Add a createUniqueFile function and switch llvm's users of unique_file.

This function is complementary to createTemporaryFile. It handles the case were
the unique file is *not* temporary: we will rename it in the end. Since we
will rename it, the file has to be in the same filesystem as the final
destination and we don't prepend the system temporary directory.

This has a small semantic difference from unique_file: the default mode is 0666.
This matches the behavior of most unix tools. For example, with this change
lld now produces files with the same permissions as ld. I will add a test
of this change when I port clang over to createUniqueFile (next commit).

llvm-svn: 185726

Author: espindola

llvm/include/llvm/Support/FileSystem.h

@@ -575,6 +575,35 @@ error_code unique_file(const Twine &model, int &result_fd,
 error_code unique_file(const Twine &Model, SmallVectorImpl<char> &ResultPath,
                        bool MakeAbsolute = true);
 
+/// @brief Create a uniquely named file.
+///
+/// Generates a unique path suitable for a temporary file and then opens it as a
+/// file. The name is based on \a model with '%' replaced by a random char in
+/// [0-9a-f]. If \a model is not an absolute path, a suitable temporary
+/// directory will be prepended.
+///
+/// Example: clang-%%-%%-%%-%%-%%.s => clang-a0-b1-c2-d3-e4.s
+///
+/// This is an atomic operation. Either the file is created and opened, or the
+/// file system is left untouched.
+///
+/// The intendend use is for files that are to be kept, possibly after
+/// renaming them. For example, when running 'clang -c foo.o', the file can
+/// be first created as foo-abc123.o and then renamed.
+///
+/// @param Model Name to base unique path off of.
+/// @param ResultFD Set to the opened file's file descriptor.
+/// @param ResultPath Set to the opened file's absolute path.
+/// @returns errc::success if Result{FD,Path} have been successfully set,
+///          otherwise a platform specific error_code.
+error_code createUniqueFile(const Twine &Model, int &ResultFD,
+                            SmallVectorImpl<char> &ResultPath,
+                            unsigned Mode = all_read | all_write);
+
+/// @brief Simpler version for clients that don't want an open file.
+error_code createUniqueFile(const Twine &Model,
+                            SmallVectorImpl<char> &ResultPath);
+
 /// @brief Create a file in the system temporary directory.
 ///
 /// The filename is of the form prefix-random_chars.suffix. Since the directory

llvm/lib/Support/FileOutputBuffer.cpp

@@ -65,8 +65,8 @@ error_code FileOutputBuffer::create(StringRef FilePath,
   // Create new file in same directory but with random name.
   SmallString<128> TempFilePath;
   int FD;
-  EC = sys::fs::unique_file(Twine(FilePath) + ".tmp%%%%%%%",
-                            FD, TempFilePath, false, 0644);
+  EC = sys::fs::createUniqueFile(Twine(FilePath) + ".tmp%%%%%%%",
+                                 FD, TempFilePath);
   if (EC)
     return EC;
 

llvm/lib/Support/LockFileManager.cpp

@@ -78,10 +78,9 @@ LockFileManager::LockFileManager(StringRef FileName)
   UniqueLockFileName += "-%%%%%%%%";
   int UniqueLockFileID;
   if (error_code EC
-        = sys::fs::unique_file(UniqueLockFileName.str(),
-                                     UniqueLockFileID,
-                                     UniqueLockFileName,
-                                     /*makeAbsolute=*/false)) {
+        = sys::fs::createUniqueFile(UniqueLockFileName.str(),
+                                    UniqueLockFileID,
+                                    UniqueLockFileName)) {
     Error = EC;
     return;
   }

llvm/lib/Support/Path.cpp

@@ -654,6 +654,17 @@ error_code unique_file(const Twine &Model, SmallVectorImpl<char> &ResultPath,
   return createUniqueEntity(Model, Dummy, ResultPath, MakeAbsolute, 0, FS_Name);
 }
 
+error_code createUniqueFile(const Twine &Model, int &ResultFd,
+                            SmallVectorImpl<char> &ResultPath, unsigned Mode) {
+  return createUniqueEntity(Model, ResultFd, ResultPath, false, Mode, FS_File);
+}
+
+error_code createUniqueFile(const Twine &Model,
+                            SmallVectorImpl<char> &ResultPath) {
+  int Dummy;
+  return createUniqueEntity(Model, Dummy, ResultPath, false, 0, FS_Name);
+}
+
 static error_code createTemporaryFile(const Twine &Model, int &ResultFD,
                                       llvm::SmallVectorImpl<char> &ResultPath,
                                       FSEntity Type) {

llvm/tools/bugpoint/ExecutionDriver.cpp

@@ -267,7 +267,7 @@ void BugDriver::compileProgram(Module *M, std::string *Error) const {
   // Emit the program to a bitcode file...
   SmallString<128> BitcodeFile;
   int BitcodeFD;
-  error_code EC = sys::fs::unique_file(
+  error_code EC = sys::fs::createUniqueFile(
       OutputPrefix + "-test-program-%%%%%%%.bc", BitcodeFD, BitcodeFile);
   if (EC) {
     errs() << ToolName << ": Error making unique filename: " << EC.message()
@@ -306,7 +306,7 @@ std::string BugDriver::executeProgram(const Module *Program,
     // Emit the program to a bitcode file...
     SmallString<128> UniqueFilename;
     int UniqueFD;
-    error_code EC = sys::fs::unique_file(
+    error_code EC = sys::fs::createUniqueFile(
         OutputPrefix + "-test-program-%%%%%%%.bc", UniqueFD, UniqueFilename);
     if (EC) {
       errs() << ToolName << ": Error making unique filename: "
@@ -332,7 +332,7 @@ std::string BugDriver::executeProgram(const Module *Program,
 
