[tz] Troll throws zic for a loop
Paul Eggert
eggert at cs.ucla.edu
Fri Mar 21 03:12:15 UTC 2014
Zefram wrote:
> Attached patch implements. I didn't touch localtime.c yet.
Thanks for looking into it; that helps quite a bit.
I'm reluctant to have localtime.c invoke malloc, since that'd be a new
way for localtime to fail; it's purposely designed to not malloc unless
the builder #defines ALL_STATE. If mad scientists in Antarctica keep
cooking up new ways to tell time we may have to do something more
drastic, but for now bumping TZ_MAX_TIMES a bit should be a relatively
painless way forward.
The new Antarctica/Troll entry would be rejected by current 'zic'
implementations, so it may be prudent to comment it out at first, and
let the new 'zic' propagate for a bit, before uncommenting it in a later
relese.
As you mention, if Antarctica/Troll is built by a new 'zic', GNU/Linux
will operate correctly on it but 2014a-or-earlier localtime will
silently treat it as if it were UTC. I have verified that Solaris 11
localtime has similar problems, and I expect other implementations will
too. As the issue is limited to one small station in Antarctica I
suppose it's not a big deal.
For now I installed the attached patches to the experimental version on
github. These should fix the bugs mentioned in this area, along with
some further gotchas that I noticed will reviewing and improving the
patches. Further comments welcome.
-------------- next part --------------
From 45badd3cb0a0561ed4ff80d8715dc491f21b2012 Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert at cs.ucla.edu>
Date: Thu, 20 Mar 2014 13:35:02 -0700
Subject: [PATCH 1/6] Fix overallocation problem in zic.
* zic.c (writezone), NEWS: Give 'writetype' TX_MAX_TYPES entries,
not TZ_MAX_TIMES. (Thanks to Zefram.)
---
NEWS | 5 +++++
zic.c | 2 +-
2 files changed, 6 insertions(+), 1 deletion(-)
diff --git a/NEWS b/NEWS
index 0214ca3..13b40dc 100644
--- a/NEWS
+++ b/NEWS
@@ -8,6 +8,11 @@ Unreleased, experimental changes
Crimea switches to Moscow time on 2014-03-30 at 02:00 local time.
(Thanks to Alexander Krivenyshev.) Move its zone.tab entry from UA to RU.
+ Changes affecting 'zic'
+
+ 'zic' now is smarter about allocating memory.
+ (Thanks to Andrew Main (Zefram).)
+
Changes affecting commentary and documentation
Fix Tuesday/Thursday typo in description of time in Israel.
diff --git a/zic.c b/zic.c
index e7b0081..bd388d3 100644
--- a/zic.c
+++ b/zic.c
@@ -1539,7 +1539,7 @@ writezone(const char *const name, const char *const string, char version)
register int thistimei, thistimecnt;
register int thisleapi, thisleapcnt;
register int thistimelim, thisleaplim;
- int writetype[TZ_MAX_TIMES];
+ int writetype[TZ_MAX_TYPES];
int typemap[TZ_MAX_TYPES];
register int thistypecnt;
char thischars[TZ_MAX_CHARS];
--
1.8.5.3
-------------- next part --------------
From f3ea6c6f8491d8f6cd1042b7dde356d886462f77 Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert at cs.ucla.edu>
Date: Thu, 20 Mar 2014 14:34:32 -0700
Subject: [PATCH 2/6] Check for integer overflow errors in zic.
Also, allocate memory faster by growing buffers by a factor of 1.5
each time, rather than simply adding 1 to the size.
* private.h (SIZE_MAX): New macro, for older systems lacking it.
* zic.c (nrules_alloc, nzones_alloc, nlinks_alloc): New static vars.
(memory_exhausted, size_product, growalloc): New functions.
(memcheck, inrule, inzsub, inlink, getfields): Use them.
