crtc: Get/set gamma via helper struct

Instead of passing 4 arguments (red, green and blue arrays as well as a
size), always pass them together in a new struct MetaGammaLut. Makes
things slightly less tedious.

The KMS layer still has its own variant, but lets leave it as that for
now, to keep the KMS layer "below" the cross backend CRTC layer.

Part-of: <https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/2165>

1 files changed, 36 insertions, 22 deletions

diff --git a/src/backends/x11/meta-crtc-xrandr.c b/src/backends/x11/meta-crtc-xrandr.c
index 4fc579bed..c9104002f 100644
--- a/src/backends/x11/meta-crtc-xrandr.c
+++ b/src/backends/x11/meta-crtc-xrandr.c
@@ -297,38 +297,51 @@ meta_crtc_xrandr_new (MetaGpuXrandr      *gpu_xrandr,
   return crtc_xrandr;
 }
 
-static void
-meta_crtc_xrandr_get_gamma_lut (MetaCrtc        *crtc,
-                                size_t          *size,
-                                unsigned short **red,
-                                unsigned short **green,
-                                unsigned short **blue)
+static MetaGammaLut *
+meta_crtc_xrandr_get_gamma_lut (MetaCrtc *crtc)
+{
+  MetaGpu *gpu = meta_crtc_get_gpu (crtc);
+  MetaBackend *backend = meta_gpu_get_backend (gpu);
+  Display *xdisplay =
+    meta_backend_x11_get_xdisplay (META_BACKEND_X11 (backend));
+  XRRCrtcGamma *gamma;
+  MetaGammaLut *lut;
+
+  gamma = XRRGetCrtcGamma (xdisplay, (XID) meta_crtc_get_id (crtc));
+
+  lut = g_new0 (MetaGammaLut, 1);
+  lut->size = gamma->size;
+  lut->red = g_memdup2 (gamma->red, sizeof (unsigned short) * gamma->size);
+  lut->green = g_memdup2 (gamma->green, sizeof (unsigned short) * gamma->size);
+  lut->blue = g_memdup2 (gamma->blue, sizeof (unsigned short) * gamma->size);
+
+  XRRFreeGamma (gamma);
+
+  return lut;
+}
+
+static size_t
+meta_crtc_xrandr_get_gamma_lut_size (MetaCrtc *crtc)
 {
   MetaGpu *gpu = meta_crtc_get_gpu (crtc);
   MetaBackend *backend = meta_gpu_get_backend (gpu);
   Display *xdisplay =
     meta_backend_x11_get_xdisplay (META_BACKEND_X11 (backend));
   XRRCrtcGamma *gamma;
+  size_t size;
 
   gamma = XRRGetCrtcGamma (xdisplay, (XID) meta_crtc_get_id (crtc));
 
-  *size = gamma->size;
-  if (red)
-    *red = g_memdup2 (gamma->red, sizeof (unsigned short) * gamma->size);
-  if (green)
-    *green = g_memdup2 (gamma->green, sizeof (unsigned short) * gamma->size);
-  if (blue)
-    *blue = g_memdup2 (gamma->blue, sizeof (unsigned short) * gamma->size);
+  size = gamma->size;
 
   XRRFreeGamma (gamma);
+
+  return size;
 }
 
 static void
-meta_crtc_xrandr_set_gamma_lut (MetaCrtc       *crtc,
-                                size_t          size,
-                                unsigned short *red,
-                                unsigned short *green,
-                                unsigned short *blue)
+meta_crtc_xrandr_set_gamma_lut (MetaCrtc           *crtc,
+                                const MetaGammaLut *lut)
 {
   MetaGpu *gpu = meta_crtc_get_gpu (crtc);
   MetaBackend *backend = meta_gpu_get_backend (gpu);
@@ -336,10 +349,10 @@ meta_crtc_xrandr_set_gamma_lut (MetaCrtc       *crtc,
     meta_backend_x11_get_xdisplay (META_BACKEND_X11 (backend));
   XRRCrtcGamma *gamma;
 
-  gamma = XRRAllocGamma (size);
-  memcpy (gamma->red, red, sizeof (unsigned short) * size);
-  memcpy (gamma->green, green, sizeof (unsigned short) * size);
-  memcpy (gamma->blue, blue, sizeof (unsigned short) * size);
+  gamma = XRRAllocGamma (lut->size);
+  memcpy (gamma->red, lut->red, sizeof (uint16_t) * lut->size);
+  memcpy (gamma->green, lut->green, sizeof (uint16_t) * lut->size);
+  memcpy (gamma->blue, lut->blue, sizeof (uint16_t) * lut->size);
 
   XRRSetCrtcGamma (xdisplay, (XID) meta_crtc_get_id (crtc), gamma);
 
@@ -356,6 +369,7 @@ meta_crtc_xrandr_class_init (MetaCrtcXrandrClass *klass)
 {
   MetaCrtcClass *crtc_class = META_CRTC_CLASS (klass);
 
+  crtc_class->get_gamma_lut_size = meta_crtc_xrandr_get_gamma_lut_size;
   crtc_class->get_gamma_lut = meta_crtc_xrandr_get_gamma_lut;
   crtc_class->set_gamma_lut = meta_crtc_xrandr_set_gamma_lut;
 }