Clamp RenderTextWin layout length to 10,000 code points.

ui/gfx/render_text.h

 // Copyright (c) 2012 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.
 
 #ifndef UI_GFX_RENDER_TEXT_H_
 #define UI_GFX_RENDER_TEXT_H_
 
 #include <algorithm>
 #include <cstring>
 #include <string>
@@ skipping 175 matching lines @@
   bool obscured() const { return obscured_; }
   void SetObscured(bool obscured);
 
   // Makes a char in obscured text at |index| to be revealed. |index| should be
   // a UTF16 text index. If there is a previous revealed index, the previous one
   // is cleared and only the last set index will be revealed. If |index| is -1
   // or out of range, no char will be revealed. The revealed index is also
   // cleared when SetText or SetObscured is called.
   void SetObscuredRevealIndex(int index);
 
+  // Set the maximum length of the displayed layout text, not the actual text.
+  // A |length| of 0 forgoes a hard limit, but does not guarantee proper
+  // functionality of very long strings. Applies to subsequent SetText calls.
+  // WARNING: Only use this for system limits, it lacks complex text support.
+  void set_truncate_length(size_t length) { truncate_length_ = length; }
+
   const Rect& display_rect() const { return display_rect_; }
   void SetDisplayRect(const Rect& r);
 
   void set_fade_head(bool fade_head) { fade_head_ = fade_head; }
   bool fade_head() const { return fade_head_; }
   void set_fade_tail(bool fade_tail) { fade_tail_ = fade_tail; }
   bool fade_tail() const { return fade_tail_; }
 
   bool background_is_transparent() const { return background_is_transparent_; }
   void set_background_is_transparent(bool transparent) {
@@ skipping 199 matching lines @@
 
   // Reset the layout to be invalid.
   virtual void ResetLayout() = 0;
 
   // Ensure the text is laid out.
   virtual void EnsureLayout() = 0;
 
   // Draw the text.
   virtual void DrawVisualText(Canvas* canvas) = 0;
 
-  // Returns the text used for layout, which may be |obscured_text_|.
+  // Returns the text used for layout, which may be obscured or truncated.
   const base::string16& GetLayoutText() const;
 
   // Apply (and undo) temporary composition underlines and selection colors.
   void ApplyCompositionAndSelectionStyles();
   void UndoCompositionAndSelectionStyles();
 
   // Returns the text offset from the origin after applying text alignment and
   // display offset.
   Vector2d GetTextOffset();
 
@@ skipping 18 matching lines @@
                                  size_t caret_pos,
                                  LogicalCursorDirection caret_affinity);
 
  private:
   friend class RenderTextTest;
   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, DefaultStyle);
   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, SetColorAndStyle);
   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, ApplyColorAndStyle);
   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, ObscuredText);
   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, RevealObscuredText);
+  FRIEND_TEST_ALL_PREFIXES(RenderTextTest, TruncatedText);
+  FRIEND_TEST_ALL_PREFIXES(RenderTextTest, TruncatedObscuredText);
   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, GraphemePositions);
   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, EdgeSelectionModels);
   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, GetTextOffset);
   FRIEND_TEST_ALL_PREFIXES(RenderTextTest, GetTextOffsetHorizontalDefaultInRTL);
 
   // Set the cursor to |position|, with the caret trailing the previous
   // grapheme, or if there is no previous grapheme, leading the cursor position.
   // If |select| is false, the selection start is moved to the same position.
   // If the |position| is not a cursorable position (not on grapheme boundary),
   // it is a NO-OP.
   void MoveCursorTo(size_t position, bool select);
 
-  // Updates |obscured_text_| if the text is obscured.
-  void UpdateObscuredText();
+  // Updates |layout_text_| if the text is obscured or truncated.
+  void UpdateLayoutText();
 
   // Update the cached bounds and display offset to ensure that the current
   // cursor is within the visible display area.
   void UpdateCachedBoundsAndOffset();
 
   // Draw the selection.
   void DrawSelection(Canvas* canvas);
 
   // Logical UTF-16 string data to be drawn.
   base::string16 text_;
@@ skipping 52 matching lines @@
   // BreakList positions are stored with text indices, not layout indices.
   // TODO(msw): Expand to support cursor, selection, background, etc. colors.
   BreakList<SkColor> colors_;
   std::vector<BreakList<bool> > styles_;
 
   // Breaks saved without temporary composition and selection styling.
   BreakList<SkColor> saved_colors_;
   BreakList<bool> saved_underlines_;
   bool composition_and_selection_styles_applied_;
 
-  // A flag and the text to display for obscured (password) fields.
-  // Asterisks are used instead of the actual text glyphs when true.
+  // A flag to obscure actual text with asterisks for password fields.
   bool obscured_;
-  base::string16 obscured_text_;
-
   // The index at which the char should be revealed in the obscured text.
   int obscured_reveal_index_;
 
+  // The maximum length of text to display, 0 forgoes a hard limit.
+  size_t truncate_length_;
+
+  // The obscured and/or truncated text that will be displayed.
+  base::string16 layout_text_;
+
   // Fade text head and/or tail, if text doesn't fit into |display_rect_|.
   bool fade_head_;
   bool fade_tail_;
 
   // Is the background transparent (either partially or fully)?
   bool background_is_transparent_;
 
   // The local display area for rendering the text.
   Rect display_rect_;
 
@@ skipping 13 matching lines @@
 
   // Text shadows to be drawn.
   ShadowValues text_shadows_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderText);
 };
 
 }  // namespace gfx
 
 #endif  // UI_GFX_RENDER_TEXT_H_