Fix up wayland client implementation

Now it receives frame callbacks and renders properly, and is double
buffered and such.

2 files changed, 140 insertions, 89 deletions

diff --git a/wayland/buffers.c b/wayland/buffers.c
new file mode 100644
index 00000000..13193423
--- /dev/null
+++ b/wayland/buffers.c
@@ -0,0 +1,116 @@
+#include <wayland-client.h>
+#include <cairo/cairo.h>
+#include <pango/pangocairo.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <errno.h>
+#include <sys/mman.h>
+#include "client/buffer.h"
+#include "list.h"
+#include "log.h"
+
+static int create_pool_file(size_t size) {
+    static const char template[] = "/sway-client-XXXXXX";
+    const char *path = getenv("XDG_RUNTIME_DIR");
+        if (!path) {
+        return -1;
+    }
+
+    int ts = (path[strlen(path) - 1] == '/');
+
+    char *name = malloc(
+                strlen(template) +
+                strlen(path) +
+                (ts ? 1 : 0) + 1);
+        sprintf(name, "%s%s%s", path, ts ? "" : "/", template);
+
+    int fd = mkstemp(name);
+    free(name);
+
+    if (fd < 0) {
+        return -1;
+    }
+
+    if (ftruncate(fd, size) < 0) {
+        close(fd);
+        return -1;
+    }
+
+    return fd;
+}
+
+static void buffer_release(void *data, struct wl_buffer *wl_buffer) {
+        struct buffer *buffer = data;
+        buffer->busy = false;
+}
+
+static const struct wl_buffer_listener buffer_listener = {
+        .release = buffer_release
+};
+
+static struct buffer *create_buffer(struct client_state *state, struct buffer *buf,
+                int32_t width, int32_t height, uint32_t format) {
+
+        uint32_t stride = width * 4;
+        uint32_t size = stride * height;
+
+        int fd = create_pool_file(size);
+        void *data = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+        struct wl_shm_pool *pool = wl_shm_create_pool(state->shm, fd, size);
+        buf->buffer = wl_shm_pool_create_buffer(pool, 0, width, height, stride, format);
+        wl_shm_pool_destroy(pool);
+        close(fd);
+        fd = -1;
+
+        buf->surface = cairo_image_surface_create_for_data(data, CAIRO_FORMAT_ARGB32, width, height, stride);
+        buf->cairo = cairo_create(buf->surface);
+        buf->pango = pango_cairo_create_context(buf->cairo);
+
+        wl_buffer_add_listener(buf->buffer, &buffer_listener, state);
+        return buf;
+}
+
+static void destroy_buffer(struct buffer *buffer) {
+    if (buffer->buffer) {
+        wl_buffer_destroy(buffer->buffer);
+    }
+    if (buffer->cairo) {
+        cairo_destroy(buffer->cairo);
+    }
+    if (buffer->surface) {
+        cairo_surface_destroy(buffer->surface);
+    }
+    memset(buffer, 0, sizeof(struct buffer));
+}
+
+struct buffer *get_next_buffer(struct client_state *state) {
+    struct buffer *buffer = NULL;
+
+    int i;
+    for (i = 0; i < 2; ++i) {
+        if (state->buffers[i].busy) {
+            continue;
+        }
+        buffer = &state->buffers[i];
+    }
+
+    if (!buffer) {
+        return NULL;
+    }
+
+    if (buffer->width != state->width || buffer->height != state->height) {
+        destroy_buffer(buffer);
+    }
+
+    if (!buffer->buffer) {
+        if (!create_buffer(state, buffer, state->width, state->height, WL_SHM_FORMAT_ARGB8888)) {
+            return NULL;
+        }
+    }
+    
+    state->cairo = buffer->cairo;
+    state->buffer = buffer;
+    return buffer;
+}
diff --git a/wayland/client.c b/wayland/client.c
index fcbba885..4d4a6bbb 100644
--- a/wayland/client.c
+++ b/wayland/client.c
@@ -7,7 +7,8 @@
 #include <unistd.h>
 #include <errno.h>
 #include <sys/mman.h>
-#include "client.h"
+#include "client/client.h"
+#include "client/buffer.h"
 #include "list.h"
 #include "log.h"
 
@@ -73,87 +74,12 @@ static const struct wl_registry_listener registry_listener = {
         .global_remove = registry_global_remove
 };
 
