send the pngs on cros

Added code to stream screenshots

gtk screenshot support

Review URL: http://codereview.chromium.org/517017

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@35317 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 48 insertions, 0 deletions

diff --git a/chrome/common/x11_util.cc b/chrome/common/x11_util.cc
index 556b804..4f8eed7 100644
--- a/chrome/common/x11_util.cc
+++ b/chrome/common/x11_util.cc
@@ -564,4 +564,52 @@ bool GetWindowManagerName(std::string* wm_name) {
   return true;
 }
 
+static cairo_status_t SnapshotCallback(
+    void *closure, const unsigned char *data, unsigned int length) {
+  std::vector<unsigned char>* png_representation =
+      static_cast<std::vector<unsigned char>*>(closure);
+
+  size_t old_size = png_representation->size();
+  png_representation->resize(old_size + length);
+  memcpy(&(*png_representation)[old_size], data, length);
+  return CAIRO_STATUS_SUCCESS;
+}
+
+void GrabWindowSnapshot(GtkWindow* gtk_window,
+                        std::vector<unsigned char>* png_representation) {
+  GdkWindow* gdk_window = GTK_WIDGET(gtk_window)->window;
+  Display* display = GDK_WINDOW_XDISPLAY(gdk_window);
+  XID win = GDK_WINDOW_XID(gdk_window);
+  XWindowAttributes attr;
+  if (XGetWindowAttributes(display, win, &attr) != 0) {
+    LOG(ERROR) << "Couldn't get window attributes";
+    return;
+  }
+  XImage* image = XGetImage(
+      display, win, 0, 0, attr.width, attr.height, AllPlanes, ZPixmap);
+  if (!image) {
+    LOG(ERROR) << "Couldn't get image";
+    return;
+  }
+  if (image->depth != 24) {
+    LOG(ERROR)<< "Unsupported image depth " << image->depth;
+    return;
+  }
+  cairo_surface_t* surface =
+      cairo_image_surface_create_for_data(
+          reinterpret_cast<unsigned char*>(image->data),
+          CAIRO_FORMAT_RGB24,
+          image->width,
+          image->height,
+          image->bytes_per_line);
+
+  if (!surface) {
+    LOG(ERROR) << "Unable to create Cairo surface from XImage data";
+    return;
+  }
+  cairo_surface_write_to_png_stream(
+      surface, SnapshotCallback, png_representation);
+  cairo_surface_destroy(surface);
+}
+
 }  // namespace x11_util