1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
|
//! Tests that repeatedly spawning a failing command does not create zombie processes.
//! Spawns a deliberately invalid command multiple times, verifies each spawn fails,
//! then uses `ps` (on Unix) to detect any leftover zombie (defunct) child processes.
//! Checks Rust's process spawning cleans up resources properly.
//! Skipped on platforms without `ps` utility.
//@ run-pass
//@ needs-subprocess
//@ ignore-vxworks no 'ps'
//@ ignore-fuchsia no 'ps'
//@ ignore-nto no 'ps'
//@ ignore-ios no 'ps'
//@ ignore-tvos no 'ps'
//@ ignore-watchos no 'ps'
//@ ignore-visionos no 'ps'
#![feature(rustc_private)]
use std::process::Command;
// The output from "ps -A -o pid,ppid,args" should look like this:
// PID PPID COMMAND
// 1 0 /sbin/init
// 2 0 [kthreadd]
// ...
// 6076 9064 /bin/zsh
// ...
// 7164 6076 ./spawn-failure
// 7165 7164 [spawn-failure] <defunct>
// 7166 7164 [spawn-failure] <defunct>
// ...
// 7197 7164 [spawn-failure] <defunct>
// 7198 7164 ps -A -o pid,ppid,command
// ...
#[cfg(unix)]
fn find_zombies() {
extern crate libc;
let my_pid = unsafe { libc::getpid() };
// https://pubs.opengroup.org/onlinepubs/9699919799/utilities/ps.html
let ps_cmd_output = Command::new("ps").args(&["-A", "-o", "pid,ppid,args"]).output().unwrap();
let ps_output = String::from_utf8_lossy(&ps_cmd_output.stdout);
// On AIX, the PPID is not always present, such as when a process is blocked
// (marked as <exiting>), or if a process is idle. In these situations,
// the PPID column contains a "-" for the respective process.
// Filter out any lines that have a "-" as the PPID as the PPID is
// expected to be an integer.
let filtered_ps: Vec<_> =
ps_output.lines().filter(|line| line.split_whitespace().nth(1) != Some("-")).collect();
for (line_no, line) in filtered_ps.into_iter().enumerate() {
if 0 < line_no
&& 0 < line.len()
&& my_pid
== line
.split(' ')
.filter(|w| 0 < w.len())
.nth(1)
.expect("1st column should be PPID")
.parse()
.ok()
.expect("PPID string into integer")
&& line.contains("defunct")
{
panic!("Zombie child {}", line);
}
}
}
#[cfg(windows)]
fn find_zombies() {}
fn main() {
let too_long = format!("/NoSuchCommand{:0300}", 0u8);
let _failures = (0..100)
.map(|_| {
let mut cmd = Command::new(&too_long);
let failed = cmd.spawn();
assert!(failed.is_err(), "Make sure the command fails to spawn(): {:?}", cmd);
failed
})
.collect::<Vec<_>>();
find_zombies();
// then _failures goes out of scope
}
|
