From: Paul Eggert Date: Sat, 19 Feb 2000 00:25:54 +0000 (+0000) Subject: Handle two-digit years with leading zeros correctly. X-Git-Url: https://git.dogcows.com/gitweb?a=commitdiff_plain;h=3a19b8b0df660ab893ebb9ac5a3614fd196c9135;p=chaz%2Ftar Handle two-digit years with leading zeros correctly. (textint): New typedef. (parser_control): Changed from struct parser_control to typedef (for consistency). Member year changed from int to textint. All uses changed. (YYSTYPE): Removed; replaced by %union with int and textint members. (tID): Removed; not used. (tDAY, tDAY_UNIT, tDAYZONE, tHOUR_UNIT, tID, tLOCAL_ZONE, tMERIDIAN, tMINUTE_UNIT, tMONTH, tMONTH_UNIT tSEC_UNIT, tSNUMBER, tUNUMBER, tYEAR_UNIT, tZONE, o_merid): Now of type . (tSNUMBER, tUNUMBER): Now of type . (date, number, to_year): Use width of number in digits, not its value, to determine whether it's a 2-digit year, or a 2-digit time. (yylex): Store number of digits of numeric tokens. Return '?' for unknown identifiers, rather than (unused) tID. --- diff --git a/lib/getdate.y b/lib/getdate.y index 4fe084c..4b7c2e9 100644 --- a/lib/getdate.y +++ b/lib/getdate.y @@ -85,6 +85,14 @@ #define TM_YEAR_BASE 1900 #define HOUR(x) ((x) * 60) + +/* An integer value, and the number of digits in its textual + representation. */ +typedef struct +{ + int value; + int digits; +} textint; /* An entry in the lexical lookup table. */ typedef struct @@ -98,7 +106,7 @@ typedef struct enum { MERam, MERpm, MER24 }; /* Information passed to and from the parser. */ -struct parser_control +typedef struct { /* The input string remaining to be parsed. */ const char *input; @@ -119,7 +127,7 @@ struct parser_control int meridian; /* Gregorian year, month, day, hour, minutes, and seconds. */ - int year; + textint year; int month; int day; int hour; @@ -144,12 +152,11 @@ struct parser_control /* Table of local time zone abbrevations, terminated by a null entry. */ table local_time_zone_table[3]; -}; +} parser_control; -#define PC (* (struct parser_control *) parm) +#define PC (* (parser_control *) parm) #define YYLEX_PARAM parm #define YYPARSE_PARAM parm -#define YYSTYPE int static int yyerror (); static int yylex (); @@ -161,10 +168,21 @@ static int yylex (); /* This grammar has 13 shift/reduce conflicts. */ %expect 13 + +%union +{ + int intval; + textint textintval; +} + +%token tAGO tDST -%token tAGO tDAY tDAY_UNIT tDAYZONE tDST tHOUR_UNIT tID -%token tLOCAL_ZONE tMERIDIAN tMINUTE_UNIT tMONTH tMONTH_UNIT -%token tSEC_UNIT tSNUMBER tUNUMBER tYEAR_UNIT tZONE +%token tDAY tDAY_UNIT tDAYZONE tHOUR_UNIT tLOCAL_ZONE tMERIDIAN +%token tMINUTE_UNIT tMONTH tMONTH_UNIT tSEC_UNIT tYEAR_UNIT tZONE + +%token tSNUMBER tUNUMBER + +%type o_merid %% @@ -192,41 +210,41 @@ item: time: tUNUMBER tMERIDIAN { - PC.hour = $1; + PC.hour = $1.value; PC.minutes = 0; PC.seconds = 0; PC.meridian = $2; } | tUNUMBER ':' tUNUMBER o_merid { - PC.hour = $1; - PC.minutes = $3; + PC.hour = $1.value; + PC.minutes = $3.value; PC.seconds = 0; PC.meridian = $4; } | tUNUMBER ':' tUNUMBER tSNUMBER { - PC.hour = $1; - PC.minutes = $3; + PC.hour = $1.value; + PC.minutes = $3.value; PC.meridian = MER24; PC.zones_seen++; - PC.time_zone = $4 % 100 + ($4 / 100) * 60; + PC.time_zone = $4.value % 100 + ($4.value / 100) * 60; } | tUNUMBER ':' tUNUMBER ':' tUNUMBER