date.y

linux下的E_MAIL客户端源码

%{
/*
 *  Project   : tin - a Usenet reader
 *  Module    : parsedate.y
 *  Author    : S.Bellovin & R.$alz & J.Berets & P.Eggert
 *  Created   : 01-08-90
 *  Updated   : 04-12-92
 *  Notes     : This grammar has 11 shift/reduce conflicts.
 *              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. 
 *              Further revised (removed obsolete constructs and cleaned up 
 *              timezone names) in August, 1991, by Rich.
 *              Paul Eggert <[e-mail]> helped in September 1992.
 *              Further changes by Evgeny Stambulchik; mostly workarounds
 *              to make the code more tolerable. 2000-2001
 *  Revision  : 1.13
 *  Copyright : This code is in the public domain and has no copyright.
 */

/* SUPPRESS 530 *//* Empty body for statement */
/* SUPPRESS 593 on yyerrlab *//* Label was not used */
/* SUPPRESS 593 on yynewstate *//* Label was not used */
/* SUPPRESS 595 on yypvt *//* Automatic variable may be used before set */

#include "date.h"

/*
**  Get the number of elements in a fixed-size array, or a pointer just
**  past the end of it.
*/
#define SIZEOF(array)	((int)(sizeof array / sizeof array[0]))
#define ENDOF(array)	(&array[SIZEOF(array)])

#define CTYPE(isXXXXX, c)	((isascii((c)) && isXXXXX((c))))

typedef char	*STRING;

#define yyparse		date_parse
#define yylex		date_lex
#define yyerror		date_error


    /* See the LeapYears table in Convert. */
#define EPOCH		1970
#define END_OF_TIME	2038

    /* Constants for general time calculations. */
#define DST_OFFSET	1
#define SECSPERDAY	(24L * 60L * 60L)
    /* Readability for TABLE stuff. */
#define HOUR(x)		(x * 60)

#define LPAREN		'('
#define RPAREN		')'
#define IS7BIT(x)	((unsigned int)(x) < 0200)


/*
**  An entry in the lexical lookup table.
*/
typedef struct _TABLE {
    STRING	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 them by using a yacc
**  union, but this is more efficient.  (This routine predates the
**  yacc %union construct.)
*/
static char	*yyInput;
static DSTMODE	yyDSTmode;
static int	yyHaveDate;
static int	yyHaveRel;
static int	yyHaveTime;
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;


extern struct tm	*localtime();

static void		date_error();
%}

%union {
    time_t		Number;
    enum _MERIDIAN	Meridian;
}

%token	tDAY tDAYZONE tMERIDIAN tMONTH tMONTH_UNIT tSEC_UNIT
%token	tUNUMBER tUNKNOWN tZONE

%type	<Number>	tDAYZONE tMONTH tMONTH_UNIT tSEC_UNIT
%type	<Number>	tUNUMBER tZONE s_number numzone zone qzone
%type	<Meridian>	tMERIDIAN o_merid

%%

spec	: /* NULL */
	| spec item
	;

item	: time {
	    yyHaveTime++;
#if	defined(lint)
	    /* I am compulsive about lint natterings... */
	    if (yyHaveTime == -1) {
		YYERROR;
	    }
#endif	/* defined(lint) */
	}
	| time zone {
	    yyHaveTime++;
	    yyTimezone = $2;
	}
	| time qzone {
	    yyHaveTime++;
	    yyTimezone = $2;
	}
	| time junkzone {
	    yyHaveTime++;
	}
	| date {
	    yyHaveDate++;
	}
	| rel {
	    yyHaveRel = 1;
	}
	;

time	: tUNUMBER o_merid {
	    if ($1 < 100) {
		yyHour = $1;
		yyMinutes = 0;
	    }
	    else {
		yyHour = $1 / 100;
		yyMinutes = $1 % 100;
	    }
	    yySeconds = 0;
	    yyMeridian = $2;
	}
	| tUNUMBER ':' tUNUMBER o_merid {
	    yyHour = $1;
	    yyMinutes = $3;
	    yySeconds = 0;
	    yyMeridian = $4;
	}
	| tUNUMBER ':' tUNUMBER numzone {
	    yyHour = $1;
	    yyMinutes = $3;
	    yyTimezone = $4;
	    yyMeridian = MER24;
	    yyDSTmode = DSToff;
	}
	| tUNUMBER ':' tUNUMBER ':' tUNUMBER o_merid {
	    yyHour = $1;
	    yyMinutes = $3;
	    yySeconds = $5;
	    yyMeridian = $6;
	}
	| tUNUMBER ':' tUNUMBER ':' tUNUMBER numzone {
	    yyHour = $1;
	    yyMinutes = $3;
	    yySeconds = $5;
	    yyTimezone = $6;
	    yyMeridian = MER24;
	    yyDSTmode = DSToff;
	}
	;

