blob: 7ca4461e94f7acd8378fad753697e623b69dfc02 [file] [log] [blame]
// 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 "base/files/file.h"
#include <io.h>
#include <stdint.h>
#include "base/logging.h"
#include <windows.h>
namespace base {
// Make sure our Whence mappings match the system headers.
static_assert(File::FROM_BEGIN == FILE_BEGIN &&
File::FROM_CURRENT == FILE_CURRENT &&
File::FROM_END == FILE_END,
"whence mapping must match the system headers");
bool File::IsValid() const {
return file_.IsValid();
}
PlatformFile File::GetPlatformFile() const {
return file_.Get();
}
PlatformFile File::TakePlatformFile() {
return file_.Take();
}
void File::Close() {
if (!file_.IsValid())
return;
file_.Close();
}
int64_t File::Seek(Whence whence, int64_t offset) {
DCHECK(IsValid());
LARGE_INTEGER distance, res;
distance.QuadPart = offset;
DWORD move_method = static_cast<DWORD>(whence);
if (!SetFilePointerEx(file_.Get(), distance, &res, move_method))
return -1;
return res.QuadPart;
}
int File::Read(int64_t offset, char* data, int size) {
DCHECK(IsValid());
DCHECK(!async_);
if (size < 0)
return -1;
LARGE_INTEGER offset_li;
offset_li.QuadPart = offset;
OVERLAPPED overlapped = {0};
overlapped.Offset = offset_li.LowPart;
overlapped.OffsetHigh = offset_li.HighPart;
DWORD bytes_read;
if (::ReadFile(file_.Get(), data, size, &bytes_read, &overlapped))
return bytes_read;
if (ERROR_HANDLE_EOF == GetLastError())
return 0;
return -1;
}
int File::ReadAtCurrentPos(char* data, int size) {
DCHECK(IsValid());
DCHECK(!async_);
if (size < 0)
return -1;
DWORD bytes_read;
if (::ReadFile(file_.Get(), data, size, &bytes_read, NULL))
return bytes_read;
if (ERROR_HANDLE_EOF == GetLastError())
return 0;
return -1;
}
int File::ReadNoBestEffort(int64_t offset, char* data, int size) {
// TODO(dbeam): trace this separately?
return Read(offset, data, size);
}
int File::ReadAtCurrentPosNoBestEffort(char* data, int size) {
// TODO(dbeam): trace this separately?
return ReadAtCurrentPos(data, size);
}
int File::Write(int64_t offset, const char* data, int size) {
DCHECK(IsValid());
DCHECK(!async_);
LARGE_INTEGER offset_li;
offset_li.QuadPart = offset;
OVERLAPPED overlapped = {0};
overlapped.Offset = offset_li.LowPart;
overlapped.OffsetHigh = offset_li.HighPart;
DWORD bytes_written;
if (::WriteFile(file_.Get(), data, size, &bytes_written, &overlapped))
return bytes_written;
return -1;
}
int File::WriteAtCurrentPos(const char* data, int size) {
DCHECK(IsValid());
DCHECK(!async_);
if (size < 0)
return -1;
DWORD bytes_written;
if (::WriteFile(file_.Get(), data, size, &bytes_written, NULL))
return bytes_written;
return -1;
}
int File::WriteAtCurrentPosNoBestEffort(const char* data, int size) {
return WriteAtCurrentPos(data, size);
}
int64_t File::GetLength() {
DCHECK(IsValid());
LARGE_INTEGER size;
if (!::GetFileSizeEx(file_.Get(), &size))
return -1;
return static_cast<int64_t>(size.QuadPart);
}
bool File::SetLength(int64_t length) {
DCHECK(IsValid());
// Get the current file pointer.
LARGE_INTEGER file_pointer;
LARGE_INTEGER zero;
zero.QuadPart = 0;
if (!::SetFilePointerEx(file_.Get(), zero, &file_pointer, FILE_CURRENT))
return false;
LARGE_INTEGER length_li;
length_li.QuadPart = length;
// If length > file size, SetFilePointerEx() should extend the file
// with zeroes on all Windows standard file systems (NTFS, FATxx).
if (!::SetFilePointerEx(file_.Get(), length_li, NULL, FILE_BEGIN))
return false;
// Set the new file length and move the file pointer to its old position.
