[LibFuzzer] Add Windows implementations of some IO functions.

This patch moves some posix specific file i/o code into a new
file, FuzzerIOPosix.cpp, and provides implementations for these
functions on Windows in FuzzerIOWindows.cpp.  This is another
incremental step towards getting libfuzzer working on Windows,
although it still should not be expected to be fully working.

Patch by Marcos Pividori
Differential Revision: https://reviews.llvm.org/D27233

llvm-svn: 288275

llvm/lib/Fuzzer/CMakeLists.txt

@@ -10,15 +10,17 @@ if( LLVM_USE_SANITIZE_COVERAGE )
   endif()
   add_library(LLVMFuzzerNoMainObjects OBJECT
     FuzzerCrossOver.cpp
-    FuzzerTraceState.cpp
     FuzzerDriver.cpp
     FuzzerExtFunctionsDlsym.cpp
     FuzzerExtFunctionsWeak.cpp
     FuzzerIO.cpp
+    FuzzerIOPosix.cpp
+    FuzzerIOWindows.cpp
     FuzzerLoop.cpp
     FuzzerMutate.cpp
     FuzzerSHA1.cpp
     FuzzerTracePC.cpp
+    FuzzerTraceState.cpp
     FuzzerUtil.cpp
     FuzzerUtilDarwin.cpp
     FuzzerUtilLinux.cpp

llvm/lib/Fuzzer/FuzzerIO.cpp

@@ -11,26 +11,17 @@
 #include "FuzzerIO.h"
 #include "FuzzerDefs.h"
 #include "FuzzerExtFunctions.h"
-#include <iterator>
+#include <algorithm>
+#include <cstdarg>
 #include <fstream>
-#include <dirent.h>
+#include <iterator>
 #include <sys/types.h>
 #include <sys/stat.h>
-#include <unistd.h>
-#include <cstdarg>
-#include <cstdio>
 
 namespace fuzzer {
 
 static FILE *OutputFile = stderr;
 
-bool IsFile(const std::string &Path) {
-  struct stat St;
-  if (stat(Path.c_str(), &St))
-    return false;
-  return S_ISREG(St.st_mode);
-}
-
 long GetEpoch(const std::string &Path) {
   struct stat St;
   if (stat(Path.c_str(), &St))
@@ -38,29 +29,6 @@ long GetEpoch(const std::string &Path) {
   return St.st_mtime;
 }
 
-static void ListFilesInDirRecursive(const std::string &Dir, long *Epoch,
-                                    std::vector<std::string> *V, bool TopDir) {
-  auto E = GetEpoch(Dir);
-  if (Epoch)
-    if (E && *Epoch >= E) return;
-
-  DIR *D = opendir(Dir.c_str());
-  if (!D) {
-    Printf("No such directory: %s; exiting\n", Dir.c_str());
-    exit(1);
-  }
-  while (auto E = readdir(D)) {
-    std::string Path = DirPlusFile(Dir, E->d_name);
-    if (E->d_type == DT_REG || E->d_type == DT_LNK)
-      V->push_back(Path);
-    else if (E->d_type == DT_DIR && *E->d_name != '.')
-      ListFilesInDirRecursive(Path, Epoch, V, false);
-  }
-  closedir(D);
-  if (Epoch && TopDir)
-    *Epoch = E;
-}
-
 Unit FileToVector(const std::string &Path, size_t MaxSize, bool ExitOnError) {
   std::ifstream T(Path);
   if (ExitOnError && !T) {
@@ -79,10 +47,6 @@ Unit FileToVector(const std::string &Path, size_t MaxSize, bool ExitOnError) {
   return Res;
 }
 
-void DeleteFile(const std::string &Path) {
-  unlink(Path.c_str());
-}
-
 std::string FileToString(const std::string &Path) {
   std::ifstream T(Path);
   return std::string((std::istreambuf_iterator<char>(T)),
@@ -121,23 +85,25 @@ void ReadDirToVectorOfUnits(const char *Path, std::vector<Unit> *V,
 
 std::string DirPlusFile(const std::string &DirPath,
                         const std::string &FileName) {
-  return DirPath + "/" + FileName;
+  return DirPath + GetSeparator() + FileName;
 }
 
 void DupAndCloseStderr() {
-  int OutputFd = dup(2);
+  int OutputFd = DuplicateFile(2);
   if (OutputFd > 0) {
-    FILE *NewOutputFile = fdopen(OutputFd, "w");
+    FILE *NewOutputFile = OpenFile(OutputFd, "w");
     if (NewOutputFile) {
       OutputFile = NewOutputFile;
       if (EF->__sanitizer_set_report_fd)
         EF->__sanitizer_set_report_fd(reinterpret_cast<void *>(OutputFd));
-      close(2);
+      CloseFile(2);
     }
   }
 }
 
