** Originally written by Steven M. Bellovin <smb@research.att.com> while
** at the University of North Carolina at Chapel Hill. Later tweaked by
** a couple of people on Usenet. Completely overhauled by Rich $alz
** <rsalz@bbn.com> and Jim Berets <jberets@bbn.com> in August, 1990;
** send any email to Rich.
** This grammar has eight shift/reduce conflicts.
** This code is in the public domain and has no copyright.
/* SUPPRESS 287 on yaccpar_sccsid *//* Unusd static variable */
/* SUPPRESS 288 on yyerrlab *//* Label unused */
#define alloca __builtin_alloca
#ifdef _AIX /* for Bison */
** Uncomment the next line if you need to do a tzset() call to set the
** timezone, and don't have ftime(). Some SystemV releases, I think.
time_t time; /* Seconds since the epoch */
unsigned short millitm; /* Field not used */
short dstflag; /* Field not used */
#endif /* defined(USG) */
#if defined(BSD4_2) || defined(BSD4_1C)
#endif /* defined(BSD4_2) */
#endif /* defined(vms) */
#if defined (STDC_HEADERS) || defined (USG)
extern struct tm *localtime();
#define yyparse getdate_yyparse
#define yylex getdate_yylex
#define yyerror getdate_yyerror
#if !defined(lint) && !defined(SABER)
"$Header: str2date.y,v 2.1 90/09/06 08:15:06 cronan Exp $";
#endif /* !defined(lint) && !defined(SABER) */
#define SECSPERDAY (24L * 60L * 60L)
** An entry in the lexical lookup table.
** Daylight-savings mode: on, off, or not yet known.
** Meridian: am, pm, or 24-hour style.
** Global variables. We could get rid of most of these by using a good
** union as the yacc stack. (This routine was originally written before
** yacc had the %union construct.) Maybe someday; right now we only use
** the %union very rarely.
static DSTMODE yyDSTmode;
static time_t yyDayOrdinal;
static time_t yyDayNumber;
static time_t yyTimezone;
static MERIDIAN yyMeridian;
static time_t yyRelMonth;
static time_t yyRelSeconds;
%token tAGO tDAY tDAYZONE tID tMERIDIAN tMINUTE_UNIT tMONTH tMONTH_UNIT
%token tSEC_UNIT tSNUMBER tUNUMBER tZONE
%type <Number> tDAY tDAYZONE tMINUTE_UNIT tMONTH tMONTH_UNIT
%type <Number> tSEC_UNIT tSNUMBER tUNUMBER tZONE
%type <Meridian> tMERIDIAN o_merid
time : tUNUMBER tMERIDIAN {
| tUNUMBER ':' tUNUMBER o_merid {
| tUNUMBER ':' tUNUMBER tSNUMBER {
yyTimezone = - ($4 % 100 + ($4 / 100) * 60);
| tUNUMBER ':' tUNUMBER ':' tUNUMBER o_merid {
| tUNUMBER ':' tUNUMBER ':' tUNUMBER tSNUMBER {
yyTimezone = - ($6 % 100 + ($6 / 100) * 60);
date : tUNUMBER '/' tUNUMBER {
| tUNUMBER '/' tUNUMBER '/' tUNUMBER {
| tMONTH tUNUMBER ',' tUNUMBER {
| tUNUMBER tMONTH tUNUMBER {
yyRelSeconds = -yyRelSeconds;
yyRelMonth = -yyRelMonth;
relunit : tUNUMBER tMINUTE_UNIT {
yyRelSeconds += $1 * $2 * 60L;
| tSNUMBER tMINUTE_UNIT {
yyRelSeconds += $1 * $2 * 60L;
yyRelSeconds += $1 * 60L;
if (yyHaveTime && yyHaveDate && !yyHaveRel)
yyMonth= (date_part/100)%100;
yyYear = date_part/10000;
/* Month and day table. */
static TABLE MonthDayTable[] = {
{ "january", tMONTH, 1 },
{ "february", tMONTH, 2 },
{ "september", tMONTH, 9 },
{ "october", tMONTH, 10 },
{ "november", tMONTH, 11 },
{ "december", tMONTH, 12 },
{ "wednesday", tDAY, 3 },
