2 files changed, 294 insertions, 0 deletions
diff --git a/examples/meson.build b/examples/meson.build
index 6ec40843..a29a3310 100644
--- a/examples/meson.build
+++ b/examples/meson.build
@@ -22,3 +22,9 @@ executable(
 	dependencies: wlroots,
 	link_with: lib_shared,
 )
+
+executable(
+	'screenshot',
+	'screenshot.c',
+	dependencies: [wayland_client, wlr_protos],
+)
diff --git a/examples/screenshot.c b/examples/screenshot.c
new file mode 100644
index 00000000..95af49ca
--- /dev/null
+++ b/examples/screenshot.c
@@ -0,0 +1,288 @@
+/*
+ * Copyright © 2008 Kristian Høgsberg
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#define _XOPEN_SOURCE 700
+#define _POSIX_C_SOURCE 199309L
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <sys/wait.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <wayland-client.h>
+#include <limits.h>
+#include <sys/param.h>
+#include <screenshooter-client-protocol.h>
+#include "../backend/wayland/os-compatibility.c"
+
+static struct wl_shm *shm = NULL;
+static struct orbital_screenshooter *screenshooter = NULL;
+static struct wl_list output_list;
+int min_x, min_y, max_x, max_y;
+int buffer_copy_done;
+
+struct screenshooter_output {
+	struct wl_output *output;
+	struct wl_buffer *buffer;
+	int width, height, offset_x, offset_y;
+	void *data;
+	struct wl_list link;
+};
+
+static void output_handle_geometry(void *data, struct wl_output *wl_output,
+		int x, int y, int physical_width, int physical_height, int subpixel,
+		const char *make, const char *model, int transform) {
+	struct screenshooter_output *output = wl_output_get_user_data(wl_output);
+
+	if (wl_output == output->output) {
+		output->offset_x = x;
+		output->offset_y = y;
+	}
+}
+
+static void output_handle_mode(void *data, struct wl_output *wl_output,
+		uint32_t flags, int width, int height, int refresh) {
+	struct screenshooter_output *output = wl_output_get_user_data(wl_output);
+
+	if (wl_output == output->output && (flags & WL_OUTPUT_MODE_CURRENT)) {
+		output->width = width;
+		output->height = height;
+	}
+}
+
+static void output_handle_done(void *data, struct wl_output *wl_output) {
+
+}
+
+static const struct wl_output_listener output_listener = {
+	.geometry = output_handle_geometry,
+	.mode = output_handle_mode,
+	.done = output_handle_done,
+};
+
+static void screenshot_done(void *data, struct orbital_screenshot *screenshot) {
+	buffer_copy_done = 1;
+}
+
+static const struct orbital_screenshot_listener screenshot_listener = {
+	.done = screenshot_done,
+};
+
+static void handle_global(void *data, struct wl_registry *registry,
+		uint32_t name, const char *interface, uint32_t version) {
+	static struct screenshooter_output *output;
+
+	if (strcmp(interface, "wl_output") == 0) {
+		output = calloc(1, sizeof *output);
+		output->output = wl_registry_bind(registry, name, &wl_output_interface,
+			1);
+		wl_list_insert(&output_list, &output->link);
+		wl_output_add_listener(output->output, &output_listener, output);
+	} else if (strcmp(interface, "wl_shm") == 0) {
+		shm = wl_registry_bind(registry, name, &wl_shm_interface, 1);
+	} else if (strcmp(interface, "orbital_screenshooter") == 0) {
+		screenshooter = wl_registry_bind(registry, name,
+			&orbital_screenshooter_interface, 1);
+	}
+}
+
+static void handle_global_remove(void *data, struct wl_registry *registry,
+		uint32_t name) {
+	// Unimplemented
+}
+
+static const struct wl_registry_listener registry_listener = {
+	.global = handle_global,
+	.global_remove = handle_global_remove,
+};
+
+static struct wl_buffer *create_shm_buffer(int width, int height,
+		void **data_out) {
+	int stride = width * 4;
+	int size = stride * height;
+
+	int fd = os_create_anonymous_file(size);
+	if (fd < 0) {
+		fprintf(stderr, "creating a buffer file for %d B failed: %m\n", size);
+		return NULL;
+	}
+
+	void *data = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+	if (data == MAP_FAILED) {
+		fprintf(stderr, "mmap failed: %m\n");
+		close(fd);
+		return NULL;
