Add a shm buffer sharing mechanism

TODO

@@ -17,13 +17,15 @@ Core wayland protocol
 
       buffer = drm.create_buffer(); /* buffer with stuff in it */
 
-      cache.upload(buffer, x, y, width, height, int key)
+      cache.upload(buffer, x, y, width, height, int hash)
 
       drm.buffer: id, name, stride etc /* event to announce cache buffer */
 
-      cache.image: key, buffer, x, y, stride /* event to announce
+      cache.image: hash, buffer, x, y, stride /* event to announce
 					      * location in cache */
 
+      cache.reject: hash   /* no upload for you! */
+
       cache.retire: buffer /* cache has stopped using buffer, please
 			    * reupload whatever you had in that buffer */
 

compositor/Makefile

@@ -1,6 +1,6 @@
 include ../config.mk
 
-CFLAGS += $(COMPOSITOR_CFLAGS)
+CFLAGS += -I../wayland $(COMPOSITOR_CFLAGS)
 LDLIBS += -L../wayland -lwayland-server $(COMPOSITOR_LIBS) -rdynamic -lrt -lm
 
 all : compositor
@@ -11,7 +11,8 @@ compositor :					\
 	compositor-x11.o			\
 	screenshooter.o				\
 	screenshooter-protocol.o		\
-	drm.o
+	drm.o					\
+	shm.o
 
 screenshooter.c : screenshooter-server-protocol.h
 

compositor/compositor.c

@@ -221,14 +221,6 @@ create_pointer_images(struct wlsc_compositor *ec)
 	GLuint texture;
 	const int width = 32, height = 32;
 
-	EGLint image_attribs[] = {
-		EGL_WIDTH,		0,
-		EGL_HEIGHT,		0,
-		EGL_DRM_BUFFER_FORMAT_MESA,	EGL_DRM_BUFFER_FORMAT_ARGB32_MESA,
-		EGL_DRM_BUFFER_USE_MESA,	EGL_DRM_BUFFER_USE_SCANOUT_MESA,
-		EGL_NONE
-	};
-
 	glGenTextures(1, &texture);
 	glBindTexture(GL_TEXTURE_2D, texture);
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
@@ -236,19 +228,15 @@ create_pointer_images(struct wlsc_compositor *ec)
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
 
-	image_attribs[1] = width;
-	image_attribs[3] = height;
 	count = ARRAY_LENGTH(pointer_images);
 	ec->pointer_buffers = malloc(count * sizeof *ec->pointer_buffers);
 	for (i = 0; i < count; i++) {
-		ec->pointer_buffers[i].image =
-			eglCreateDRMImageMESA(ec->display, image_attribs);
+		ec->pointer_buffers[i] =
+			wlsc_drm_buffer_create(ec, width, height,
+					       &ec->argb_visual);
 		glEGLImageTargetTexture2DOES(GL_TEXTURE_2D,
-					     ec->pointer_buffers[i].image);
+					     ec->pointer_buffers[i]->image);
 		texture_from_png(pointer_images[i].filename, width, height);
-		ec->pointer_buffers[i].visual = &ec->argb_visual;
-		ec->pointer_buffers[i].width = width;
-		ec->pointer_buffers[i].height = height;
 	}
 }
 
@@ -413,15 +401,12 @@ surface_destroy(struct wl_client *client,
 
 static void
 surface_attach(struct wl_client *client,
-	       struct wl_surface *surface, struct wl_buffer *buffer_base)
+	       struct wl_surface *surface, struct wl_buffer *buffer)
 {
 	struct wlsc_surface *es = (struct wlsc_surface *) surface;
-	struct wlsc_buffer *buffer = (struct wlsc_buffer *) buffer_base;
 
