headless: port the headless backend to the new init api

refactor configuration API of headless-backend

Signed-off-by: Bryce Harrington <bryce@osg.samsung.com>
Reviewed-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>

v6:
  - Define version number in the header
  - Don't use leading underscores in header guards
  - Add stub config_init_to_defaults()
  - Allocate config on stack
  - Drop unused display_name parameter
  - Add error message when config is invalid
  - Install compositor-headless.h and list it in headless-backend sources
v5:
  - Update to current trunk
  - Fixed typo 'struct weston_wayland_backend_config'
  - Dropped unused variables
  - Dropped weston_headless_backend_config_create() in favor of
    directly zalloc'ing the object
  - Dropped weston_headless_backend_load() in favor of the more
    generalized load_backend_new().
  - Dropped typedef from header
  - Restored use of 'backend_init' entry point
  - Backend_init() takes a base weston_backend_config object
  - Renamed 'param' to 'config' in a few places for consistency
  - Renamed 'headless_options' variable to 'options for consistency
  - Version the base struct
  - Free config on error
  - Don't free config during backend_init normal operations
  - Adjust header ordering
  - Make header guard naming consistent with other headers
  - Light reformatting for code style and consistency with other
    backend config patches

Signed-off-by: Bryce Harrington <bryce@osg.samsung.com>
Reviewed-by: Giulio Camuffo <giuliocamuffo@gmail.com>
[Pekka: rebased to apply before drm and x11 backends]
[Pekka: squashed in the headless part of "Enforce destruction of all
backend config objects after initialization"]
Signed-off-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>

4 files changed, 126 insertions, 44 deletions

diff --git a/Makefile.am b/Makefile.am
index 9bed32c7..d3c3f71e 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -72,6 +72,7 @@ weston_SOURCES =					\
 	src/log.c					\
 	src/compositor.c				\
 	src/compositor.h				\
+	src/compositor-headless.h		\
 	src/input.c					\
 	src/data-device.c				\
 	src/screenshooter.c				\
@@ -208,6 +209,7 @@ westonincludedir = $(includedir)/weston
 westoninclude_HEADERS =				\
 	src/version.h				\
 	src/compositor.h			\
+	src/compositor-headless.h		\
 	src/timeline-object.h			\
 	shared/matrix.h				\
 	shared/config-parser.h			\
@@ -353,6 +355,7 @@ headless_backend_la_LIBADD = $(COMPOSITOR_LIBS) libshared.la
 headless_backend_la_CFLAGS = $(COMPOSITOR_CFLAGS) $(AM_CFLAGS)
 headless_backend_la_SOURCES = 			\
 	src/compositor-headless.c		\
+	src/compositor-headless.h		\
 	shared/helpers.h
 endif
 
diff --git a/src/compositor-headless.c b/src/compositor-headless.c
index 16b5c39d..ed6c48c4 100644
--- a/src/compositor-headless.c
+++ b/src/compositor-headless.c
@@ -31,33 +31,29 @@
 #include <sys/time.h>
 #include <stdbool.h>
 
-#include "shared/helpers.h"
 #include "compositor.h"
+#include "compositor-headless.h"
+#include "shared/helpers.h"
 #include "pixman-renderer.h"
 #include "presentation-time-server-protocol.h"
 
 struct headless_backend {
 	struct weston_backend base;
 	struct weston_compositor *compositor;
+
 	struct weston_seat fake_seat;
 	bool use_pixman;
 };
 
 struct headless_output {
 	struct weston_output base;
+
 	struct weston_mode mode;
 	struct wl_event_source *finish_frame_timer;
 	uint32_t *image_buf;
 	pixman_image_t *image;
 };
 
