net: FileStream::Read/Write() to take IOBuffer* instead of char*

net/base/file_stream.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This file defines FileStream, a basic interface for reading and writing files
 // synchronously or asynchronously with support for seeking to an offset.
 // Note that even when used asynchronously, only one operation is supported at
 // a time.
 
 #ifndef NET_BASE_FILE_STREAM_H_
 #define NET_BASE_FILE_STREAM_H_
 #pragma once
 
 #include "base/memory/scoped_ptr.h"
 #include "base/platform_file.h"
 #include "net/base/completion_callback.h"
 #include "net/base/net_export.h"
 #include "net/base/net_log.h"
 
 class FilePath;
 
 namespace net {
 
+class IOBuffer;
+
 // TODO(darin): Move this to a more generic location.
 // This explicit mapping matches both FILE_ on Windows and SEEK_ on Linux.
 enum Whence {
   FROM_BEGIN   = 0,
   FROM_CURRENT = 1,
   FROM_END     = 2
 };
 
 class NET_EXPORT FileStream {
  public:
@@ skipping 46 matching lines @@
   // other words, partial reads are allowed.)  Returns the number of bytes
   // copied, 0 if at end-of-file, or an error code if the operation could
   // not be performed.
   //
   // The file must be opened with PLATFORM_FILE_ASYNC, and a non-null
   // callback must be passed to this method. If the read could not
   // complete synchronously, then ERR_IO_PENDING is returned, and the
   // callback will be notified on the current thread (via the MessageLoop)
   // when the read has completed.
   //
-  // The memory pointed to by |buf| must remain valid until the callback is
-  // notified. TODO(satorux): Use IOBuffer instead of char*.
-  //
   // It is valid to destroy or close the file stream while there is an
   // asynchronous read in progress.  That will cancel the read and allow
   // the buffer to be freed.
   //
   // It is invalid to request any asynchronous operations while there is an
   // in-flight asynchronous operation.
   //
   // This method must not be called if the stream was opened WRITE_ONLY.
-  virtual int Read(char* buf, int buf_len, const CompletionCallback& callback);
+  virtual int Read(IOBuffer* buf, int buf_len,
+                   const CompletionCallback& callback);
 
   // Call this method to read data from the current stream position
   // synchronously. Up to buf_len bytes will be copied into buf.  (In
   // other words, partial reads are allowed.)  Returns the number of bytes
   // copied, 0 if at end-of-file, or an error code if the operation could
   // not be performed.
   //
   // The file must not be opened with PLATFORM_FILE_ASYNC.
   // This method must not be called if the stream was opened WRITE_ONLY.
   virtual int ReadSync(char* buf, int buf_len);
@@ skipping 10 matching lines @@
   // other words, partial writes are allowed.)  Returns the number of
   // bytes written, or an error code if the operation could not be
   // performed.
   //
   // The file must be opened with PLATFORM_FILE_ASYNC, and a non-null
   // callback must be passed to this method. If the write could not
   // complete synchronously, then ERR_IO_PENDING is returned, and the
   // callback will be notified on the current thread (via the MessageLoop)
   // when the write has completed.
   //
-  // The memory pointed to by |buf| must remain valid until the callback
-  // is notified. TODO(satorux): Use IOBuffer instead of char*.
-  //
   // It is valid to destroy or close the file stream while there is an
   // asynchronous write in progress.  That will cancel the write and allow
   // the buffer to be freed.
   //
   // It is invalid to request any asynchronous operations while there is an
   // in-flight asynchronous operation.
   //
   // This method must not be called if the stream was opened READ_ONLY.
-  virtual int Write(const char* buf, int buf_len,
+  virtual int Write(IOBuffer* buf, int buf_len,
                     const CompletionCallback& callback);
 
   // Call this method to write data at the current stream position
   // synchronously.  Up to buf_len bytes will be written from buf. (In
   // other words, partial writes are allowed.)  Returns the number of
   // bytes written, or an error code if the operation could not be
   // performed.
   //
   // The file must not be opened with PLATFORM_FILE_ASYNC.
   // This method must not be called if the stream was opened READ_ONLY.
@@ skipping 20 matching lines @@
   void EnableErrorStatistics();
 
   // Sets the source reference for net-internals logging.
   // Creates source dependency events between |owner_bound_net_log| and
   // |bound_net_log_|.  Each gets an event showing the dependency on the other.
   // If only one of those is valid, it gets an event showing that a change
   // of ownership happened, but without details.
   void SetBoundNetLogSource(const net::BoundNetLog& owner_bound_net_log);
 
  private:
-  // Helper functions used to implement reads and writes.
-  int ReadInternal(char* buf, int buf_len,
-                   const CompletionCallback& callback);
-  int WriteInternal(const char* buf, int buf_len,
-                    const CompletionCallback& callback);
-
   class AsyncContext;
   friend class AsyncContext;
   friend class FileStreamTest;
 
   // This member is used to support asynchronous reads.  It is non-null when
   // the FileStream was opened with PLATFORM_FILE_ASYNC.
   scoped_ptr<AsyncContext> async_context_;
 
   base::PlatformFile file_;
   int open_flags_;
   bool auto_closed_;
   bool record_uma_;
   net::BoundNetLog bound_net_log_;
 
   DISALLOW_COPY_AND_ASSIGN(FileStream);
 };
 
 }  // namespace net
 
 #endif  // NET_BASE_FILE_STREAM_H_