exo: produce libwayland-client.so

components/exo/wayland/client_demo/wayland_client_demo.cc

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <fcntl.h>
+#include <string.h>
+#include <unistd.h>
+#include <wayland-client.h>
+
+#include <memory>
+#include <sys/mman.h>
+
+namespace {
+
+class WaylandClient {
+ public:
+  static WaylandClient* Create() {
+    std::unique_ptr<WaylandClient> client(new WaylandClient);
+    if (client->Initialize())
+      return client.release();
+    return nullptr;
+  }
+
+  ~WaylandClient() {
+    wl_pointer_destroy(pointer_);
+    wl_seat_destroy(seat_);
+    wl_shell_destroy(shell_);
+    wl_shm_destroy(shm_);
+    wl_compositor_destroy(compositor_);
+    wl_display_disconnect(display_);
+  }
+
+  bool running() const { return running_; }
+  struct wl_compositor* compositor() const {
+    return compositor_;
+  }
+  struct wl_display* display() const {
+    return display_;
+  }
+  struct wl_shell* shell() const {
+    return shell_;
+  }
+  struct wl_shm* shm() const {
+    return shm_;
+  }
+
+ private:
+  WaylandClient() {}
+  WaylandClient(const WaylandClient&) = delete;
+  void operator=(const WaylandClient&) = delete;
+
+  bool Initialize() {
+    display_ = wl_display_connect(nullptr);
+    if (!display_) {
+      perror("Cannot open display");
+      return false;
+    }
+
+    struct wl_registry* registry = wl_display_get_registry(display_);
+    const struct wl_registry_listener registry_listener = {
+        WaylandClient::OnRegistry, WaylandClient::OnRemoveRegistry};
+    wl_registry_add_listener(registry, &registry_listener, this);
+    wl_display_roundtrip(display_);
+    wl_registry_destroy(registry);
+    running_ = true;
+
+    return true;
+  }
+
+  static void OnRemoveRegistry(void* a, struct wl_registry* b, uint32_t c) {}
+
+  static void OnRegistry(void* data,
+                         struct wl_registry* registry,
+                         uint32_t name,
+                         const char* interface,
+                         uint32_t version) {
+    WaylandClient* me = static_cast<WaylandClient*>(data);
+    if (!strcmp(interface, wl_compositor_interface.name)) {
+      me->compositor_ = static_cast<wl_compositor*>(
+          wl_registry_bind(registry, name, &wl_compositor_interface, version));
+    } else if (!strcmp(interface, wl_shm_interface.name)) {
+      me->shm_ = static_cast<wl_shm*>(
+          wl_registry_bind(registry, name, &wl_shm_interface, version));
+    } else if (!strcmp(interface, wl_shell_interface.name)) {
+      me->shell_ = static_cast<wl_shell*>(
+          wl_registry_bind(registry, name, &wl_shell_interface, version));
+    } else if (!strcmp(interface, wl_seat_interface.name)) {
+      me->seat_ = static_cast<wl_seat*>(
+          wl_registry_bind(registry, name, &wl_seat_interface, version));
+      me->pointer_ = wl_seat_get_pointer(me->seat_);
+      const struct wl_pointer_listener pointer_listener = {
+          OnPointerEnter, OnPointerLeave, OnPointerMotion, OnPointerButton,
+          OnPointerAxis};
+      wl_pointer_add_listener(me->pointer_, &pointer_listener, data);
+    }
+  }
+
+  static void OnPointerEnter(void* data,
+                             struct wl_pointer* wl_pointer,
+                             uint32_t serial,
+                             struct wl_surface* surface,
+                             wl_fixed_t surface_x,
+                             wl_fixed_t surface_y) {}
+  static void OnPointerLeave(void* data,
+                             struct wl_pointer* wl_pointer,
+                             uint32_t serial,
+                             struct wl_surface* wl_surface) {}
+
+  static void OnPointerMotion(void* data,
+                              struct wl_pointer* wl_pointer,
+                              uint32_t time,
+                              wl_fixed_t surface_x,
+                              wl_fixed_t surface_y) {}
+
+  // Program exits if clicking any mouse buttons.
