misc

Signed-off-by: Mattias Andrée <maandree@kth.se>

1 files changed, 43 insertions, 0 deletions

diff --git a/libgamma_w32_gdi_crtc_initialise.c b/libgamma_w32_gdi_crtc_initialise.c
new file mode 100644
index 0000000..7bd2218
--- /dev/null
+++ b/libgamma_w32_gdi_crtc_initialise.c
@@ -0,0 +1,43 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+
+
+
+/**
+ * Initialise an allocated CRTC state
+ * 
+ * @param   this       The CRTC state to initialise
+ * @param   partition  The partition state for the partition that the CRTC belongs to
+ * @param   crtc       The the index of the CRTC within the site
+ * @return             Zero on success, otherwise (negative) the value of an
+ *                     error identifier provided by this library
+ */
+int
+libgamma_w32_gdi_crtc_initialise(libgamma_crtc_state_t *restrict this,
+                                 libgamma_partition_state_t *restrict partition, size_t crtc)
+{
+	DISPLAY_DEVICE display;
+	HDC context;
+
+	(void) partition;
+
+	this->data = NULL;
+
+	/* Windows's API mandates this... */
+	display.cb = sizeof(DISPLAY_DEVICE);
+	/* Get identifier for selected CRTC */
+	if (!EnumDisplayDevices(NULL, (DWORD)crtc, &display, 0))
+		return LIBGAMMA_NO_SUCH_CRTC;
+	/* Check that the connector is enabled,
+	 * newer versions of Windows will always pass.
+	 * (According to w32's documentation, but that
+	 * that is a load of crap) */
+	if (!(display.StateFlags & DISPLAY_DEVICE_ACTIVE))
+		return LIBGAMMA_CONNECTOR_DISABLED;
+	/* Acquire CRTC connection. */
+	context = CreateDC(TEXT("DISPLAY"), display.DeviceName, NULL, NULL);
+	if (!context)
+		return LIBGAMMA_OPEN_CRTC_FAILED;
+	this->data = context;
+	return 0;
+}