zic.c

来自「一个C源代码分析器」· C语言 代码 · 共 1,940 行 · 第 1/3 页

			(fwrite_size_t) timecnt, fp);
	for (i = 0; i < typecnt; ++i) {
		puttzcode((long) gmtoffs[i], fp);
		(void) putc(isdsts[i], fp);
		(void) putc(abbrinds[i], fp);
	}
	if (charcnt != 0)
		(void) fwrite((genericptr_t) chars,
			(fwrite_size_t) sizeof chars[0],
			(fwrite_size_t) charcnt, fp);
	for (i = 0; i < leapcnt; ++i) {
		if (roll[i]) {
			if (timecnt == 0 || trans[i] < ats[0]) {
				j = 0;
				while (isdsts[j])
					if (++j >= typecnt) {
						j = 0;
						break;
					}
			} else {
				j = 1;
				while (j < timecnt && trans[i] >= ats[j])
					++j;
				j = types[j - 1];
			}
			puttzcode((long) tadd(trans[i], -gmtoffs[j]), fp);
		} else	puttzcode((long) trans[i], fp);
		puttzcode((long) corr[i], fp);
	}
	for (i = 0; i < typecnt; ++i)
		(void) putc(ttisstds[i], fp);
	if (ferror(fp) || fclose(fp)) {
		(void) fprintf(stderr, "%s: Write error on ", progname);
		(void) perror(fullname);
		(void) exit(EXIT_FAILURE);
	}
}

static void
outzone(zpfirst, zonecount)
const struct zone * const	zpfirst;
const int			zonecount;
{
	register const struct zone *	zp;
	register struct rule *		rp;
	register int			i, j;
	register int			usestart, useuntil;
	register time_t			starttime, untiltime;
	register long			gmtoff;
	register long			stdoff;
	register int			year;
	register long			startoff;
	register int			startisdst;
	register int			startttisstd;
	register int			type;
	char				startbuf[BUFSIZ];

	/*
	** Now. . .finally. . .generate some useful data!
	*/
	timecnt = 0;
	typecnt = 0;
	charcnt = 0;
	/*
	** A guess that may well be corrected later.
	*/
	stdoff = 0;
	/*
	** Thanks to Earl Chew ([e-mail])
	** for noting the need to unconditionally initialize startttisstd.
	*/
	startttisstd = FALSE;
#ifdef lint
	starttime = 0;
#endif /* defined lint */
	for (i = 0; i < zonecount; ++i) {
		zp = &zpfirst[i];
		usestart = i > 0 && (zp - 1)->z_untiltime > min_time;
		useuntil = i < (zonecount - 1);
		if (useuntil && zp->z_untiltime <= min_time)
			continue;
		gmtoff = zp->z_gmtoff;
		eat(zp->z_filename, zp->z_linenum);
		startisdst = -1;
		if (zp->z_nrules == 0) {
			stdoff = zp->z_stdoff;
			(void) strcpy(startbuf, zp->z_format);
			type = addtype(oadd(zp->z_gmtoff, stdoff),
				startbuf, stdoff != 0, startttisstd);
			if (usestart)
				addtt(starttime, type);
			else if (stdoff != 0)
				addtt(min_time, type);
		} else for (year = min_year; year <= max_year; ++year) {
			if (useuntil && year > zp->z_untilrule.r_hiyear)
				break;
			/*
			** Mark which rules to do in the current year.
			** For those to do, calculate rpytime(rp, year);
			*/
			for (j = 0; j < zp->z_nrules; ++j) {
				rp = &zp->z_rules[j];
				eats(zp->z_filename, zp->z_linenum,
					rp->r_filename, rp->r_linenum);
				rp->r_todo = year >= rp->r_loyear &&
						year <= rp->r_hiyear &&
						yearistype(year, rp->r_yrtype);
				if (rp->r_todo)
					rp->r_temp = rpytime(rp, year);
			}
			for ( ; ; ) {
				register int	k;
				register time_t	jtime, ktime;
				register long	offset;
				char		buf[BUFSIZ];