+  static void OnPointerButton(void* data,
+                              struct wl_pointer* wl_pointer,
+                              uint32_t serial,
+                              uint32_t time,
+                              uint32_t button,
+                              uint32_t state) {
+    WaylandClient* me = static_cast<WaylandClient*>(data);
+    me->running_ = false;
+  }
+
+  static void OnPointerAxis(void* data,
+                            struct wl_pointer* wl_pointer,
+                            uint32_t time,
+                            uint32_t axis,
+                            wl_fixed_t value) {}
+
+  bool running_ = false;
+  struct wl_compositor* compositor_ = nullptr;
+  struct wl_display* display_ = nullptr;
+  struct wl_pointer* pointer_ = nullptr;
+  struct wl_seat* seat_ = nullptr;
+  struct wl_shell* shell_ = nullptr;
+  struct wl_shm* shm_ = nullptr;
+};
+
+class DemoWindow {
+ public:
+  DemoWindow() {}
+  ~DemoWindow() {
+    wl_buffer_destroy(buffer_);
+    wl_shell_surface_destroy(shell_surface_);
+    wl_surface_destroy(surface_);
+  }
+
+  int Run() {
+    client_.reset(WaylandClient::Create());
+    if (!client_) {
+      perror("Cannot create WaylandClient");
+      return EXIT_FAILURE;
+    }
+
+    if (!CreateBuffer()) {
+      perror("Creating a buffer failed");
+      return EXIT_FAILURE;
+    }
+
+    if (!CreateSurface()) {
+      perror("Creating a surface failed");
+      return EXIT_FAILURE;
+    }
+
+    Redraw(this, nullptr, 0);
+    int ret = 0;
+    while (client_->running() && ret != -1)
+      ret = wl_display_dispatch(client_->display());
+
+    return EXIT_SUCCESS;
+  }
+
+ private:
+  DemoWindow(const DemoWindow&) = delete;
+  void operator=(const DemoWindow&) = delete;
+
+  bool CreateBuffer() {
+    int stride = WIDTH * 4;
+    int size = stride * HEIGHT;
+    ScopedFD fd(CreateAnonymousFile(size));
+    if (fd.Get() < 0) {
+      perror("Creating a buffer file failed");
+      return false;
+    }
+    data_ =
+        mmap(nullptr, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd.Get(), 0);
+    if (data_ == MAP_FAILED) {
+      perror("mmap failed");
+      return false;
+    }
+
+    struct wl_shm_pool* pool =
+        wl_shm_create_pool(client_->shm(), fd.Get(), size);
+    buffer_ = wl_shm_pool_create_buffer(pool, 0, WIDTH, HEIGHT, stride,
+                                        WL_SHM_FORMAT_XRGB8888);
+    wl_shm_pool_destroy(pool);
+    return true;
+  }
+
+  class ScopedFD {
+   public:
+    explicit ScopedFD(int fd) : fd_(fd) {}
+    ~ScopedFD() {
+      if (auto_close_)
+        close(fd_);
+    }
+    int Get() { return fd_; }
+    int Release() {
+      auto_close_ = false;
+      return fd_;
+    }
+
+   private:
+    ScopedFD(const ScopedFD&) = delete;
+    void operator=(const ScopedFD&) = delete;
+
+    const int fd_;
+    bool auto_close_ = true;
+  };
+
+  int CreateAnonymousFile(off_t size) {
+    static const std::string file_name = "/weston-shared-XXXXXX";
+    const std::string path = getenv("XDG_RUNTIME_DIR");
+    if (path.empty()) {
+      errno = ENOENT;
+      return -1;
+    }
+
+    std::string name = path + file_name;
+    char* c_name = const_cast<char*>(name.data());
+    ScopedFD fd(mkstemp(c_name));
+    if (fd.Get() < 0)
+      return -1;
+
+    long flags = fcntl(fd.Get(), F_GETFD);