-void CloseStdout() { close(1); }
+void CloseStdout() {
+  CloseFile(1);
+}
 
 void Printf(const char *Fmt, ...) {
   va_list ap;

llvm/lib/Fuzzer/FuzzerIO.h

@@ -15,15 +15,11 @@
 
 namespace fuzzer {
 
-bool IsFile(const std::string &Path);
-
 long GetEpoch(const std::string &Path);
 
 Unit FileToVector(const std::string &Path, size_t MaxSize = 0,
                   bool ExitOnError = true);
 
-void DeleteFile(const std::string &Path);
-
 std::string FileToString(const std::string &Path);
 
 void CopyFileToErr(const std::string &Path);
@@ -43,5 +39,21 @@ void CloseStdout();
 
 void Printf(const char *Fmt, ...);
 
+// Platform specific functions:
+bool IsFile(const std::string &Path);
+
+void ListFilesInDirRecursive(const std::string &Dir, long *Epoch,
+                             std::vector<std::string> *V, bool TopDir);
+
+char GetSeparator();
+
+FILE* OpenFile(int Fd, const char *Mode);
+
+int CloseFile(int Fd);
+
+int DuplicateFile(int Fd);
+
+void DeleteFile(const std::string &Path);
+
 }  // namespace fuzzer
 #endif  // LLVM_FUZZER_IO_H

llvm/lib/Fuzzer/FuzzerIOPosix.cpp

@@ -0,0 +1,78 @@
+//===- FuzzerIOPosix.cpp - IO utils for Posix. ----------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+// IO functions implementation using Posix API.
+//===----------------------------------------------------------------------===//
+
+#include "FuzzerDefs.h"
+#if LIBFUZZER_POSIX
+#include "FuzzerExtFunctions.h"
+#include "FuzzerIO.h"
+#include <cstdarg>
+#include <cstdio>
+#include <dirent.h>
+#include <fstream>
+#include <iterator>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+namespace fuzzer {
+
+bool IsFile(const std::string &Path) {
+  struct stat St;
+  if (stat(Path.c_str(), &St))
+    return false;
+  return S_ISREG(St.st_mode);
+}
+
+void ListFilesInDirRecursive(const std::string &Dir, long *Epoch,
+                             std::vector<std::string> *V, bool TopDir) {
+  auto E = GetEpoch(Dir);
+  if (Epoch)
+    if (E && *Epoch >= E) return;
+
+  DIR *D = opendir(Dir.c_str());
+  if (!D) {
+    Printf("No such directory: %s; exiting\n", Dir.c_str());
+    exit(1);
+  }
+  while (auto E = readdir(D)) {
+    std::string Path = DirPlusFile(Dir, E->d_name);
+    if (E->d_type == DT_REG || E->d_type == DT_LNK)
+      V->push_back(Path);
+    else if (E->d_type == DT_DIR && *E->d_name != '.')
+      ListFilesInDirRecursive(Path, Epoch, V, false);
+  }
+  closedir(D);
+  if (Epoch && TopDir)
+    *Epoch = E;
+}
+
+char GetSeparator() {
+  return '/';
+}
+
+FILE* OpenFile(int Fd, const char* Mode) {
+  return fdopen(Fd, Mode);
+}
+
+int CloseFile(int fd) {
+  return close(fd);
+}
+
+int DuplicateFile(int Fd) {
+  return dup(Fd);
+}
+
+void DeleteFile(const std::string &Path) {
+  unlink(Path.c_str());
+}
+
+}  // namespace fuzzer
+#endif // LIBFUZZER_POSIX

