1 files changed, 154 insertions, 0 deletions
diff --git a/core/fpdfapi/cmaps/fpdf_cmaps.cpp b/core/fpdfapi/cmaps/fpdf_cmaps.cpp
new file mode 100644
index 0000000000..c85a7d9010
--- /dev/null
+++ b/core/fpdfapi/cmaps/fpdf_cmaps.cpp
@@ -0,0 +1,154 @@
+// Copyright 2014 PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
+
+#include "core/fpdfapi/cmaps/cmap_int.h"
+
+#include "core/fpdfapi/cpdf_modulemgr.h"
+#include "core/fpdfapi/fpdf_font/font_int.h"
+#include "core/fpdfapi/fpdf_page/cpdf_pagemodule.h"
+
+extern "C" {
+
+static int compareWord(const void* p1, const void* p2) {
+  return (*(uint16_t*)p1) - (*(uint16_t*)p2);
+}
+
+static int compareWordRange(const void* key, const void* element) {
+  if (*(uint16_t*)key < *(uint16_t*)element)
+    return -1;
+  if (*(uint16_t*)key > ((uint16_t*)element)[1])
+    return 1;
+  return 0;
+}
+
+static int compareDWordRange(const void* p1, const void* p2) {
+  uint32_t key = *(uint32_t*)p1;
+  uint16_t hiword = (uint16_t)(key >> 16);
+  uint16_t* element = (uint16_t*)p2;
+  if (hiword < element[0])
+    return -1;
+  if (hiword > element[0])
+    return 1;
+
+  uint16_t loword = (uint16_t)key;
+  if (loword < element[1])
+    return -1;
+  if (loword > element[2])
+    return 1;
+  return 0;
+}
+
+static int compareDWordSingle(const void* p1, const void* p2) {
+  uint32_t key = *(uint32_t*)p1;
+  uint32_t value = ((*(uint16_t*)p2) << 16) | ((uint16_t*)p2)[1];
+  if (key < value)
+    return -1;
+  if (key > value)
+    return 1;
+  return 0;
+}
+
+};  // extern "C"
+
+void FPDFAPI_FindEmbeddedCMap(const CFX_ByteString& bsName,
+                              int charset,
+                              int coding,
+                              const FXCMAP_CMap*& pMap) {
+  pMap = nullptr;
+  CPDF_FontGlobals* pFontGlobals =
+      CPDF_ModuleMgr::Get()->GetPageModule()->GetFontGlobals();
+  const FXCMAP_CMap* pCMaps =
+      pFontGlobals->m_EmbeddedCharsets[charset].m_pMapList;
+  for (uint32_t i = 0; i < pFontGlobals->m_EmbeddedCharsets[charset].m_Count;
+       i++) {
+    if (bsName == pCMaps[i].m_Name) {
+      pMap = &pCMaps[i];
+      break;
+    }
+  }
+}
+
+uint16_t FPDFAPI_CIDFromCharCode(const FXCMAP_CMap* pMap, uint32_t charcode) {
+  if (charcode >> 16) {
+    while (1) {
+      if (pMap->m_DWordMapType == FXCMAP_CMap::Range) {
+        uint16_t* found = static_cast<uint16_t*>(
+            FXSYS_bsearch(&charcode, pMap->m_pDWordMap, pMap->m_DWordCount, 8,
+                          compareDWordRange));
+        if (found)
+          return found[3] + (uint16_t)charcode - found[1];
+
+      } else if (pMap->m_DWordMapType == FXCMAP_CMap::Single) {
+        uint16_t* found = static_cast<uint16_t*>(
+            FXSYS_bsearch(&charcode, pMap->m_pDWordMap, pMap->m_DWordCount, 6,
+                          compareDWordSingle));
+        if (found)
+          return found[2];
+      }
+      if (pMap->m_UseOffset == 0)
+        return 0;
+
+      pMap = pMap + pMap->m_UseOffset;
+    }
+    return 0;
+  }
+
+  uint16_t code = (uint16_t)charcode;
+  while (1) {
+    if (!pMap->m_pWordMap)
+      return 0;
+    if (pMap->m_WordMapType == FXCMAP_CMap::Single) {
+      uint16_t* found = static_cast<uint16_t*>(FXSYS_bsearch(
+          &code, pMap->m_pWordMap, pMap->m_WordCount, 4, compareWord));
+      if (found)
+        return found[1];
+
+    } else if (pMap->m_WordMapType == FXCMAP_CMap::Range) {
+      uint16_t* found = static_cast<uint16_t*>(FXSYS_bsearch(
+          &code, pMap->m_pWordMap, pMap->m_WordCount, 6, compareWordRange));
+      if (found)
+        return found[2] + code - found[0];
+    }
+    if (pMap->m_UseOffset == 0)
+      return 0;
+
+    pMap = pMap + pMap->m_UseOffset;
+  }
+  return 0;
+}
+
+uint32_t FPDFAPI_CharCodeFromCID(const FXCMAP_CMap* pMap, uint16_t cid) {
+  // TODO(dsinclair): This should be checking both pMap->m_WordMap and
+  // pMap->m_DWordMap. There was a second while() but it was never reached as
+  // the first always returns. Investigate and determine how this should
+  // really be working. (https://codereview.chromium.org/2235743003 removed the
+  // second while loop.)
+  while (1) {
+    if (pMap->m_WordMapType == FXCMAP_CMap::Single) {
+      const uint16_t* pCur = pMap->m_pWordMap;
+      const uint16_t* pEnd = pMap->m_pWordMap + pMap->m_WordCount * 2;
+      while (pCur < pEnd) {
+        if (pCur[1] == cid)
+          return pCur[0];
+
+        pCur += 2;
+      }
+    } else if (pMap->m_WordMapType == FXCMAP_CMap::Range) {
+      const uint16_t* pCur = pMap->m_pWordMap;
+      const uint16_t* pEnd = pMap->m_pWordMap + pMap->m_WordCount * 3;
+      while (pCur < pEnd) {
+        if (cid >= pCur[2] && cid <= pCur[2] + pCur[1] - pCur[0])
+          return pCur[0] + cid - pCur[2];
+
+        pCur += 3;
+      }
+    }
+    if (pMap->m_UseOffset == 0)
+      return 0;
+
+    pMap = pMap + pMap->m_UseOffset;
+  }
+}