-static int create_pool_file(size_t size) {
-    static const char template[] = "/swaybg-XXXXXX";
-    const char *path = getenv("XDG_RUNTIME_DIR");
-        if (!path) {
-        return -1;
-    }
-
-    int ts = (path[strlen(path) - 1] == '/');
-
-    char *name = malloc(
-                strlen(template) +
-                strlen(path) +
-                (ts ? 1 : 0) + 1);
-        sprintf(name, "%s%s%s", path, ts ? "" : "/", template);
-
-    int fd = mkstemp(name);
-    free(name);
-
-    if (fd < 0) {
-        return -1;
-    }
-
-    if (ftruncate(fd, size) < 0) {
-        close(fd);
-        return -1;
-    }
-
-    return fd;
-}
-
-static void buffer_release(void *data, struct wl_buffer *buffer) {
-        struct client_state *state = data;
-        state->busy = false;
-        sway_log(L_INFO, "buffer release");
-}
-
-static const struct wl_buffer_listener buffer_listener = {
-        .release = buffer_release
-};
-
-struct buffer *create_buffer(struct client_state *state,
-                int32_t width, int32_t height, uint32_t format) {
-
-        struct buffer *buf = malloc(sizeof(struct buffer));
-        memset(buf, 0, sizeof(struct buffer));
-        uint32_t stride = width * 4;
-        uint32_t size = stride * height;
-
-        int fd = create_pool_file(size);
-        void *data = mmap(NULL, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
-        buf->pool = wl_shm_create_pool(state->shm, fd, size);
-        buf->buffer = wl_shm_pool_create_buffer(buf->pool, 0, width, height, stride, format);
-        wl_shm_pool_destroy(buf->pool);
-        close(fd);
-        fd = -1;
-
-        state->cairo_surface = cairo_image_surface_create_for_data(data, CAIRO_FORMAT_ARGB32, width, height, stride);
-        state->cairo = cairo_create(state->cairo_surface);
-        state->pango = pango_cairo_create_context(state->cairo);
-
-        wl_buffer_add_listener(buf->buffer, &buffer_listener, state);
-
-        sway_log(L_INFO, "%p %p", buf->pool, buf->buffer);
-        return buf;
-}
-
-static void frame_callback(void *data, struct wl_callback *callback, uint32_t time) {
-        sway_log(L_INFO, "frame callback");
-        struct client_state *state = data;
-        wl_callback_destroy(callback);
-        state->frame_cb = NULL;
-}
-
-static const struct wl_callback_listener listener = {
-        frame_callback
-};
-
-struct client_state *client_setup(void) {
+struct client_state *client_setup(uint32_t width, uint32_t height) {
         struct client_state *state = malloc(sizeof(struct client_state));
         memset(state, 0, sizeof(struct client_state));
         state->outputs = create_list();
+        state->width = width;
+        state->height = height;
 
         state->display = wl_display_connect(NULL);
         if (!state->display) {
@@ -168,22 +94,33 @@ struct client_state *client_setup(void) {
         wl_display_roundtrip(state->display);
         wl_registry_destroy(registry);
 
-        state->buffer = create_buffer(state, 100, 100, WL_SHM_FORMAT_ARGB8888);
         state->surface = wl_compositor_create_surface(state->compositor);
         state->shell_surface = wl_shell_get_shell_surface(state->shell, state->surface);
         wl_shell_surface_set_toplevel(state->shell_surface);
 
-        wl_surface_damage(state->surface, 0, 0, 100, 100);
-
         return state;
 }
 
-int client_render(struct client_state *state) {
-        if (state->frame_cb || state->busy) {
-                return 2;
+static void frame_callback(void *data, struct wl_callback *callback, uint32_t time) {
+        struct client_state *state = data;
+        wl_callback_destroy(callback);
+        state->frame_cb = NULL;
+}
+
+static const struct wl_callback_listener listener = {
+        frame_callback
+};
+
+int client_prerender(struct client_state *state) {
+        if (state->frame_cb) {
+                return 0;
         }
-        sway_log(L_INFO, "Rendering");
 
+        get_next_buffer(state);
+        return 1;
+}
+
+int client_render(struct client_state *state) {
         state->frame_cb = wl_surface_frame(state->surface);
         wl_callback_add_listener(state->frame_cb, &listener, state);
 
@@ -191,9 +128,7 @@ int client_render(struct client_state *state) {
         wl_surface_attach(state->surface, state->buffer->buffer, 0, 0);
         wl_surface_commit(state->surface);
 
-        state->busy = true;
-
-        return wl_display_dispatch(state->display) != -1;
+        return 1;
 }
 
 void client_teardown(struct client_state *state) {