/* Convert a broken-down timestamp to a string. */ /* * Copyright 1989 The Regents of the University of California. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS" AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * Based on the UCB version with the copyright notice appearing above. * * This is ANSIish only when "multibyte character == plain character". * * IDENTIFICATION * src/timezone/strftime.c */ #include "postgres.h" #include #include "private.h" struct lc_time_T { const char *mon[MONSPERYEAR]; const char *month[MONSPERYEAR]; const char *wday[DAYSPERWEEK]; const char *weekday[DAYSPERWEEK]; const char *X_fmt; const char *x_fmt; const char *c_fmt; const char *am; const char *pm; const char *date_fmt; }; #define Locale (&C_time_locale) static const struct lc_time_T C_time_locale = { { "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" }, { "January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December" }, { "Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" }, { "Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday" }, /* X_fmt */ "%H:%M:%S", /* * x_fmt * * C99 and later require this format. Using just numbers (as here) makes * Quakers happier; it's also compatible with SVR4. */ "%m/%d/%y", /* * c_fmt * * C99 and later require this format. Previously this code used "%D %X", * but we now conform to C99. Note that "%a %b %d %H:%M:%S %Y" is used by * Solaris 2.3. */ "%a %b %e %T %Y", /* am */ "AM", /* pm */ "PM", /* date_fmt */ "%a %b %e %H:%M:%S %Z %Y" }; enum warn { IN_NONE, IN_SOME, IN_THIS, IN_ALL }; static char *_add(const char *, char *, const char *); static char *_conv(int, const char *, char *, const char *); static char *_fmt(const char *, const struct pg_tm *, char *, const char *, enum warn *); static char *_yconv(int, int, bool, bool, char *, char const *); /* * Convert timestamp t to string s, a caller-allocated buffer of size maxsize, * using the given format pattern. * * See also timestamptz_to_str. */ size_t pg_strftime(char *s, size_t maxsize, const char *format, const struct pg_tm *t) { char *p; int saved_errno = errno; enum warn warn = IN_NONE; p = _fmt(format, t, s, s + maxsize, &warn); if (!p) { errno = EOVERFLOW; return 0; } if (p == s + maxsize) { errno = ERANGE; return 0; } *p = '\0'; errno = saved_errno; return p - s; } static char * _fmt(const char *format, const struct pg_tm *t, char *pt, const char *ptlim, enum warn *warnp) { for (; *format; ++format) { if (*format == '%') { label: switch (*++format) { case '\0': --format; break; case 'A': pt = _add((t->tm_wday < 0 || t->tm_wday >= DAYSPERWEEK) ? "?" : Locale->weekday[t->tm_wday], pt, ptlim); continue; case 'a': pt = _add((t->tm_wday < 0 || t->tm_wday >= DAYSPERWEEK) ? "?" : Locale->wday[t->tm_wday], pt, ptlim); continue; case 'B': pt = _add((t->tm_mon < 0 || t->tm_mon >= MONSPERYEAR) ? "?" : Locale->month[t->tm_mon], pt, ptlim); continue; case 'b': case 'h': pt = _add((t->tm_mon < 0 || t->tm_mon >= MONSPERYEAR) ? "?" : Locale->mon[t->tm_mon], pt, ptlim); continue; case 'C': /* * %C used to do a... _fmt("%a %b %e %X %Y", t); * ...whereas now POSIX 1003.2 calls for something * completely different. (ado, 1993-05-24) */ pt = _yconv(t->tm_year, TM_YEAR_BASE, true, false, pt, ptlim); continue; case 'c': { enum warn warn2 = IN_SOME; pt = _fmt(Locale->c_fmt, t, pt, ptlim, &warn2); if (warn2 == IN_ALL) warn2 = IN_THIS; if (warn2 > *warnp) *warnp = warn2; } continue; case 'D': pt = _fmt("%m/%d/%y", t, pt, ptlim, warnp); continue; case 'd': pt = _conv(t->tm_mday, "%02d", pt, ptlim); continue; case 'E': case 'O': /* * Locale modifiers of C99 and later. The sequences %Ec * %EC %Ex %EX %Ey %EY %Od %oe %OH %OI %Om %OM %OS %Ou %OU * %OV %Ow %OW %Oy are supposed to provide alternative * representations. */ goto label; case 'e': pt = _conv(t->tm_mday, "%2d", pt, ptlim); continue; case 'F': pt = _fmt("%Y-%m-%d", t, pt, ptlim, warnp); continue; case 'H': pt = _conv(t->tm_hour, "%02d", pt, ptlim); continue; case 'I': pt = _conv((t->tm_hour % 12) ? (t->tm_hour % 12) : 12, "%02d", pt, ptlim); continue; case 'j': pt = _conv(t->tm_yday + 1, "%03d", pt, ptlim); continue; case 'k': /* * This used to be... _conv(t->tm_hour % 12 ? t->tm_hour % * 12 : 12, 2, ' '); ...and has been changed to the below * to match SunOS 4.1.1 and Arnold Robbins' strftime * version 3.0. That is, "%k" and "%l" have been swapped. * (ado, 1993-05-24) */ pt = _conv(t->tm_hour, "%2d", pt, ptlim); continue; #ifdef KITCHEN_SINK case 'K': /* * After all this time, still unclaimed! */ pt = _add("kitchen sink", pt, ptlim); continue; #endif /* defined KITCHEN_SINK */ case 'l': /* * This used to be... _conv(t->tm_hour, 2, ' '); ...and * has been changed to the below to match SunOS 4.1.1 and * Arnold Robbin's strftime version 3.0. That is, "%k" and * "%l" have been swapped. (ado, 1993-05-24) */ pt = _conv((t->tm_hour % 12) ? (t->tm_hour % 12) : 12, "%2d", pt, ptlim); continue; case 'M': pt = _conv(t->tm_min, "%02d", pt, ptlim); continue; case 'm': pt = _conv(t->tm_mon + 1, "%02d", pt, ptlim); continue; case 'n': pt = _add("\n", pt, ptlim); continue; case 'p': pt = _add((t->tm_hour >= (HOURSPERDAY / 2)) ? Locale->pm : Locale->am, pt, ptlim); continue; case 'R': pt = _fmt("%H:%M", t, pt, ptlim, warnp); continue; case 'r': pt = _fmt("%I:%M:%S %p", t, pt, ptlim, warnp); continue; case 'S': pt = _conv(t->tm_sec, "%02d", pt, ptlim); continue; case 'T': pt = _fmt("%H:%M:%S", t, pt, ptlim, warnp); continue; case 't': pt = _add("\t", pt, ptlim); continue; case 'U': pt = _conv((t->tm_yday + DAYSPERWEEK - t->tm_wday) / DAYSPERWEEK, "%02d", pt, ptlim); continue; case 'u': /* * From Arnold Robbins' strftime version 3.0: "ISO 8601: * Weekday as a decimal number [1 (Monday) - 7]" (ado, * 1993-05-24) */ pt = _conv((t->tm_wday == 0) ? DAYSPERWEEK : t->tm_wday, "%d", pt, ptlim); continue; case 'V': /* ISO 8601 week number */ case 'G': /* ISO 8601 year (four digits) */ case 'g': /* ISO 8601 year (two digits) */ /* * From Arnold Robbins' strftime version 3.0: "the week number of the * year (the first Monday as the first day of week 1) as a decimal number * (01-53)." * (ado, 1993-05-24) * * From by Markus Kuhn: * "Week 01 of a year is per definition the first week which has the * Thursday in this year, which is equivalent to the week which contains * the fourth day of January. In other words, the first week of a new year * is the week which has the majority of its days in the new year. Week 01 * might also contain days from the previous year and the week before week * 01 of a year is the last week (52 or 53) of the previous year even if * it contains days from the new year. A week starts with Monday (day 1) * and ends with Sunday (day 7). For example, the first week of the year * 1997 lasts from 1996-12-30 to 1997-01-05..." * (ado, 1996-01-02) */ { int year; int base; int yday; int wday; int w; year = t->tm_year; base = TM_YEAR_BASE; yday = t->tm_yday; wday = t->tm_wday; for (;;) { int len; int bot; int top; len = isleap_sum(year, base) ? DAYSPERLYEAR : DAYSPERNYEAR; /* * What yday (-3 ... 