Zdump for 64-bit systems
Olson, Arthur David (NIH/NCI)
olsona at dc37a.nci.nih.gov
Mon Nov 29 18:07:53 UTC 2004
Below find a version of zdump.c designed to work on systems where time_t is
64 bits.
Some associated changes to other files are to follow in my next message.
--ado
static char elsieid[] = "@(#)zdump.c 7.57";
/*
** This code has been made independent of the rest of the time
** conversion package to increase confidence in the verification it
provides.
** You can use this code to help in verifying other implementations.
*/
#include "stdio.h" /* for stdout, stderr, perror */
#include "string.h" /* for strcpy */
#include "sys/types.h" /* for time_t */
#include "time.h" /* for struct tm */
#include "stdlib.h" /* for exit, malloc, atoi */
#include "float.h" /* for FLT_MAX and DBL_MAX */
#ifndef ZDUMP_LO_YEAR
#define ZDUMP_LO_YEAR (-500)
#endif /* !defined ZDUMP_LO_YEAR */
#ifndef ZDUMP_HI_YEAR
#define ZDUMP_HI_YEAR 2500
#endif /* !defined ZDUMP_HI_YEAR */
#ifndef MAX_STRING_LENGTH
#define MAX_STRING_LENGTH 1024
#endif /* !defined MAX_STRING_LENGTH */
#ifndef TRUE
#define TRUE 1
#endif /* !defined TRUE */
#ifndef FALSE
#define FALSE 0
#endif /* !defined FALSE */
#ifndef EXIT_SUCCESS
#define EXIT_SUCCESS 0
#endif /* !defined EXIT_SUCCESS */
#ifndef EXIT_FAILURE
#define EXIT_FAILURE 1
#endif /* !defined EXIT_FAILURE */
#ifndef SECSPERMIN
#define SECSPERMIN 60
#endif /* !defined SECSPERMIN */
#ifndef MINSPERHOUR
#define MINSPERHOUR 60
#endif /* !defined MINSPERHOUR */
#ifndef SECSPERHOUR
#define SECSPERHOUR (SECSPERMIN * MINSPERHOUR)
#endif /* !defined SECSPERHOUR */
#ifndef HOURSPERDAY
#define HOURSPERDAY 24
#endif /* !defined HOURSPERDAY */
#ifndef EPOCH_YEAR
#define EPOCH_YEAR 1970
#endif /* !defined EPOCH_YEAR */
#ifndef TM_YEAR_BASE
#define TM_YEAR_BASE 1900
#endif /* !defined TM_YEAR_BASE */
#ifndef DAYSPERNYEAR
#define DAYSPERNYEAR 365
#endif /* !defined DAYSPERNYEAR */
#ifndef isleap
#define isleap(y) (((y) % 4) == 0 && (((y) % 100) != 0 || ((y) % 400) == 0))
#endif /* !defined isleap */
#ifndef isleap_sum
/*
** See tzfile.h for details on isleap_sum.
*/
#define isleap_sum(a, b) isleap((a) % 400 + (b) % 400)
#endif /* !defined isleap_sum */
#define SECSPERDAY ((long) SECSPERHOUR * HOURSPERDAY)
#define SECSPERNYEAR (SECSPERDAY * DAYSPERNYEAR)
#define SECSPERLYEAR (SECSPERNYEAR + SECSPERDAY)
#if HAVE_GETTEXT
#include "locale.h" /* for setlocale */
#include "libintl.h"
#endif /* HAVE_GETTEXT */
#ifndef GNUC_or_lint
#ifdef lint
#define GNUC_or_lint
#else /* !defined lint */
#ifdef __GNUC__
#define GNUC_or_lint
#endif /* defined __GNUC__ */
#endif /* !defined lint */
#endif /* !defined GNUC_or_lint */
#ifndef INITIALIZE
#ifdef GNUC_or_lint
#define INITIALIZE(x) ((x) = 0)
#else /* !defined GNUC_or_lint */
#define INITIALIZE(x)