zone	: tZONE {
	    $$ = $1;
	    yyDSTmode = DSToff;
	}
	| tDAYZONE {
	    $$ = $1;
	    yyDSTmode = DSTon;
	}
	| tZONE numzone {
	    /* Only allow "GMT+300" and "GMT-0800" */
	    if ($1 != 0) {
		YYABORT;
	    }
	    $$ = $2;
	    yyDSTmode = DSToff;
	}
	| numzone {
	    $$ = $1;
	    yyDSTmode = DSToff;
	}
	;

qzone	: '"' zone '"' {
	    $$ = $2;
	}

junkzone : tUNKNOWN {
	}
        | tUNKNOWN tUNKNOWN {
        }
        | tUNKNOWN tUNKNOWN tUNKNOWN {
        }

numzone	: s_number {
	    int	i;
	                
	    /* Unix and GMT and numeric timezones -- a little confusing. */
	    if ($1 < 0) {
		/* Don't work with negative modulus. */
		$1 = -$1;
	 	if ($1 > 9999 || (i = $1 % 100) >= 60) {
	 		YYABORT;
	 	}
		$$ = ($1 / 100) * 60 + i;
	    }
	    else {
	 	if ($1 > 9999 || (i = $1 % 100) >= 60) {
	 		YYABORT;
	 	}
		$$ = -(($1 / 100) * 60 + i);
	    }
	}
	;

date	: tUNUMBER '/' tUNUMBER {
	    yyMonth = $1;
	    yyDay = $3;
	}
	| tUNUMBER '/' tUNUMBER '/' tUNUMBER {
	    if ($1 > 100) {
		yyYear = $1;
		yyMonth = $3;
		yyDay = $5;
	    }
	    else {
		yyMonth = $1;
		yyDay = $3;
		yyYear = $5;
	    }
	}
	| tUNUMBER '-' tUNUMBER '-' tUNUMBER {
	    yyYear = $1;
	    yyMonth = $3;
	    yyDay = $5;
	}
	| tMONTH tUNUMBER {
	    yyMonth = $1;
	    yyDay = $2;
	}
	| tMONTH tUNUMBER ',' tUNUMBER {
	    yyMonth = $1;
	    yyDay = $2;
	    yyYear = $4;
	}
	| tUNUMBER tMONTH {
	    yyDay = $1;
	    yyMonth = $2;
	}
	| tUNUMBER tMONTH tUNUMBER {
	    yyDay = $1;
	    yyMonth = $2;
	    yyYear = $3;
	}
	| tDAY ',' tUNUMBER tMONTH tUNUMBER {
	    yyDay = $3;
	    yyMonth = $4;
	    yyYear = $5;
	}
	;

rel	: s_number tSEC_UNIT {
	    yyRelSeconds += $1 * $2;
	}
	| tUNUMBER tSEC_UNIT {
	    yyRelSeconds += $1 * $2;
	}
	| s_number tMONTH_UNIT {
	    yyRelMonth += $1 * $2;
	}
	| tUNUMBER tMONTH_UNIT {
	    yyRelMonth += $1 * $2;
	}
	;

o_merid	: /* NULL */ {
	    $$ = MER24;
	}
	| tMERIDIAN {
	    $$ = $1;
	}
	;

s_number : '-' tUNUMBER {
	    $$ = -$2;
        }
        |  '+' tUNUMBER {
	    $$ = $2;
        }

%%

/* 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 },
    { "october",	tMONTH, 10 },
    { "november",	tMONTH, 11 },
    { "december",	tMONTH, 12 },
	/* The value of the day isn't used... */
    { "sunday",		tDAY, 0 },
    { "monday",		tDAY, 0 },
    { "tuesday",	tDAY, 0 },
    { "wednesday",	tDAY, 0 },
    { "thursday",	tDAY, 0 },
    { "friday",		tDAY, 0 },
    { "saturday",	tDAY, 0 },
};

/* Time units table. */
static TABLE	UnitsTable[] = {
    { "year",		tMONTH_UNIT,	12 },
    { "month",		tMONTH_UNIT,	1 },
    { "week",		tSEC_UNIT,	7 * 24 * 60 * 60 },
    { "day",		tSEC_UNIT,	1 * 24 * 60 * 60 },
    { "hour",		tSEC_UNIT,	60 * 60 },
    { "minute",		tSEC_UNIT,	60 },
    { "min",		tSEC_UNIT,	60 },
    { "second",		tSEC_UNIT,	1 },
    { "sec",		tSEC_UNIT,	1 },
};

