libc: new date apis

The current date and time APIs on Plan 9 are not good. They're
inflexible, non-threadsafe, and don't expose timezone information.

This commit adds new time APIs that allow parsing arbitrary
dates, work from multiple threads, and can handle timezones
effectively.
This commit is contained in:
Ori Bernstein 2020-08-09 18:58:44 -07:00
parent 3ba1d83d20
commit 56e869ac70
6 changed files with 1329 additions and 488 deletions

View file

@ -314,22 +314,44 @@ extern double fmod(double, double);
/* /*
* Time-of-day * Time-of-day
*/ */
typedef struct Tzone Tzone;
#pragma incomplete Tzone
typedef typedef
struct Tm struct Tm
{ {
int sec; int nsec; /* nseconds (range 0...1e9) */
int min; int sec; /* seconds (range 0..60) */
int hour; int min; /* minutes (0..59) */
int mday; int hour; /* hours (0..23) */
int mon; int mday; /* day of the month (1..31) */
int year; int mon; /* month of the year (0..11) */
int wday; int year; /* year A.D. */
int yday; int wday; /* day of week (0..6, Sunday = 0) */
char zone[4]; int yday; /* day of year (0..365) */
int tzoff; char zone[16]; /* time zone name */
int tzoff; /* time zone delta from GMT */
Tzone *tz; /* time zone associated with this date */
} Tm; } Tm;
typedef
struct Tmfmt {
char *fmt;
Tm *tm;
} Tmfmt;
#pragma varargck type "τ" Tmfmt
extern Tzone* tzload(char *name);
extern Tm* tmnow(Tm*, Tzone*);
extern Tm* tmtime(Tm*, vlong, Tzone*);
extern Tm* tmtimens(Tm*, vlong, int, Tzone*);
extern Tm* tmparse(Tm*, char*, char*, Tzone*, char **ep);
extern vlong tmnorm(Tm*);
extern Tmfmt tmfmt(Tm*, char*);
extern void tmfmtinstall(void);
extern Tm* gmtime(long); extern Tm* gmtime(long);
extern Tm* localtime(long); extern Tm* localtime(long);
extern char* asctime(Tm*); extern char* asctime(Tm*);

275
sys/man/2/tmdate Normal file
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@ -0,0 +1,275 @@
.TH TMDATE 2
.SH NAME
tmnow, tzload, tmtime, tmparse, tmfmt, tmnorm - convert date and time
.SH SYNOPSIS
.B #include <u.h>
.br
.B #include <libc.h>
.PP
.ft L
.nf
.EX
typedef struct Tmd Tmd;
typedef struct Tmfmt Tmfmt;
struct {
int nsec; /* nanoseconds (range 0..1e9) */
int sec; /* seconds (range 0..59) */
int min; /* minutes (0..59) */
int hour; /* hours (0..23) */
int mday; /* day of the month (1..31) */
int mon; /* month of the year (0..11) */
int year; /* C.E year - 1900 */
int wday; /* day of week (0..6, Sunday = 0) */
int yday; /* day of year (0..365) */
char zone[]; /* time zone name */
int tzoff; /* time zone delta from GMT, seconds */
};
Tzone *tzload(char *name);
Tm *tmnow(Tm *tm, char *tz);
Tm *tmtime(Tm *tm, vlong abs, Tzone *tz);
Tm *tmtimens(Tm *tm, vlong abs, int ns, Tzone *tz);
Tm *tmparse(Tm *dst, char *fmt, char *tm, Tzone *zone, char **ep);
vlong tmnorm(Tm *tm);
Tmfmt tmfmt(Tm *tm, char *fmt);
void tmfmtinstall(void);
.EE
.SH DESCRIPTION
.PP
This family of functions handles simple date and time manipulation.
.PP
Time zones are loaded by name.
They can be specified as the abbreviated timezone name,
the full timezone name, the path to a timezone file,
or an absolute offset in the HHMM form.
.PP
When given as a timezone, any instant-dependent adjustments such as leap
seconds and daylight savings time will be applied to the derived fields of
struct Tm, but will not affect the absolute time.
The time zone name local always refers to the time in /env/timezone.
The nil timezone always refers to GMT.
.PP
Tzload loads a timezone by name. The returned timezone is
cached for the lifetime of the program, and should not be freed.
Loading a timezone repeatedly by name loads from the cache, and
does not leak.
.PP
Tmnow gets the current time of day in the requested time zone.
.PP
Tmtime converts the millisecond-resolution timestamp 'abs'
into a Tm struct in the requested timezone.
Tmtimens does the same, but with a nanosecond accuracy.
.PP
Tmstime is identical to tmtime, but accepts the time in sec-
onds.
.PP
Tmparse parses a time from a string according to the format argument.
The point at which the parsing stopped is returned in
.IR ep .
If
.I ep
is nil, trailing garbage is ignored.
The result is returned in the timezone requested.
If there is a timezone in the date, and a timezone is provided
when parsing, then the zone is shifted to the provided timezone.
Parsing is case-insensitive
.PP
The format argument contains zero or more of the following components:
.TP
.B Y, YY, YYYY
Represents the year.
.I YY
prints the year in 2 digit form.
.TP
.B M, MM, MMM, MMMM
The month of the year, in unpadded numeric, padded numeric, short name, or long name,
respectively.
.TP
.B D, DD
The day of month in unpadded or padded numeric form, respectively.
.TP
.B W, WW, WWW
The day of week in numeric, short or long name form, respectively.
.TP
.B h, hh
The hour in unpadded or padded form, respectively
.TP
.B m, mm
The minute in unpadded or padded form, respectively
.TP
.B s, ss
The second in unpadded or padded form, respectively
.TP
.B t, tt
The milliseconds in unpadded and padded form, respectively.
.B u, uu, uuu, uuuu
The microseconds in unpadded. padded form modulo milliseconds,
or unpadded, padded forms of the complete value, respectively.
.B n, nn, nnn, nnnn, nnnnn, nnnnnn
The nanoseconds in unpadded and padded form modulo milliseconds,
the unpadded and padded form modulo microseconds,
and the unpadded and padded complete value, respectively.
