1 files changed, 53 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 00000000..fa93d0aa
--- /dev/null
+++ b/vendor/golang.org/x/sys/unix/mremap.go
@@ -0,0 +1,53 @@
+// 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
+// +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)
+}