-	glBindTexture(GL_TEXTURE_2D, es->texture);
-	glEGLImageTargetTexture2DOES(GL_TEXTURE_2D, buffer->image);
-	es->visual = buffer->visual;
-	wlsc_compositor_schedule_repaint(es->compositor);
+	buffer->attach(buffer, surface);
+	es->buffer = buffer;
 }
 
 static void
@@ -447,6 +432,7 @@ surface_damage(struct wl_client *client,
 {
 	struct wlsc_surface *es = (struct wlsc_surface *) surface;
 
+	es->buffer->damage(es->buffer, surface, x, y, width, height);
 	wlsc_compositor_schedule_repaint(es->compositor);
 }
 
@@ -459,13 +445,11 @@ const static struct wl_surface_interface surface_interface = {
 
 static void
 wlsc_input_device_attach(struct wlsc_input_device *device,
-			 struct wlsc_buffer *buffer, int x, int y)
+			 struct wl_buffer *buffer, int x, int y)
 {
 	struct wlsc_compositor *ec = device->ec;
 
-	glBindTexture(GL_TEXTURE_2D, device->sprite->texture);
-	glEGLImageTargetTexture2DOES(GL_TEXTURE_2D, buffer->image);
-	device->sprite->visual = buffer->visual;
+	buffer->attach(buffer, &device->sprite->base);
 	device->hotspot_x = x;
 	device->hotspot_y = y;
 
@@ -486,7 +470,7 @@ wlsc_input_device_set_pointer_image(struct wlsc_input_device *device,
 	struct wlsc_compositor *compositor = device->ec;
 
 	wlsc_input_device_attach(device,
-				 &compositor->pointer_buffers[type],
+				 &compositor->pointer_buffers[type]->base,
 				 pointer_images[type].hotspot_x,
 				 pointer_images[type].hotspot_y);
 }
@@ -982,11 +966,10 @@ static void
 input_device_attach(struct wl_client *client,
 		    struct wl_input_device *device_base,
 		    uint32_t time,
-		    struct wl_buffer *buffer_base, int32_t x, int32_t y)
+		    struct wl_buffer *buffer, int32_t x, int32_t y)
 {
 	struct wlsc_input_device *device =
 		(struct wlsc_input_device *) device_base;
-	struct wlsc_buffer *buffer = (struct wlsc_buffer *) buffer_base;
 
 	if (time < device->pointer_focus_time)
 		return;
@@ -1391,6 +1374,8 @@ wlsc_compositor_init(struct wlsc_compositor *ec, struct wl_display *display)
 	if (wl_display_add_global(display, &ec->base.base, NULL))
 		return -1;
 
+	wlsc_shm_init(ec);
+
 	ec->shell.base.interface = &wl_shell_interface;
 	ec->shell.base.implementation = (void (**)(void)) &shell_interface;
 	wl_display_add_object(display, &ec->shell.base);

compositor/compositor.h

@@ -119,12 +119,19 @@ struct wlsc_drm {
 	char *filename;
 };
 
-struct wlsc_buffer {
+struct wlsc_drm_buffer {
 	struct wl_buffer base;
-	struct wlsc_compositor *compositor;
-	int32_t width, height;
 	EGLImageKHR image;
-	struct wl_visual *visual;
+};
+
+struct wlsc_shm {
+	struct wl_object base;
+};
+
+struct wlsc_shm_buffer {
+	struct wl_buffer base;
+	int32_t stride;
+	void *data;
 };
 
 struct wlsc_compositor {
@@ -132,11 +139,12 @@ struct wlsc_compositor {
 	struct wl_visual argb_visual, premultiplied_argb_visual, rgb_visual;
 
 	struct wlsc_drm drm;
+	struct wlsc_shm shm;
 	EGLDisplay display;
 	EGLContext context;
 	GLuint fbo, vbo;
 	GLuint proj_uniform, tex_uniform;
-	struct wlsc_buffer *pointer_buffers;
+	struct wlsc_drm_buffer **pointer_buffers;
 	struct wl_display *wl_display;
 
