date.c revision 7c2fbfb345896881c631598ee3852ce9ce33fb07
/***********************************************************************
* *
* This software is part of the ast package *
* Copyright (c) 1992-2008 AT&T Intellectual Property *
* and is licensed under the *
* Common Public License, Version 1.0 *
* by AT&T Intellectual Property *
* *
* A copy of the License is available at *
* http://www.opensource.org/licenses/cpl1.0.txt *
* (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) *
* *
* Information and Software Systems Research *
* AT&T Research *
* Florham Park NJ *
* *
* Glenn Fowler <gsf@research.att.com> *
* David Korn <dgk@research.att.com> *
* *
***********************************************************************/
#pragma prototyped
/*
* Glenn Fowler
* AT&T Research
*
* date -- set/display date
*/
static const char usage[] =
"[-?\n@(#)$Id: date (AT&T Research) 2007-05-21 $\n]"
USAGE_LICENSE
"[+NAME?date - set/list/convert dates]"
"[+DESCRIPTION?\bdate\b sets the current date and time (with appropriate"
" privilege), lists the current date or file dates, or converts"
" dates.]"
"[+?Most common \adate\a forms are recognized, including those for"
" \bcrontab\b(1), \bls\b(1), \btouch\b(1), and the default"
" output from \bdate\b itself.]"
"[+?If the \adate\a operand consists of 4, 6, 8, 10 or 12 digits followed"
" by an optional \b.\b and two digits then it is interpreted as:"
" \aHHMM.SS\a, \addHHMM.SS\a, \ammddHHMM.SS\a, \ammddHHMMyy.SS\a or"
" \ayymmddHHMM.SS\a, or \ammddHHMMccyy.SS\a or \accyymmddHHMM.SS\a."
" Conflicting standards and practice allow a leading or trailing"
" 2 or 4 digit year for the 10 and 12 digit forms; the X/Open trailing"
" form is used to disambiguate (\btouch\b(1) uses the leading form.)"
" Avoid the 10 digit form to avoid confusion. The digit fields are:]{"
" [+cc?Century - 1, 19-20.]"
" [+yy?Year in century, 00-99.]"
" [+mm?Month, 01-12.]"
" [+dd?Day of month, 01-31.]"
" [+HH?Hour, 00-23.]"
" [+MM?Minute, 00-59.]"
" [+SS?Seconds, 00-60.]"
"}"
"[+?If more than one \adate\a operand is specified then:]{"
" [+1.?Each operand sets the reference date for the next"
" operand.]"
" [+2.?The date is listed for each operand.]"
" [+3.?The system date is not set.]"
"}"
"[a:access-time|atime?List file argument access times.]"
"[c:change-time|ctime?List file argument change times.]"
"[d:date?Use \adate\a as the current date and do not set the system"
" clock.]:[date]"
"[e:epoch?Output the date in seconds since the epoch."
" Equivalent to \b--format=%s\b.]"
"[E:elapsed?Interpret pairs of arguments as start and stop dates, sum the"
" differences between all pairs, and list the result as a"
" \bfmtelapsed\b(3) elapsed time on the standard output. If there are"
" an odd number of arguments then the last time argument is differenced"
" with the current time.]"
"[f:format?Output the date according to the \bstrftime\b(3) \aformat\a."
" For backwards compatibility, a first argument of the form"
" \b+\b\aformat\a is equivalent to \b-f\b format."
" \aformat\a is in \bprintf\b(3) style, where %\afield\a names"
" a fixed size field, zero padded if necessary,"
" and \\\ac\a and \\\annn\a sequences are as in C. Invalid"
" %\afield\a specifications and all other characters are copied"
" without change. \afield\a may be preceded by \b%-\b to turn off"
" padding or \b%_\b to pad with space, otherwise numeric fields"
" are padded with \b0\b and string fields are padded with space."
" \afield\a may also be preceded by \bE\b for alternate era"
" representation or \bO\b for alternate digit representation (if"
" supported by the current locale.) Finally, an integral \awidth\a"
" preceding \afield\a truncates the field to \awidth\a characters."
