blob: e6ee041abbc92a82553d4a71f2e4faf055c38df9 [file] [log] [blame]
// Copyright 2019 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.
// +build darwin dragonfly freebsd linux openbsd
package ld
import (
"syscall"
)
func (out *OutBuf) Mmap(filesize uint64) error {
err := out.fallocate(filesize)
if err != nil {
// Some file systems do not support fallocate. We ignore that error as linking
// can still take place, but you might SIGBUS when you write to the mmapped
// area.
if err.Error() != fallocateNotSupportedErr {
return err
}
}
err = out.f.Truncate(int64(filesize))
if err != nil {
Exitf("resize output file failed: %v", err)
}
out.buf, err = syscall.Mmap(int(out.f.Fd()), 0, int(filesize), syscall.PROT_READ|syscall.PROT_WRITE, syscall.MAP_SHARED|syscall.MAP_FILE)
return err
}
func (out *OutBuf) munmap() {
if out.buf == nil {
return
}
syscall.Munmap(out.buf)
out.buf = nil
_, err := out.f.Seek(out.off, 0)
if err != nil {
Exitf("seek output file failed: %v", err)
}
}