// This is consistent with ftruncate()'s behavior, even when the file
// pointer points to a location beyond the end of the file.
// TODO(rvargas): Emulating ftruncate details seem suspicious and it is not
// promised by the interface (nor was promised by PlatformFile). See if this
// implementation detail can be removed.
return ((::SetEndOfFile(file_.Get()) != FALSE) &&
(::SetFilePointerEx(file_.Get(), file_pointer, NULL, FILE_BEGIN) !=
FALSE));
}
bool File::GetInfo(Info* info) {
DCHECK(IsValid());
BY_HANDLE_FILE_INFORMATION file_info;
if (!GetFileInformationByHandle(file_.Get(), &file_info))
return false;
LARGE_INTEGER size;
size.HighPart = file_info.nFileSizeHigh;
size.LowPart = file_info.nFileSizeLow;
info->size = size.QuadPart;
info->is_directory =
(file_info.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) != 0;
info->is_symbolic_link = false; // Windows doesn't have symbolic links.
info->last_modified =
*reinterpret_cast<uint64_t*>(&file_info.ftLastWriteTime);
info->last_accessed =
*reinterpret_cast<uint64_t*>(&file_info.ftLastAccessTime);
info->creation_time = *reinterpret_cast<uint64_t*>(&file_info.ftCreationTime);
return true;
}
File::Error File::Lock() {
DCHECK(IsValid());
BOOL result = LockFile(file_.Get(), 0, 0, MAXDWORD, MAXDWORD);
if (!result)
return GetLastFileError();
return FILE_OK;
}
File::Error File::Unlock() {
DCHECK(IsValid());
BOOL result = UnlockFile(file_.Get(), 0, 0, MAXDWORD, MAXDWORD);
if (!result)
return GetLastFileError();
return FILE_OK;
}
File File::Duplicate() const {
if (!IsValid())
return File();
HANDLE other_handle = nullptr;
if (!::DuplicateHandle(GetCurrentProcess(), // hSourceProcessHandle
GetPlatformFile(),
GetCurrentProcess(), // hTargetProcessHandle
&other_handle,
0, // dwDesiredAccess ignored due to SAME_ACCESS
FALSE, // !bInheritHandle
DUPLICATE_SAME_ACCESS)) {
return File(GetLastFileError());
}
File other(other_handle);
if (async())
other.async_ = true;
return other;
}
bool File::DeleteOnClose(bool delete_on_close) {
FILE_DISPOSITION_INFO disposition = {delete_on_close ? TRUE : FALSE};
return ::SetFileInformationByHandle(GetPlatformFile(), FileDispositionInfo,
&disposition, sizeof(disposition)) != 0;
}
// Static.
File::Error File::OSErrorToFileError(DWORD last_error) {
switch (last_error) {
case ERROR_SHARING_VIOLATION:
return FILE_ERROR_IN_USE;
case ERROR_ALREADY_EXISTS:
case ERROR_FILE_EXISTS:
return FILE_ERROR_EXISTS;
case ERROR_FILE_NOT_FOUND:
case ERROR_PATH_NOT_FOUND:
return FILE_ERROR_NOT_FOUND;
case ERROR_ACCESS_DENIED:
return FILE_ERROR_ACCESS_DENIED;
case ERROR_TOO_MANY_OPEN_FILES:
return FILE_ERROR_TOO_MANY_OPENED;
case ERROR_OUTOFMEMORY:
case ERROR_NOT_ENOUGH_MEMORY:
return FILE_ERROR_NO_MEMORY;
case ERROR_HANDLE_DISK_FULL:
case ERROR_DISK_FULL:
case ERROR_DISK_RESOURCES_EXHAUSTED:
return FILE_ERROR_NO_SPACE;
case ERROR_USER_MAPPED_FILE:
return FILE_ERROR_INVALID_OPERATION;
case ERROR_NOT_READY:
case ERROR_SECTOR_NOT_FOUND:
case ERROR_DEV_NOT_EXIST:
case ERROR_IO_DEVICE:
case ERROR_FILE_CORRUPT:
case ERROR_DISK_CORRUPT:
return FILE_ERROR_IO;
default:
// This function should only be called for errors.
