jpeg-utils: Allow custom datetime format

The default locale datetime format string may not suit everyone, this
adds possibility to specify custom format. The format string should be
syntactically conforming to strftime(3).

6 files changed, 14 insertions, 2 deletions

diff --git a/sample/src/setup.xml b/sample/src/setup.xml
index 54bfb5b..f36b01b 100644
--- a/sample/src/setup.xml
+++ b/sample/src/setup.xml
@@ -72,6 +72,12 @@ And the second line.</add_copyright>
     <!--  ASCII encoding preferred.                                          -->
     <artist_name>John Doe</artist_name>
 
+    <!--  Specify datetime format according to strftime(3). Leave unspecified -->
+    <!--  for default format string according to current locale.              -->
+    <!--  Note that in travel photography in general it makes sense to always -->
+    <!--  show local time, omitting timezone.                                 -->
+<!--    <datetime format="%c" />  -->
+
     <!--  favicon support, the "type" attribute is optional,   --> 
     <!--  please alter it to the right icon MIME type          -->
     <!--    http://www.w3.org/2005/10/howto-favicon            -->
diff --git a/src/generators.c b/src/generators.c
index ed525cf..5ab5765 100644
--- a/src/generators.c
+++ b/src/generators.c
@@ -320,6 +320,8 @@ metadata_apply_overrides (ExifData *exif_data,
   exif_data->thumbnail_crop_hint = get_prop_int (items, item, PROP_THUMB_CROP_HINT, CROP_HINT_UNDEFINED);
 
   exif_data->shave_amount = get_prop_int (items, item, PROP_SHAVE_AMOUNT, 0);
+
+  exif_data->datetime_format = setup->datetime_format;
 }
 
 static char *
diff --git a/src/jpeg-utils.cpp b/src/jpeg-utils.cpp
index e9e1e65..61aeebd 100644
--- a/src/jpeg-utils.cpp
+++ b/src/jpeg-utils.cpp
@@ -289,7 +289,7 @@ get_exif_data_fixed (ExifData *exif, const gchar *key)
           if (exif->override_datetime != (time_t) -1) {
             tt = (struct tm *) g_malloc0 (sizeof (struct tm));
             localtime_r (&exif->override_datetime, tt);
-            if (strftime (&conv[0], sizeof (conv), "%c", tt))
+            if (strftime (&conv[0], sizeof (conv), exif->datetime_format ? exif->datetime_format : "%c", tt))
               res = g_strdup (&conv[0]);
           }
 
@@ -297,7 +297,7 @@ get_exif_data_fixed (ExifData *exif, const gchar *key)
             tt = parse_exif_date (val);
             if (tt) {
               shift_time (tt, exif->timezone_shift);
-              if (strftime (&conv[0], sizeof (conv), "%c", tt))
+              if (strftime (&conv[0], sizeof (conv), exif->datetime_format ? exif->datetime_format : "%c", tt))
                 res = g_strdup (&conv[0]);
             }
           }
diff --git a/src/jpeg-utils.h b/src/jpeg-utils.h
index b4ead79..767320a 100644
--- a/src/jpeg-utils.h
+++ b/src/jpeg-utils.h
@@ -58,6 +58,7 @@ typedef struct {
   double override_focal_length;
   gchar *override_artist_name;
   gchar *external_exif_data;
+  const gchar *datetime_format;
   TCropStyle thumbnail_crop_style;
   TCropHint thumbnail_crop_hint;
   int shave_amount;
diff --git a/src/setup.c b/src/setup.c
index cf23044..85c7326 100644
--- a/src/setup.c
+++ b/src/setup.c
@@ -113,6 +113,7 @@ parse_setup_xml (const gchar *filename)
   setup->site_title = xml_file_get_node_attribute (xml, "/gallery_setup/meta/site", "title");
   setup->add_copyright = xml_file_get_node_value (xml, "/gallery_setup/meta/add_copyright/text()");
   setup->meta_artist_name = xml_file_get_node_value (xml, "/gallery_setup/meta/artist_name/text()");
+  setup->datetime_format = xml_file_get_node_attribute (xml, "/gallery_setup/meta/datetime", "format");
   setup->favicon_file = xml_file_get_node_value (xml, "/gallery_setup/meta/favicon/text()");
   setup->favicon_type = xml_file_get_node_attribute (xml, "/gallery_setup/meta/favicon", "type");
 
@@ -685,6 +686,7 @@ free_setup_data (TGallerySetup *setup)
     g_free (setup->site_title);
     g_free (setup->add_copyright);
     g_free (setup->meta_artist_name);
+    g_free (setup->datetime_format);
     g_free (setup->favicon_file);
     g_free (setup->favicon_type);
     g_free (setup->feed_filename);
diff --git a/src/setup.h b/src/setup.h
index 730c035..009566a 100644
--- a/src/setup.h
+++ b/src/setup.h
@@ -74,6 +74,7 @@ typedef struct {
   gchar *site_title;
   gchar *add_copyright;
   gchar *meta_artist_name;
+  gchar *datetime_format;
   gchar *favicon_file;
   gchar *favicon_type;