backend/wayland: add support for wl_shm buffers

backend/wayland/backend.c

@@ -20,6 +20,7 @@
 #include "backend/wayland.h"
 #include "render/drm_format_set.h"
 #include "render/gbm_allocator.h"
+#include "render/pixel_format.h"
 #include "render/wlr_renderer.h"
 #include "util/signal.h"
 
@@ -190,6 +191,17 @@ static const struct wl_drm_listener legacy_drm_listener = {
 	.capabilities = legacy_drm_handle_capabilities,
 };
 
+static void shm_handle_format(void *data, struct wl_shm *shm,
+		uint32_t shm_format) {
+	struct wlr_wl_backend *wl = data;
+	uint32_t drm_format = convert_wl_shm_format_to_drm(shm_format);
+	wlr_drm_format_set_add(&wl->shm_formats, drm_format, DRM_FORMAT_MOD_INVALID);
+}
+
+static const struct wl_shm_listener shm_listener = {
+	.format = shm_handle_format,
+};
+
 static void registry_global(void *data, struct wl_registry *registry,
 		uint32_t name, const char *iface, uint32_t version) {
 	struct wlr_wl_backend *wl = data;
@@ -233,6 +245,9 @@ static void registry_global(void *data, struct wl_registry *registry,
 	} else if (strcmp(iface, wl_drm_interface.name) == 0) {
 		wl->legacy_drm = wl_registry_bind(registry, name, &wl_drm_interface, 1);
 		wl_drm_add_listener(wl->legacy_drm, &legacy_drm_listener, wl);
+	} else if (strcmp(iface, wl_shm_interface.name) == 0) {
+		wl->shm = wl_registry_bind(registry, name, &wl_shm_interface, 1);
+		wl_shm_add_listener(wl->shm, &shm_listener, wl);
 	}
 }
 
@@ -302,6 +317,7 @@ static void backend_destroy(struct wlr_backend *backend) {
 	wlr_allocator_destroy(wl->allocator);
 	close(wl->drm_fd);
 
+	wlr_drm_format_set_finish(&wl->shm_formats);
 	wlr_drm_format_set_finish(&wl->linux_dmabuf_v1_formats);
 
 	struct wlr_wl_buffer *buffer, *tmp_buffer;
@@ -322,6 +338,9 @@ static void backend_destroy(struct wlr_backend *backend) {
 	if (wl->zwp_linux_dmabuf_v1) {
 		zwp_linux_dmabuf_v1_destroy(wl->zwp_linux_dmabuf_v1);
 	}
+	if (wl->shm) {
+		wl_shm_destroy(wl->shm);
+	}
 	if (wl->zwp_relative_pointer_manager_v1) {
 		zwp_relative_pointer_manager_v1_destroy(wl->zwp_relative_pointer_manager_v1);
 	}

backend/wayland/output.c

@@ -7,6 +7,7 @@
 #include <sys/types.h>
 #include <unistd.h>
 
+#include <drm_fourcc.h>
 #include <wayland-client.h>
 
 #include <wlr/interfaces/wlr_output.h>
@@ -15,6 +16,7 @@
 #include <wlr/util/log.h>
 
 #include "backend/wayland.h"
+#include "render/pixel_format.h"
 #include "render/swapchain.h"
 #include "render/wlr_renderer.h"
 #include "util/signal.h"
@@ -161,52 +163,79 @@ static void buffer_handle_buffer_destroy(struct wl_listener *listener,
 
 static bool test_buffer(struct wlr_wl_backend *wl,
 		struct wlr_buffer *wlr_buffer) {
-	struct wlr_dmabuf_attributes attribs;
-	if (!wlr_buffer_get_dmabuf(wlr_buffer, &attribs)) {
-		return false;
-	}
-
-	if (!wlr_drm_format_set_has(&wl->linux_dmabuf_v1_formats,
-			attribs.format, attribs.modifier)) {
+	struct wlr_dmabuf_attributes dmabuf;
+	struct wlr_shm_attributes shm;
+	if (wlr_buffer_get_dmabuf(wlr_buffer, &dmabuf)) {
+		return wlr_drm_format_set_has(&wl->linux_dmabuf_v1_formats,
+			dmabuf.format, dmabuf.modifier);
+	} else if (wlr_buffer_get_shm(wlr_buffer, &shm)) {
+		return wlr_drm_format_set_has(&wl->shm_formats, shm.format,
+			DRM_FORMAT_MOD_INVALID);
+	} else {
 		return false;
 	}
-
-	return true;
-}
-
-static struct wlr_wl_buffer *create_wl_buffer(struct wlr_wl_backend *wl,
-		struct wlr_buffer *wlr_buffer) {
-	if (!test_buffer(wl, wlr_buffer)) {
-		return NULL;
-	}
-
-	struct wlr_dmabuf_attributes attribs;
-	if (!wlr_buffer_get_dmabuf(wlr_buffer, &attribs)) {
-		return NULL;
 }
 
