Revert "Revert "Revert "Cleanup some numeric code."""

core/src/fxcrt/fx_extension.cpp

 // 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 "../../include/fxcrt/fx_basic.h"
 #include "../../include/fxcrt/fx_ext.h"
 #include "extension.h"
-
 #if _FXM_PLATFORM_ == _FXM_PLATFORM_WINDOWS_
 #include <wincrypt.h>
 #else
 #include <ctime>
 #endif
 
 IFX_FileStream* FX_CreateFileStream(const FX_CHAR* filename, FX_DWORD dwModes) {
   IFXCRT_FileAccess* pFA = FXCRT_FileAccess_Create();
   if (!pFA) {
     return NULL;
@@ skipping 23 matching lines @@
   return FX_CreateFileStream(filename, FX_FILEMODE_ReadOnly);
 }
 IFX_MemoryStream* FX_CreateMemoryStream(uint8_t* pBuffer,
                                         size_t dwSize,
                                         FX_BOOL bTakeOver) {
   return new CFX_MemoryStream(pBuffer, dwSize, bTakeOver);
 }
 IFX_MemoryStream* FX_CreateMemoryStream(FX_BOOL bConsecutive) {
   return new CFX_MemoryStream(bConsecutive);
 }
-
+#ifdef __cplusplus
+extern "C" {
+#endif
 FX_FLOAT FXSYS_tan(FX_FLOAT a) {
   return (FX_FLOAT)tan(a);
 }
 FX_FLOAT FXSYS_logb(FX_FLOAT b, FX_FLOAT x) {
   return FXSYS_log(x) / FXSYS_log(b);
 }
 FX_FLOAT FXSYS_strtof(const FX_CHAR* pcsStr,
                       int32_t iLength,
                       int32_t* pUsedLen) {
   FXSYS_assert(pcsStr != NULL);
@@ skipping 116 matching lines @@
     while (pStr < pStrEnd) {
       dwHashCode = 1313 * dwHashCode + FXSYS_tolower(*pStr++);
     }
   } else {
     while (pStr < pStrEnd) {
       dwHashCode = 1313 * dwHashCode + *pStr++;
     }
   }
   return dwHashCode;
 }
-
+#ifdef __cplusplus
+}
+#endif
+#ifdef __cplusplus
+extern "C" {
+#endif
 void* FX_Random_MT_Start(FX_DWORD dwSeed) {
   FX_LPMTRANDOMCONTEXT pContext = FX_Alloc(FX_MTRANDOMCONTEXT, 1);
   pContext->mt[0] = dwSeed;
   FX_DWORD& i = pContext->mti;
   FX_DWORD* pBuf = pContext->mt;
   for (i = 1; i < MT_N; i++) {
     pBuf[i] = (1812433253UL * (pBuf[i - 1] ^ (pBuf[i - 1] >> 30)) + i);
   }
   pContext->bHaveSeed = TRUE;
   return pContext;
@@ skipping 82 matching lines @@
   return TRUE;
 }
 #endif
 void FX_Random_GenerateCrypto(FX_DWORD* pBuffer, int32_t iCount) {
 #if _FXM_PLATFORM_ == _FXM_PLATFORM_WINDOWS_
   FX_GenerateCryptoRandom(pBuffer, iCount);
 #else
   FX_Random_GenerateBase(pBuffer, iCount);
 #endif
 }
-
+#ifdef __cplusplus
+}
+#endif