commit 9605f2f9c263f39897728ace0eed58ccd80a0349
author Tom Sepez <tsepez@chromium.org> Sat Aug 27 00:19:42 2022 +0000
committer Pdfium LUCI CQ <pdfium-scoped@luci-project-accounts.iam.gserviceaccount.com> Sat Aug 27 00:19:42 2022 +0000
tree 55a6b267d05599a0d8ba837a1641ccc179b3de2b
parent ee2616e99523ccc703786a0f6ccfbcad1268e741

Vastly simplify CPDF_Type3Cache::m_SizeMap

Use a compound key of four ints rather than cobbling together a
string in an ad-hoc manner. Avoids pointer arithmetic as a
consequence.

Change-Id: I354bcbdaf2a4fd47ecf4eb81dd969616c0e99696
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/96954
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Tom Sepez <tsepez@chromium.org>

core/fpdfapi/render/cpdf_type3cache.cpp

diff --git a/core/fpdfapi/render/cpdf_type3cache.cpp b/core/fpdfapi/render/cpdf_type3cache.cpp
index 78c149b..dbb3e87 100644
--- a/core/fpdfapi/render/cpdf_type3cache.cpp
+++ b/core/fpdfapi/render/cpdf_type3cache.cpp
@@ -7,7 +7,6 @@
 #include "core/fpdfapi/render/cpdf_type3cache.h"
 
 #include <math.h>
-#include <stdarg.h>
 
 #include <memory>
 #include <utility>
@@ -23,24 +22,6 @@
 
 namespace {
 
-struct UniqueKeyGen {
-  void Generate(int count, ...);
-
-  int m_KeyLen;
-  char m_Key[128];
-};
-
-void UniqueKeyGen::Generate(int count, ...) {
-  va_list argList;
-  va_start(argList, count);
-  for (int i = 0; i < count; i++) {
-    int p = va_arg(argList, int);
-    (reinterpret_cast<uint32_t*>(m_Key))[i] = p;
-  }
-  va_end(argList);
-  m_KeyLen = count * sizeof(uint32_t);
-}
-
 bool IsScanLine1bpp(const uint8_t* pBuf, int width) {
   int size = width / 8;
   for (int i = 0; i < size; i++) {
@@ -98,17 +79,18 @@
 
 const CFX_GlyphBitmap* CPDF_Type3Cache::LoadGlyph(uint32_t charcode,
                                                   const CFX_Matrix& mtMatrix) {
-  UniqueKeyGen keygen;
-  keygen.Generate(
-      4, FXSYS_roundf(mtMatrix.a * 10000), FXSYS_roundf(mtMatrix.b * 10000),
-      FXSYS_roundf(mtMatrix.c * 10000), FXSYS_roundf(mtMatrix.d * 10000));
-  ByteString FaceGlyphsKey(keygen.m_Key, keygen.m_KeyLen);
+  SizeKey keygen = {
+      FXSYS_roundf(mtMatrix.a * 10000),
+      FXSYS_roundf(mtMatrix.b * 10000),
+      FXSYS_roundf(mtMatrix.c * 10000),
+      FXSYS_roundf(mtMatrix.d * 10000),
+  };
   CPDF_Type3GlyphMap* pSizeCache;
-  auto it = m_SizeMap.find(FaceGlyphsKey);
+  auto it = m_SizeMap.find(keygen);
   if (it == m_SizeMap.end()) {
     auto pNew = std::make_unique<CPDF_Type3GlyphMap>();
     pSizeCache = pNew.get();
-    m_SizeMap[FaceGlyphsKey] = std::move(pNew);
+    m_SizeMap[keygen] = std::move(pNew);
   } else {
     pSizeCache = it->second.get();
   }

core/fpdfapi/render/cpdf_type3cache.h

diff --git a/core/fpdfapi/render/cpdf_type3cache.h b/core/fpdfapi/render/cpdf_type3cache.h
index 7121327..d85387b 100644
--- a/core/fpdfapi/render/cpdf_type3cache.h
+++ b/core/fpdfapi/render/cpdf_type3cache.h
@@ -11,6 +11,7 @@
 
 #include <map>
 #include <memory>
+#include <tuple>
 
 #include "core/fxcrt/bytestring.h"
 #include "core/fxcrt/observed_ptr.h"
@@ -29,6 +30,8 @@
                                    const CFX_Matrix& mtMatrix);
 
  private:
+  using SizeKey = std::tuple<int, int, int, int>;
+
   explicit CPDF_Type3Cache(CPDF_Type3Font* pFont);
   ~CPDF_Type3Cache() override;
 
@@ -37,7 +40,7 @@
                                                const CFX_Matrix& mtMatrix);
 
   RetainPtr<CPDF_Type3Font> const m_pFont;
-  std::map<ByteString, std::unique_ptr<CPDF_Type3GlyphMap>> m_SizeMap;
+  std::map<SizeKey, std::unique_ptr<CPDF_Type3GlyphMap>> m_SizeMap;
 };
 
 #endif  // CORE_FPDFAPI_RENDER_CPDF_TYPE3CACHE_H_