From 247c0e05dacb3b958bb7aaf06f21b93e78c43e19 Mon Sep 17 00:00:00 2001
From: Lei Zhang <thestig@chromium.org>
Date: Thu, 30 Nov 2017 18:56:00 +0000
Subject: Relax checks in CFX_FaceCache::LoadGlyphPath().

The original fix to https://crbug.com/641333 was too strict. Relax the
checks and use a std::tuple for the path map key, instead of trying to
"hash" a key.

BUG=chromium:788864

Change-Id: I6e6a96691bce2834c2e95baa16ebd39e6aa03140
Reviewed-on: https://pdfium-review.googlesource.com/19950
Reviewed-by: dsinclair <dsinclair@chromium.org>
Commit-Queue: Lei Zhang <thestig@chromium.org>
---
 core/fxge/cfx_facecache.cpp | 22 +++++++---------------
 core/fxge/cfx_facecache.h   |  5 ++++-
 2 files changed, 11 insertions(+), 16 deletions(-)

diff --git a/core/fxge/cfx_facecache.cpp b/core/fxge/cfx_facecache.cpp
index 3f037ac65a..bc29293c3a 100644
--- a/core/fxge/cfx_facecache.cpp
+++ b/core/fxge/cfx_facecache.cpp
@@ -194,23 +194,15 @@ std::unique_ptr<CFX_GlyphBitmap> CFX_FaceCache::RenderGlyph(
 const CFX_PathData* CFX_FaceCache::LoadGlyphPath(const CFX_Font* pFont,
                                                  uint32_t glyph_index,
                                                  int dest_width) {
-  if (!m_Face || glyph_index == kInvalidGlyphIndex || dest_width < 0)
+  if (!m_Face || glyph_index == kInvalidGlyphIndex)
     return nullptr;
 
-  uint32_t key = glyph_index;
-  auto* pSubstFont = pFont->GetSubstFont();
-  if (pSubstFont) {
-    if (pSubstFont->m_Weight < 0 || pSubstFont->m_ItalicAngle < 0)
-      return nullptr;
-    uint32_t weight = static_cast<uint32_t>(pSubstFont->m_Weight);
-    uint32_t angle = static_cast<uint32_t>(pSubstFont->m_ItalicAngle);
-    uint32_t key_modifier = (weight / 16) << 15;
-    key_modifier += (angle / 2) << 21;
-    key_modifier += (static_cast<uint32_t>(dest_width) / 16) << 25;
-    if (pFont->IsVertical())
-      key_modifier += 1U << 31;
-    key += key_modifier;
-  }
+  const auto* pSubstFont = pFont->GetSubstFont();
+  int weight = pSubstFont ? pSubstFont->m_Weight : 0;
+  int angle = pSubstFont ? pSubstFont->m_ItalicAngle : 0;
+  bool vertical = pSubstFont ? pFont->IsVertical() : false;
+  const PathMapKey key =
+      std::make_tuple(glyph_index, dest_width, weight, angle, vertical);
   auto it = m_PathMap.find(key);
   if (it != m_PathMap.end())
     return it->second.get();
diff --git a/core/fxge/cfx_facecache.h b/core/fxge/cfx_facecache.h
index aa98161719..a39da88b01 100644
--- a/core/fxge/cfx_facecache.h
+++ b/core/fxge/cfx_facecache.h
@@ -9,6 +9,7 @@
 
 #include <map>
 #include <memory>
+#include <tuple>
 
 #include "core/fxcrt/unowned_ptr.h"
 #include "core/fxge/fx_font.h"
@@ -42,6 +43,8 @@ class CFX_FaceCache {
 
  private:
   using SizeGlyphCache = std::map<uint32_t, std::unique_ptr<CFX_GlyphBitmap>>;
+  // <glyph_index, width, weight, angle, vertical>
+  using PathMapKey = std::tuple<uint32_t, int, int, int, bool>;
 
   std::unique_ptr<CFX_GlyphBitmap> RenderGlyph(const CFX_Font* pFont,
                                                uint32_t glyph_index,
@@ -67,7 +70,7 @@ class CFX_FaceCache {
 
   FXFT_Face const m_Face;
   std::map<ByteString, SizeGlyphCache> m_SizeMap;
-  std::map<uint32_t, std::unique_ptr<CFX_PathData>> m_PathMap;
+  std::map<PathMapKey, std::unique_ptr<CFX_PathData>> m_PathMap;
 #if defined _SKIA_SUPPORT_ || _SKIA_SUPPORT_PATHS_
   sk_sp<SkTypeface> m_pTypeface;
 #endif
-- 
cgit v1.2.3