>From 9c32443c5d2a40542c637030323728abb6c350c4 Mon Sep 17 00:00:00 2001 From: Paul Eggert Date: Wed, 4 Jan 2017 23:26:06 -0800 Subject: [PROPOSED] Fix bug in workaround for QTBUG-53071 Problem reported by Bradley White in: http://mm.icann.org/pipermail/tz/2017-January/024724.html * NEWS: Document this. * localtime.c (tzloadbody): Ignore transitions generated due to WORK_AROUND_QTBUG_53071 in zic.c, since they don't help us and may hurt if it is zic 2016j or earlier. * zic.c (outzone): Fill out transitions in 2038, too, so long as they precede the 2**31 boundary. --- NEWS | 6 ++++++ localtime.c | 17 +++++++++++++---- zic.c | 16 ++++++++++++---- 3 files changed, 31 insertions(+), 8 deletions(-) diff --git a/NEWS b/NEWS index 1bd1914..ec1437a 100644 --- a/NEWS +++ b/NEWS @@ -64,6 +64,12 @@ Unreleased, experimental changes Changes to code + zic no longer mishandles some transitions in January 2038 when it + attempts to work around Qt bug 53071. This fixes a bug affecting + Pacific/Tongatapu that was introduced in zic 2016e. localtime.c + now contains a workaround, useful when loading a file generated by + a buggy zic. (Problem reported by Bradley White.) + zdump -i now outputs non-hour numeric time zone abbreviations without a colon, e.g., "+0530" rather than "+05:30". This agrees with zic %z and with common practice, and simplifies auditing of diff --git a/localtime.c b/localtime.c index 3edd1b3..1568aac 100644 --- a/localtime.c +++ b/localtime.c @@ -568,12 +568,12 @@ tzloadbody(char const *name, struct state *sp, bool doextend, && ts->typecnt == 2) { /* Attempt to reuse existing abbreviations. - Without this, America/Anchorage would stop - working after 2037 when TZ_MAX_CHARS is 50, as - sp->charcnt equals 42 (for LMT CAT CAWT CAPT AHST + Without this, America/Anchorage would be right on + the edge after 2037 when TZ_MAX_CHARS is 50, as + sp->charcnt equals 40 (for LMT AST AWT APT AHST AHDT YST AKDT AKST) and ts->charcnt equals 10 (for AKST AKDT). Reusing means sp->charcnt can - stay 42 in this example. */ + stay 40 in this example. */ int gotabbr = 0; int charcnt = sp->charcnt; for (i = 0; i < 2; i++) { @@ -597,6 +597,15 @@ tzloadbody(char const *name, struct state *sp, bool doextend, } if (gotabbr == 2) { sp->charcnt = charcnt; + + /* Ignore any transition that was almost surely + generated because of WORK_AROUND_QTBUG_53071 in + zic.c, as it doesn't help here and can run + afoul of bugs in zic 2016j or earlier. */ + if (1 < sp->timecnt + && sp->ats[sp->timecnt - 1] == 0x7fffffff) + sp->timecnt--; + for (i = 0; i < ts->timecnt; i++) if (sp->ats[sp->timecnt - 1] < ts->ats[i]) break; diff --git a/zic.c b/zic.c index 47c68f9..04798f4 100644 --- a/zic.c +++ b/zic.c @@ -2368,6 +2368,9 @@ outzone(const struct zone *zpfirst, ptrdiff_t zonecount) register bool do_extend; register char version; ptrdiff_t lastatmax = -1; + zic_t one = 1; + zic_t y2038_boundary = one << 31; + zic_t max_year0; max_abbr_len = 2 + max_format_len + max_abbrvar_len; max_envvar_len = 2 * max_abbr_len + 5 * 9; @@ -2463,12 +2466,13 @@ outzone(const struct zone *zpfirst, ptrdiff_t zonecount) } /* ** For the benefit of older systems, - ** generate data from 1900 through 2037. + ** generate data from 1900 through 2038. */ if (min_year > 1900) min_year = 1900; - if (max_year < 2037) - max_year = 2037; + max_year0 = max_year; + if (max_year < 2038) + max_year = 2038; for (i = 0; i < zonecount; ++i) { /* ** A guess that may well be corrected later. @@ -2507,8 +2511,12 @@ outzone(const struct zone *zpfirst, ptrdiff_t zonecount) rp->r_todo = year >= rp->r_loyear && year <= rp->r_hiyear && yearistype(year, rp->r_yrtype); - if (rp->r_todo) + if (rp->r_todo) { rp->r_temp = rpytime(rp, year); + rp->r_todo + = (rp->r_temp < y2038_boundary + || year <= max_year0); + } } for ( ; ; ) { register ptrdiff_t k; -- 2.7.4