From 77353dad21203d3007d9588ae35ef818a0103fa8 Mon Sep 17 00:00:00 2001
From: Thiago Santos <thiago.sousa.santos@collabora.com>
Date: Thu, 22 Dec 2011 07:53:39 -0300
Subject: [PATCH] tag: xmp: Keep compatibility with our old generated xmp

We used to add a trailing \n to the end of generated xmp packets.
Windows viewer was unhappy with it and we fixed it in
96d2120c2bb0b29e1849098198f5fbef81939cdd

The problem is that this caused xmp generated before this fix
to not be recognized and parsed anymore. This patch makes it
recognize xmp with the trailing \n and without, fixing the
regression. Also adds tests for it.
---
 gst-libs/gst/tag/gstxmptag.c |  5 ++-
 tests/check/libs/tag.c       | 62 +++++++++++++++++++++---------------
 2 files changed, 41 insertions(+), 26 deletions(-)

diff --git a/gst-libs/gst/tag/gstxmptag.c b/gst-libs/gst/tag/gstxmptag.c
index abe359724e..1fb7f3945b 100644
--- a/gst-libs/gst/tag/gstxmptag.c
+++ b/gst-libs/gst/tag/gstxmptag.c
@@ -1317,7 +1317,10 @@ gst_tag_list_from_xmp_buffer (const GstBuffer * buffer)
   if (*xp1 != '>')
     goto missing_header;
 
-  max_ft_len = 1 + strlen ("<?xpacket end=\".\"?>");
+  /* Use 2 here to count for an extra trailing \n that was added
+   * in old versions, this makes it able to parse xmp packets with
+   * and without this trailing char */
+  max_ft_len = 2 + strlen ("<?xpacket end=\".\"?>");
   if (len < max_ft_len)
     goto missing_footer;
 
diff --git a/tests/check/libs/tag.c b/tests/check/libs/tag.c
index 17401c37ee..db5932360a 100644
--- a/tests/check/libs/tag.c
+++ b/tests/check/libs/tag.c
@@ -975,13 +975,21 @@ GST_START_TEST (test_xmp_parsing)
 {
   GstTagList *list;
   GstBuffer *buf;
-  guint i, result_size;
+  guint i, j, result_size;
   gchar *text;
   const gchar *xmp_header =
       "<?xpacket begin=\"\xEF\xBB\xBF\" id=\"W5M0MpCehiHzreSzNTczkc9d\"?>"
       "<x:xmpmeta xmlns:x=\"adobe:ns:meta/\" x:xmptk=\"GStreamer\">"
       "<rdf:RDF xmlns:rdf=\"http://www.w3.org/1999/02/22-rdf-syntax-ns#\" xmlns:dc=\"http://purl.org/dc/elements/1.1/\">";
-  const gchar *xmp_footer = "</rdf:RDF>" "</x:xmpmeta>" "<?xpacket end=\"r\"?>";
+
+  /* We used to write an extra trailing \n after the footer, keep compatibility
+   * with our old generated media by checking that it still can be parsed */
+  const gchar *xmp_footers[] = {
+    "</rdf:RDF>" "</x:xmpmeta>" "<?xpacket end=\"r\"?>",
+    "</rdf:RDF>" "</x:xmpmeta>" "<?xpacket end=\"r\"?>\n",
+    NULL
+  };
+
   struct
   {
     const gchar *xmp_data;
@@ -1003,36 +1011,40 @@ GST_START_TEST (test_xmp_parsing)
   /* test data */
   buf = gst_buffer_new ();
 
+  j = 0;
   i = 0;
-  while (test_data[i].xmp_data) {
-    GST_DEBUG ("trying test-data %u", i);
+  while (xmp_footers[j]) {
+    while (test_data[i].xmp_data) {
+      GST_DEBUG ("trying test-data %u", i);
 
-    text = g_strconcat (xmp_header, test_data[i].xmp_data, xmp_footer, NULL);
-    GST_BUFFER_DATA (buf) = (guint8 *) text;
-    GST_BUFFER_SIZE (buf) = strlen (text) + 1;
+      text =
+          g_strconcat (xmp_header, test_data[i].xmp_data, xmp_footers[j], NULL);
+      GST_BUFFER_DATA (buf) = (guint8 *) text;
+      GST_BUFFER_SIZE (buf) = strlen (text) + 1;
 
+      list = gst_tag_list_from_xmp_buffer (buf);
+      if (test_data[i].result_size >= 0) {
+        fail_unless (list != NULL);
 
-    list = gst_tag_list_from_xmp_buffer (buf);
-    if (test_data[i].result_size >= 0) {
-      fail_unless (list != NULL);
+        result_size = gst_structure_n_fields ((GstStructure *) list);
+        fail_unless (result_size == test_data[i].result_size);
 
-      result_size = gst_structure_n_fields ((GstStructure *) list);
-      fail_unless (result_size == test_data[i].result_size);
-
-      /* check the taglist content */
-      switch (test_data[i].result_test) {
-        case 0:
-          ASSERT_TAG_LIST_HAS_STRING (list, "description", "test");
-          break;
-        default:
-          break;
+        /* check the taglist content */
+        switch (test_data[i].result_test) {
+          case 0:
+            ASSERT_TAG_LIST_HAS_STRING (list, "description", "test");
+            break;
+          default:
+            break;
+        }
       }
-    }
-    if (list)
-      gst_tag_list_free (list);
+      if (list)
+        gst_tag_list_free (list);
 
-    g_free (text);
-    i++;
+      g_free (text);
+      i++;
+    }
+    j++;
   }
 
   gst_buffer_unref (buf);