[LibFuzzer] Split up some functions among different headers.

In an effort to get libfuzzer working on Windows, we need to make
a distinction between what functions require platform specific
code (e.g. different code on Windows vs Linux) and what code
doesn't.  IO functions, for example, tend to be platform
specific.

This patch separates out some of the functions which will need
to have platform specific implementations into different headers,
so that we can then provide different implementations for each
platform.

Aside from that, this patch contains no functional change.  It
is purely a re-organization.

Patch by Marcos Pividori
Differential Revision: https://reviews.llvm.org/D27230

llvm-svn: 288264
diff --git a/llvm/lib/Fuzzer/FuzzerDefs.h b/llvm/lib/Fuzzer/FuzzerDefs.h
index 13aa212..89d675a 100644
--- a/llvm/lib/Fuzzer/FuzzerDefs.h
+++ b/llvm/lib/Fuzzer/FuzzerDefs.h
@@ -63,65 +63,9 @@
 typedef std::vector<uint8_t> Unit;
 typedef std::vector<Unit> UnitVector;
 typedef int (*UserCallback)(const uint8_t *Data, size_t Size);
+
 int FuzzerDriver(int *argc, char ***argv, UserCallback Callback);
 
-bool IsFile(const std::string &Path);
-long GetEpoch(const std::string &Path);
-std::string FileToString(const std::string &Path);
-Unit FileToVector(const std::string &Path, size_t MaxSize = 0,
-                  bool ExitOnError = true);
-void ReadDirToVectorOfUnits(const char *Path, std::vector<Unit> *V,
-                            long *Epoch, size_t MaxSize, bool ExitOnError);
-void WriteToFile(const Unit &U, const std::string &Path);
-void CopyFileToErr(const std::string &Path);
-void DeleteFile(const std::string &Path);
-// Returns "Dir/FileName" or equivalent for the current OS.
-std::string DirPlusFile(const std::string &DirPath,
-                        const std::string &FileName);
-
-void DupAndCloseStderr();
-void CloseStdout();
-void Printf(const char *Fmt, ...);
-void PrintHexArray(const Unit &U, const char *PrintAfter = "");
-void PrintHexArray(const uint8_t *Data, size_t Size,
-                   const char *PrintAfter = "");
-void PrintASCII(const uint8_t *Data, size_t Size, const char *PrintAfter = "");
-void PrintASCII(const Unit &U, const char *PrintAfter = "");
-
-void PrintPC(const char *SymbolizedFMT, const char *FallbackFMT, uintptr_t PC);
-std::string DescribePC(const char *SymbolizedFMT, uintptr_t PC);
-std::string Hash(const Unit &U);
-void SetTimer(int Seconds);
-void SetSigSegvHandler();
-void SetSigBusHandler();
-void SetSigAbrtHandler();
-void SetSigIllHandler();
-void SetSigFpeHandler();
-void SetSigIntHandler();
-void SetSigTermHandler();
-std::string Base64(const Unit &U);
-int ExecuteCommand(const std::string &Command);
-bool ExecuteCommandAndReadOutput(const std::string &Command, std::string *Out);
-
-size_t GetPeakRSSMb();
-
-// Private copy of SHA1 implementation.
-static const int kSHA1NumBytes = 20;
-// Computes SHA1 hash of 'Len' bytes in 'Data', writes kSHA1NumBytes to 'Out'.
-void ComputeSHA1(const uint8_t *Data, size_t Len, uint8_t *Out);
-std::string Sha1ToString(const uint8_t Sha1[kSHA1NumBytes]);
-
-// Changes U to contain only ASCII (isprint+isspace) characters.
-// Returns true iff U has been changed.
-bool ToASCII(uint8_t *Data, size_t Size);
-bool IsASCII(const Unit &U);
-bool IsASCII(const uint8_t *Data, size_t Size);
-
-int NumberOfCpuCores();
-int GetPid();
-void SleepSeconds(int Seconds);
-
-
 struct ScopedDoingMyOwnMemmem {
   ScopedDoingMyOwnMemmem();
   ~ScopedDoingMyOwnMemmem();