3) does the ISO year begin * on? */ bot = ((yday + 11 - wday) % DAYSPERWEEK) - 3; /* * What yday does the NEXT ISO year begin on? */ top = bot - (len % DAYSPERWEEK); if (top < -3) top += DAYSPERWEEK; top += len; if (yday >= top) { ++base; w = 1; break; } if (yday >= bot) { w = 1 + ((yday - bot) / DAYSPERWEEK); break; } --base; yday += isleap_sum(year, base) ? DAYSPERLYEAR : DAYSPERNYEAR; } if (*format == 'V') pt = _conv(w, "%02d", pt, ptlim); else if (*format == 'g') { *warnp = IN_ALL; pt = _yconv(year, base, false, true, pt, ptlim); } else pt = _yconv(year, base, true, true, pt, ptlim); } continue; case 'v': /* * From Arnold Robbins' strftime version 3.0: "date as * dd-bbb-YYYY" (ado, 1993-05-24) */ pt = _fmt("%e-%b-%Y", t, pt, ptlim, warnp); continue; case 'W': pt = _conv((t->tm_yday + DAYSPERWEEK - (t->tm_wday ? (t->tm_wday - 1) : (DAYSPERWEEK - 1))) / DAYSPERWEEK, "%02d", pt, ptlim); continue; case 'w': pt = _conv(t->tm_wday, "%d", pt, ptlim); continue; case 'X': pt = _fmt(Locale->X_fmt, t, pt, ptlim, warnp); continue; case 'x': { enum warn warn2 = IN_SOME; pt = _fmt(Locale->x_fmt, t, pt, ptlim, &warn2); if (warn2 == IN_ALL) warn2 = IN_THIS; if (warn2 > *warnp) *warnp = warn2; } continue; case 'y': *warnp = IN_ALL; pt = _yconv(t->tm_year, TM_YEAR_BASE, false, true, pt, ptlim); continue; case 'Y': pt = _yconv(t->tm_year, TM_YEAR_BASE, true, true, pt, ptlim); continue; case 'Z': if (t->tm_zone != NULL) pt = _add(t->tm_zone, pt, ptlim); /* * C99 and later say that %Z must be replaced by the empty * string if the time zone abbreviation is not * determinable. */ continue; case 'z': { long diff; char const *sign; bool negative; if (t->tm_isdst < 0) continue; diff = t->tm_gmtoff; negative = diff < 0; if (diff == 0) { if (t->tm_zone != NULL) negative = t->tm_zone[0] == '-'; } if (negative) { sign = "-"; diff = -diff; } else sign = "+"; pt = _add(sign, pt, ptlim); diff /= SECSPERMIN; diff = (diff / MINSPERHOUR) * 100 + (diff % MINSPERHOUR); pt = _conv(diff, "%04d", pt, ptlim); } continue; case '+': pt = _fmt(Locale->date_fmt, t, pt, ptlim, warnp); continue; case '%': /* * X311J/88-090 (4.12.3.5): if conversion char is * undefined, behavior is undefined. Print out the * character itself as printf(3) also does. */ default: break; } } if (pt == ptlim) break; *pt++ = *format; } return pt; } static char * _conv(int n, const char *format, char *pt, const char *ptlim) { char buf[INT_STRLEN_MAXIMUM(int) + 1]; sprintf(buf, format, n); return _add(buf, pt, ptlim); } static char * _add(const char *str, char *pt, const char *ptlim) { while (pt < ptlim && (*pt = *str++) != '\0') ++pt; return pt; } /* * POSIX and the C Standard are unclear or inconsistent about * what %C and %y do if the year is negative or exceeds 9999. * Use the convention that %C concatenated with %y yields the * same output as %Y, and that %Y contains at least 4 bytes, * with more only if necessary. */ static char * _yconv(int a, int b, bool convert_top, bool convert_yy, char *pt, const char *ptlim) { int lead; int trail; #define DIVISOR 100 trail = a % DIVISOR + b % DIVISOR; lead = a / DIVISOR + b / DIVISOR + trail / DIVISOR; trail %= DIVISOR; if (trail < 0 && lead > 0) { trail += DIVISOR; --lead; } else if (lead < 0 && trail > 0) { trail -= DIVISOR; ++lead; } if (convert_top) { if (lead == 0 && trail < 0) pt = _add("-0", pt, ptlim); else pt = _conv(lead, "%02d", pt, ptlim); } if (convert_yy) pt = _conv(((trail < 0) ? -trail : trail), "%02d", pt, ptlim); return pt; }