[Support] Make FileOutputBuffer work on Windows.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169167 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 60 insertions, 105 deletions

diff --git a/include/llvm/Support/FileOutputBuffer.h b/include/llvm/Support/FileOutputBuffer.h
index bcd35e3c1e..cbc9c467d2 100644
--- a/include/llvm/Support/FileOutputBuffer.h
+++ b/include/llvm/Support/FileOutputBuffer.h
@@ -14,85 +14,79 @@
 #ifndef LLVM_SUPPORT_FILEOUTPUTBUFFER_H
 #define LLVM_SUPPORT_FILEOUTPUTBUFFER_H
 
+#include "llvm/ADT/OwningPtr.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/DataTypes.h"
+#include "llvm/Support/FileSystem.h"
 
 namespace llvm {
-
 class error_code;
-template<class T> class OwningPtr;
 
 /// FileOutputBuffer - This interface provides simple way to create an in-memory
-/// buffer which will be written to a file. During the lifetime of these 
+/// buffer which will be written to a file. During the lifetime of these
 /// objects, the content or existence of the specified file is undefined. That
 /// is, creating an OutputBuffer for a file may immediately remove the file.
-/// If the FileOutputBuffer is committed, the target file's content will become 
-/// the buffer content at the time of the commit.  If the FileOutputBuffer is  
+/// If the FileOutputBuffer is committed, the target file's content will become
+/// the buffer content at the time of the commit.  If the FileOutputBuffer is
 /// not committed, the file will be deleted in the FileOutputBuffer destructor.
 class FileOutputBuffer {
 public:
 
   enum  {
     F_executable = 1  /// set the 'x' bit on the resulting file
-  }; 
+  };
 
   /// Factory method to create an OutputBuffer object which manages a read/write
   /// buffer of the specified size. When committed, the buffer will be written
-  /// to the file at the specified path.  
-  static error_code create(StringRef FilePath, size_t Size, 
-                           OwningPtr<FileOutputBuffer> &Result, 
-                           unsigned Flags=0);
-  
+  /// to the file at the specified path.
+  static error_code create(StringRef FilePath, size_t Size,
+                           OwningPtr<FileOutputBuffer> &Result,
+                           unsigned Flags = 0);
 
   /// Returns a pointer to the start of the buffer.
-  uint8_t *getBufferStart() const {
-    return BufferStart;
+  uint8_t *getBufferStart() {
+    return (uint8_t*)Region->data();
   }
-  
+
   /// Returns a pointer to the end of the buffer.
-  uint8_t *getBufferEnd() const {
-    return BufferEnd;
+  uint8_t *getBufferEnd() {
+    return (uint8_t*)Region->data() + Region->size();
   }
-  
+
   /// Returns size of the buffer.
   size_t getBufferSize() const {
-    return BufferEnd - BufferStart;
+    return Region->size();
   }
-  
+
   /// Returns path where file will show up if buffer is committed.
   StringRef getPath() const {
     return FinalPath;
   }
-    
-  /// Flushes the content of the buffer to its file and deallocates the 
+
+  /// Flushes the content of the buffer to its file and deallocates the
   /// buffer.  If commit() is not called before this object's destructor
   /// is called, the file is deleted in the destructor. The optional parameter
   /// is used if it turns out you want the file size to be smaller than
   /// initially requested.
   error_code commit(int64_t NewSmallerSize = -1);
-  
+
   /// If this object was previously committed, the destructor just deletes
   /// this object.  If this object was not committed, the destructor
   /// deallocates the buffer and the target file is never written.
   ~FileOutputBuffer();
 
-  
 private:
   FileOutputBuffer(const FileOutputBuffer &) LLVM_DELETED_FUNCTION;
   FileOutputBuffer &operator=(const FileOutputBuffer &) LLVM_DELETED_FUNCTION;
-protected:
-  FileOutputBuffer(uint8_t *Start, uint8_t *End,
-                    StringRef Path, StringRef TempPath);
-    
-  uint8_t            *BufferStart;
-  uint8_t            *BufferEnd;
+
+  FileOutputBuffer(llvm::sys::fs::mapped_file_region *R,
+                   StringRef Path, StringRef TempPath);
+
+  OwningPtr<llvm::sys::fs::mapped_file_region> Region;
   SmallString<128>    FinalPath;
   SmallString<128>    TempPath;
 };
-
-
-
 } // end namespace llvm
 