.TP
.B Z, ZZ, ZZZ
The timezone in [+-]HHMM and [+-]HH:MM, and named form, respectively.
.TP
.B a, A
Lower and uppercase 'am' and 'pm' specifiers, respectively.
.TP
.B [...]
Quoted text, copied directly to the output.
.TP
.B _
When formatting, this inserts padding into the date format.
The padded width of a field is the sum of format and specifier
characters combined. When
For example,
.I __h
will format to a width of 3. When parsing, this acts as whitespace.
.TP
.B ?
When parsing, this makes the following argument match fuzzily.
Fuzzy matching means that all formats are tried, from most to least specific.
For example,
.I ?M
will match
.IR January ,
.IR Jan ,
.IR 01 ,
and
.IR 1 ,
in that order of preference.
.TP
.B ~
When parsing a date, this slackens range enforcement, accepting
out of range values such as January
.IR 32 ,
which would get normalized to February 1st.
.PP
Any characters not specified above are copied directly to output,
without modification.
.PP
If the format argument is nil, it makes an
attempt to parse common human readable date formats. These
formats include ISO-8601, RFC3339 and RFC2822 dates.
.
.PP
Tmfmt produces a format description structure suitable for passing
to
.IR fmtprint (2) .
If fmt is nil, we default to the format used in
.IR ctime (2).
The format of the format string is identical to
.IR tmparse.
.PP
When parsing, any amount of whitespace is treated as a single token.
All string matches are case insensitive, and zero padding is optional.
.PP
Tmnorm takes a manually adjusted Tm structure, and normalizes it,
returning the absolute timestamp that the date represents.
Normalizing recomputes the
.I year, mon, mday, hr, min, sec
and
.I tzoff
fields.
If
.I tz
is non-nil, then
.I tzoff
will be recomputed, taking into account daylight savings
for the absolute time.
The values not used in the computation are recomputed for
the resulting absolute time.
All out of range values are wrapped.
For example, December 32 will roll over to Jan 1 of the
following year.
.PP
Tmfmtinstall installs a time format specifier %τ. The time
format behaves as in tmfmt
.SH EXAMPLES
.PP
All examples assume tmfmtinstall has been called.
.PP
Get the current date in the local timezone, UTC, and
US_Pacific time. Print it using the default format.
.IP
.EX
Tm t;
Tzone *zl, *zp;
if((zl = tzload("local") == nil)
sysfatal("load zone: %r");
if((zp = tzload("US_Pacific") == nil)
sysfatal("load zone: %r");
print("local: %τ\\n", tmfmt(tmnow(&t, zl), nil));
print("gmt: %τ\\n", tmfmt(tmnow(&t, nil), nil));
print("eastern: %τ\\n", tmfmt(tmnow(&t, zp), nil));
.EE
.PP
Compare if two times are the same, regardless of timezone.
Done with full, strict error checking.
.IP
.EX
Tm a, b;
if(tmparse(&a, nil, "Tue Dec 10 12:36:00 PST 2019", &e) == nil)
sysfatal("failed to parse: %r");
if(*e != '\0')
sysfatal("trailing junk %s", e);
if(tmparse(&b, nil, "Tue Dec 10 15:36:00 EST 2019", &e) == nil)
sysfata("failed to parse: %r");
if(*e != '\0')
sysfatal("trailing junk %s", e);
if(tmnorm(a) == tmnorm(b) && a.nsec == b.nsec)
print("same\\n");
else
print("different\\n");
.EE
.PP
Convert from one timezone to another.
.IP
.EX
Tm here, there;
Tzone *zl, *zp;
if((zl = tzload("local")) == nil)
sysfatal("load zone: %r");
if((zp = tzload("US_Pacific")) == nil)
sysfatal("load zone: %r");
if(tmnow(&here, zl) == nil)
sysfatal("get time: %r");
if(tmtime(&there, tmnorm(&tm), zp) == nil)
sysfatal("shift time: %r");
.EE
.PP
Add a day. Because cross daylight savings, only 23 hours are added.
.EX
Tm t;
char *date = "Sun Nov 2 13:11:11 PST 2019";
if(tmparse(&t, "W MMM D hh:mm:ss z YYYY, date, &e) == nil)
print("failed top parse");
tm.day++;
tmnorm(&t);
print("%τ", &t); /* Mon Nov 3 13:11:11 PST 2019 */
.EE
.SH BUGS
.PP
There is no way to format specifier for subsecond precision.
.PP
The timezone information that we ship is out of date.
.PP
The Plan 9 timezone format has no way to express leap seconds.
.PP
We provide no way to manipulate timezones.

View file

@ -1,301 +1,39 @@
/*
* This routine converts time as follows.
* The epoch is 0000 Jan 1 1970 GMT.
* The argument time is in seconds since then.
* The localtime(t) entry returns a pointer to an array
* containing
*
* seconds (0-59)
* minutes (0-59)
* hours (0-23)
* day of month (1-31)
* month (0-11)
* year-1970
* weekday (0-6, Sun is 0)
* day of the year
* daylight savings flag
*
* The routine gets the daylight savings time from the environment.
*
* asctime(tvec))
* where tvec is produced by localtime
* returns a ptr to a character string
* that has the ascii time in the form
*
* \\
* Thu Jan 01 00:00:00 GMT 1970n0
* 012345678901234567890123456789
* 0 1 2
*
* ctime(t) just calls localtime, then asctime.
*/
#include <u.h> #include <u.h>
#include <libc.h> #include <libc.h>
static char dmsize[12] =
{
31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
};
/*
* The following table is used for 1974 and 1975 and
* gives the day number of the first day after the Sunday of the
* change.
