Files
adler32
aho_corasick
alga
approx
ascii
atty
backtrace
backtrace_sys
base64
bitflags
blas_src
block_buffer
block_padding
brotli2
brotli_sys
buf_redux
byte_tools
byteorder
cauchy
cblas_sys
cfg_if
chrono
chunked_transfer
colored
crc32fast
crossbeam
crossbeam_channel
crossbeam_deque
crossbeam_epoch
crossbeam_queue
crossbeam_utils
ctrlc
deflate
digest
dirs
error_chain
filetime
futures
generic_array
getrandom
gzip_header
hex
httparse
hyper
idna
itoa
language_tags
lapack_src
lapacke
lapacke_sys
lazy_static
libc
libm
linked_hash_map
log
matches
matrixmultiply
maybe_uninit
md5
memchr
memoffset
mime
mime_guess
multipart
nalgebra
base
geometry
linalg
ndarray
ndarray_linalg
net2
netlib_src
nix
num_complex
num_cpus
num_integer
num_rational
num_traits
opaque_debug
percent_encoding
phf
phf_shared
ppv_lite86
proc_macro2
quick_error
quote
rand
rand_chacha
rand_core
rand_distr
rawpointer
regex
regex_syntax
remove_dir_all
rosrust
rosrust_codegen
rosrust_msg
rouille
rustc_demangle
rustros_tf
ryu
safemem
scopeguard
serde
serde_bytes
serde_derive
serde_json
serde_xml_rs
sha1
siphasher
smallvec
syn
tempdir
term
thread_local
threadpool
time
tiny_http
traitobject
twoway
typeable
typenum
ucd_util
unicase
unicode_bidi
unicode_normalization
unicode_xid
url
utf8_ranges
void
xml
xml_rpc
yaml_rust
  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
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
// This is a part of Chrono.
// See README.md and LICENSE.txt for details.

//! The local (system) time zone.

use oldtime;

use {Datelike, Timelike};
use naive::{NaiveDate, NaiveTime, NaiveDateTime};
use {Date, DateTime};
use super::{TimeZone, LocalResult};
use super::fixed::FixedOffset;

/// Converts a `time::Tm` struct into the timezone-aware `DateTime`.
/// This assumes that `time` is working correctly, i.e. any error is fatal.
fn tm_to_datetime(mut tm: oldtime::Tm) -> DateTime<Local> {
    if tm.tm_sec >= 60 {
        tm.tm_nsec += (tm.tm_sec - 59) * 1_000_000_000;
        tm.tm_sec = 59;
    }

    #[cfg(not(windows))]
    fn tm_to_naive_date(tm: &oldtime::Tm) -> NaiveDate {
        // from_yo is more efficient than from_ymd (since it's the internal representation).
        NaiveDate::from_yo(tm.tm_year + 1900, tm.tm_yday as u32 + 1)
    }

    #[cfg(windows)]
    fn tm_to_naive_date(tm: &oldtime::Tm) -> NaiveDate {
        // ...but tm_yday is broken in Windows (issue #85)
        NaiveDate::from_ymd(tm.tm_year + 1900, tm.tm_mon as u32 + 1, tm.tm_mday as u32)
    }

    let date = tm_to_naive_date(&tm);
    let time = NaiveTime::from_hms_nano(tm.tm_hour as u32, tm.tm_min as u32,
                                        tm.tm_sec as u32, tm.tm_nsec as u32);
    let offset = FixedOffset::east(tm.tm_utcoff);
    DateTime::from_utc(date.and_time(time) - offset, offset)
}

/// Converts a local `NaiveDateTime` to the `time::Timespec`.
fn datetime_to_timespec(d: &NaiveDateTime, local: bool) -> oldtime::Timespec {
    // well, this exploits an undocumented `Tm::to_timespec` behavior
    // to get the exact function we want (either `timegm` or `mktime`).
    // the number 1 is arbitrary but should be non-zero to trigger `mktime`.
    let tm_utcoff = if local {1} else {0};

    let tm = oldtime::Tm {
        tm_sec: d.second() as i32,
        tm_min: d.minute() as i32,
        tm_hour: d.hour() as i32,
        tm_mday: d.day() as i32,
        tm_mon: d.month0() as i32, // yes, C is that strange...
        tm_year: d.year() - 1900, // this doesn't underflow, we know that d is `NaiveDateTime`.
        tm_wday: 0, // to_local ignores this
        tm_yday: 0, // and this
        tm_isdst: -1,
        tm_utcoff: tm_utcoff,
        // do not set this, OS APIs are heavily inconsistent in terms of leap second handling
        tm_nsec: 0,
    };

    tm.to_timespec()
}

/// The local timescale. This is implemented via the standard `time` crate.
///
/// Using the [`TimeZone`](./trait.TimeZone.html) methods
/// on the Local struct is the preferred way to construct `DateTime<Local>`
/// instances.
///
/// # Example
///
/// ~~~~
/// use chrono::{Local, DateTime, TimeZone};
///
/// let dt: DateTime<Local> = Local::now();
/// let dt: DateTime<Local> = Local.timestamp(0, 0);
/// ~~~~
#[derive(Copy, Clone, Debug)]
pub struct Local;

impl Local {
    /// Returns a `Date` which corresponds to the current date.
    pub fn today() -> Date<Local> {
        Local::now().date()
    }

