moonfire-nvr/server/base/time.rs

407 lines
13 KiB
Rust

// This file is part of Moonfire NVR, a security camera network video recorder.
// Copyright (C) 2020 The Moonfire NVR Authors; see AUTHORS and LICENSE.txt.
// SPDX-License-Identifier: GPL-v3.0-or-later WITH GPL-3.0-linking-exception.
//! Time and durations for Moonfire NVR's internal format.
use crate::{bail, err, Error};
use nom::branch::alt;
use nom::bytes::complete::{tag, take_while_m_n};
use nom::combinator::{map, map_res, opt};
use nom::sequence::{preceded, tuple};
use serde::{Deserialize, Serialize};
use std::fmt;
use std::ops;
use std::str::FromStr;
type IResult<'a, I, O> = nom::IResult<I, O, nom::error::VerboseError<&'a str>>;
pub const TIME_UNITS_PER_SEC: i64 = 90_000;
/// A time specified as 90,000ths of a second since 1970-01-01 00:00:00 UTC.
#[derive(Clone, Copy, Default, Deserialize, Eq, Ord, PartialEq, PartialOrd, Serialize)]
pub struct Time(pub i64);
/// Returns a parser for a `len`-digit non-negative number which fits into an i32.
fn fixed_len_num<'a>(len: usize) -> impl FnMut(&'a str) -> IResult<'a, &'a str, i32> {
map_res(
take_while_m_n(len, len, |c: char| c.is_ascii_digit()),
|input: &str| input.parse::<i32>(),
)
}
/// Parses `YYYY-mm-dd` into pieces.
fn parse_datepart(input: &str) -> IResult<&str, (i32, i32, i32)> {
tuple((
fixed_len_num(4),
preceded(tag("-"), fixed_len_num(2)),
preceded(tag("-"), fixed_len_num(2)),
))(input)
}
/// Parses `HH:MM[:SS[:FFFFF]]` into pieces.
fn parse_timepart(input: &str) -> IResult<&str, (i32, i32, i32, i32)> {
let (input, (hr, _, min)) = tuple((fixed_len_num(2), tag(":"), fixed_len_num(2)))(input)?;
let (input, stuff) = opt(tuple((
preceded(tag(":"), fixed_len_num(2)),
opt(preceded(tag(":"), fixed_len_num(5))),
)))(input)?;
let (sec, opt_subsec) = stuff.unwrap_or((0, None));
Ok((input, (hr, min, sec, opt_subsec.unwrap_or(0))))
}
/// Parses `Z` (UTC) or `{+,-,}HH:MM` into a time zone offset in seconds.
fn parse_zone(input: &str) -> IResult<&str, i32> {
alt((
nom::combinator::value(0, tag("Z")),
map(
tuple((
opt(nom::character::complete::one_of(&b"+-"[..])),
fixed_len_num(2),
tag(":"),
fixed_len_num(2),
)),
|(sign, hr, _, min)| {
let off = hr * 3600 + min * 60;
if sign == Some('-') {
off
} else {
-off
}
},
),
))(input)
}
impl Time {
pub const MIN: Self = Time(i64::MIN);
pub const MAX: Self = Time(i64::MAX);
pub fn new(tm: time::Timespec) -> Self {
Time(tm.sec * TIME_UNITS_PER_SEC + tm.nsec as i64 * TIME_UNITS_PER_SEC / 1_000_000_000)
}
/// Parses a time as either 90,000ths of a second since epoch or a RFC 3339-like string.
///
/// The former is 90,000ths of a second since 1970-01-01T00:00:00 UTC, excluding leap seconds.
///
/// The latter is a date such as `2006-01-02T15:04:05`, followed by an optional 90,000ths of
/// a second such as `:00001`, followed by an optional time zone offset such as `Z` or
/// `-07:00`. A missing fraction is assumed to be 0. A missing time zone offset implies the
/// local time zone.
pub fn parse(input: &str) -> Result<Self, Error> {
// First try parsing as 90,000ths of a second since epoch.
if let Ok(i) = i64::from_str(input) {
return Ok(Time(i));
}
// If that failed, parse as a time string or bust.