*/
static int dysize(int);
static void ct_numb(char*, int);
#define TZSIZE 150
static void readtimezone(void);
static int rd_name(char**, char*);
static int rd_long(char**, long*);
static
struct
{
char stname[4];
char dlname[4];
long stdiff;
long dldiff;
long dlpairs[TZSIZE];
} timezone;
char*
ctime(long t)
{
return asctime(localtime(t));
}
Tm* Tm*
localtime(long tim) localtime(long tim)
{ {
Tm *ct; static Tm tm;
long t, *p; Tzone *tz;
int dlflag;
if(timezone.stname[0] == 0) /*
readtimezone(); * We have no way to report errors,
t = tim + timezone.stdiff; * so we just ignore them here.
dlflag = 0; */
for(p = timezone.dlpairs; *p; p += 2) tz = tzload("local");
if(t >= p[0]) tmtime(&tm, tim, tz);
if(t < p[1]) { return &tm;
t = tim + timezone.dldiff;
dlflag++;
break;
}
ct = gmtime(t);
if(dlflag){
strcpy(ct->zone, timezone.dlname);
ct->tzoff = timezone.dldiff;
} else {
strcpy(ct->zone, timezone.stname);
ct->tzoff = timezone.stdiff;
}
return ct;
} }
Tm* Tm*
gmtime(long tim) gmtime(long abs)
{ {
int d0, d1; static Tm tm;
long hms, day; return tmtime(&tm, abs, nil);
static Tm xtime;
/*
* break initial number into days
*/
hms = tim % 86400L;
day = tim / 86400L;
if(hms < 0) {
hms += 86400L;
day -= 1;
}
/*
* generate hours:minutes:seconds
*/
xtime.sec = hms % 60;
d1 = hms / 60;
xtime.min = d1 % 60;
d1 /= 60;
xtime.hour = d1;
/*
* day is the day number.
* generate day of the week.
* The addend is 4 mod 7 (1/1/1970 was Thursday)
*/
xtime.wday = (day + 7340036L) % 7;
/*
* year number
*/
if(day >= 0)
for(d1 = 1970; day >= dysize(d1); d1++)
day -= dysize(d1);
else
for (d1 = 1970; day < 0; d1--)
day += dysize(d1-1);
xtime.year = d1-1900;
xtime.yday = d0 = day;
/*
* generate month
*/
if(dysize(d1) == 366)
dmsize[1] = 29;
for(d1 = 0; d0 >= dmsize[d1]; d1++)
d0 -= dmsize[d1];
dmsize[1] = 28;
xtime.mday = d0 + 1;
xtime.mon = d1;
strcpy(xtime.zone, "GMT");
return &xtime;
} }
char* char*
asctime(Tm *t) ctime(long abs)
{ {
char *ncp; Tzone *tz;
static char cbuf[30]; Tm tm;
strcpy(cbuf, "Thu Jan 01 00:00:00 GMT 1970\n"); /*
ncp = &"SunMonTueWedThuFriSat"[t->wday*3]; * We have no way to report errors,
cbuf[0] = *ncp++; * so we just ignore them here.
cbuf[1] = *ncp++; */
cbuf[2] = *ncp; tz = tzload("local");
ncp = &"JanFebMarAprMayJunJulAugSepOctNovDec"[t->mon*3]; tmtime(&tm, abs, tz);
cbuf[4] = *ncp++; return asctime(&tm);
cbuf[5] = *ncp++;
cbuf[6] = *ncp;
ct_numb(cbuf+8, t->mday);
ct_numb(cbuf+11, t->hour+100);
ct_numb(cbuf+14, t->min+100);
ct_numb(cbuf+17, t->sec+100);
ncp = t->zone;
cbuf[20] = *ncp++;
cbuf[21] = *ncp++;
cbuf[22] = *ncp;
ct_numb(cbuf+24, (t->year+1900) / 100 + 100);
ct_numb(cbuf+26, t->year+100);
return cbuf;
}
static
dysize(int y)
{
if(y%4 == 0 && (y%100 != 0 || y%400 == 0))
return 366;
return 365;
}
static
void
ct_numb(char *cp, int n)
{
cp[0] = ' ';
if(n >= 10)
cp[0] = (n/10)%10 + '0';
cp[1] = n%10 + '0';
}
static
void
readtimezone(void)
{
char buf[TZSIZE*11+30], *p;
int i;
memset(buf, 0, sizeof(buf));
i = open("/env/timezone", 0);
if(i < 0)
goto error;
if(read(i, buf, sizeof(buf)) >= sizeof(buf)){
close(i);
goto error;
}
close(i);
p = buf;
if(rd_name(&p, timezone.stname))
goto error;
if(rd_long(&p, &timezone.stdiff))
goto error;
if(rd_name(&p, timezone.dlname))
goto error;
if(rd_long(&p, &timezone.dldiff))
goto error;
for(i=0; i<TZSIZE; i++) {
if(rd_long(&p, &timezone.dlpairs[i]))
goto error;
if(timezone.dlpairs[i] == 0)
return;
}
error:
timezone.stdiff = 0;
strcpy(timezone.stname, "GMT");
timezone.dlpairs[0] = 0;
}
static
rd_name(char **f, char *p)
{
int c, i;
for(;;) {
c = *(*f)++;
if(c != ' ' && c != '\n')
break;
}
for(i=0; i<3; i++) {
if(c == ' ' || c == '\n')
return 1;
*p++ = c;
c = *(*f)++;
}
if(c != ' ' && c != '\n')
return 1;
*p = 0;
return 0;
}
static
rd_long(char **f, long *p)
{
int c, s;
long l;
s = 0;
for(;;) {
c = *(*f)++;
if(c == '-') {
s++;
continue;
}
if(c != ' ' && c != '\n')
break;
}
if(c == 0) {
*p = 0;
return 0;
}
l = 0;
for(;;) {
if(c == ' ' || c == '\n')
break;
if(c < '0' || c > '9')
return 1;
l = l*10 + c-'0';
c = *(*f)++;
}
if(s)
l = -l;
*p = l;
return 0;
} }

View file

@ -1,202 +1,11 @@
#include <u.h> #include <u.h>
#include <libc.h> #include <libc.h>
#define TZSIZE 150
static void readtimezone(void);
static int rd_name(char**, char*);
static int rd_long(char**, long*);
static
struct
{
char stname[4];
char dlname[4];
long stdiff;
long dldiff;
long dlpairs[TZSIZE];
} timezone;
#define SEC2MIN 60L
#define SEC2HOUR (60L*SEC2MIN)
#define SEC2DAY (24L*SEC2HOUR)
/*
* days per month plus days/year
*/
static int dmsize[] =
{
365, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
};
static int ldmsize[] =
{
366, 31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
};
/*
* return the days/month for the given year
*/
static int *
yrsize(int y)
{
if((y%4) == 0 && ((y%100) != 0 || (y%400) == 0))
return ldmsize;
else
return dmsize;
}
/*
* compute seconds since Jan 1 1970 GMT
* and convert to our timezone.
