rustdds/structure/
duration.rs

1use std::{fmt, ops::Div};
2
3use speedy::{Readable, Writable};
4use serde::{Deserialize, Serialize};
5
6#[derive(
7  PartialEq, Eq, Hash, PartialOrd, Ord, Readable, Writable, Serialize, Deserialize, Copy, Clone,
8)]
9/// Duration is the DDS/RTPS representation for lengths of time, such as
10/// timeouts. It is very similar to [`std::time::Duration`]. See also
11/// [`Timestamp`](crate::Timestamp).
12///
13/// The resolution of `Duration` is 2^32 ticks per second.
14/// Specified (as `Duration_t`) in RTPS spec Section 9.3.2
15pub struct Duration {
16  seconds: i32,
17  fraction: u32, // unit is sec/2^32
18}
19
20impl Duration {
21  pub const ZERO: Self = Self {
22    seconds: 0,
23    fraction: 0,
24  };
25
26  pub const INFINITE: Self = Self {
27    seconds: 0x7FFFFFFF,
28    fraction: 0xFFFFFFFF,
29  };
30
31  #[deprecated(since = "0.8.7", note = "Renamed to Duration::ZERO")]
32  pub const DURATION_ZERO: Self = Self::ZERO;
33
34  #[deprecated(since = "0.8.7", note = "Renamed to Duration::INFINITE")]
35  pub const DURATION_INFINITE: Self = Self::INFINITE;
36
37  pub const fn from_secs(secs: i32) -> Self {
38    Self {
39      seconds: secs, // loss of range here
40      fraction: 0,
41    }
42  }
43
44  pub fn from_frac_seconds(secs: f64) -> Self {
45    Self {
46      seconds: secs.trunc() as i32,
47      fraction: (secs.fract().abs() * 32.0_f64.exp2()) as u32,
48    }
49  }
50
51  pub const fn from_millis(millis: i64) -> Self {
52    let fraction = (((millis % 1000) << 32) / 1000) as u32;
53
54    Self {
55      seconds: (millis / 1000) as i32,
56      fraction,
57    }
58  }
59
60  pub const fn from_nanos(nanos: i64) -> Self {
61    let fraction = (((nanos % 1_000_000_000) << 32) / 1_000_000_000) as u32;
62
63    Self {
64      seconds: (nanos / 1_000_000_000) as i32,
65      fraction,
66    }
67  }
68
69  pub(crate) fn to_ticks(self) -> i64 {
70    (i64::from(self.seconds) << 32) + i64::from(self.fraction)
71  }
72
73  pub(crate) fn from_ticks(ticks: i64) -> Self {
74    Self {
75      seconds: (ticks >> 32) as i32,
76      fraction: ticks as u32,
77    }
78  }
79
80  pub fn to_nanoseconds(&self) -> i64 {
81    ((i128::from(self.to_ticks()) * 1_000_000_000) >> 32) as i64
82  }
83
84  pub fn from_std(duration: std::time::Duration) -> Self {
85    Self::from(duration)
86  }
87
88  pub fn to_std(&self) -> std::time::Duration {
89    std::time::Duration::from(*self)
90  }
91}
92
93impl From<Duration> for chrono::Duration {
94  fn from(d: Duration) -> Self {
95    Self::nanoseconds(d.to_nanoseconds())
96  }
97}
98
99impl From<std::time::Duration> for Duration {
100  fn from(duration: std::time::Duration) -> Self {
101    Self {
102      seconds: duration.as_secs() as i32,
103      fraction: ((u64::from(duration.subsec_nanos()) << 32) / 1_000_000_000) as u32,
104    }
105  }
106}
107
108impl From<Duration> for std::time::Duration {
109  fn from(d: Duration) -> Self {
110    Self::from_nanos(
111      u64::try_from(d.to_nanoseconds()).unwrap_or(0), /* saturate to zero, because
112                                                       * std::time::Duration is unsigned */
113    )
114  }
115}
116
117impl Div<i64> for Duration {
118  type Output = Self;
119
120  fn div(self, rhs: i64) -> Self {
