lavf: Rewrite metadata printing from dump_metadata().

This code contained several bugs that mis-formated the output.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavformat/utils.c

@@ -3483,11 +3483,19 @@ static void dump_metadata(void *ctx, AVDictionary *m, const char *indent)
         av_log(ctx, AV_LOG_INFO, "%sMetadata:\n", indent);
         while((tag=av_dict_get(m, "", tag, AV_DICT_IGNORE_SUFFIX))) {
             if(strcmp("language", tag->key)){
+                const char *p = tag->value;
+                av_log(ctx, AV_LOG_INFO, "%s  %-16s: ", indent, tag->key);
+                while(*p) {
                     char tmp[256];
-                int i;
-                av_strlcpy(tmp, tag->value, sizeof(tmp));
-                for(i=0; i<strlen(tmp); i++) if(tmp[i]==0xd) tmp[i]=' ';
-                av_log(ctx, AV_LOG_INFO, "%s  %-16s: %s\n", indent, tag->key, tmp);
+                    size_t len = strcspn(p, "\xd\xa");
+                    av_strlcpy(tmp, p, FFMIN(sizeof(tmp), len+1));
+                    av_log(ctx, AV_LOG_INFO, "%s", tmp);
+                    p += len;
+                    if (*p == 0xd) av_log(ctx, AV_LOG_INFO, " ");
+                    if (*p == 0xa) av_log(ctx, AV_LOG_INFO, "\n%s  %-16s: ", indent, "");
+                    if (*p) p++;
+                }
+                av_log(ctx, AV_LOG_INFO, "\n");
             }
         }
     }