" The fields are:]:[format]{"
" [+%?% character]"
" [+a?abbreviated weekday name]"
" [+A?full weekday name]"
" [+b?abbreviated month name]"
" [+c?\bctime\b(3) style date without the trailing newline]"
" [+C?2-digit century]"
" [+d?day of month number]"
" [+D?date as \amm/dd/yy\a]"
" [+e?blank padded day of month number]"
" [+E?unpadded day of month number]"
" [+f?locale default override date format]"
" [+F?%ISO 8601:2000 standard date format; equivalent to Y-%m-%d]"
" [+g?\bls\b(1) \b-l\b recent date with \ahh:mm\a]"
" [+G?\bls\b(1) \b-l\b distant date with \ayyyy\a]"
" [+h?abbreviated month name]"
" [+H?24-hour clock hour]"
" [+i?international \bdate\b(1) date with time zone type name]"
" [+I?12-hour clock hour]"
" [+j?1-offset Julian date]"
" [+J?0-offset Julian date]"
" [+k?\bdate\b(1) style date]"
" [+K?all numeric date; equivalent to \b%Y-%m-%d+%H:%M:%S\b]"
" [+l?\bls\b(1) \b-l\b date; equivalent to \b%Q/%g/%G/\b]"
" [+L?locale default date format]"
" [+m?month number]"
" [+M?minutes]"
" [+n?newline character]"
" [+N?nanoseconds 000000000-999999999]"
" [+p?meridian (e.g., \bAM\b or \bPM\b)]"
" [+q?time zone type name (nation code)]"
" [+Q?\a<del>recent<del>distant<del>\a: \a<del>\a is a unique"
" delimter character; \arecent\a format for recent"
" dates, \adistant\a format otherwise]"
" [+r?12-hour time as \ahh:mm:ss meridian\a]"
" [+R?24-hour time as \ahh:mm\a]"
" [+s?number of seconds since the epoch; \a.prec\a preceding"
" \bs\b appends \aprec\a nanosecond digits, \b9\b if"
" \aprec\a is omitted]"
" [+S?seconds 00-60]"
" [+t?tab character]"
" [+T?24-hour time as \ahh:mm:ss\a]"
" [+u?weekday number 1(Monday)-7]"
" [+U?week number with Sunday as the first day]"
" [+V?ISO week number (i18n is \afun\a)]"
" [+w?weekday number 0(Sunday)-6]"
" [+W?week number with Monday as the first day]"
" [+x?locale date style that includes month, day and year]"
" [+X?locale time style that includes hours and minutes]"
" [+y?2-digit year (you'll be sorry)]"
" [+Y?4-digit year]"
" [+z?time zone \aSHHMM\a west of GMT offset where S is"
" \b+\b or \b-\b]"
" [+Z?time zone name]"
" [+=[=]][-+]]flag?set (default or +) or clear (-) \aflag\a"
" for the remainder of \aformat\a, or for the remainder"
" of the process if \b==\b is specified. \aflag\a may be:]{"
" [+l?enable leap second adjustments]"
" [+n?convert \b%S\b as \b%S.%N\b]"
" [+u?UTC time zone]"
" }"
" [+#?equivalent to %s]"
" [+??alternate?use \aalternate\a format if a default format"
" override has not been specified, e.g., \bls\b(1) uses"
" \"%?%l\"; export TM_OPTIONS=\"format='\aoverride\a'\""
" to override the default]"
"}"
"[i:incremental|adjust?Set the system time in incrementatl adjustments to"
" avoid complete time shift shock. Negative adjustments still maintain"
" monotonic increasing time. Not available on all systems.]"
"[L:last?List only the last time for multiple \adate\a operands.]"
"[l:leap-seconds?Include leap seconds in time calculations. Leap seconds"
" after the ast library release date are not accounted for.]"
"[m:modify-time|mtime?List file argument modify times.]"
"[n!:network?Set network time.]"