-struct headless_parameters {
-	int width;
-	int height;
-	int use_pixman;
-	uint32_t transform;
-};
-
 static void
 headless_output_start_repaint_loop(struct weston_output *output)
 {
@@ -120,7 +116,7 @@ headless_output_destroy(struct weston_output *output_base)
 
 static int
 headless_backend_create_output(struct headless_backend *b,
-			       struct headless_parameters *param)
+			       struct weston_headless_backend_config *config)
 {
 	struct weston_compositor *c = b->compositor;
 	struct headless_output *output;
@@ -132,15 +128,15 @@ headless_backend_create_output(struct headless_backend *b,
 
 	output->mode.flags =
 		WL_OUTPUT_MODE_CURRENT | WL_OUTPUT_MODE_PREFERRED;
-	output->mode.width = param->width;
-	output->mode.height = param->height;
+	output->mode.width = config->width;
+	output->mode.height = config->height;
 	output->mode.refresh = 60000;
 	wl_list_init(&output->base.mode_list);
 	wl_list_insert(&output->base.mode_list, &output->mode.link);
 
 	output->base.current_mode = &output->mode;
-	weston_output_init(&output->base, c, 0, 0, param->width,
-			   param->height, param->transform, 1);
+	weston_output_init(&output->base, c, 0, 0, config->width,
+			   config->height, config->transform, 1);
 
 	output->base.make = "weston";
 	output->base.model = "headless";
@@ -158,15 +154,15 @@ headless_backend_create_output(struct headless_backend *b,
 	output->base.switch_mode = NULL;
 
 	if (b->use_pixman) {
-		output->image_buf = malloc(param->width * param->height * 4);
+		output->image_buf = malloc(config->width * config->height * 4);
 		if (!output->image_buf)
 			return -1;
 
 		output->image = pixman_image_create_bits(PIXMAN_x8r8g8b8,
-							 param->width,
-							 param->height,
+							 config->width,
+							 config->height,
 							 output->image_buf,
-							 param->width * 4);
+							 config->width * 4);
 
 		if (pixman_renderer_output_create(&output->base) < 0)
 			return -1;
@@ -217,8 +213,7 @@ headless_destroy(struct weston_compositor *ec)
 
 static struct headless_backend *
 headless_backend_create(struct weston_compositor *compositor,
-			struct headless_parameters *param,
-			const char *display_name)
+			struct weston_headless_backend_config *config)
 {
 	struct headless_backend *b;
 
@@ -236,11 +231,11 @@ headless_backend_create(struct weston_compositor *compositor,
 	b->base.destroy = headless_destroy;
 	b->base.restore = headless_restore;
 
-	b->use_pixman = param->use_pixman;
+	b->use_pixman = config->use_pixman;
 	if (b->use_pixman) {
 		pixman_renderer_init(compositor);
 	}
-	if (headless_backend_create_output(b, param) < 0)
+	if (headless_backend_create_output(b, config) < 0)
 		goto err_input;
 
 	if (!b->use_pixman && noop_renderer_init(compositor) < 0)
@@ -257,36 +252,33 @@ err_free:
 	return NULL;
 }
 
+static void
+config_init_to_defaults(struct weston_headless_backend_config *config)
+{
+}
+
 WL_EXPORT int
 backend_init(struct weston_compositor *compositor,
 	     int *argc, char *argv[],
-	     struct weston_config *config,
+	     struct weston_config *wc,
 	     struct weston_backend_config *config_base)
 {
-	int width = 1024, height = 640;
-	char *display_name = NULL;
-	struct headless_parameters param = { 0, };
-	const char *transform = "normal";
 	struct headless_backend *b;
+	struct weston_headless_backend_config config = {{ 0, }};
 
-	const struct weston_option headless_options[] = {
-		{ WESTON_OPTION_INTEGER, "width", 0, &width },
-		{ WESTON_OPTION_INTEGER, "height", 0, &height },
-		{ WESTON_OPTION_BOOLEAN, "use-pixman", 0, &param.use_pixman },
-		{ WESTON_OPTION_STRING, "transform", 0, &transform },
-	};
-
-	parse_options(headless_options,
-		      ARRAY_LENGTH(headless_options), argc, argv);
-
-	param.width = width;
-	param.height = height;
+	if (config_base == NULL ||
+	    config_base->struct_version != WESTON_HEADLESS_BACKEND_CONFIG_VERSION ||
+	    config_base->struct_size > sizeof(struct weston_headless_backend_config)) {
+		weston_log("headless backend config structure is invalid\n");
+		return -1;
+	}
 
-	if (weston_parse_transform(transform, &param.transform) < 0)
-		weston_log("Invalid transform \"%s\"\n", transform);
+	config_init_to_defaults(&config);
+	memcpy(&config, config_base, config_base->struct_size);
 
