auto import from //depot/cupcake/@135843

1 files changed, 872 insertions, 0 deletions

diff --git a/libc/tzcode/strftime.c b/libc/tzcode/strftime.c
new file mode 100644
index 0000000..946c91c
--- /dev/null
+++ b/libc/tzcode/strftime.c
@@ -0,0 +1,872 @@
+#ifndef lint
+#ifndef NOID
+static char	elsieid[] = "@(#)strftime.c	8.1";
+/*
+** Based on the UCB version with the ID appearing below.
+** This is ANSIish only when "multibyte character == plain character".
+*/
+#endif /* !defined NOID */
+#endif /* !defined lint */
+
+#include "private.h"
+
+/*
+** Copyright (c) 1989 The Regents of the University of California.
+** All rights reserved.
+**
+** Redistribution and use in source and binary forms are permitted
+** provided that the above copyright notice and this paragraph are
+** duplicated in all such forms and that any documentation,
+** advertising materials, and other materials related to such
+** distribution and use acknowledge that the software was developed
+** by the University of California, Berkeley. The name of the
+** University may not be used to endorse or promote products derived
+** from this software without specific prior written permission.
+** THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+** IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+** WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+*/
+
+#ifndef LIBC_SCCS
+#ifndef lint
+static const char	sccsid[] = "@(#)strftime.c	5.4 (Berkeley) 3/14/89";
+#endif /* !defined lint */
+#endif /* !defined LIBC_SCCS */
+
+#include "tzfile.h"
+#include "fcntl.h"
+#include "locale.h"
+#include <ctype.h>
+
+struct lc_time_T {
+	const char *	mon[MONSPERYEAR];
+	const char *	month[MONSPERYEAR];
+	const char *	wday[DAYSPERWEEK];
+	const char *	weekday[DAYSPERWEEK];
+	const char *	X_fmt;
+	const char *	x_fmt;
+	const char *	c_fmt;
+	const char *	am;
+	const char *	pm;
+	const char *	date_fmt;
+};
+
+#ifdef LOCALE_HOME
+#include "sys/stat.h"
+static struct lc_time_T		localebuf;
+static struct lc_time_T *	_loc P((void));
+#define Locale	_loc()
+#endif /* defined LOCALE_HOME */
+#ifndef LOCALE_HOME
+#define Locale	(&C_time_locale)
+#endif /* !defined LOCALE_HOME */
+
+static const struct lc_time_T	C_time_locale = {
+	{
+		"Jan", "Feb", "Mar", "Apr", "May", "Jun",
+		"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
+	}, {
+		"January", "February", "March", "April", "May", "June",
+		"July", "August", "September", "October", "November", "December"
+	}, {
+		"Sun", "Mon", "Tue", "Wed",
+		"Thu", "Fri", "Sat"
+	}, {
+		"Sunday", "Monday", "Tuesday", "Wednesday",
+		"Thursday", "Friday", "Saturday"
+	},
+
+	/* X_fmt */
+	"%H:%M:%S",
+
+	/*
+	** x_fmt
+	** C99 requires this format.
+	** Using just numbers (as here) makes Quakers happier;
+	** it's also compatible with SVR4.
+	*/
+	"%m/%d/%y",
+
+	/*
+	** c_fmt
+	** C99 requires this format.
+	** Previously this code used "%D %X", but we now conform to C99.
+	** Note that
+	**	"%a %b %d %H:%M:%S %Y"
+	** is used by Solaris 2.3.
