[gthumb] Fixed crash when saving images with comments

[Paolo Bacchilega <paobac src gnome org>]

commit c2840c325e20f6435fcaeef500552cbe4fd1595c
Author: Paolo Bacchilega <paobac src gnome org>
Date:   Tue Aug 24 13:44:22 2010 +0200

    Fixed crash when saving images with comments
    
    Set the corrent value type for each metadatum.

 .../exiv2_tools/gth-metadata-provider-exiv2.c      |   29 +++++++++++++++++--
 extensions/exiv2_tools/main.c                      |    1 +
 gthumb/gth-metadata.c                              |   18 ++++++++++++
 gthumb/gth-metadata.h                              |    1 +
 4 files changed, 46 insertions(+), 3 deletions(-)
---
diff --git a/extensions/exiv2_tools/gth-metadata-provider-exiv2.c b/extensions/exiv2_tools/gth-metadata-provider-exiv2.c
index 1181c77..6a41daa 100644
--- a/extensions/exiv2_tools/gth-metadata-provider-exiv2.c
+++ b/extensions/exiv2_tools/gth-metadata-provider-exiv2.c
@@ -140,14 +140,37 @@ gth_metadata_provider_exiv2_write (GthMetadataProvider   *self,
 			"Iptc::Application2::Headline",
 			NULL
 		};
+		const char *tags_to_update[] = {
+			"Exif::Photo::UserComment",
+			"Xmp::dc::description",
+			"Iptc::Application2::Caption",
+			NULL
+		};
 		int i;
 
 		for (i = 0; tags_to_remove[i] != NULL; i++)
 			g_file_info_remove_attribute (file_data->info, tags_to_remove[i]);
 
-		g_file_info_set_attribute_object (file_data->info, "Exif::Photo::UserComment", metadata);
-		g_file_info_set_attribute_object (file_data->info, "Xmp::dc::description", metadata);
-		g_file_info_set_attribute_object (file_data->info, "Iptc::Application2::Caption", metadata);
+		/* Remove the value type to use the default type for each field
+		 * as described in exiv2_tools/main.c */
+
+		g_object_set (metadata, "value-type", NULL, NULL);
+
+		for (i = 0; tags_to_update[i] != NULL; i++) {
+			GObject *orig_metadata;
+
+			orig_metadata = g_file_info_get_attribute_object (file_data->info, tags_to_update[i]);
+			if (orig_metadata != NULL) {
+				/* keep the original value type */
+
+				g_object_set (orig_metadata,
+					      "raw", gth_metadata_get_raw (GTH_METADATA (metadata)),
+					      "formatted", gth_metadata_get_formatted (GTH_METADATA (metadata)),
+					      NULL);
+			}
+			else
+				g_file_info_set_attribute_object (file_data->info, tags_to_update[i], metadata);
+		}
 	}
 
 	metadata = g_file_info_get_attribute_object (file_data->info, "general::title");
diff --git a/extensions/exiv2_tools/main.c b/extensions/exiv2_tools/main.c
index 23c775f..24f114e 100644
--- a/extensions/exiv2_tools/main.c
+++ b/extensions/exiv2_tools/main.c
@@ -145,6 +145,7 @@ GthMetadataInfo exiv2_metadata_info[] = {
 	{ "Exif::Photo::RelatedImageLength", NULL, "Exif::Versions", 9, NULL, GTH_METADATA_ALLOW_IN_PROPERTIES_VIEW },
 
 	{ "Exif::Photo::MakerNote", NULL, "Exif::Other", 0, NULL, GTH_METADATA_ALLOW_NOWHERE },
+	{ "Exif::Photo::UserComment", NULL, "Exif::Other", 1, "Ascii", GTH_METADATA_ALLOW_IN_PROPERTIES_VIEW },
 
 	{ "Xmp::dc::description", NULL, "Xmp::Embedded", 0, "XmpText", GTH_METADATA_ALLOW_IN_PROPERTIES_VIEW },
 	{ "Xmp::dc::title", NULL, "Xmp::Embedded", 0, "XmpText", GTH_METADATA_ALLOW_IN_PROPERTIES_VIEW },
diff --git a/gthumb/gth-metadata.c b/gthumb/gth-metadata.c
index c7e9d71..e51dcf8 100644
--- a/gthumb/gth-metadata.c
+++ b/gthumb/gth-metadata.c
@@ -244,6 +244,24 @@ gth_metadata_get_value_type (GthMetadata *metadata)
 }
 
 
+GthMetadata *
+gth_metadata_dup (GthMetadata *metadata)
+{
+	GthMetadata *new_metadata;
+
+	new_metadata = gth_metadata_new ();
+	g_object_set (new_metadata,
+		      "id", metadata->priv->id,
+		      "description", metadata->priv->description,
+		      "raw", metadata->priv->raw,
+		      "formatted", metadata->priv->formatted,
+		      "value-type", metadata->priv->value_type,
+		      NULL);
+
+	return new_metadata;
+}
+
+
 GthMetadataInfo *
 gth_metadata_info_dup (GthMetadataInfo *info)
 {
diff --git a/gthumb/gth-metadata.h b/gthumb/gth-metadata.h
index b532dc2..9f2f41a 100644
--- a/gthumb/gth-metadata.h
+++ b/gthumb/gth-metadata.h
@@ -77,6 +77,7 @@ const char *      gth_metadata_get_id          (GthMetadata     *metadata);
 const char *      gth_metadata_get_raw         (GthMetadata     *metadata);
 const char *      gth_metadata_get_formatted   (GthMetadata     *metadata);
 const char *      gth_metadata_get_value_type  (GthMetadata     *metadata);
+GthMetadata *     gth_metadata_dup             (GthMetadata     *metadata);
 GthMetadataInfo * gth_metadata_info_dup        (GthMetadataInfo *info);
 void              set_attribute_from_string    (GFileInfo       *info,
 						const char      *key,