-	b = headless_backend_create(compositor, &param, display_name);
+	b = headless_backend_create(compositor, &config);
 	if (b == NULL)
 		return -1;
+
 	return 0;
 }
diff --git a/src/compositor-headless.h b/src/compositor-headless.h
new file mode 100644
index 00000000..79f39c89
--- /dev/null
+++ b/src/compositor-headless.h
@@ -0,0 +1,53 @@
+/*
+ * Copyright © 2016 Benoit Gschwind
+ *
+ * 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.
+ */
+
+#ifndef WESTON_COMPOSITOR_HEADLESS_H
+#define WESTON_COMPOSITOR_HEADLESS_H
+
+#ifdef  __cplusplus
+extern "C" {
+#endif
+
+#include "compositor.h"
+
+#define WESTON_HEADLESS_BACKEND_CONFIG_VERSION 1
+
+struct weston_headless_backend_config {
+	struct weston_backend_config base;
+
+	int width;
+	int height;
+
+	/** Whether to use the pixman renderer instead of the OpenGL ES renderer. */
+	int use_pixman;
+
+	uint32_t transform;
+};
+
+#ifdef  __cplusplus
+}
+#endif
+
+#endif /* WESTON_COMPOSITOR_HEADLESS_H */
diff --git a/src/main.c b/src/main.c
index 6a708e37..fc97dd80 100644
--- a/src/main.c
+++ b/src/main.c
@@ -47,6 +47,8 @@
 #include "git-version.h"
 #include "version.h"
 
+#include "compositor-headless.h"
+
 static struct wl_list child_process_list;
 static struct weston_compositor *segv_compositor;
 
@@ -684,11 +686,45 @@ load_backend_new(struct weston_compositor *compositor, const char *backend,
 }
 
 static int
+load_headless_backend(struct weston_compositor *c, char const * backend,
+		      int *argc, char **argv, struct weston_config *wc)
+{
+	struct weston_headless_backend_config config = {{ 0, }};
+	int ret = 0;
+	const char *transform = "normal";
+
+	config.width = 1024;
+	config.height = 640;
+
+	const struct weston_option options[] = {
+		{ WESTON_OPTION_INTEGER, "width", 0, &config.width },
+		{ WESTON_OPTION_INTEGER, "height", 0, &config.height },
+		{ WESTON_OPTION_BOOLEAN, "use-pixman", 0, &config.use_pixman },
+		{ WESTON_OPTION_STRING, "transform", 0, &transform },
+	};
+
+	parse_options(options, ARRAY_LENGTH(options), argc, argv);
+
+	if (weston_parse_transform(transform, &config.transform) < 0)
+		weston_log("Invalid transform \"%s\"\n", transform);
+
+	config.base.struct_version = WESTON_HEADLESS_BACKEND_CONFIG_VERSION;
+	config.base.struct_size = sizeof(struct weston_headless_backend_config);
+
+	/* load the actual wayland backend and configure it */
+	ret = load_backend_new(c, backend, &config.base);
+
+	return ret;
+}
+
+static int
 load_backend(struct weston_compositor *compositor, const char *backend,
 	     int *argc, char **argv, struct weston_config *config)
 {
+	if (strstr(backend, "headless-backend.so"))
+		return load_headless_backend(compositor, backend, argc, argv, config);
 #if 0
-	if (strstr(backend, "drm-backend.so"))
+	else if (strstr(backend, "drm-backend.so"))
 		return load_drm_backend(compositor, backend, argc, argv, config);
 	else if (strstr(backend, "wayland-backend.so"))
 		return load_wayland_backend(compositor, backend, argc, argv, config);
@@ -696,8 +732,6 @@ load_backend(struct weston_compositor *compositor, const char *backend,
 		return load_x11_backend(compositor, backend, argc, argv, config);
 	else if (strstr(backend, "fbdev-backend.so"))
 		return load_fbdev_backend(compositor, backend, argc, argv, config);
-	else if (strstr(backend, "headless-backend.so"))
-		return load_headless_backend(compositor, backend, argc, argv, config);
 	else if (strstr(backend, "rpi-backend.so"))
 		return load_rpi_backend(compositor, backend, argc, argv, config);
 	else if (strstr(backend, "rdp-backend.so"))