+	*/
+	"%a %b %e %T %Y",
+
+	/* am */
+	"AM",
+
+	/* pm */
+	"PM",
+
+	/* date_fmt */
+	"%a %b %e %H:%M:%S %Z %Y"
+};
+
+static char *	_add P((const char *, char *, const char *, int));
+static char *	_conv P((int, const char *, char *, const char *));
+static char *	_fmt P((const char *, const struct tm *, char *, const char *,
+			int *));
+static char *	_yconv P((int, int, int, int, char *, const char *, int));
+static char *	getformat P((int, char *, char *, char *, char *));
+
+extern char *	tzname[];
+
+#ifndef YEAR_2000_NAME
+#define YEAR_2000_NAME	"CHECK_STRFTIME_FORMATS_FOR_TWO_DIGIT_YEARS"
+#endif /* !defined YEAR_2000_NAME */
+
+#define IN_NONE	0
+#define IN_SOME	1
+#define IN_THIS	2
+#define IN_ALL	3
+
+#define FORCE_LOWER_CASE 0x100
+
+size_t
+strftime(s, maxsize, format, t)
+char * const		s;
+const size_t		maxsize;
+const char * const	format;
+const struct tm * const	t;
+{
+	char *	p;
+	int	warn;
+
+	tzset();
+#ifdef LOCALE_HOME
+	localebuf.mon[0] = 0;
+#endif /* defined LOCALE_HOME */
+	warn = IN_NONE;
+	p = _fmt(((format == NULL) ? "%c" : format), t, s, s + maxsize, &warn);
+#ifndef NO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU
+	if (warn != IN_NONE && getenv(YEAR_2000_NAME) != NULL) {
+		(void) fprintf(stderr, "\n");
+		if (format == NULL)
+			(void) fprintf(stderr, "NULL strftime format ");
+		else	(void) fprintf(stderr, "strftime format \"%s\" ",
+				format);
+		(void) fprintf(stderr, "yields only two digits of years in ");
+		if (warn == IN_SOME)
+			(void) fprintf(stderr, "some locales");
+		else if (warn == IN_THIS)
+			(void) fprintf(stderr, "the current locale");
+		else	(void) fprintf(stderr, "all locales");
+		(void) fprintf(stderr, "\n");
+	}
+#endif /* !defined NO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU */
+	if (p == s + maxsize)
+		return 0;
+	*p = '\0';
+	return p - s;
+}
+
+static char *getformat(int modifier, char *normal, char *underscore,
+                       char *dash, char *zero) {
+    switch (modifier) {
+    case '_':
+        return underscore;
+
+    case '-':
+        return dash;
+
+    case '0':
+        return zero;
+    }
+
+    return normal;
+}
+
+static char *
+_fmt(format, t, pt, ptlim, warnp)
+const char *		format;
+const struct tm * const	t;
+char *			pt;
+const char * const	ptlim;
+int *			warnp;
+{
+	for ( ; *format; ++format) {
+		if (*format == '%') {
+            int modifier = 0;
+label:
+			switch (*++format) {
+			case '\0':
+				--format;
+				break;
+			case 'A':
+				pt = _add((t->tm_wday < 0 ||
+					t->tm_wday >= DAYSPERWEEK) ?
+					"?" : Locale->weekday[t->tm_wday],
+					pt, ptlim, modifier);
+				continue;
+			case 'a':
+				pt = _add((t->tm_wday < 0 ||
+					t->tm_wday >= DAYSPERWEEK) ?
+					"?" : Locale->wday[t->tm_wday],
+					pt, ptlim, modifier);
+				continue;
+			case 'B':
+				pt = _add((t->tm_mon < 0 ||
+					t->tm_mon >= MONSPERYEAR) ?
+					"?" : Locale->month[t->tm_mon],
+					pt, ptlim, modifier);
+				continue;
+			case 'b':
+			case 'h':
+				pt = _add((t->tm_mon < 0 ||
+					t->tm_mon >= MONSPERYEAR) ?
+					"?" : Locale->mon[t->tm_mon],
+					pt, ptlim, modifier);
+				continue;
+			case 'C':
+				/*
+				** %C used to do a...
+				**	_fmt("%a %b %e %X %Y", t);
+				** ...whereas now POSIX 1003.2 calls for
+				** something completely different.
+				** (ado, 1993-05-24)
+				*/
+				pt = _yconv(t->tm_year, TM_YEAR_BASE, 1, 0,
+					pt, ptlim, modifier);
+				continue;
+			case 'c':
+				{
+				int warn2 = IN_SOME;
+
+				pt = _fmt(Locale->c_fmt, t, pt, ptlim, warnp);
+				if (warn2 == IN_ALL)
+					warn2 = IN_THIS;
+				if (warn2 > *warnp)
+					*warnp = warn2;
+				}
+				continue;
+			case 'D':
+                                pt = _fmt("%m/%d/%y", t, pt, ptlim, warnp);
+				continue;
+			case 'd':
+                                pt = _conv(t->tm_mday,
+                                           getformat(modifier, "%02d",
+                                                     "%2d", "%d", "%02d"),
+                                           pt, ptlim);
+				continue;
+			case 'E':
+			case 'O':
+				/*
+				** C99 locale modifiers.