o_merid { - PC.hour = $1; - PC.minutes = $3; - PC.seconds = $5; + PC.hour = $1.value; + PC.minutes = $3.value; + PC.seconds = $5.value; PC.meridian = $6; } | tUNUMBER ':' tUNUMBER ':' tUNUMBER tSNUMBER { - PC.hour = $1; - PC.minutes = $3; - PC.seconds = $5; + PC.hour = $1.value; + PC.minutes = $3.value; + PC.seconds = $5.value; PC.meridian = MER24; PC.zones_seen++; - PC.time_zone = $6 % 100 + ($6 / 100) * 60; + PC.time_zone = $6.value % 100 + ($6.value / 100) * 60; } ; @@ -259,7 +277,7 @@ day: } | tUNUMBER tDAY { - PC.day_ordinal = $1; + PC.day_ordinal = $1.value; PC.day_number = $2; } ; @@ -267,25 +285,26 @@ day: date: tUNUMBER '/' tUNUMBER { - PC.month = $1; - PC.day = $3; + PC.month = $1.value; + PC.day = $3.value; } | tUNUMBER '/' tUNUMBER '/' tUNUMBER { - /* Interpret as YYYY/MM/DD if 1000 <= $1, otherwise as MM/DD/YY. + /* Interpret as YYYY/MM/DD if the first value has 4 or more digits, + otherwise as MM/DD/YY. The goal in recognizing YYYY/MM/DD is solely to support legacy machine-generated dates like those in an RCS log listing. If you want portability, use the ISO 8601 format. */ - if (1000 <= $1) + if (4 <= $1.digits) { PC.year = $1; - PC.month = $3; - PC.day = $5; + PC.month = $3.value; + PC.day = $5.value; } else { - PC.month = $1; - PC.day = $3; + PC.month = $1.value; + PC.day = $3.value; PC.year = $5; } } @@ -293,36 +312,37 @@ date: { /* ISO 8601 format. YYYY-MM-DD. */ PC.year = $1; - PC.month = -$2; - PC.day = -$3; + PC.month = -$2.value; + PC.day = -$3.value; } | tUNUMBER tMONTH tSNUMBER { /* e.g. 17-JUN-1992. */ - PC.day = $1; + PC.day = $1.value; PC.month = $2; - PC.year = -$3; + PC.year.value = -$3.value; + PC.year.digits = $3.digits; } | tMONTH tUNUMBER { PC.month = $1; - PC.day = $2; + PC.day = $2.value; } | tMONTH tUNUMBER ',' tUNUMBER { PC.month = $1; - PC.day = $2; + PC.day = $2.value; PC.year = $4; } | tUNUMBER tMONTH { + PC.day = $1.value; PC.month = $2; - PC.day = $1; } | tUNUMBER tMONTH tUNUMBER { + PC.day = $1.value; PC.month = $2; - PC.day = $1; PC.year = $3; } ; @@ -342,39 +362,39 @@ rel: relunit: tUNUMBER tYEAR_UNIT - { PC.rel_year += $1 * $2; } + { PC.rel_year += $1.value * $2; } | tSNUMBER tYEAR_UNIT - { PC.rel_year += $1 * $2; } + { PC.rel_year += $1.value * $2; } | tYEAR_UNIT { PC.rel_year += $1; } | tUNUMBER tMONTH_UNIT - { PC.rel_month += $1 * $2; } + { PC.rel_month += $1.value * $2; } | tSNUMBER tMONTH_UNIT - { PC.rel_month += $1 * $2; } + { PC.rel_month += $1.value * $2; } | tMONTH_UNIT { PC.rel_month += $1; } | tUNUMBER tDAY_UNIT - { PC.rel_day += $1 * $2; } + { PC.rel_day += $1.value * $2; } | tSNUMBER tDAY_UNIT - { PC.rel_day += $1 * $2; } + { PC.rel_day += $1.value * $2; } | tDAY_UNIT - { PC.rel_day += $1; } + { PC.rel_day += $1 } | tUNUMBER tHOUR_UNIT - { PC.rel_hour += $1 * $2; } + { PC.rel_hour += $1.value * $2; } | tSNUMBER tHOUR_UNIT - { PC.rel_hour += $1 * $2; } + { PC.rel_hour += $1.value * $2; } | tHOUR_UNIT - { PC.rel_hour += $1; } + { PC.rel_hour += $1 } | tUNUMBER tMINUTE_UNIT - { PC.rel_minutes += $1 * $2; } + { PC.rel_minutes += $1.value * $2; } | tSNUMBER tMINUTE_UNIT - { PC.rel_minutes += $1 * $2; } + { PC.rel_minutes += $1.value * $2; } | tMINUTE_UNIT - { PC.rel_minutes += $1; } + { PC.rel_minutes += $1 } | tUNUMBER tSEC_UNIT - { PC.rel_seconds += $1 * $2; } + { PC.rel_seconds += $1.value * $2; } | tSNUMBER tSEC_UNIT - { PC.rel_seconds += $1 * $2; } + { PC.rel_seconds += $1.value * $2; } | tSEC_UNIT { PC.rel_seconds += $1; } ; @@ -382,29 +402,31 @@ relunit: number: tUNUMBER { - if (PC.dates_seen && ! PC.rels_seen && (PC.times_seen || 100 <= $1)) + if (PC.dates_seen + && ! PC.rels_seen && (PC.times_seen || 2 < $1.digits)) PC.year = $1; else { - if (10000 < $1) + if (4 < $1.digits) { PC.dates_seen++; - PC.day = $1 % 100; - PC.month = ($1 / 100) % 100; - PC.year = $1 / 10000; + PC.day = $1.value % 100; + PC.month = ($1.value / 100) % 100; + PC.year.value = $1.value / 10000; + PC.year.digits = $1.digits - 4; } else { PC.times_seen++; - if ($1 < 100) + if ($1.digits <= 2) { - PC.hour = $1; + PC.hour = $1.value; PC.minutes = 0; } else { - PC.hour = $1 / 100; - PC.minutes = $1 % 100; + PC.hour = $1.value / 100; + PC.minutes = $1.value % 100; } PC.seconds = 0; PC.meridian = MER24; @@ -632,23 +654,23 @@ to_hour (int hours, int meridian) } static int -to_year (int year) +to_year (textint textyear) { + int year = textyear.value; + if (year < 0) year = -year; /* XPG4 suggests that years 00-68 map to 2000-2068, and years 69-99 map to 1969-1999. */ - if (year < 69) - year += 2000; - else if (year < 100) - year += 1900; + if (textyear.digits == 2) + year += year < 69 ? 2000 : 1900; return year; } static table const * -lookup_zone (struct parser_control const *pc, char const *name) +lookup_zone (parser_control const *pc, char const *name) { table const *tp; @@ -692,7 +714,7 @@ tm_diff (struct tm const *a, struct tm const *b) #endif /* ! HAVE_TM_GMTOFF */ static table const * -lookup_word (struct parser_control const *pc, char *word) +lookup_word (parser_control const *pc, char *word) { char *p; char *q; @@ -761,7 +783,7 @@ lookup_word (struct parser_control const *pc, char *word) } static int -yylex (YYSTYPE *lvalp, struct parser_control *pc) +yylex (YYSTYPE *lvalp, parser_control *pc) { unsigned char c; int count; @@ -773,21 +795,30 @@ yylex (YYSTYPE *lvalp, struct parser_control *pc) if (ISDIGIT (c) || c == '-' || c == '+') { + char const *p; int sign; + int value; if (c == '-' || c == '+') { sign = c == '-' ? -1 : 1; - if (! ISDIGIT (*++pc->input)) + c = *++pc->input; + if (! ISDIGIT (c)) /* skip the '-' sign */ continue; } else sign = 0; - for (*lvalp = 0; ISDIGIT (c = *pc->input++);) - *lvalp = 10 * *lvalp + (c - '0'); - pc->input--; - if (sign < 0) - *lvalp = - *lvalp; + p = pc->input; + value = 0; + do + { + value = 10 * value + c - '0'; + c = *++p; + } + while (ISDIGIT (c)); + lvalp->textintval.value = sign < 0 ? -value : value; + lvalp->textintval.digits = p - pc->input; + pc->input = p; return sign ? tSNUMBER : tUNUMBER; } @@ -808,8 +839,8 @@ yylex (YYSTYPE *lvalp, struct parser_control *pc) *p = '\0'; tp = lookup_word (pc, buff); if (! tp) - return tID; - *lvalp = tp->value; + return '?'; + lvalp->intval = tp->value; return tp->type; } @@ -848,13 +879,14 @@ get_date (const char *p, const time_t *now) struct tm *tmp = localtime (&Start); struct tm tm; struct tm tm0; - struct parser_control pc; + parser_control pc; if (! tmp) return -1; pc.input = p; - pc.year = tmp->tm_year + TM_YEAR_BASE; + pc.year.value = tmp->tm_year + TM_YEAR_BASE; + pc.year.digits = 4; pc.month = tmp->tm_mon + 1; pc.day = tmp->tm_mday; pc.hour = tmp->tm_hour;