Auto-adjust fecdec output buffer size.

diff --git a/fecdec_filter.c b/fecdec_filter.c
index bc5300627dbdfb7a1ab1bf37f0ac5aa681dbd4a2..30ac818c360873f6aedadd19e55ca7e0f6209550 100644 (file)
--- a/fecdec_filter.c
+++ b/fecdec_filter.c
@@ -27,8 +27,10 @@
  */
 #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 (16 * 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 {
@@ -251,7 +253,7 @@ static enum fec_group_usability group_is_usable(struct fecdec_group *fg,
 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);
 
@@ -274,12 +276,18 @@ static int decode_group(struct fecdec_group *fg, struct filter_node *fn)
        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);
+       }
        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;
@@ -386,7 +394,7 @@ static void fecdec_close(struct filter_node *fn)
 
 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;