"[p:parse?Add \aformat\a to the list of \bstrptime\b(3) parse conversion"
" formats. \aformat\a follows the same conventions as the"
" \b--format\b option, with the addition of these format"
" fields:]:[format]{"
" [+|?If the format failed before this point then restart"
" the parse with the remaining format.]"
" [+&?Call the \btmdate\b(3) heuristic parser. This is"
" is the default when \b--parse\b is omitted.]"
"}"
"[s:show?Show the date without setting the system time.]"
"[u:utc|gmt|zulu?Output dates in \acoordinated universal time\a (UTC).]"
"[U:unelapsed?Interpret each argument as \bfmtelapsed\b(3) elapsed"
" time and list the \bstrelapsed\b(3) 1/\ascale\a seconds.]#[scale]"
"[z:list-zones?List the known time zone table and exit. The table columns"
" are: country code, standard zone name, savings time zone name,"
" minutes west of \bUTC\b, and savings time minutes offset. Blank"
" or empty entries are listed as \b-\b.]"
"\n"
"\n[ +format | date ... | file ... ]\n"
"\n"
"[+SEE ALSO?\bcrontab\b(1), \bls\b(1), \btouch\b(1), \bfmtelapsed\b(3),"
" \bstrftime\b(3), \bstrptime\b(3), \btm\b(3)]"
;
#include <cmd.h>
#include <ls.h>
#include <proc.h>
#include <tmx.h>
#include <times.h>
typedef struct Fmt
{
struct Fmt* next;
char* format;
} Fmt_t;
#ifndef ENOSYS
#define ENOSYS EINVAL
#endif
/*
* set the system clock
* the standards wimped out here
*/
static int
settime(void* context, const char* cmd, Time_t now, int adjust, int network)
{
char* s;
char** argv;
char* args[5];
char buf[128];
if (!adjust && !network)
return tmxsettime(now);
argv = args;
s = "/usr/bin/date";
if (!streq(cmd, s) && (!eaccess(s, X_OK) || !eaccess(s+=4, X_OK)))
{
*argv++ = s;
if (streq(astconf("UNIVERSE", NiL, NiL), "att"))
{
tmxfmt(buf, sizeof(buf), "%m%d%H" "%M%Y.%S", now);
if (adjust)
*argv++ = "-a";
}
else
{
tmxfmt(buf, sizeof(buf), "%Y%m%d%H" "%M.%S", now);
if (network)
*argv++ = "-n";
if (tm_info.flags & TM_UTC)
*argv++ = "-u";
}
*argv++ = buf;
*argv = 0;
if (!sh_run(context, argv - args, args))
return 0;
}
return -1;
}
/*
* convert s to Time_t with error checking
*/
static Time_t
convert(register Fmt_t* f, char* s, Time_t now)
{
char* t;
char* u;
do
{
now = tmxscan(s, &t, f->format, &u, now, 0);
if (!*t && (!f->format || !*u))
break;
} while (f = f->next);
if (!f || *t)
error(3, "%s: invalid date specification", f ? t : s);
return now;
}
int
b_date(int argc, register char** argv, void* context)
{
register int n;
register char* s;
register Fmt_t* f;
char* t;
unsigned long u;
Time_t now;
Time_t ts;
Time_t te;
Time_t e;
char buf[128];
Fmt_t* fmts;
Fmt_t fmt;
struct stat st;
char* cmd = argv[0]; /* original command path */
char* format = 0; /* tmxfmt() format */
char* string = 0; /* date string */
int elapsed = 0; /* args are start/stop pairs */
int filetime = 0; /* use this st_ time field */
int increment = 0; /* incrementally adjust time */
int last = 0; /* display the last time arg */
Tm_zone_t* listzones = 0; /* known time zone table */
int network = 0; /* don't set network time */
int show = 0; /* show date and don't set */
int unelapsed = 0; /* fmtelapsed() => strelapsed */