121    Self::from_ticks(self.to_ticks() / rhs)
122  }
123}
124
125impl std::ops::Add for Duration {
126  type Output = Self;
127  fn add(self, other: Self) -> Self {
128    Self::from_ticks(self.to_ticks() + other.to_ticks())
129  }
130}
131
132impl std::ops::Mul<Duration> for f64 {
133  type Output = Duration;
134  fn mul(self, rhs: Duration) -> Duration {
135    Duration::from_ticks((self * (rhs.to_ticks() as Self)) as i64)
136  }
137}
138
139impl fmt::Debug for Duration {
140  fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
141    if *self == Self::INFINITE {
142      write!(f, "infinite")
143    } else {
144      write!(f, "{}", self.seconds)?;
145      if self.fraction > 0 {
146        let frac = format!("{:09}", (1_000_000_000 * (self.fraction as u64)) >> 32);
147        write!(f, ".{}", frac.trim_end_matches('0'))?;
148      }
149      write!(f, " sec")
150    }
151  }
152}
153
154#[cfg(test)]
155mod tests {
156  use super::*;
157
158  serialization_test!( type = Duration,
159  {
160     duration_zero,
161      Duration::ZERO,
162      le = [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00],
163      be = [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]
164  },
165  {
166      duration_infinite,
167      Duration::INFINITE,
168      le = [0xFF, 0xFF, 0xFF, 0x7F, 0xFF, 0xFF, 0xFF, 0xFF],
169      be = [0x7F, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF]
170  },
171  {
172      duration_current_empty_fraction,
173      Duration { seconds: 1_537_045_491, fraction: 0 },
174      le = [0xF3, 0x73, 0x9D, 0x5B, 0x00, 0x00, 0x00, 0x00],
175      be = [0x5B, 0x9D, 0x73, 0xF3, 0x00, 0x00, 0x00, 0x00]
176  },
177  {
178      duration_from_wireshark,
179      Duration { seconds: 1_519_152_760, fraction: 1_328_210_046 },
180      le = [0x78, 0x6E, 0x8C, 0x5A, 0x7E, 0xE0, 0x2A, 0x4F],
181      be = [0x5A, 0x8C, 0x6E, 0x78, 0x4F, 0x2A, 0xE0, 0x7E]
182  });
183
184  const NANOS_PER_SEC: u64 = 1_000_000_000;
185
186  #[test]
187  fn convert_from_duration() {
188    let duration = std::time::Duration::from_nanos(1_519_152_761 * NANOS_PER_SEC + 328_210_046);
189    let duration: Duration = duration.into();
190
191    assert_eq!(
192      duration,
193      Duration {
194        seconds: 1_519_152_761,
195        fraction: 1_409_651_413,
196      }
197    );
198  }
199
200  #[test]
201  fn convert_to_duration() {
202    let duration = Duration {
203      seconds: 1_519_152_760,
204      fraction: 1_328_210_046,
205    };
206    let duration: std::time::Duration = duration.into();
207
208    assert_eq!(
209      duration,
210      std::time::Duration::from_nanos(1_519_152_760 * NANOS_PER_SEC + 309_247_999)
211    );
212  }
213
214  fn fmt_check(d: Duration, s: &str) {
215    assert_eq!(format!("{:?}", d), s);
216  }
217
218  #[test]
219  fn duration_format() {
220    fmt_check(Duration::from_frac_seconds(0.0), "0 sec");
221    fmt_check(Duration::from_frac_seconds(0.5), "0.5 sec");
222    fmt_check(Duration::from_frac_seconds(1.5), "1.5 sec");
223    fmt_check(Duration::from_frac_seconds(20.0), "20 sec");
224    fmt_check(Duration::from_frac_seconds(2.25), "2.25 sec");
225    fmt_check(Duration::from_frac_seconds(10.0 / 3.0), "3.333333333 sec");
226  }
227}
rustdds/structure/duration.rs

rustdds/structure/
duration.rs