---
private.h | 4 ++++
zic.c | 49 ++++++++++++++++++++++++++++++++++++++-----------
2 files changed, 42 insertions(+), 11 deletions(-)
diff --git a/private.h b/private.h
index 4eb0ab6..1a85c88 100644
--- a/private.h
+++ b/private.h
@@ -205,6 +205,10 @@ typedef unsigned long uintmax_t;
#define INT32_MIN (-1 - INT32_MAX)
#endif /* !defined INT32_MIN */
+#ifndef SIZE_MAX
+#define SIZE_MAX ((size_t) -1)
+#endif
+
#if 2 < __GNUC__ + (96 <= __GNUC_MINOR__)
# define ATTRIBUTE_CONST __attribute__ ((const))
# define ATTRIBUTE_PURE __attribute__ ((__pure__))
diff --git a/zic.c b/zic.c
index bd388d3..d2a846c 100644
--- a/zic.c
+++ b/zic.c
@@ -247,9 +247,11 @@ static int typecnt;
static struct rule * rules;
static int nrules; /* number of rules */
+static int nrules_alloc;
static struct zone * zones;
static int nzones; /* number of zones */
+static int nzones_alloc;
struct link {
const char * l_filename;
@@ -260,6 +262,7 @@ struct link {
static struct link * links;
static int nlinks;
+static int nlinks_alloc;
struct lookup {
const char * l_word;
@@ -361,16 +364,26 @@ static char roll[TZ_MAX_LEAPS];
** Memory allocation.
*/
+static _Noreturn void
+memory_exhausted(const char *msg)
+{
+ fprintf(stderr, _("%s: Memory exhausted: %s\n"), progname, msg);
+ exit(EXIT_FAILURE);
+}
+
+static ATTRIBUTE_PURE size_t
+size_product(size_t nitems, size_t itemsize)
+{
+ if (SIZE_MAX / itemsize < nitems)
+ memory_exhausted("size overflow");
+ return nitems * itemsize;
+}
+
static ATTRIBUTE_PURE void *
memcheck(void *const ptr)
{
- if (ptr == NULL) {
- const char *e = strerror(errno);
-
- (void) fprintf(stderr, _("%s: Memory exhausted: %s\n"),
- progname, e);
- exit(EXIT_FAILURE);
- }
+ if (ptr == NULL)
+ memory_exhausted(strerror(errno));
return ptr;
}
@@ -379,6 +392,20 @@ memcheck(void *const ptr)
#define ecpyalloc(ptr) memcheck(icpyalloc(ptr))
#define ecatalloc(oldp, newp) memcheck(icatalloc((oldp), (newp)))
+static void *
+growalloc(void *ptr, size_t itemsize, int nitems, int *nitems_alloc)
+{
+ if (nitems < *nitems_alloc)
+ return ptr;
+ else {
+ int amax = INT_MAX < SIZE_MAX ? INT_MAX : SIZE_MAX;
+ if ((amax - 1) / 2 < *nitems_alloc)
+ memory_exhausted("int ooverflow");
+ *nitems_alloc = *nitems_alloc + (*nitems_alloc >> 1) + 1;
+ return erealloc(ptr, size_product(*nitems_alloc, itemsize));
+ }
+}
+
/*
** Error handling.
*/
@@ -965,7 +992,7 @@ inrule(register char **const fields, const int nfields)
r.r_abbrvar = ecpyalloc(fields[RF_ABBRVAR]);
if (max_abbrvar_len < strlen(r.r_abbrvar))
max_abbrvar_len = strlen(r.r_abbrvar);
- rules = erealloc(rules, (nrules + 1) * sizeof *rules);
+ rules = growalloc(rules, sizeof *rules, nrules, &nrules_alloc);
rules[nrules++] = r;
}
@@ -1081,7 +1108,7 @@ inzsub(register char **const fields, const int nfields, const int iscont)
return FALSE;
}
}
- zones = erealloc(zones, (nzones + 1) * sizeof *zones);
+ zones = growalloc(zones, sizeof *zones, nzones, &nzones_alloc);
zones[nzones++] = z;
/*
** If there was an UNTIL field on this line,
@@ -1214,7 +1241,7 @@ inlink(register char **const fields, const int nfields)
l.l_linenum = linenum;
l.l_from = ecpyalloc(fields[LF_FROM]);
l.l_to = ecpyalloc(fields[LF_TO]);
- links = erealloc(links, (nlinks + 1) * sizeof *links);
+ links = growalloc(links, sizeof *links, nlinks, &nlinks_alloc);
links[nlinks++] = l;
}
@@ -2572,7 +2599,7 @@ getfields(register char *cp)
if (cp == NULL)
return NULL;
- array = emalloc((strlen(cp) + 1) * sizeof *array);
+ array = emalloc(size_product(strlen(cp) + 1, sizeof *array));
nsubs = 0;
for ( ; ; ) {
while (isascii((unsigned char) *cp) &&
--
1.8.5.3
-------------- next part --------------
From 725779ad2ff887e6f137a74e806193fd92615e08 Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert at cs.ucla.edu>
Date: Thu, 20 Mar 2014 18:11:23 -0700
Subject: [PATCH 3/6] Remove TZ_MAX_TIMES restriction in zic.c.
