mirror of
https://github.com/vbatts/freezing-octo-hipster.git
synced 2024-11-24 07:55:39 +00:00
52 lines
1.4 KiB
Go
52 lines
1.4 KiB
Go
// Copyright 2023 The Go Authors. All rights reserved.
|
|
// Use of this source code is governed by a BSD-style
|
|
// license that can be found in the LICENSE file.
|
|
|
|
//go:build linux || netbsd
|
|
|
|
package unix
|
|
|
|
import "unsafe"
|
|
|
|
type mremapMmapper struct {
|
|
mmapper
|
|
mremap func(oldaddr uintptr, oldlength uintptr, newlength uintptr, flags int, newaddr uintptr) (xaddr uintptr, err error)
|
|
}
|
|
|
|
var mapper = &mremapMmapper{
|
|
mmapper: mmapper{
|
|
active: make(map[*byte][]byte),
|
|
mmap: mmap,
|
|
munmap: munmap,
|
|
},
|
|
mremap: mremap,
|
|
}
|
|
|
|
func (m *mremapMmapper) Mremap(oldData []byte, newLength int, flags int) (data []byte, err error) {
|
|
if newLength <= 0 || len(oldData) == 0 || len(oldData) != cap(oldData) || flags&mremapFixed != 0 {
|
|
return nil, EINVAL
|
|
}
|
|
|
|
pOld := &oldData[cap(oldData)-1]
|
|
m.Lock()
|
|
defer m.Unlock()
|
|
bOld := m.active[pOld]
|
|
if bOld == nil || &bOld[0] != &oldData[0] {
|
|
return nil, EINVAL
|
|
}
|
|
newAddr, errno := m.mremap(uintptr(unsafe.Pointer(&bOld[0])), uintptr(len(bOld)), uintptr(newLength), flags, 0)
|
|
if errno != nil {
|
|
return nil, errno
|
|
}
|
|
bNew := unsafe.Slice((*byte)(unsafe.Pointer(newAddr)), newLength)
|
|
pNew := &bNew[cap(bNew)-1]
|
|
if flags&mremapDontunmap == 0 {
|
|
delete(m.active, pOld)
|
|
}
|
|
m.active[pNew] = bNew
|
|
return bNew, nil
|
|
}
|
|
|
|
func Mremap(oldData []byte, newLength int, flags int) (data []byte, err error) {
|
|
return mapper.Mremap(oldData, newLength, flags)
|
|
}
|