This extends the zic input format to add support for %z, which expands to a UTC offset in as-short-as-possible ISO 8601 format. It's intended to better support zones that do not have an established abbreviation already. This is a change only to zic; it does not affect the data, which can still be compiled with older zic versions. * NEWS, zic.8: Document this. * zic.c (struct zone): New member z_format_specifier. (PERCENT_Z_LEN_BOUND): New constant. (max_abbrvar_len): Initialize to it, rather than to 0. (associate, inzsub, doabbr): Add support for %z. (abbroffset): New function. (doabbr): 2nd arg is now struct zone *, not a char *. All callers changed. --- NEWS | 5 +++++ zic.8 | 13 +++++++++++ zic.c | 82 ++++++++++++++++++++++++++++++++++++++++++++++++++++++------------- 3 files changed, 85 insertions(+), 15 deletions(-) diff --git a/NEWS b/NEWS index b7593e7..9eff28c 100644 --- a/NEWS +++ b/NEWS @@ -25,6 +25,11 @@ Unreleased, experimental changes (Thanks to Jon Skeet and Arthur David Olson.) Constraints on simultaneity are now documented. + The two characters '%z' in a zone format now stand for the UTC + offset, e.g., '-07' for seven hours behind UTC and '+0530' for + five hours and thirty minutes ahead. This better supports time + zone abbreviations conforming to POSIX.1-2001 and later. + Changes affecting installed data files Data entries have been simplified for Atlantic/Canary, Europe/Simferopol, diff --git a/zic.8 b/zic.8 index dfb01db..94b6753 100644 --- a/zic.8 +++ b/zic.8 @@ -350,6 +350,19 @@ The pair of characters is used to show where the .q "variable part" of the time zone abbreviation goes. +Alternately, a format can use the pair of characters +.B %z +to stand for the UTC offset in the form +.RI \(+- hh , +.RI \(+- hhmm , +or +.RI \(+- hhmmss , +using the shortest form that does not lose information, where +.IR hh , +.IR mm , +and +.I ss +are the hours, minutes, and seconds east (+) or west (\(mi) of UTC. Alternately, a slash (/) separates standard and daylight abbreviations. diff --git a/zic.c b/zic.c index 6854033..3c4ae93 100644 --- a/zic.c +++ b/zic.c @@ -76,6 +76,7 @@ struct zone { zic_t z_gmtoff; const char * z_rule; const char * z_format; + char z_format_specifier; zic_t z_stdoff; @@ -130,6 +131,9 @@ static void rulesub(struct rule * rp, static zic_t tadd(zic_t t1, zic_t t2); static bool yearistype(int year, const char * type); +/* Bound on length of what %z can expand to. */ +enum { PERCENT_Z_LEN_BOUND = sizeof "+995959" - 1 }; + static int charcnt; static bool errors; static bool warnings; @@ -139,7 +143,7 @@ static bool leapseen; static zic_t leapminyear; static zic_t leapmaxyear; static int linenum; -static int max_abbrvar_len; +static int max_abbrvar_len = PERCENT_Z_LEN_BOUND; static int max_format_len; static zic_t max_year; static zic_t min_year; @@ -955,7 +959,7 @@ associate(void) ** Note, though, that if there's no rule, ** a '%s' in the format is a bad thing. */ - if (strchr(zp->z_format, '%') != 0) + if (zp->z_format_specifier == 's') error("%s", _("%s in ruleless zone")); } } @@ -1170,6 +1174,7 @@ static bool inzsub(char **fields, int nfields, bool iscont) { register char * cp; + char * cp1; static struct zone z; register int i_gmtoff, i_rule, i_format; register int i_untilyear, i_untilmonth; @@ -1201,13 +1206,21 @@ inzsub(char **fields, int nfields, bool iscont) z.z_linenum = linenum; z.z_gmtoff = gethms(fields[i_gmtoff], _("invalid UT offset"), true); if ((cp = strchr(fields[i_format], '%')) != 0) { - if (*++cp != 's' || strchr(cp, '%') != 0) { + if ((*++cp != 's' && *cp != 'z') || strchr(cp, '%') + || strchr(fields[i_format], '/')) { error(_("invalid abbreviation format")); return false; } } z.z_rule = ecpyalloc(fields[i_rule]); - z.z_format = ecpyalloc(fields[i_format]); + z.z_format = cp1 = ecpyalloc(fields[i_format]); + z.z_format_specifier = cp ? *cp : '\0'; + if (z.z_format_specifier == 'z') { + if (noise) + warning(_("format '%s' not handled by pre-2015 versions of zic"), + z.z_format); + cp1[cp - fields[i_format]] = 's'; + } if (max_format_len < strlen(z.z_format)) max_format_len = strlen(z.z_format); hasuntil = nfields > i_untilyear; @@ -1890,19 +1903,59 @@ writezone(const char *const name, const char *const string, char version) free(fullname); } +static char const * +abbroffset(char *buf, zic_t offset) +{ + char sign = '+'; + int seconds, minutes; + + if (offset < 0) { + offset = -offset; + sign = '-'; + } + + seconds = offset % SECSPERMIN; + offset /= SECSPERMIN; + minutes = offset % MINSPERHOUR; + offset /= MINSPERHOUR; + if (100 <= offset) { + error(_("%%z UTC offset magnitude exceeds 99:59:59")); + return "%z"; + } else { + char *p = buf; + *p++ = sign; + *p++ = '0' + offset / 10; + *p++ = '0' + offset % 10; + if (minutes | seconds) { + *p++ = '0' + minutes / 10; + *p++ = '0' + minutes % 10; + if (seconds) { + *p++ = '0' + seconds / 10; + *p++ = '0' + seconds % 10; + } + } + *p = '\0'; + return buf; + } +} + static size_t -doabbr(char *const abbr, const char *const format, const char *const letters, +doabbr(char *abbr, struct zone const *zp, char const *letters, bool isdst, bool doquotes) { register char * cp; register char * slashp; register size_t len; + char const *format = zp->z_format; slashp = strchr(format, '/'); if (slashp == NULL) { - if (letters == NULL) - strcpy(abbr, format); - else sprintf(abbr, format, letters); + char letterbuf[PERCENT_Z_LEN_BOUND + 1]; + if (zp->z_format_specifier == 'z') + letters = abbroffset(letterbuf, -zp->z_gmtoff); + else if (!letters) + letters = "%s"; + sprintf(abbr, format, letters); } else if (isdst) { strcpy(abbr, slashp + 1); } else { @@ -2127,7 +2180,7 @@ stringzone(char *result, const struct zone *const zpfirst, const int zonecount) if (stdrp == NULL && (zp->z_nrules != 0 || zp->z_stdoff != 0)) return -1; abbrvar = (stdrp == NULL) ? "" : stdrp->r_abbrvar; - len = doabbr(result, zp->z_format, abbrvar, false, true); + len = doabbr(result, zp, abbrvar, false, true); offsetlen = stringoffset(result + len, -zp->z_gmtoff); if (! offsetlen) { result[0] = '\0'; @@ -2136,7 +2189,7 @@ stringzone(char *result, const struct zone *const zpfirst, const int zonecount) len += offsetlen; if (dstrp == NULL) return compat; - len += doabbr(result + len, zp->z_format, dstrp->r_abbrvar, true, true); + len += doabbr(result + len, zp, dstrp->r_abbrvar, true, true); if (dstrp->r_stdoff != SECSPERMIN * MINSPERHOUR) { offsetlen = stringoffset(result + len, -(zp->z_gmtoff + dstrp->r_stdoff)); @@ -2307,8 +2360,7 @@ outzone(const struct zone * const zpfirst, const int zonecount) startoff = zp->z_gmtoff; if (zp->z_nrules == 0) { stdoff = zp->z_stdoff; - doabbr(startbuf, zp->z_format, - NULL, stdoff != 0, false); + doabbr(startbuf, zp, NULL, stdoff != 0, false); type = addtype(oadd(zp->z_gmtoff, stdoff), startbuf, stdoff != 0, startttisstd, startttisgmt); @@ -2400,7 +2452,7 @@ outzone(const struct zone * const zpfirst, const int zonecount) if (ktime < starttime) { startoff = oadd(zp->z_gmtoff, stdoff); - doabbr(startbuf, zp->z_format, + doabbr(startbuf, zp, rp->r_abbrvar, rp->r_stdoff != 0, false); @@ -2410,7 +2462,7 @@ outzone(const struct zone * const zpfirst, const int zonecount) startoff == oadd(zp->z_gmtoff, stdoff)) { doabbr(startbuf, - zp->z_format, + zp, rp->r_abbrvar, rp->r_stdoff != false, @@ -2419,7 +2471,7 @@ outzone(const struct zone * const zpfirst, const int zonecount) } eats(zp->z_filename, zp->z_linenum, rp->r_filename, rp->r_linenum); - doabbr(ab, zp->z_format, rp->r_abbrvar, + doabbr(ab, zp, rp->r_abbrvar, rp->r_stdoff != 0, false); offset = oadd(zp->z_gmtoff, rp->r_stdoff); type = addtype(offset, ab, rp->r_stdoff != 0, -- 2.1.4