This lets zic handle the time rules of Troll station,
Antarctica. Adapted from a fix by Zefram in:
http://mm.icann.org/pipermail/tz/2014-March/020759.html
* zic.c (timecnt_alloc): New static var.
(attypes): Now a pointer to an array, not a fixed size array.
(writezone, addtt): Don't assume the number of times is less than
TZ_MAX_TIMES.
* NEWS: Document this.
---
NEWS | 6 ++++--
zic.c | 14 +++++++-------
2 files changed, 11 insertions(+), 9 deletions(-)
diff --git a/NEWS b/NEWS
index 13b40dc..351058d 100644
--- a/NEWS
+++ b/NEWS
@@ -10,8 +10,10 @@ Unreleased, experimental changes
Changes affecting 'zic'
- 'zic' now is smarter about allocating memory.
- (Thanks to Andrew Main (Zefram).)
+ 'zic' no longer rejects locations needing four transitions per
+ year for the forseeable future, such as Troll station, Antarctica.
+ (Thanks to Andrew Main (Zefram).) Also, it avoids some unlikely
+ failures due to integer overflow.
Changes affecting commentary and documentation
diff --git a/zic.c b/zic.c
index d2a846c..09fda7a 100644
--- a/zic.c
+++ b/zic.c
@@ -162,6 +162,7 @@ static const char * rfilename;
static int rlinenum;
static const char * progname;
static int timecnt;
+static int timecnt_alloc;
static int typecnt;
/*
@@ -349,7 +350,7 @@ static const int len_years[2] = {
static struct attype {
zic_t at;
unsigned char type;
-} attypes[TZ_MAX_TIMES];
+} * attypes;
static zic_t gmtoffs[TZ_MAX_TYPES];
static char isdsts[TZ_MAX_TYPES];
static unsigned char abbrinds[TZ_MAX_TYPES];
@@ -1461,8 +1462,9 @@ writezone(const char *const name, const char *const string, char version)
static char * fullname;
static const struct tzhead tzh0;
static struct tzhead tzh;
- zic_t ats[TZ_MAX_TIMES];
- unsigned char types[TZ_MAX_TIMES];
+ zic_t *ats = emalloc(size_product(timecnt, sizeof *ats + 1));
+ void *typesptr = ats + timecnt;
+ unsigned char *types = typesptr;
/*
** Sort.
@@ -1778,6 +1780,7 @@ writezone(const char *const name, const char *const string, char version)
progname, fullname);
exit(EXIT_FAILURE);
}
+ free(ats);
}
static void
@@ -2397,10 +2400,7 @@ addtt(const zic_t starttime, int type)
timecnt = 0;
type = 0;
}
- if (timecnt >= TZ_MAX_TIMES) {
- error(_("too many transitions?!"));
- exit(EXIT_FAILURE);
- }
+ attypes = growalloc(attypes, sizeof *attypes, timecnt, &timecnt_alloc);
attypes[timecnt].at = starttime;
attypes[timecnt].type = type;
++timecnt;
--
1.8.5.3
-------------- next part --------------
From a3129e54ee09d5968b62a896717aaa7092cafeee Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert at cs.ucla.edu>
Date: Thu, 20 Mar 2014 18:39:12 -0700
Subject: [PATCH 4/6] * tzfile.h (TZ_MAX_TIMES), NEWS: Increase from 1200 to
2000.
This lets localtime handle Troll station. Hack suggested by Zefram.
