FileManager: Remove ShouldCloseOpenFile argument from getBufferForFile, NFC

[dexonsmith]

Summary

Remove this dead code. We always close the file.

[Bigcheese]

lgtm

[dexonsmith]

r370488

clang/include/clang/Basic/FileManager.h

public:
   ///
   /// The file itself is not accessed.
   const FileEntry *getVirtualFile(StringRef Filename, off_t Size,
                                   time_t ModificationTime);
 
   /// Open the specified file as a MemoryBuffer, returning a new
   /// MemoryBuffer if successful, otherwise returning null.
   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
-  getBufferForFile(const FileEntry *Entry, bool isVolatile = false,
-                   bool ShouldCloseOpenFile = true);
+  getBufferForFile(const FileEntry *Entry, bool isVolatile = false);
   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
   getBufferForFile(StringRef Filename, bool isVolatile = false) {
     return getBufferForFileImpl(Filename, /*FileSize=*/-1, isVolatile);
   }
 
 private:
   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
   getBufferForFileImpl(StringRef Filename, int64_t FileSize, bool isVolatile);

clang/lib/Basic/FileManager.cpp

void FileManager::fillRealPathName(FileEntry *UFE, llvm::StringRef FileName) {
   // FIXME: the semantic of RealPathName is unclear, and the name might be
   // misleading. We need to clean up the interface here.
   makeAbsolutePath(AbsPath);
   llvm::sys::path::remove_dots(AbsPath, /*remove_dot_dot=*/true);
   UFE->RealPathName = AbsPath.str();
 }
 
 llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>
-FileManager::getBufferForFile(const FileEntry *Entry, bool isVolatile,
-                              bool ShouldCloseOpenFile) {
+FileManager::getBufferForFile(const FileEntry *Entry, bool isVolatile) {
   uint64_t FileSize = Entry->getSize();
   // If there's a high enough chance that the file have changed since we
   // got its size, force a stat before opening it.
   if (isVolatile)
     FileSize = -1;
 
   StringRef Filename = Entry->getName();
   // If the file is already open, use the open file descriptor.
   if (Entry->File) {
     auto Result =
         Entry->File->getBuffer(Filename, FileSize,
                                /*RequiresNullTerminator=*/true, isVolatile);
-    // FIXME: we need a set of APIs that can make guarantees about whether a
-    // FileEntry is open or not.
-    if (ShouldCloseOpenFile)
-      Entry->closeFile();
     return Result;
   }
 
   // Otherwise, open the file.
   return getBufferForFileImpl(Filename, FileSize, isVolatile);
 }
 
 llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>>

clang/lib/Serialization/ModuleManager.cpp

if (std::unique_ptr<llvm::MemoryBuffer> Buffer = lookupBuffer(FileName)) {
     return OutOfDate;
   } else {
     // Open the AST file.
     llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> Buf((std::error_code()));
     if (FileName == "-") {
       Buf = llvm::MemoryBuffer::getSTDIN();
     } else {
       // Get a buffer of the file and close the file descriptor when done.
-      Buf = FileMgr.getBufferForFile(NewModule->File,
-                                     /*isVolatile=*/false,
-                                     /*ShouldClose=*/true);
+      Buf = FileMgr.getBufferForFile(NewModule->File, /*isVolatile=*/false);
     }
 
     if (!Buf) {
       ErrorStr = Buf.getError().message();
       return Missing;
     }
 
     NewModule->Buffer = &getModuleCache().addPCM(FileName, std::move(*Buf));