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// Copyright (c) 2006-2008 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 "net/disk_cache/file.h"
#include <fcntl.h>
#include "base/logging.h"
#include "net/disk_cache/disk_cache.h"
namespace disk_cache {
File::File(OSFile file)
: init_(true), os_file_(file) {
}
bool File::Init(const std::wstring& name) {
if (init_)
return false;
os_file_ = CreateOSFile(name, OS_FILE_OPEN | OS_FILE_READ | OS_FILE_WRITE,
NULL);
if (os_file_ < 0) {
os_file_ = 0;
return false;
}
init_ = true;
return true;
}
File::~File() {
if (os_file_)
close(os_file_);
}
OSFile File::os_file() const {
return os_file_;
}
bool File::IsValid() const {
if (!init_)
return false;
return (INVALID_HANDLE_VALUE != os_file_);
}
bool File::Read(void* buffer, size_t buffer_len, size_t offset) {
DCHECK(init_);
if (buffer_len > ULONG_MAX || offset > LONG_MAX)
return false;
int ret = pread(os_file_, buffer, buffer_len, offset);
return (static_cast<size_t>(ret) == buffer_len);
}
bool File::Write(const void* buffer, size_t buffer_len, size_t offset) {
DCHECK(init_);
if (buffer_len > ULONG_MAX || offset > ULONG_MAX)
return false;
int ret = pwrite(os_file_, buffer, buffer_len, offset);
return (static_cast<size_t>(ret) == buffer_len);
}
// We have to increase the ref counter of the file before performing the IO to
// prevent the completion to happen with an invalid handle (if the file is
// closed while the IO is in flight).
bool File::Read(void* buffer, size_t buffer_len, size_t offset,
FileIOCallback* callback, bool* completed) {
DCHECK(init_);
if (buffer_len > ULONG_MAX || offset > ULONG_MAX)
return false;
// TODO: Implement async IO.
bool ret = Read(buffer, buffer_len, offset);
if (ret && completed)
*completed = true;
return ret;
}
bool File::Write(const void* buffer, size_t buffer_len, size_t offset,
FileIOCallback* callback, bool* completed) {
DCHECK(init_);
return AsyncWrite(buffer, buffer_len, offset, true, callback, completed);
}
bool File::PostWrite(const void* buffer, size_t buffer_len, size_t offset) {
DCHECK(init_);
return AsyncWrite(buffer, buffer_len, offset, false, NULL, NULL);
}
bool File::AsyncWrite(const void* buffer, size_t buffer_len, size_t offset,
bool notify, FileIOCallback* callback, bool* completed) {
DCHECK(init_);
if (buffer_len > ULONG_MAX || offset > ULONG_MAX)
return false;
// TODO: Implement async IO.
bool ret = Write(buffer, buffer_len, offset);
if (ret && completed)
*completed = true;
// If we supply our own async callback, and the caller is not asking to be
// notified when completed, we are supposed to delete the buffer.
if (ret && !callback && !notify)
delete[] reinterpret_cast<const char*>(buffer);
return ret;
}
bool File::SetLength(size_t length) {
DCHECK(init_);
if (length > ULONG_MAX)
return false;
return 0 == ftruncate(os_file_, length);
}
size_t File::GetLength() {
DCHECK(init_);
size_t ret = lseek(os_file_, 0, SEEK_END);
return ret;
}
} // namespace disk_cache
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