				if (useuntil) {
					/*
					** Turn untiltime into GMT
					** assuming the current gmtoff and
					** stdoff values.
					*/
					untiltime = tadd(zp->z_untiltime,
						-gmtoff);
					if (!zp->z_untilrule.r_todisstd)
						untiltime = tadd(untiltime,
							-stdoff);
				}
				/*
				** Find the rule (of those to do, if any)
				** that takes effect earliest in the year.
				*/
				k = -1;
#ifdef lint
				ktime = 0;
#endif /* defined lint */
				for (j = 0; j < zp->z_nrules; ++j) {
					rp = &zp->z_rules[j];
					if (!rp->r_todo)
						continue;
					eats(zp->z_filename, zp->z_linenum,
						rp->r_filename, rp->r_linenum);
					offset = gmtoff;
					if (!rp->r_todisstd)
						offset = oadd(offset, stdoff);
					jtime = rp->r_temp;
					if (jtime == min_time ||
						jtime == max_time)
							continue;
					jtime = tadd(jtime, -offset);
					if (k < 0 || jtime < ktime) {
						k = j;
						ktime = jtime;
					}
				}
				if (k < 0)
					break;	/* go on to next year */
				rp = &zp->z_rules[k];
				rp->r_todo = FALSE;
				if (useuntil && ktime >= untiltime)
					break;
				if (usestart) {
				    if (ktime < starttime) {
					stdoff = rp->r_stdoff;
					startoff = oadd(zp->z_gmtoff,
						rp->r_stdoff);
					(void) sprintf(startbuf, zp->z_format,
						rp->r_abbrvar);
					startisdst = rp->r_stdoff != 0;
					continue;
				    }
				    usestart = FALSE;
				    if (ktime != starttime) {
					if (startisdst < 0 &&
					    zp->z_gmtoff !=
					    (zp - 1)->z_gmtoff) {
						type = (timecnt == 0) ? 0 :
							types[timecnt - 1];
						startoff = oadd(gmtoffs[type],
							-(zp - 1)->z_gmtoff);
						startisdst = startoff != 0;
						startoff = oadd(startoff,
							zp->z_gmtoff);
						(void) strcpy(startbuf,
							&chars[abbrinds[type]]);
					}
					if (startisdst >= 0)
addtt(starttime, addtype(startoff, startbuf, startisdst, startttisstd));
				    }
				}
				eats(zp->z_filename, zp->z_linenum,
					rp->r_filename, rp->r_linenum);
				(void) sprintf(buf, zp->z_format,
					rp->r_abbrvar);
				offset = oadd(zp->z_gmtoff, rp->r_stdoff);
				type = addtype(offset, buf, rp->r_stdoff != 0,
					rp->r_todisstd);
				addtt(ktime, type);
				stdoff = rp->r_stdoff;
			}
		}
		/*
		** Now we may get to set starttime for the next zone line.
		*/
		if (useuntil) {
			starttime = tadd(zp->z_untiltime, -gmtoff);
			startttisstd = zp->z_untilrule.r_todisstd;
			if (!startttisstd)
				starttime = tadd(starttime, -stdoff);
		}
	}
	writezone(zpfirst->z_name);
}

static void
addtt(starttime, type)
const time_t	starttime;
const int	type;
{
	if (timecnt != 0 && type == types[timecnt - 1])
		return;	/* easy enough! */
	if (timecnt == 0 && type == 0 && isdsts[0] == 0)
		return; /* handled by default rule */
	if (timecnt >= TZ_MAX_TIMES) {
		error("too many transitions?!");
		(void) exit(EXIT_FAILURE);
	}
	ats[timecnt] = starttime;
	types[timecnt] = type;
	++timecnt;
}

static int
addtype(gmtoff, abbr, isdst, ttisstd)
const long		gmtoff;
const char * const	abbr;
const int		isdst;
const int		ttisstd;
{
	register int	i, j;

	/*
	** See if there's already an entry for this zone type.
	** If so, just return its index.
	*/
	for (i = 0; i < typecnt; ++i) {
		if (gmtoff == gmtoffs[i] && isdst == isdsts[i] &&
			strcmp(abbr, &chars[abbrinds[i]]) == 0 &&
			ttisstd == ttisstds[i])
				return i;
	}
	/*
	** There isn't one; add a new one, unless there are already too
	** many.
	*/
	if (typecnt >= TZ_MAX_TYPES) {
		error("too many local time types");
		(void) exit(EXIT_FAILURE);
	}
	gmtoffs[i] = gmtoff;
	isdsts[i] = isdst;
	ttisstds[i] = ttisstd;

	for (j = 0; j < charcnt; ++j)
		if (strcmp(&chars[j], abbr) == 0)
			break;
	if (j == charcnt)
		newabbr(abbr);
	abbrinds[i] = j;
	++typecnt;
	return i;
}

static void
leapadd(t, positive, rolling, count)
const time_t	t;
const int	positive;
const int	rolling;
int		count;
{
	register int	i, j;

	if (leapcnt + (positive ? count : 1) > TZ_MAX_LEAPS) {
		error("too many leap seconds");
		(void) exit(EXIT_FAILURE);
	}
	for (i = 0; i < leapcnt; ++i)
		if (t <= trans[i]) {
			if (t == trans[i]) {
				error("repeated leap second moment");
				(void) exit(EXIT_FAILURE);
			}
			break;
		}
	do {
		for (j = leapcnt; j > i; --j) {
			trans[j] = trans[j - 1];
			corr[j] = corr[j - 1];
			roll[j] = roll[j - 1];
		}
		trans[i] = t;
		corr[i] = positive ? 1L : eitol(-count);
		roll[i] = rolling;
		++leapcnt;
	} while (positive && --count != 0);
}

static void
adjleap()
{
	register int	i;
	register long	last = 0;

