diff options
Diffstat (limited to 'lib/parse-datetime.y')
| -rw-r--r-- | lib/parse-datetime.y | 2442 |
1 files changed, 2442 insertions, 0 deletions
diff --git a/lib/parse-datetime.y b/lib/parse-datetime.y new file mode 100644 index 0000000..9fc14c9 --- /dev/null +++ b/lib/parse-datetime.y @@ -0,0 +1,2442 @@ +%{ +/* Parse a string into an internal timestamp. + + Copyright (C) 1999-2000, 2002-2022 Free Software Foundation, Inc. + + This program 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. + + This program 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 this program. If not, see <https://www.gnu.org/licenses/>. */ + +/* 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. + + Modified by Assaf Gordon <assafgordon@gmail.com> in 2016 to add + debug output. + + Modified by Paul Eggert <eggert@twinsun.com> in 1999 to do the + right thing about local DST. Also modified by Paul Eggert + <eggert@cs.ucla.edu> in 2004 to support nanosecond-resolution + timestamps, in 2004 to support TZ strings in dates, and in 2017 and 2020 to + check for integer overflow and to support longer-than-'long' + 'time_t' and 'tv_nsec'. */ + +#include <config.h> + +#include "parse-datetime.h" + +#include "idx.h" +#include "intprops.h" +#include "timespec.h" +#include "verify.h" +#include "strftime.h" + +/* There's no need to extend the stack, so there's no need to involve + alloca. */ +#define YYSTACK_USE_ALLOCA 0 + +/* Tell Bison how much stack space is needed. 20 should be plenty for + this grammar, which is not right recursive. Beware setting it too + high, since that might cause problems on machines whose + implementations have lame stack-overflow checking. */ +#define YYMAXDEPTH 20 +#define YYINITDEPTH YYMAXDEPTH + +/* Since the code of parse-datetime.y is not included in the Emacs executable + itself, there is no need to #define static in this file. Even if + the code were included in the Emacs executable, it probably + wouldn't do any harm to #undef it here; this will only cause + problems if we try to write to a static variable, which I don't + think this code needs to do. */ +#ifdef emacs +# undef static +#endif + +#include <inttypes.h> +#include <c-ctype.h> +#include <stdarg.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "gettext.h" + +#define _(str) gettext (str) + +/* Bison's skeleton tests _STDLIB_H, while some stdlib.h headers + use _STDLIB_H_ as witness. Map the latter to the one bison uses. */ +/* FIXME: this is temporary. Remove when we have a mechanism to ensure + that the version we're using is fixed, too. */ +#ifdef _STDLIB_H_ +# undef _STDLIB_H +# define _STDLIB_H 1 +#endif + +/* Shift A right by B bits portably, by dividing A by 2**B and + truncating towards minus infinity. A and B should be free of side + effects, and B should be in the range 0 <= B <= INT_BITS - 2, where + INT_BITS is the number of useful bits in an int. GNU code can + assume that INT_BITS is at least 32. + + ISO C99 says that A >> B is implementation-defined if A < 0. Some + implementations (e.g., UNICOS 9.0 on a Cray Y-MP EL) don't shift + right in the usual way when A < 0, so SHR falls back on division if + ordinary A >> B doesn't seem to be the usual signed shift. */ +#define SHR(a, b) \ + (-1 >> 1 == -1 \ + ? (a) >> (b) \ + : (a) / (1 << (b)) - ((a) % (1 << (b)) < 0)) + +#define HOUR(x) (60 * 60 * (x)) + +#define STREQ(a, b) (strcmp (a, b) == 0) + +/* Verify that time_t is an integer as POSIX requires, and that every + time_t value fits in intmax_t. Please file a bug report if these + assumptions are false on your platform. */ +verify (TYPE_IS_INTEGER (time_t)); +verify (!TYPE_SIGNED (time_t) || INTMAX_MIN <= TYPE_MINIMUM (time_t)); +verify (TYPE_MAXIMUM (time_t) <= INTMAX_MAX); + +/* True if N is out of range for time_t. */ +static bool +time_overflow (intmax_t n) +{ + return ! ((TYPE_SIGNED (time_t) ? TYPE_MINIMUM (time_t) <= n : 0 <= n) + && n <= TYPE_MAXIMUM (time_t)); +} + +/* Convert a possibly-signed character to an unsigned character. This is + a bit safer than casting to unsigned char, since it catches some type + errors that the cast doesn't. */ +static unsigned char to_uchar (char ch) { return ch; } + +static void _GL_ATTRIBUTE_FORMAT ((__printf__, 1, 2)) +dbg_printf (char const *msg, ...) +{ + va_list args; + /* TODO: use gnulib's 'program_name' instead? */ + fputs ("date: ", stderr); + + va_start (args, msg); + vfprintf (stderr, msg, args); + va_end (args); +} + + +/* An integer value, and the number of digits in its textual + representation. */ +typedef struct +{ + bool negative; + intmax_t value; + idx_t digits; +} textint; + +/* An entry in the lexical lookup table. */ +typedef struct +{ + char const *name; + int type; + int value; +} table; + +/* Meridian: am, pm, or 24-hour style. */ +enum { MERam, MERpm, MER24 }; + +/* A reasonable upper bound for the buffer used in debug output. */ +enum { DBGBUFSIZE = 100 }; + +enum { BILLION = 1000000000, LOG10_BILLION = 9 }; + +/* Relative times. */ +typedef struct +{ + /* Relative year, month, day, hour, minutes, seconds, and nanoseconds. */ + intmax_t year; + intmax_t month; + intmax_t day; + intmax_t hour; + intmax_t minutes; + intmax_t seconds; + int ns; +} relative_time; + +#if HAVE_COMPOUND_LITERALS +# define RELATIVE_TIME_0 ((relative_time) { 0, 0, 0, 0, 0, 0, 0 }) +#else +static relative_time const RELATIVE_TIME_0; +#endif + +/* Information passed to and from the parser. */ +typedef struct +{ + /* The input string remaining to be parsed. */ + const char *input; + + /* N, if this is the Nth Tuesday. */ + intmax_t day_ordinal; + + /* Day of week; Sunday is 0. */ + int day_number; + + /* tm_isdst flag for the local zone. */ + int local_isdst; + + /* Time zone, in seconds east of UT. */ + int time_zone; + + /* Style used for time. */ + int meridian; + + /* Gregorian year, month, day, hour, minutes, seconds, and nanoseconds. */ + textint year; + intmax_t month; + intmax_t day; + intmax_t hour; + intmax_t minutes; + struct timespec seconds; /* includes nanoseconds */ + + /* Relative year, month, day, hour, minutes, seconds, and nanoseconds. */ + relative_time rel; + + /* Presence or counts of nonterminals of various flavors parsed so far. */ + bool timespec_seen; + bool rels_seen; + idx_t dates_seen; + idx_t days_seen; + idx_t local_zones_seen; + idx_t dsts_seen; + idx_t times_seen; + idx_t zones_seen; + bool year_seen; + +#ifdef GNULIB_PARSE_DATETIME2 + /* Print debugging output to stderr. */ + bool parse_datetime_debug; +#endif + + /* Which of the 'seen' parts have been printed when debugging. */ + bool debug_dates_seen; + bool debug_days_seen; + bool debug_local_zones_seen; + bool debug_times_seen; + bool debug_zones_seen; + bool debug_year_seen; + + /* The user specified explicit ordinal day value. */ + bool debug_ordinal_day_seen; + + /* Table of local time zone abbreviations, terminated by a null entry. */ + table local_time_zone_table[3]; +} parser_control; + +static bool +debugging (parser_control const *pc) +{ +#ifdef GNULIB_PARSE_DATETIME2 + return pc->parse_datetime_debug; +#else + return false; +#endif +} + +union YYSTYPE; +static int yylex (union YYSTYPE *, parser_control *); +static int yyerror (parser_control const *, char const *); +static bool time_zone_hhmm (parser_control *, textint, intmax_t); + +/* Extract into *PC any date and time info from a string of digits + of the form e.g., YYYYMMDD, YYMMDD, HHMM, HH (and sometimes YYY, + YYYY, ...). */ +static void +digits_to_date_time (parser_control *pc, textint text_int) +{ + if (pc->dates_seen && ! pc->year.digits + && ! pc->rels_seen && (pc->times_seen || 2 < text_int.digits)) + { + pc->year_seen = true; + pc->year = text_int; + } + else + { + if (4 < text_int.digits) + { + pc->dates_seen++; + pc->day = text_int.value % 100; + pc->month = (text_int.value / 100) % 100; + pc->year.value = text_int.value / 10000; + pc->year.digits = text_int.digits - 4; + } + else + { + pc->times_seen++; + if (text_int.digits <= 2) + { + pc->hour = text_int.value; + pc->minutes = 0; + } + else + { + pc->hour = text_int.value / 100; + pc->minutes = text_int.value % 100; + } + pc->seconds.tv_sec = 0; + pc->seconds.tv_nsec = 0; + pc->meridian = MER24; + } + } +} + +/* Increment PC->rel by FACTOR * REL (FACTOR is 1 or -1). Return true + if successful, false if an overflow occurred. */ +static bool +apply_relative_time (parser_control *pc, relative_time rel, int factor) +{ + if (factor < 0 + ? (INT_SUBTRACT_WRAPV (pc->rel.ns, rel.ns, &pc->rel.ns) + | INT_SUBTRACT_WRAPV (pc->rel.seconds, rel.seconds, &pc->rel.seconds) + | INT_SUBTRACT_WRAPV (pc->rel.minutes, rel.minutes, &pc->rel.minutes) + | INT_SUBTRACT_WRAPV (pc->rel.hour, rel.hour, &pc->rel.hour) + | INT_SUBTRACT_WRAPV (pc->rel.day, rel.day, &pc->rel.day) + | INT_SUBTRACT_WRAPV (pc->rel.month, rel.month, &pc->rel.month) + | INT_SUBTRACT_WRAPV (pc->rel.year, rel.year, &pc->rel.year)) + : (INT_ADD_WRAPV (pc->rel.ns, rel.ns, &pc->rel.ns) + | INT_ADD_WRAPV (pc->rel.seconds, rel.seconds, &pc->rel.seconds) + | INT_ADD_WRAPV (pc->rel.minutes, rel.minutes, &pc->rel.minutes) + | INT_ADD_WRAPV (pc->rel.hour, rel.hour, &pc->rel.hour) + | INT_ADD_WRAPV (pc->rel.day, rel.day, &pc->rel.day) + | INT_ADD_WRAPV (pc->rel.month, rel.month, &pc->rel.month) + | INT_ADD_WRAPV (pc->rel.year, rel.year, &pc->rel.year))) + return false; + pc->rels_seen = true; + return true; +} + +/* Set PC-> hour, minutes, seconds and nanoseconds members from arguments. */ +static void +set_hhmmss (parser_control *pc, intmax_t hour, intmax_t minutes, + time_t sec, int nsec) +{ + pc->hour = hour; + pc->minutes = minutes; + pc->seconds.tv_sec = sec; + pc->seconds.tv_nsec = nsec; +} + +/* Return a textual representation of the day ordinal/number values + in the parser_control struct (e.g., "last wed", "this tues", "thu"). */ +static const char * +str_days (parser_control *pc, char *buffer, int n) +{ + /* TODO: use relative_time_table for reverse lookup. */ + static char const ordinal_values[][11] = { + "last", + "this", + "next/first", + "(SECOND)", /* SECOND is commented out in relative_time_table. */ + "third", + "fourth", + "fifth", + "sixth", + "seventh", + "eight", + "ninth", + "tenth", + "eleventh", + "twelfth" + }; + + static char const days_values[][4] = { + "Sun", + "Mon", + "Tue", + "Wed", + "Thu", + "Fri", + "Sat" + }; + + int len; + + /* Don't add an ordinal prefix if the user didn't specify it + (e.g., "this wed" vs "wed"). */ + if (pc->debug_ordinal_day_seen) + { + /* Use word description if possible (e.g., -1 = last, 3 = third). */ + len = (-1 <= pc->day_ordinal && pc->day_ordinal <= 12 + ? snprintf (buffer, n, "%s", ordinal_values[pc->day_ordinal + 1]) + : snprintf (buffer, n, "%"PRIdMAX, pc->day_ordinal)); + } + else + { + buffer[0] = '\0'; + len = 0; + } + + /* Add the day name */ + if (0 <= pc->day_number && pc->day_number <= 6 && 0 <= len && len < n) + snprintf (buffer + len, n - len, &" %s"[len == 0], + days_values[pc->day_number]); + else + { + /* invalid day_number value - should never happen */ + } + return buffer; +} + +/* Convert a time zone to its string representation. */ + +enum { TIME_ZONE_BUFSIZE = INT_STRLEN_BOUND (intmax_t) + sizeof ":MM:SS" } ; + +static char const * +time_zone_str (int time_zone, char time_zone_buf[TIME_ZONE_BUFSIZE]) +{ + char *p = time_zone_buf; + char sign = time_zone < 0 ? '-' : '+'; + int hour = abs (time_zone / (60 * 60)); + p += sprintf (time_zone_buf, "%c%02d", sign, hour); + int offset_from_hour = abs (time_zone % (60 * 60)); + if (offset_from_hour != 0) + { + int mm = offset_from_hour / 60; + int ss = offset_from_hour % 60; + *p++ = ':'; + *p++ = '0' + mm / 10; + *p++ = '0' + mm % 10; + if (ss) + { + *p++ = ':'; + *p++ = '0' + ss / 10; + *p++ = '0' + ss % 10; + } + *p = '\0'; + } + return time_zone_buf; +} + +/* debugging: print the current time in the parser_control structure. + The parser will increment "*_seen" members for those which were parsed. + This function will print only newly seen parts. */ +static void +debug_print_current_time (char const *item, parser_control *pc) +{ + bool space = false; + + if (!debugging (pc)) + return; + + /* no newline, more items printed below */ + dbg_printf (_("parsed %s part: "), item); + + if (pc->dates_seen && !pc->debug_dates_seen) + { + /*TODO: use pc->year.negative? */ + fprintf (stderr, "(Y-M-D) %04"PRIdMAX"-%02"PRIdMAX"-%02"PRIdMAX, + pc->year.value, pc->month, pc->day); + pc->debug_dates_seen = true; + space = true; + } + + if (pc->year_seen != pc->debug_year_seen) + { + if (space) + fputc (' ', stderr); + fprintf (stderr, _("year: %04"PRIdMAX), pc->year.value); + + pc->debug_year_seen = pc->year_seen; + space = true; + } + + if (pc->times_seen && !pc->debug_times_seen) + { + intmax_t sec = pc->seconds.tv_sec; + fprintf (stderr, &" %02"PRIdMAX":%02"PRIdMAX":%02"PRIdMAX[!space], + pc->hour, pc->minutes, sec); + if (pc->seconds.tv_nsec != 0) + { + int nsec = pc->seconds.tv_nsec; + fprintf (stderr, ".%09d", nsec); + } + if (pc->meridian == MERpm) + fputs ("pm", stderr); + + pc->debug_times_seen = true; + space = true; + } + + if (pc->days_seen && !pc->debug_days_seen) + { + if (space) + fputc (' ', stderr); + char tmp[DBGBUFSIZE]; + fprintf (stderr, _("%s (day ordinal=%"PRIdMAX" number=%d)"), + str_days (pc, tmp, sizeof tmp), + pc->day_ordinal, pc->day_number); + pc->debug_days_seen = true; + space = true; + } + + /* local zone strings only change the DST settings, + not the timezone value. If seen, inform about the DST. */ + if (pc->local_zones_seen && !pc->debug_local_zones_seen) + { + fprintf (stderr, &" isdst=%d%s"[!space], + pc->local_isdst, pc->dsts_seen ? " DST" : ""); + pc->debug_local_zones_seen = true; + space = true; + } + + if (pc->zones_seen && !pc->debug_zones_seen) + { + char time_zone_buf[TIME_ZONE_BUFSIZE]; + fprintf (stderr, &" UTC%s"[!space], + time_zone_str (pc->time_zone, time_zone_buf)); + pc->debug_zones_seen = true; + space = true; + } + + if (pc->timespec_seen) + { + intmax_t sec = pc->seconds.tv_sec; + if (space) + fputc (' ', stderr); + fprintf (stderr, _("number of seconds: %"PRIdMAX), sec); + } + + fputc ('\n', stderr); +} + +/* Debugging: print the current relative values. */ + +static bool +print_rel_part (bool space, intmax_t val, char const *name) +{ + if (val == 0) + return space; + fprintf (stderr, &" %+"PRIdMAX" %s"[!space], val, name); + return true; +} + +static void +debug_print_relative_time (char const *item, parser_control const *pc) +{ + bool space = false; + + if (!debugging (pc)) + return; + + /* no newline, more items printed below */ + dbg_printf (_("parsed %s part: "), item); + + if (pc->rel.year == 0 && pc->rel.month == 0 && pc->rel.day == 0 + && pc->rel.hour == 0 && pc->rel.minutes == 0 && pc->rel.seconds == 0 + && pc->rel.ns == 0) + { + /* Special case: relative time of this/today/now */ + fputs (_("today/this/now\n"), stderr); + return; + } + + space = print_rel_part (space, pc->rel.year, "year(s)"); + space = print_rel_part (space, pc->rel.month, "month(s)"); + space = print_rel_part (space, pc->rel.day, "day(s)"); + space = print_rel_part (space, pc->rel.hour, "hour(s)"); + space = print_rel_part (space, pc->rel.minutes, "minutes"); + space = print_rel_part (space, pc->rel.seconds, "seconds"); + print_rel_part (space, pc->rel.ns, "nanoseconds"); + + fputc ('\n', stderr); +} + + + +%} + +/* We want a reentrant parser, even if the TZ manipulation and the calls to + localtime and gmtime are not reentrant. */ +%define api.pure +%parse-param { parser_control *pc } +%lex-param { parser_control *pc } + +/* This grammar has 31 shift/reduce conflicts. */ +%expect 31 + +%union +{ + intmax_t intval; + textint textintval; + struct timespec timespec; + relative_time rel; +} + +%token <intval> tAGO +%token tDST + +%token tYEAR_UNIT tMONTH_UNIT tHOUR_UNIT