#endif /* !defined GNUC_or_lint */
#endif /* !defined INITIALIZE */
/*
** For the benefit of GNU folk...
** `_(MSGID)' uses the current locale's message library string for MSGID.
** The default is to use gettext if available, and use MSGID otherwise.
*/
#ifndef _
#if HAVE_GETTEXT
#define _(msgid) gettext(msgid)
#else /* !HAVE_GETTEXT */
#define _(msgid) msgid
#endif /* !HAVE_GETTEXT */
#endif /* !defined _ */
#ifndef TZ_DOMAIN
#define TZ_DOMAIN "tz"
#endif /* !defined TZ_DOMAIN */
#ifndef P
#ifdef __STDC__
#define P(x) x
#else /* !defined __STDC__ */
#define P(x) ()
#endif /* !defined __STDC__ */
#endif /* !defined P */
extern char ** environ;
extern int getopt P((int argc, char * const argv[],
const char * options));
extern char * optarg;
extern int optind;
extern char * tzname[2];
static time_t absolute_min_time;
static time_t absolute_max_time;
static size_t longest;
static char * progname;
static char * abbr P((struct tm * tmp));
static long delta P((struct tm * newp, struct tm * oldp));
static void dumptime P((const struct tm * tmp));
static time_t hunt P((char * name, time_t lot, time_t hit));
static void setabsolutes();
static void show P((char * zone, time_t t, int v));
static time_t yeartot P((long y));
int
main(argc, argv)
int argc;
char * argv[];
{
register int i;
register int c;
register int vflag;
register char * cutarg;
register long cutloyear = ZDUMP_LO_YEAR;
register long cuthiyear = ZDUMP_HI_YEAR;
register time_t cutlotime;
register time_t cuthitime;
register char ** fakeenv;
time_t now;
time_t t;
time_t newt;
struct tm tm;
struct tm newtm;
register struct tm * tmp;
register struct tm * newtmp;
INITIALIZE(cutlotime);
INITIALIZE(cuthitime);
#if HAVE_GETTEXT
(void) setlocale(LC_MESSAGES, "");
#ifdef TZ_DOMAINDIR
(void) bindtextdomain(TZ_DOMAIN, TZ_DOMAINDIR);
#endif /* defined TEXTDOMAINDIR */
(void) textdomain(TZ_DOMAIN);
#endif /* HAVE_GETTEXT */
progname = argv[0];
for (i = 1; i < argc; ++i)
if (strcmp(argv[i], "--version") == 0) {
(void) printf("%s\n", elsieid);
(void) exit(EXIT_SUCCESS);
}
vflag = 0;
cutarg = NULL;
while ((c = getopt(argc, argv, "c:v")) == 'c' || c == 'v')
if (c == 'v')
vflag = 1;
else cutarg = optarg;
if ((c != EOF && c != -1) ||
(optind == argc - 1 && strcmp(argv[optind], "=") == 0)) {
(void) fprintf(stderr,
_("%s: usage is %s [ --version ] [ -v ] [ -c [loyear,]hiyear ] zonename
...\n"),
progname, progname);
(void) exit(EXIT_FAILURE);
}
if (vflag) {
if (cutarg != NULL) {
long lo;
long hi;
char c;
if (sscanf(cutarg, "%ld%c", &hi, &c) == 1) {
cuthiyear = hi;
} else if (sscanf(cutarg, "%ld,%ld%c",
&lo, &hi, &c) == 2) {
cutloyear = lo;
cuthiyear = hi;
} else {
(void) fprintf(stderr, _("%s: wild -c argument %s\n"),
progname, cutarg);
(void) exit(EXIT_FAILURE);
}
}
setabsolutes();
cutlotime = yeartot(cutloyear);
cuthitime = yeartot(cuthiyear);
}
(void) time(&now);
longest = 0;
for (i = optind; i < argc; ++i)
if (strlen(argv[i]) > longest)
longest = strlen(argv[i]);
{
register int from;
register int to;
for (i = 0; environ[i] != NULL; ++i)
continue;
fakeenv = (char **) malloc((size_t) ((i + 2) *
sizeof *fakeenv));
if (fakeenv == NULL ||
(fakeenv[0] = (char *) malloc(longest + 4)) == NULL)
{
(void) perror(progname);
(void) exit(EXIT_FAILURE);
}
to = 0;
(void) strcpy(fakeenv[to++], "TZ=");
for (from = 0; environ[from] != NULL; ++from)
if (strncmp(environ[from], "TZ=", 3) != 0)
fakeenv[to++] = environ[from];