*/
long long
tm2sec(Tm *tm) tm2sec(Tm *tm)
{ {
long secs, *p; Tm tt;
int i, yday, year, *d2m;
if(strcmp(tm->zone, "GMT") != 0 && timezone.stname[0] == 0) tt = *tm;
readtimezone(); return tmnorm(&tt);
secs = 0;
/*
* seconds per year
*/
year = tm->year + 1900;
for(i = 1970; i < year; i++){
d2m = yrsize(i);
secs += d2m[0] * SEC2DAY;
}
/*
* if mday is set, use mon and mday to compute yday
*/
if(tm->mday){
yday = 0;
d2m = yrsize(year);
for(i=0; i<tm->mon; i++)
yday += d2m[i+1];
yday += tm->mday-1;
}else{
yday = tm->yday;
}
secs += yday * SEC2DAY;
/*
* hours, minutes, seconds
*/
secs += tm->hour * SEC2HOUR;
secs += tm->min * SEC2MIN;
secs += tm->sec;
/*
* Only handles zones mentioned in /env/timezone,
* but things get too ambiguous otherwise.
*/
if(strcmp(tm->zone, timezone.stname) == 0)
secs -= timezone.stdiff;
else if(strcmp(tm->zone, timezone.dlname) == 0)
secs -= timezone.dldiff;
else if(tm->zone[0] == 0){
secs -= timezone.dldiff;
for(p = timezone.dlpairs; *p; p += 2)
if(secs >= p[0] && secs < p[1])
break;
if(*p == 0){
secs += timezone.dldiff;
secs -= timezone.stdiff;
}
}
return secs;
}
static
void
readtimezone(void)
{
char buf[TZSIZE*11+30], *p;
int i;
memset(buf, 0, sizeof(buf));
i = open("/env/timezone", 0);
if(i < 0)
goto error;
if(read(i, buf, sizeof(buf)) >= sizeof(buf))
goto error;
close(i);
p = buf;
if(rd_name(&p, timezone.stname))
goto error;
if(rd_long(&p, &timezone.stdiff))
goto error;
if(rd_name(&p, timezone.dlname))
goto error;
if(rd_long(&p, &timezone.dldiff))
goto error;
for(i=0; i<TZSIZE; i++) {
if(rd_long(&p, &timezone.dlpairs[i]))
goto error;
if(timezone.dlpairs[i] == 0)
return;
}
error:
timezone.stdiff = 0;
strcpy(timezone.stname, "GMT");
timezone.dlpairs[0] = 0;
}
static int
rd_name(char **f, char *p)
{
int c, i;
for(;;) {
c = *(*f)++;
if(c != ' ' && c != '\n')
break;
}
for(i=0; i<3; i++) {
if(c == ' ' || c == '\n')
return 1;
*p++ = c;
c = *(*f)++;
}
if(c != ' ' && c != '\n')
return 1;
*p = 0;
return 0;
}
static int
rd_long(char **f, long *p)
{
int c, s;
long l;
s = 0;
for(;;) {
c = *(*f)++;
if(c == '-') {
s++;
continue;
}
if(c != ' ' && c != '\n')
break;
}
if(c == 0) {
*p = 0;
return 0;
}
l = 0;
for(;;) {
if(c == ' ' || c == '\n')
break;
if(c < '0' || c > '9')
return 1;
l = l*10 + c-'0';
c = *(*f)++;
}
if(s)
l = -l;
*p = l;
return 0;
} }

996
sys/src/libc/port/date.c Normal file
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@ -0,0 +1,996 @@
#include <u.h>
#include <libc.h>
typedef struct Tzabbrev Tzabbrev;
typedef struct Tzoffpair Tzoffpair;
#define Ctimefmt "WW MMM _D hh:mm:ss ZZZ YYYY"
#define P(pad, w) ((pad) < (w) ? 0 : pad - w)
enum {
Tzsize = 150,
Nsec = 1000*1000*1000,
Usec = 1000*1000,
Msec = 1000,
Daysec = (vlong)24*3600,
Days400y = 365*400 + 4*25 - 3,
Days4y = 365*4 + 1,
};
enum {
Cend,
Cspace,
Cnum,
Cletter,
Cpunct,
};
struct Tzone {
char tzname[32];
char stname[16];
char dlname[16];
long stdiff;
long dldiff;
long dlpairs[150];
};
static QLock zlock;
static int nzones;
static Tzone **zones;
static int mdays[] = {
31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
};
static char *wday[] = {
"Sunday","Monday","Tuesday",
"Wednesday","Thursday","Friday",
"Saturday", nil,
};
static char *month[] = {
"January", "February", "March",
"April", "May", "June", "July",
"August", "September", "October",
"November", "December", nil
};
struct Tzabbrev {
char *abbr;
char *name;
};
struct Tzoffpair {
char *abbr;
int off;
};
#define isalpha(c)\
(((c)|0x60) >= 'a' && ((c)|0x60) <= 'z')
/* Obsolete time zone names. Hardcoded to match RFC5322 */
static Tzabbrev tzabbrev[] = {
{"UT", "GMT"}, {"GMT", "GMT"}, {"UTC", "GMT"},
{"EST", "US_Eastern"}, {"EDT", "US_Eastern"},
{"CST", "US_Central"}, {"CDT", "US_Central"},
{"MST", "US_Mountain"}, {"MDT", "US_Mountain"},
{"PST", "US_Pacific"}, {"PDT", "US_Pacific"},
{nil},
};
/* Military timezone names */
static Tzoffpair milabbrev[] = {
