Experimentally isolate GetSaveFileName in a utility process.

ui/base/win/open_file_name_win.cc

 // Copyright (c) 2014 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 "ui/base/win/open_file_name_win.h"
 
 #include "base/files/file_path.h"
 #include "base/strings/string_util.h"
+#include "base/win/windows_version.h"
 
 namespace ui {
 namespace win {
 
+namespace {
+
+// Ensures that the Save As dialog is on-screen.
+UINT_PTR CALLBACK SaveAsDialogHook(HWND dialog, UINT message,
+                                   WPARAM wparam, LPARAM lparam) {
+  static const UINT kPrivateMessage = 0x2F3F;
+  switch (message) {
+    case WM_INITDIALOG: {
+      // Do nothing here. Just post a message to defer actual processing.
+      ::PostMessage(dialog, kPrivateMessage, 0, 0);
+      return TRUE;
+    }
+    case kPrivateMessage: {
+      // The dialog box is the parent of the current handle.
+      HWND real_dialog = ::GetParent(dialog);
+
+      // Retrieve the final size.
+      RECT dialog_rect;
+      ::GetWindowRect(real_dialog, &dialog_rect);
+
+      // Verify that the upper left corner is visible.
+      POINT point = { dialog_rect.left, dialog_rect.top };
+      HMONITOR monitor1 = ::MonitorFromPoint(point, MONITOR_DEFAULTTONULL);

[sky, 2014/08/19 17:02:51]

Why not MonitorFromWindow, get the work area and constrain? Seems simpler.

[erikwright (departed), 2014/08/19 17:09:15]

I have no idea. This code is moved verbatim from its previous location (with the
exception of qualifying Win SDK functions with '::'). It seems best to keep it
as is.

+      point.x = dialog_rect.right;
+      point.y = dialog_rect.bottom;
+
+      // Verify that the lower right corner is visible.
+      HMONITOR monitor2 = ::MonitorFromPoint(point, MONITOR_DEFAULTTONULL);
+      if (monitor1 && monitor2)
+        return 0;
+
+      // Some part of the dialog box is not visible, fix it by moving is to the
+      // client rect position of the browser window.
+      HWND parent_window = ::GetParent(real_dialog);
+      if (!parent_window)
+        return 0;
+      WINDOWINFO parent_info;
+      parent_info.cbSize = sizeof(WINDOWINFO);
+      ::GetWindowInfo(parent_window, &parent_info);
+      ::SetWindowPos(
+          real_dialog,
+          NULL,
+          parent_info.rcClient.left,
+          parent_info.rcClient.top,
+          0,
+          0,  // Size.
+          SWP_NOACTIVATE | SWP_NOOWNERZORDER | SWP_NOSIZE | SWP_NOZORDER);
+
+      return 0;
+    }
+  }
+  return 0;
+}
+
+}  // namespace
+
 OpenFileName::OpenFileName(HWND parent_window, DWORD flags) {
   ::ZeroMemory(&openfilename_, sizeof(openfilename_));
   openfilename_.lStructSize = sizeof(openfilename_);
 
   // According to http://support.microsoft.com/?scid=kb;en-us;222003&x=8&y=12,
   // The lpstrFile Buffer MUST be NULL Terminated.
   filename_buffer_[0] = 0;
   openfilename_.lpstrFile = filename_buffer_;
   openfilename_.nMaxFile = arraysize(filename_buffer_);
 
@@ skipping 42 matching lines @@
 
   if (initial_filename.empty())
     return;
 
   // The filename is ignored if no initial directory is supplied.
   base::wcslcpy(filename_buffer_,
                 initial_filename.value().c_str(),
                 arraysize(filename_buffer_));
 }
 
+void OpenFileName::MaybeInstallWindowPositionHookForSaveAsOnXP() {
+  if (base::win::GetVersion() >= base::win::VERSION_VISTA)
+    return;
+
+  openfilename_.Flags |= OFN_ENABLEHOOK;
+  DCHECK(!openfilename_.lpfnHook);
+  openfilename_.lpfnHook = &SaveAsDialogHook;
+}
+
 base::FilePath OpenFileName::GetSingleResult() {
   base::FilePath directory;
   std::vector<base::FilePath> filenames;
   GetResult(&directory, &filenames);
   if (filenames.size() != 1)
     return base::FilePath();
   return directory.Append(filenames[0]);
 }
 
 void OpenFileName::GetResult(base::FilePath* directory,
@@ skipping 65 matching lines @@
         MakeTuple(base::string16(display_string, display_string_end),
                   base::string16(pattern, pattern_end)));
     display_string = pattern_end + 1;
   }
 
   return filters;
 }
 
 }  // namespace win
 }  // namespace ui