Port async file operations to be using native ports instead or an isolate

runtime/bin/file.h

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef BIN_FILE_H_
 #define BIN_FILE_H_
 
 #if defined(_WIN32)
 typedef signed __int64 int64_t;
 typedef unsigned __int8 uint8_t;
@@ skipping 11 matching lines @@
 
 class File {
  public:
   enum FileOpenMode {
     kRead = 0,
     kWrite = 1,
     kTruncate = 1 << 2,
     kWriteTruncate = kWrite | kTruncate
   };
 
+  // These values have to be kept in sync with the mode values of
+  // FileMode.READ, FileMode.WRITE and FileMode.APPEND in file.dart.
+  enum DartFileOpenMode {
+    kDartRead = 0,
+    kDartWrite = 1,
+    kDartAppend = 2
+  };
+
   enum StdioHandleType {
     kTerminal = 0,
     kPipe = 1,
     kFile = 2,
     kOther = 3
   };
 
+  enum FileRequest {
+    kExistsRequest = 0,
+    kCreateRequest = 1,
+    kDeleteRequest = 2,
+    kOpenRequest = 3,
+    kFullPathRequest = 4,
+    kCloseRequest = 5,
+    kPositionRequest = 6,
+    kSetPositionRequest = 7,
+    kTruncateRequest = 8,
+    kLengthRequest = 9,
+    kFlushRequest = 10,
+    kReadByteRequest = 11,
+    kWriteByteRequest = 12,
+    kReadListRequest = 13,
+    kWriteListRequest = 14,
+    kWriteStringRequest = 15
+  };
+
   ~File();
 
   // Read/Write attempt to transfer num_bytes to/from buffer. It returns
   // the number of bytes read/written.
   int64_t Read(void* buffer, int64_t num_bytes);
   int64_t Write(const void* buffer, int64_t num_bytes);
 
   // ReadFully and WriteFully do attempt to transfer num_bytes to/from
   // the buffer. In the event of short accesses they will loop internally until
   // the whole buffer has been transferred or an error occurs. If an error
@@ skipping 36 matching lines @@
 
   static bool Exists(const char* name);
   static bool Create(const char* name);
   static bool Delete(const char* name);
   static bool IsAbsolutePath(const char* pathname);
   static char* GetCanonicalPath(const char* name);
   static const char* PathSeparator();
   static const char* StringEscapedPathSeparator();
   static StdioHandleType GetStdioHandleType(int fd);
 
+  static FileOpenMode DartModeToFileMode(DartFileOpenMode mode);
+
  private:
   File(const char* name, FileHandle* handle) : name_(name), handle_(handle) { }
   void Close();
   bool IsClosed();
 
   static const int kClosedFd = -1;
 
   const char* name_;
   // FileHandle is an OS specific class which stores data about the file.
   FileHandle* handle_;  // OS specific handle for the file.
 
   // DISALLOW_COPY_AND_ASSIGN(File).
   File(const File&);
   void operator=(const File&);
 };
 
 #endif  // BIN_FILE_H_