static TABLE UnitsTable[] = {
{ "year", tMONTH_UNIT, 12 },
{ "month", tMONTH_UNIT, 1 },
{ "fortnight", tMINUTE_UNIT, 14 * 24 * 60 },
{ "week", tMINUTE_UNIT, 7 * 24 * 60 },
{ "day", tMINUTE_UNIT, 1 * 24 * 60 },
{ "hour", tMINUTE_UNIT, 60 },
{ "minute", tMINUTE_UNIT, 1 },
{ "min", tMINUTE_UNIT, 1 },
{ "second", tSEC_UNIT, 1 },
/* Assorted relative-time words. */
static TABLE OtherTable[] = {
{ "tomorrow", tMINUTE_UNIT, 1 * 24 * 60 },
{ "yesterday", tMINUTE_UNIT, -1 * 24 * 60 },
{ "today", tMINUTE_UNIT, 0 },
{ "now", tMINUTE_UNIT, 0 },
{ "last", tUNUMBER, -1 },
{ "this", tMINUTE_UNIT, 0 },
{ "first", tUNUMBER, 1 },
/* { "second", tUNUMBER, 2 }, */
{ "third", tUNUMBER, 3 },
{ "fourth", tUNUMBER, 4 },
{ "fifth", tUNUMBER, 5 },
{ "sixth", tUNUMBER, 6 },
{ "seventh", tUNUMBER, 7 },
{ "eighth", tUNUMBER, 8 },
{ "ninth", tUNUMBER, 9 },
{ "tenth", tUNUMBER, 10 },
{ "eleventh", tUNUMBER, 11 },
{ "twelfth", tUNUMBER, 12 },
/* The timezone table. */
static TABLE TimezoneTable[] = {
{ "gmt", tZONE, HOUR( 0) }, /* Greenwich Mean */
{ "ut", tZONE, HOUR( 0) }, /* Universal (Coordinated) */
{ "utc", tZONE, HOUR( 0) },
{ "wet", tZONE, HOUR( 0) }, /* Western European */
{ "bst", tDAYZONE, HOUR( 0) }, /* British Summer */
{ "wat", tZONE, HOUR( 1) }, /* West Africa */
{ "at", tZONE, HOUR( 2) }, /* Azores */
/* For completeness. BST is also British Summer, and GST is
{ "bst", tZONE, HOUR( 3) }, /* Brazil Standard */
{ "gst", tZONE, HOUR( 3) }, /* Greenland Standard */
{ "nft", tZONE, HOUR(3.5) }, /* Newfoundland */
{ "nst", tZONE, HOUR(3.5) }, /* Newfoundland Standard */
{ "ndt", tDAYZONE, HOUR(3.5) }, /* Newfoundland Daylight */
{ "ast", tZONE, HOUR( 4) }, /* Atlantic Standard */
{ "adt", tDAYZONE, HOUR( 4) }, /* Atlantic Daylight */
{ "est", tZONE, HOUR( 5) }, /* Eastern Standard */
{ "edt", tDAYZONE, HOUR( 5) }, /* Eastern Daylight */
{ "cst", tZONE, HOUR( 6) }, /* Central Standard */
{ "cdt", tDAYZONE, HOUR( 6) }, /* Central Daylight */
{ "mst", tZONE, HOUR( 7) }, /* Mountain Standard */
{ "mdt", tDAYZONE, HOUR( 7) }, /* Mountain Daylight */
{ "pst", tZONE, HOUR( 8) }, /* Pacific Standard */
{ "pdt", tDAYZONE, HOUR( 8) }, /* Pacific Daylight */
{ "yst", tZONE, HOUR( 9) }, /* Yukon Standard */
{ "ydt", tDAYZONE, HOUR( 9) }, /* Yukon Daylight */
{ "hst", tZONE, HOUR(10) }, /* Hawaii Standard */
{ "hdt", tDAYZONE, HOUR(10) }, /* Hawaii Daylight */
{ "cat", tZONE, HOUR(10) }, /* Central Alaska */
{ "ahst", tZONE, HOUR(10) }, /* Alaska-Hawaii Standard */
{ "nt", tZONE, HOUR(11) }, /* Nome */
{ "idlw", tZONE, HOUR(12) }, /* International Date Line West */
{ "cet", tZONE, -HOUR(1) }, /* Central European */
{ "met", tZONE, -HOUR(1) }, /* Middle European */
{ "mewt", tZONE, -HOUR(1) }, /* Middle European Winter */
{ "mest", tDAYZONE, -HOUR(1) }, /* Middle European Summer */
{ "swt", tZONE, -HOUR(1) }, /* Swedish Winter */
{ "sst", tDAYZONE, -HOUR(1) }, /* Swedish Summer */
{ "fwt", tZONE, -HOUR(1) }, /* French Winter */
{ "fst", tDAYZONE, -HOUR(1) }, /* French Summer */
{ "eet", tZONE, -HOUR(2) }, /* Eastern Europe, USSR Zone 1 */
{ "bt", tZONE, -HOUR(3) }, /* Baghdad, USSR Zone 2 */
{ "it", tZONE, -HOUR(3.5) },/* Iran */
