58 lines
1.3 KiB
Go
58 lines
1.3 KiB
Go
// Copyright 2017 The Go Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package main
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import (
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"bytes"
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"fmt"
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"os"
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"syscall"
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)
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func gettid() int {
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return syscall.Gettid()
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}
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func tidExists(tid int) (exists, supported bool) {
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stat, err := os.ReadFile(fmt.Sprintf("/proc/self/task/%d/stat", tid))
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if os.IsNotExist(err) {
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return false, true
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}
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// Check if it's a zombie thread.
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state := bytes.Fields(stat)[2]
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return !(len(state) == 1 && state[0] == 'Z'), true
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}
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func getcwd() (string, error) {
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if !syscall.ImplementsGetwd {
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return "", nil
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}
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// Use the syscall to get the current working directory.
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// This is imperative for checking for OS thread state
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// after an unshare since os.Getwd might just check the
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// environment, or use some other mechanism.
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var buf [4096]byte
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n, err := syscall.Getcwd(buf[:])
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if err != nil {
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return "", err
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}
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// Subtract one for null terminator.
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return string(buf[:n-1]), nil
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}
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func unshareFs() error {
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err := syscall.Unshare(syscall.CLONE_FS)
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if err != nil {
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errno, ok := err.(syscall.Errno)
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if ok && errno == syscall.EPERM {
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return errNotPermitted
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}
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}
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return err
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}
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func chdir(path string) error {
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return syscall.Chdir(path)
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}
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