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