+	}
+
+	struct wl_shm_pool *pool = wl_shm_create_pool(shm, fd, size);
+	close(fd);
+	struct wl_buffer *buffer = wl_shm_pool_create_buffer(pool, 0, width, height,
+		stride, WL_SHM_FORMAT_XRGB8888);
+	wl_shm_pool_destroy(pool);
+
+	*data_out = data;
+
+	return buffer;
+}
+
+static void argb_to_rgba(uint32_t *data, size_t height, size_t stride) {
+	size_t n = height*stride/4;
+	for (size_t i = 0; i < n; ++i) {
+		uint32_t v = data[i];
+		uint32_t rgb = v & 0x00ffffff;
+		uint32_t a = (v & 0xff000000) >> 24;
+		data[i] = (rgb << 8) | a;
+	}
+}
+
+static void write_image(const char *filename, int width, int height) {
+	int buffer_stride = width * 4;
+
+	void *data = calloc(1, buffer_stride * height);
+	if (!data) {
+		return;
+	}
+
+	struct screenshooter_output *output, *next;
+	wl_list_for_each_safe(output, next, &output_list, link) {
+		int output_stride = output->width * 4;
+		void *s = output->data;
+		void *d = data + (output->offset_y - min_y) * buffer_stride +
+			(output->offset_x - min_x) * 4;
+
+		for (int i = 0; i < output->height; i++) {
+			memcpy(d, s, output_stride);
+			d += buffer_stride;
+			s += output_stride;
+		}
+
+		free(output);
+	}
+
+	argb_to_rgba(data, height, buffer_stride);
+
+	char size[10 + 1 + 10 + 2 + 1]; // int32_t are max 10 digits
+	sprintf(size, "%dx%d+0", width, height);
+
+	int fd[2];
+	pipe(fd);
+
+	pid_t child = fork();
+	if (child < 0) {
+		fprintf(stderr, "fork() failed\n");
+		exit(EXIT_FAILURE);
+	} else if (child != 0) {
+		close(fd[0]);
+		write(fd[1], data, buffer_stride * height);
+		close(fd[1]);
+		free(data);
+		waitpid(child, NULL, 0);
+	} else {
+		close(fd[1]);
+		if (dup2(fd[0], 0) != 0) {
+			fprintf(stderr, "cannot dup the pipe\n");
+			exit(EXIT_FAILURE);
+		}
+		close(fd[0]);
+		execlp("convert", "convert", "-depth", "8", "-size", size, "rgba:-",
+			"-alpha", "opaque", filename, NULL);
+		fprintf(stderr, "cannot execute convert\n");
+		exit(EXIT_FAILURE);
+	}
+}
+
+static int set_buffer_size(int *width, int *height) {
+	struct screenshooter_output *output;
+	min_x = min_y = INT_MAX;
+	max_x = max_y = INT_MIN;
+	int position = 0;
+
+	wl_list_for_each_reverse(output, &output_list, link) {
+		output->offset_x = position;
+		position += output->width;
+	}
+
+	wl_list_for_each(output, &output_list, link) {
+		min_x = MIN(min_x, output->offset_x);
+		min_y = MIN(min_y, output->offset_y);
+		max_x = MAX(max_x, output->offset_x + output->width);
+		max_y = MAX(max_y, output->offset_y + output->height);
+	}
+
+	if (max_x <= min_x || max_y <= min_y) {
+		return -1;
+	}
+
+	*width = max_x - min_x;
+	*height = max_y - min_y;
+
+	return 0;
+}
+
+int main(int argc, char *argv[]) {
+	struct wl_display * display = wl_display_connect(NULL);
+	if (display == NULL) {
+		fprintf(stderr, "failed to create display: %m\n");
+		return -1;
+	}
+
+	wl_list_init(&output_list);
+	struct wl_registry *registry = wl_display_get_registry(display);
+	wl_registry_add_listener(registry, &registry_listener, NULL);
+	wl_display_dispatch(display);
+	wl_display_roundtrip(display);
+
+	if (screenshooter == NULL) {
+		fprintf(stderr, "display doesn't support screenshooter\n");
+		return -1;
+	}
+
+	int width, height;
+	if (set_buffer_size(&width, &height)) {
+		fprintf(stderr, "cannot set buffer size\n");
+		return -1;
+	}
+
+	struct screenshooter_output *output;
+	wl_list_for_each(output, &output_list, link) {
+		if (output->width == 0 || output->height == 0) {
+			continue;
+		}
+
+		output->buffer = create_shm_buffer(output->width, output->height, &output->data);
+		if (output->buffer == NULL) {
+			return -1;
+		}
+		struct orbital_screenshot *screenshot = orbital_screenshooter_shoot(
+			screenshooter, output->output, output->buffer);
+		orbital_screenshot_add_listener(screenshot, &screenshot_listener, screenshot);
+		buffer_copy_done = 0;
+		while (!buffer_copy_done)
+			wl_display_roundtrip(display);
+	}
+
+	write_image("wayland-screenshot.png", width, height);
+	return EXIT_SUCCESS;
+}