getdate.y

gnu tar 源码包。 tar 软件是 Unix 系统下的一个打包软件

      { $$ = RELATIVE_TIME_0; $$.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
      { $$ = RELATIVE_TIME_0; $$.day = $1 * $2; }
  | tUNUMBER tDAY_UNIT
      { $$ = RELATIVE_TIME_0; $$.day = $1.value * $2; }
  | 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
      { $$ = RELATIVE_TIME_0; $$.day = $1.value * $2; }
  | 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; }
  ;

seconds: signed_seconds | unsigned_seconds;

signed_seconds:
    tSDECIMAL_NUMBER
  | tSNUMBER
      { $$.tv_sec = $1.value; $$.tv_nsec = 0; }
  ;

unsigned_seconds:
    tUDECIMAL_NUMBER
  | tUNUMBER
      { $$.tv_sec = $1.value; $$.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);
	pc->rel.ns += $2.ns;
	pc->rel.seconds += $2.seconds;
	pc->rel.minutes += $2.minutes;
	pc->rel.hour += $2.hour;
	pc->rel.day += $2.day;
	pc->rel.month += $2.month;
	pc->rel.year += $2.year;
	pc->rels_seen = true;
      }
  ;

o_colon_minutes:
    /* empty */
      { $$ = -1; }
  | ':' tUNUMBER
      { $$ = $2.value; }
  ;

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

%%

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_UNIT,	 1 },
  { "YESTERDAY",tDAY_UNIT,	-1 },
  { "TODAY",	tDAY_UNIT,	 0 },
  { "NOW",	tDAY_UNIT,	 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 },
  { NULL, 0, 0 }
};

/* The universal time zone table.  These labels can be used even for
   time stamps that would not otherwise be valid, e.g., GMT time
   stamps in 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 getdate 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) },	/* Newfoundland Standard */
  { "NDT",	tDAYZONE,-(HOUR ( 3) + 30) },	/* 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) },	/* 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. */
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", 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, 0, 0 }
};



/* Convert a time zone expressed as HH:MM into an integer count of
   minutes.  If MM is negative, then S is of the form HHMM and needs
   to be picked apart; otherwise, S is of the form HH.  */

static long int
time_zone_hhmm (textint s, long int mm)
{
  if (mm < 0)
    return (s.value / 100) * 60 + s.value % 100;
  else
    return s.value * 60 + (s.negative ? -mm : mm);
}

static int
to_hour (long int 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;
    }
}

static long int
to_year (textint textyear)
{
  long 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.  */
  else if (textyear.digits == 2)
    year += year < 69 ? 2000 : 1900;

  return year;
}

static table const *
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 src/strftime.c.  */
static long int
tm_diff (struct tm const *a, struct tm const *b)
{
  /* Compute intervening leap days correctly even if year is negative.
     Take care to avoid int overflow in leap day calculations.  */
  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);
  long int ayear = a->tm_year;
  long int years = ayear - b->tm_year;
  long 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;
  size_t wordlen;
  table const *tp;
  bool period_found;
  bool abbrev;

  /* Make it uppercase.  */
  for (p = word; *p; p++)
    {
      unsigned char ch = *p;
      *p = toupper (ch);
    }

  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 (YYSTYPE *lvalp, parser_control *pc)
{
  unsigned char c;
  size_t count;

  for (;;)
    {
      while (c = *pc->input, isspace (c))
	pc->input++;

      if (ISDIGIT (c) || c == '-' || c == '+')
	{
	  char const *p;
	  int sign;
	  unsigned long int value;
	  if (c == '-' || c == '+')
	    {
	      sign = c == '-' ? -1 : 1;
	      while (c = *++pc->input, isspace (c))
		continue;
	      if (! ISDIGIT (c))
		/* skip the '-' sign */
		continue;
	    }
	  else
	    sign = 0;
	  p = pc->input;
	  for (value = 0; ; value *= 10)
	    {
	      unsigned long int value1 = value + (c - '0');
	      if (value1 < value)
		return '?';
	      value = value1;
	      c = *++p;
	      if (! ISDIGIT (c))
		break;
	      if (ULONG_MAX / 10 < value)
		return '?';
	    }
	  if ((c == '.' || c == ',') && ISDIGIT (p[1]))
	    {
	      time_t s;
	      int ns;
	      int digits;
	      unsigned long int value1;

	      /* Check for overflow when converting value to time_t.  */
	      if (sign < 0)
		{
		  s = - value;
		  if (0 < s)
		    return '?';
		  value1 = -s;
		}
	      else
		{
		  s = value;
		  if (s < 0)
		    return '?';
		  value1 = s;
		}