let (remaining, ((tm_year, tm_mon, tm_mday), opt_time, opt_zone)) = tuple((
parse_datepart,
opt(preceded(tag("T"), parse_timepart)),
opt(parse_zone),
))(input)
.map_err(|e| match e {
nom::Err::Incomplete(_) => err!(InvalidArgument, msg("incomplete")),
nom::Err::Error(e) | nom::Err::Failure(e) => {
err!(InvalidArgument, source(nom::error::convert_error(input, e)))
}
})?;
if !remaining.is_empty() {
bail!(
InvalidArgument,
msg("unexpected suffix {remaining:?} following time string")
);
}
let (tm_hour, tm_min, tm_sec, subsec) = opt_time.unwrap_or((0, 0, 0, 0));
let mut tm = time::Tm {
tm_sec,
tm_min,
tm_hour,
tm_mday,
tm_mon,
tm_year,
tm_wday: 0,
tm_yday: 0,
tm_isdst: -1,
tm_utcoff: 0,
tm_nsec: 0,
};
if tm.tm_mon == 0 {
bail!(InvalidArgument, msg("time {input:?} has month 0"));
}
tm.tm_mon -= 1;
if tm.tm_year < 1900 {
bail!(InvalidArgument, msg("time {input:?} has year before 1900"));
}
tm.tm_year -= 1900;
// The time crate doesn't use tm_utcoff properly; it just calls timegm() if tm_utcoff == 0,
// mktime() otherwise. If a zone is specified, use the timegm path and a manual offset.
// If no zone is specified, use the tm_utcoff path. This is pretty lame, but follow the
// chrono crate's lead and just use 0 or 1 to choose between these functions.
let sec = if let Some(off) = opt_zone {
tm.to_timespec().sec + i64::from(off)
} else {
tm.tm_utcoff = 1;
tm.to_timespec().sec
};
Ok(Time(sec * TIME_UNITS_PER_SEC + i64::from(subsec)))
}
/// Convert to unix seconds by floor method (rounding down).
pub fn unix_seconds(&self) -> i64 {
self.0 / TIME_UNITS_PER_SEC
}
}
impl std::str::FromStr for Time {
type Err = Error;
fn from_str(s: &str) -> Result<Self, Self::Err> {
Self::parse(s)
}
}
impl ops::Sub for Time {
type Output = Duration;
fn sub(self, rhs: Time) -> Duration {
Duration(self.0 - rhs.0)
}
}
impl ops::AddAssign<Duration> for Time {
fn add_assign(&mut self, rhs: Duration) {
self.0 += rhs.0
}
}
impl ops::Add<Duration> for Time {
type Output = Time;
fn add(self, rhs: Duration) -> Time {
Time(self.0 + rhs.0)
}
}
impl ops::Sub<Duration> for Time {
type Output = Time;
fn sub(self, rhs: Duration) -> Time {
Time(self.0 - rhs.0)
}
}
impl fmt::Debug for Time {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
// Write both the raw and display forms.
write!(f, "{} /* {} */", self.0, self)
}
}
impl fmt::Display for Time {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
let tm = time::at(time::Timespec {
sec: self.0 / TIME_UNITS_PER_SEC,
nsec: 0,
});
let zone_minutes = tm.tm_utcoff.abs() / 60;
write!(
f,
"{}:{:05}{}{:02}:{:02}",
tm.strftime("%FT%T").map_err(|_| fmt::Error)?,
self.0 % TIME_UNITS_PER_SEC,
if tm.tm_utcoff > 0 { '+' } else { '-' },
zone_minutes / 60,
zone_minutes % 60
)
}
}
/// A duration specified in 1/90,000ths of a second.
/// Durations are typically non-negative, but a `moonfire_db::db::CameraDayValue::duration` may be
/// negative.
#[derive(Clone, Copy, Default, Deserialize, Eq, Ord, PartialEq, PartialOrd, Serialize)]
pub struct Duration(pub i64);
impl Duration {
pub fn to_tm_duration(&self) -> time::Duration {
time::Duration::nanoseconds(self.0 * 100000 / 9)
}
}
impl fmt::Debug for Duration {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
// Write both the raw and display forms.