{ "zp4", tZONE, -HOUR(4) }, /* USSR Zone 3 */
{ "zp5", tZONE, -HOUR(5) }, /* USSR Zone 4 */
{ "ist", tZONE, -HOUR(5.5) },/* Indian Standard */
{ "zp6", tZONE, -HOUR(6) }, /* USSR Zone 5 */
/* For completeness. NST is also Newfoundland Stanard, nad SST is
* also Swedish Summer. */
{ "nst", tZONE, -HOUR(6.5) },/* North Sumatra */
{ "sst", tZONE, -HOUR(7) }, /* South Sumatra, USSR Zone 6 */
{ "wast", tZONE, -HOUR(7) }, /* West Australian Standard */
{ "wadt", tDAYZONE, -HOUR(7) }, /* West Australian Daylight */
{ "jt", tZONE, -HOUR(7.5) },/* Java (3pm in Cronusland!) */
{ "cct", tZONE, -HOUR(8) }, /* China Coast, USSR Zone 7 */
{ "jst", tZONE, -HOUR(9) }, /* Japan Standard, USSR Zone 8 */
{ "cast", tZONE, -HOUR(9.5) },/* Central Australian Standard */
{ "cadt", tDAYZONE, -HOUR(9.5) },/* Central Australian Daylight */
{ "east", tZONE, -HOUR(10) }, /* Eastern Australian Standard */
{ "eadt", tDAYZONE, -HOUR(10) }, /* Eastern Australian Daylight */
{ "gst", tZONE, -HOUR(10) }, /* Guam Standard, USSR Zone 9 */
{ "nzt", tZONE, -HOUR(12) }, /* New Zealand */
{ "nzst", tZONE, -HOUR(12) }, /* New Zealand Standard */
{ "nzdt", tDAYZONE, -HOUR(12) }, /* New Zealand Daylight */
{ "idle", tZONE, -HOUR(12) }, /* International Date Line East */
/* Military timezone table. */
static TABLE MilitaryTable[] = {
{ "a", tZONE, HOUR( 1) },
{ "b", tZONE, HOUR( 2) },
{ "c", tZONE, HOUR( 3) },
{ "d", tZONE, HOUR( 4) },
{ "e", tZONE, HOUR( 5) },
{ "f", tZONE, HOUR( 6) },
{ "g", tZONE, HOUR( 7) },
{ "h", tZONE, HOUR( 8) },
{ "i", tZONE, HOUR( 9) },
{ "k", tZONE, HOUR( 10) },
{ "l", tZONE, HOUR( 11) },
{ "m", tZONE, HOUR( 12) },
{ "n", tZONE, HOUR(- 1) },
{ "o", tZONE, HOUR(- 2) },
{ "p", tZONE, HOUR(- 3) },
{ "q", tZONE, HOUR(- 4) },
{ "r", tZONE, HOUR(- 5) },
{ "s", tZONE, HOUR(- 6) },
{ "t", tZONE, HOUR(- 7) },
{ "u", tZONE, HOUR(- 8) },
{ "v", tZONE, HOUR(- 9) },
{ "w", tZONE, HOUR(-10) },
{ "x", tZONE, HOUR(-11) },
{ "y", tZONE, HOUR(-12) },
{ "z", tZONE, HOUR( 0) },
ToSeconds(Hours, Minutes, Seconds, Meridian)
if (Minutes < 0 || Minutes > 59 || Seconds < 0 || Seconds > 59)
if (Hours < 0 || Hours > 23)
return (Hours * 60L + Minutes) * 60L + Seconds;
if (Hours < 1 || Hours > 12)
return (Hours * 60L + Minutes) * 60L + Seconds;
if (Hours < 1 || Hours > 12)
return ((Hours + 12) * 60L + Minutes) * 60L + Seconds;
Convert(Month, Day, Year, Hours, Minutes, Seconds, Meridian, DSTmode)
static int DaysInMonth[12] = {
31, 0, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
DaysInMonth[1] = Year % 4 == 0 && (Year % 100 != 0 || Year % 400 == 0)
if (Year < EPOCH || Year > 1999
|| Month < 1 || Month > 12
/* Lint fluff: "conversion from long may lose accuracy" */
|| Day < 1 || Day > DaysInMonth[(int)--Month])
for (Julian = Day - 1, i = 0; i < Month; i++)
Julian += DaysInMonth[i];
for (i = EPOCH; i < Year; i++)
Julian += 365 + (i % 4 == 0);
Julian += yyTimezone * 60L;
if ((tod = ToSeconds(Hours, Minutes, Seconds, Meridian)) < 0)
|| (DSTmode == DSTmaybe && localtime(&Julian)->tm_isdst))
DSTcorrect(Start, Future)
StartDay = (localtime(&Start)->tm_hour + 1) % 24;
FutureDay = (localtime(&Future)->tm_hour + 1) % 24;
