Initial commit of all previous Chrome build scripts.

chromium/patches/to_upstream/45_mkv_fix_segmap_cache_overflow.patch

+Index: a/libavcodec/vp8.c
+===================================================================
+--- a/libavcodec/vp8.c  (revision 106016)
++++ b/libavcodec/vp8.c  (working copy)
+@@ -50,7 +50,8 @@
+     int ret;
+     if ((ret = ff_thread_get_buffer(s->avctx, f)) < 0)
+         return ret;
+-    if (!s->maps_are_invalid && s->num_maps_to_be_freed) {
++    if (s->num_maps_to_be_freed) {
++        assert(!s->maps_are_invalid);
+         f->ref_index[0] = s->segmentation_maps[--s->num_maps_to_be_freed];
+     } else if (!(f->ref_index[0] = av_mallocz(s->mb_width * s->mb_height))) {
+         ff_thread_release_buffer(s->avctx, f);
+@@ -59,39 +60,50 @@
+     return 0;
+ }
+ 
+-static void vp8_release_frame(VP8Context *s, AVFrame *f, int is_close)
++static void vp8_release_frame(VP8Context *s, AVFrame *f, int prefer_delayed_free, int can_direct_free)
+ {
+-    if (!is_close) {
+-        if (f->ref_index[0]) {
+-            assert(s->num_maps_to_be_freed < FF_ARRAY_ELEMS(s->segmentation_maps));
+-            s->segmentation_maps[s->num_maps_to_be_freed++] = f->ref_index[0];
++    if (f->ref_index[0]) {
++        if (prefer_delayed_free) {
++            /* Upon a size change, we want to free the maps but other threads may still
++             * be using them, so queue them. Upon a seek, all threads are inactive so
++             * we want to cache one to prevent re-allocation in the next decoding
++             * iteration, but the rest we can free directly. */
++            int max_queued_maps = can_direct_free ? 1 : FF_ARRAY_ELEMS(s->segmentation_maps);
++            if (s->num_maps_to_be_freed < max_queued_maps) {
++                s->segmentation_maps[s->num_maps_to_be_freed++] = f->ref_index[0];
++            } else if (can_direct_free) /* vp8_decode_flush(), but our queue is full */ {
++                av_free(f->ref_index[0]);
++            } /* else: MEMLEAK (should never happen, but better that than crash) */
+             f->ref_index[0] = NULL;
++        } else /* vp8_decode_free() */ {
++            av_free(f->ref_index[0]);
+         }
+-    } else {
+-        av_freep(&f->ref_index[0]);
+     }
+     ff_thread_release_buffer(s->avctx, f);
+ }
+ 
+-static void vp8_decode_flush_impl(AVCodecContext *avctx, int force, int is_close)
++static void vp8_decode_flush_impl(AVCodecContext *avctx,
++                                  int prefer_delayed_free, int can_direct_free, int free_mem)
+ {
+     VP8Context *s = avctx->priv_data;
+     int i;
+ 
+-    if (!avctx->is_copy || force) {
++    if (!avctx->is_copy) {
+         for (i = 0; i < 5; i++)
+             if (s->frames[i].data[0])
+-                vp8_release_frame(s, &s->frames[i], is_close);
++                vp8_release_frame(s, &s->frames[i], prefer_delayed_free, can_direct_free);
+     }
+     memset(s->framep, 0, sizeof(s->framep));
+ 
+-    free_buffers(s);
+-    s->maps_are_invalid = 1;
++    if (free_mem) {
++        free_buffers(s);
++        s->maps_are_invalid = 1;
++    }
+ }
+ 
+ static void vp8_decode_flush(AVCodecContext *avctx)
+ {
+-    vp8_decode_flush_impl(avctx, 0, 0);
++    vp8_decode_flush_impl(avctx, 1, 1, 0);
+ }
+ 
+ static int update_dimensions(VP8Context *s, int width, int height)
+@@ -101,7 +113,7 @@
+         if (av_image_check_size(width, height, 0, s->avctx))
+             return AVERROR_INVALIDDATA;
+ 
+-        vp8_decode_flush_impl(s->avctx, 1, 0);
++        vp8_decode_flush_impl(s->avctx, 1, 0, 1);
+ 
+         avcodec_set_dimensions(s->avctx, width, height);
+     }
+@@ -1579,7 +1591,7 @@
+             &s->frames[i] != s->framep[VP56_FRAME_PREVIOUS] &&
+             &s->frames[i] != s->framep[VP56_FRAME_GOLDEN] &&
+             &s->frames[i] != s->framep[VP56_FRAME_GOLDEN2])
+-            vp8_release_frame(s, &s->frames[i], 0);
++            vp8_release_frame(s, &s->frames[i], 1, 0);
+ 
+     // find a free buffer
+     for (i = 0; i < 5; i++)
+@@ -1595,7 +1607,7 @@
+         abort();
+     }
+     if (curframe->data[0])
+-        ff_thread_release_buffer(avctx, curframe);
++        vp8_release_frame(s, curframe, 1, 0);
+ 
+     curframe->key_frame = s->keyframe;
+     curframe->pict_type = s->keyframe ? AV_PICTURE_TYPE_I : AV_PICTURE_TYPE_P;
+@@ -1776,7 +1788,7 @@
+ 
+ static av_cold int vp8_decode_free(AVCodecContext *avctx)
+ {
+-    vp8_decode_flush_impl(avctx, 0, 1);
++    vp8_decode_flush_impl(avctx, 0, 1, 1);
+     release_queued_segmaps(avctx->priv_data, 1);
+     return 0;
+ }