	/*
	** propagate leap seconds forward
	*/
	for (i = 0; i < leapcnt; ++i) {
		trans[i] = tadd(trans[i], last);
		last = corr[i] += last;
	}
}

static int
yearistype(year, type)
const int		year;
const char * const	type;
{
	static char *	buf;
	int		result;

	if (type == NULL || *type == '\0')
		return TRUE;
	if (strcmp(type, "uspres") == 0)
		return (year % 4) == 0;
	if (strcmp(type, "nonpres") == 0)
		return (year % 4) != 0;
	buf = erealloc(buf, 132 + strlen(yitcommand) + strlen(type));
	(void) sprintf(buf, "%s %d %s", yitcommand, year, type);
	result = system(buf);
	if (result == 0)
		return TRUE;
	if (result == (1 << 8))
		return FALSE;
	error("Wild result from command execution");
	(void) fprintf(stderr, "%s: command was '%s', result was %d\n",
		progname, buf, result);
	for ( ; ; )
		(void) exit(EXIT_FAILURE);
}

static int
lowerit(a)
const int	a;
{
	return (isascii(a) && isupper(a)) ? tolower(a) : a;
}

static int
ciequal(ap, bp)		/* case-insensitive equality */
register const char *	ap;
register const char *	bp;
{
	while (lowerit(*ap) == lowerit(*bp++))
		if (*ap++ == '\0')
			return TRUE;
	return FALSE;
}

static int
itsabbr(abbr, word)
register const char *	abbr;
register const char *	word;
{
	if (lowerit(*abbr) != lowerit(*word))
		return FALSE;
	++word;
	while (*++abbr != '\0')
		do if (*word == '\0')
			return FALSE;
				while (lowerit(*word++) != lowerit(*abbr));
	return TRUE;
}

static const struct lookup *
byword(word, table)
register const char * const		word;
register const struct lookup * const	table;
{
	register const struct lookup *	foundlp;
	register const struct lookup *	lp;

	if (word == NULL || table == NULL)
		return NULL;
	/*
	** Look for exact match.
	*/
	for (lp = table; lp->l_word != NULL; ++lp)
		if (ciequal(word, lp->l_word))
			return lp;
	/*
	** Look for inexact match.
	*/
	foundlp = NULL;
	for (lp = table; lp->l_word != NULL; ++lp)
		if (itsabbr(word, lp->l_word))
			if (foundlp == NULL)
				foundlp = lp;
			else	return NULL;	/* multiple inexact matches */
	return foundlp;
}

static char **
getfields(cp)
register char *	cp;
{
	register char *		dp;
	register char **	array;
	register int		nsubs;

	if (cp == NULL)
		return NULL;
	array = (char **) emalloc((int) ((strlen(cp) + 1) * sizeof *array));
	nsubs = 0;
	for ( ; ; ) {
		while (isascii(*cp) && isspace(*cp))
			++cp;
		if (*cp == '\0' || *cp == '#')
			break;
		array[nsubs++] = dp = cp;
		do {
			if ((*dp = *cp++) != '"')
				++dp;
			else while ((*dp = *cp++) != '"')
				if (*dp != '\0')
					++dp;
				else	error("Odd number of quotation marks");
		} while (*cp != '\0' && *cp != '#' &&
			(!isascii(*cp) || !isspace(*cp)));
		if (isascii(*cp) && isspace(*cp))
			++cp;
		*dp = '\0';
	}
	array[nsubs] = NULL;
	return array;
}

static long
oadd(t1, t2)
const long	t1;
const long	t2;
{
	register long	t;

	t = t1 + t2;
	if ((t2 > 0 && t <= t1) || (t2 < 0 && t >= t1)) {
		error("time overflow");
		(void) exit(EXIT_FAILURE);
	}
	return t;
}

static time_t
tadd(t1, t2)
const time_t	t1;
const long	t2;
{
	register time_t	t;

	if (t1 == max_time && t2 > 0)
		return max_time;
	if (t1 == min_time && t2 < 0)
		return min_time;
	t = t1 + t2;
	if ((t2 > 0 && t <= t1) || (t2 < 0 && t >= t1)) {
		error("time overflow");
		(void) exit(EXIT_FAILURE);
	}
	return t;
}