   // Check to see if this is a valid output filename...
   SmallString<128> UniqueFile;
-  error_code EC = sys::fs::unique_file(OutputFile, UniqueFile);
+  error_code EC = sys::fs::createUniqueFile(OutputFile, UniqueFile);
   if (EC) {
     errs() << ToolName << ": Error making unique filename: "
            << EC.message() << "\n";

llvm/tools/bugpoint/ExtractFunction.cpp

@@ -365,8 +365,8 @@ Module *BugDriver::ExtractMappedBlocksFromModule(const
                                                  Module *M) {
   SmallString<128> Filename;
   int FD;
-  error_code EC = sys::fs::unique_file(OutputPrefix + "-extractblocks%%%%%%%",
-                                       FD, Filename);
+  error_code EC = sys::fs::createUniqueFile(
+      OutputPrefix + "-extractblocks%%%%%%%", FD, Filename);
   if (EC) {
     outs() << "*** Basic Block extraction failed!\n";
     errs() << "Error creating temporary file: " << EC.message() << "\n";

llvm/tools/bugpoint/OptimizerDriver.cpp

@@ -124,8 +124,8 @@ bool BugDriver::runPasses(Module *Program,
   // setup the output file name
   outs().flush();
   SmallString<128> UniqueFilename;
-  error_code EC =
-      sys::fs::unique_file(OutputPrefix + "-output-%%%%%%%.bc", UniqueFilename);
+  error_code EC = sys::fs::createUniqueFile(
+      OutputPrefix + "-output-%%%%%%%.bc", UniqueFilename);
   if (EC) {
     errs() << getToolName() << ": Error making unique filename: "
            << EC.message() << "\n";
@@ -136,8 +136,8 @@ bool BugDriver::runPasses(Module *Program,
   // set up the input file name
   SmallString<128> InputFilename;
   int InputFD;
-  EC = sys::fs::unique_file(OutputPrefix + "-input-%%%%%%%.bc", InputFD,
-                            InputFilename);
+  EC = sys::fs::createUniqueFile(OutputPrefix + "-input-%%%%%%%.bc", InputFD,
+                                 InputFilename);
   if (EC) {
     errs() << getToolName() << ": Error making unique filename: "
            << EC.message() << "\n";

llvm/tools/bugpoint/ToolRunner.cpp

@@ -478,7 +478,7 @@ GCC::FileType LLC::OutputCode(const std::string &Bitcode,
 
   SmallString<128> UniqueFile;
   error_code EC =
-      sys::fs::unique_file(Bitcode + "-%%%%%%%" + Suffix, UniqueFile);
+      sys::fs::createUniqueFile(Bitcode + "-%%%%%%%" + Suffix, UniqueFile);
   if (EC) {
     errs() << "Error making unique filename: " << EC.message() << "\n";
     exit(1);
@@ -715,7 +715,7 @@ int GCC::ExecuteProgram(const std::string &ProgramFile,
 
   SmallString<128> OutputBinary;
   error_code EC =
-      sys::fs::unique_file(ProgramFile+ "-%%%%%%%.gcc.exe", OutputBinary);
+      sys::fs::createUniqueFile(ProgramFile + "-%%%%%%%.gcc.exe", OutputBinary);
   if (EC) {
     errs() << "Error making unique filename: " << EC.message() << "\n";
     exit(1);
@@ -824,8 +824,8 @@ int GCC::MakeSharedObject(const std::string &InputFile, FileType fileType,
                           const std::vector<std::string> &ArgsForGCC,
                           std::string &Error) {
   SmallString<128> UniqueFilename;
-  error_code EC = sys::fs::unique_file(InputFile + "-%%%%%%%" + LTDL_SHLIB_EXT,
-                                       UniqueFilename);
+  error_code EC = sys::fs::createUniqueFile(
+      InputFile + "-%%%%%%%" + LTDL_SHLIB_EXT, UniqueFilename);
   if (EC) {
     errs() << "Error making unique filename: " << EC.message() << "\n";
     exit(1);

llvm/tools/llvm-ar/ArchiveWriter.cpp

@@ -260,8 +260,8 @@ bool Archive::writeToDisk(bool TruncateNames, std::string *ErrMsg) {
   // Create a temporary file to store the archive in
   int TmpArchiveFD;
   SmallString<128> TmpArchive;
-  error_code EC = sys::fs::unique_file("temp-archive-%%%%%%%.a", TmpArchiveFD,
-                                       TmpArchive, true, sys::fs::all_read | sys::fs::all_write);
+  error_code EC = sys::fs::createUniqueFile("temp-archive-%%%%%%%.a",
+                                            TmpArchiveFD, TmpArchive);
   if (EC)
     return true;