{"A", -1*3600}, {"B", -2*3600}, {"C", -3*3600},
{"D", -4*3600}, {"E", -5*3600}, {"F", -6*3600},
{"G", -7*3600}, {"H", -8*3600}, {"I", -9*3600},
{"K", -10*3600}, {"L", -11*3600}, {"M", -12*3600},
{"N", +1*3600}, {"O", +2*3600}, {"P", +3*3600},
{"Q", +4*3600}, {"R", +5*3600}, {"S", +6*3600},
{"T", +7*3600}, {"U", +8*3600}, {"V", +9*3600},
{"W", +10*3600}, {"X", +11*3600}, {"Y", +12*3600},
{"Z", 0}, {nil, 0}
};
static vlong
mod(vlong a, vlong b)
{
vlong r;
r = a % b;
if(r < 0)
r += b;
return r;
}
static int
isleap(int y)
{
return y % 4 == 0 && (y % 100 != 0 || y % 400 == 0);
}
static int
rdname(char **f, char *p, int n)
{
char *s, *e;
for(s = *f; *s; s++)
if(*s != ' ' && *s != '\t' && *s != '\n')
break;
e = s + n;
for(; *s && s != e; s++) {
if(*s == ' ' || *s == '\t' || *s == '\n')
break;
*p++ = *s;
}
*p = 0;
if(n - (e - s) < 3 || *s != ' ' && *s != '\t' && *s != '\n'){
werrstr("truncated name");
return -1;
}
*f = s;
return 0;
}
static int
rdlong(char **f, long *p)
{
int c, s;
long l;
s = 0;
while((c = *(*f)++) != 0){
if(c == '-')
s++;
else if(c != ' ' && c != '\n')
break;
}
if(c == 0) {
*p = 0;
return 0;
}
l = 0;
for(;;) {
if(c == ' ' || c == '\n')
break;
if(c < '0' || c > '9'){
werrstr("non-number %c in name", c);
return -1;
}
l = l*10 + c-'0';
c = *(*f)++;
}
if(s)
l = -l;
*p = l;
return 0;
}
static int
loadzone(Tzone *tz, char *name)
{
char buf[Tzsize*11+30], path[128], *p;
int i, f, r;
memset(tz, 0, sizeof(Tzone));
if(strcmp(name, "local") == 0)
snprint(path, sizeof(path), "/env/timezone");
else
snprint(path, sizeof(path), "/adm/timezone/%s", name);
memset(buf, 0, sizeof(buf));
if((f = open(path, 0)) == -1)
return -1;
r = read(f, buf, sizeof(buf));
close(f);
if(r == sizeof(buf) || r == -1)
return -1;
buf[r] = 0;
p = buf;
if(rdname(&p, tz->stname, sizeof(tz->stname)) == -1)
return -1;
if(rdlong(&p, &tz->stdiff) == -1)
return -1;
if(rdname(&p, tz->dlname, sizeof(tz->dlname)) == -1)
return -1;
if(rdlong(&p, &tz->dldiff) == -1)
return -1;
for(i=0; i < Tzsize; i++) {
if(rdlong(&p, &tz->dlpairs[i]) == -1){
werrstr("invalid transition time");
return -1;
}
if(tz->dlpairs[i] == 0)
return 0;
}
werrstr("invalid timezone %s", name);
return -1;
}
Tzone*
tzload(char *tzname)
{
Tzone *tz, **newzones;
int i;
if(tzname == nil)
tzname = "GMT";
qlock(&zlock);
for(i = 0; i < nzones; i++){
tz = zones[i];
if(strcmp(tz->stname, tzname) == 0)
goto found;
if(strcmp(tz->dlname, tzname) == 0)
goto found;
if(strcmp(tz->tzname, tzname) == 0)
goto found;
}
tz = malloc(sizeof(Tzone));
if(tz == nil)
goto error;
newzones = realloc(zones, (nzones + 1) * sizeof(Tzone*));
if(newzones == nil)
goto error;
if(loadzone(tz, tzname) != 0)
goto error;
if(snprint(tz->tzname, sizeof(tz->tzname), tzname) >= sizeof(tz->tzname)){
werrstr("timezone name too long");
return nil;
}
zones = newzones;
zones[nzones] = tz;
nzones++;
found:
qunlock(&zlock);
return tz;
error:
free(tz);
qunlock(&zlock);
return nil;
}
static void
tzoffset(Tzone *tz, vlong abs, Tm *tm)
{
long dl, *p;
dl = 0;
if(tz == nil){
snprint(tm->zone, sizeof(tm->zone), "GMT");
tm->tzoff = 0;
return;
}
for(p = tz->dlpairs; *p; p += 2)
if(abs > p[0] && abs <= p[1]){
dl = 1;
break;
}
if(dl){
snprint(tm->zone, sizeof(tm->zone), tz->dlname);
tm->tzoff = tz->dldiff;
}else{
snprint(tm->zone, sizeof(tm->zone), tz->stname);
tm->tzoff = tz->stdiff;
}
}
static Tm*
tmfill(Tm *tm, vlong abs, vlong nsec)
{
vlong zrel, j, y, m, d, t, e;
int i;
zrel = abs + tm->tzoff;
t = zrel % Daysec;
e = zrel / Daysec;
if(t < 0){
t += Daysec;
e -= 1;
}
t += nsec/Nsec;
tm->sec = mod(t, 60);
t /= 60;
tm->min = mod(t, 60);
t /= 60;
tm->hour = mod(t, 24);
tm->wday = mod((e + 4), 7);
/*
* Split up year, month, day.
*
* Implemented according to "Algorithm 199,
* conversions between calendar date and
* Julian day number", Robert G. Tantzen,
* Air Force Missile Development
* Center, Holloman AFB, New Mex.
*
* Lots of magic.
