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
#![deny(missing_docs)]
extern crate libc;
#[derive(Debug)]
pub enum PowerState {
Standby,
Idle,
Active,
Unknown,
}
#[derive(Debug)]
pub enum Error {
NoAccess,
InvalidDeviceFile,
}
const IOCTL_DRIVE_CMD: libc::c_ulong = 0x031F;
const ATA_CHECKPOWERMODE: libc::c_uchar = 0xE5;
const ATA_CHECKPOWERMODE_RETIRED: libc::c_uchar = 0x98;
pub fn get_power_state(path: &str) -> Result<PowerState, Error> {
let device = try!(DeviceWrapper::open(path));
let mut query: [libc::c_uchar; 4] = [0; 4];
unsafe {
query[0] = ATA_CHECKPOWERMODE;
if libc::ioctl(device.fd(), IOCTL_DRIVE_CMD, query.as_mut_ptr()) != 0 {
query[0] = ATA_CHECKPOWERMODE_RETIRED;
if libc::ioctl(device.fd(), IOCTL_DRIVE_CMD, query.as_mut_ptr()) != 0 {
return Err(Error::InvalidDeviceFile)
}
}
}
Ok(match query[2] {
0x00 ... 0x01 => PowerState::Standby,
0x80 ... 0x83 => PowerState::Idle,
0xFF => PowerState::Active,
_ => PowerState::Unknown
})
}
struct DeviceWrapper(libc::c_int);
impl DeviceWrapper {
pub fn open(path: &str) -> Result<DeviceWrapper, Error> {
let path = std::ffi::CString::new(path).unwrap();
let fd = unsafe {
libc::open(path.as_ptr(), libc::O_RDONLY | libc::O_NONBLOCK)
};
if fd != -1 {
Ok(DeviceWrapper(fd))
} else {
Err(Error::NoAccess)
}
}
pub fn fd(&self) -> libc::c_int {
self.0
}
}
impl Drop for DeviceWrapper {
fn drop(&mut self) {
unsafe {
libc::close(self.0);
}
}
}