Shamelessly copy Josiah

source/lib/json/tests/thirdparty/Fuzzer/FuzzerIO.cpp

@@ -0,0 +1,117 @@
+//===- FuzzerIO.cpp - IO utils. -------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+// IO functions.
+//===----------------------------------------------------------------------===//
+
+#include "FuzzerIO.h"
+#include "FuzzerDefs.h"
+#include "FuzzerExtFunctions.h"
+#include <algorithm>
+#include <cstdarg>
+#include <fstream>
+#include <iterator>
+#include <sys/stat.h>
+#include <sys/types.h>
+
+namespace fuzzer {
+
+static FILE *OutputFile = stderr;
+
+long GetEpoch(const std::string &Path) {
+  struct stat St;
+  if (stat(Path.c_str(), &St))
+    return 0;  // Can't stat, be conservative.
+  return St.st_mtime;
+}
+
+Unit FileToVector(const std::string &Path, size_t MaxSize, bool ExitOnError) {
+  std::ifstream T(Path);
+  if (ExitOnError && !T) {
+    Printf("No such directory: %s; exiting\n", Path.c_str());
+    exit(1);
+  }
+
+  T.seekg(0, T.end);
+  size_t FileLen = T.tellg();
+  if (MaxSize)
+    FileLen = std::min(FileLen, MaxSize);
+
+  T.seekg(0, T.beg);
+  Unit Res(FileLen);
+  T.read(reinterpret_cast<char *>(Res.data()), FileLen);
+  return Res;
+}
+
+std::string FileToString(const std::string &Path) {
+  std::ifstream T(Path);
+  return std::string((std::istreambuf_iterator<char>(T)),
+                     std::istreambuf_iterator<char>());
+}
+
+void CopyFileToErr(const std::string &Path) {
+  Printf("%s", FileToString(Path).c_str());
+}
+
+void WriteToFile(const Unit &U, const std::string &Path) {
+  // Use raw C interface because this function may be called from a sig handler.
+  FILE *Out = fopen(Path.c_str(), "w");
+  if (!Out) return;
+  fwrite(U.data(), sizeof(U[0]), U.size(), Out);
+  fclose(Out);
+}
+
+void ReadDirToVectorOfUnits(const char *Path, std::vector<Unit> *V,
+                            long *Epoch, size_t MaxSize, bool ExitOnError) {
+  long E = Epoch ? *Epoch : 0;
+  std::vector<std::string> Files;
+  ListFilesInDirRecursive(Path, Epoch, &Files, /*TopDir*/true);
+  size_t NumLoaded = 0;
+  for (size_t i = 0; i < Files.size(); i++) {
+    auto &X = Files[i];
+    if (Epoch && GetEpoch(X) < E) continue;
+    NumLoaded++;
+    if ((NumLoaded & (NumLoaded - 1)) == 0 && NumLoaded >= 1024)
+      Printf("Loaded %zd/%zd files from %s\n", NumLoaded, Files.size(), Path);
+    auto S = FileToVector(X, MaxSize, ExitOnError);
+    if (!S.empty())
+      V->push_back(S);
+  }
+}
+
+std::string DirPlusFile(const std::string &DirPath,
+                        const std::string &FileName) {
+  return DirPath + GetSeparator() + FileName;
+}
+
+void DupAndCloseStderr() {
+  int OutputFd = DuplicateFile(2);
+  if (OutputFd > 0) {
+    FILE *NewOutputFile = OpenFile(OutputFd, "w");
+    if (NewOutputFile) {
+      OutputFile = NewOutputFile;
+      if (EF->__sanitizer_set_report_fd)
+        EF->__sanitizer_set_report_fd(reinterpret_cast<void *>(OutputFd));
+      CloseFile(2);
+    }
+  }
+}
+
+void CloseStdout() {
+  CloseFile(1);
+}
+
+void Printf(const char *Fmt, ...) {
+  va_list ap;
+  va_start(ap, Fmt);
+  vfprintf(OutputFile, Fmt, ap);
+  va_end(ap);
+  fflush(OutputFile);
+}
+
+}  // namespace fuzzer