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
|
//! Posix Message Queue functions
//!
//! [Further reading and details on the C API](https://man7.org/linux/man-pages/man7/mq_overview.7.html)
use crate::Result;
use crate::errno::Errno;
use libc::{self, c_char, mqd_t, size_t};
use std::ffi::CString;
use crate::sys::stat::Mode;
use std::mem;
libc_bitflags!{
pub struct MQ_OFlag: libc::c_int {
O_RDONLY;
O_WRONLY;
O_RDWR;
O_CREAT;
O_EXCL;
O_NONBLOCK;
O_CLOEXEC;
}
}
libc_bitflags!{
pub struct FdFlag: libc::c_int {
FD_CLOEXEC;
}
}
#[repr(C)]
#[derive(Clone, Copy, Debug, Eq, Hash, PartialEq)]
pub struct MqAttr {
mq_attr: libc::mq_attr,
}
// x32 compatibility
// See https://sourceware.org/bugzilla/show_bug.cgi?id=21279
#[cfg(all(target_arch = "x86_64", target_pointer_width = "32"))]
pub type mq_attr_member_t = i64;
#[cfg(not(all(target_arch = "x86_64", target_pointer_width = "32")))]
pub type mq_attr_member_t = libc::c_long;
impl MqAttr {
pub fn new(mq_flags: mq_attr_member_t,
mq_maxmsg: mq_attr_member_t,
mq_msgsize: mq_attr_member_t,
mq_curmsgs: mq_attr_member_t)
-> MqAttr
{
let mut attr = mem::MaybeUninit::<libc::mq_attr>::uninit();
unsafe {
let p = attr.as_mut_ptr();
(*p).mq_flags = mq_flags;
(*p).mq_maxmsg = mq_maxmsg;
(*p).mq_msgsize = mq_msgsize;
(*p).mq_curmsgs = mq_curmsgs;
MqAttr { mq_attr: attr.assume_init() }
}
}
pub fn flags(&self) -> mq_attr_member_t {
self.mq_attr.mq_flags
}
}
/// Open a message queue
///
/// See also [`mq_open(2)`](https://pubs.opengroup.org/onlinepubs/9699919799/functions/mq_open.html)
// The mode.bits cast is only lossless on some OSes
#[allow(clippy::cast_lossless)]
pub fn mq_open(name: &CString,
oflag: MQ_OFlag,
mode: Mode,
attr: Option<&MqAttr>)
-> Result<mqd_t> {
let res = match attr {
Some(mq_attr) => unsafe {
libc::mq_open(name.as_ptr(),
oflag.bits(),
mode.bits() as libc::c_int,
&mq_attr.mq_attr as *const libc::mq_attr)
},
None => unsafe { libc::mq_open(name.as_ptr(), oflag.bits()) },
};
Errno::result(res)
}
/// Remove a message queue
///
/// See also [`mq_unlink(2)`](https://pubs.opengroup.org/onlinepubs/9699919799/functions/mq_unlink.html)
pub fn mq_unlink(name: &CString) -> Result<()> {
let res = unsafe { libc::mq_unlink(name.as_ptr()) };
Errno::result(res).map(drop)
}
/// Close a message queue
///
/// See also [`mq_close(2)`](https://pubs.opengroup.org/onlinepubs/9699919799/functions/mq_close.html)
pub fn mq_close(mqdes: mqd_t) -> Result<()> {
let res = unsafe { libc::mq_close(mqdes) };
Errno::result(res).map(drop)
}
/// Receive a message from a message queue
///
/// See also [`mq_receive(2)`](https://pubs.opengroup.org/onlinepubs/9699919799/functions/mq_receive.html)
pub fn mq_receive(mqdes: mqd_t, message: &mut [u8], msg_prio: &mut u32) -> Result<usize> {
let len = message.len() as size_t;
let res = unsafe {
libc::mq_receive(mqdes,
message.as_mut_ptr() as *mut c_char,
len,
msg_prio as *mut u32)
};
Errno::result(res).map(|r| r as usize)
}
/// Send a message to a message queue
///
/// See also [`mq_send(2)`](https://pubs.opengroup.org/onlinepubs/9699919799/functions/mq_send.html)
pub fn mq_send(mqdes: mqd_t, message: &[u8], msq_prio: u32) -> Result<()> {
let res = unsafe {
libc::mq_send(mqdes,
message.as_ptr() as *const c_char,
message.len(),
msq_prio)
};
Errno::result(res).map(drop)
}
/// Get message queue attributes
///
/// See also [`mq_getattr(2)`](https://pubs.opengroup.org/onlinepubs/9699919799/functions/mq_getattr.html)
pub fn mq_getattr(mqd: mqd_t) -> Result<MqAttr> {
let mut attr = mem::MaybeUninit::<libc::mq_attr>::uninit();
let res = unsafe { libc::mq_getattr(mqd, attr.as_mut_ptr()) };
Errno::result(res).map(|_| unsafe{MqAttr { mq_attr: attr.assume_init() }})
}
/// Set the attributes of the message queue. Only `O_NONBLOCK` can be set, everything else will be ignored
/// Returns the old attributes
/// It is recommend to use the `mq_set_nonblock()` and `mq_remove_nonblock()` convenience functions as they are easier to use
///
/// [Further reading](https://pubs.opengroup.org/onlinepubs/9699919799/functions/mq_setattr.html)
pub fn mq_setattr(mqd: mqd_t, newattr: &MqAttr) -> Result<MqAttr> {
let mut attr = mem::MaybeUninit::<libc::mq_attr>::uninit();
let res = unsafe {
libc::mq_setattr(mqd, &newattr.mq_attr as *const libc::mq_attr, attr.as_mut_ptr())
};
Errno::result(res).map(|_| unsafe{ MqAttr { mq_attr: attr.assume_init() }})
}
/// Convenience function.
/// Sets the `O_NONBLOCK` attribute for a given message queue descriptor
/// Returns the old attributes
pub fn mq_set_nonblock(mqd: mqd_t) -> Result<MqAttr> {
let oldattr = mq_getattr(mqd)?;
let newattr = MqAttr::new(mq_attr_member_t::from(MQ_OFlag::O_NONBLOCK.bits()),
oldattr.mq_attr.mq_maxmsg,
oldattr.mq_attr.mq_msgsize,
oldattr.mq_attr.mq_curmsgs);
mq_setattr(mqd, &newattr)
}
/// Convenience function.
/// Removes `O_NONBLOCK` attribute for a given message queue descriptor
/// Returns the old attributes
pub fn mq_remove_nonblock(mqd: mqd_t) -> Result<MqAttr> {
let oldattr = mq_getattr(mqd)?;
let newattr = MqAttr::new(0,
oldattr.mq_attr.mq_maxmsg,
oldattr.mq_attr.mq_msgsize,
oldattr.mq_attr.mq_curmsgs);
mq_setattr(mqd, &newattr)
}
|
