[client] wayland: keep track of wl_output scale information

This will later be used to control the size of the underlying EGL buffers
in order to handle high DPI.

client/displayservers/Wayland/CMakeLists.txt

@@ -15,6 +15,7 @@ add_library(displayserver_Wayland STATIC
 	gl.c
 	idle.c
 	input.c
+	output.c
 	poll.c
 	state.c
 	registry.c

client/displayservers/Wayland/output.c

@@ -0,0 +1,126 @@
+/*
+Looking Glass - KVM FrameRelay (KVMFR) Client
+Copyright (C) 2021 Guanzhong Chen (quantum2048@gmail.com)
+Copyright (C) 2021 Tudor Brindus (contact@tbrindus.ca)
+https://looking-glass.io
+
+This program is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free Software
+Foundation; either version 2 of the License, or (at your option) any later
+version.
+
+This program is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY 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, write to the Free Software Foundation, Inc., 59 Temple
+Place, Suite 330, Boston, MA 02111-1307 USA
+*/
+
+#include "wayland.h"
+
+#include <stdbool.h>
+#include <string.h>
+
+#include <wayland-client.h>
+
+#include "common/debug.h"
+
+static void outputGeometryHandler(void * data, struct wl_output * output, int32_t x, int32_t y,
+    int32_t physical_width, int32_t physical_height, int32_t subpixel, const char * make,
+    const char * model, int32_t output_transform)
+{
+  // Do nothing.
+}
+
+static void outputModeHandler(void * data, struct wl_output * wl_output, uint32_t flags,
+    int32_t width, int32_t height, int32_t refresh)
+{
+  // Do nothing.
+}
+
+static void outputDoneHandler(void * data, struct wl_output * output)
+{
+  // Do nothing.
+}
+
+static void outputScaleHandler(void * opaque, struct wl_output * output, int32_t scale)
+{
+  struct WaylandOutput * node = opaque;
+  node->scale = scale;
+}
+
+static const struct wl_output_listener outputListener = {
+  .geometry = outputGeometryHandler,
+  .mode = outputModeHandler,
+  .done = outputDoneHandler,
+  .scale = outputScaleHandler,
+};
+
+bool waylandOutputInit(void)
+{
+  wl_list_init(&wlWm.outputs);
+  return true;
+}
+
+void waylandOutputFree(void)
+{
+  struct WaylandOutput * node;
+  struct WaylandOutput * temp;
+  wl_list_for_each_safe(node, temp, &wlWm.outputs, link)
+  {
+    wl_output_release(node->output);
+    wl_list_remove(&node->link);
+    free(node);
+  }
+}
+
+void waylandOutputBind(uint32_t name)
+{
+  struct WaylandOutput * node = malloc(sizeof(struct WaylandOutput));
+  if (!node)
+    return;
+
+  node->name   = name;
+  node->scale  = 0;
+  node->output = wl_registry_bind(wlWm.registry, name,
+      &wl_output_interface, 3);
+
+  if (!node->output)
+  {
+    DEBUG_ERROR("Failed to bind to wl_output %u\n", name);
+    free(node);
+    return;
+  }
+
+  wl_output_add_listener(node->output, &outputListener, node);
+  wl_list_insert(&wlWm.outputs, &node->link);
+}
+
+void waylandOutputTryUnbind(uint32_t name)
+{
+  struct WaylandOutput * node;
+
+  wl_list_for_each(node, &wlWm.outputs, link)
+  {
+    if (node->name == name)
+    {
+      wl_output_release(node->output);
+      wl_list_remove(&node->link);
+      free(node);
+      break;
+    }
+  }
+}
+
+int32_t waylandOutputGetScale(struct wl_output * output)
+{
+  struct WaylandOutput * node;
+
+  wl_list_for_each(node, &wlWm.outputs, link)
+    if (node->output == output)
+      return node->scale;
+  return 0;
+}
+

client/displayservers/Wayland/registry.c

@@ -30,7 +30,9 @@ Place, Suite 330, Boston, MA 02111-1307 USA
 static void registryGlobalHandler(void * data, struct wl_registry * registry,
     uint32_t name, const char * interface, uint32_t version)
 {
-  if (!strcmp(interface, wl_seat_interface.name) && !wlWm.seat)
+  if (!strcmp(interface, wl_output_interface.name))
+    waylandOutputBind(name);
+  else if (!strcmp(interface, wl_seat_interface.name) && !wlWm.seat)
     wlWm.seat = wl_registry_bind(wlWm.registry, name, &wl_seat_interface, 1);
   else if (!strcmp(interface, wl_shm_interface.name))
     wlWm.shm = wl_registry_bind(wlWm.registry, name, &wl_shm_interface, 1);
@@ -61,7 +63,7 @@ static void registryGlobalHandler(void * data, struct wl_registry * registry,
 static void registryGlobalRemoveHandler(void * data,
     struct wl_registry * registry, uint32_t name)
 {
-  // Do nothing.
+  waylandOutputTryUnbind(name);
 }
 
 static const struct wl_registry_listener registryListener = {

client/displayservers/Wayland/wayland.c

@@ -97,6 +97,9 @@ static bool waylandInit(const LG_DSInitParams params)
   if (!waylandPollInit())
     return false;
 
+  if (!waylandOutputInit())
+    return false;
+
   if (!waylandRegistryInit())
     return false;
 
@@ -139,6 +142,7 @@ static void waylandFree(void)
   waylandIdleFree();
   waylandWindowFree();
   waylandInputFree();
+  waylandOutputFree();
   waylandRegistryFree();
   wl_display_disconnect(wlWm.display);
 }

client/displayservers/Wayland/wayland.h

@@ -51,6 +51,14 @@ struct WaylandPoll
   struct wl_list link;
 };
 
+struct WaylandOutput
+{
+  uint32_t name;
+  int32_t scale;
+  struct wl_output * output;
+  struct wl_list link;
+};
+
 struct WaylandDSState
 {
   bool pointerGrabbed;
@@ -108,6 +116,8 @@ struct WaylandDSState
   struct zwp_idle_inhibit_manager_v1 * idleInhibitManager;
   struct zwp_idle_inhibitor_v1 * idleInhibitor;
 
+  struct wl_list outputs; // WaylandOutput::link
+
   struct wl_list poll; // WaylandPoll::link
   struct wl_list pollFree; // WaylandPoll::link
   LG_Lock pollLock;
@@ -200,6 +210,13 @@ void waylandUngrabPointer(void);
 void waylandRealignPointer(void);
 void waylandWarpPointer(int x, int y, bool exiting);
 
+// output module
+bool waylandOutputInit(void);
+void waylandOutputFree(void);
+void waylandOutputBind(uint32_t name);
+void waylandOutputTryUnbind(uint32_t name);
+int32_t waylandOutputGetScale(struct wl_output * output);
+
 // poll module
 bool waylandPollInit(void);
 void waylandWait(unsigned int time);