 #endif
diff --git a/lib/Support/FileOutputBuffer.cpp b/lib/Support/FileOutputBuffer.cpp
index 46d5702cad..cd430f218b 100644
--- a/lib/Support/FileOutputBuffer.cpp
+++ b/lib/Support/FileOutputBuffer.cpp
@@ -14,34 +14,26 @@
 #include "llvm/Support/FileOutputBuffer.h"
 #include "llvm/ADT/OwningPtr.h"
 #include "llvm/ADT/SmallVector.h"
-#include "llvm/Support/FileSystem.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Support/system_error.h"
 
+using llvm::sys::fs::mapped_file_region;
 
 namespace llvm {
-
-
-FileOutputBuffer::FileOutputBuffer(uint8_t *Start, uint8_t *End, 
-                                  StringRef Path, StringRef TmpPath)
-  : BufferStart(Start), BufferEnd(End) {
-  FinalPath.assign(Path);
-  TempPath.assign(TmpPath);
+FileOutputBuffer::FileOutputBuffer(mapped_file_region * R,
+                                   StringRef Path, StringRef TmpPath)
+  : Region(R)
+  , FinalPath(Path)
+  , TempPath(TmpPath) {
 }
 
-
 FileOutputBuffer::~FileOutputBuffer() {
-  // If not already commited, delete buffer and remove temp file.
-  if ( BufferStart != NULL ) {
-    sys::fs::unmap_file_pages((void*)BufferStart, getBufferSize());
-    bool Existed;
-    sys::fs::remove(Twine(TempPath), Existed);
-  }
+  bool Existed;
+  sys::fs::remove(Twine(TempPath), Existed);
 }
 
- 
-error_code FileOutputBuffer::create(StringRef FilePath, 
-                                    size_t Size,  
+error_code FileOutputBuffer::create(StringRef FilePath,
+                                    size_t Size,
                                     OwningPtr<FileOutputBuffer> &Result,
                                     unsigned Flags) {
   // If file already exists, it must be a regular file (to be mappable).
@@ -69,34 +61,27 @@ error_code FileOutputBuffer::create(StringRef FilePath,
   EC = sys::fs::remove(FilePath, Existed);
   if (EC)
     return EC;
-  
+
   // 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::unique_file(Twine(FilePath) + ".tmp%%%%%%%",
+                            FD, TempFilePath, false, 0644);
   if (EC)
     return EC;
-  
-  // The unique_file() interface leaks lower layers and returns a file 
-  // descriptor.  There is no way to directly close it, so use this hack
-  // to hand it off to raw_fd_ostream to close for us.
-  {
-    raw_fd_ostream Dummy(FD, /*shouldClose=*/true);
-  }
-  
-  // Resize file to requested initial size
-  EC = sys::fs::resize_file(Twine(TempFilePath), Size);
+
+  OwningPtr<mapped_file_region> MappedFile(
+    new mapped_file_region(FD, mapped_file_region::readwrite, Size, 0, EC));
   if (EC)
     return EC;
-  
+
   // If requested, make the output file executable.
   if ( Flags & F_executable ) {
     sys::fs::file_status Stat2;
     EC = sys::fs::status(Twine(TempFilePath), Stat2);
     if (EC)
       return EC;
-    
+
     sys::fs::perms new_perms = Stat2.permissions();
     if ( new_perms & sys::fs::owner_read )
       new_perms |= sys::fs::owner_exe;
@@ -110,38 +95,25 @@ error_code FileOutputBuffer::create(StringRef FilePath,
       return EC;
   }
 
-  // Memory map new file.
-  void *Base;
-  EC = sys::fs::map_file_pages(Twine(TempFilePath), 0, Size, true, Base);
-  if (EC)
-    return EC;
-  
-  // Create FileOutputBuffer object to own mapped range.
-  uint8_t *Start = reinterpret_cast<uint8_t*>(Base);
-  Result.reset(new FileOutputBuffer(Start, Start+Size, FilePath, TempFilePath));
-                     
-  return error_code::success();
-}                    
+  Result.reset(new FileOutputBuffer(MappedFile.get(), FilePath, TempFilePath));
+  if (Result)
+    MappedFile.take();
 