+				** The sequences
+				**	%Ec %EC %Ex %EX %Ey %EY
+				**	%Od %oe %OH %OI %Om %OM
+				**	%OS %Ou %OU %OV %Ow %OW %Oy
+				** are supposed to provide alternate
+				** representations.
+				*/
+				goto label;
+            case '_':
+            case '-':
+            case '0':
+            case '^':
+            case '#':
+                modifier = *format;
+                goto label;
+			case 'e':
+				pt = _conv(t->tm_mday,
+                                           getformat(modifier, "%2d",
+                                                     "%2d", "%d", "%02d"),
+                                           pt, ptlim);
+				continue;
+			case 'F':
+				pt = _fmt("%Y-%m-%d", t, pt, ptlim, warnp);
+				continue;
+			case 'H':
+				pt = _conv(t->tm_hour,
+                                           getformat(modifier, "%02d",
+                                                     "%2d", "%d", "%02d"),
+                                           pt, ptlim);
+				continue;
+			case 'I':
+				pt = _conv((t->tm_hour % 12) ?
+					(t->tm_hour % 12) : 12,
+					getformat(modifier, "%02d",
+                                                  "%2d", "%d", "%02d"),
+                                        pt, ptlim);
+				continue;
+			case 'j':
+				pt = _conv(t->tm_yday + 1,
+                           getformat(modifier, "%03d", "%3d", "%d", "%03d"),
+                           pt, ptlim);
+				continue;
+			case 'k':
+				/*
+				** This used to be...
+				**	_conv(t->tm_hour % 12 ?
+				**		t->tm_hour % 12 : 12, 2, ' ');
+				** ...and has been changed to the below to
+				** match SunOS 4.1.1 and Arnold Robbins'
+				** strftime version 3.0. That is, "%k" and
+				** "%l" have been swapped.
+				** (ado, 1993-05-24)
+				*/
+				pt = _conv(t->tm_hour,
+                                           getformat(modifier, "%2d",
+                                                     "%2d", "%d", "%02d"),
+                                           pt, ptlim);
+				continue;
+#ifdef KITCHEN_SINK
+			case 'K':
+				/*
+				** After all this time, still unclaimed!
+				*/
+				pt = _add("kitchen sink", pt, ptlim, modifier);
+				continue;
+#endif /* defined KITCHEN_SINK */
+			case 'l':
+				/*
+				** This used to be...
+				**	_conv(t->tm_hour, 2, ' ');
+				** ...and has been changed to the below to
+				** match SunOS 4.1.1 and Arnold Robbin's
+				** strftime version 3.0. That is, "%k" and
+				** "%l" have been swapped.
+				** (ado, 1993-05-24)
+				*/
+				pt = _conv((t->tm_hour % 12) ?
+					(t->tm_hour % 12) : 12,
+					getformat(modifier, "%2d",
+                                                  "%2d", "%d", "%02d"),
+                                        pt, ptlim);
+				continue;
+			case 'M':
+				pt = _conv(t->tm_min,
+                                           getformat(modifier, "%02d",
+                                                     "%2d", "%d", "%02d"),
+                                           pt, ptlim);
+				continue;
+			case 'm':
+				pt = _conv(t->tm_mon + 1,
+                                           getformat(modifier, "%02d",
+                                                     "%2d", "%d", "%02d"),
+                                           pt, ptlim);
+				continue;
+			case 'n':
+				pt = _add("\n", pt, ptlim, modifier);
+				continue;
+			case 'p':
+				pt = _add((t->tm_hour >= (HOURSPERDAY / 2)) ?
+					Locale->pm :
+					Locale->am,
+					pt, ptlim, modifier);
+				continue;
+			case 'P':
+				pt = _add((t->tm_hour >= (HOURSPERDAY / 2)) ?
