// +build solaris

/*

* Minio Cloud Storage, (C) 2017 Minio, Inc.

*

* Licensed under the Apache License, Version 2.0 (the "License");

* you may not use this file except in compliance with the License.

* You may obtain a copy of the License at

*

* http://www.apache.org/licenses/LICENSE-2.0

*

* Unless required by applicable law or agreed to in writing, software

* distributed under the License is distributed on an "AS IS" BASIS,

* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

* See the License for the specific language governing permissions and

* limitations under the License.

*/

package lock

import (

"fmt"

"os"

"syscall"

)

// lockedOpenFile is an internal function.

func lockedOpenFile(path string, flag int, perm os.FileMode, rlockType int) (*LockedFile, error) {

var lockType int16

switch flag {

case syscall.O_RDONLY:

lockType = syscall.F_RDLCK

case syscall.O_WRONLY:

fallthrough

case syscall.O_RDWR:

fallthrough

case syscall.O_WRONLY | syscall.O_CREAT:

fallthrough

case syscall.O_RDWR | syscall.O_CREAT:

lockType = syscall.F_WRLCK

default:

return nil, fmt.Errorf("Unsupported flag (%d)", flag)

}

var lock = syscall.Flock_t{

Start: 0,

Len: 0,

Pid: 0,

Type: lockType,

Whence: 0,

}

f, err := os.OpenFile(path, flag, perm)

if err != nil {

return nil, err

}

if err = syscall.FcntlFlock(f.Fd(), rlockType, &lock); err != nil {

f.Close()

if err == syscall.EAGAIN {

err = ErrAlreadyLocked

}

return nil, err

}

st, err := os.Stat(path)

if err != nil {

f.Close()

return nil, err

}

if st.IsDir() {

f.Close()

return nil, &os.PathError{

Op: "open",

Path: path,

Err: syscall.EISDIR,

}

}

return &LockedFile{f}, nil

}

// TryLockedOpenFile - tries a new write lock, functionality

// it is similar to LockedOpenFile with with syscall.LOCK_EX

// mode but along with syscall.LOCK_NB such that the function

// doesn't wait forever but instead returns if it cannot

// acquire a write lock.

func TryLockedOpenFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {

return lockedOpenFile(path, flag, perm, syscall.F_SETLK)

}

// LockedOpenFile - initializes a new lock and protects

// the file from concurrent access across mount points.

// This implementation doesn't support all the open

// flags and shouldn't be considered as replacement

// for os.OpenFile().

func LockedOpenFile(path string, flag int, perm os.FileMode) (*LockedFile, error) {

return lockedOpenFile(path, flag, perm, syscall.F_SETLKW)

}

// Open - Call os.OpenFile

func Open(path string, flag int, perm os.FileMode) (*os.File, error) {

return os.OpenFile(path, flag, perm)

}