tMINUTE_UNIT tSEC_UNIT +%token <intval> tDAY_UNIT tDAY_SHIFT + +%token <intval> tDAY tDAYZONE tLOCAL_ZONE tMERIDIAN +%token <intval> tMONTH tORDINAL tZONE + +%token <textintval> tSNUMBER tUNUMBER +%token <timespec> tSDECIMAL_NUMBER tUDECIMAL_NUMBER + +%type <intval> o_colon_minutes +%type <timespec> seconds signed_seconds unsigned_seconds + +%type <rel> relunit relunit_snumber dayshift + +%% + +spec: + timespec + | items + ; + +timespec: + '@' seconds + { + pc->seconds = $2; + pc->timespec_seen = true; + debug_print_current_time (_("number of seconds"), pc); + } + ; + +items: + /* empty */ + | items item + ; + +item: + datetime + { + pc->times_seen++; pc->dates_seen++; + debug_print_current_time (_("datetime"), pc); + } + | time + { + pc->times_seen++; + debug_print_current_time (_("time"), pc); + } + | local_zone + { + pc->local_zones_seen++; + debug_print_current_time (_("local_zone"), pc); + } + | zone + { + pc->zones_seen++; + debug_print_current_time (_("zone"), pc); + } + | date + { + pc->dates_seen++; + debug_print_current_time (_("date"), pc); + } + | day + { + pc->days_seen++; + debug_print_current_time (_("day"), pc); + } + | rel + { + debug_print_relative_time (_("relative"), pc); + } + | number + { + debug_print_current_time (_("number"), pc); + } + | hybrid + { + debug_print_relative_time (_("hybrid"), pc); + } + ; + +datetime: + iso_8601_datetime + ; + +iso_8601_datetime: + iso_8601_date 'T' iso_8601_time + ; + +time: + tUNUMBER tMERIDIAN + { + set_hhmmss (pc, $1.value, 0, 0, 0); + pc->meridian = $2; + } + | tUNUMBER ':' tUNUMBER tMERIDIAN + { + set_hhmmss (pc, $1.value, $3.value, 0, 0); + pc->meridian = $4; + } + | tUNUMBER ':' tUNUMBER ':' unsigned_seconds tMERIDIAN + { + set_hhmmss (pc, $1.value, $3.value, $5.tv_sec, $5.tv_nsec); + pc->meridian = $6; + } + | iso_8601_time + ; + +iso_8601_time: + tUNUMBER zone_offset + { + set_hhmmss (pc, $1.value, 0, 0, 0); + pc->meridian = MER24; + } + | tUNUMBER ':' tUNUMBER o_zone_offset + { + set_hhmmss (pc, $1.value, $3.value, 0, 0); + pc->meridian = MER24; + } + | tUNUMBER ':' tUNUMBER ':' unsigned_seconds o_zone_offset + { + set_hhmmss (pc, $1.value, $3.value, $5.tv_sec, $5.tv_nsec); + pc->meridian = MER24; + } + ; + +o_zone_offset: + /* empty */ + | zone_offset + ; + +zone_offset: + tSNUMBER o_colon_minutes + { + pc->zones_seen++; + if (! time_zone_hhmm (pc, $1, $2)) YYABORT; + } + ; + +/* Local zone strings affect only the DST setting, and take effect + only if the current TZ setting is relevant. + + Example 1: + 'EEST' is parsed as tLOCAL_ZONE, as it relates to the effective TZ: + TZ='Europe/Helsinki' date -d '2016-06-30 EEST' + + Example 2: + 'EEST' is parsed as tDAYZONE: + TZ='Asia/Tokyo' date -d '2016-06-30 EEST' + + This is implemented by probing the next three calendar quarters + of the effective timezone and looking for DST changes - + if found, the timezone name (EEST) is inserted into + the lexical lookup table with type tLOCAL_ZONE. + (Search for 'quarter' comment in 'parse_datetime2'.) +*/ +local_zone: + tLOCAL_ZONE + { pc->local_isdst = $1; } + | tLOCAL_ZONE tDST + { + pc->local_isdst = 1; + pc->dsts_seen++; + } + ; + +/* Note 'T' is a special case, as it is used as the separator in ISO + 8601 date and time of day representation. */ +zone: + tZONE + { pc->time_zone = $1; } + | 'T' + { pc->time_zone = -HOUR (7); } + | tZONE relunit_snumber + { pc->time_zone = $1; + if (! apply_relative_time (pc, $2, 1)) YYABORT; + debug_print_relative_time (_("relative"), pc); + } + | 'T' relunit_snumber + { pc->time_zone = -HOUR (7); + if (! apply_relative_time (pc, $2, 1)) YYABORT; + debug_print_relative_time (_("relative"), pc); + } + | tZONE tSNUMBER o_colon_minutes + { if (! time_zone_hhmm (pc, $2, $3)) YYABORT; + if (INT_ADD_WRAPV (pc->time_zone, $1, &pc->time_zone)) YYABORT; } + | tDAYZONE + { pc->time_zone = $1 + 60 * 60; } + | tZONE tDST + { pc->time_zone = $1 + 60 * 60; } + ; + +day: + tDAY + { + pc->day_ordinal = 0; + pc->day_number = $1; + } + | tDAY ',' + { + pc->day_ordinal = 0; + pc->day_number = $1; + } + | tORDINAL tDAY + { + pc->day_ordinal = $1; + pc->day_number = $2; + pc->debug_ordinal_day_seen = true; + } + | tUNUMBER tDAY + { + pc->day_ordinal = $1.value; + pc->day_number = $2; + pc->debug_ordinal_day_seen = true; + } + ; + +date: + tUNUMBER '/' tUNUMBER + { + pc->month = $1.value; + pc->day = $3.value; + } + | tUNUMBER '/' tUNUMBER '/' tUNUMBER + { + /* 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 (4 <= $1.digits) + { + if (debugging (pc)) + { + intmax_t digits = $1.digits; + dbg_printf (_("warning: value %"PRIdMAX" has %"PRIdMAX" digits. " + "Assuming YYYY/MM/DD\n"), + $1.value, digits); + } + + pc->year = $1; + pc->month = $3.value; + pc->day = $5.value; + } + else + { + if (debugging (pc)) + dbg_printf (_("warning: value %"PRIdMAX" has less than 4 digits. " + "Assuming MM/DD/YY[YY]\n"), + $1.value); + + pc->month = $1.value; + pc->day = $3.value; + pc->year = $5; + } + } + | tUNUMBER tMONTH tSNUMBER + { + /* E.g., 17-JUN-1992. */ + pc->day = $1.value; + pc->month = $2; + if (INT_SUBTRACT_WRAPV (0, $3.value, &pc->year.value)) YYABORT; + pc->year.digits = $3.digits; + } + | tMONTH tSNUMBER tSNUMBER + { + /* E.g., JUN-17-1992. */ + pc->month = $1; + if (INT_SUBTRACT_WRAPV (0, $2.value, &pc->day)) YYABORT; + if (INT_SUBTRACT_WRAPV (0, $3.value, &pc->year.value)) YYABORT; + pc->year.digits = $3.digits; + } + | tMONTH tUNUMBER + { + pc->month = $1; + pc->day = $2.value; + } + | tMONTH tUNUMBER ',' tUNUMBER + { + pc->month = $1; + pc->day = $2.value; + pc->year = $4; + } + | tUNUMBER tMONTH + { + pc->day = $1.value; + pc->month = $2; + } + | tUNUMBER tMONTH tUNUMBER + { + pc->day = $1.value; + pc->month = $2; + pc->year = $3; + } + | iso_8601_date + ; + +iso_8601_date: + tUNUMBER tSNUMBER tSNUMBER + { + /* ISO 8601 format. YYYY-MM-DD. */ + pc->year = $1; + if (INT_SUBTRACT_WRAPV (0, $2.value, &pc->month)) YYABORT; + if (INT_SUBTRACT_WRAPV (0, $3.value, &pc->day)) YYABORT; + } + ; + +rel: + relunit tAGO + { if (! apply_relative_time (pc, $1, $2)) YYABORT; } + | relunit + { if (! apply_relative_time (pc, $1, 1)) YYABORT; } + | dayshift + { if (! apply_relative_time (pc, $1, 1)) YYABORT; } + ; + +relunit: + tORDINAL tYEAR_UNIT + { $$ = RELATIVE_TIME_0; $$.year = $1; } + | tUNUMBER tYEAR_UNIT + { $$ = RELATIVE_TIME_0; $$.year = $1.value; } + | tYEAR_UNIT + { $$ = RELATIVE_TIME_0; $$.year = 1; } + | tORDINAL tMONTH_UNIT + { $$ = RELATIVE_TIME_0; $$.month = $1; } + | tUNUMBER tMONTH_UNIT + { $$ = RELATIVE_TIME_0; $$.month = $1.value; } + | tMONTH_UNIT + { $$ = RELATIVE_TIME_0; $$.month = 1; } + | tORDINAL tDAY_UNIT + { $$ = RELATIVE_TIME_0; + if (INT_MULTIPLY_WRAPV ($1, $2, &$$.day)) YYABORT; } + | tUNUMBER tDAY_UNIT + { $$ = RELATIVE_TIME_0; + if (INT_MULTIPLY_WRAPV ($1.value, $2, &$$.day)) YYABORT; } + | tDAY_UNIT + { $$ = RELATIVE_TIME_0; $$.day = $1; } + | tORDINAL tHOUR_UNIT + { $$ = RELATIVE_TIME_0; $$.hour = $1; } + | tUNUMBER tHOUR_UNIT + { $$ = RELATIVE_TIME_0; $$.hour = $1.value; } + | tHOUR_UNIT + { $$ = RELATIVE_TIME_0; $$.hour = 1; } + | tORDINAL tMINUTE_UNIT + { $$ = RELATIVE_TIME_0; $$.minutes = $1; } + | tUNUMBER tMINUTE_UNIT + { $$ = RELATIVE_TIME_0; $$.minutes = $1.value; } + | tMINUTE_UNIT + { $$ = RELATIVE_TIME_0; $$.minutes = 1; } + | tORDINAL tSEC_UNIT + { $$ = RELATIVE_TIME_0; $$.seconds = $1; } + | tUNUMBER tSEC_UNIT + { $$ = RELATIVE_TIME_0; $$.seconds = $1.value; } + | tSDECIMAL_NUMBER tSEC_UNIT + { $$ = RELATIVE_TIME_0; $$.seconds = $1.tv_sec; $$.ns = $1.tv_nsec; } + | tUDECIMAL_NUMBER tSEC_UNIT + { $$ = RELATIVE_TIME_0; $$.seconds = $1.tv_sec; $$.ns = $1.tv_nsec; } + | tSEC_UNIT + { $$ = RELATIVE_TIME_0; $$.seconds = 1; } + | relunit_snumber + ; + +relunit_snumber: + tSNUMBER tYEAR_UNIT + { $$ = RELATIVE_TIME_0; $$.year = $1.value; } + | tSNUMBER tMONTH_UNIT + { $$ = RELATIVE_TIME_0; $$.month = $1.value; } + | tSNUMBER tDAY_UNIT + { $$ = RELATIVE_TIME_0; + if (INT_MULTIPLY_WRAPV ($1.value, $2, &$$.day)) YYABORT; } + | tSNUMBER tHOUR_UNIT + { $$ = RELATIVE_TIME_0; $$.hour = $1.value; } + | tSNUMBER tMINUTE_UNIT + { $$ = RELATIVE_TIME_0; $$.minutes = $1.value; } + | tSNUMBER tSEC_UNIT + { $$ = RELATIVE_TIME_0; $$.seconds = $1.value; } + ; + +dayshift: + tDAY_SHIFT + { $$ = RELATIVE_TIME_0; $$.day = $1; } + ; + +seconds: signed_seconds | unsigned_seconds; + +signed_seconds: + tSDECIMAL_NUMBER + | tSNUMBER + { if (time_overflow ($1.value)) YYABORT; + $$.tv_sec = $1.value; $$.tv_nsec = 0; } + ; + +unsigned_seconds: + tUDECIMAL_NUMBER + | tUNUMBER + { if (time_overflow ($1.value)) YYABORT; + $$.tv_sec = $1.value; $$.tv_nsec = 0; } + ; + +number: + tUNUMBER + { digits_to_date_time (pc, $1); } + ; + +hybrid: + tUNUMBER relunit_snumber + { + /* Hybrid all-digit and relative offset, so that we accept e.g., + "YYYYMMDD +N days" as well as "YYYYMMDD N days". */ + digits_to_date_time (pc, $1); + if (! apply_relative_time (pc, $2, 1)) YYABORT; + } + ; + +o_colon_minutes: + /* empty */ + { $$ = -1; } + | ':' tUNUMBER + { $$ = $2.value; } + ; + +%% + +static table const meridian_table[] = +{ + { "AM", tMERIDIAN, MERam }, + { "A.M.", tMERIDIAN, MERam }, + { "PM", tMERIDIAN, MERpm }, + { "P.M.", tMERIDIAN, MERpm }, + { NULL, 0, 0 } +}; + +static table const dst_table[] = +{ + { "DST", tDST, 0 } +}; + +static table const month_and_day_table[] = +{ + { "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, 0, 0 } +}; + +static table const time_units_table[] = +{ + { "YEAR", tYEAR_UNIT, 1 }, + { "MONTH", tMONTH_UNIT, 1 }, + { "FORTNIGHT",tDAY_UNIT, 14 }, + { "WEEK", tDAY_UNIT, 7 }, + { "DAY", tDAY_UNIT, 1 }, + { "HOUR", tHOUR_UNIT, 1 }, + { "MINUTE", tMINUTE_UNIT, 1 }, + { "MIN", tMINUTE_UNIT, 1 }, + { "SECOND", tSEC_UNIT, 1 }, + { "SEC", tSEC_UNIT, 1 }, + { NULL, 0, 0 } +}; + +/* Assorted relative-time words. */ +static table const relative_time_table[] = +{ + { "TOMORROW", tDAY_SHIFT, 1 }, + { "YESTERDAY",tDAY_SHIFT, -1 }, + { "TODAY", tDAY_SHIFT, 0 }, + { "NOW", tDAY_SHIFT, 0 }, + { "LAST", tORDINAL, -1 }, + { "THIS", tORDINAL, 0 }, + { "NEXT", tORDINAL, 1 }, + { "FIRST", tORDINAL, 1 }, +/*{ "SECOND", tORDINAL, 2 }, */ + { "THIRD", tORDINAL, 3 }, + { "FOURTH", tORDINAL, 4 }, + { "FIFTH", tORDINAL, 5 }, + { "SIXTH", tORDINAL, 6 }, + { "SEVENTH", tORDINAL, 7 }, + { "EIGHTH", tORDINAL, 8 }, + { "NINTH", tORDINAL, 9 }, + { "TENTH", tORDINAL, 10 }, + { "ELEVENTH", tORDINAL, 11 }, + { "TWELFTH", tORDINAL, 12 }, + { "AGO", tAGO, -1 }, + { "HENCE", tAGO, 1 }, + { NULL, 0, 0 } +}; + +/* The universal time zone table. These labels can be used even for + timestamps that would not otherwise be valid, e.g., GMT timestamps + oin London during summer. */ +static table const universal_time_zone_table[] = +{ + { "GMT", tZONE, HOUR ( 0) }, /* Greenwich Mean */ + { "UT", tZONE, HOUR ( 0) }, /* Universal (Coordinated) */ + { "UTC", tZONE, HOUR ( 0) }, + { NULL, 0, 0 } +}; + +/* The time zone table. This table is necessarily incomplete, as time + zone abbreviations are ambiguous; e.g., Australians interpret "EST" + as Eastern time in Australia, not as US Eastern Standard Time. + You cannot rely on parse_datetime to handle arbitrary time zone + abbreviations; use numeric abbreviations like "-0500" instead. */ +static table const time_zone_table[] = +{ + { "WET", tZONE, HOUR ( 0) }, /* Western European */ + { "WEST", tDAYZONE, HOUR ( 0) }, /* Western European Summer */ + { "BST", tDAYZONE, HOUR ( 0) }, /* British Summer */ + { "ART", tZONE, -HOUR ( 3) }, /* Argentina */ + { "BRT", tZONE, -HOUR ( 3) }, /* Brazil */ + { "BRST", tDAYZONE, -HOUR ( 3) }, /* Brazil Summer */ + { "NST", tZONE, -(HOUR ( 3) + 30 * 60) }, /* Newfoundland Standard */ + { "NDT", tDAYZONE,-(HOUR ( 3) + 30 * 60) }, /* Newfoundland Daylight */ + { "AST", tZONE, -HOUR ( 4) }, /* Atlantic Standard */ + { "ADT", tDAYZONE, -HOUR ( 4) }, /* Atlantic Daylight */ + { "CLT", tZONE, -HOUR ( 4) }, /* Chile */ + { "CLST", tDAYZONE, -HOUR ( 4) }, /* Chile Summer */ + { "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 */ + { "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 */ + { "SST", tZONE, -HOUR (12) }, /* Samoa Standard */ + { "WAT", tZONE, HOUR ( 1) }, /* West Africa */ + { "CET", tZONE, HOUR ( 1) }, /* Central European */ + { "CEST", tDAYZONE, HOUR ( 1) }, /* Central European Summer */ + { "MET", tZONE, HOUR ( 1) }, /* Middle European */ + { "MEZ", tZONE, HOUR ( 1) }, /* Middle European */ + { "MEST", tDAYZONE, HOUR ( 1) }, /* Middle European Summer */ + { "MESZ", tDAYZONE, HOUR ( 1) }, /* Middle European Summer */ + { "EET", tZONE, HOUR ( 2) }, /* Eastern European */ + { "EEST", tDAYZONE, HOUR ( 2) }, /* Eastern European Summer */ + { "CAT", tZONE, HOUR ( 2) }, /* Central Africa */ + { "SAST", tZONE, HOUR ( 2) }, /* South Africa Standard */ + { "EAT", tZONE, HOUR ( 3) }, /* East Africa */ + { "MSK", tZONE, HOUR ( 3) }, /* Moscow */ + { "MSD", tDAYZONE, HOUR ( 3) }, /* Moscow Daylight */ + { "IST", tZONE, (HOUR ( 5) + 30 * 60) }, /* India Standard */ + { "SGT", tZONE, HOUR ( 8) }, /* Singapore */ + { "KST", tZONE, HOUR ( 9) }, /* Korea Standard */ + { "JST", tZONE, HOUR ( 9) }, /* Japan Standard */ + { "GST", tZONE, HOUR (10) }, /* Guam Standard */ + { "NZST", tZONE, HOUR (12) }, /* New Zealand Standard */ + { "NZDT", tDAYZONE, HOUR (12) }, /* New Zealand Daylight */ + { NULL, 0, 0 } +}; + +/* Military time zone table. + + RFC 822 got these backwards, but RFC 5322 makes the incorrect + treatment optional, so do them the right way here. + + Note 'T' is a special case, as it is used as the separator in ISO + 8601 date and time of day representation. */ +static table const military_table[] = +{ + { "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", 'T', 0 }, + { "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, 0, 0 } +}; + + + +/* Convert a time zone expressed as HH:MM into an integer count of + seconds. If MM is negative, then S is of the form HHMM and needs + to be picked apart; otherwise, S is of the form HH. As specified in + https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap08.html#tag_08_03, allow + only valid TZ range, and consider first two digits as hours, if no + minutes specified. Return true if successful. */ + +static bool +time_zone_hhmm (parser_control *pc, textint s, intmax_t mm) +{ + intmax_t n_minutes; + bool overflow = false; + + /* If the length of S is 1 or 2 and no minutes are specified, + interpret it as a number of hours. */ + if (s.digits <= 2 && mm < 0) + s.value *= 100; + + if (mm < 0) + n_minutes = (s.value / 100) * 60 + s.value % 100; + else + { + overflow |= INT_MULTIPLY_WRAPV (s.value, 60, &n_minutes); + overflow |= (s.negative + ? INT_SUBTRACT_WRAPV (n_minutes, mm, &n_minutes) + : INT_ADD_WRAPV (n_minutes, mm, &n_minutes)); + } + + if (overflow || ! (-24 * 60 <= n_minutes && n_minutes <= 24 * 60)) + return false; + pc->time_zone = n_minutes * 60; + return true; +} + +static int +to_hour (intmax_t hours, int meridian) +{ + switch (meridian) + { + default: /* Pacify GCC. */ + case MER24: + return 0 <= hours && hours < 24 ? hours : -1; + case MERam: + return 0 < hours && hours < 12 ? hours : hours == 12 ? 0 : -1; + case MERpm: + return 0 < hours && hours < 12 ? hours + 12 : hours == 12 ? 12 : -1; + } +} + +enum { TM_YEAR_BASE = 1900 }; +enum { TM_YEAR_BUFSIZE = INT_BUFSIZE_BOUND (int) + 1 }; + +/* Convert TM_YEAR, a year minus 1900, to a string that is numerically + correct even if subtracting 1900 would overflow. */ + +static char const * +tm_year_str (int tm_year, char buf[TM_YEAR_BUFSIZE]) +{ + verify (TM_YEAR_BASE % 100 == 0); + sprintf (buf, &"-%02d%02d"[-TM_YEAR_BASE <= tm_year], + abs (tm_year / 100 + TM_YEAR_BASE / 100), + abs (tm_year % 100)); + return buf; +} + +/* Convert a text year number to a year minus 1900, working correctly + even if the input is in the range INT_MAX .. INT_MAX + 1900 - 1. */ + +static bool +to_tm_year (textint textyear, bool debug, int *tm_year) +{ + intmax_t year = textyear.value; + + /* XPG4 suggests that years 00-68 map to 2000-2068, and + years 69-99 map to 1969-1999. */ + if (0 <= year && textyear.digits == 2) + { + year += year < 69 ? 