DCHECK_NE(static_cast<DWORD>(ERROR_SUCCESS), last_error);
return FILE_ERROR_FAILED;
}
}
void File::DoInitialize(const FilePath& path, uint32_t flags) {
DCHECK(!IsValid());
DWORD disposition = 0;
if (flags & FLAG_OPEN)
disposition = OPEN_EXISTING;
if (flags & FLAG_CREATE) {
DCHECK(!disposition);
disposition = CREATE_NEW;
}
if (flags & FLAG_OPEN_ALWAYS) {
DCHECK(!disposition);
disposition = OPEN_ALWAYS;
}
if (flags & FLAG_CREATE_ALWAYS) {
DCHECK(!disposition);
DCHECK(flags & FLAG_WRITE);
disposition = CREATE_ALWAYS;
}
if (flags & FLAG_OPEN_TRUNCATED) {
DCHECK(!disposition);
DCHECK(flags & FLAG_WRITE);
disposition = TRUNCATE_EXISTING;
}
if (!disposition) {
::SetLastError(ERROR_INVALID_PARAMETER);
error_details_ = FILE_ERROR_FAILED;
NOTREACHED();
return;
}
DWORD access = 0;
if (flags & FLAG_WRITE)
access = GENERIC_WRITE;
if (flags & FLAG_APPEND) {
DCHECK(!access);
access = FILE_APPEND_DATA;
}
if (flags & FLAG_READ)
access |= GENERIC_READ;
if (flags & FLAG_WRITE_ATTRIBUTES)
access |= FILE_WRITE_ATTRIBUTES;
if (flags & FLAG_EXECUTE)
access |= GENERIC_EXECUTE;
if (flags & FLAG_CAN_DELETE_ON_CLOSE)
access |= DELETE;
DWORD sharing = (flags & FLAG_EXCLUSIVE_READ) ? 0 : FILE_SHARE_READ;
if (!(flags & FLAG_EXCLUSIVE_WRITE))
sharing |= FILE_SHARE_WRITE;
if (flags & FLAG_SHARE_DELETE)
sharing |= FILE_SHARE_DELETE;
DWORD create_flags = 0;
if (flags & FLAG_ASYNC)
create_flags |= FILE_FLAG_OVERLAPPED;
if (flags & FLAG_TEMPORARY)
create_flags |= FILE_ATTRIBUTE_TEMPORARY;
if (flags & FLAG_HIDDEN)
create_flags |= FILE_ATTRIBUTE_HIDDEN;
if (flags & FLAG_DELETE_ON_CLOSE)
create_flags |= FILE_FLAG_DELETE_ON_CLOSE;
if (flags & FLAG_BACKUP_SEMANTICS)
create_flags |= FILE_FLAG_BACKUP_SEMANTICS;
if (flags & FLAG_SEQUENTIAL_SCAN)
create_flags |= FILE_FLAG_SEQUENTIAL_SCAN;
file_.Set(CreateFile(path.value().c_str(), access, sharing, NULL, disposition,
create_flags, NULL));
if (file_.IsValid()) {
error_details_ = FILE_OK;
async_ = ((flags & FLAG_ASYNC) == FLAG_ASYNC);
if (flags & (FLAG_OPEN_ALWAYS))
created_ = (ERROR_ALREADY_EXISTS != GetLastError());
else if (flags & (FLAG_CREATE_ALWAYS | FLAG_CREATE))
created_ = true;
} else {
error_details_ = GetLastFileError();
}
}
bool File::Flush() {
DCHECK(IsValid());
return ::FlushFileBuffers(file_.Get()) != FALSE;
}
void File::SetPlatformFile(PlatformFile file) {
file_.Set(file);
}
// static
File::Error File::GetLastFileError() {
return File::OSErrorToFileError(GetLastError());
}
} // namespace base