cmdinit(argc, argv, context, ERROR_CATALOG, 0);
setlocale(LC_ALL, "");
tm_info.flags = TM_DATESTYLE;
fmts = &fmt;
fmt.format = "";
fmt.next = 0;
for (;;)
{
switch (optget(argv, usage))
{
case 'a':
case 'c':
case 'm':
filetime = opt_info.option[1];
continue;
case 'd':
string = opt_info.arg;
show = 1;
continue;
case 'e':
format = "%#";
continue;
case 'E':
elapsed = 1;
continue;
case 'f':
format = opt_info.arg;
continue;
case 'i':
increment = 1;
continue;
case 'l':
tm_info.flags |= TM_LEAP;
continue;
case 'L':
last = 1;
continue;
case 'n':
network = 1;
continue;
case 'p':
if (!(f = newof(0, Fmt_t, 1, 0)))
error(ERROR_SYSTEM|3, "out of space [format]");
f->next = fmts;
f->format = opt_info.arg;
fmts = f;
continue;
case 's':
show = 1;
continue;
case 'u':
tm_info.flags |= TM_UTC;
continue;
case 'U':
unelapsed = (int)opt_info.num;
continue;
case 'z':
listzones = tm_data.zone;
continue;
case '?':
error(ERROR_USAGE|4, "%s", opt_info.arg);
continue;
case ':':
error(2, "%s", opt_info.arg);
continue;
}
break;
}
argv += opt_info.index;
if (error_info.errors)
error(ERROR_USAGE|4, "%s", optusage(NiL));
now = tmxgettime();
if (listzones)
{
s = "-";
while (listzones->standard)
{
if (listzones->type)
s = listzones->type;
sfprintf(sfstdout, "%3s %4s %4s %4d %4d\n", s, *listzones->standard ? listzones->standard : "-", listzones->daylight ? listzones->daylight : "-", listzones->west, listzones->dst);
listzones++;
show = 1;
}
}
else if (elapsed)
{
e = 0;
while (s = *argv++)
{
if (!(t = *argv++))
{
argv--;
t = "now";
}
ts = convert(fmts, s, now);
te = convert(fmts, t, now);
if (te > ts)
e += te - ts;
else
e += ts - te;
}
sfputr(sfstdout, fmtelapsed((unsigned long)tmxsec(e), 1), '\n');
show = 1;
}
else if (unelapsed)
{
while (s = *argv++)
{
u = strelapsed(s, &t, unelapsed);
if (*t)
error(3, "%s: invalid elapsed time", s);
sfprintf(sfstdout, "%lu\n", u);
}
show = 1;
}
else if (filetime)
{
if (!*argv)
error(ERROR_USAGE|4, "%s", optusage(NiL));
n = argv[1] != 0;
while (s = *argv++)
{
if (stat(s, &st))
error(2, "%s: not found", s);
else
{
switch (filetime)
{
case 'a':
now = tmxgetatime(&st);
break;
case 'c':
now = tmxgetctime(&st);
break;
default:
now = tmxgetmtime(&st);
break;
}
tmxfmt(buf, sizeof(buf), format, now);
if (n)
sfprintf(sfstdout, "%s: %s\n", s, buf);
else
sfprintf(sfstdout, "%s\n", buf);
show = 1;
}
}
}
else
{
if ((s = *argv) && !format && *s == '+')
{
format = s + 1;
argv++;
s = *argv;
}
if (s || (s = string))
{
if (*argv && string)
error(ERROR_USAGE|4, "%s", optusage(NiL));
now = convert(fmts, s, now);
if (*argv && (s = *++argv))
{
show = 1;
do
{
if (!last)
{
tmxfmt(buf, sizeof(buf), format, now);
sfprintf(sfstdout, "%s\n", buf);
}
now = convert(fmts, s, now);
} while (s = *++argv);
}
}
else
show = 1;
if (format || show)
{
tmxfmt(buf, sizeof(buf), format, now);
sfprintf(sfstdout, "%s\n", buf);
}
else if (settime(context, cmd, now, increment, network))
error(ERROR_SYSTEM|3, "cannot set system time");
}
while (fmts != &fmt)
{
f = fmts;
fmts = fmts->next;
free(f);
}
tm_info.flags = 0;
if (show && sfsync(sfstdout))
error(ERROR_system(0), "write error");
return error_info.errors != 0;
}