--- /dev/null
+
+KEYWORDS:
+
+Wayland is a nano display server, relying on drm modesetting, gem
+batchbuffer submission and hw initialization generally in the
+kernel. Wayland is compositing manager and display server in one
+process. window management is largely pushed to the clients, they
+draw their own decorations and move and resize themselves,
+typically implemented in a library. more of the core desktop could
+be pushed into wayland, for example, stock desktop components such
+as the panel or the desktop background.
+
+It is still designed with a windowed type of desktop in mind, as
+opposed to fullscreen-all-the-time type of interface.
+
+Current trends goes towards less and less rendering in X server,
+more hardware setup and management in kernel and shared libraries
+allow code sharing without putting it all in a server.
+
+Client allocates DRM buffers, draws decorations, and full window
+contents and posts entire thing to server along with dimensions.
+
+Everything is direct rendered and composited. No cliprects, no
+drawing api/protocl between server and client. No
+pixmaps/windows/drawables, only surfaces (essentially pixmaps). No
+gcs/fonts, no nested windows. OpenGL is already direct rendered,
+pixman may be direct rendered which adds the cairo API, or cairo
+may gain a GL backend.
+
+ISSUES:
+
+Include panel and desktop background in wayland?
+
+How does clients move their surfaces? set a full tri-mesh every time?
+
+How does the server apply transformations to a surface behind the
+clients back? (wobbly, minimize, zoom) Maybe wobble is client side?
+
+How do apps share the glyph cache?
+
+Input handling - keyboard focus, multiple input devices, multiple
+pointers, multi touch.
+
+Drawing cursors, moving them, cursor themes, attaching surfaces to
+cursors. How do you change cursors when you mouse over a text
+field if you don't have subwindows?
+
+synaptics, 3-button emulation, xkb, scim
+
+RMI
+
+the get_interface method is called on an object to get an object
+handle that implements the specified interface.
\ No newline at end of file
--- /dev/null
+#include <stdlib.h>
+#include <stdint.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <ctype.h>
+
+static const char socket_name[] = "\0wayland";
+
+struct method {
+ const char *name;
+ uint32_t opcode;
+};
+
+static const struct method display_methods[] = {
+ { "get_interface", 0 },
+ { "create_surface", 1 },
+ { NULL }
+};
+
+static const struct method surface_methods[] = {
+ { "get_interface", 0 },
+ { "post", 1 },
+ { NULL }
+};
+
+struct interface {
+ const char *name;
+ const struct method *methods;
+};
+
+static const struct interface interfaces[] = {
+ { "display", display_methods },
+ { "surface", surface_methods },
+ { NULL },
+};
+
+int send_request(int sock, const char *buffer, int buffer_len)
+{
+ const struct method *methods;
+ char interface[32], method[32];
+ uint32_t request[3], id, new_id;
+ int i;
+
+ if (sscanf(buffer, "%d/%32[^:]:%32s %d\n",
+ &id, interface, method, &new_id) != 4) {
+ printf("invalid input, expected <id>/<interface>:<method>\n");
+ return -1;
+ }
+
+ printf("got object id %d, interface \"%s\", name \"%s\"\n",
+ id, interface, method);
+
+ for (i = 0; interfaces[i].name != NULL; i++) {
+ if (strcmp(interfaces[i].name, interface) == 0)
+ break;
+ }
+ if (interfaces[i].name == NULL) {
+ printf("unknown interface \"%s\"\n", interface);
+ return -1;
+ }
+
+ methods = interfaces[i].methods;
+ for (i = 0; methods[i].name != NULL; i++) {
+ if (strcmp(methods[i].name, method) == 0)
