Set an upper limit to the number of characters that can appear in a tooltip s...

chrome/views/tooltip_manager.cc

 // Copyright (c) 2006-2008 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 <limits>
 
 #include "chrome/common/gfx/chrome_font.h"
 #include "base/logging.h"
 #include "base/message_loop.h"
 #include "chrome/common/l10n_util.h"
 #include "chrome/common/gfx/url_elider.h"
 #include "chrome/common/win_util.h"
 #include "chrome/views/root_view.h"
 #include "chrome/views/tooltip_manager.h"
 #include "chrome/views/view.h"
 #include "chrome/views/view_container.h"
 
 namespace ChromeViews {
 
 //static
 int TooltipManager::tooltip_height_ = 0;
 
 // Default timeout for the tooltip displayed using keyboard.
 // Timeout is mentioned in milliseconds.
 static const int kDefaultTimeout = 4000;
 
 // Maximum number of lines we allow in the tooltip.
 static const int kMaxLines = 6;
 
+// Maximum number of characters we allow in a tooltip.
+static const int kMaxTooltipLength = 1024;
+
 // Breaks |text| along line boundaries, placing each line of text into lines.
 static void SplitTooltipString(const std::wstring& text,
                                std::vector<std::wstring>* lines) {
   size_t index = 0;
   size_t next_index;
   while ((next_index = text.find(TooltipManager::GetLineSeparator(), index))
          != std::wstring::npos && lines->size() < kMaxLines) {
     lines->push_back(text.substr(index, next_index - index));
     index = next_index + TooltipManager::GetLineSeparator().size();
   }
@@ skipping 225 matching lines @@
 
 void TooltipManager::TrimTooltipToFit(std::wstring* text,
                                       int* max_width,
                                       int* line_count,
                                       int position_x,
                                       int position_y,
                                       HWND window) {
   *max_width = 0;
   *line_count = 0;
 
+  // Clamp the tooltip length to kMaxTooltipLength so that we don't
+  // accidentally DOS the user with a mega tooltip (since Windows doesn't seem
+  // to do this itself).
+  if (text->length() > kMaxTooltipLength)
+    *text = text->substr(0, kMaxTooltipLength);
+
   // Determine the available width for the tooltip.
   CPoint screen_loc(position_x, position_y);
   View::ConvertPointToScreen(view_container_->GetRootView(), &screen_loc);
   gfx::Rect monitor_bounds =
       win_util::GetMonitorBoundsForRect(gfx::Rect(screen_loc.x, screen_loc.y,
                                                   0, 0));
   RECT tooltip_margin;
   SendMessage(window, TTM_GETMARGIN, 0, (LPARAM)&tooltip_margin);
   const int available_width = monitor_bounds.width() - tooltip_margin.left -
       tooltip_margin.right;
@@ skipping 128 matching lines @@
     keyboard_tooltip_hwnd_ = NULL;
   }
 }
 
 void TooltipManager::DestroyKeyboardTooltipWindow(HWND window_to_destroy) {
   if (keyboard_tooltip_hwnd_ == window_to_destroy)
     HideKeyboardTooltip();
 }
 
 } // namespace ChromeViews