daemonize2/
error.rs

1// SPDX-License-Identifier: MIT OR Apache-2.0
2//
3// This file is licensed under the MIT license or the Apache License, Version 2.0, at your choice.
4//
5// Copyright 2016 Fedor Gogolev
6// Copyright 2025 Oliver Old
7//
8// Licensed under the Apache License, Version 2.0 (the "License");
9// you may not use this file except in compliance with the License.
10// You may obtain a copy of the License at
11//
12//     http://www.apache.org/licenses/LICENSE-2.0
13//
14// Unless required by applicable law or agreed to in writing, software
15// distributed under the License is distributed on an "AS IS" BASIS,
16// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
17// See the License for the specific language governing permissions and
18// limitations under the License.
19
20pub type Errno = libc::c_int;
21
22/// Error type returned by `Daemonize::start()`.
23#[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Clone, Copy)]
24#[cfg_attr(feature = "tester", derive(bincode::Encode, bincode::Decode))]
25pub struct Error(ErrorKind);
26
27impl Error {
28    pub fn kind(&self) -> ErrorKind {
29        self.0
30    }
31}
32
33/// Error kind used inside `struct Error`.
34#[derive(Debug, PartialEq, Eq, PartialOrd, Ord, Clone, Copy)]
35#[cfg_attr(feature = "tester", derive(bincode::Encode, bincode::Decode))]
36pub enum ErrorKind {
37    Fork(Errno),
38    Wait(Errno),
39    DetachSession(Errno),
40    GroupNotFound,
41    GroupContainsNul,
42    SetGroup(Errno),
43    UserNotFound,
44    UserContainsNul,
45    SetUser(Errno),
46    ChangeDirectory(Errno),
47    PathContainsNul,
48    OpenPidfile(Errno),
49    GetPidfileFlags(Errno),
50    SetPidfileFlags(Errno),
51    LockPidfile(Errno),
52    ChownPidfile(Errno),
53    OpenDevnull(Errno),
54    RedirectStreams(Errno),
55    CloseDevnull(Errno),
56    TruncatePidfile(Errno),
57    WritePid(Errno),
58    WritePidUnspecifiedError,
59    Chroot(Errno),
60}
61
62impl ErrorKind {
63    fn description(&self) -> &str {
64        match self {
65            ErrorKind::Fork(_) => "unable to fork",
66            ErrorKind::Wait(_) => "wait failed",
67            ErrorKind::DetachSession(_) => "unable to create new session",
68            ErrorKind::GroupNotFound => "unable to resolve group name to group id",
69            ErrorKind::GroupContainsNul => "group option contains NUL",
70            ErrorKind::SetGroup(_) => "unable to set group",
71            ErrorKind::UserNotFound => "unable to resolve user name to user id",
72            ErrorKind::UserContainsNul => "user option contains NUL",
73            ErrorKind::SetUser(_) => "unable to set user",
74            ErrorKind::ChangeDirectory(_) => "unable to change directory",
75            ErrorKind::PathContainsNul => "pid_file option contains NUL",
76            ErrorKind::OpenPidfile(_) => "unable to open pid file",
77            ErrorKind::GetPidfileFlags(_) => "unable get pid file flags",
78            ErrorKind::SetPidfileFlags(_) => "unable set pid file flags",
79            ErrorKind::LockPidfile(_) => "unable to lock pid file",
80            ErrorKind::ChownPidfile(_) => "unable to chown pid file",
81            ErrorKind::OpenDevnull(_) => "unable to open /dev/null",
82            ErrorKind::RedirectStreams(_) => "unable to redirect standard streams to /dev/null",
83            ErrorKind::CloseDevnull(_) => "unable to close /dev/null",
84            ErrorKind::TruncatePidfile(_) => "unable to truncate pid file",
85            ErrorKind::WritePid(_) => "unable to write self pid to pid file",
86            ErrorKind::WritePidUnspecifiedError => {
87                "unable to write self pid to pid file due to unknown reason"
88            }
89            ErrorKind::Chroot(_) => "unable to chroot into directory",
90        }
91    }
92
93    fn errno(&self) -> Option<Errno> {
94        match self {
95            ErrorKind::Fork(errno) => Some(*errno),
96            ErrorKind::Wait(errno) => Some(*errno),
97            ErrorKind::DetachSession(errno) => Some(*errno),
98            ErrorKind::GroupNotFound => None,
99            ErrorKind::GroupContainsNul => None,
100            ErrorKind::SetGroup(errno) => Some(*errno),
101            ErrorKind::UserNotFound => None,
102            ErrorKind::UserContainsNul => None,
103            ErrorKind::SetUser(errno) => Some(*errno),
104            ErrorKind::ChangeDirectory(errno) => Some(*errno),
105            ErrorKind::PathContainsNul => None,
106            ErrorKind::OpenPidfile(errno) => Some(*errno),
107            ErrorKind::GetPidfileFlags(errno) => Some(*errno),
108            ErrorKind::SetPidfileFlags(errno) => Some(*errno),
109            ErrorKind::LockPidfile(errno) => Some(*errno),
110            ErrorKind::ChownPidfile(errno) => Some(*errno),
111            ErrorKind::OpenDevnull(errno) => Some(*errno),
112            ErrorKind::RedirectStreams(errno) => Some(*errno),
113            ErrorKind::CloseDevnull(errno) => Some(*errno),
114            ErrorKind::TruncatePidfile(errno) => Some(*errno),
115            ErrorKind::WritePid(errno) => Some(*errno),
116            ErrorKind::WritePidUnspecifiedError => None,
117            ErrorKind::Chroot(errno) => Some(*errno),
118        }
119    }
120}
121
122impl std::fmt::Display for ErrorKind {
123    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
124        f.write_str(self.description())?;
125        if let Some(errno) = self.errno() {
126            write!(f, ", errno {}", errno)?
127        }
128        Ok(())
129    }
130}
131
132impl std::error::Error for ErrorKind {}
133
134impl std::fmt::Display for Error {
135    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
136        write!(f, "{}", self.kind())
137    }
138}
139
140impl std::error::Error for Error {}
141
142impl From<ErrorKind> for Error {
143    fn from(kind: ErrorKind) -> Self {
144        Self(kind)
145    }
146}
147
148pub trait Num {
149    fn is_err(&self) -> bool;
150}
151
152impl Num for i8 {
153    fn is_err(&self) -> bool {
154        *self == -1
155    }
156}
157
158impl Num for i16 {
159    fn is_err(&self) -> bool {
160        *self == -1
161    }
162}
163
164impl Num for i32 {
165    fn is_err(&self) -> bool {
166        *self == -1
167    }
168}
169
170impl Num for i64 {
171    fn is_err(&self) -> bool {
172        *self == -1
173    }
174}
175
176impl Num for isize {
177    fn is_err(&self) -> bool {
178        *self == -1
179    }
180}
181
182pub fn check_err<N: Num, F: FnOnce(Errno) -> ErrorKind>(ret: N, f: F) -> Result<N, ErrorKind> {
183    if ret.is_err() {
184        Err(f(errno::errno().into()))
185    } else {
186        Ok(ret)
187    }
188}
daemonize2/error.rs

daemonize2/
error.rs