+					Locale->pm :
+					Locale->am,
+					pt, ptlim, FORCE_LOWER_CASE);
+				continue;
+			case 'R':
+				pt = _fmt("%H:%M", t, pt, ptlim, warnp);
+				continue;
+			case 'r':
+				pt = _fmt("%I:%M:%S %p", t, pt, ptlim, warnp);
+				continue;
+			case 'S':
+				pt = _conv(t->tm_sec,
+                                           getformat(modifier, "%02d",
+                                                     "%2d", "%d", "%02d"),
+                                           pt, ptlim);
+				continue;
+			case 's':
+				{
+					struct tm	tm;
+					char		buf[INT_STRLEN_MAXIMUM(
+								time_t) + 1];
+					time_t		mkt;
+
+					tm = *t;
+					mkt = mktime(&tm);
+					if (TYPE_SIGNED(time_t))
+						(void) sprintf(buf, "%ld",
+							(long) mkt);
+					else	(void) sprintf(buf, "%lu",
+							(unsigned long) mkt);
+					pt = _add(buf, pt, ptlim, modifier);
+				}
+				continue;
+			case 'T':
+				pt = _fmt("%H:%M:%S", t, pt, ptlim, warnp);
+				continue;
+			case 't':
+				pt = _add("\t", pt, ptlim, modifier);
+				continue;
+			case 'U':
+				pt = _conv((t->tm_yday + DAYSPERWEEK -
+					t->tm_wday) / DAYSPERWEEK,
+					getformat(modifier, "%02d",
+                                                  "%2d", "%d", "%02d"),
+                                        pt, ptlim);
+				continue;
+			case 'u':
+				/*
+				** From Arnold Robbins' strftime version 3.0:
+				** "ISO 8601: Weekday as a decimal number
+				** [1 (Monday) - 7]"
+				** (ado, 1993-05-24)
+				*/
+				pt = _conv((t->tm_wday == 0) ?
+					DAYSPERWEEK : t->tm_wday, "%d", pt, ptlim);
+				continue;
+			case 'V':	/* ISO 8601 week number */
+			case 'G':	/* ISO 8601 year (four digits) */
+			case 'g':	/* ISO 8601 year (two digits) */
+/*
+** From Arnold Robbins' strftime version 3.0: "the week number of the
+** year (the first Monday as the first day of week 1) as a decimal number
+** (01-53)."
+** (ado, 1993-05-24)
+**
+** From "http://www.ft.uni-erlangen.de/~mskuhn/iso-time.html" by Markus Kuhn:
+** "Week 01 of a year is per definition the first week which has the
+** Thursday in this year, which is equivalent to the week which contains
+** the fourth day of January. In other words, the first week of a new year
+** is the week which has the majority of its days in the new year. Week 01
+** might also contain days from the previous year and the week before week
+** 01 of a year is the last week (52 or 53) of the previous year even if
+** it contains days from the new year. A week starts with Monday (day 1)
+** and ends with Sunday (day 7). For example, the first week of the year
+** 1997 lasts from 1996-12-30 to 1997-01-05..."
+** (ado, 1996-01-02)
+*/
+				{
+					int	year;
+					int	base;
+					int	yday;
+					int	wday;
+					int	w;
+
+					year = t->tm_year;
+					base = TM_YEAR_BASE;
+					yday = t->tm_yday;
+					wday = t->tm_wday;
+					for ( ; ; ) {
+						int	len;
+						int	bot;
+						int	top;
+
+						len = isleap_sum(year, base) ?
+							DAYSPERLYEAR :
+							DAYSPERNYEAR;
+						/*
+						** What yday (-3 ... 3) does
+						** the ISO year begin on?
+						*/
+						bot = ((yday + 11 - wday) %
+							DAYSPERWEEK) - 3;
+						/*
+						** What yday does the NEXT
+						** ISO year begin on?
+						*/
+						top = bot -
+							(len % DAYSPERWEEK);
+						if (top < -3)
+							top += DAYSPERWEEK;
+						top += len;
+						if (yday >= top) {
+							++base;
+							w = 1;
+							break;
+						}
+						if (yday >= bot) {
+							w = 1 + ((yday - bot) /
+								DAYSPERWEEK);
+							break;
+						}
+						--base;
+						yday += isleap_sum(year, base) ?