    /// Returns a `DateTime` which corresponds to the current date.
    #[cfg(not(all(target_arch = "wasm32", not(target_os = "wasi"), feature = "wasmbind")))]
    pub fn now() -> DateTime<Local> {
        tm_to_datetime(oldtime::now())
    }

    /// Returns a `DateTime` which corresponds to the current date.
    #[cfg(all(target_arch = "wasm32", not(target_os = "wasi"), feature = "wasmbind"))]
    pub fn now() -> DateTime<Local> {
        use super::Utc;
        let now: DateTime<Utc> = super::Utc::now();

        // Workaround missing timezone logic in `time` crate
        let offset = FixedOffset::west((js_sys::Date::new_0().get_timezone_offset() as i32) * 60);
        DateTime::from_utc(now.naive_utc(), offset)
    }
}

impl TimeZone for Local {
    type Offset = FixedOffset;

    fn from_offset(_offset: &FixedOffset) -> Local { Local }

    // they are easier to define in terms of the finished date and time unlike other offsets
    fn offset_from_local_date(&self, local: &NaiveDate) -> LocalResult<FixedOffset> {
        self.from_local_date(local).map(|date| *date.offset())
    }

    fn offset_from_local_datetime(&self, local: &NaiveDateTime) -> LocalResult<FixedOffset> {
        self.from_local_datetime(local).map(|datetime| *datetime.offset())
    }

    fn offset_from_utc_date(&self, utc: &NaiveDate) -> FixedOffset {
        *self.from_utc_date(utc).offset()
    }

    fn offset_from_utc_datetime(&self, utc: &NaiveDateTime) -> FixedOffset {
        *self.from_utc_datetime(utc).offset()
    }

    // override them for avoiding redundant works
    fn from_local_date(&self, local: &NaiveDate) -> LocalResult<Date<Local>> {
        // this sounds very strange, but required for keeping `TimeZone::ymd` sane.
        // in the other words, we use the offset at the local midnight
        // but keep the actual date unaltered (much like `FixedOffset`).
        let midnight = self.from_local_datetime(&local.and_hms(0, 0, 0));
        midnight.map(|datetime| Date::from_utc(*local, *datetime.offset()))
    }

    fn from_local_datetime(&self, local: &NaiveDateTime) -> LocalResult<DateTime<Local>> {
        let timespec = datetime_to_timespec(local, true);

        // datetime_to_timespec completely ignores leap seconds, so we need to adjust for them
        let mut tm = oldtime::at(timespec);
        assert_eq!(tm.tm_nsec, 0);
        tm.tm_nsec = local.nanosecond() as i32;

        LocalResult::Single(tm_to_datetime(tm))
    }

    fn from_utc_date(&self, utc: &NaiveDate) -> Date<Local> {
        let midnight = self.from_utc_datetime(&utc.and_hms(0, 0, 0));
        Date::from_utc(*utc, *midnight.offset())
    }

    fn from_utc_datetime(&self, utc: &NaiveDateTime) -> DateTime<Local> {
        let timespec = datetime_to_timespec(utc, false);

        // datetime_to_timespec completely ignores leap seconds, so we need to adjust for them
        let mut tm = oldtime::at(timespec);
        assert_eq!(tm.tm_nsec, 0);
        tm.tm_nsec = utc.nanosecond() as i32;

        tm_to_datetime(tm)
    }
}

#[cfg(test)]
mod tests {
    use Datelike;
    use offset::TimeZone;
    use super::Local;

    #[test]
    fn test_local_date_sanity_check() { // issue #27
        assert_eq!(Local.ymd(2999, 12, 28).day(), 28);
    }

    #[test]
    fn test_leap_second() { // issue #123
        let today = Local::today();

        let dt = today.and_hms_milli(1, 2, 59, 1000);
        let timestr = dt.time().to_string();
        // the OS API may or may not support the leap second,
        // but there are only two sensible options.
        assert!(timestr == "01:02:60" || timestr == "01:03:00",
                "unexpected timestr {:?}", timestr);

        let dt = today.and_hms_milli(1, 2, 3, 1234);
        let timestr = dt.time().to_string();
        assert!(timestr == "01:02:03.234" || timestr == "01:02:04.234",
                "unexpected timestr {:?}", timestr);
    }
}