diff options
Diffstat (limited to 'vendor/golang.org/x/sys/unix/mremap.go')
-rw-r--r-- | vendor/golang.org/x/sys/unix/mremap.go | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/vendor/golang.org/x/sys/unix/mremap.go b/vendor/golang.org/x/sys/unix/mremap.go new file mode 100644 index 0000000..3a5e776 --- /dev/null +++ b/vendor/golang.org/x/sys/unix/mremap.go @@ -0,0 +1,57 @@ +// 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) +} + +func MremapPtr(oldAddr unsafe.Pointer, oldSize uintptr, newAddr unsafe.Pointer, newSize uintptr, flags int) (ret unsafe.Pointer, err error) { + xaddr, err := mapper.mremap(uintptr(oldAddr), oldSize, newSize, flags, uintptr(newAddr)) + return unsafe.Pointer(xaddr), err +} |