_num,
-                       fg->num_received_slices);
        for (i = 0; i < fg->num_slices; i++) {
                free(fg->data[i]);
                fg->data[i] = NULL;
@@ -112,7 +110,6 @@ static void clear_group(struct fecdec_group *fg)
        fg->num_slices = 0;
        memset(&fg->h, 0, sizeof(struct fec_header));
        fg->num_received_slices = 0;
-       fg->h.group_num = UNUSED_GROUP_NUM;
 }
 
 static int find_group(struct fec_header *h,
@@ -123,7 +120,15 @@ static int find_group(struct fec_header *h,
        FOR_EACH_FECDEC_GROUP(fg, pfd) {
                if (fg->h.group_num != h->group_num)
                        continue;
-               /* FIXME: Add some more sanity checks here */
+               if (fg->num_received_slices == 0)
+                       goto success;
+               if (fg->h.slices_per_group != h->slices_per_group)
+                       return -E_BAD_FEC_HEADER;
+               if (fg->h.data_slices_per_group != h->data_slices_per_group)
+                       return -E_BAD_FEC_HEADER;
+               if (fg->h.group_bytes != h->group_bytes)
+                       return -E_BAD_FEC_HEADER;
+success:
                *result = fg;
                return 1;
        }
@@ -162,10 +167,15 @@ static struct fecdec_group *free_oldest_group(struct private_fecdec_data *pfd)
                if (!oldest || oldest->h.group_num > fg->h.group_num)
                        oldest = fg;
        }
+       if (!group_complete(oldest) && !group_empty(oldest))
+               PARA_WARNING_LOG("Clearing incomplete group %d "
+                       "(contains %d slices)\n", oldest->h.group_num,
+                       oldest->num_received_slices);
        clear_group(oldest);
        return oldest;
 }
 
+/* returns 1 if the group was found, 0 if not, negative on errors */
 static int get_group(struct fec_header *h, struct private_fecdec_data *pfd,
                struct fecdec_group **result)
 {
@@ -179,24 +189,33 @@ static int get_group(struct fec_header *h, struct private_fecdec_data *pfd,
        /* group not found */
        fg = find_unused_group(pfd);
        if (fg)
-               goto update_header;
+               goto success;
        fg = try_to_free_group(pfd);
        if (fg)
-               goto update_header;
+               goto success;
        fg = free_oldest_group(pfd);
-update_header:
-       fg->h = *h;
+       ret = 0;
 success:
+       fg->h = *h;
        *result = fg;
-       return 1;
+       return ret;
 }
 
+/*
+ * returns 1 if slice was added, zero otherwise (because the group was already
+ * complete). In any case the number of received slices is being increased by
+ * one.
+ */
 static int add_slice(char *buf, struct fecdec_group *fg)
 {
        int r, slice_num;
 
-       if (group_complete(fg))
+       if (group_complete(fg)) {
+               PARA_DEBUG_LOG("group complete, ignoring slice %d\n",
+                       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;
@@ -212,24 +231,69 @@ static int add_slice(char *buf, struct fecdec_group *fg)
        return 1;
 }
 
+enum fec_group_usability {
+       FEC_GROUP_UNUSABLE,
+       FEC_GROUP_USABLE,
+       FEC_GROUP_USABLE_SKIP_HEADER,
+};
+
+static enum fec_group_usability group_is_usable(struct fecdec_group *fg,
+               struct private_fecdec_data *pfd)
+{
+       struct fec_header *h = &fg->h;
+
+       if (!h->header_stream)
+               return FEC_GROUP_USABLE;
+       if (pfd->have_header) {
+               if (h->audio_header_size)
+                       return FEC_GROUP_USABLE_SKIP_HEADER;
+               return FEC_GROUP_USABLE;
+       }
+       if (fg->h.bos)
+               return FEC_GROUP_USABLE;
+       if (fg->h.audio_header_size)
+               return FEC_GROUP_USABLE;
+       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 = 0, need;
        struct private_fecdec_data *pfd = fn->private_data;
+       enum fec_group_usability u = group_is_usable(fg, pfd);
 
+       if (u == FEC_GROUP_UNUSABLE) {
+               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,
+               fg->h.data_slices_per_group);
        ret = fec_decode(pfd->fec, fg->data, fg->idx, sb);
        if (ret < 0)
                return ret;
+       pfd->have_header = 1;
+       i = 0;
+       if (u == FEC_GROUP_USABLE_SKIP_HEADER) {
+               i = ROUND_UP(fg->h.audio_header_size, fg->h.slice_bytes)
+                       / fg->h.slice_bytes;
+               PARA_DEBUG_LOG("skipping %d header slices\n", i);
+       }
        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);
-       for (i = 0; i < fg->h.data_slices_per_group; i++) {
+       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);
+       }
+       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;
@@ -261,13 +325,16 @@ static int read_fec_header(char *buf, size_t len, struct fec_header *h)
 
        h->slice_num = read_u8(buf + 18);
        h->slice_bytes = read_u16(buf + 20);
-       if (!h->group_bytes && & h->slice_bytes)
+       h->bos = read_u8(buf + 22);
+       h->header_stream = read_u8(buf + 23);
+       if (!memcmp(buf, FEC_EOF_PACKET, FEC_EOF_PACKET_LEN))
                return -E_FECDEC_EOF;
 //     PARA_DEBUG_LOG("group %u, slize %u, slices per group: %u\n",
 //             h->group_num, h->slice_num, h->slices_per_group);
        return 1;
 }
 
+/* returns 1 if we used the buffer, 0 if we didn't, negative on errors */
 static int dispatch_slice(char *buf, size_t len, struct fec_header *h,
                struct filter_node *fn)
 {
@@ -280,15 +347,8 @@ 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 (group_complete(fg)) {
-               PARA_DEBUG_LOG("group complete, ignoring slice %d\n",
-                       h->slice_num);
+       if (!add_slice(buf, fg))
                return 1;
-       }
-       fg->h = *h;
-       ret = add_slice(buf, fg);
-       if (ret < 0)
-               return ret;
        if (group_complete(fg)) {
                if (!pfd->fec) {
                        int k = h->data_slices_per_group, n = h->slices_per_group;
@@ -304,7 +364,7 @@ static int dispatch_slice(char *buf, size_t len, struct fec_header *h,
        return 1;
 }
 
-static int fecdec(char *buf, size_t len, struct filter_node *fn)
+static ssize_t fecdec(char *buf, size_t len, struct filter_node *fn)
 {
        int ret;
        struct fec_header h;
@@ -312,7 +372,7 @@ static int 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 > fn->bufsize)
+       if (!h.slice_bytes)
                return -E_BAD_SLICE_SIZE;
        if (h.slice_num > h.slices_per_group)
                return -E_BAD_SLICE_NUM;
@@ -333,13 +393,14 @@ static void fecdec_close(struct filter_node *fn)
                clear_group(fg);
        free(fn->buf);
        fn->buf = NULL;
+       fec_free(pfd->fec);
        free(fn->private_data);
        fn->private_data = NULL;
 }
 
 static void fecdec_open(struct filter_node *fn)
 {
-       fn->bufsize = FECDEC_OUTBUF_SIZE;
+       fn->bufsize = FECDEC_DEFAULT_OUTBUF_SIZE;
        fn->buf = para_malloc(fn->bufsize);
        fn->private_data = para_calloc(sizeof(struct private_fecdec_data));
        fn->loaded = 0;