/* Timezone table. */
static TABLE	TimezoneTable[] = {
    { "gmt",	tZONE,     HOUR( 0) },	/* Greenwich Mean */
    { "ut",	tZONE,     HOUR( 0) },	/* Universal */
    { "utc",	tZONE,     HOUR( 0) },	/* Universal Coordinated */
    { "cut",	tZONE,     HOUR( 0) },	/* Coordinated Universal */
    { "z",	tZONE,     HOUR( 0) },	/* Greenwich Mean */
    { "wet",	tZONE,     HOUR( 0) },	/* Western European */
    { "bst",	tDAYZONE,  HOUR( 0) },	/* British Summer */
    { "nst",	tZONE,     HOUR(3)+30 }, /* Newfoundland Standard */
    { "ndt",	tDAYZONE,  HOUR(3)+30 }, /* 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 */
    { "akst",	tZONE,     HOUR( 9) },	/* Alaska Standard */
    { "akdt",	tDAYZONE,  HOUR( 9) },	/* Alaska Daylight */
    { "hst",	tZONE,     HOUR(10) },	/* Hawaii Standard */
    { "hast",	tZONE,     HOUR(10) },	/* Hawaii-Aleutian Standard */
    { "hadt",	tDAYZONE,  HOUR(10) },	/* Hawaii-Aleutian Daylight */
    { "ces",	tDAYZONE,  -HOUR(1) },	/* Central European Summer */
    { "cest",	tDAYZONE,  -HOUR(1) },	/* Central European Summer */
    { "mez",	tZONE,     -HOUR(1) },	/* Middle European */
    { "mezt",	tDAYZONE,  -HOUR(1) },	/* Middle European Summer */
    { "cet",	tZONE,     -HOUR(1) },	/* Central European */
    { "met",	tZONE,     -HOUR(1) },	/* Middle European */
    { "eet",	tZONE,     -HOUR(2) },	/* Eastern Europe */
    { "msk",	tZONE,     -HOUR(3) },	/* Moscow Winter */
    { "msd",	tDAYZONE,  -HOUR(3) },	/* Moscow Summer */
    { "wast",	tZONE,     -HOUR(8) },	/* West Australian Standard */
    { "wadt",	tDAYZONE,  -HOUR(8) },	/* West Australian Daylight */
    { "hkt",	tZONE,     -HOUR(8) },	/* Hong Kong */
    { "cct",	tZONE,     -HOUR(8) },	/* China Coast */
    { "jst",	tZONE,     -HOUR(9) },	/* Japan Standard */
    { "kst",	tZONE,     -HOUR(9) },	/* Korean Standard */
    { "kdt",	tZONE,     -HOUR(9) },	/* Korean Daylight */
    { "cast",	tZONE,     -(HOUR(9)+30) }, /* Central Australian Standard */
    { "cadt",	tDAYZONE,  -(HOUR(9)+30) }, /* Central Australian Daylight */
    { "east",	tZONE,     -HOUR(10) },	/* Eastern Australian Standard */
    { "eadt",	tDAYZONE,  -HOUR(10) },	/* Eastern Australian Daylight */
    { "nzst",	tZONE,     -HOUR(12) },	/* New Zealand Standard */
    { "nzdt",	tDAYZONE,  -HOUR(12) },	/* New Zealand Daylight */

    /* For completeness we include the following entries. */
#if	0

    /* Duplicate names.  Either they conflict with a zone listed above
     * (which is either more likely to be seen or just been in circulation
     * longer), or they conflict with another zone in this section and
     * we could not reasonably choose one over the other. */
    { "fst",	tZONE,     HOUR( 2) },	/* Fernando De Noronha Standard */
    { "fdt",	tDAYZONE,  HOUR( 2) },	/* Fernando De Noronha Daylight */
    { "bst",	tZONE,     HOUR( 3) },	/* Brazil Standard */
    { "est",	tZONE,     HOUR( 3) },	/* Eastern Standard (Brazil) */
    { "edt",	tDAYZONE,  HOUR( 3) },	/* Eastern Daylight (Brazil) */
    { "wst",	tZONE,     HOUR( 4) },	/* Western Standard (Brazil) */
    { "wdt",	tDAYZONE,  HOUR( 4) },	/* Western Daylight (Brazil) */
    { "cst",	tZONE,     HOUR( 5) },	/* Chile Standard */
    { "cdt",	tDAYZONE,  HOUR( 5) },	/* Chile Daylight */
    { "ast",	tZONE,     HOUR( 5) },	/* Acre Standard */