Cleanup app snapshots on isolate/vm exit.

runtime/bin/file.h

 // Copyright (c) 2013, 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 RUNTIME_BIN_FILE_H_
 #define RUNTIME_BIN_FILE_H_
 
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/types.h>
 
 #include "bin/builtin.h"
 #include "bin/dartutils.h"
 #include "bin/log.h"
 #include "bin/reference_counting.h"
 
 namespace dart {
 namespace bin {
 
 // Forward declaration.
 class FileHandle;
 
+class MappedMemory {
+ public:
+  MappedMemory(void* address, intptr_t size) : address_(address), size_(size) {}
+  ~MappedMemory() { Unmap(); }
+
+  void* address() const { return address_; }
+  intptr_t size() const { return size_; }
+
+ private:
+  void Unmap();
+
+  void* address_;
+  intptr_t size_;
+
+  DISALLOW_COPY_AND_ASSIGN(MappedMemory);
+};
+
 class File : public ReferenceCounted<File> {
  public:
   enum FileOpenMode {
     kRead = 0,
     kWrite = 1,
     kTruncate = 1 << 2,
     kWriteOnly = 1 << 3,
     kWriteTruncate = kWrite | kTruncate,
     kWriteOnlyTruncate = kWriteOnly | kTruncate
   };
@@ skipping 42 matching lines @@
     kLockBlockingExclusive = 4,
     kLockMax = 4
   };
 
   intptr_t GetFD();
 
   enum MapType {
     kReadOnly = 0,
     kReadExecute = 1,
   };
-  void* Map(MapType type, int64_t position, int64_t length);
+  MappedMemory* Map(MapType type, int64_t position, int64_t length);
 
   // 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
   // occurred the result will be set to false.
@@ skipping 133 matching lines @@
   Dart_WeakPersistentHandle weak_handle_;
 
   friend class ReferenceCounted<File>;
   DISALLOW_COPY_AND_ASSIGN(File);
 };
 
 }  // namespace bin
 }  // namespace dart
 
 #endif  // RUNTIME_BIN_FILE_H_