Files
bash/examples/loadables/strptime.c
T
2024-04-25 15:50:39 -04:00

242 lines
7.7 KiB
C

/* strptime - take a date-time string and turn it into seconds since the epoch. */
/* See Makefile for compilation details. */
/*
Copyright (C) 2023 Free Software Foundation, Inc.
This file is part of GNU Bash.
Bash is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
Bash is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with Bash. If not, see <http://www.gnu.org/licenses/>.
*/
#include <config.h>
#if defined (HAVE_UNISTD_H)
# include <unistd.h>
#endif
#include "bashtypes.h"
#include "posixtime.h"
#include <stdio.h>
#include "builtins.h"
#include "shell.h"
#include "bashgetopt.h"
#include "common.h"
struct date_modifier
{
char *shorthand;
int incr;
};
static struct date_modifier date_time_modifiers[] =
{
{ "now", 0 },
{ "today", 0 },
{ "tomorrow", 24*60*60 },
{ "yesterday", -24*60*60 },
{ "day after tomorrow", 48*60*60 },
{ "two days ago", -48*60*60 },
{ "next week", 7*24*60*60 },
{ "last week", -7*24*60*60 },
{ "the day after tomorrow", 48*60*60 },
{ 0, 0 }
};
static char * const date_time_formats[] =
{
"%a %b %d %T %Z %Y", /* Unix date */
"%a %b %d %T %Y", /* Wkd Mon DD HH:MM:SS YYYY */
"%FT%T%z", /* ISO8601 time YYYY-mm-ddTHH:MM:SSzone */
"%FT%R%z", /* ISO8601 time YYYY-mm-ddTHH:MMzone */
"%G-%m-%dT%T%z", /* ISO8601 time YYYY-mm-ddTHH:MM:SSzone */
"%G-%m-%dT%R%z", /* ISO8601 time YYYY-mm-ddTHH:MMzone */
"%G-%m-%d", /* ISO8601 time YYYY-mm-dd */
/* Can't do 8601 time zone offset with colon or fractions of a second */
"%a, %d %b %Y %T %Z", /* RFC822/RFC2822 time */
"%a, %d %b %Y %T %z", /* RFC822/RFC2822 time */
"%D %T", /* mm/dd/yy HH:MM:SS */
"%D %R", /* mm/dd/yy HH:MM */
"%D %r", /* mm/dd/yy HH:MM:SS a.m. */
"%D %I:%M %p", /* mm/dd/yy HH:MM p.m. */
"%m/%d/%Y %T", /* mm/dd/YYYY HH:MM:SS */
"%m/%d/%Y %R", /* mm/dd/YYYY HH:MM */
"%m/%d/%Y %r", /* mm/dd/YYYY HH:MM:SS a.m */
"%m/%d/%Y %I:%M %p", /* mm/dd/YYYY HH:MM p.m. */
"%m-%d-%Y %T", /* mm-dd-YYYY HH:MM:SS */
"%m-%d-%Y %R", /* mm-dd-YYYY HH:MM */
"%m-%d-%Y %r", /* mm-dd-YYYY HH:MM:SS a.m. */
"%m-%d-%Y %I:%M %p", /* mm-dd-YYYY HH:MM p.m. */
"%Y/%m/%d %T", /* YYYY/mm/dd HH:MM:SS */
"%Y/%m/%d %R", /* YYYY/mm/dd HH:MM */
"%Y/%m/%d %r", /* YYYY/mm/dd hh:MM:SS a.m. */
"%F %T", /* YYYY-mm-dd HH:MM:SS */
"%F %r", /* YYYY-mm-dd HH:MM:SS p.m. */
"%F %R", /* YYYY-mm-dd HH:MM */
"%F %I:%M %p", /* YYYY-mm-dd HH:MM a.m. */
"%F", /* YYYY-mm-dd ISO8601 time */
"%T", /* HH:MM:SS */
"%H.%M.%S", /* HH.MM.SS */
/* From coreutils-9.2 date */
"%Y-%m-%dT%H:%M:%S%z", /* ISO8601 time */
"%Y-%m-%dT%H%z", /* ISO8601 time */
"%Y-%m-%dT%H:%M%z", /* ISO8601 time */
/* RFC 3339 time */
"%Y-%m-%d %H:%M:%S%z", /* RFC 3339 time */
"%Y-%m-%dT%H:%M:%S%z", /* RFC 3339 time */
/* more oddball formats */
"%m.%d.%Y %T", /* mm.dd.YYYY HH:MM:SS */
"%m.%d.%Y %R", /* mm.dd.YYYY HH:MM */
"%m.%d.%Y %r", /* mm.dd.YYYY HH:MM:SS a.m. */
"%m.%d.%Y %I:%M %p", /* mm.dd.YYYY HH:MM p.m. */
"%m/%d/%Y", /* mm/dd/YYYY */
"%d %B %Y %T", /* dd Month YYYY HH:MM:SS */
"%d %B %Y %R", /* dd Month YYYY HH:MM */
"%d %B %Y %r", /* dd Month YYYY HH:MM:SS a.m. */
"%d %B %Y %I:%M %p", /* dd Month YYYY HH:MM p.m. */
"%d %b %Y %T", /* dd Mon YYYY HH:MM:SS */
"%d %b %Y %R", /* dd Mon YYYY HH:MM */
"%d %b %Y %r", /* dd Mon YYYY HH:MM:SS a.m. */
"%d %b %Y %I:%M %p", /* dd Mon YYYY HH:MM p.m. */
"%b %d, %Y %T", /* Mon dd, YYYY HH:MM:SS */
"%b %d, %Y %R", /* Mon dd, YYYY HH:MM */
"%b %d, %Y %r", /* Mon dd, YYYY HH:MM:SS a.m. */