+  return error_code::success();
+}
 
 error_code FileOutputBuffer::commit(int64_t NewSmallerSize) {
   // Unmap buffer, letting OS flush dirty pages to file on disk.
-  void *Start = reinterpret_cast<void*>(BufferStart);
-  error_code EC = sys::fs::unmap_file_pages(Start, getBufferSize());
-  if (EC)
-    return EC;
-  
+  Region.reset(0);
+
   // If requested, resize file as part of commit.
   if ( NewSmallerSize != -1 ) {
-    EC = sys::fs::resize_file(Twine(TempPath), NewSmallerSize);
+    error_code EC = sys::fs::resize_file(Twine(TempPath), NewSmallerSize);
     if (EC)
       return EC;
   }
-  
+
   // Rename file to final name.
   return sys::fs::rename(Twine(TempPath), Twine(FinalPath));
 }
-
-
 } // namespace
-
diff --git a/unittests/Support/FileOutputBufferTest.cpp b/unittests/Support/FileOutputBufferTest.cpp
index edd350afcf..4c0d57b845 100644
--- a/unittests/Support/FileOutputBufferTest.cpp
+++ b/unittests/Support/FileOutputBufferTest.cpp
@@ -7,9 +7,10 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "llvm/Support/FileOutputBuffer.h"
+
 #include "llvm/ADT/OwningPtr.h"
 #include "llvm/Support/ErrorHandling.h"
-#include "llvm/Support/FileOutputBuffer.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/PathV2.h"
 #include "llvm/Support/raw_ostream.h"
@@ -27,13 +28,6 @@ using namespace llvm::sys;
   } else {}
 
 namespace {
-
-
-// NOTE: Temporarily run this test on unix only.  Once the file mapping
-// routines are ported to Windows, this conditional can be removed.
-#if LLVM_ON_UNIX
-
-
 TEST(FileOutputBuffer, Test) {
   // Create unique temporary directory for these tests
   SmallString<128> TestDirectory;
@@ -45,7 +39,7 @@ TEST(FileOutputBuffer, Test) {
     ::close(fd);
     TestDirectory = path::parent_path(TestDirectory);
   }
-     
+
   // TEST 1: Verify commit case.
   SmallString<128> File1(TestDirectory);
 	File1.append("/file1");
@@ -61,7 +55,7 @@ TEST(FileOutputBuffer, Test) {
   }
   // Verify file exists and starts with special header.
   bool MagicMatches = false;
-  ASSERT_NO_ERROR(fs::has_magic(Twine(File1), Twine("AABBCCDDEEFFGGHHIIJJ"), 
+  ASSERT_NO_ERROR(fs::has_magic(Twine(File1), Twine("AABBCCDDEEFFGGHHIIJJ"),
                                                                 MagicMatches));
   EXPECT_TRUE(MagicMatches);
   // Verify file is correct size.
@@ -82,8 +76,7 @@ TEST(FileOutputBuffer, Test) {
   // Verify file does not exist (because buffer not commited).
   bool Exists = false;
   ASSERT_NO_ERROR(fs::exists(Twine(File2), Exists));
-  EXPECT_FALSE(Exists);  
-
+  EXPECT_FALSE(Exists);
 
   // TEST 3: Verify sizing down case.
   SmallString<128> File3(TestDirectory);
@@ -100,7 +93,7 @@ TEST(FileOutputBuffer, Test) {
   }
   // Verify file exists and starts with special header.
   bool MagicMatches3 = false;
-  ASSERT_NO_ERROR(fs::has_magic(Twine(File3), Twine("AABBCCDDEEFFGGHHIIJJ"), 
+  ASSERT_NO_ERROR(fs::has_magic(Twine(File3), Twine("AABBCCDDEEFFGGHHIIJJ"),
                                                               MagicMatches3));
   EXPECT_TRUE(MagicMatches3);
   // Verify file is correct size.
@@ -108,13 +101,12 @@ TEST(FileOutputBuffer, Test) {
   ASSERT_NO_ERROR(fs::file_size(Twine(File3), File3Size));
   ASSERT_EQ(File3Size, 5000ULL);
 
-
   // TEST 4: Verify file can be made executable.
   SmallString<128> File4(TestDirectory);
 	File4.append("/file4");
   {
     OwningPtr<FileOutputBuffer> Buffer;
-    ASSERT_NO_ERROR(FileOutputBuffer::create(File4, 8192, Buffer, 
+    ASSERT_NO_ERROR(FileOutputBuffer::create(File4, 8192, Buffer,
                                               FileOutputBuffer::F_executable));
     // Start buffer with special header.
     memcpy(Buffer->getBufferStart(), "AABBCCDDEEFFGGHHIIJJ", 20);
@@ -131,7 +123,4 @@ TEST(FileOutputBuffer, Test) {
   uint32_t RemovedCount;
   ASSERT_NO_ERROR(fs::remove_all(TestDirectory.str(), RemovedCount));
 }
-
-#endif // LLVM_ON_UNIX
-
 } // anonymous namespace