From: Pierre-Anthony Lemieux <p...@palemieux.com>

IMF CPLs can reference thousands of files, which can result in system limits
for the number of open files to be exceeded. The following patch opens and
closes files as needed.

Addresses https://trac.ffmpeg.org/ticket/9623

---
 libavformat/imfdec.c | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/libavformat/imfdec.c b/libavformat/imfdec.c
index 847dead7f0..48bd5c78e8 100644
--- a/libavformat/imfdec.c
+++ b/libavformat/imfdec.c
@@ -103,10 +103,11 @@ typedef struct IMFVirtualTrackPlaybackCtx {
     int32_t index;                                 /**< Track index in 
playlist */
     AVRational current_timestamp;                  /**< Current temporal 
position */
     AVRational duration;                           /**< Overall duration */
-    uint32_t resource_count;                       /**< Number of resources */
+    uint32_t resource_count;                       /**< Number of resources 
(<= INT32_MAX) */
     unsigned int resources_alloc_sz;               /**< Size of the buffer 
holding the resource */
     IMFVirtualTrackResourcePlaybackCtx *resources; /**< Buffer holding the 
resources */
-    uint32_t current_resource_index;               /**< Current resource */
+    int32_t current_resource_index;                /**< Index of the current 
resource in resources,
+                                                        or < 0 if a current 
resource has yet to be selected */
     int64_t last_pts;                              /**< Last timestamp */
 } IMFVirtualTrackPlaybackCtx;
 
@@ -435,7 +436,6 @@ static int open_track_file_resource(AVFormatContext *s,
     IMFContext *c = s->priv_data;
     IMFAssetLocator *asset_locator;
     void *tmp;
-    int ret;
 
     asset_locator = find_asset_map_locator(&c->asset_locator_map, 
track_file_resource->track_file_uuid);
     if (!asset_locator) {
@@ -452,7 +452,7 @@ static int open_track_file_resource(AVFormatContext *s,
            UID_ARG(asset_locator->uuid),
            asset_locator->absolute_uri);
 
-    if (track->resource_count > UINT32_MAX - 
track_file_resource->base.repeat_count
+    if (track->resource_count > INT32_MAX - 
track_file_resource->base.repeat_count
         || (track->resource_count + track_file_resource->base.repeat_count)
             > INT_MAX / sizeof(IMFVirtualTrackResourcePlaybackCtx))
         return AVERROR(ENOMEM);
@@ -470,8 +470,6 @@ static int open_track_file_resource(AVFormatContext *s,
         vt_ctx.locator = asset_locator;
         vt_ctx.resource = track_file_resource;
         vt_ctx.ctx = NULL;
-        if ((ret = open_track_resource_context(s, &vt_ctx)) != 0)
-            return ret;
         track->resources[track->resource_count++] = vt_ctx;
         track->duration = av_add_q(track->duration,
                                    
av_make_q((int)track_file_resource->base.duration
@@ -501,6 +499,7 @@ static int open_virtual_track(AVFormatContext *s,
 
     if (!(track = av_mallocz(sizeof(IMFVirtualTrackPlaybackCtx))))
         return AVERROR(ENOMEM);
+    track->current_resource_index = -1;
     track->index = track_index;
     track->duration = av_make_q(0, 1);
 
@@ -551,6 +550,9 @@ static int set_context_streams_from_tracks(AVFormatContext 
*s)
         AVStream *first_resource_stream;
 
         /* Open the first resource of the track to get stream information */
+        ret = open_track_resource_context(s, &c->tracks[i]->resources[0]);
+        if (ret)
+            return ret;
         first_resource_stream = c->tracks[i]->resources[0].ctx->streams[0];
         av_log(s, AV_LOG_DEBUG, "Open the first resource of track %d\n", 
c->tracks[i]->index);
 
@@ -741,7 +743,8 @@ static IMFVirtualTrackResourcePlaybackCtx 
*get_resource_context_for_timestamp(AV
                        track->index);
                 if (open_track_resource_context(s, &(track->resources[i])) != 
0)
                     return NULL;
-                
avformat_close_input(&(track->resources[track->current_resource_index].ctx));
+                if (track->current_resource_index > 0)
+                    
avformat_close_input(&track->resources[track->current_resource_index].ctx);
                 track->current_resource_index = i;
             }
 
-- 
2.17.1

_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-devel

To unsubscribe, visit link above, or email
ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".

Reply via email to