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
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
#![deny(unsafe_code)]
use super::rlim_type::{RawRlim, Rlim};
use std::fs;
use std::io::{self, BufRead};
use std::num::ParseIntError;
use std::path::Path;
use libc::pid_t;
#[derive(Debug, Clone, Default)]
#[non_exhaustive]
pub struct ProcLimits {
pub max_cpu_time: Option<ProcLimit>,
pub max_file_size: Option<ProcLimit>,
pub max_data_size: Option<ProcLimit>,
pub max_stack_size: Option<ProcLimit>,
pub max_core_file_size: Option<ProcLimit>,
pub max_resident_set: Option<ProcLimit>,
pub max_processes: Option<ProcLimit>,
pub max_open_files: Option<ProcLimit>,
pub max_locked_memory: Option<ProcLimit>,
pub max_address_space: Option<ProcLimit>,
pub max_file_locks: Option<ProcLimit>,
pub max_pending_signals: Option<ProcLimit>,
pub max_msgqueue_size: Option<ProcLimit>,
pub max_nice_priority: Option<ProcLimit>,
pub max_realtime_priority: Option<ProcLimit>,
pub max_realtime_timeout: Option<ProcLimit>,
}
#[derive(Debug, Clone, Default, PartialEq, Eq)]
pub struct ProcLimit {
pub soft_limit: Option<Rlim>,
pub hard_limit: Option<Rlim>,
}
impl ProcLimits {
pub fn read_self() -> io::Result<Self> {
Self::read_proc_fs("/proc/self/limits")
}
pub fn read_process(pid: pid_t) -> io::Result<Self> {
if pid < 0 {
return Err(io::Error::new(
io::ErrorKind::InvalidInput,
"ProcLimits: pid must be non-negative",
));
}
Self::read_proc_fs(format!("/proc/{}/limits", pid))
}
fn read_proc_fs(limits_path: impl AsRef<Path>) -> io::Result<Self> {
fn parse_head(head: &str) -> Option<(usize, usize, usize)> {
let s_idx = head.find('S')?;
let h_idx = head[s_idx..].find('H')?;
let u_idx = head[s_idx + h_idx..].find('U')?;
Some((s_idx, h_idx, u_idx))
}
fn parse_limit_number(s: &str) -> Result<Option<Rlim>, ParseIntError> {
match s {
"unlimited" => Ok(None),
_ => match s.parse::<RawRlim>() {
Ok(n) => Ok(Some(Rlim::from_raw(n))),
Err(e) => Err(e),
},
}
}
fn error_missing_table_head() -> io::Error {
io::Error::new(io::ErrorKind::Other, "ProcLimits: missing table head")
}
fn error_invalid_table_head() -> io::Error {
io::Error::new(io::ErrorKind::Other, "ProcLimits: invalid table head")
}
fn error_invalid_limit_number(e: ParseIntError) -> io::Error {
let ans = io::Error::new(
io::ErrorKind::Other,
format!("ProcLimits: invalid limit number: {}", e),
);
drop(e);
ans
}
fn error_duplicate_limit_field() -> io::Error {
io::Error::new(io::ErrorKind::Other, "ProcLimits: duplicate limit field")
}
fn error_unknown_limit_field(s: &str) -> io::Error {
io::Error::new(
io::ErrorKind::Other,
format!("ProcLimits: unknown limit field: {:?}", s),
)
}
let reader = io::BufReader::new(fs::File::open(limits_path)?);
let mut lines = reader.lines();
let head = lines.next().ok_or_else(error_missing_table_head)??;
let (name_len, soft_len, hard_len) =
parse_head(&head).ok_or_else(error_invalid_table_head)?;
let mut ans = Self::default();
let sorted_table: [(&str, &mut Option<ProcLimit>); 16] = [
("max address space", &mut ans.max_address_space),
("max core file size", &mut ans.max_core_file_size),
("max cpu time", &mut ans.max_cpu_time),
("max data size", &mut ans.max_data_size),
("max file locks", &mut ans.max_file_locks),
("max file size", &mut ans.max_file_size),
("max locked memory", &mut ans.max_locked_memory),
("max msgqueue size", &mut ans.max_msgqueue_size),
("max nice priority", &mut ans.max_nice_priority),
("max open files", &mut ans.max_open_files),
("max pending signals", &mut ans.max_pending_signals),
("max processes", &mut ans.max_processes),
("max realtime priority", &mut ans.max_realtime_priority),
("max realtime timeout", &mut ans.max_realtime_timeout),
("max resident set", &mut ans.max_resident_set),
("max stack size", &mut ans.max_stack_size),
];
for line in lines {
let line = line?;
let (name, line) = line.split_at(name_len);
let (soft, line) = line.split_at(soft_len);
let (hard, _) = line.split_at(hard_len);
let name = name.trim().to_lowercase();
let soft_limit = parse_limit_number(soft.trim()).map_err(error_invalid_limit_number)?;
let hard_limit = parse_limit_number(hard.trim()).map_err(error_invalid_limit_number)?;
let limit = ProcLimit {
soft_limit,
hard_limit,
};
match sorted_table.binary_search_by_key(&name.as_str(), |&(s, _)| s) {
Ok(idx) => {
let field = &mut *sorted_table[idx].1;
if field.is_some() {
return Err(error_duplicate_limit_field());
}
*field = Some(limit)
}
Err(_) => return Err(error_unknown_limit_field(&name)),
}
}
Ok(ans)
}
}