| // Copyright 2016 The Fuchsia 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 freebsd || darwin |
| // +build freebsd darwin |
| |
| package osutil |
| |
| import ( |
| "os" |
| "path/filepath" |
| "runtime" |
| "syscall" |
| "unsafe" |
| ) |
| |
| // Executable returns an absolute path to the currently executing program. |
| func Executable() (string, error) { |
| var mib [4]int32 |
| switch runtime.GOOS { |
| case "freebsd": |
| mib = [4]int32{1 /* CTL_KERN */, 14 /* KERN_PROC */, 12 /* KERN_PROC_PATHNAME */, -1} |
| case "darwin": |
| mib = [4]int32{1 /* CTL_KERN */, 38 /* KERN_PROCARGS */, int32(os.Getpid()), -1} |
| } |
| |
| n := uintptr(0) |
| _, _, err := syscall.Syscall6(syscall.SYS___SYSCTL, uintptr(unsafe.Pointer(&mib[0])), 4, 0, uintptr(unsafe.Pointer(&n)), 0, 0) |
| if err != 0 { |
| return "", err |
| } |
| if n == 0 { |
| return "", nil |
| } |
| buf := make([]byte, n) |
| _, _, err = syscall.Syscall6(syscall.SYS___SYSCTL, uintptr(unsafe.Pointer(&mib[0])), 4, uintptr(unsafe.Pointer(&buf[0])), uintptr(unsafe.Pointer(&n)), 0, 0) |
| if err != 0 { |
| return "", err |
| } |
| if n == 0 { |
| return "", nil |
| } |
| for i, v := range buf { |
| if v == 0 { |
| buf = buf[:i] |
| break |
| } |
| } |
| p := string(buf) |
| if !filepath.IsAbs(p) { |
| wd, err := os.Getwd() |
| if err != nil { |
| return p, err |
| } |
| p = filepath.Join(wd, filepath.Clean(p)) |
| } |
| return filepath.EvalSymlinks(p) |
| } |