fakeenv[to] = NULL;
environ = fakeenv;
}
for (i = optind; i < argc; ++i) {
static char buf[MAX_STRING_LENGTH];
(void) strcpy(&fakeenv[0][3], argv[i]);
if (!vflag) {
show(argv[i], now, FALSE);
continue;
}
t = absolute_min_time;
show(argv[i], t, TRUE);
t += SECSPERHOUR * HOURSPERDAY;
show(argv[i], t, TRUE);
if (t < cutlotime)
t = cutlotime;
tmp = localtime(&t);
if (tmp != NULL) {
tm = *tmp;
(void) strncpy(buf, abbr(&tm), (sizeof buf) - 1);
}
for ( ; ; ) {
if (t >= cuthitime)
break;
newt = t + SECSPERHOUR * 12;
if (newt >= cuthitime)
break;
if (newt <= t)
break;
newtmp = localtime(&newt);
if (newtmp != NULL)
newtm = *newtmp;
if ((tmp == NULL || newtmp == NULL) ? (tmp !=
newtmp) :
(delta(&newtm, &tm) != (newt - t) ||
newtm.tm_isdst != tm.tm_isdst ||
strcmp(abbr(&newtm), buf) != 0)) {
newt = hunt(argv[i], t, newt);
newtmp = localtime(&newt);
if (newtmp != NULL) {
newtm = *newtmp;
(void) strncpy(buf,
abbr(&newtm),
(sizeof buf) - 1);
}
}
t = newt;
tm = newtm;
tmp = newtmp;
}
t = absolute_max_time;
t -= SECSPERHOUR * HOURSPERDAY;
show(argv[i], t, TRUE);
t += SECSPERHOUR * HOURSPERDAY;
show(argv[i], t, TRUE);
}
if (fflush(stdout) || ferror(stdout)) {
(void) fprintf(stderr, "%s: ", progname);
(void) perror(_("Error writing standard output"));
(void) exit(EXIT_FAILURE);
}
exit(EXIT_SUCCESS);
/* If exit fails to exit... */
return EXIT_FAILURE;
}
static void
setabsolutes()
{
if (0.5 == (time_t) 0.5) {
/*
** time_t is floating.
*/
if (sizeof (time_t) == sizeof (float)) {
absolute_min_time = (time_t) -FLT_MAX;
absolute_max_time = (time_t) FLT_MAX;
} else if (sizeof (time_t) == sizeof (double)) {
absolute_min_time = (time_t) -DBL_MAX;
absolute_max_time = (time_t) DBL_MAX;
} else {
(void) fprintf(stderr,
_("%s: use of -v on system with floating time_t other than float or
double\n"),
progname);
(void) exit(EXIT_FAILURE);
}
} else if (0 > (time_t) -1) {
/*
** time_t is signed.
*/
register time_t hibit;
for (hibit = 1; (hibit * 2) != 0; hibit *= 2)
continue;
absolute_min_time = hibit;
absolute_max_time = -(hibit + 1);
} else {
/*
** time_t is unsigned.
*/
absolute_min_time = 0;
absolute_max_time = absolute_min_time - 1;
}
}
static time_t
yeartot(y)
const long y;
{
register long myy;
register long seconds;
register time_t t;
myy = EPOCH_YEAR;
t = 0;
while (myy != y) {
if (myy < y) {
seconds = isleap(myy) ? SECSPERLYEAR : SECSPERNYEAR;
++myy;
if (t > absolute_max_time - seconds) {
t = absolute_max_time;
break;
}
t += seconds;
} else {
--myy;
seconds = isleap(myy) ? SECSPERLYEAR : SECSPERNYEAR;
if (t < absolute_min_time + seconds) {
t = absolute_min_time;
break;
}
t -= seconds;
}
}
return t;
}
static time_t
hunt(name, lot, hit)
char * name;
time_t lot;
time_t hit;
{
time_t t;
long diff;
struct tm lotm;
register struct tm * lotmp;
struct tm tm;
register struct tm * tmp;
char loab[MAX_STRING_LENGTH];
lotmp = localtime(&lot);
if (lotmp != NULL) {
lotm = *lotmp;
(void) strncpy(loab, abbr(&lotm), (sizeof loab) - 1);
}
for ( ; ; ) {
diff = (long) (hit - lot);
if (diff < 2)
break;
t = lot;
t += diff / 2;
if (t <= lot)
++t;
else if (t >= hit)
--t;
tmp = localtime(&t);
if (tmp != NULL)
tm = *tmp;
if ((lotmp == NULL || tmp == NULL) ? (lotmp == tmp) :
(delta(&tm, &lotm) == (t - lot) &&
tm.tm_isdst == lotm.tm_isdst &&
strcmp(abbr(&tm), loab) == 0)) {
lot = t;
lotm = tm;
lotmp = tmp;
} else hit = t;
}
show(name, lot, TRUE);
show(name, hit, TRUE);
return hit;
