Got simple working without keyboard input

examples/simple.c

@@ -1,4 +1,4 @@
-#define _POSIX_C_SOURCE 199309L
+#define _POSIX_C_SOURCE 200112L
 #include <GLES2/gl2.h>
 #include <inttypes.h>
 #include <stdio.h>
@@ -11,19 +11,30 @@
 #include <wlr/types/wlr_output.h>
 #include <wlr/util/log.h>
 #include <xkbcommon/xkbcommon.h>
-#include "support/shared.h"
 
 struct sample_state {
+	struct wl_listener new_output;
+	struct timespec last_frame;
 	float color[3];
 	int dec;
 };
 
-void handle_output_frame(struct output_state *output, struct timespec *ts) {
-	struct compositor_state *state = output->compositor;
-	struct sample_state *sample = state->data;
+struct sample_output {
+	struct sample_state *sample;
+	struct wlr_output *output;
+	struct wl_listener frame;
+	struct wl_listener destroy;
+};
+
+
+void output_frame_notify(struct wl_listener *listener, void *data) {
+	struct sample_output *sample_output = wl_container_of(listener, sample_output, frame);
+	struct sample_state *sample = sample_output->sample;
+	struct timespec now;
+	clock_gettime(CLOCK_MONOTONIC, &now);
 
-	long ms = (ts->tv_sec - state->last_frame.tv_sec) * 1000 +
-		(ts->tv_nsec - state->last_frame.tv_nsec) / 1000000;
+	long ms = (now.tv_sec - sample->last_frame.tv_sec) * 1000 +
+		(now.tv_nsec - sample->last_frame.tv_nsec) / 1000000;
 	int inc = (sample->dec + 1) % 3;
 
 	sample->color[inc] += ms / 2000.0f;
@@ -35,12 +46,31 @@ void handle_output_frame(struct output_state *output, struct timespec *ts) {
 		sample->dec = inc;
 	}
 
-	wlr_output_make_current(output->output, NULL);
+	wlr_output_make_current(sample_output->output, NULL);
 
 	glClearColor(sample->color[0], sample->color[1], sample->color[2], 1.0);
 	glClear(GL_COLOR_BUFFER_BIT);
 
-	wlr_output_swap_buffers(output->output, NULL, NULL);
+	wlr_output_swap_buffers(sample_output->output, NULL, NULL);
+	sample->last_frame = now;
+}
+
+void output_remove_notify(struct wl_listener *listener, void *data) {
+	struct sample_output *sample_output = wl_container_of(listener, sample_output, destroy);
+	wl_list_remove(&sample_output->frame.link);
+	free(sample_output);
+}
+
+void new_output_notify(struct wl_listener *listener, void *data) {
+	struct wlr_output *output = data;
+	struct sample_state *sample = wl_container_of(listener, sample, new_output);
+	struct sample_output *sample_output = calloc(1, sizeof(struct sample_output));
+	sample_output->output = output;
+	sample_output->sample = sample;
+	wl_signal_add(&output->events.frame, &sample_output->frame);
+	sample_output->frame.notify = output_frame_notify;
+	wl_signal_add(&output->events.destroy, &sample_output->destroy);
+	sample_output->destroy.notify = output_remove_notify;
 }
 
 int main() {
@@ -48,17 +78,28 @@ int main() {
 	struct sample_state state = {
 		.color = { 1.0, 0.0, 0.0 },
 		.dec = 0,
+		.last_frame = { 0 }
 	};
-	struct compositor_state compositor = { 0,
-		.data = &state,
-		.output_frame_cb = handle_output_frame,
-	};
-	compositor_init(&compositor);
-	if (!wlr_backend_start(compositor.backend)) {
+	struct wl_display *display = wl_display_create();
+	struct wlr_backend *wlr = wlr_backend_autocreate(display);
+	if (!wlr) {
+		exit(1);
+	}
+	wl_signal_add(&wlr->events.new_output, &state.new_output);
+	state.new_output.notify = new_output_notify;
+	clock_gettime(CLOCK_MONOTONIC, &state.last_frame);
+	const char *socket = wl_display_add_socket_auto(display);
+	if (!socket) {
+		wlr_log_errno(L_ERROR, "Unable to open wayland socket");
+		wlr_backend_destroy(wlr);
+		exit(1);
+	}
+	setenv("_WAYLAND_DISPLAY", socket, true);
+	if (!wlr_backend_start(wlr)) {
 		wlr_log(L_ERROR, "Failed to start backend");
-		wlr_backend_destroy(compositor.backend);
+		wlr_backend_destroy(wlr);
 		exit(1);
 	}
-	wl_display_run(compositor.display);
-	compositor_fini(&compositor);
+	wl_display_run(display);
+	wl_display_destroy(display);
 }