subviewer: sanitize packets.

The data does not contain timing or trailing line breaks anymore. In
addition to being less idiotic, it is consistent with other codecs and
thus allows more switches between formats and codecs. It also fixes the
issue of the trailing line returns being simple \n instead of CRLF in
the ASS rectangle dialogue (this is the reason of the FATE update).

libavcodec/subviewerdec.c

@@ -31,17 +31,13 @@
 static int subviewer_event_to_ass(AVBPrint *buf, const char *p)
 {
     while (*p) {
-        char c;
-
-        if (sscanf(p, "%*u:%*u:%*u.%*u,%*u:%*u:%*u.%*u%c", &c) == 1)
-            p += strcspn(p, "\n") + 1;
         if (!strncmp(p, "[br]", 4)) {
             av_bprintf(buf, "\\N");
             p += 4;
         } else {
             if (p[0] == '\n' && p[1])
                 av_bprintf(buf, "\\N");
-            else if (*p != '\r')
+            else if (*p != '\n' && *p != '\r')
                 av_bprint_chars(buf, *p, 1);
             p++;
         }
@@ -54,10 +50,19 @@ static int subviewer_event_to_ass(AVBPrint *buf, const char *p)
 static int subviewer_decode_frame(AVCodecContext *avctx,
                                   void *data, int *got_sub_ptr, AVPacket *avpkt)
 {
+    char c;
     AVSubtitle *sub = data;
     const char *ptr = avpkt->data;
     AVBPrint buf;
 
+    /* To be removed later */
+    if (sscanf(ptr, "%*u:%*u:%*u.%*u,%*u:%*u:%*u.%*u%c", &c) == 1) {
+        av_log(avctx, AV_LOG_ERROR, "AVPacket is not clean (contains timing "
+               "information). You need to upgrade your libavformat or "
+               "sanitize your packet.\n");
+        return AVERROR_INVALIDDATA;
+    }
+
     av_bprint_init(&buf, 0, AV_BPRINT_SIZE_UNLIMITED);
     // note: no need to rescale pts & duration since they are in the same
     // timebase as ASS (1/100)

libavcodec/version.h

@@ -30,7 +30,7 @@
 
 #define LIBAVCODEC_VERSION_MAJOR 54
 #define LIBAVCODEC_VERSION_MINOR 85
-#define LIBAVCODEC_VERSION_MICRO 100
+#define LIBAVCODEC_VERSION_MICRO 101
 
 #define LIBAVCODEC_VERSION_INT  AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
                                                LIBAVCODEC_VERSION_MINOR, \

libavformat/subviewerdec.c

@@ -71,7 +71,10 @@ static int subviewer_read_header(AVFormatContext *s)
     SubViewerContext *subviewer = s->priv_data;
     AVStream *st = avformat_new_stream(s, NULL);
     AVBPrint header;
-    int res = 0;
+    int res = 0, new_event = 1;
+    int64_t pts_start = AV_NOPTS_VALUE;
+    int duration = -1;
+    AVPacket *sub = NULL;
 
     if (!st)
         return AVERROR(ENOMEM);
@@ -83,12 +86,14 @@ static int subviewer_read_header(AVFormatContext *s)
 
     while (!url_feof(s->pb)) {
         char line[2048];
-        const int64_t pos = avio_tell(s->pb);
+        int64_t pos = 0;
         int len = ff_get_line(s->pb, line, sizeof(line));
 
         if (!len)
             break;
 
+        line[strcspn(line, "\r\n")] = 0;
+
         if (line[0] == '[' && strncmp(line, "[br]", 4)) {
 
             /* ignore event style, XXX: add to side_data? */
@@ -97,7 +102,7 @@ static int subviewer_read_header(AVFormatContext *s)
                 continue;
 
             if (!st->codec->extradata) { // header not finalized yet
-                av_bprintf(&header, "%s", line);
+                av_bprintf(&header, "%s\n", line);
                 if (!strncmp(line, "[END INFORMATION]", 17) || !strncmp(line, "[SUBTITLE]", 10)) {
                     /* end of header */
                     res = avpriv_bprint_to_extradata(st->codec, &header);
@@ -116,29 +121,35 @@ static int subviewer_read_header(AVFormatContext *s)
                         i++;
                     while (line[i] == ' ')
                         i++;
-                    while (j < sizeof(value) - 1 && line[i] && !strchr("]\r\n", line[i]))
+                    while (j < sizeof(value) - 1 && line[i] && line[i] != ']')
                         value[j++] = line[i++];
                     value[j] = 0;
 
                     av_dict_set(&s->metadata, key, value, 0);
                 }
             }
-        } else {
-            int64_t pts_start = AV_NOPTS_VALUE;
-            int duration = -1;
-            int timed_line = !read_ts(line, &pts_start, &duration);
-            AVPacket *sub;
-
-            sub = ff_subtitles_queue_insert(&subviewer->q, line, len, !timed_line);
+        } else if (read_ts(line, &pts_start, &duration) >= 0) {
+            new_event = 1;
+            pos = avio_tell(s->pb);
+        } else if (*line) {
+            if (!new_event) {
+                sub = ff_subtitles_queue_insert(&subviewer->q, "\n", 1, 1);
+                if (!sub) {
+                    res = AVERROR(ENOMEM);
+                    goto end;
+                }
+            }
+            sub = ff_subtitles_queue_insert(&subviewer->q, line, strlen(line), !new_event);
             if (!sub) {
                 res = AVERROR(ENOMEM);
                 goto end;
             }
-            if (timed_line) {
+            if (new_event) {
                 sub->pos = pos;
                 sub->pts = pts_start;
                 sub->duration = duration;
             }
+            new_event = 0;
         }
     }
 

libavformat/version.h

@@ -31,7 +31,7 @@
 
 #define LIBAVFORMAT_VERSION_MAJOR 54
 #define LIBAVFORMAT_VERSION_MINOR 59
-#define LIBAVFORMAT_VERSION_MICRO 100
+#define LIBAVFORMAT_VERSION_MICRO 101
 
 #define LIBAVFORMAT_VERSION_INT AV_VERSION_INT(LIBAVFORMAT_VERSION_MAJOR, \
                                                LIBAVFORMAT_VERSION_MINOR, \

tests/ref/fate/sub-subviewer

@@ -1 +1 @@
-303c25863d2283928c19db58a53c93e2
+aef995d49af4517b40589b72cfa918f7