*/
j = (zrel + 2440588 * Daysec) / (Daysec) - 1721119;
y = (4 * j - 1) / Days400y;
j = 4 * j - 1 - Days400y * y;
d = j / 4;
j = (4 * d + 3) / Days4y;
d = 4 * d + 3 - Days4y * j;
d = (d + 4) / 4 ;
m = (5 * d - 3) / 153;
d = 5 * d - 3 - 153 * m;
d = (d + 5) / 5;
y = 100 * y + j;
if(m < 10)
m += 3;
else{
m -= 9;
y++;
}
/* there's no year 0 */
if(y <= 0)
y--;
/* and if j negative, the day and month are also negative */
if(m < 0)
m += 12;
if(d < 0)
d += mdays[m - 1];
tm->yday = d;
for(i = 0; i < m - 1; i++)
tm->yday += mdays[i];
if(m > 1 && isleap(y))
tm->yday++;
tm->year = y - 1900;
tm->mon = m - 1;
tm->mday = d;
tm->nsec = mod(nsec, Nsec);
return tm;
}
Tm*
tmtime(Tm *tm, vlong abs, Tzone *tz)
{
return tmtimens(tm, abs, 0, tz);
}
Tm*
tmtimens(Tm *tm, vlong abs, int ns, Tzone *tz)
{
tm->tz = tz;
tzoffset(tz, abs, tm);
return tmfill(tm, abs, ns);
}
Tm*
tmnow(Tm *tm, Tzone *tz)
{
vlong ns;
ns = nsec();
return tmtimens(tm, nsec()/Nsec, mod(ns, Nsec), tz);
}
vlong
tmnorm(Tm *tm)
{
vlong c, yadj, j, abs, y, m, d;
if(tm->mon > 1){
m = tm->mon - 2;
y = tm->year + 1900;
}else{
m = tm->mon + 10;
y = tm->year + 1899;
}
d = tm->mday;
c = y / 100;
yadj = y - 100 * c;
j = (c * Days400y / 4 +
Days4y * yadj / 4 +
(153 * m + 2)/5 + d -
719469);
abs = j * Daysec;
abs += tm->hour * 3600;
abs += tm->min * 60;
abs += tm->sec;
if(tm->tz){
tzoffset(tm->tz, abs - tm->tzoff, tm);
tzoffset(tm->tz, abs - tm->tzoff, tm);
}
abs -= tm->tzoff;
tmfill(tm, abs, tm->nsec);
return abs;
}
static int
τconv(Fmt *f)
{
int depth, n, v, w, h, m, c0, sgn, pad, off;
char *p, *am;
Tmfmt tf;
Tm *tm;
n = 0;
tf = va_arg(f->args, Tmfmt);
tm = tf.tm;
p = tf.fmt;
if(p == nil)
p = Ctimefmt;
while(*p){
w = 1;
pad = 0;
while(*p == '_'){
pad++;
p++;
}
c0 = *p++;
while(c0 && *p == c0){
w++;
p++;
}
pad += w;
switch(c0){
case 0:
break;
case 'Y':
switch(w){
case 1: n += fmtprint(f, "%*d", pad, tm->year + 1900); break;
case 2: n += fmtprint(f, "%*d", pad, tm->year % 100); break;
case 4: n += fmtprint(f, "%*d", pad, tm->year + 1900); break;
default: goto badfmt;
}
break;
case 'M':
switch(w){
case 1: n += fmtprint(f, "%*d", pad, tm->mon + 1); break;
case 2: n += fmtprint(f, "%*s%02d", pad-2, "", tm->mon + 1); break;
case 3: n += fmtprint(f, "%*.3s", pad, month[tm->mon]); break;
case 4: n += fmtprint(f, "%*s", pad, month[tm->mon]); break;
default: goto badfmt;
}
break;
case 'D':
switch(w){
case 1: n += fmtprint(f, "%*d", pad, tm->mday); break;
case 2: n += fmtprint(f, "%*s%02d", pad-2, "", tm->mday); break;
default: goto badfmt;
}
break;
case 'W':
switch(w){
case 1: n += fmtprint(f, "%*d", pad, tm->wday + 1); break;
case 2: n += fmtprint(f, "%*.3s", pad, wday[tm->wday]); break;
case 3: n += fmtprint(f, "%*s", pad, wday[tm->wday]); break;
default: goto badfmt;
}
break;
case 'H':
switch(w){
case 1: n += fmtprint(f, "%*d", pad, tm->hour % 12); break;
case 2: n += fmtprint(f, "%*s%02d", pad-2, "", tm->hour % 12); break;
default: goto badfmt;
}
break;
case 'h':
switch(w){
case 1: n += fmtprint(f, "%*d", pad, tm->hour); break;
case 2: n += fmtprint(f, "%*s%02d", pad-2, "", tm->hour); break;
default: goto badfmt;
}
break;
case 'm':
switch(w){
case 1: n += fmtprint(f, "%*d", pad, tm->min); break;
case 2: n += fmtprint(f, "%*s%02d", pad-2, "", tm->min); break;
default: goto badfmt;
}
break;
case 's':
switch(w){
case 1: n += fmtprint(f, "%*d", pad, tm->sec); break;
case 2: n += fmtprint(f, "%*s%02d", pad-2, "", tm->sec); break;
default: goto badfmt;
}
break;
case 't':
v = tm->nsec / (1000*1000);
switch(w){
case 1: n += fmtprint(f, "%*d", pad, v % 1000); break;
case 2:
case 3: n += fmtprint(f, "%*s%03d", P(pad, 3), "", v % 1000); break;
default: goto badfmt;
}
break;
case 'u':
v = tm->nsec / 1000;
switch(w){
case 1: n += fmtprint(f, "%*d", pad, v % 1000); break;
case 2: n += fmtprint(f, "%*s%03d", P(pad, 3), "", v % 1000); break;
case 3: n += fmtprint(f, "%*d", P(pad, 6), v); break;
case 4: n += fmtprint(f, "%*s%06d", P(pad, 6), "", v); break;
default: goto badfmt;
}
break;
case 'n':
v = tm->nsec;
switch(w){
case 1: n += fmtprint(f, "%*d", pad, v%1000); break;
case 2: n += fmtprint(f, "%*s%03d", P(pad, 3), "", v % 1000); break;
case 3: n += fmtprint(f, "%*d", pad , v%(1000*1000)); break;
case 4: n += fmtprint(f, "%*s%06d", P(pad, 6), "", v%(1000000)); break;
case 5: n += fmtprint(f, "%*d", pad, v); break;
case 6: n += fmtprint(f, "%*s%09d", P(pad, 9), "", v); break;
default: goto badfmt;
}
break;
case 'z':
if(w != 1)
goto badfmt;
case 'Z':
sgn = (tm->tzoff < 0) ? '-' : '+';
off = (tm->tzoff < 0) ? -tm->tzoff : tm->tzoff;
h = off/3600;
m = (off/60)%60;
if(w < 3 && pad < 5)
pad = 5;
switch(w){
case 1: n += fmtprint(f, "%*s%c%02d%02d", pad-5, "", sgn, h, m); break;
case 2: n += fmtprint(f, "%*s%c%02d:%02d", pad-5, "", sgn, h, m); break;
case 3: n += fmtprint(f, "%*s", pad, tm->zone); break;
}
break;
case 'A':
case 'a':
if(w != 1)
goto badfmt;
