getdate.c

一个类似Unix下tar命令的tar程序

# line 2 "getdate.y"
/* $Revision: 2.1 $
**
**  Originally written by Steven M. Bellovin <[e-mail]> while
**  at the University of North Carolina at Chapel Hill.  Later tweaked by
**  a couple of people on Usenet.  Completely overhauled by Rich $alz
**  <[e-mail]> and Jim Berets <[e-mail]> 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 */

#ifdef __GNUC__
#define alloca __builtin_alloca
#else
#ifdef sparc
#include <alloca.h>
#else
#ifdef _AIX /* for Bison */
#pragma alloca
#else
char *alloca ();
#endif
#endif
#endif

#include <stdio.h>
#include <ctype.h>

#if	defined(vms)
#include <types.h>
#include <time.h>
#else
#include <sys/types.h>
#if	defined(USG)
/*
**  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.
*/
/*#define NEED_TZSET */
struct timeb {
    time_t		time;		/* Seconds since the epoch	*/
    unsigned short	millitm;	/* Field not used		*/
    short		timezone;
    short		dstflag;	/* Field not used		*/
};
#else
#include <sys/timeb.h>
#endif	/* defined(USG) */
#if	defined(BSD4_2) || defined(BSD4_1C)
#include <sys/time.h>
#else
#include <time.h>
#endif	/* defined(BSD4_2) */
#endif	/* defined(vms) */

#if defined (STDC_HEADERS) || defined (USG)
#include <string.h>
#endif

extern struct tm	*localtime();

#define yyparse getdate_yyparse
#define yylex getdate_yylex
#define yyerror getdate_yyerror

#if	!defined(lint) && !defined(SABER)
static char RCS[] =
	"$Header: str2date.y,v 2.1 90/09/06 08:15:06 cronan Exp $";
#endif	/* !defined(lint) && !defined(SABER) */


#define EPOCH		1970
#define HOUR(x)		(x * 60)
#define SECSPERDAY	(24L * 60L * 60L)


/*
**  An entry in the lexical lookup table.
*/
typedef struct _TABLE {
    char	*name;
    int		type;
    time_t	value;
} TABLE;


/*
**  Daylight-savings mode:  on, off, or not yet known.
*/
typedef enum _DSTMODE {
    DSTon, DSToff, DSTmaybe
} DSTMODE;

/*
**  Meridian:  am, pm, or 24-hour style.
*/
typedef enum _MERIDIAN {
    MERam, MERpm, MER24
} MERIDIAN;


/*
**  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 char	*yyInput;
static DSTMODE	yyDSTmode;
static time_t	yyDayOrdinal;
static time_t	yyDayNumber;
static int	yyHaveDate;
static int	yyHaveDay;
static int	yyHaveRel;
static int	yyHaveTime;
static int	yyHaveZone;
static time_t	yyTimezone;
static time_t	yyDay;
static time_t	yyHour;
static time_t	yyMinutes;
static time_t	yyMonth;
static time_t	yySeconds;
static time_t	yyYear;
static MERIDIAN	yyMeridian;
static time_t	yyRelMonth;
static time_t	yyRelSeconds;


# line 135 "getdate.y"
typedef union  {
    time_t		Number;
    enum _MERIDIAN	Meridian;
} YYSTYPE;
# define tAGO 257
# define tDAY 258
# define tDAYZONE 259
# define tID 260
# define tMERIDIAN 261
# define tMINUTE_UNIT 262
# define tMONTH 263
# define tMONTH_UNIT 264
# define tSEC_UNIT 265
# define tSNUMBER 266
# define tUNUMBER 267
# define tZONE 268
#define yyclearin yychar = -1
#define yyerrok yyerrflag = 0
extern int yychar;
extern int yyerrflag;
#ifndef YYMAXDEPTH
#define YYMAXDEPTH 150
#endif
YYSTYPE yylval, yyval;
typedef int yytabelem;
# define YYERRCODE 256

# line 331 "getdate.y"


/* Month and day table. */
static TABLE	MonthDayTable[] = {
    { "january",	tMONTH,  1 },
    { "february",	tMONTH,  2 },
    { "march",		tMONTH,  3 },
    { "april",		tMONTH,  4 },
    { "may",		tMONTH,  5 },
    { "june",		tMONTH,  6 },
    { "july",		tMONTH,  7 },
    { "august",		tMONTH,  8 },
    { "september",	tMONTH,  9 },
    { "sept",		tMONTH,  9 },
    { "october",	tMONTH, 10 },
    { "november",	tMONTH, 11 },
    { "december",	tMONTH, 12 },
    { "sunday",		tDAY, 0 },
    { "monday",		tDAY, 1 },
    { "tuesday",	tDAY, 2 },
    { "tues",		tDAY, 2 },
    { "wednesday",	tDAY, 3 },
    { "wednes",		tDAY, 3 },
    { "thursday",	tDAY, 4 },
    { "thur",		tDAY, 4 },
    { "thurs",		tDAY, 4 },
    { "friday",		tDAY, 5 },
    { "saturday",	tDAY, 6 },
    { NULL }
};

/* Time units table. */
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 },
    { "sec",		tSEC_UNIT,	1 },
    { NULL }
};

/* 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 },
    { "next",		tUNUMBER,	2 },
    { "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 },
    { "ago",		tAGO,	1 },
    { NULL }
};

