From abfdb53f6d111eb6d44e7ee3c8573e325b93efb4 Mon Sep 17 00:00:00 2001
From: gyzhou <gyzhou@chromium.org>
Date: Mon, 13 Jun 2016 09:22:03 -0700
Subject: [PATCH] Fixed partially out of screen window capture in unix

BUG=596595

Review-Url: https://codereview.webrtc.org/2044693002
Cr-Commit-Position: refs/heads/master@{#13113}
---
 .../desktop_capture/x11/x_server_pixel_buffer.cc    | 12 +++++-------
 .../desktop_capture/x11/x_server_pixel_buffer.h     | 13 +++++++------
 2 files changed, 12 insertions(+), 13 deletions(-)

diff --git a/webrtc/modules/desktop_capture/x11/x_server_pixel_buffer.cc b/webrtc/modules/desktop_capture/x11/x_server_pixel_buffer.cc
index bcfcb7e027..b99763950e 100644
--- a/webrtc/modules/desktop_capture/x11/x_server_pixel_buffer.cc
+++ b/webrtc/modules/desktop_capture/x11/x_server_pixel_buffer.cc
@@ -59,11 +59,7 @@ bool IsXImageRGBFormat(XImage* image) {
 
 namespace webrtc {
 
-XServerPixelBuffer::XServerPixelBuffer()
-    : display_(NULL), window_(0),
-      x_image_(NULL),
-      shm_segment_info_(NULL), shm_pixmap_(0), shm_gc_(NULL) {
-}
+XServerPixelBuffer::XServerPixelBuffer() {}
 
 XServerPixelBuffer::~XServerPixelBuffer() {
   Release();
@@ -229,7 +225,9 @@ void XServerPixelBuffer::Synchronize() {
   if (shm_segment_info_ && !shm_pixmap_) {
     // XShmGetImage can fail if the display is being reconfigured.
     XErrorTrap error_trap(display_);
-    XShmGetImage(display_, window_, x_image_, 0, 0, AllPlanes);
+    // XShmGetImage fails if the window is partially out of screen.
+    xshm_get_image_succeeded_ =
+        XShmGetImage(display_, window_, x_image_, 0, 0, AllPlanes);
   }
 }
 
@@ -240,7 +238,7 @@ void XServerPixelBuffer::CaptureRect(const DesktopRect& rect,
 
   uint8_t* data;
 
-  if (shm_segment_info_) {
+  if (shm_segment_info_ && (shm_pixmap_ || xshm_get_image_succeeded_)) {
     if (shm_pixmap_) {
       XCopyArea(display_, window_, shm_pixmap_, shm_gc_,
                 rect.left(), rect.top(), rect.width(), rect.height(),
diff --git a/webrtc/modules/desktop_capture/x11/x_server_pixel_buffer.h b/webrtc/modules/desktop_capture/x11/x_server_pixel_buffer.h
index b868b044a8..b202abb9bc 100644
--- a/webrtc/modules/desktop_capture/x11/x_server_pixel_buffer.h
+++ b/webrtc/modules/desktop_capture/x11/x_server_pixel_buffer.h
@@ -70,13 +70,14 @@ class XServerPixelBuffer {
                 const DesktopRect& rect,
                 DesktopFrame* frame);
 
-  Display* display_;
-  Window window_;
+  Display* display_ = nullptr;
+  Window window_ = 0;
   DesktopSize window_size_;
-  XImage* x_image_;
-  XShmSegmentInfo* shm_segment_info_;
-  Pixmap shm_pixmap_;
-  GC shm_gc_;
+  XImage* x_image_ = nullptr;
+  XShmSegmentInfo* shm_segment_info_ = nullptr;
+  Pixmap shm_pixmap_ = 0;
+  GC shm_gc_ = nullptr;
+  bool xshm_get_image_succeeded_ = false;
 
   RTC_DISALLOW_COPY_AND_ASSIGN(XServerPixelBuffer);
 };