/*
** Given a rule, and a year, compute the date - in seconds since January 1,
** 1970, 00:00 LOCAL time - in that year that the rule refers to.
*/

static time_t
rpytime(rp, wantedy)
register const struct rule * const	rp;
register const int			wantedy;
{
	register int	y, m, i;
	register long	dayoff;			/* with a nod to Margaret O. */
	register time_t	t;

	if (wantedy == min_int)
		return min_time;
	if (wantedy == max_int)
		return max_time;
	dayoff = 0;
	m = TM_JANUARY;
	y = EPOCH_YEAR;
	while (wantedy != y) {
		if (wantedy > y) {
			i = len_years[isleap(y)];
			++y;
		} else {
			--y;
			i = -len_years[isleap(y)];
		}
		dayoff = oadd(dayoff, eitol(i));
	}
	while (m != rp->r_month) {
		i = len_months[isleap(y)][m];
		dayoff = oadd(dayoff, eitol(i));
		++m;
	}
	i = rp->r_dayofmonth;
	if (m == TM_FEBRUARY && i == 29 && !isleap(y)) {
		if (rp->r_dycode == DC_DOWLEQ)
			--i;
		else {
			error("use of 2/29 in non leap-year");
			(void) exit(EXIT_FAILURE);
		}
	}
	--i;
	dayoff = oadd(dayoff, eitol(i));
	if (rp->r_dycode == DC_DOWGEQ || rp->r_dycode == DC_DOWLEQ) {
		register long	wday;

#define LDAYSPERWEEK	((long) DAYSPERWEEK)
		wday = eitol(EPOCH_WDAY);
		/*
		** Don't trust mod of negative numbers.
		*/
		if (dayoff >= 0)
			wday = (wday + dayoff) % LDAYSPERWEEK;
		else {
			wday -= ((-dayoff) % LDAYSPERWEEK);
			if (wday < 0)
				wday += LDAYSPERWEEK;
		}
		while (wday != eitol(rp->r_wday))
			if (rp->r_dycode == DC_DOWGEQ) {
				dayoff = oadd(dayoff, (long) 1);
				if (++wday >= LDAYSPERWEEK)
					wday = 0;
				++i;
			} else {
				dayoff = oadd(dayoff, (long) -1);
				if (--wday < 0)
					wday = LDAYSPERWEEK - 1;
				--i;
			}
		if (i < 0 || i >= len_months[isleap(y)][m]) {
			error("no day in month matches rule");
			(void) exit(EXIT_FAILURE);
		}
	}
	if (dayoff < 0 && !tt_signed)
		return min_time;
	t = (time_t) dayoff * SECSPERDAY;
	/*
	** Cheap overflow check.
	*/
	if (t / SECSPERDAY != dayoff)
		return (dayoff > 0) ? max_time : min_time;
	return tadd(t, rp->r_tod);
}

static void
newabbr(string)
const char * const	string;
{
	register int	i;

	i = strlen(string) + 1;
	if (charcnt + i > TZ_MAX_CHARS) {
		error("too many, or too long, time zone abbreviations");
		(void) exit(EXIT_FAILURE);
	}
	(void) strcpy(&chars[charcnt], string);
	charcnt += eitol(i);
}

static int
mkdirs(argname)
char * const	argname;
{
	register char *	name;
	register char *	cp;

	if (argname == NULL || *argname == '\0')
		return 0;
	cp = name = ecpyalloc(argname);
	while ((cp = strchr(cp + 1, '/')) != 0) {
		*cp = '\0';
#ifndef unix
		/*
		** MS-DOS drive specifier?
		*/
		if (strlen(name) == 2 && isascii(name[0]) &&
			isalpha(name[0]) && name[1] == ':') {
				*cp = '/';
				continue;
		}
#endif /* !defined unix */
		if (!itsdir(name)) {
			/*
			** It doesn't seem to exist, so we try to create it.
			*/
			if (emkdir(name, 0755) != 0) {
				(void) fprintf(stderr,
					"%s: Can't create directory ",
					progname);
				(void) perror(name);
				ifree(name);
				return -1;
			}
		}
		*cp = '/';
	}
	ifree(name);
	return 0;
}

static long
eitol(i)
const int	i;
{
	long	l;

	l = i;
	if ((i < 0 && l >= 0) || (i == 0 && l != 0) || (i > 0 && l <= 0)) {
		(void) fprintf(stderr,
			"%s: %d did not sign extend correctly\n",
			progname, i);
		(void) exit(EXIT_FAILURE);
	}
	return l;
}

/*
** UNIX is a registered trademark of AT&T.
*/