-	uint32_t modifier_hi = attribs.modifier >> 32;
-	uint32_t modifier_lo = (uint32_t)attribs.modifier;
+static struct wl_buffer *import_dmabuf(struct wlr_wl_backend *wl,
+		struct wlr_dmabuf_attributes *dmabuf) {
+	uint32_t modifier_hi = dmabuf->modifier >> 32;
+	uint32_t modifier_lo = (uint32_t)dmabuf->modifier;
 	struct zwp_linux_buffer_params_v1 *params =
 		zwp_linux_dmabuf_v1_create_params(wl->zwp_linux_dmabuf_v1);
-	for (int i = 0; i < attribs.n_planes; i++) {
-		zwp_linux_buffer_params_v1_add(params, attribs.fd[i], i,
-			attribs.offset[i], attribs.stride[i], modifier_hi, modifier_lo);
+	for (int i = 0; i < dmabuf->n_planes; i++) {
+		zwp_linux_buffer_params_v1_add(params, dmabuf->fd[i], i,
+			dmabuf->offset[i], dmabuf->stride[i], modifier_hi, modifier_lo);
 	}
 
 	uint32_t flags = 0;
-	if (attribs.flags & WLR_DMABUF_ATTRIBUTES_FLAGS_Y_INVERT) {
+	if (dmabuf->flags & WLR_DMABUF_ATTRIBUTES_FLAGS_Y_INVERT) {
 		flags |= ZWP_LINUX_BUFFER_PARAMS_V1_FLAGS_Y_INVERT;
 	}
-	if (attribs.flags & WLR_DMABUF_ATTRIBUTES_FLAGS_INTERLACED) {
+	if (dmabuf->flags & WLR_DMABUF_ATTRIBUTES_FLAGS_INTERLACED) {
 		flags |= ZWP_LINUX_BUFFER_PARAMS_V1_FLAGS_INTERLACED;
 	}
-	if (attribs.flags & WLR_DMABUF_ATTRIBUTES_FLAGS_BOTTOM_FIRST) {
+	if (dmabuf->flags & WLR_DMABUF_ATTRIBUTES_FLAGS_BOTTOM_FIRST) {
 		flags |= ZWP_LINUX_BUFFER_PARAMS_V1_FLAGS_BOTTOM_FIRST;
 	}
 	struct wl_buffer *wl_buffer = zwp_linux_buffer_params_v1_create_immed(
-		params, attribs.width, attribs.height, attribs.format, flags);
+		params, dmabuf->width, dmabuf->height, dmabuf->format, flags);
 	// TODO: handle create() errors
+	return wl_buffer;
+}
+
+static struct wl_buffer *import_shm(struct wlr_wl_backend *wl,
+		struct wlr_shm_attributes *shm) {
+	enum wl_shm_format wl_shm_format = convert_drm_format_to_wl_shm(shm->format);
+	uint32_t size = shm->stride * shm->height;
+	struct wl_shm_pool *pool = wl_shm_create_pool(wl->shm, shm->fd, size);
+	if (pool == NULL) {
+		return NULL;
+	}
+	struct wl_buffer *wl_buffer = wl_shm_pool_create_buffer(pool, shm->offset,
+		shm->width, shm->height, shm->stride, wl_shm_format);
+	wl_shm_pool_destroy(pool);
+	return wl_buffer;
+}
+
+static struct wlr_wl_buffer *create_wl_buffer(struct wlr_wl_backend *wl,
+		struct wlr_buffer *wlr_buffer) {
+	if (!test_buffer(wl, wlr_buffer)) {
+		return NULL;
+	}
+
+	struct wlr_dmabuf_attributes dmabuf;
+	struct wlr_shm_attributes shm;
+	struct wl_buffer *wl_buffer;
+	if (wlr_buffer_get_dmabuf(wlr_buffer, &dmabuf)) {
+		wl_buffer = import_dmabuf(wl, &dmabuf);
+	} else if (wlr_buffer_get_shm(wlr_buffer, &shm)) {
+		wl_buffer = import_shm(wl, &shm);
+	} else {
+		return NULL;
+	}
+	if (wl_buffer == NULL) {
+		return NULL;
+	}
 
 	struct wlr_wl_buffer *buffer = calloc(1, sizeof(struct wlr_wl_buffer));
 	if (buffer == NULL) {

include/backend/wayland.h

@@ -38,10 +38,12 @@ struct wlr_wl_backend {
 	struct zxdg_decoration_manager_v1 *zxdg_decoration_manager_v1;
 	struct zwp_pointer_gestures_v1 *zwp_pointer_gestures_v1;
 	struct wp_presentation *presentation;
+	struct wl_shm *shm;
 	struct zwp_linux_dmabuf_v1 *zwp_linux_dmabuf_v1;
 	struct zwp_relative_pointer_manager_v1 *zwp_relative_pointer_manager_v1;
 	struct wl_list seats; // wlr_wl_seat.link
 	struct zwp_tablet_manager_v2 *tablet_manager;
+	struct wlr_drm_format_set shm_formats;
 	struct wlr_drm_format_set linux_dmabuf_v1_formats;
 	struct wl_drm *legacy_drm;
 	char *drm_render_name;