| // 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) |
| } |
| } |
