add libgamma_is_method_available

Signed-off-by: Mattias Andrée <maandree@operamail.com>

2 files changed, 51 insertions, 0 deletions

diff --git a/src/libgamma-facade.c b/src/libgamma-facade.c
index ef5d369..c94d9e3 100644
--- a/src/libgamma-facade.c
+++ b/src/libgamma-facade.c
@@ -212,6 +212,48 @@ size_t libgamma_list_methods(int* restrict methods, size_t buf_size, int operati
 
 
 /**
+ * Check whether an adjustment method is available, non-existing (invalid) methods will be
+ * identified as not available under the rationale that the library may be out of date.
+ * 
+ * @param   method  The adjustment method.
+ * @return          Whether the adjustment method is available.
+ */
+int libgamma_is_method_available(int method)
+{
+#ifdef HAVE_NO_LIBGAMMA_METHODS
+  (void) methods;
+  return 0;
+#else
+  switch (method)
+    {
+#ifdef HAVE_LIBGAMMA_METHOD_DUMMY
+    case LIBGAMMA_METHOD_DUMMY:
+#endif
+#ifdef HAVE_LIBGAMMA_METHOD_X_RANDR
+    case LIBGAMMA_METHOD_X_RANDR:
+#endif
+#ifdef HAVE_LIBGAMMA_METHOD_X_VIDMODE
+    case LIBGAMMA_METHOD_X_VIDMODE:
+#endif
+#ifdef HAVE_LIBGAMMA_METHOD_LINUX_DRM
+    case LIBGAMMA_METHOD_LINUX_DRM:
+#endif
+#ifdef HAVE_LIBGAMMA_METHOD_W32_GDI
+    case LIBGAMMA_METHOD_W32_GDI:
+#endif
+#ifdef HAVE_LIBGAMMA_METHOD_QUARTZ_CORE_GRAPHICS
+    case LIBGAMMA_METHOD_QUARTZ_CORE_GRAPHICS:
+#endif
+      return 1;
+      
+    default:
+      return 0;
+    }
+#endif
+}
+
+
+/**
  * Return the capabilities of an adjustment method.
  * 
  * @param  this    The data structure to fill with the method's capabilities.
diff --git a/src/libgamma-facade.h b/src/libgamma-facade.h
index db5075b..fdf46ae 100644
--- a/src/libgamma-facade.h
+++ b/src/libgamma-facade.h
@@ -93,6 +93,15 @@ typedef double libgamma_gamma_rampsd_fun(double encoding);
 size_t libgamma_list_methods(int* restrict methods, size_t buf_size, int operation);
 
 /**
+ * Check whether an adjustment method is available, non-existing (invalid) methods will be
+ * identified as not available under the rationale that the library may be out of date.
+ * 
+ * @param   method  The adjustment method.
+ * @return          Whether the adjustment method is available.
+ */
+int libgamma_is_method_available(int method) __attribute__((const));
+
+/**
  * Return the capabilities of an adjustment method.
  * 
  * @param  this    The data structure to fill with the method's capabilities