2000 : 1900; + if (debug) + dbg_printf (_("warning: adjusting year value %"PRIdMAX + " to %"PRIdMAX"\n"), + textyear.value, year); + } + + if (year < 0 + ? INT_SUBTRACT_WRAPV (-TM_YEAR_BASE, year, tm_year) + : INT_SUBTRACT_WRAPV (year, TM_YEAR_BASE, tm_year)) + { + if (debug) + dbg_printf (_("error: out-of-range year %"PRIdMAX"\n"), year); + return false; + } + + return true; +} + +static table const * _GL_ATTRIBUTE_PURE +lookup_zone (parser_control const *pc, char const *name) +{ + table const *tp; + + for (tp = universal_time_zone_table; tp->name; tp++) + if (strcmp (name, tp->name) == 0) + return tp; + + /* Try local zone abbreviations before those in time_zone_table, as + the local ones are more likely to be right. */ + for (tp = pc->local_time_zone_table; tp->name; tp++) + if (strcmp (name, tp->name) == 0) + return tp; + + for (tp = time_zone_table; tp->name; tp++) + if (strcmp (name, tp->name) == 0) + return tp; + + return NULL; +} + +#if ! HAVE_TM_GMTOFF +/* Yield the difference between *A and *B, + measured in seconds, ignoring leap seconds. + The body of this function is taken directly from the GNU C Library; + see strftime.c. */ +static int +tm_diff (const struct tm *a, const struct tm *b) +{ + /* Compute intervening leap days correctly even if year is negative. + Take care to avoid int overflow in leap day calculations, + but it's OK to assume that A and B are close to each other. */ + int a4 = SHR (a->tm_year, 2) + SHR (TM_YEAR_BASE, 2) - ! (a->tm_year & 3); + int b4 = SHR (b->tm_year, 2) + SHR (TM_YEAR_BASE, 2) - ! (b->tm_year & 3); + int a100 = a4 / 25 - (a4 % 25 < 0); + int b100 = b4 / 25 - (b4 % 25 < 0); + int a400 = SHR (a100, 2); + int b400 = SHR (b100, 2); + int intervening_leap_days = (a4 - b4) - (a100 - b100) + (a400 - b400); + int years = a->tm_year - b->tm_year; + int days = (365 * years + intervening_leap_days + + (a->tm_yday - b->tm_yday)); + return (60 * (60 * (24 * days + (a->tm_hour - b->tm_hour)) + + (a->tm_min - b->tm_min)) + + (a->tm_sec - b->tm_sec)); +} +#endif /* ! HAVE_TM_GMTOFF */ + +static table const * +lookup_word (parser_control const *pc, char *word) +{ + char *p; + char *q; + idx_t wordlen; + table const *tp; + bool period_found; + bool abbrev; + + /* Make it uppercase. */ + for (p = word; *p; p++) + *p = c_toupper (to_uchar (*p)); + + for (tp = meridian_table; tp->name; tp++) + if (strcmp (word, tp->name) == 0) + return tp; + + /* See if we have an abbreviation for a month. */ + wordlen = strlen (word); + abbrev = wordlen == 3 || (wordlen == 4 && word[3] == '.'); + + for (tp = month_and_day_table; tp->name; tp++) + if ((abbrev ? strncmp (word, tp->name, 3) : strcmp (word, tp->name)) == 0) + return tp; + + if ((tp = lookup_zone (pc, word))) + return tp; + + if (strcmp (word, dst_table[0].name) == 0) + return dst_table; + + for (tp = time_units_table; tp->name; tp++) + if (strcmp (word, tp->name) == 0) + return tp; + + /* Strip off any plural and try the units table again. */ + if (word[wordlen - 1] == 'S') + { + word[wordlen - 1] = '\0'; + for (tp = time_units_table; tp->name; tp++) + if (strcmp (word, tp->name) == 0) + return tp; + word[wordlen - 1] = 'S'; /* For "this" in relative_time_table. */ + } + + for (tp = relative_time_table; tp->name; tp++) + if (strcmp (word, tp->name) == 0) + return tp; + + /* Military time zones. */ + if (wordlen == 1) + for (tp = military_table; tp->name; tp++) + if (word[0] == tp->name[0]) + return tp; + + /* Drop out any periods and try the time zone table again. */ + for (period_found = false, p = q = word; (*p = *q); q++) + if (*q == '.') + period_found = true; + else + p++; + if (period_found && (tp = lookup_zone (pc, word))) + return tp; + + return NULL; +} + +static int +yylex (union YYSTYPE *lvalp, parser_control *pc) +{ + unsigned char c; + + for (;;) + { + while (c = *pc->input, c_isspace (c)) + pc->input++; + + if (c_isdigit (c) || c == '-' || c == '+') + { + char const *p = pc->input; + int sign; + if (c == '-' || c == '+') + { + sign = c == '-' ? -1 : 1; + while (c = *(pc->input = ++p), c_isspace (c)) + continue; + if (! c_isdigit (c)) + /* skip the '-' sign */ + continue; + } + else + sign = 0; + + time_t value = 0; + do + { + if (INT_MULTIPLY_WRAPV (value, 10, &value)) + return '?'; + if (INT_ADD_WRAPV (value, sign < 0 ? '0' - c : c - '0', &value)) + return '?'; + c = *++p; + } + while (c_isdigit (c)); + + if ((c == '.' || c == ',') && c_isdigit (p[1])) + { + time_t s = value; + int digits; + + /* Accumulate fraction, to ns precision. */ + p++; + int ns = *p++ - '0'; + for (digits = 2; digits <= LOG10_BILLION; digits++) + { + ns *= 10; + if (c_isdigit (*p)) + ns += *p++ - '0'; + } + + /* Skip excess digits, truncating toward -Infinity. */ + if (sign < 0) + for (; c_isdigit (*p); p++) + if (*p != '0') + { + ns++; + break; + } + while (c_isdigit (*p)) + p++; + + /* Adjust to the timespec convention, which is that + tv_nsec is always a positive offset even if tv_sec is + negative. */ + if (sign < 0 && ns) + { + if (INT_SUBTRACT_WRAPV (s, 1, &s)) + return '?'; + ns = BILLION - ns; + } + + lvalp->timespec.tv_sec = s; + lvalp->timespec.tv_nsec = ns; + pc->input = p; + return sign ? tSDECIMAL_NUMBER : tUDECIMAL_NUMBER; + } + else + { + lvalp->textintval.negative = sign < 0; + lvalp->textintval.value = value; + lvalp->textintval.digits = p - pc->input; + pc->input = p; + return sign ? tSNUMBER : tUNUMBER; + } + } + + if (c_isalpha (c)) + { + char buff[20]; + char *p = buff; + table const *tp; + + do + { + if (p < buff + sizeof buff - 1) + *p++ = c; + c = *++pc->input; + } + while (c_isalpha (c) || c == '.'); + + *p = '\0'; + tp = lookup_word (pc, buff); + if (! tp) + { + if (debugging (pc)) + dbg_printf (_("error: unknown word '%s'\n"), buff); + return '?'; + } + lvalp->intval = tp->value; + return tp->type; + } + + if (c != '(') + return to_uchar (*pc->input++); + + idx_t count = 0; + do + { + c = *pc->input++; + if (c == '\0') + return c; + if (c == '(') + count++; + else if (c == ')') + count--; + } + while (count != 0); + } +} + +/* Do nothing if the parser reports an error. */ +static int +yyerror (_GL_UNUSED parser_control const *pc, + _GL_UNUSED char const *s) +{ + return 0; +} + +/* If *TM0 is the old and *TM1 is the new value of a struct tm after + passing it to mktime_z, return true if it's OK. It's not OK if + mktime failed or if *TM0 has out-of-range mainline members. + The caller should set TM1->tm_wday to -1 before calling mktime, + as a negative tm_wday is how mktime failure is inferred. */ + +static bool +mktime_ok (struct tm const *tm0, struct tm const *tm1) +{ + if (tm1->tm_wday < 0) + return false; + + return ! ((tm0->tm_sec ^ tm1->tm_sec) + | (tm0->tm_min ^ tm1->tm_min) + | (tm0->tm_hour ^ tm1->tm_hour) + | (tm0->tm_mday ^ tm1->tm_mday) + | (tm0->tm_mon ^ tm1->tm_mon) + | (tm0->tm_year ^ tm1->tm_year)); +} + +/* Debugging: format a 'struct tm' into a buffer, taking the parser's + timezone information into account (if pc != NULL). */ +static char const * +debug_strfdatetime (struct tm const *tm, parser_control const *pc, + char *buf, int n) +{ + /* TODO: + 1. find an optimal way to print date string in a clear and unambiguous + format. Currently, always add '(Y-M-D)' prefix. + Consider '2016y01m10d' or 'year(2016) month(01) day(10)'. + + If the user needs debug printing, it means he/she already having + issues with the parsing - better to avoid formats that could + be mis-interpreted (e.g., just YYYY-MM-DD). + + 2. Can strftime be used instead? + depends if it is portable and can print invalid dates on all systems. + + 3. Print timezone information ? + + 4. Print DST information ? + + 5. Print