Fixes some memory leaks in //runtime/bin

runtime/bin/directory.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_DIRECTORY_H_
 #define BIN_DIRECTORY_H_
 
 #include "bin/builtin.h"
 #include "bin/dartutils.h"
 #include "bin/thread.h"
 #include "platform/globals.h"
 
 
 namespace dart {
 namespace bin {
 
 enum ListType {
   kListFile = 0,
   kListDirectory = 1,
   kListLink = 2,
   kListError = 3,
   kListDone = 4
 };
 
 class PathBuffer {
  public:
   PathBuffer();
-  ~PathBuffer() {
-    free(data_);
-  }
+  ~PathBuffer();
 
   bool Add(const char* name);
   bool AddW(const wchar_t* name);
 
   char* AsString() const;
   wchar_t* AsStringW() const;
 
-  void Reset(int new_length);
+  // Makes a scope allocated copy of the string.
+  const char* AsScopedString() const;
 
-  int length() const {
+  void Reset(intptr_t new_length);
+
+  intptr_t length() const {
     return length_;
   }
 
  private:
   void* data_;
-  int length_;
+  intptr_t length_;
 
   DISALLOW_COPY_AND_ASSIGN(PathBuffer);
 };
 
 class DirectoryListing;
 
 struct LinkList;
 
 // DirectoryListingEntry is used as a stack item, when performing recursive
 // directory listing. By using DirectoryListingEntry as stack elements, a
@@ skipping 48 matching lines @@
     }
     Push(new DirectoryListingEntry(NULL));
   }
 
   virtual ~DirectoryListing() {
     while (!IsEmpty()) {
       Pop();
     }
   }
 
-  virtual bool HandleDirectory(char* dir_name) = 0;
-  virtual bool HandleFile(char* file_name) = 0;
-  virtual bool HandleLink(char* link_name) = 0;
-  virtual bool HandleError(const char* dir_name) = 0;
+  virtual bool HandleDirectory(const char* dir_name) = 0;
+  virtual bool HandleFile(const char* file_name) = 0;
+  virtual bool HandleLink(const char* link_name) = 0;
+  virtual bool HandleError() = 0;
   virtual void HandleDone() {}
 
   void Push(DirectoryListingEntry* directory) {
     top_ = directory;
   }
 
   void Pop() {
     ASSERT(!IsEmpty());
     DirectoryListingEntry* current = top_;
     top_ = top_->parent();
     delete current;
   }
 
   bool IsEmpty() const {
     return top_ == NULL;
   }
 
   DirectoryListingEntry* top() const {
     return top_;
   }
 
   bool recursive() const {
     return recursive_;
   }
 
   bool follow_links() const {
     return follow_links_;
   }
 
-  char* CurrentPath() {
-    return path_buffer_.AsString();
+  const char* CurrentPath() {
+    return path_buffer_.AsScopedString();
   }
 
   PathBuffer& path_buffer() {
     return path_buffer_;
   }
 
   bool error() const {
     return error_;
   }
 
@@ skipping 15 matching lines @@
     kListError = 3,
     kListDone = 4
   };
 
   AsyncDirectoryListing(const char* dir_name,
                         bool recursive,
                         bool follow_links)
       : DirectoryListing(dir_name, recursive, follow_links) {}
 
   virtual ~AsyncDirectoryListing() {}
-  virtual bool HandleDirectory(char* dir_name);
-  virtual bool HandleFile(char* file_name);
-  virtual bool HandleLink(char* file_name);
-  virtual bool HandleError(const char* dir_name);
+  virtual bool HandleDirectory(const char* dir_name);
+  virtual bool HandleFile(const char* file_name);
+  virtual bool HandleLink(const char* file_name);
+  virtual bool HandleError();
   virtual void HandleDone();
 
   void SetArray(CObjectArray* array, intptr_t length) {
     ASSERT(length % 2 == 0);
     array_ = array;
     index_ = 0;
     length_ = length;
   }
 
   intptr_t index() const {
     return index_;
   }
 
  private:
-  bool AddFileSystemEntityToResponse(Response response, char* arg);
+  bool AddFileSystemEntityToResponse(Response response, const char* arg);
   CObjectArray* array_;
   intptr_t index_;
   intptr_t length_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(AsyncDirectoryListing);
 };
 
 
 class SyncDirectoryListing: public DirectoryListing {
  public:
   SyncDirectoryListing(Dart_Handle results,
                        const char* dir_name,
                        bool recursive,
                        bool follow_links)
       : DirectoryListing(dir_name, recursive, follow_links),
         results_(results) {
     add_string_ = DartUtils::NewString("add");
     directory_type_ =
         DartUtils::GetDartType(DartUtils::kIOLibURL, "Directory");
     file_type_ =
         DartUtils::GetDartType(DartUtils::kIOLibURL, "File");
     link_type_ =
         DartUtils::GetDartType(DartUtils::kIOLibURL, "Link");
   }
   virtual ~SyncDirectoryListing() {}
-  virtual bool HandleDirectory(char* dir_name);
-  virtual bool HandleFile(char* file_name);
-  virtual bool HandleLink(char* file_name);
-  virtual bool HandleError(const char* dir_name);
+  virtual bool HandleDirectory(const char* dir_name);
+  virtual bool HandleFile(const char* file_name);
+  virtual bool HandleLink(const char* file_name);
+  virtual bool HandleError();
 
  private:
   Dart_Handle results_;
   Dart_Handle add_string_;
   Dart_Handle directory_type_;
   Dart_Handle file_type_;
   Dart_Handle link_type_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(SyncDirectoryListing);
 };
 
 
 class Directory {
  public:
   enum ExistsResult {
     UNKNOWN,
     EXISTS,
     DOES_NOT_EXIST
   };
 
   static void List(DirectoryListing* listing);
   static ExistsResult Exists(const char* path);
-  static char* Current();
+
+  // Returns the current working directory. The caller must call
+  // free() on the result.
+  static char* CurrentNoScope();
+
+  // Returns the current working directory. The returned string is allocated
+  // with Dart_ScopeAllocate(). It lasts only as long as the current API scope.
+  static const char* Current();
+  static const char* SystemTemp();
+  static const char* CreateTemp(const char* path);
   static bool SetCurrent(const char* path);
   static bool Create(const char* path);
-  static char* SystemTemp();
-  static char* CreateTemp(const char* path);
   static bool Delete(const char* path, bool recursive);
   static bool Rename(const char* path, const char* new_path);
 
   static CObject* CreateRequest(const CObjectArray& request);
   static CObject* DeleteRequest(const CObjectArray& request);
   static CObject* ExistsRequest(const CObjectArray& request);
   static CObject* CreateTempRequest(const CObjectArray& request);
   static CObject* CreateSystemTempRequest(const CObjectArray& request);
   static CObject* ListStartRequest(const CObjectArray& request);
   static CObject* ListNextRequest(const CObjectArray& request);
   static CObject* ListStopRequest(const CObjectArray& request);
   static CObject* RenameRequest(const CObjectArray& request);
 
  private:
   DISALLOW_ALLOCATION();
   DISALLOW_IMPLICIT_CONSTRUCTORS(Directory);
 };
 
 }  // namespace bin
 }  // namespace dart
 
 #endif  // BIN_DIRECTORY_H_