}
/*
** Thanks to Paul Eggert (eggert at twinsun.com) for logic used in delta.
*/
static long
delta(newp, oldp)
struct tm * newp;
struct tm * oldp;
{
register long result;
register int tmy;
if (newp->tm_year < oldp->tm_year)
return -delta(oldp, newp);
result = 0;
for (tmy = oldp->tm_year; tmy < newp->tm_year; ++tmy)
result += DAYSPERNYEAR + isleap_sum(tmy, TM_YEAR_BASE);
result += newp->tm_yday - oldp->tm_yday;
result *= HOURSPERDAY;
result += newp->tm_hour - oldp->tm_hour;
result *= MINSPERHOUR;
result += newp->tm_min - oldp->tm_min;
result *= SECSPERMIN;
result += newp->tm_sec - oldp->tm_sec;
return result;
}
static void
show(zone, t, v)
char * zone;
time_t t;
int v;
{
register struct tm * tmp;
(void) printf("%-*s ", (int) longest, zone);
if (v) {
tmp = gmtime(&t);
if (tmp == NULL) {
(void) printf("%g", (double) t);
} else {
dumptime(tmp);
(void) printf(" UTC");
}
(void) printf(" = ");
}
tmp = localtime(&t);
dumptime(tmp);
if (tmp != NULL) {
if (*abbr(tmp) != '\0')
(void) printf(" %s", abbr(tmp));
if (v) {
(void) printf(" isdst=%d", tmp->tm_isdst);
#ifdef TM_GMTOFF
(void) printf(" gmtoff=%ld", tmp->TM_GMTOFF);
#endif /* defined TM_GMTOFF */
}
}
(void) printf("\n");
}
static char *
abbr(tmp)
struct tm * tmp;
{
register char * result;
static char nada;
if (tmp->tm_isdst != 0 && tmp->tm_isdst != 1)
return &nada;
result = tzname[tmp->tm_isdst];
return (result == NULL) ? &nada : result;
}
static void
dumptime(timeptr)
register const struct tm * timeptr;
{
static const char wday_name[][3] = {
"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
};
static const char mon_name[][3] = {
"Jan", "Feb", "Mar", "Apr", "May", "Jun",
"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
};
register const char * wn;
register const char * mn;
register int lead;
register int trail;
if (timeptr == NULL) {
(void) printf("NULL");
return;
}
/*
** The packaged versions of localtime and gmtime never put
out-of-range
** values in tm_wday or tm_mon, but since this code might be
compiled
** with other (perhaps experimental) versions, paranoia is in order.
*/
if (timeptr->tm_wday < 0 || timeptr->tm_wday >=
(int) (sizeof wday_name / sizeof wday_name[0]))
wn = "???";
else wn = wday_name[timeptr->tm_wday];
if (timeptr->tm_mon < 0 || timeptr->tm_mon >=
(int) (sizeof mon_name / sizeof mon_name[0]))
mn = "???";
else mn = mon_name[timeptr->tm_mon];
(void) printf("%.3s %.3s%3d %.2d:%.2d:%.2d ",
wn, mn,
timeptr->tm_mday, timeptr->tm_hour,
timeptr->tm_min, timeptr->tm_sec);
#define DIVISOR 10
trail = timeptr->tm_year % DIVISOR + TM_YEAR_BASE % DIVISOR;
lead = timeptr->tm_year / DIVISOR + TM_YEAR_BASE / DIVISOR +
trail / DIVISOR;
trail %= DIVISOR;
if (trail < 0 && lead > 0) {
trail += DIVISOR;
--lead;
} else if (lead < 0 && trail > 0) {
trail -= DIVISOR;
++lead;
}
if (lead == 0)
(void) printf("%d", trail);
else (void) printf("%d%d", lead, ((trail < 0) ? -trail : trail));
}
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