+ break;
+ }
+
+ if (methods[i].name == NULL) {
+ printf("unknown request \"%s\"\n", method);
+ return -1;
+ }
+
+ request[0] = id;
+ request[1] = methods[i].opcode;
+ request[2] = new_id;
+
+ return write(sock, request, sizeof request);
+}
+
+int main(int argc, char *argv[])
+{
+ struct sockaddr_un name;
+ socklen_t size;
+ int sock, len;
+ char buffer[256];
+
+ sock = socket(PF_LOCAL, SOCK_STREAM, 0);
+ if (sock < 0)
+ return -1;
+
+ name.sun_family = AF_LOCAL;
+ memcpy(name.sun_path, socket_name, sizeof socket_name);
+
+ size = offsetof (struct sockaddr_un, sun_path) + sizeof socket_name;
+
+ if (connect (sock, (struct sockaddr *) &name, size) < 0)
+ return -1;
+
+ while (len = read(STDIN_FILENO, buffer, sizeof buffer), len > 0)
+ if (send_request(sock, buffer, len) < 0)
+ break;
+
+ return 0;
+}
--- /dev/null
+#include <stdlib.h>
+#include <stdint.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <ffi.h>
+#include "wayland.h"
+
+#define ARRAY_LENGTH(a) (sizeof (a) / sizeof (a)[0])
+
+struct wl_region {
+};
+
+struct wl_client {
+ char protocol_buffer[4096];
+ struct wl_event_source *source;
+ struct wl_display *display;
+};
+
+struct wl_display {
+ struct wl_object base;
+ struct wl_event_loop *loop;
+ struct wl_hash objects;
+};
+
+struct wl_surface {
+ struct wl_object base;
+
+ /* provided by client */
+ int width, height;
+ int buffer;
+ int stride;
+
+ /* these are used by the wayland server, not set from client */
+ void (*screen_to_surface)(int sx, int sy, int *wx, int *wy);
+ void (*surface_to_screen)(int sx, int sy, int *wx, int *wy);
+
+ /* how to convert buffer contents to pixels in screen format;
+ * yuv->rgb, indexed->rgb, svg->rgb, but mostly just rgb->rgb. */
+
+ /* how to transform/render rectangular contents to polygons. */
+};
+
+static void
+wl_surface_get_interface(struct wl_client *client,
+ struct wl_surface *surface,
+ const char *interface, uint32_t id)
+{
+ /* client sends a new object id, and an interface identifier
+ * to name the object that implements the interface */
+ printf("surface::get_interface\n");
+}
+
+static const struct wl_argument get_interface_arguments[] = {
+ { WL_ARGUMENT_STRING },
+ { WL_ARGUMENT_NEW_ID }
+};
+
+static void
+wl_surface_post(struct wl_client *client,
+ struct wl_surface *surface, uint32_t name,
+ uint32_t width, uint32_t height, uint32_t stride)
+{
+ printf("surface::post\n");
+}
+
+static const struct wl_argument post_arguments[] = {
+ { WL_ARGUMENT_UINT32 },
+ { WL_ARGUMENT_UINT32 },
+ { WL_ARGUMENT_UINT32 },
+ { WL_ARGUMENT_UINT32 },
+};
+
+void
+wl_surface_update(struct wl_surface *surface,
+ uint32_t source_name, struct wl_region *region)
+{
+ /* FIXME: how to demarshal region? */
+ /* copy region from buffer into current window contents. */
+}
+
+static const struct wl_argument update_arguments[] = {
+ { WL_ARGUMENT_UINT32 },
+ { WL_ARGUMENT_UINT32 },
+};
+
+static const struct wl_method surface_methods[] = {
+ { "get_interface", wl_surface_get_interface,
+ ARRAY_LENGTH(get_interface_arguments), get_interface_arguments },
+ { "post", wl_surface_post,
+ ARRAY_LENGTH(post_arguments), post_arguments }
+};
+
+static const struct wl_interface surface_interface = {
+ "surface", 1,
+ ARRAY_LENGTH(surface_methods),
+ surface_methods,
+};
+
+struct wl_surface *
+wl_surface_create(struct wl_display *display, uint32_t id)
+{
+ struct wl_surface *surface;
+
+ surface = malloc(sizeof *surface);
+ if (surface == NULL)
+ return NULL;
+
+ surface->base.id = id;
+ surface->base.interface = &surface_interface;