+    if (flags == -1)
+      return -1;
+    if (fcntl(fd.Get(), F_SETFD, flags | FD_CLOEXEC) == -1)
+      return -1;
+    if (ftruncate(fd.Get(), size) < 0)
+      return -1;
+
+    return fd.Release();
+  }
+
+  bool CreateSurface() {
+    surface_ = wl_compositor_create_surface(client_->compositor());
+    if (!surface_)
+      return false;
+
+    shell_surface_ = wl_shell_get_shell_surface(client_->shell(), surface_);
+    if (!shell_surface_) {
+      wl_surface_destroy(surface_);
+      return false;
+    }
+
+    wl_shell_surface_set_toplevel(shell_surface_);
+    wl_shell_surface_set_user_data(shell_surface_, surface_);
+    wl_surface_set_user_data(surface_, nullptr);
+    return true;
+  }
+
+  static void Redraw(void* data, struct wl_callback* callback, uint32_t time) {
+    DemoWindow* me = static_cast<DemoWindow*>(data);
+
+    PaintPixels(me->data_, 20, WIDTH, HEIGHT, time);
+
+    const int border_width = 20;
+    wl_surface_attach(me->surface_, me->buffer_, 0, 0);
+    wl_surface_damage(me->surface_, border_width, border_width,
+                      WIDTH - 2 * border_width, HEIGHT - 2 * border_width);
+    if (callback)
+      wl_callback_destroy(callback);
+    me->callback_ = wl_surface_frame(me->surface_);
+    const struct wl_callback_listener frame_listener = {Redraw};
+    wl_callback_add_listener(me->callback_, &frame_listener, me);
+    wl_surface_commit(me->surface_);
+  }
+
+  // Copied from
+  // https://cgit.freedesktop.org/wayland/weston/tree/clients/simple-shm.c
+  // which is in MIT license.
+  static void PaintPixels(void* image,
+                          int padding,
+                          int width,
+                          int height,
+                          uint32_t time) {
+    uint32_t* pixel = static_cast<uint32_t*>(image);
+    const int halfh = padding + (height - padding * 2) / 2;
+    const int halfw = padding + (width - padding * 2) / 2;
+
+    /* squared radii thresholds */
+    int outr = (halfw < halfh ? halfw : halfh) - 8;
+    int inr = outr - 32;
+    outr *= outr;
+    inr *= inr;
+
+    pixel += padding * width;
+    for (int y = padding; y < height - padding; y++) {
+      int y2 = (y - halfh) * (y - halfh);
+      pixel += padding;
+      for (int x = padding; x < width - padding; x++) {
+        uint32_t v;
+
+        /* squared distance from center */
+        int r2 = (x - halfw) * (x - halfw) + y2;
+
+        if (r2 < inr)
+          v = (r2 / 32 + time / 64) * 0x0080401;
+        else if (r2 < outr)
+          v = (y + time / 32) * 0x0080401;
+        else
+          v = (x + time / 16) * 0x0080401;
+        v &= 0x00ffffff;
+
+        /* cross if compositor uses X from XRGB as alpha */
+        if (abs(x - y) > 6 && abs(x + y - height) > 6)
+          v |= 0xff000000;
+
+        *pixel++ = v;
+      }
+
+      pixel += padding;
+    }
+  }
+
+  static const unsigned WIDTH = 300;
+  static const unsigned HEIGHT = 300;
+
+  std::unique_ptr<WaylandClient> client_;
+  struct wl_shell_surface* shell_surface_ = nullptr;
+  struct wl_surface* surface_ = nullptr;
+  struct wl_buffer* buffer_ = nullptr;
+  void* data_ = nullptr;
+  struct wl_callback* callback_ = nullptr;
+};
+
+}  // namespace
+
+int main(int argc, char** argv) {
+  std::unique_ptr<DemoWindow> window(new DemoWindow);
+  return window->Run();
+}