---
NEWS | 9 ++++-----
tzfile.h | 2 +-
2 files changed, 5 insertions(+), 6 deletions(-)
diff --git a/NEWS b/NEWS
index 351058d..7924e3a 100644
--- a/NEWS
+++ b/NEWS
@@ -8,12 +8,11 @@ Unreleased, experimental changes
Crimea switches to Moscow time on 2014-03-30 at 02:00 local time.
(Thanks to Alexander Krivenyshev.) Move its zone.tab entry from UA to RU.
- Changes affecting 'zic'
+ Changes affecting code
- 'zic' no longer rejects locations needing four transitions per
- year for the forseeable future, such as Troll station, Antarctica.
- (Thanks to Andrew Main (Zefram).) Also, it avoids some unlikely
- failures due to integer overflow.
+ 'zic' and 'localtime' no longer reject locations needing four transitions
+ per year for the forseeable future. (Thanks to Andrew Main (Zefram).)
+ Also, 'zic' avoids some unlikely failures due to integer overflow.
Changes affecting commentary and documentation
diff --git a/tzfile.h b/tzfile.h
index 529650d..911130e 100644
--- a/tzfile.h
+++ b/tzfile.h
@@ -97,7 +97,7 @@ struct tzhead {
*/
#ifndef TZ_MAX_TIMES
-#define TZ_MAX_TIMES 1200
+#define TZ_MAX_TIMES 2000
#endif /* !defined TZ_MAX_TIMES */
#ifndef TZ_MAX_TYPES
--
1.8.5.3
-------------- next part --------------
From 440c8dbcca60fe5ab9812425d28251098d4e85ee Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert at cs.ucla.edu>
Date: Thu, 20 Mar 2014 18:48:46 -0700
Subject: [PATCH 5/6] * antarctica, NEWS: Add a commented-out entry for Troll
station.
(Thanks to Paul-Inge Flakstad.)
---
NEWS | 5 +++++
antarctica | 25 +++++++++++++++++++++++++
2 files changed, 30 insertions(+)
diff --git a/NEWS b/NEWS
index 7924e3a..c33c214 100644
--- a/NEWS
+++ b/NEWS
@@ -16,6 +16,11 @@ Unreleased, experimental changes
Changes affecting commentary and documentation
+ Add a commented-out entry for Troll station, Antarctica.
+ (Thanks to Paul-Inge Flakstad.) It requires the 'zic' and 'localtime'
+ fixes mentioned above, so the plan is to wait for a while until these
+ fixes propagate.
+
Fix Tuesday/Thursday typo in description of time in Israel.
(Thanks to Bert Katz via Pavel Kharitonov and Mike Frysinger.)
diff --git a/antarctica b/antarctica
index 5333b7b..2e0806c 100644
--- a/antarctica
+++ b/antarctica
@@ -248,6 +248,31 @@ Rule NZAQ 2008 max - Apr Sun>=1 2:00s 0 S
#
# claims
# Peter I Island (never inhabited)
+#
+# year-round base
+# Troll, Jutulsessen, -720041+0023206, since 2005-02-11
+#
+# From Paul-Inge Flakstad (2014-03-10):
+# I recently had a long dialog about this with the developer of timegenie.com.
+# In the absence of specific dates, he decided to choose some likely ones:
+# GMT +1 — From March 1 to the last Sunday in March
+# GMT +2 — From the last Sunday in March until the last Sunday in October
+# GMT +1 — From the last Sunday in October until November 7
+# GMT +0 — From November 7 until March 1
+# The dates for switching to and from UTC+0 will probably not be absolutely
+# correct, but they should be quite close to the actual dates.
+#
+# From Paul Eggert (2014-03-20):
+# This entry requires tzcode 2014b or later, so comment it out for now.
+# Uncomment it when 2014b is supported in more places.
+## Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
+#Rule Troll 2005 max - Mar 1 1:00u 1:00 CET
+#Rule Troll 2005 max - Mar lastSun 1:00u 2:00 CEST
+#Rule Troll 2005 max - Oct lastSun 1:00u 1:00 CET
+#Rule Troll 2004 max - Nov 7 1:00u 0:00 UTC
+## Zone NAME GMTOFF RULES FORMAT [UNTIL]
+#Zone Antarctica/Troll 0 - zzz 2005 Feb 11
+# 0:00 Troll %s
# Poland - year-round base
# Arctowski, King George Island, -620945-0582745, since 1977
--
1.8.5.3
-------------- next part --------------
From b979bceed1f14619df7b3331e1a7247dcbe87815 Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert at cs.ucla.edu>
Date: Thu, 20 Mar 2014 19:01:21 -0700
Subject: [PATCH 6/6] Remove unused rules, and add a check for this.
* checktab.awk: Check for a Rule defined but never used.
* antarctica (NZAQ): Remove unused rule.
* NEWS: Document this.
---
NEWS | 5 +++++
antarctica | 12 ------------
checktab.awk | 20 +++++++++++++++++---
3 files changed, 22 insertions(+), 15 deletions(-)
diff --git a/NEWS b/NEWS
index c33c214..4b53037 100644
--- a/NEWS
+++ b/NEWS
@@ -14,6 +14,11 @@ Unreleased, experimental changes
per year for the forseeable future. (Thanks to Andrew Main (Zefram).)
Also, 'zic' avoids some unlikely failures due to integer overflow.
+ Changes affecting build procedure
+
+ 'make check' now detects Rule lines defined but never used.
+ The NZAQ rules, an instance of this problem, have been removed.
+
Changes affecting commentary and documentation
Add a commented-out entry for Troll station, Antarctica.
diff --git a/antarctica b/antarctica
index 2e0806c..06da875 100644
--- a/antarctica
+++ b/antarctica
@@ -230,18 +230,6 @@ Zone Antarctica/Syowa 0 - zzz 1957 Jan 29
# year-round base
# Scott Base, Ross Island, since 1957-01.
# See Pacific/Auckland.
-#
-# These rules for New Zealand are stolen from the 'australasia' file.
-# Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S
-Rule NZAQ 1974 only - Nov 3 2:00s 1:00 D
-Rule NZAQ 1975 1988 - Oct lastSun 2:00s 1:00 D
-Rule NZAQ 1989 only - Oct 8 2:00s 1:00 D
-Rule NZAQ 1990 2006 - Oct Sun>=1 2:00s 1:00 D
-Rule NZAQ 1975 only - Feb 23 2:00s 0 S
-Rule NZAQ 1976 1989 - Mar Sun>=1 2:00s 0 S
-Rule NZAQ 1990 2007 - Mar Sun>=15 2:00s 0 S
-Rule NZAQ 2007 max - Sep lastSun 2:00s 1:00 D
-Rule NZAQ 2008 max - Apr Sun>=1 2:00s 0 S
# Norway - territories
# Bouvet (never inhabited)
diff --git a/checktab.awk b/checktab.awk
index fec4f62..d78ba73 100644
--- a/checktab.awk
+++ b/checktab.awk
@@ -115,10 +115,14 @@ BEGIN {
FS = " "
}
+$1 ~ /^#/ { next }
+
{
- tz = ""
- if ($1 == "Zone") tz = $2
- if ($1 == "Link") {
+ tz = rules = ""
+ if ($1 == "Zone") {
+ tz = $2
+ ruleUsed[$4] = 1
+ } else if ($1 == "Link") {
# Ignore Link commands if source and destination basenames
# are identical, e.g. Europe/Istanbul versus Asia/Istanbul.
src = $2
@@ -126,6 +130,10 @@ BEGIN {
while ((i = index(src, "/"))) src = substr(src, i+1)
while ((i = index(dst, "/"))) dst = substr(dst, i+1)
if (src != dst) tz = $3
+ } else if ($1 == "Rule") {
+ ruleDefined[$2] = 1
+ } else {
+ ruleUsed[$2] = 1
}
if (tz && tz ~ /\//) {
if (!tztab[tz]) {
@@ -138,6 +146,12 @@ BEGIN {
}
END {
+ for (tz in ruleDefined) {
+ if (!ruleUsed[tz]) {
+ printf "%s: Rule never used\n", tz
+ status = 1
+ }
+ }
for (tz in tz2cc) {
if (!zoneSeen[tz]) {
printf "%s:%d: no Zone table for `%s'\n", \
--
1.8.5.3
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