nanosecond information ? + + NOTE: + Printed date/time values might not be valid, e.g., '2016-02-31' + or '2016-19-2016' . These are the values as parsed from the user + string, before validation. + */ + int m = nstrftime (buf, n, "(Y-M-D) %Y-%m-%d %H:%M:%S", tm, 0, 0); + + /* If parser_control information was provided (for timezone), + and there's enough space in the buffer, add timezone info. */ + if (pc && m < n && pc->zones_seen) + { + int tz = pc->time_zone; + + /* Account for DST if tLOCAL_ZONE was seen. */ + if (pc->local_zones_seen && !pc->zones_seen && 0 < pc->local_isdst) + tz += 60 * 60; + + char time_zone_buf[TIME_ZONE_BUFSIZE]; + snprintf (&buf[m], n - m, " TZ=%s", time_zone_str (tz, time_zone_buf)); + } + return buf; +} + +static char const * +debug_strfdate (struct tm const *tm, char *buf, int n) +{ + char tm_year_buf[TM_YEAR_BUFSIZE]; + snprintf (buf, n, "(Y-M-D) %s-%02d-%02d", + tm_year_str (tm->tm_year, tm_year_buf), + tm->tm_mon + 1, tm->tm_mday); + return buf; +} + +static char const * +debug_strftime (struct tm const *tm, char *buf, int n) +{ + snprintf (buf, n, "%02d:%02d:%02d", tm->tm_hour, tm->tm_min, tm->tm_sec); + return buf; +} + +/* If mktime_ok failed, display the failed time values, + and provide possible hints. Example output: + + date: error: invalid date/time value: + date: user provided time: '(Y-M-D) 2006-04-02 02:45:00' + date: normalized time: '(Y-M-D) 2006-04-02 03:45:00' + date: __ + date: possible reasons: + date: non-existing due to daylight-saving time; + date: numeric values overflow; + date: missing timezone; + */ +static void +debug_mktime_not_ok (struct tm const *tm0, struct tm const *tm1, + parser_control const *pc, bool time_zone_seen) +{ + /* TODO: handle t == -1 (as in 'mktime_ok'). */ + char tmp[DBGBUFSIZE]; + int i; + const bool eq_sec = (tm0->tm_sec == tm1->tm_sec); + const bool eq_min = (tm0->tm_min == tm1->tm_min); + const bool eq_hour = (tm0->tm_hour == tm1->tm_hour); + const bool eq_mday = (tm0->tm_mday == tm1->tm_mday); + const bool eq_month = (tm0->tm_mon == tm1->tm_mon); + const bool eq_year = (tm0->tm_year == tm1->tm_year); + + const bool dst_shift = eq_sec && eq_min && !eq_hour + && eq_mday && eq_month && eq_year; + + if (!debugging (pc)) + return; + + dbg_printf (_("error: invalid date/time value:\n")); + dbg_printf (_(" user provided time: '%s'\n"), + debug_strfdatetime (tm0, pc, tmp, sizeof tmp)); + dbg_printf (_(" normalized time: '%s'\n"), + debug_strfdatetime (tm1, pc, tmp, sizeof tmp)); + /* The format must be aligned with debug_strfdatetime and the two + DEBUG statements above. This string is not translated. */ + i = snprintf (tmp, sizeof tmp, + " %4s %2s %2s %2s %2s %2s", + eq_year ? "" : "----", + eq_month ? "" : "--", + eq_mday ? "" : "--", + eq_hour ? "" : "--", + eq_min ? "" : "--", + eq_sec ? "" : "--"); + /* Trim trailing whitespace. */ + if (0 <= i) + { + if (sizeof tmp - 1 < i) + i = sizeof tmp - 1; + while (0 < i && tmp[i - 1] == ' ') + --i; + tmp[i] = '\0'; + } + dbg_printf ("%s\n", tmp); + + dbg_printf (_(" possible reasons:\n")); + if (dst_shift) + dbg_printf (_(" non-existing due to daylight-saving time;\n")); + if (!eq_mday && !eq_month) + dbg_printf (_(" invalid day/month combination;\n")); + dbg_printf (_(" numeric values overflow;\n")); + dbg_printf (" %s\n", (time_zone_seen ? _("incorrect timezone") + : _("missing timezone"))); +} + +/* Parse a date/time string, storing the resulting time value into *RESULT. + The string itself is pointed to by P. Return true if successful. + P can be an incomplete or relative time specification; if so, use + *NOW as the basis for the returned time. Default to timezone + TZDEFAULT, which corresponds to tzalloc (TZSTRING). */ +static bool +parse_datetime_body (struct timespec *result, char const *p, + struct timespec const *now, unsigned int flags, + timezone_t tzdefault, char const *tzstring) +{ + struct tm tm; + struct tm tm0; + char time_zone_buf[TIME_ZONE_BUFSIZE]; + char dbg_tm[DBGBUFSIZE]; + bool ok = false; + char const *input_sentinel = p + strlen (p); + char *tz1alloc = NULL; + + /* A reasonable upper bound for the size of ordinary TZ strings. + Use heap allocation if TZ's length exceeds this. */ + enum { TZBUFSIZE = 100 }; + char tz1buf[TZBUFSIZE]; + + struct timespec gettime_buffer; + if (! now) + { + gettime (&gettime_buffer); + now = &gettime_buffer; + } + + time_t Start = now->tv_sec; + int Start_ns = now->tv_nsec; + + unsigned char c; + while (c = *p, c_isspace (c)) + p++; + + timezone_t tz = tzdefault; + + /* Store a local copy prior to first "goto". Without this, a prior use + below of RELATIVE_TIME_0 on the RHS might translate to an assignment- + to-temporary, which would trigger a -Wjump-misses-init warning. */ + const relative_time rel_time_0 = RELATIVE_TIME_0; + + if (strncmp (p, "TZ=\"", 4) == 0) + { + char const *tzbase = p + 4; + idx_t tzsize = 1; + char const *s; + + for (s = tzbase; *s; s++, tzsize++) + if (*s == '\\') + { + s++; + if (! (*s == '\\' || *s == '"')) + break; + } + else if (*s == '"') + { + timezone_t tz1; + char *tz1string = tz1buf; + char *z; + if (TZBUFSIZE < tzsize) + { + tz1alloc = malloc (tzsize); + if (!tz1alloc) + goto fail; + tz1string = tz1alloc; + } + z = tz1string; + for (s = tzbase; *s != '"'; s++) + *z++ = *(s += *s == '\\'); + *z = '\0'; + tz1 = tzalloc (tz1string); + if (!tz1) + goto fail; + tz = tz1; + tzstring = tz1string; + + p = s + 1; + while (c = *p, c_isspace (c)) + p++; + + break; + } + } + + struct tm tmp; + if (! localtime_rz (tz, &now->tv_sec, &tmp)) + goto fail; + + /* As documented, be careful to treat the empty string just like + a date string of "0". Without this, an empty string would be + declared invalid when parsed during a DST transition. */ + if (*p == '\0') + p = "0"; + + parser_control pc; + pc.input = p; +#ifdef GNULIB_PARSE_DATETIME2 + pc.parse_datetime_debug = (flags & PARSE_DATETIME_DEBUG) != 0; +#endif + if (INT_ADD_WRAPV (tmp.tm_year, TM_YEAR_BASE, &pc.year.value)) + { + if (debugging (&pc)) + dbg_printf (_("error: initial year out of range\n")); + goto fail; + } + pc.year.digits = 0; + pc.month = tmp.tm_mon + 1; + pc.day = tmp.tm_mday; + pc.hour = tmp.tm_hour; + pc.minutes = tmp.tm_min; + pc.seconds.tv_sec = tmp.tm_sec; + pc.seconds.tv_nsec = Start_ns; + tm.tm_isdst = tmp.tm_isdst; + + pc.meridian = MER24; + pc.rel = rel_time_0; + pc.timespec_seen = false; + pc.rels_seen = false; + pc.dates_seen = 0; + pc.days_seen = 0; + pc.times_seen = 0; + pc.local_zones_seen = 0; + pc.dsts_seen = 0; + pc.zones_seen = 0; + pc.year_seen = false; + pc.debug_dates_seen = false; + pc.debug_days_seen = false; + pc.debug_times_seen = false; + pc.debug_local_zones_seen = false; + pc.debug_zones_seen = false; + pc.debug_year_seen = false; + pc.debug_ordinal_day_seen = false; + +#if HAVE_STRUCT_TM_TM_ZONE + pc.local_time_zone_table[0].name = tmp.tm_zone; + pc.local_time_zone_table[0].type = tLOCAL_ZONE; + pc.local_time_zone_table[0].value = tmp.tm_isdst; + pc.local_time_zone_table[1].name = NULL; + + /* Probe the names used in the next three calendar quarters, looking + for a tm_isdst different from the one we already have. */ + { + int quarter; + for (quarter = 1; quarter <= 3; quarter++) + { + time_t probe; + if (INT_ADD_WRAPV (Start, quarter * (90 * 24 * 60 * 60), &probe)) + break; + struct tm probe_tm; + if (localtime_rz (tz, &probe, &probe_tm) && probe_tm.tm_zone + && probe_tm.tm_isdst != pc.local_time_zone_table[0].value) + { + { + pc.local_time_zone_table[1].name = probe_tm.tm_zone; + pc.local_time_zone_table[1].type = tLOCAL_ZONE; + pc.local_time_zone_table[1].value = probe_tm.tm_isdst; + pc.local_time_zone_table[2].name = NULL; + } + break; + } + } + } +#else +#if HAVE_TZNAME + { +# if !HAVE_DECL_TZNAME + extern char *tzname[]; +# endif + int i; + for (i = 0; i < 2; i++) + { + pc.local_time_zone_table[i].name = tzname[i]; + pc.local_time_zone_table[i].type = tLOCAL_ZONE; + pc.local_time_zone_table[i].value = i; + } + pc.local_time_zone_table[i].name = NULL; + } +#else + pc.local_time_zone_table[0].name = NULL; +#endif +#endif + + if (pc.local_time_zone_table[0].name && pc.local_time_zone_table[1].name + && ! strcmp (pc.local_time_zone_table[0].name, + pc.local_time_zone_table[1].name)) + { + /* This locale uses the same abbreviation for standard and + daylight times. So if we see that abbreviation, we don't + know whether it's daylight time. */ + pc.local_time_zone_table[0].value = -1; + pc.local_time_zone_table[1].name = NULL; + } + + if (yyparse (&pc) != 0) + { + if (debugging (&pc)) + dbg_printf ((input_sentinel <= pc.input + ? _("error: parsing failed\n") + : _("error: parsing failed, stopped at '%s'\n")), + pc.input); + goto fail; + } + + + /* Determine effective timezone source. */ + + if (debugging (&pc)) + { + dbg_printf (_("input timezone: ")); + + if (pc.timespec_seen) + fprintf (stderr, _("'@timespec' - always UTC")); + else if (pc.zones_seen) + fprintf (stderr, _("parsed date/time string")); + else if (tzstring) + { + if (tz != tzdefault) + fprintf (stderr, _("TZ=\"%s\" in date string"), tzstring); + else if (STREQ (tzstring, "UTC0")) + { + /* Special case: 'date -u' sets TZ="UTC0". */ + fprintf (stderr, _("TZ=\"UTC0\" environment value or -u")); + } + else + fprintf (stderr, _("TZ=\"%s\" environment value"), tzstring); + } + else + fprintf (stderr, _("system default")); + + /* Account for DST changes if tLOCAL_ZONE was seen. + local timezone only changes DST and is relative to the + default timezone.*/ + if (pc.local_zones_seen && !pc.zones_seen && 0 < pc.local_isdst) + fprintf (stderr, ", dst"); + + if (pc.zones_seen) + fprintf (stderr, " (%s)", time_zone_str (pc.time_zone, time_zone_buf)); + + fputc ('\n', stderr); + } + + if (pc.timespec_seen) + *result = pc.seconds; + else + { + if (1 < (pc.times_seen | pc.dates_seen | pc.days_seen | pc.dsts_seen + | (pc.local_zones_seen + pc.zones_seen))) + { + if (debugging (&pc)) + { + if (pc.times_seen > 1) + dbg_printf ("error: seen multiple time parts\n"); + if (pc.dates_seen > 1) + dbg_printf ("error: seen multiple date parts\n"); + if (pc.days_seen > 1) + dbg_printf ("error: seen multiple days parts\n"); + if (pc.dsts_seen > 1) + dbg_printf ("error: seen multiple daylight-saving parts\n"); + if ((pc.local_zones_seen + pc.zones_seen) > 1) + dbg_printf ("error: seen multiple time-zone parts\n"); + } + goto fail; + } + + if (! to_tm_year (pc.year, debugging (&pc), &tm.tm_year) + || INT_ADD_WRAPV (pc.month, -1, &tm.tm_mon) + || INT_ADD_WRAPV (pc.day, 0, &tm.tm_mday)) + { + if (debugging (&pc)) + dbg_printf (_("error: year, month, or day overflow\n")); + goto fail; + } + if (pc.times_seen || (pc.rels_seen && ! pc.dates_seen && ! pc.days_seen)) + { + tm.tm_hour = to_hour (pc.hour, pc.meridian); + if (tm.tm_hour < 0) + { + char const *mrd = (pc.meridian == MERam ? "am" + : pc.meridian == MERpm ?"pm" : ""); + if (debugging (&pc)) + dbg_printf (_("error: invalid hour %"PRIdMAX"%s\n"), + pc.hour, mrd); + goto fail; + } + tm.tm_min = pc.minutes; + tm.tm_sec = pc.seconds.tv_sec; + if (debugging (&pc)) + dbg_printf ((pc.times_seen + ? _("using specified time as starting value: '%s'\n") + : _("using current time as starting value: '%s'\n")), + debug_strftime (&tm, dbg_tm, sizeof dbg_tm)); + } + else + { + tm.tm_hour = tm.tm_min = tm.tm_sec = 0; + pc.seconds.tv_nsec = 0; + if (debugging (&pc)) + dbg_printf ("warning: using midnight as starting time: 00:00:00\n"); + } + + /* Let mktime deduce tm_isdst if we have an absolute timestamp. */ + if (pc.dates_seen | pc.days_seen | pc.times_seen) + tm.tm_isdst = -1; + + /* But if the input explicitly specifies local time with or without + DST, give mktime that information. */ + if (pc.local_zones_seen) + tm.tm_isdst = pc.local_isdst; + + tm0.tm_sec = tm.tm_sec; + tm0.tm_min = tm.tm_min; + tm0.tm_hour = tm.tm_hour; + tm0.tm_mday = tm.tm_mday; + tm0.tm_mon = tm.tm_mon; + tm0.tm_year = tm.tm_year; + tm0.tm_isdst = tm.tm_isdst; + tm.tm_wday = -1; + + Start = mktime_z (tz, &tm); + + if (! mktime_ok (&tm0, &tm)) + { + bool repaired = false; + bool time_zone_seen = pc.zones_seen != 0; + if (time_zone_seen) + { + /* Guard against falsely reporting errors near the time_t + boundaries when parsing times in other time zones. For + example, suppose the input string "1969-12-31 23:00:00 -0100", + the current time zone is 8 hours ahead of UTC, and the min + time_t value is 1970-01-01 00:00:00 UTC. Then the min + localtime value is 1970-01-01 08:00:00, and mktime will + therefore fail on 1969-12-31 23:00:00. To work around the + problem, set the time zone to 1 hour behind UTC temporarily + by setting TZ="XXX1:00" and try mktime again. */ + + char tz2buf[sizeof "XXX" - 1 + TIME_ZONE_BUFSIZE]; + tz2buf[0] = tz2buf[1] = tz2buf[2] = 'X'; + time_zone_str (pc.time_zone, &tz2buf[3]); + timezone_t tz2 = tzalloc (tz2buf); + if (!tz2) + { + if (debugging (&pc)) + dbg_printf (_("error: tzalloc (\"%s\") failed\n"), tz2buf); + goto fail; + } + tm.tm_sec = tm0.tm_sec; + tm.tm_min = tm0.tm_min; + tm.tm_hour = tm0.tm_hour; + tm.tm_mday = tm0.tm_mday; + tm.tm_mon = tm0.tm_mon; + tm.tm_year = tm0.tm_year; + tm.tm_isdst = tm0.tm_isdst; + tm.tm_wday = -1; + Start = mktime_z (tz2, &tm); + repaired = mktime_ok (&tm0, &tm); + tzfree (tz2); + } + + if (! repaired) + { + debug_mktime_not_ok (&tm0, &tm, &pc, time_zone_seen); + goto fail; + } + } + + char dbg_ord[DBGBUFSIZE]; + + if (pc.days_seen && ! pc.dates_seen) + { + intmax_t dayincr; + tm.tm_yday = -1; + if (! (INT_MULTIPLY_WRAPV ((pc.day_ordinal + - (0 < pc.day_ordinal + && tm.tm_wday != pc.day_number)), + 7, &dayincr) + || INT_ADD_WRAPV ((pc.day_number - tm.tm_wday + 7) % 7, + dayincr, &dayincr) + || INT_ADD_WRAPV (dayincr, tm.tm_mday, &tm.tm_mday))) + { + tm.tm_isdst = -1; + Start = mktime_z (tz, &tm); + } + + if (tm.tm_yday < 0) + { + if (debugging (&pc)) + dbg_printf (_("error: day '%s' " + "(day ordinal=%"PRIdMAX" number=%d) " + "resulted in an invalid date: '%s'\n"), + str_days (&pc, dbg_ord, sizeof dbg_ord), + pc.day_ordinal, pc.day_number, + debug_strfdatetime (&tm, &pc, dbg_tm, + sizeof dbg_tm)); + goto fail; + } + + if (debugging (&pc)) + dbg_printf (_("new start date: '%s' is '%s'\n"), + str_days (&pc, dbg_ord, sizeof dbg_ord), + debug_strfdatetime (&tm, &pc, dbg_tm, sizeof dbg_tm)); + + } + + if (debugging (&pc)) + { + if (!pc.dates_seen && !pc.days_seen) + dbg_printf (_("using current date as starting value: '%s'\n"), + debug_strfdate (&tm, dbg_tm, sizeof dbg_tm)); + + if (pc.days_seen && pc.dates_seen) + dbg_printf (_("warning: day (%s) ignored when explicit dates " + "are given\n"), + str_days (&pc, dbg_ord, sizeof dbg_ord)); + + dbg_printf (_("starting date/time: '%s'\n"), + debug_strfdatetime (&tm, &pc, dbg_tm, sizeof dbg_tm)); + } + + /* Add relative date. */ + if (pc.rel.year | pc.rel.month | pc.rel.day) + { + if (debugging (&pc)) + { + if ((pc.rel.year != 0 || pc.rel.month != 0) && tm.tm_mday != 15) + dbg_printf (_("warning: when adding relative months/years, " + "it is recommended to specify the 15th of the " + "months\n")); + + if (pc.rel.day != 0 && tm.tm_hour != 12) + dbg_printf (_("warning: when adding relative days, " + "it is recommended to specify noon\n")); + } + + int year, month, day; + if (INT_ADD_WRAPV (tm.tm_year, pc.rel.year, &year) + || INT_ADD_WRAPV (tm.tm_mon, pc.rel.month, &month) + || INT_ADD_WRAPV (tm.tm_mday, pc.rel.day, &day)) + { + if (debugging (&pc)) + dbg_printf (_("error: %s:%d\n"), __FILE__, __LINE__); + goto fail; + } + tm.tm_year = year; + tm.tm_mon = month; + tm.tm_mday = day; + tm.tm_hour = tm0.tm_hour; + tm.tm_min = tm0.tm_min; + tm.tm_sec = tm0.tm_sec; + tm.tm_isdst = tm0.tm_isdst; + tm.tm_wday = -1; + Start = mktime_z (tz, &tm); + if (tm.tm_wday < 0) + { + if (debugging (&pc)) + dbg_printf (_("error: adding relative date resulted " + "in an invalid