backends: refactor transform string parsing

Most of the backends do their own parsing of transform strings, so let's
put that all in the same place (compositor.c/h)

Reviewed-by: Pekka Paalanen <pekka.paalanen@collabora.co.uk>

src/compositor-drm.c

@@ -1862,31 +1862,6 @@ parse_modeline(const char *s, drmModeModeInfo *mode)
 	return 0;
 }
 
-static uint32_t
-parse_transform(const char *transform, const char *output_name)
-{
-	static const struct { const char *name; uint32_t token; } names[] = {
-		{ "normal",	WL_OUTPUT_TRANSFORM_NORMAL },
-		{ "90",		WL_OUTPUT_TRANSFORM_90 },
-		{ "180",	WL_OUTPUT_TRANSFORM_180 },
-		{ "270",	WL_OUTPUT_TRANSFORM_270 },
-		{ "flipped",	WL_OUTPUT_TRANSFORM_FLIPPED },
-		{ "flipped-90",	WL_OUTPUT_TRANSFORM_FLIPPED_90 },
-		{ "flipped-180", WL_OUTPUT_TRANSFORM_FLIPPED_180 },
-		{ "flipped-270", WL_OUTPUT_TRANSFORM_FLIPPED_270 },
-	};
-	unsigned int i;
-
-	for (i = 0; i < ARRAY_LENGTH(names); i++)
-		if (strcmp(names[i].name, transform) == 0)
-			return names[i].token;
-
-	weston_log("Invalid transform \"%s\" for output %s\n",
-		   transform, output_name);
-
-	return WL_OUTPUT_TRANSFORM_NORMAL;
-}
-
 static void
 setup_output_seat_constraint(struct drm_compositor *ec,
 			     struct weston_output *output,
@@ -1999,7 +1974,10 @@ create_output_for_connector(struct drm_compositor *ec,
 
 	weston_config_section_get_int(section, "scale", &scale, 1);
 	weston_config_section_get_string(section, "transform", &s, "normal");
-	transform = parse_transform(s, output->base.name);
+	if (weston_parse_transform(s, &transform) < 0)
+		weston_log("Invalid transform \"%s\" for output %s\n",
+			   s, output->base.name);
+
 	free(s);
 
 	if (get_gbm_format_from_section(section,

src/compositor-rpi.c

@@ -281,38 +281,6 @@ rpi_output_destroy(struct weston_output *base)
 	free(output);
 }
 
-static const char *transform_names[] = {
-	[WL_OUTPUT_TRANSFORM_NORMAL] = "normal",
-	[WL_OUTPUT_TRANSFORM_90] = "90",
-	[WL_OUTPUT_TRANSFORM_180] = "180",
-	[WL_OUTPUT_TRANSFORM_270] = "270",
-	[WL_OUTPUT_TRANSFORM_FLIPPED] = "flipped",
-	[WL_OUTPUT_TRANSFORM_FLIPPED_90] = "flipped-90",
-	[WL_OUTPUT_TRANSFORM_FLIPPED_180] = "flipped-180",
-	[WL_OUTPUT_TRANSFORM_FLIPPED_270] = "flipped-270",
-};
-
-static int
-str2transform(const char *name)
-{
-	unsigned i;
-
-	for (i = 0; i < ARRAY_LENGTH(transform_names); i++)
-		if (strcmp(name, transform_names[i]) == 0)
-			return i;
-
-	return -1;
-}
-
-static const char *
-transform2str(uint32_t output_transform)
-{
-	if (output_transform >= ARRAY_LENGTH(transform_names))
-		return "<illegal value>";
-
-	return transform_names[output_transform];
-}
-
 static int
 rpi_output_create(struct rpi_compositor *compositor, uint32_t transform)
 {
@@ -390,9 +358,10 @@ rpi_output_create(struct rpi_compositor *compositor, uint32_t transform)
 	weston_log_continue(STAMP_SPACE "guessing %d Hz and 96 dpi\n",
 			    output->mode.refresh / 1000);
 	weston_log_continue(STAMP_SPACE "orientation: %s\n",
-			    transform2str(output->base.transform));
+			    weston_transform_to_string(output->base.transform));
 
-	if (!strncmp(transform2str(output->base.transform), "flipped", 7))
+	if (!strncmp(weston_transform_to_string(output->base.transform),
+						"flipped", 7))
 		weston_log("warning: flipped output transforms may not work\n");
 
 	return 0;
@@ -580,7 +549,6 @@ backend_init(struct wl_display *display, int *argc, char *argv[],
 	     struct weston_config *config)
 {
 	const char *transform = "normal";
-	int ret;
 
 	struct rpi_parameters param = {
 		.tty = 0, /* default to current tty */
@@ -600,11 +568,8 @@ backend_init(struct wl_display *display, int *argc, char *argv[],
 
 	parse_options(rpi_options, ARRAY_LENGTH(rpi_options), argc, argv);
 