 	/* We implement the shell interface. */
@@ -180,6 +188,7 @@ struct wlsc_surface {
 	struct wlsc_matrix matrix;
 	struct wlsc_matrix matrix_inv;
 	struct wl_visual *visual;
+	struct wl_buffer *buffer;
 };
 
 void
@@ -197,6 +206,10 @@ wlsc_compositor_finish_frame(struct wlsc_compositor *compositor, int msecs);
 void
 wlsc_compositor_schedule_repaint(struct wlsc_compositor *compositor);
 
+struct wlsc_drm_buffer *
+wlsc_drm_buffer_create(struct wlsc_compositor *ec,
+		       int width, int height, struct wl_visual *visual);
+
 int
 wlsc_compositor_init(struct wlsc_compositor *ec, struct wl_display *display);
 void
@@ -208,6 +221,13 @@ wlsc_input_device_init(struct wlsc_input_device *device,
 int
 wlsc_drm_init(struct wlsc_compositor *ec, int fd, const char *filename);
 
+int
+wlsc_shm_init(struct wlsc_compositor *ec);
+
+struct wl_buffer *
+wl_buffer_create_drm(struct wlsc_compositor *compositor,
+		     struct wl_visual *visual);
+
 struct wlsc_compositor *
 x11_compositor_create(struct wl_display *display);
 

compositor/drm.c

@@ -41,9 +41,10 @@ drm_authenticate(struct wl_client *client,
 static void
 destroy_buffer(struct wl_resource *resource, struct wl_client *client)
 {
-	struct wlsc_buffer *buffer =
-		container_of(resource, struct wlsc_buffer, base.base);
-	struct wlsc_compositor *compositor = buffer->compositor;
+	struct wlsc_drm_buffer *buffer =
+		container_of(resource, struct wlsc_drm_buffer, base.base);
+	struct wlsc_compositor *compositor =
+		(struct wlsc_compositor *) buffer->base.compositor;
 
 	eglDestroyImageKHR(compositor->display, buffer->image);
 	free(buffer);
@@ -59,6 +60,25 @@ const static struct wl_buffer_interface buffer_interface = {
 	buffer_destroy
 };
 
+static void
+drm_buffer_attach(struct wl_buffer *buffer_base, struct wl_surface *surface)
+{
+	struct wlsc_surface *es = (struct wlsc_surface *) surface;
+	struct wlsc_drm_buffer *buffer =
+		(struct wlsc_drm_buffer *) buffer_base;
+
+	glBindTexture(GL_TEXTURE_2D, es->texture);
+	glEGLImageTargetTexture2DOES(GL_TEXTURE_2D, buffer->image);
+	es->visual = buffer->base.visual;
+}
+
+static void
+drm_buffer_damage(struct wl_buffer *buffer,
+		  struct wl_surface *surface,
+		  int32_t x, int32_t y, int32_t width, int32_t height)
+{
+}
+
 static void
 drm_create_buffer(struct wl_client *client, struct wl_drm *drm_base,
 		  uint32_t id, uint32_t name, int32_t width, int32_t height,
@@ -67,7 +87,7 @@ drm_create_buffer(struct wl_client *client, struct wl_drm *drm_base,
 	struct wlsc_drm *drm = (struct wlsc_drm *) drm_base;
 	struct wlsc_compositor *compositor =
 		container_of(drm, struct wlsc_compositor, drm);
-	struct wlsc_buffer *buffer;
+	struct wlsc_drm_buffer *buffer;
 	EGLint attribs[] = {
 		EGL_WIDTH,		0,
 		EGL_HEIGHT,		0,
@@ -98,10 +118,11 @@ drm_create_buffer(struct wl_client *client, struct wl_drm *drm_base,
 	attribs[3] = height;
 	attribs[5] = stride / 4;
 