date: '%s'\n"), + debug_strfdatetime (&tm, &pc, dbg_tm, + sizeof dbg_tm)); + goto fail; + } + + if (debugging (&pc)) + { + dbg_printf (_("after date adjustment " + "(%+"PRIdMAX" years, %+"PRIdMAX" months, " + "%+"PRIdMAX" days),\n"), + pc.rel.year, pc.rel.month, pc.rel.day); + dbg_printf (_(" new date/time = '%s'\n"), + debug_strfdatetime (&tm, &pc, dbg_tm, + sizeof dbg_tm)); + + /* Warn about crossing DST due to time adjustment. + Example: https://bugs.gnu.org/8357 + env TZ=Europe/Helsinki \ + date --debug \ + -d 'Mon Mar 28 00:36:07 2011 EEST 1 day ago' + + This case is different than DST changes due to time adjustment, + i.e., "1 day ago" vs "24 hours ago" are calculated in different + places. + + 'tm0.tm_isdst' contains the DST of the input date, + 'tm.tm_isdst' is the normalized result after calling + mktime (&tm). + */ + if (tm0.tm_isdst != -1 && tm.tm_isdst != tm0.tm_isdst) + dbg_printf (_("warning: daylight saving time changed after " + "date adjustment\n")); + + /* Warn if the user did not ask to adjust days but mday changed, + or + user did not ask to adjust months/days but the month changed. + + Example for first case: + 2016-05-31 + 1 month => 2016-06-31 => 2016-07-01. + User asked to adjust month, but the day changed from 31 to 01. + + Example for second case: + 2016-02-29 + 1 year => 2017-02-29 => 2017-03-01. + User asked to adjust year, but the month changed from 02 to 03. + */ + if (pc.rel.day == 0 + && (tm.tm_mday != day + || (pc.rel.month == 0 && tm.tm_mon != month))) + { + dbg_printf (_("warning: month/year adjustment resulted in " + "shifted dates:\n")); + char tm_year_buf[TM_YEAR_BUFSIZE]; + dbg_printf (_(" adjusted Y M D: %s %02d %02d\n"), + tm_year_str (year, tm_year_buf), month + 1, day); + dbg_printf (_(" normalized Y M D: %s %02d %02d\n"), + tm_year_str (tm.tm_year, tm_year_buf), + tm.tm_mon + 1, tm.tm_mday); + } + } + + } + + /* The only "output" of this if-block is an updated Start value, + so this block must follow others that clobber Start. */ + if (pc.zones_seen) + { + bool overflow = false; +#ifdef HAVE_TM_GMTOFF + long int utcoff = tm.tm_gmtoff; +#else + time_t t = Start; + struct tm gmt; + int utcoff = (gmtime_r (&t, &gmt) + ? tm_diff (&tm, &gmt) + : (overflow = true, 0)); +#endif + intmax_t delta; + overflow |= INT_SUBTRACT_WRAPV (pc.time_zone, utcoff, &delta); + time_t t1; + overflow |= INT_SUBTRACT_WRAPV (Start, delta, &t1); + if (overflow) + { + if (debugging (&pc)) + dbg_printf (_("error: timezone %d caused time_t overflow\n"), + pc.time_zone); + goto fail; + } + Start = t1; + } + + if (debugging (&pc)) + { + intmax_t Starti = Start; + dbg_printf (_("'%s' = %"PRIdMAX" epoch-seconds\n"), + debug_strfdatetime (&tm, &pc, dbg_tm, sizeof dbg_tm), + Starti); + } + + + /* Add relative hours, minutes, and seconds. On hosts that support + leap seconds, ignore the possibility of leap seconds; e.g., + "+ 10 minutes" adds 600 seconds, even if one of them is a + leap second. Typically this is not what the user wants, but it's + too hard to do it the other way, because the time zone indicator + must be applied before relative times, and if mktime is applied + again the time zone will be lost. */ + { + intmax_t orig_ns = pc.seconds.tv_nsec; + intmax_t sum_ns = orig_ns + pc.rel.ns; + int normalized_ns = (sum_ns % BILLION + BILLION) % BILLION; + int d4 = (sum_ns - normalized_ns) / BILLION; + intmax_t d1, t1, d2, t2, t3; + time_t t4; + if (INT_MULTIPLY_WRAPV (pc.rel.hour, 60 * 60, &d1) + || INT_ADD_WRAPV (Start, d1, &t1) + || INT_MULTIPLY_WRAPV (pc.rel.minutes, 60, &d2) + || INT_ADD_WRAPV (t1, d2, &t2) + || INT_ADD_WRAPV (t2, pc.rel.seconds, &t3) + || INT_ADD_WRAPV (t3, d4, &t4)) + { + if (debugging (&pc)) + dbg_printf (_("error: adding relative time caused an " + "overflow\n")); + goto fail; + } + + result->tv_sec = t4; + result->tv_nsec = normalized_ns; + + if (debugging (&pc) + && (pc.rel.hour | pc.rel.minutes | pc.rel.seconds | pc.rel.ns)) + { + dbg_printf (_("after time adjustment (%+"PRIdMAX" hours, " + "%+"PRIdMAX" minutes, " + "%+"PRIdMAX" seconds, %+d ns),\n"), + pc.rel.hour, pc.rel.minutes, pc.rel.seconds, + pc.rel.ns); + intmax_t t4i = t4; + dbg_printf (_(" new time = %"PRIdMAX" epoch-seconds\n"), t4i); + + /* Warn about crossing DST due to time adjustment. + Example: https://bugs.gnu.org/8357 + env TZ=Europe/Helsinki \ + date --debug \ + -d 'Mon Mar 28 00:36:07 2011 EEST 24 hours ago' + + This case is different than DST changes due to days adjustment, + i.e., "1 day ago" vs "24 hours ago" are calculated in different + places. + + 'tm.tm_isdst' contains the date after date adjustment. */ + struct tm lmt; + if (tm.tm_isdst != -1 && localtime_rz (tz, &result->tv_sec, &lmt) + && tm.tm_isdst != lmt.tm_isdst) + dbg_printf (_("warning: daylight saving time changed after " + "time adjustment\n")); + } + } + } + + if (debugging (&pc)) + { + /* Special case: using 'date -u' simply set TZ=UTC0 */ + if (! tzstring) + dbg_printf (_("timezone: system default\n")); + else if (STREQ (tzstring, "UTC0")) + dbg_printf (_("timezone: Universal Time\n")); + else + dbg_printf (_("timezone: TZ=\"%s\" environment value\n"), tzstring); + + intmax_t sec = result->tv_sec; + int nsec = result->tv_nsec; + dbg_printf (_("final: %"PRIdMAX".%09d (epoch-seconds)\n"), + sec, nsec); + + struct tm gmt, lmt; + bool got_utc = !!gmtime_r (&result->tv_sec, &gmt); + if (got_utc) + dbg_printf (_("final: %s (UTC)\n"), + debug_strfdatetime (&gmt, NULL, + dbg_tm, sizeof dbg_tm)); + if (localtime_rz (tz, &result->tv_sec, &lmt)) + { +#ifdef HAVE_TM_GMTOFF + bool got_utcoff = true; + long int utcoff = lmt.tm_gmtoff; +#else + bool got_utcoff = got_utc; + int utcoff; + if (got_utcoff) + utcoff = tm_diff (&lmt, &gmt); +#endif + if (got_utcoff) + dbg_printf (_("final: %s (UTC%s)\n"), + debug_strfdatetime (&lmt, NULL, dbg_tm, sizeof dbg_tm), + time_zone_str (utcoff, time_zone_buf)); + else + dbg_printf (_("final: %s (unknown time zone offset)\n"), + debug_strfdatetime (&lmt, NULL, dbg_tm, sizeof dbg_tm)); + } + } + + ok = true; + + fail: + if (tz != tzdefault) + tzfree (tz); + free (tz1alloc); + return ok; +} + +#ifdef GNULIB_PARSE_DATETIME2 +/* Parse a date/time string, storing the resulting time value into *RESULT. + The string itself is pointed to by P. Return true if successful. + P can be an incomplete or relative time specification; if so, use + *NOW as the basis for the returned time. Default to timezone + TZDEFAULT, which corresponds to tzalloc (TZSTRING). */ +bool +parse_datetime2 (struct timespec *result, char const *p, + struct timespec const *now, unsigned int flags, + timezone_t tzdefault, char const *tzstring) +{ + return parse_datetime_body (result, p, now, flags, tzdefault, tzstring); +} +#endif + + +/* The plain interface: run with debug=false and the default timezone. */ +bool +parse_datetime (struct timespec *result, char const *p, + struct timespec const *now) +{ + char const *tzstring = getenv ("TZ"); + timezone_t tz = tzalloc (tzstring); + if (!tz) + return false; + bool ok = parse_datetime_body (result, p, now, 0, tz, tzstring); + tzfree (tz); + return ok; +} + +#if TEST + +int +main (int ac, char **av) +{ + char buff[BUFSIZ]; + + printf ("Enter date, or blank line to exit.\n\t> "); + fflush (stdout); + + buff[BUFSIZ - 1] = '\0'; + while (fgets (buff, BUFSIZ - 1, stdin) && buff[0]) + { + struct timespec d; + struct tm const *tm; + if (! parse_datetime (&d, buff, NULL)) + printf ("Bad format - couldn't convert.\n"); + else if (! (tm = localtime (&d.tv_sec))) + { + intmax_t sec = d.tv_sec; + printf ("localtime (%"PRIdMAX") failed\n", sec); + } + else + { + int ns = d.tv_nsec; + char tm_year_buf[TM_YEAR_BUFSIZE]; + printf ("%s-%02d-%02d %02d:%02d:%02d.%09d\n", + tm_year_str (tm->tm_year, tm_year_buf), + tm->tm_mon + 1, tm->tm_mday, + tm->tm_hour, tm->tm_min, tm->tm_sec, ns); + } + printf ("\t> "); + fflush (stdout); + } + return 0; +} +#endif /* TEST */ |