[IconFetcher] Add some doxygen documentation

include/rofi-icon-fetcher.h

@@ -6,16 +6,47 @@
 #include <cairo.h>
 #include "nkutils-xdg-theme.h"
 
+/**
+ * @defgroup ICONFETCHER IconFetcher
+ * @ingroup HELPERS
+ *
+ * Small helper of to fetch icons. This makes use of the 'view' threadpool.
+ * @{
+ */
+
+/**
+ * Initialize the icon fetcher.
+ */
 void rofi_icon_fetcher_init ( void );
 
-
+/**
+ * Destroy and free the memory used by the icon fetcher.
+ */
 void rofi_icon_fetcher_destroy ( void );
 
 
+/**
+ * @param name The name of the icon to fetch.
+ * @param size The size of the icon to fetch.
+ *
+ * Query the icon-theme for icon with name and size.
+ * The returned icon will be the best match for the requested size, it should still be resized to the actual size.
+ *
+ * name can also be a full path, if prefixed with file://.
+ *
+ * @returns the uid identifying the request.
+ */
 uint32_t rofi_icon_fetcher_query ( const char *name, const int size );
 
 
+/**
+ * @param uid The unique id representing the matching request.
+ *
+ * If the surface is used, the user should reference the surface.
+ *
+ * @returns the surface with the icon, NULL when not found.
+ */
 cairo_surface_t * rofi_icon_fetcher_get ( const uint32_t uid );
 
-
+/* @} */
 #endif // ROFI_ICON_FETCHER_H