-	ret = str2transform(transform);
+	if (weston_parse_transform(transform, &param.output_transform) < 0)
-	if (ret < 0)
 		weston_log("invalid transform \"%s\"\n", transform);
-	else
-		param.output_transform = ret;
 
 	return rpi_compositor_create(display, argc, argv, config, &param);
 }

src/compositor-wayland.c

@@ -1077,18 +1077,7 @@ wayland_output_create_for_config(struct wayland_compositor *c,
 	char *mode, *t, *name, *str;
 	int width, height, scale;
 	uint32_t transform;
-	unsigned int i, slen;
+	unsigned int slen;
-
-	static const struct { const char *name; uint32_t token; } transform_names[] = {
-		{ "normal",	WL_OUTPUT_TRANSFORM_NORMAL },
-		{ "90",		WL_OUTPUT_TRANSFORM_90 },
-		{ "180",	WL_OUTPUT_TRANSFORM_180 },
-		{ "270",	WL_OUTPUT_TRANSFORM_270 },
-		{ "flipped",	WL_OUTPUT_TRANSFORM_FLIPPED },
-		{ "flipped-90",	WL_OUTPUT_TRANSFORM_FLIPPED_90 },
-		{ "flipped-180", WL_OUTPUT_TRANSFORM_FLIPPED_180 },
-		{ "flipped-270", WL_OUTPUT_TRANSFORM_FLIPPED_270 },
-	};
 
 	weston_config_section_get_string(config_section, "name", &name, NULL);
 	if (name) {
@@ -1125,15 +1114,9 @@ wayland_output_create_for_config(struct wayland_compositor *c,
 
 	weston_config_section_get_string(config_section,
 					 "transform", &t, "normal");
-	transform = WL_OUTPUT_TRANSFORM_NORMAL;
+	if (weston_parse_transform(t, &transform) < 0)
-	for (i = 0; i < ARRAY_LENGTH(transform_names); i++) {
+		weston_log("Invalid transform \"%s\" for output %s\n",
-		if (strcmp(transform_names[i].name, t) == 0) {
+			   t, name);
-			transform = transform_names[i].token;
-			break;
-		}
-	}
-	if (i >= ARRAY_LENGTH(transform_names))
-		weston_log("Invalid transform \"%s\" for output %s\n", t, name);
 	free(t);
 
 	output = wayland_output_create(c, x, y, width, height, name, 0,

src/compositor-x11.c

@@ -1429,31 +1429,6 @@ x11_destroy(struct weston_compositor *ec)
 	free(ec);
 }
 
-static uint32_t
-parse_transform(const char *transform, const char *output_name)
-{
-	static const struct { const char *name; uint32_t token; } names[] = {
-		{ "normal",	WL_OUTPUT_TRANSFORM_NORMAL },
-		{ "90",		WL_OUTPUT_TRANSFORM_90 },
-		{ "180",	WL_OUTPUT_TRANSFORM_180 },
-		{ "270",	WL_OUTPUT_TRANSFORM_270 },
-		{ "flipped",	WL_OUTPUT_TRANSFORM_FLIPPED },
-		{ "flipped-90",	WL_OUTPUT_TRANSFORM_FLIPPED_90 },
-		{ "flipped-180", WL_OUTPUT_TRANSFORM_FLIPPED_180 },
-		{ "flipped-270", WL_OUTPUT_TRANSFORM_FLIPPED_270 },
-	};
-	unsigned int i;
-
-	for (i = 0; i < ARRAY_LENGTH(names); i++)
-		if (strcmp(names[i].name, transform) == 0)
-			return names[i].token;
-
-	weston_log("Invalid transform \"%s\" for output %s\n",
-		   transform, output_name);
-
-	return WL_OUTPUT_TRANSFORM_NORMAL;
-}
-
 static int
 init_gl_renderer(struct x11_compositor *c)
 {
@@ -1576,7 +1551,9 @@ x11_compositor_create(struct wl_display *display,
 
 		weston_config_section_get_string(section,
 						 "transform", &t, "normal");
-		transform = parse_transform(t, name);
+		if (weston_parse_transform(t, &transform) < 0)
+			weston_log("Invalid transform \"%s\" for output %s\n",
+				   t, name);
 		free(t);
 
 		output = x11_compositor_create_output(c, x, 0,

src/compositor.c

@@ -4656,6 +4656,45 @@ weston_create_listening_socket(struct wl_display *display, const char *socket_na
 	return 0;
 }
 
+static const struct { const char *name; uint32_t token; } transforms[] = {
+	{ "normal",     WL_OUTPUT_TRANSFORM_NORMAL },
+	{ "90",         WL_OUTPUT_TRANSFORM_90 },
+	{ "180",        WL_OUTPUT_TRANSFORM_180 },
+	{ "270",        WL_OUTPUT_TRANSFORM_270 },
+	{ "flipped",    WL_OUTPUT_TRANSFORM_FLIPPED },
+	{ "flipped-90", WL_OUTPUT_TRANSFORM_FLIPPED_90 },
+	{ "flipped-180", WL_OUTPUT_TRANSFORM_FLIPPED_180 },
+	{ "flipped-270", WL_OUTPUT_TRANSFORM_FLIPPED_270 },
+};
+
+WL_EXPORT int
+weston_parse_transform(const char *transform, uint32_t *out)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_LENGTH(transforms); i++)
+		if (strcmp(transforms[i].name, transform) == 0) {
+			*out = transforms[i].token;
+			return 0;
+		}
+
+	*out = WL_OUTPUT_TRANSFORM_NORMAL;
+	return -1;
+}
+
+WL_EXPORT const char *
+weston_transform_to_string(uint32_t output_transform)
+{
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_LENGTH(transforms); i++)
+		if (transforms[i].token == output_transform)
+			return transforms[i].name;
+
+	return "<illegal value>";
+}
+
+
 int main(int argc, char *argv[])
 {
 	int ret = EXIT_SUCCESS;

src/compositor.h

@@ -1473,6 +1473,12 @@ weston_transformed_region(int width, int height,
 void *
 weston_load_module(const char *name, const char *entrypoint);
 
+int
+weston_parse_transform(const char *transform, uint32_t *out);
+
+const char *
+weston_transform_to_string(uint32_t output_transform);
+
 #ifdef  __cplusplus
 }
 #endif