/* 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 */
#if	0
    /* For completeness.  BST is also British Summer, and GST is
     * also Guam Standard. */
    { "bst",	tZONE,     HOUR( 3) },	/* Brazil Standard */
    { "gst",	tZONE,     HOUR( 3) },	/* Greenland Standard */
#endif
    { "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 */
#if	0
    /* 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 */
#endif	/* 0 */
    { "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 */
    {  NULL  }
};

/* 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) },
    { NULL }
};




/* ARGSUSED */
int
yyerror(s)
    char	*s;
{
  return 0;
}


static time_t
ToSeconds(Hours, Minutes, Seconds, Meridian)
    time_t	Hours;
    time_t	Minutes;
    time_t	Seconds;
    MERIDIAN	Meridian;
{
    if (Minutes < 0 || Minutes > 59 || Seconds < 0 || Seconds > 59)
	return -1;
    switch (Meridian) {
    case MER24:
	if (Hours < 0 || Hours > 23)
	    return -1;
	return (Hours * 60L + Minutes) * 60L + Seconds;
    case MERam:
	if (Hours < 1 || Hours > 12)
	    return -1;
	return (Hours * 60L + Minutes) * 60L + Seconds;
    case MERpm:
	if (Hours < 1 || Hours > 12)
	    return -1;
	return ((Hours + 12) * 60L + Minutes) * 60L + Seconds;
    }
    /* NOTREACHED */
}


static time_t
Convert(Month, Day, Year, Hours, Minutes, Seconds, Meridian, DSTmode)
    time_t	Month;
    time_t	Day;
    time_t	Year;
    time_t	Hours;
    time_t	Minutes;
    time_t	Seconds;
    MERIDIAN	Meridian;
    DSTMODE	DSTmode;
{
    static int	DaysInMonth[12] = {
	31, 0, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31
    };
    time_t	tod;
    time_t	Julian;
    int		i;

    if (Year < 0)
	Year = -Year;
    if (Year < 100)
	Year += 1900;
    DaysInMonth[1] = Year % 4 == 0 && (Year % 100 != 0 || Year % 400 == 0)
		    ? 29 : 28;
    if (Year < EPOCH || Year > 1999
     || Month < 1 || Month > 12
     /* Lint fluff:  "conversion from long may lose accuracy" */
     || Day < 1 || Day > DaysInMonth[(int)--Month])
	return -1;

    for (Julian = Day - 1, i = 0; i < Month; i++)
	Julian += DaysInMonth[i];
    for (i = EPOCH; i < Year; i++)
	Julian += 365 + (i % 4 == 0);
    Julian *= SECSPERDAY;
    Julian += yyTimezone * 60L;
    if ((tod = ToSeconds(Hours, Minutes, Seconds, Meridian)) < 0)
	return -1;
    Julian += tod;
    if (DSTmode == DSTon
     || (DSTmode == DSTmaybe && localtime(&Julian)->tm_isdst))
	Julian -= 60 * 60;
    return Julian;
}


static time_t
DSTcorrect(Start, Future)
    time_t	Start;
    time_t	Future;
{
    time_t	StartDay;
    time_t	FutureDay;

    StartDay = (localtime(&Start)->tm_hour + 1) % 24;
    FutureDay = (localtime(&Future)->tm_hour + 1) % 24;
    return (Future - Start) + (StartDay - FutureDay) * 60L * 60L;
}


static time_t
RelativeDate(Start, DayOrdinal, DayNumber)
    time_t	Start;
    time_t	DayOrdinal;
    time_t	DayNumber;
{
    struct tm	*tm;
    time_t	now;

    now = Start;
    tm = localtime(&now);
    now += SECSPERDAY * ((DayNumber - tm->tm_wday + 7) % 7);
    now += 7 * SECSPERDAY * (DayOrdinal <= 0 ? DayOrdinal : DayOrdinal - 1);
    return DSTcorrect(Start, now);
}


static time_t
RelativeMonth(Start, RelMonth)
    time_t	Start;
    time_t	RelMonth;
{
    struct tm	*tm;
    time_t	Month;
    time_t	Year;

    if (RelMonth == 0)
	return 0;
    tm = localtime(&Start);
    Month = 12 * tm->tm_year + tm->tm_mon + RelMonth;
    Year = Month / 12;
    Month = Month % 12 + 1;
    return DSTcorrect(Start,
	    Convert(Month, (time_t)tm->tm_mday, Year,
		(time_t)tm->tm_hour, (time_t)tm->tm_min, (time_t)tm->tm_sec,
		MER24, DSTmaybe));
}


static int
LookupWord(buff)
    char		*buff;
{
    register char	*p;
    register char	*q;
    register TABLE	*tp;
    int			i;
    int			abbrev;

    /* Make it lowercase. */
    for (p = buff; *p; p++)
	if (isupper(*p))
	    *p = tolower(*p);

    if (strcmp(buff, "am") == 0 || strcmp(buff, "a.m.") == 0) {
	yylval.Meridian = MERam;
	return tMERIDIAN;
    }
    if (strcmp(buff, "pm") == 0 || strcmp(buff, "p.m.") == 0) {
	yylval.Meridian = MERpm;
	return tMERIDIAN;
    }

    /* See if we have an abbreviation for a month. */
    if (strlen(buff) == 3)
	abbrev = 1;