+ /* doesn't create any pixel buffers, just the wl_surface
+ * object. the client allocates and attaches pixel buffers
+ * itself and renders to them, then posts them using
+ * wl_window_post. */
+
+ /* add to display list */
+
+ return surface;
+}
+
+static void
+wl_client_data(int fd, uint32_t mask, void *data);
+
+struct wl_client *
+wl_client_create(struct wl_display *display, int fd)
+{
+ struct wl_client *client;
+
+ client = malloc(sizeof *client);
+ if (client == NULL)
+ return NULL;
+
+ client->display = display;
+
+ client->source = wl_event_loop_add_fd(display->loop, fd,
+ WL_EVENT_READABLE |
+ WL_EVENT_READABLE,
+ wl_client_data, client);
+
+ printf("new client: %p\n", client);
+
+ /* Send global objects to client in hand shake response, eg:
+ *
+ * display: 0,
+ * glyph_cache: 1
+ * some other extension global object: 2
+ *
+ * etc */
+
+ return client;
+}
+
+void
+wl_client_destroy(struct wl_client *client)
+{
+ printf("disconnect from client %p\n", client);
+ wl_event_loop_remove_source(client->display->loop, client->source);
+ free(client);
+}
+
+static void
+demarshal(struct wl_client *client, struct wl_object *target,
+ const struct wl_method *method, uint32_t *data, int len)
+{
+ ffi_type *types[10];
+ ffi_cif cif;
+ uint32_t *p, result;
+ int i;
+ union {
+ uint32_t uint32;
+ const char *string;
+ void *object;
+ uint32_t new_id;
+ } values[10];
+ void *args[10];
+ struct wl_object *object;
+
+ if (method->argument_count > ARRAY_LENGTH(types)) {
+ printf("too many args (%d)\n", method->argument_count);
+ return;
+ }
+
+ types[0] = &ffi_type_pointer;
+ values[0].object = client;
+ args[0] = &values[0];
+
+ types[1] = &ffi_type_pointer;
+ values[1].object = target;
+ args[1] = &values[1];
+
+ p = data;
+ for (i = 0; i < method->argument_count; i++) {
+ switch (method->arguments[i].type) {
+ case WL_ARGUMENT_UINT32:
+ types[i + 2] = &ffi_type_uint32;
+ values[i + 2].uint32 = *p;
+ printf("got uint32 (%d)\n", *p);
+ p++;
+ break;
+ case WL_ARGUMENT_STRING:
+ printf("got string\n");
+ types[i + 2] = &ffi_type_pointer;
+ /* FIXME */
+ values[i + 2].uint32 = *p++;
+ break;
+ case WL_ARGUMENT_OBJECT:
+ types[i + 2] = &ffi_type_pointer;
+ object = wl_hash_lookup(&client->display->objects, *p);
+ if (object == NULL)
+ printf("unknown object (%d)\n", *p);
+ if (object->interface != method->arguments[i].data)
+ printf("wrong object type\n");
+ values[i + 2].object = object;
+ printf("got object (%d)\n", *p);
+ p++;
+ break;
+ case WL_ARGUMENT_NEW_ID:
+ types[i + 2] = &ffi_type_uint32;
+ values[i + 2].new_id = *p;
+ object = wl_hash_lookup(&client->display->objects, *p);
+ if (object != NULL)
+ printf("object already exists (%d)\n", *p);
+ printf("got new_id (%d)\n", *p);
+ p++;
+ break;
+ default:
+ printf("unknown type\n");
+ break;
+ }
+ args[i + 2] = &values[i + 2];
+ }
+
+ ffi_prep_cif(&cif, FFI_DEFAULT_ABI, method->argument_count + 2,
+ &ffi_type_uint32, types);
+ ffi_call(&cif, FFI_FN(method->func), &result, args);
+}
+
+static void
+wl_client_data(int fd, uint32_t mask, void *data)
+{
+ struct wl_client *client = data;
+ struct wl_object *object;
+ const struct wl_method *method;
+ char buffer[256];
+ uint32_t *p;
+ int len;
+
+ if (mask & WL_EVENT_READABLE) {
+ len = read(fd, buffer, sizeof buffer);
+ if (len == 0) {
+ wl_client_destroy(client);
+ } else {
+ printf("got %d bytes from client %p\n",
+ len, client);
+ if (len < 2 * sizeof *p)
+ /* read more... */
+ return;
+
+ p = (uint32_t *) buffer;
+ object = wl_hash_lookup(&client->display->objects,
+ p[0]);
+ if (object == NULL) {