"%b %d, %Y %I:%M %p", /* Mon dd, YYYY HH:MM p.m. */
"%m-%b-%Y", /* dd-Mon-YYYY */
"%m-%b-%Y %T", /* dd-Mon-YYYY HH:MM:SS */
"%m-%b-%Y %R", /* dd-Mon-YYYY HH:MM */
"%m-%b-%Y %r", /* dd-Mon-YYYY HH:MM:SS a.m. */
"%m-%b-%Y %I:%M %p", /* dd-Mon-YYYY HH:MM p.m. */
"%d/%b/%Y:%T %z", /* NCSA log format dd/Mon/YYYY:HH:MM:SS zone */
"%d/%b/%Y:%T%z", /* NCSA log format dd/Mon/YYYY:HH:MM:SSzone */
/* No delimiters */
"%Y%m%d %T", /* YYYYMMDD HH:MM:SS */
"%Y%m%d %R", /* YYYYMMDD HH:MM */
"%Y%m%d %r", /* YYYYMMDD HH:MM:SS a.m. */
"%Y%m%d %I:%M %p", /* YYYYMMDD HH:MM p.m. */
"%Y%m%d %H:%M:%S%z", /* YYYYMMDD HH:MM:SSzone */
"%Y%m%dT%H:%M:%S%z", /* YYYYMMDDTHH:MM:SSzone */
"%Y%m%dT%T", /* YYYYMMDDTHH:MM:SS */
"%Y%m%dT%R", /* YYYYMMDDTHH:MM */
/* Non-US formats */
"%d-%m-%Y", /* dd-mm-YYYY */
"%d-%m-%Y %T", /* dd-mm-YYYY HH:MM:SS */
"%d-%m-%Y %R", /* dd-mm-YYYY HH:MM */
"%d-%m-%Y %r", /* dd-mm-YYYY HH:MM:SS a.m. */
"%d-%m-%Y %I:%M %p", /* dd-mm-YYYY HH:MM p.m. */
"%d/%m/%Y %T", /* dd/mm/YYYY HH:MM:SS */
"%d/%m/%Y %R", /* dd/mm/YYYY HH:MM */
"%d/%m/%Y %r", /* dd/mm/YYYY HH:MM:SS a.m. */
"%d/%m/%Y %I:%M %p", /* dd/mm/YYYY HH:MM p.m. */
"%Y-%d-%m %T", /* YYYY-dd-mm HH:MM:SS */
"%Y-%d-%m %R", /* YYYY-dd-mm HH:MM */
"%d-%m-%Y %T", /* dd-mm-YYYY HH:MM:SS */
"%d-%m-%Y %R", /* dd-mm-YYYY HH:MM */
"%d-%m-%Y %r", /* dd-mm-YYYY HH:MM:SS a.m. */
"%d-%m-%Y %I:%M %p", /* dd-mm-YYYY HH:MM p.m. */
"%d.%m.%Y %T", /* dd.mm.YYYY HH:MM:SS */
"%d.%m.%Y %R", /* dd.mm.YYYY HH:MM */
"%d.%m.%Y %r", /* dd.mm.YYYY HH:MM:SS a.m. */
"%d.%m.%Y %I:%M %p", /* dd.mm.YYYY HH:MM p.m. */
0
};
static void
inittime (time_t *clock, struct tm *timeptr)
{
timeptr = localtime (clock); /* for now */
/* but default to midnight */
timeptr->tm_hour = timeptr->tm_min = timeptr->tm_sec = 0;
/* and let the system figure out the right DST offset */
timeptr->tm_isdst = -1;
}
int
strptime_builtin (WORD_LIST *list)
{
char *s;
struct tm t, *tm;
time_t now, secs;
char *datestr;
int i;
if (no_options (list)) /* for now */
return (EX_USAGE);
list = loptend;
if (list == 0)
{
builtin_usage ();
return (EX_USAGE);
}
datestr = string_list (list);
if (datestr == 0 || *datestr == 0)
return (EXECUTION_SUCCESS);
now = getnow ();
secs = -1;
for (i = 0; date_time_modifiers[i].shorthand; i++)
{
if (STREQ (datestr, date_time_modifiers[i].shorthand))
{
secs = now + date_time_modifiers[i].incr;
break;
}
}
if (secs == -1)
{
/* init struct tm */
inittime (&now, tm);
t = *tm;
for (i = 0; date_time_formats[i]; i++)
{
s = strptime (datestr, date_time_formats[i], &t);
if (s == 0)
continue;
/* skip extra characters at the end for now */
secs = mktime (&t);
break;
}
}
printf ("%ld\n", secs);
return (EXECUTION_SUCCESS);
}
char *strptime_doc[] = {
"Convert a date-time string to seconds since the epoch.",
"",
"Take DATE-TIME, a date-time string, parse it against a set of common",
"date-time formats. If the string matches one of the formats, convert",
"it into seconds since the epoch and display the result.",
(char *)NULL
};
/* The standard structure describing a builtin command. bash keeps an array
of these structures. The flags must include BUILTIN_ENABLED so the
builtin can be used. */
struct builtin strptime_struct = {
"strptime", /* builtin name */
strptime_builtin, /* function implementing the builtin */
BUILTIN_ENABLED, /* initial flags for builtin */
strptime_doc, /* array of long documentation strings. */
"strptime date-time", /* usage synopsis; becomes short_doc */
0 /* reserved for internal use */
};