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/*
* Copyright (C) 2003-2015 The Music Player Daemon Project
* http://www.musicpd.org
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include "config.h"
#include "FileOutputStream.hxx"
#include "fs/FileSystem.hxx"
#include "util/Error.hxx"
FileOutputStream *
FileOutputStream::Create(Path path, Error &error)
{
FileOutputStream *f = new FileOutputStream(path, error);
if (!f->IsDefined()) {
delete f;
f = nullptr;
}
return f;
}
#ifdef WIN32
FileOutputStream::FileOutputStream(Path _path, Error &error)
:BaseFileOutputStream(_path)
{
SetHandle(CreateFile(_path.c_str(), GENERIC_WRITE, 0, nullptr,
CREATE_ALWAYS,
FILE_ATTRIBUTE_NORMAL|FILE_FLAG_WRITE_THROUGH,
nullptr));
if (!IsDefined())
error.FormatLastError("Failed to create %s",
GetPath().ToUTF8().c_str());
}
bool
BaseFileOutputStream::Write(const void *data, size_t size, Error &error)
{
assert(IsDefined());
DWORD nbytes;
if (!WriteFile(handle, data, size, &nbytes, nullptr)) {
error.FormatLastError("Failed to write to %s",
path.ToUTF8().c_str());
return false;
}
if (size_t(nbytes) != size) {
error.FormatLastError(ERROR_DISK_FULL,
"Failed to write to %s",
path.ToUTF8().c_str());
return false;
}
return true;
}
bool
FileOutputStream::Commit(gcc_unused Error &error)
{
assert(IsDefined());
Close();
return true;
}
void
FileOutputStream::Cancel()
{
assert(IsDefined());
Close();
RemoveFile(GetPath());
}
#else
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#ifdef HAVE_LINKAT
#ifndef O_TMPFILE
/* supported since Linux 3.11 */
#define __O_TMPFILE 020000000
#define O_TMPFILE (__O_TMPFILE | O_DIRECTORY)
#include <stdio.h>
#endif
/**
* Open a file using Linux's O_TMPFILE for writing the given file.
*/
static bool
OpenTempFile(FileDescriptor &fd, Path path)
{
const auto directory = path.GetDirectoryName();
if (directory.IsNull())
return false;
return fd.Open(directory.c_str(), O_TMPFILE|O_WRONLY, 0666);
}
#endif /* HAVE_LINKAT */
FileOutputStream::FileOutputStream(Path _path, Error &error)
:BaseFileOutputStream(_path)
{
#ifdef HAVE_LINKAT
/* try Linux's O_TMPFILE first */
is_tmpfile = OpenTempFile(SetFD(), GetPath());
if (!is_tmpfile) {
#endif
/* fall back to plain POSIX */
if (!SetFD().Open(GetPath().c_str(),
O_WRONLY|O_CREAT|O_TRUNC,
0666))
error.FormatErrno("Failed to create %s",
GetPath().c_str());
#ifdef HAVE_LINKAT
}
#endif
}
bool
BaseFileOutputStream::Write(const void *data, size_t size, Error &error)
{
assert(IsDefined());
ssize_t nbytes = fd.Write(data, size);
if (nbytes < 0) {
error.FormatErrno("Failed to write to %s", GetPath().c_str());
return false;
} else if ((size_t)nbytes < size) {
error.FormatErrno(ENOSPC,
"Failed to write to %s", GetPath().c_str());
return false;
}
return true;
}
bool
FileOutputStream::Commit(Error &error)
{
assert(IsDefined());
#if HAVE_LINKAT
if (is_tmpfile) {
RemoveFile(GetPath());
/* hard-link the temporary file to the final path */
char fd_path[64];
snprintf(fd_path, sizeof(fd_path), "/proc/self/fd/%d",
GetFD().Get());
if (linkat(AT_FDCWD, fd_path, AT_FDCWD, GetPath().c_str(),
AT_SYMLINK_FOLLOW) < 0) {
error.FormatErrno("Failed to commit %s",
GetPath().c_str());
Close();
return false;
}
}
#endif
bool success = Close();
if (!success)
error.FormatErrno("Failed to commit %s", GetPath().c_str());
return success;
}
void
FileOutputStream::Cancel()
{
assert(IsDefined());
Close();
#ifdef HAVE_LINKAT
if (!is_tmpfile)
#endif
RemoveFile(GetPath());
}
#ifdef WIN32
FileOutputStream::FileOutputStream(Path _path, Error &error)
:path(_path),
handle(CreateFile(path.c_str(), GENERIC_WRITE, 0, nullptr,
CREATE_ALWAYS,
FILE_ATTRIBUTE_NORMAL|FILE_FLAG_WRITE_THROUGH,
nullptr))
{
if (handle == INVALID_HANDLE_VALUE) {
const auto path_utf8 = path.ToUTF8();
error.FormatLastError("Failed to create %s",
path_utf8.c_str());
}
}
#else
AppendFileOutputStream::AppendFileOutputStream(Path _path, Error &error)
:BaseFileOutputStream(_path)
{
#ifdef WIN32
SetHandle(CreateFile(path.c_str(), GENERIC_WRITE, 0, nullptr,
OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL|FILE_FLAG_WRITE_THROUGH,
nullptr))
if (!IsDefined())
error.FormatLastError("Failed to append to %s",
GetPath().ToUTF8().c_str());
#else
if (!SetFD().Open(GetPath().c_str(),
O_WRONLY|O_APPEND))
error.FormatErrno("Failed to append to %s",
GetPath().c_str());
#endif
}
#endif
bool
AppendFileOutputStream::Commit(gcc_unused Error &error)
{
assert(IsDefined());
#ifdef WIN32
return Close();
#else
bool success = Close();
if (!success)
error.FormatErrno("Failed to commit %s", GetPath().c_str());
return success;
#endif
}
#endif
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