add an XDG friendly way of finding app-specific datafiles

3 files changed, 109 insertions, 0 deletions

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index fb8ffef..b68619c 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -10,6 +10,7 @@ endif()
 # handwritten sources
 set(SERVICE_MANUAL_SOURCES
     brightness.c
+    datafiles.c
     device-provider-mock.c
     device-provider-upower.c
     device-provider.c
diff --git a/src/datafiles.c b/src/datafiles.c
new file mode 100644
index 0000000..dba8048
--- /dev/null
+++ b/src/datafiles.c
@@ -0,0 +1,71 @@
+/*
+ * Copyright 2015 Canonical Ltd.
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 3, as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranties of
+ * MERCHANTABILITY, SATISFACTORY QUALITY, or FITNESS FOR A PARTICULAR
+ * PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors:
+ *   Charles Kerr <charles.kerr@canonical.com>
+ */
+
+#include "datafiles.h"
+
+static const gchar*
+get_directory_prefix_for_type (DatafileType type)
+{
+  switch (type)
+    {
+      case DATAFILE_TYPE_SOUND:
+        return "sounds";
+
+      default:
+        g_critical("unknown type");
+        return "";
+    }
+}
+
+static gchar*
+test_directory_for_file(const char* dir, DatafileType type, const char* basename)
+{
+  gchar* filename = g_build_filename(dir,
+                                     GETTEXT_PACKAGE,
+                                     get_directory_prefix_for_type(type),
+                                     basename,
+                                     NULL);
+
+  g_debug("looking for \"%s\" at \"%s\"", basename, filename);
+  if (g_file_test(filename, G_FILE_TEST_EXISTS))
+    return filename;
+
+  g_free(filename);
+  return NULL;
+}
+
+gchar*
+datafile_find(DatafileType type, const char * basename)
+{
+  gchar * filename;
+  const gchar * user_data_dir;
+  const gchar * const * system_data_dirs;
+  gsize i;
+
+  user_data_dir = g_get_user_data_dir();
+  if ((filename = test_directory_for_file(user_data_dir, type, basename)))
+    return filename;
+  
+  system_data_dirs = g_get_system_data_dirs();
+  for (i=0; system_data_dirs && system_data_dirs[i]; ++i)
+    if ((filename = test_directory_for_file(system_data_dirs[i], type, basename)))
+      return filename;
+
+  return NULL;
+}
diff --git a/src/datafiles.h b/src/datafiles.h
new file mode 100644
index 0000000..f624b9c
--- /dev/null
+++ b/src/datafiles.h
@@ -0,0 +1,37 @@
+/*
+ * Copyright 2015 Canonical Ltd.
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 3, as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranties of
+ * MERCHANTABILITY, SATISFACTORY QUALITY, or FITNESS FOR A PARTICULAR
+ * PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors:
+ *   Charles Kerr <charles.kerr@canonical.com>
+ */
+
+#ifndef __INDICATOR_POWER_DATAFILES_H__
+#define __INDICATOR_POWER_DATAFILES_H__
+
+#include <gio/gio.h>
+
+G_BEGIN_DECLS
+
+typedef enum 
+{
+  DATAFILE_TYPE_SOUND
+}
+DatafileType;
+
+gchar* datafile_find(DatafileType type, const char * basename);
+
+G_END_DECLS
+
+#endif /* __INDICATOR_POWER_DATAFILES_H__ */