add libfuzzer custom mutator, minor enhancements and fixes

custom_mutators/libfuzzer/FuzzerIO.h

@@ -0,0 +1,112 @@
+//===- FuzzerIO.h - Internal header for IO utils ----------------*- C++ -* ===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+// IO interface.
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZER_IO_H
+#define LLVM_FUZZER_IO_H
+
+#include "FuzzerDefs.h"
+
+namespace fuzzer {
+
+long GetEpoch(const std::string &Path);
+
+Unit FileToVector(const std::string &Path, size_t MaxSize = 0,
+                  bool ExitOnError = true);
+
+std::string FileToString(const std::string &Path);
+
+void CopyFileToErr(const std::string &Path);
+
+void WriteToFile(const uint8_t *Data, size_t Size, const std::string &Path);
+// Write Data.c_str() to the file without terminating null character.
+void WriteToFile(const std::string &Data, const std::string &Path);
+void WriteToFile(const Unit &U, const std::string &Path);
+
+void AppendToFile(const uint8_t *Data, size_t Size, const std::string &Path);
+void AppendToFile(const std::string &Data, const std::string &Path);
+
+void ReadDirToVectorOfUnits(const char *Path, Vector<Unit> *V,
+                            long *Epoch, size_t MaxSize, bool ExitOnError);
+
+// Returns "Dir/FileName" or equivalent for the current OS.
+std::string DirPlusFile(const std::string &DirPath,
+                        const std::string &FileName);
+
+// Returns the name of the dir, similar to the 'dirname' utility.
+std::string DirName(const std::string &FileName);
+
+// Returns path to a TmpDir.
+std::string TmpDir();
+
+std::string TempPath(const char *Prefix, const char *Extension);
+
+bool IsInterestingCoverageFile(const std::string &FileName);
+
+void DupAndCloseStderr();
+
+void CloseStdout();
+
+void Printf(const char *Fmt, ...);
+void VPrintf(bool Verbose, const char *Fmt, ...);
+
+// Print using raw syscalls, useful when printing at early init stages.
+void RawPrint(const char *Str);
+
+// Platform specific functions:
+bool IsFile(const std::string &Path);
+bool IsDirectory(const std::string &Path);
+size_t FileSize(const std::string &Path);
+
+void ListFilesInDirRecursive(const std::string &Dir, long *Epoch,
+                             Vector<std::string> *V, bool TopDir);
+
+bool MkDirRecursive(const std::string &Dir);
+void RmDirRecursive(const std::string &Dir);
+
+// Iterate files and dirs inside Dir, recursively.
+// Call DirPreCallback/DirPostCallback on dirs before/after
+// calling FileCallback on files.
+void IterateDirRecursive(const std::string &Dir,
+                         void (*DirPreCallback)(const std::string &Dir),
+                         void (*DirPostCallback)(const std::string &Dir),
+                         void (*FileCallback)(const std::string &Dir));
+
+struct SizedFile {
+  std::string File;
+  size_t Size;
+  bool operator<(const SizedFile &B) const { return Size < B.Size; }
+};
+
+void GetSizedFilesFromDir(const std::string &Dir, Vector<SizedFile> *V);
+
+char GetSeparator();
+bool IsSeparator(char C);
+// Similar to the basename utility: returns the file name w/o the dir prefix.
+std::string Basename(const std::string &Path);
+
+FILE* OpenFile(int Fd, const char *Mode);
+
+int CloseFile(int Fd);
+
+int DuplicateFile(int Fd);
+
+void RemoveFile(const std::string &Path);
+void RenameFile(const std::string &OldPath, const std::string &NewPath);
+
+intptr_t GetHandleFromFd(int fd);
+
+void MkDir(const std::string &Path);
+void RmDir(const std::string &Path);
+
+const std::string &getDevNull();
+
+}  // namespace fuzzer
+
+#endif  // LLVM_FUZZER_IO_H