compositor: Add public interface support for client-requested idle inhibition

Signed-off-by: Bryce Harrington <bryce@osg.samsung.com>

v5: Improve comments
diff --git a/libweston/compositor.c b/libweston/compositor.c
index 7f92288..92f74aa 100644
--- a/libweston/compositor.c
+++ b/libweston/compositor.c
@@ -51,6 +51,8 @@
 #include <time.h>
 #include <errno.h>
 
+#include <idle-inhibit-unstable-v1-server-protocol.h>
+
 #include "timeline.h"
 
 #include "compositor.h"
@@ -4723,6 +4725,88 @@
 				       compositor, NULL);
 }
 
+struct weston_idle_inhibitor {
+	struct weston_surface *surface;
+};
+
+static void
+destroy_idle_inhibitor(struct wl_resource *resource)
+{
+	struct weston_idle_inhibitor *inhibitor = wl_resource_get_user_data(resource);
+
+	inhibitor->surface = NULL;
+	free(inhibitor);
+}
+
+static void
+idle_inhibitor_destroy(struct wl_client *client, struct wl_resource *resource)
+{
+	struct weston_idle_inhibitor *inhibitor = wl_resource_get_user_data(resource);
+
+	assert(inhibitor);
+
+	inhibitor->surface->inhibit_idling = false;
+}
+
+static const struct zwp_idle_inhibitor_v1_interface idle_inhibitor_interface = {
+	idle_inhibitor_destroy
+};
+
+static void
+idle_inhibit_manager_destroy(struct wl_client *client, struct wl_resource *resource)
+{
+}
+
+static void
+idle_inhibit_manager_create_inhibitor(struct wl_client *client, struct wl_resource *resource,
+				      uint32_t id, struct wl_resource *surface_resource)
+{
+	struct weston_surface *surface = wl_resource_get_user_data(surface_resource);
+	struct weston_idle_inhibitor *inhibitor;
+	struct wl_resource *cr;
+
+	cr = wl_resource_create(client, &zwp_idle_inhibitor_v1_interface,
+				wl_resource_get_version(resource), id);
+	if (cr == NULL) {
+		wl_client_post_no_memory(client);
+		return;
+	}
+
+	inhibitor = zalloc(sizeof *inhibitor);
+	if (inhibitor == NULL) {
+		wl_client_post_no_memory(client);
+		return;
+	}
+
+	inhibitor->surface = surface;
+	inhibitor->surface->inhibit_idling = true;
+
+	wl_resource_set_implementation(cr, &idle_inhibitor_interface,
+				       inhibitor, destroy_idle_inhibitor);
+}
+
+static const struct zwp_idle_inhibit_manager_v1_interface idle_inhibit_manager_interface = {
+	idle_inhibit_manager_destroy,
+	idle_inhibit_manager_create_inhibitor
+};
+
+static void
+bind_idle_inhibit_manager(struct wl_client *client,
+			  void *data, uint32_t version, uint32_t id)
+{
+	struct wl_resource *resource;
+
+	resource = wl_resource_create(client, &zwp_idle_inhibit_manager_v1_interface,
+				      version, id);
+	if (resource == NULL) {
+		wl_client_post_no_memory(client);
+		return;
+	}
+
+	wl_resource_set_implementation(resource, &idle_inhibit_manager_interface,
+				       NULL, NULL);
+}
+
 WL_EXPORT int
 weston_environment_get_fd(const char *env)
 {
@@ -4818,6 +4902,10 @@
 	if (weston_input_init(ec) != 0)
 		goto fail;
 
+	if (!wl_global_create(ec->wl_display, &zwp_idle_inhibit_manager_v1_interface, 1,
+			      ec, bind_idle_inhibit_manager))
+		goto fail;
+
 	wl_list_init(&ec->view_list);
 	wl_list_init(&ec->plane_list);
 	wl_list_init(&ec->layer_list);