-	buffer->compositor = compositor;
-	buffer->width = width;
-	buffer->height = height;
-	buffer->visual = visual;
+	buffer->base.compositor = &compositor->base;
+	buffer->base.width = width;
+	buffer->base.height = height;
+	buffer->base.visual = visual;
+	buffer->base.attach = drm_buffer_attach;
 	buffer->image = eglCreateImageKHR(compositor->display,
 					  compositor->context,
 					  EGL_DRM_BUFFER_MESA,
@@ -157,3 +178,40 @@ wlsc_drm_init(struct wlsc_compositor *ec, int fd, const char *filename)
 
 	return 0;
 }
+
+struct wlsc_drm_buffer *
+wlsc_drm_buffer_create(struct wlsc_compositor *ec,
+		       int width, int height, struct wl_visual *visual)
+{
+	struct wlsc_drm_buffer *buffer;
+
+	EGLint image_attribs[] = {
+		EGL_WIDTH,		0,
+		EGL_HEIGHT,		0,
+		EGL_DRM_BUFFER_FORMAT_MESA,	EGL_DRM_BUFFER_FORMAT_ARGB32_MESA,
+		EGL_DRM_BUFFER_USE_MESA,	EGL_DRM_BUFFER_USE_SCANOUT_MESA,
+		EGL_NONE
+	};
+
+	image_attribs[1] = width;
+	image_attribs[3] = height;
+
+	buffer = malloc(sizeof *buffer);
+	if (buffer == NULL)
+		return NULL;
+
+	buffer->image =
+		eglCreateDRMImageMESA(ec->display, image_attribs);
+	if (buffer->image == NULL) {
+		free(buffer);
+		return NULL;
+	}
+
+	buffer->base.visual = visual;
+	buffer->base.width = width;
+	buffer->base.height = height;
+	buffer->base.attach = drm_buffer_attach;
+	buffer->base.damage = drm_buffer_damage;
+
+	return buffer;
+}