+ /* send error */
+ printf("invalid object\n");
+ return;
+ }
+
+ if (p[1] >= object->interface->method_count) {
+ /* send error */
+ printf("invalid method\n");
+ return;
+ }
+
+ method = &object->interface->methods[p[1]];
+ printf("calling method %s on interface %s\n",
+ method->name, object->interface->name);
+ demarshal(client, object, method, p + 2, len - 8);
+ }
+ }
+
+ if (mask & WL_EVENT_WRITEABLE) {
+ }
+}
+
+static void
+wl_display_get_interface(struct wl_client *client,
+ struct wl_display *display,
+ const char *interface, uint32_t id)
+{
+ /* client sends a new object id, and an interface identifier
+ * to name the object that implements the interface */
+ printf("display::get_interface\n");
+}
+
+static int
+wl_display_create_surface(struct wl_client *client,
+ struct wl_display *display, uint32_t id)
+{
+ struct wl_surface *surface;
+
+ printf("display::create_surface, client %p, display %p, new_id=%d\n",
+ client, display, id);
+
+ surface = wl_surface_create(display, id);
+ wl_hash_insert(&display->objects, &surface->base);
+
+ return 0;
+}
+
+static const struct wl_argument create_surface_arguments[] = {
+ { WL_ARGUMENT_NEW_ID }
+};
+
+static const struct wl_method display_methods[] = {
+ { "get_interface", wl_display_get_interface,
+ ARRAY_LENGTH(get_interface_arguments), get_interface_arguments },
+ { "create_surface", wl_display_create_surface,
+ ARRAY_LENGTH(create_surface_arguments), create_surface_arguments },
+};
+
+static const struct wl_interface display_interface = {
+ "display", 1, ARRAY_LENGTH(display_methods), display_methods,
+};
+
+struct wl_display *
+wl_display_create(void)
+{
+ struct wl_display *display;
+
+ display = malloc(sizeof *display);
+ if (display == NULL)
+ return NULL;
+
+ display->loop = wl_event_loop_create();
+ if (display->loop == NULL) {
+ free(display);
+ return NULL;
+ }
+
+ display->base.id = 0;
+ display->base.interface = &display_interface;
+ wl_hash_insert(&display->objects, &display->base);
+
+ return display;
+}
+
+void
+wl_display_run(struct wl_display *display)
+{
+ while (1)
+ wl_event_loop_wait(display->loop);
+}
+
+/* The plan here is to generate a random anonymous socket name and
+ * advertise that through a service on the session dbus.
+ */
+static const char socket_name[] = "\0wayland";
+
+static void
+socket_data(int fd, uint32_t mask, void *data)
+{
+ struct wl_display *display = data;
+ struct sockaddr_un name;
+ socklen_t length;
+ int client_fd;
+
+ length = sizeof name;
+ client_fd = accept (fd, (struct sockaddr *) &name, &length);
+ if (client_fd < 0)
+ fprintf(stderr, "failed to accept\n");
+
+ wl_client_create(display, client_fd);
+}
+
+int
+wl_display_add_socket(struct wl_display *display)
+{
+ struct sockaddr_un name;
+ int sock;
+ socklen_t size;
+
+ sock = socket(PF_LOCAL, SOCK_STREAM, 0);
+ if (sock < 0)
+ return -1;
+
+ name.sun_family = AF_LOCAL;
+ memcpy(name.sun_path, socket_name, sizeof socket_name);
+
+ size = offsetof (struct sockaddr_un, sun_path) + sizeof socket_name;
+ if (bind(sock, (struct sockaddr *) &name, size) < 0)
+ return -1;
+
+ if (listen(sock, 1) < 0)
+ return -1;
+
+ wl_event_loop_add_fd(display->loop, sock, WL_EVENT_READABLE,
+ socket_data, display);
+
+ return 0;
+}
+
+
+int main(int argc, char *argv[])
+{
+ struct wl_display *display;
+
+ display = wl_display_create();
+
+ if (wl_display_add_socket(display)) {
+ fprintf(stderr, "failed to add socket: %m\n");
+ exit(EXIT_FAILURE);
+ }
+
+ printf("wayland online, display is %p\n", display);
+
+ wl_display_run(display);
+
+ return 0;
+}