if(c0 == 'a')
am = (tm->hour < 12) ? "am" : "pm";
else
am = (tm->hour < 12) ? "AM" : "PM";
n += fmtprint(f, "%*s", pad, am);
break;
case '[':
depth = 1;
while(*p){
if(*p == '[')
depth++;
if(*p == ']')
depth--;
if(*p == '\\')
p++;
if(depth == 0)
break;
fmtrune(f, *p++);
}
if(*p++ != ']')
goto badfmt;
break;
default:
while(w-- > 0)
n += fmtrune(f, c0);
break;
}
}
return n;
badfmt:
werrstr("garbled format %s", tf.fmt);
return -1;
}
static int
getnum(char **ps, int maxw, int *ok)
{
char *s, *e;
int n;
n = 0;
e = *ps + maxw;
for(s = *ps; s != e && *s >= '0' && *s <= '9'; s++){
n *= 10;
n += *s - '0';
}
*ok = s != *ps;
*ps = s;
return n;
}
static int
lookup(char **s, char **tab, int len, int *ok)
{
int nc, i;
*ok = 0;
for(i = 0; *tab; tab++){
nc = (len != -1) ? len : strlen(*tab);
if(cistrncmp(*s, *tab, nc) == 0){
*s += nc;
*ok = 1;
return i;
}
i++;
}
*ok = 0;
return -1;
}
Tm*
tmparse(Tm *tm, char *fmt, char *str, Tzone *tz, char **ep)
{
int depth, n, w, c0, zs, z0, z1, md, ampm, zoned, sloppy, tzo, ok;
vlong abs;
char *s, *p, *q;
Tzone *zparsed;
Tzabbrev *a;
Tzoffpair *m;
p = fmt;
s = str;
tzo = 0;
ampm = -1;
zoned = 0;
zparsed = nil;
sloppy = 0;
/* Default all fields */
tmtime(tm, 0, nil);
if(*p == '~'){
sloppy = 1;
p++;
}
while(*p){
w = 1;
c0 = *p++;
if(c0 == '?'){
w = -1;
c0 = *p++;
}
while(*p == c0){
if(w != -1) w++;
p++;
}
ok = 1;
switch(c0){
case 'Y':
switch(w){
case -1:
tm->year = getnum(&s, 4, &ok);
if(tm->year > 100) tm->year -= 1900;
break;
case 1: tm->year = getnum(&s, 4, &ok) - 1900; break;
case 2: tm->year = getnum(&s, 2, &ok); break;
case 3:
case 4: tm->year = getnum(&s, 4, &ok) - 1900; break;
default: goto badfmt;
}
break;
case 'M':
switch(w){
case -1:
tm->mon = getnum(&s, 2, &ok) - 1;
if(!ok) tm->mon = lookup(&s, month, -1, &ok);
if(!ok) tm->mon = lookup(&s, month, 3, &ok);
break;
case 1:
case 2: tm->mon = getnum(&s, 2, &ok) - 1; break;
case 3: tm->mon = lookup(&s, month, 3, &ok); break;
case 4: tm->mon = lookup(&s, month, -1, &ok); break;
default: goto badfmt;
}
break;
case 'D':
switch(w){
case -1:
case 1:
case 2: tm->mday = getnum(&s, 2, &ok); break;
default: goto badfmt;
}
break;
case 'W':
switch(w){
case -1:
tm->wday = lookup(&s, wday, -1, &ok);
if(!ok) tm->wday = lookup(&s, wday, 3, &ok);
if(!ok) tm->wday = getnum(&s, 1, &ok) - 1;
break;
case 1: tm->wday = getnum(&s, 1, &ok) - 1; break;
case 2: tm->wday = lookup(&s, wday, 3, &ok); break;
case 3: tm->wday = lookup(&s, wday, -1, &ok); break;
default: goto badfmt;
}
break;
case 'h':
switch(w){
case -1:
case 1:
case 2: tm->hour = getnum(&s, 2, &ok); break;
default: goto badfmt;
}
break;
case 'm':
switch(w){
case -1:
case 1:
case 2: tm->min = getnum(&s, 2, &ok); break;
default: goto badfmt;
}
break;
case 's':
switch(w){
case -1:
case 1:
case 2: tm->sec = getnum(&s, 2, &ok); break;
default: goto badfmt;
}
break;
case 't':
switch(w){
case -1:
case 1:
case 2:
case 3: tm->nsec += getnum(&s, 3, &ok)*1000000; break;
}
break;
case 'u':
switch(w){
case -1:
case 1:
case 2: tm->nsec += getnum(&s, 3, &ok)*1000; break;
case 3:
case 4: tm->nsec += getnum(&s, 6, &ok)*1000; break;
}
break;
case 'n':
switch(w){
case 1:
case 2: tm->nsec += getnum(&s, 3, &ok); break;
case 3:
case 4: tm->nsec += getnum(&s, 6, &ok); break;
case -1:
case 5:
case 6: tm->nsec += getnum(&s, 9, &ok); break;
}
break;
case 'z':
if(w != 1)
goto badfmt;
case 'Z':
zs = 0;
zoned = 1;
switch(*s++){
case '+': zs = 1; break;
case '-': zs = -1; break;
default: s--; break;
}
q = s;
switch(w){
case -1:
case 3:
for(a = tzabbrev; a->abbr; a++){
n = strlen(a->abbr);
if(cistrncmp(s, a->abbr, n) == 0 && !isalpha(s[n]))
break;
}
if(a->abbr != nil){
s += strlen(a->abbr);
zparsed = tzload(a->name);
if(zparsed == nil){
werrstr("unloadable zone %s (%s)", a->abbr, a->name);
if(w != -1)
return nil;
}
goto Zoneparsed;
}
for(m = milabbrev; m->abbr != nil; m++){
n = strlen(m->abbr);
if(cistrncmp(s, m->abbr, n) == 0 && !isalpha(s[n]))
break;
}
if(m->abbr != nil){
snprint(tm->zone, sizeof(tm->zone), "%s", m->abbr);
tzo = m->off;
goto Zoneparsed;
}
if(w != -1)
break;
/* fall through */
case 1:
/* offset: [+-]hhmm */
z0 = getnum(&s, 4, &ok);
if(s - q == 4){
z1 = z0 % 100;
if(z0/100 > 13 || z1 >= 60)
goto baddate;
tzo = zs*(3600*(z0/100) + 60*z1);
snprint(tm->zone, sizeof(tm->zone), "%c%02d%02d", zs<0?'-':'+', z0/100, z1);
goto Zoneparsed;
}
if(w != -1)
goto baddate;
/* fall through */
case 2:
s = q;
/* offset: [+-]hh:mm */
z0 = getnum(&s, 2, &ok);
if(*s++ != ':')
break;
z1 = getnum(&s, 2, &ok);
if(z1 > 60)
break;
tzo = zs*(3600*z0 + 60*z1);
snprint(tm->zone, sizeof(tm->zone), "%c%d02:%02d", zs<0?'-':'+', z0, z1);
goto Zoneparsed;
}
if(w != -1)
goto baddate;
/*
* Final fuzzy fallback: If we have what looks like an
* unknown timezone abbreviation, keep the zone name,
* but give it a timezone offset of 0. This allows us
* to avoid rejecting zones outside of RFC5322.