return (Future - Start) + (StartDay - FutureDay) * 60L * 60L;
RelativeDate(Start, DayOrdinal, DayNumber)
now += SECSPERDAY * ((DayNumber - tm->tm_wday + 7) % 7);
now += 7 * SECSPERDAY * (DayOrdinal <= 0 ? DayOrdinal : DayOrdinal - 1);
return DSTcorrect(Start, now);
RelativeMonth(Start, RelMonth)
Month = 12 * tm->tm_year + tm->tm_mon + RelMonth;
Convert(Month, (time_t)tm->tm_mday, Year,
(time_t)tm->tm_hour, (time_t)tm->tm_min, (time_t)tm->tm_sec,
if (strcmp(buff, "am") == 0 || strcmp(buff, "a.m.") == 0) {
if (strcmp(buff, "pm") == 0 || strcmp(buff, "p.m.") == 0) {
/* See if we have an abbreviation for a month. */
else if (strlen(buff) == 4 && buff[3] == '.') {
for (tp = MonthDayTable; tp->name; tp++) {
if (strncmp(buff, tp->name, 3) == 0) {
yylval.Number = tp->value;
else if (strcmp(buff, tp->name) == 0) {
yylval.Number = tp->value;
for (tp = TimezoneTable; tp->name; tp++)
if (strcmp(buff, tp->name) == 0) {
yylval.Number = tp->value;
for (tp = UnitsTable; tp->name; tp++)
if (strcmp(buff, tp->name) == 0) {
yylval.Number = tp->value;
/* Strip off any plural and try the units table again. */
for (tp = UnitsTable; tp->name; tp++)
if (strcmp(buff, tp->name) == 0) {
yylval.Number = tp->value;
buff[i] = 's'; /* Put back for "this" in OtherTable. */
for (tp = OtherTable; tp->name; tp++)
if (strcmp(buff, tp->name) == 0) {
yylval.Number = tp->value;
/* Military timezones. */
if (buff[1] == '\0' && isalpha(*buff)) {
for (tp = MilitaryTable; tp->name; tp++)
if (strcmp(buff, tp->name) == 0) {
yylval.Number = tp->value;
/* Drop out any periods and try the timezone table again. */
for (i = 0, p = q = buff; *q; q++)
for (tp = TimezoneTable; tp->name; tp++)
if (strcmp(buff, tp->name) == 0) {
yylval.Number = tp->value;
while (isspace(*yyInput))
if (isdigit(c = *yyInput) || c == '-' || c == '+') {
if (c == '-' || c == '+') {
sign = c == '-' ? -1 : 1;
if (!isdigit(*++yyInput))
for (yylval.Number = 0; isdigit(c = *yyInput++); )
yylval.Number = 10 * yylval.Number + c - '0';
yylval.Number = -yylval.Number;
return sign ? tSNUMBER : tUNUMBER;
for (p = buff; isalpha(c = *yyInput++) || c == '.'; )
if (p < &buff[sizeof buff - 1])
/* Set the timezone global. */
ftz.timezone = (int) timezone / 60;
#endif /* defined(NEED_TZSET) */
tm = localtime(&now->time);
yyMonth = tm->tm_mon + 1;
yyTimezone = now->timezone;
|| yyHaveTime > 1 || yyHaveZone > 1 || yyHaveDate > 1 || yyHaveDay > 1)
if (yyHaveDate || yyHaveTime || yyHaveDay) {
Start = Convert(yyMonth, yyDay, yyYear, yyHour, yyMinutes, yySeconds,
Start -= ((tm->tm_hour * 60L + tm->tm_min) * 60L) + tm->tm_sec;
Start += RelativeMonth(Start, yyRelMonth);
if (yyHaveDay && !yyHaveDate) {
tod = RelativeDate(Start, yyDayOrdinal, yyDayNumber);
/* Have to do *something* with a legitimate -1 so it's distinguishable
* from the error return value. (Alternately could set errno on error.) */
return Start == -1 ? 0 : Start;
(void)printf("Enter date, or blank line to exit.\n\t> ");
while (gets(buff) && buff[0]) {
d = get_date(buff, (struct timeb *)NULL);
(void)printf("Bad format - couldn't convert.\n");
(void)printf("%s", ctime(&d));
#endif /* defined(TEST) */