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// 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.
#include "webkit/fileapi/local_file_stream_writer.h"
#include "base/callback.h"
#include "base/message_loop.h"
#include "net/base/file_stream.h"
#include "net/base/io_buffer.h"
#include "net/base/net_errors.h"
namespace fileapi {
namespace {
const int kOpenFlagsForWrite = base::PLATFORM_FILE_OPEN |
base::PLATFORM_FILE_WRITE |
base::PLATFORM_FILE_ASYNC;
} // namespace
LocalFileStreamWriter::LocalFileStreamWriter(const base::FilePath& file_path,
int64 initial_offset)
: file_path_(file_path),
initial_offset_(initial_offset),
has_pending_operation_(false),
weak_factory_(ALLOW_THIS_IN_INITIALIZER_LIST(this)) {}
LocalFileStreamWriter::~LocalFileStreamWriter() {
// Invalidate weak pointers so that we won't receive any callbacks from
// in-flight stream operations, which might be triggered during the file close
// in the FileStream destructor.
weak_factory_.InvalidateWeakPtrs();
// FileStream's destructor closes the file safely, since we opened the file
// by its Open() method.
}
int LocalFileStreamWriter::Write(net::IOBuffer* buf, int buf_len,
const net::CompletionCallback& callback) {
DCHECK(!has_pending_operation_);
DCHECK(cancel_callback_.is_null());
has_pending_operation_ = true;
if (stream_impl_.get()) {
int result = InitiateWrite(buf, buf_len, callback);
if (result != net::ERR_IO_PENDING)
has_pending_operation_ = false;
return result;
}
return InitiateOpen(callback,
base::Bind(&LocalFileStreamWriter::ReadyToWrite,
weak_factory_.GetWeakPtr(),
make_scoped_refptr(buf), buf_len, callback));
}
int LocalFileStreamWriter::Cancel(const net::CompletionCallback& callback) {
if (!has_pending_operation_)
return net::ERR_UNEXPECTED;
DCHECK(!callback.is_null());
cancel_callback_ = callback;
return net::ERR_IO_PENDING;
}
int LocalFileStreamWriter::Flush(const net::CompletionCallback& callback) {
DCHECK(!has_pending_operation_);
DCHECK(cancel_callback_.is_null());
// Write() is not called yet, so there's nothing to flush.
if (!stream_impl_.get())
return net::OK;
has_pending_operation_ = true;
int result = InitiateFlush(callback);
if (result != net::ERR_IO_PENDING)
has_pending_operation_ = false;
return result;
}
int LocalFileStreamWriter::InitiateOpen(
const net::CompletionCallback& error_callback,
const base::Closure& main_operation) {
DCHECK(has_pending_operation_);
DCHECK(!stream_impl_.get());
stream_impl_.reset(new net::FileStream(NULL));
return stream_impl_->Open(file_path_,
kOpenFlagsForWrite,
base::Bind(&LocalFileStreamWriter::DidOpen,
weak_factory_.GetWeakPtr(),
error_callback,
main_operation));
}
void LocalFileStreamWriter::DidOpen(
const net::CompletionCallback& error_callback,
const base::Closure& main_operation,
int result) {
DCHECK(has_pending_operation_);
DCHECK(stream_impl_.get());
if (CancelIfRequested())
return;
if (result != net::OK) {
has_pending_operation_ = false;
stream_impl_.reset(NULL);
error_callback.Run(result);
return;
}
InitiateSeek(error_callback, main_operation);
}
void LocalFileStreamWriter::InitiateSeek(
const net::CompletionCallback& error_callback,
const base::Closure& main_operation) {
DCHECK(has_pending_operation_);
DCHECK(stream_impl_.get());
if (initial_offset_ == 0) {
// No need to seek.
main_operation.Run();
return;
}
int result = stream_impl_->Seek(net::FROM_BEGIN, initial_offset_,
base::Bind(&LocalFileStreamWriter::DidSeek,
weak_factory_.GetWeakPtr(),
error_callback,
main_operation));
if (result != net::ERR_IO_PENDING) {
has_pending_operation_ = false;
error_callback.Run(result);
}
}
void LocalFileStreamWriter::DidSeek(
const net::CompletionCallback& error_callback,
const base::Closure& main_operation,
int64 result) {
DCHECK(has_pending_operation_);
if (CancelIfRequested())
return;
if (result != initial_offset_) {
// TODO(kinaba) add a more specific error code.
result = net::ERR_FAILED;
}
if (result < 0) {
has_pending_operation_ = false;
error_callback.Run(static_cast<int>(result));
return;
}
main_operation.Run();
}
void LocalFileStreamWriter::ReadyToWrite(
net::IOBuffer* buf, int buf_len,
const net::CompletionCallback& callback) {
DCHECK(has_pending_operation_);
int result = InitiateWrite(buf, buf_len, callback);
if (result != net::ERR_IO_PENDING) {
has_pending_operation_ = false;
callback.Run(result);
}
}
int LocalFileStreamWriter::InitiateWrite(
net::IOBuffer* buf, int buf_len,
const net::CompletionCallback& callback) {
DCHECK(has_pending_operation_);
DCHECK(stream_impl_.get());
return stream_impl_->Write(buf, buf_len,
base::Bind(&LocalFileStreamWriter::DidWrite,
weak_factory_.GetWeakPtr(),
callback));
}
void LocalFileStreamWriter::DidWrite(const net::CompletionCallback& callback,
int result) {
DCHECK(has_pending_operation_);
if (CancelIfRequested())
return;
has_pending_operation_ = false;
callback.Run(result);
}
int LocalFileStreamWriter::InitiateFlush(
const net::CompletionCallback& callback) {
DCHECK(has_pending_operation_);
DCHECK(stream_impl_.get());
return stream_impl_->Flush(base::Bind(&LocalFileStreamWriter::DidFlush,
weak_factory_.GetWeakPtr(),
callback));
}
void LocalFileStreamWriter::DidFlush(const net::CompletionCallback& callback,
int result) {
DCHECK(has_pending_operation_);
if (CancelIfRequested())
return;
has_pending_operation_ = false;
callback.Run(result);
}
bool LocalFileStreamWriter::CancelIfRequested() {
DCHECK(has_pending_operation_);
if (cancel_callback_.is_null())
return false;
net::CompletionCallback pending_cancel = cancel_callback_;
has_pending_operation_ = false;
cancel_callback_.Reset();
pending_cancel.Run(net::OK);
return true;
}
} // namespace fileapi
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