*/
for(s = q; *s; s++)
if(!isalpha(*s))
break;
if(s - q >= 3 && !isalpha(*s)){
strncpy(tm->zone, q, s - q);
tzo = 0;
ok = 1;
goto Zoneparsed;
}
goto baddate;
Zoneparsed:
break;
case 'A':
case 'a':
if(cistrncmp(s, "am", 2) == 0)
ampm = 0;
else if(cistrncmp(s, "pm", 2) == 0)
ampm = 1;
else
goto baddate;
s += 2;
break;
case '[':
depth = 1;
while(*p){
if(*p == '[')
depth++;
if(*p == ']')
depth--;
if(*p == '\\')
p++;
if(depth == 0)
break;
if(*s == 0)
goto baddate;
if(*s++ != *p++)
goto baddate;
}
if(*p != ']')
goto badfmt;
p++;
break;
case '_':
case ',':
case ' ':
if(*s != ' ' && *s != '\t' && *s != ',' && *s != '\n' && *s != '\0')
goto baddate;
p += strspn(p, " ,_\t\n");
s += strspn(s, " ,\t\n");
break;
default:
if(*s == 0)
goto baddate;
if(*s++ != c0)
goto baddate;
break;
}
if(!ok)
goto baddate;
}
if(*p != '\0')
goto baddate;
if(ep != nil)
*ep = s;
if(!sloppy && ampm != -1 && (tm->hour < 1 || tm->hour > 12))
goto baddate;
if(ampm == 0 && tm->hour == 12)
tm->hour = 0;
else if(ampm == 1 && tm->hour < 12)
tm->hour += 12;
/*
* If we're allowing sloppy date ranges,
* we'll normalize out of range values.
*/
if(!sloppy){
if(tm->yday < 0 || tm->yday > 365 + isleap(tm->year + 1900))
goto baddate;
if(tm->wday < 0 || tm->wday > 6)
goto baddate;
if(tm->mon < 0 || tm->mon > 11)
goto baddate;
md = mdays[tm->mon];
if(tm->mon == 1 && isleap(tm->year + 1900))
md++;
if(tm->mday < 0 || tm->mday > md)
goto baddate;
if(tm->hour < 0 || tm->hour > 24)
goto baddate;
if(tm->min < 0 || tm->min > 59)
goto baddate;
if(tm->sec < 0 || tm->sec > 60)
goto baddate;
if(tm->nsec < 0 || tm->nsec > Nsec)
goto baddate;
if(tm->wday < 0 || tm->wday > 6)
goto baddate;
}
/*
* Normalizing gives us the local time,
* but because we havnen't applied the
* timezone, we think we're GMT. So, we
* need to shift backwards. Then, we move
* the "GMT that was local" back to local
* time.
*/
abs = tmnorm(tm);
tm->tzoff = tzo;
if(!zoned)
tzoffset(tz, abs, tm);
else if(zparsed != nil){
tzoffset(zparsed, abs, tm);
tzoffset(zparsed, abs + tm->tzoff, tm);
}
abs -= tm->tzoff;
if(tz != nil || !zoned)
tmtimens(tm, abs, tm->nsec, tz);
return tm;
baddate:
werrstr("invalid date %s", str);
return nil;
badfmt:
werrstr("garbled format %s near '%s'", fmt, p);
return nil;
}
Tmfmt
tmfmt(Tm *d, char *fmt)
{
return (Tmfmt){fmt, d};
}
void
tmfmtinstall(void)
{
fmtinstall(L'τ', τconv);
}
/* These legacy functions need access to τconv */
static char*
dotmfmt(Fmt *f, ...)
{
static char buf[30];
va_list ap;
va_start(ap, f);
f->runes = 0;
f->start = buf;
f->to = buf;
f->stop = buf + sizeof(buf) - 1;
f->flush = nil;
f->farg = nil;
f->nfmt = 0;
f->args = ap;
τconv(f);
va_end(ap);
buf[sizeof(buf) - 1] = 0;
return buf;
}
char*
asctime(Tm* tm)
{
Tmfmt tf;
Fmt f;
tf = tmfmt(tm, "WW MMM _D hh:mm:ss ZZZ YYYY\n");
return dotmfmt(&f, tf);
}

View file

@ -20,6 +20,7 @@ CFILES=\
cleanname.c\ cleanname.c\
crypt.c\ crypt.c\
ctype.c\ ctype.c\
date.c\
encodefmt.c\ encodefmt.c\
execl.c\ execl.c\
exits.c\ exits.c\