compositor/shm.c

@@ -0,0 +1,156 @@
+/*
+ * Copyright © 2010 Kristian Høgsberg
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <unistd.h>
+
+#include "compositor.h"
+
+
+static void
+destroy_buffer(struct wl_resource *resource, struct wl_client *client)
+{
+	struct wlsc_shm_buffer *buffer =
+		container_of(resource, struct wlsc_shm_buffer, base.base);
+
+	munmap(buffer->data, buffer->stride * buffer->base.height);
+	free(buffer);
+}
+
+static void
+buffer_destroy(struct wl_client *client, struct wl_buffer *buffer)
+{
+	// wl_resource_destroy(&buffer->base, client);
+}
+
+const static struct wl_buffer_interface buffer_interface = {
+	buffer_destroy
+};
+
+static void
+shm_buffer_attach(struct wl_buffer *buffer_base, struct wl_surface *surface)
+{
+	struct wlsc_surface *es = (struct wlsc_surface *) surface;
+	struct wlsc_shm_buffer *buffer =
+		(struct wlsc_shm_buffer *) buffer_base;
+
+	glBindTexture(GL_TEXTURE_2D, es->texture);
+	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB,
+		     buffer->base.width, buffer->base.height, 0,
+		     GL_RGBA, GL_UNSIGNED_BYTE, buffer->data);
+	es->visual = buffer->base.visual;
+}
+
+static void
+shm_buffer_damage(struct wl_buffer *buffer_base,
+		  struct wl_surface *surface,
+		  int32_t x, int32_t y, int32_t width, int32_t height)
+{
+	struct wlsc_surface *es = (struct wlsc_surface *) surface;
+	struct wlsc_shm_buffer *buffer =
+		(struct wlsc_shm_buffer *) buffer_base;
+
+	glBindTexture(GL_TEXTURE_2D, es->texture);
+	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB,
+		     buffer->base.width, buffer->base.height, 0,
+		     GL_RGBA, GL_UNSIGNED_BYTE, buffer->data);
+
+	/* Hmm, should use glTexSubImage2D() here but GLES2 doesn't
+	 * support any unpack attributes except GL_UNPACK_ALIGNMENT. */
+}
+
+static void
+shm_create_buffer(struct wl_client *client, struct wl_shm *shm,
+		  uint32_t id, int fd, int32_t width, int32_t height,
+		  uint32_t stride, struct wl_visual *visual)
+{
+	struct wlsc_compositor *compositor =
+		container_of((struct wlsc_shm *) shm,
+			     struct wlsc_compositor, shm);
+	struct wlsc_shm_buffer *buffer;
+
+	if (visual != &compositor->argb_visual &&
+	    visual != &compositor->premultiplied_argb_visual &&
+	    visual != &compositor->rgb_visual) {
+		/* FIXME: Define a real exception event instead of
+		 * abusing this one */
+		wl_client_post_event(client,
+				     (struct wl_object *) compositor->wl_display,
+				     WL_DISPLAY_INVALID_OBJECT, 0);
+		fprintf(stderr, "invalid visual in create_buffer\n");
+		close(fd);
+		return;
+	}
+
+	buffer = malloc(sizeof *buffer);
+	if (buffer == NULL) {
+		close(fd);
+		wl_client_post_no_memory(client);
+		return;
+	}
+
+	buffer->base.compositor = (struct wl_compositor *) compositor;
+	buffer->base.width = width;
+	buffer->base.height = height;
+	buffer->base.visual = visual;
+	buffer->base.attach = shm_buffer_attach;
+	buffer->base.damage = shm_buffer_damage;
+	buffer->stride = stride;
+	buffer->data =
+		mmap(NULL, stride * height, PROT_READ, MAP_SHARED, fd, 0);
+	close(fd);
+	if (buffer->data == MAP_FAILED) {
+		/* FIXME: Define a real exception event instead of
+		 * abusing this one */
+		free(buffer);
+		wl_client_post_event(client,
+				     (struct wl_object *) compositor->wl_display,
+				     WL_DISPLAY_INVALID_OBJECT, 0);
+		fprintf(stderr, "failed to create image for fd %d\n", fd);
+		return;
+	}
+
+	buffer->base.base.base.id = id;
+	buffer->base.base.base.interface = &wl_buffer_interface;
+	buffer->base.base.base.implementation = (void (**)(void))
+		&buffer_interface;
+
+	buffer->base.base.destroy = destroy_buffer;
+
+	wl_client_add_resource(client, &buffer->base.base);
+}
+
+const static struct wl_shm_interface shm_interface = {
+	shm_create_buffer
+};
+
+int
+wlsc_shm_init(struct wlsc_compositor *ec)
+{
+	struct wlsc_shm *shm = &ec->shm;
+
+	shm->base.interface = &wl_shm_interface;
+	shm->base.implementation = (void (**)(void)) &shm_interface;
+	wl_display_add_object(ec->wl_display, &shm->base);
+	wl_display_add_global(ec->wl_display, &shm->base, NULL);
+
+	return 0;
+}

wayland/protocol.xml

@@ -68,6 +68,17 @@
     <event name="authenticated"/>
   </interface>
 
+  <interface name="shm" version="1">
+    <request name="create_buffer">
+      <arg name="id" type="new_id" interface="buffer"/>
+      <arg name="fd" type="fd"/>
+      <arg name="width" type="int"/>
+      <arg name="height" type="int"/>
+      <arg name="stride" type="uint"/>
+      <arg name="visual" type="object" interface="visual"/>
+    </request>
+  </interface>
+
   <interface name="buffer" version="1">
     <request name="destroy" type="destructor"/>
   </interface>

wayland/wayland-server.h

@@ -107,6 +107,13 @@ struct wl_resource {
 
 struct wl_buffer {
 	struct wl_resource base;
+	struct wl_compositor *compositor;
+	struct wl_visual *visual;
+	int32_t width, height;
+	void (*attach)(struct wl_buffer *buffer, struct wl_surface *surface);
+	void (*damage)(struct wl_buffer *buffer,
+		       struct wl_surface *surface,
+		       int32_t x, int32_t y, int32_t width, int32_t height);
 };
 
 struct wl_surface {