write!(f, "{} /* {} */", self.0, self)
}
}
impl fmt::Display for Duration {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
let mut seconds = self.0 / TIME_UNITS_PER_SEC;
const MINUTE_IN_SECONDS: i64 = 60;
const HOUR_IN_SECONDS: i64 = 60 * MINUTE_IN_SECONDS;
const DAY_IN_SECONDS: i64 = 24 * HOUR_IN_SECONDS;
let days = seconds / DAY_IN_SECONDS;
seconds %= DAY_IN_SECONDS;
let hours = seconds / HOUR_IN_SECONDS;
seconds %= HOUR_IN_SECONDS;
let minutes = seconds / MINUTE_IN_SECONDS;
seconds %= MINUTE_IN_SECONDS;
let mut have_written = if days > 0 {
write!(f, "{} day{}", days, if days == 1 { "" } else { "s" })?;
true
} else {
false
};
if hours > 0 {
write!(
f,
"{}{} hour{}",
if have_written { " " } else { "" },
hours,
if hours == 1 { "" } else { "s" }
)?;
have_written = true;
}
if minutes > 0 {
write!(
f,
"{}{} minute{}",
if have_written { " " } else { "" },
minutes,
if minutes == 1 { "" } else { "s" }
)?;
have_written = true;
}
if seconds > 0 || !have_written {
write!(
f,
"{}{} second{}",
if have_written { " " } else { "" },
seconds,
if seconds == 1 { "" } else { "s" }
)?;
}
Ok(())
}
}
impl std::convert::TryFrom<std::time::Duration> for Duration {
type Error = std::num::TryFromIntError;
fn try_from(value: std::time::Duration) -> Result<Self, Self::Error> {
Ok(Self(i64::try_from(value.as_nanos() * 9 / 100_000)?))
}
}
impl ops::Mul<i64> for Duration {
type Output = Self;
fn mul(self, rhs: i64) -> Self::Output {
Duration(self.0 * rhs)
}
}
impl std::ops::Neg for Duration {
type Output = Self;
fn neg(self) -> Self::Output {
Duration(-self.0)
}
}
impl ops::Add for Duration {
type Output = Duration;
fn add(self, rhs: Duration) -> Duration {
Duration(self.0 + rhs.0)
}
}
impl ops::AddAssign for Duration {
fn add_assign(&mut self, rhs: Duration) {
self.0 += rhs.0
}
}
impl ops::SubAssign for Duration {
fn sub_assign(&mut self, rhs: Duration) {
self.0 -= rhs.0
}
}
#[cfg(test)]
mod tests {
use super::{Duration, Time, TIME_UNITS_PER_SEC};
use std::convert::TryFrom;
#[test]
fn test_parse_time() {
std::env::set_var("TZ", "America/Los_Angeles");
time::tzset();
#[rustfmt::skip]
let tests = &[
("2006-01-02T15:04:05-07:00", 102261550050000),
("2006-01-02T15:04:05:00001-07:00", 102261550050001),
("2006-01-02T15:04:05-08:00", 102261874050000),
("2006-01-02T15:04:05", 102261874050000), // implied -08:00
("2006-01-02T15:04", 102261873600000), // implied -08:00
("2006-01-02T15:04:05:00001", 102261874050001), // implied -08:00
("2006-01-02T15:04:05-00:00", 102259282050000),
("2006-01-02T15:04:05Z", 102259282050000),
("2006-01-02-08:00", 102256992000000), // implied -08:00
("2006-01-02", 102256992000000), // implied -08:00
("2006-01-02Z", 102254400000000),
("102261550050000", 102261550050000),
];
for test in tests {
assert_eq!(test.1, Time::parse(test.0).unwrap().0, "parsing {}", test.0);
}
}
#[test]
fn test_format_time() {
std::env::set_var("TZ", "America/Los_Angeles");
time::tzset();
assert_eq!(
"2006-01-02T15:04:05:00000-08:00",
format!("{}", Time(102261874050000))
);
}
#[test]
fn test_display_duration() {
let tests = &[
// (output, seconds)
("0 seconds", 0),
("1 second", 1),
("1 minute", 60),
("1 minute 1 second", 61),
("2 minutes", 120),
("1 hour", 3600),
("1 hour 1 minute", 3660),
("2 hours", 7200),
("1 day", 86400),
("1 day 1 hour", 86400 + 3600),
("2 days", 2 * 86400),
];
for test in tests {
assert_eq!(test.0, format!("{}", Duration(test.1 * TIME_UNITS_PER_SEC)));
}
}
#[test]
fn test_duration_from_std_duration() {
assert_eq!(
Duration::try_from(std::time::Duration::new(1, 11111)),
Ok(Duration(90_000))
);
assert_eq!(
Duration::try_from(std::time::Duration::new(1, 11112)),
Ok(Duration(90_001))
);
assert_eq!(
Duration::try_from(std::time::Duration::new(60, 0)),
Ok(Duration(60 * TIME_UNITS_PER_SEC))
);
Duration::try_from(std::time::Duration::new(u64::MAX, 0)).unwrap_err();
}
}