llvm/lib/Fuzzer/FuzzerIOWindows.cpp

@@ -0,0 +1,143 @@
+//===- FuzzerIOWindows.cpp - IO utils for Windows. ------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+// IO functions implementation for Windows.
+//===----------------------------------------------------------------------===//
+
+#include "FuzzerDefs.h"
+#if LIBFUZZER_WINDOWS
+#include "FuzzerExtFunctions.h"
+#include "FuzzerIO.h"
+#include <cstdarg>
+#include <cstdio>
+#include <fstream>
+#include <io.h>
+#include <iterator>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <windows.h>
+
+namespace fuzzer {
+
+static bool IsFile(const std::string &Path, const DWORD &FileAttributes) {
+
+  if (FileAttributes & FILE_ATTRIBUTE_NORMAL)
+    return true;
+
+  if (FileAttributes & FILE_ATTRIBUTE_DIRECTORY)
+    return false;
+
+  HANDLE FileHandle(
+      CreateFileA(Path.c_str(), 0, FILE_SHARE_READ, NULL, OPEN_EXISTING,
+                  FILE_FLAG_BACKUP_SEMANTICS, 0));
+
+  if (FileHandle == INVALID_HANDLE_VALUE) {
+    Printf("CreateFileA() failed for \"%s\" (Error code: %lu).\n", Path.c_str(),
+        GetLastError());
+    return false;
+  }
+
+  DWORD FileType = GetFileType(FileHandle);
+
+  if (FileType == FILE_TYPE_UNKNOWN) {
+    Printf("GetFileType() failed for \"%s\" (Error code: %lu).\n", Path.c_str(),
+        GetLastError());
+    CloseHandle(FileHandle);
+    return false;
+  }
+
+  if (FileType != FILE_TYPE_DISK) {
+    CloseHandle(FileHandle);
+    return false;
+  }
+
+  CloseHandle(FileHandle);
+  return true;
+}
+
+bool IsFile(const std::string &Path) {
+  DWORD Att = GetFileAttributesA(Path.c_str());
+
+  if (Att == INVALID_FILE_ATTRIBUTES) {
+    Printf("GetFileAttributesA() failed for \"%s\" (Error code: %lu).\n",
+        Path.c_str(), GetLastError());
+    return false;
+  }
+
+  return IsFile(Path, Att);
+}
+
+void ListFilesInDirRecursive(const std::string &Dir, long *Epoch,
+                             std::vector<std::string> *V, bool TopDir) {
+  auto E = GetEpoch(Dir);
+  if (Epoch)
+    if (E && *Epoch >= E) return;
+
+  std::string Path(Dir);
+  assert(!Path.empty());
+  if (Path.back() != '\\')
+      Path.push_back('\\');
+  Path.push_back('*');
+
+  // Get the first directory entry.
+  WIN32_FIND_DATAA FindInfo;
+  HANDLE FindHandle(FindFirstFileA(Path.c_str(), &FindInfo));
+  if (FindHandle == INVALID_HANDLE_VALUE)
+  {
+    Printf("No file found in: %s.\n", Dir.c_str());
+    return;
+  }
+
+  do {
+    std::string FileName = DirPlusFile(Dir, FindInfo.cFileName);
+
+    if (FindInfo.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) {
+      size_t FilenameLen = strlen(FindInfo.cFileName);
+      if ((FilenameLen == 1 && FindInfo.cFileName[0] == '.') ||
+          (FilenameLen == 2 && FindInfo.cFileName[0] == '.' &&
+                               FindInfo.cFileName[1] == '.'))
+        continue;
+
+      ListFilesInDirRecursive(FileName, Epoch, V, false);
+    }
+    else if (IsFile(FileName, FindInfo.dwFileAttributes))
+      V->push_back(FileName);
+  } while (FindNextFileA(FindHandle, &FindInfo));
+
+  DWORD LastError = GetLastError();
+  if (LastError != ERROR_NO_MORE_FILES)
+    Printf("FindNextFileA failed (Error code: %lu).\n", LastError);
+
+  FindClose(FindHandle);
+
+  if (Epoch && TopDir)
+    *Epoch = E;
+}
+
+char GetSeparator() {
+  return '\\';
+}
+
+FILE* OpenFile(int Fd, const char* Mode) {
+  return _fdopen(Fd, Mode);
+}
+
+int CloseFile(int Fd) {
+  return _close(Fd);
+}
+
+int DuplicateFile(int Fd) {
+  return _dup(Fd);
+}
+
+void DeleteFile(const std::string &Path) {
+  _unlink(Path.c_str());
+}
+
+}  // namespace fuzzer
+#endif // LIBFUZZER_WINDOWS