+							DAYSPERLYEAR :
+							DAYSPERNYEAR;
+					}
+#ifdef XPG4_1994_04_09
+					if ((w == 52 &&
+						t->tm_mon == TM_JANUARY) ||
+						(w == 1 &&
+						t->tm_mon == TM_DECEMBER))
+							w = 53;
+#endif /* defined XPG4_1994_04_09 */
+					if (*format == 'V')
+						pt = _conv(w,
+                                                           getformat(modifier,
+                                                                     "%02d",
+                                                                     "%2d",
+                                                                     "%d",
+                                                                     "%02d"),
+							   pt, ptlim);
+					else if (*format == 'g') {
+						*warnp = IN_ALL;
+						pt = _yconv(year, base, 0, 1,
+							pt, ptlim, modifier);
+					} else	pt = _yconv(year, base, 1, 1,
+							pt, ptlim, modifier);
+				}
+				continue;
+			case 'v':
+				/*
+				** From Arnold Robbins' strftime version 3.0:
+				** "date as dd-bbb-YYYY"
+				** (ado, 1993-05-24)
+				*/
+				pt = _fmt("%e-%b-%Y", t, pt, ptlim, warnp);
+				continue;
+			case 'W':
+				pt = _conv((t->tm_yday + DAYSPERWEEK -
+					(t->tm_wday ?
+					(t->tm_wday - 1) :
+					(DAYSPERWEEK - 1))) / DAYSPERWEEK,
+					getformat(modifier, "%02d",
+                                                  "%2d", "%d", "%02d"),
+                                        pt, ptlim);
+				continue;
+			case 'w':
+				pt = _conv(t->tm_wday, "%d", pt, ptlim);
+				continue;
+			case 'X':
+				pt = _fmt(Locale->X_fmt, t, pt, ptlim, warnp);
+				continue;
+			case 'x':
+				{
+				int	warn2 = IN_SOME;
+
+				pt = _fmt(Locale->x_fmt, t, pt, ptlim, &warn2);
+				if (warn2 == IN_ALL)
+					warn2 = IN_THIS;
+				if (warn2 > *warnp)
+					*warnp = warn2;
+				}
+				continue;
+			case 'y':
+				*warnp = IN_ALL;
+				pt = _yconv(t->tm_year, TM_YEAR_BASE, 0, 1,
+					pt, ptlim, modifier);
+				continue;
+			case 'Y':
+				pt = _yconv(t->tm_year, TM_YEAR_BASE, 1, 1,
+					pt, ptlim, modifier);
+				continue;
+			case 'Z':
+#ifdef TM_ZONE
+				if (t->TM_ZONE != NULL)
+					pt = _add(t->TM_ZONE, pt, ptlim,
+                                                  modifier);
+				else
+#endif /* defined TM_ZONE */
+				if (t->tm_isdst >= 0)
+					pt = _add(tzname[t->tm_isdst != 0],
+						pt, ptlim, modifier);
+				/*
+				** C99 says that %Z must be replaced by the
+				** empty string if the time zone is not
+				** determinable.
+				*/
+				continue;
+			case 'z':
+				{
+				int		diff;
+				char const *	sign;
+
+				if (t->tm_isdst < 0)
+					continue;
+#ifdef TM_GMTOFF
+				diff = t->TM_GMTOFF;
+#else /* !defined TM_GMTOFF */
+				/*
+				** C99 says that the UTC offset must
+				** be computed by looking only at
+				** tm_isdst. This requirement is
+				** incorrect, since it means the code
+				** must rely on magic (in this case
+				** altzone and timezone), and the
+				** magic might not have the correct
+				** offset. Doing things correctly is
+				** tricky and requires disobeying C99;
+				** see GNU C strftime for details.
+				** For now, punt and conform to the
+				** standard, even though it's incorrect.
+				**
+				** C99 says that %z must be replaced by the
+				** empty string if the time zone is not
+				** determinable, so output nothing if the
+				** appropriate variables are not available.
+				*/
+				if (t->tm_isdst == 0)
+#ifdef USG_COMPAT
+					diff = -timezone;
+#else /* !defined USG_COMPAT */
+					continue;
+#endif /* !defined USG_COMPAT */
+				else
+#ifdef ALTZONE
+					diff = -altzone;
+#else /* !defined ALTZONE */
+					continue;
+#endif /* !defined ALTZONE */
+#endif /* !defined TM_GMTOFF */
+				if (diff < 0) {
+					sign = "-";
+					diff = -diff;
+				} else	sign = "+";
+				pt = _add(sign, pt, ptlim, modifier);
+				diff /= SECSPERMIN;
+				diff = (diff / MINSPERHOUR) * 100 +
+					(diff % MINSPERHOUR);
+				pt = _conv(diff,
+                                           getformat(modifier, "%04d",
+                                                     "%4d", "%d", "%04d"),
+                                           pt, ptlim);
+				}
+				continue;
+			case '+':
+				pt = _fmt(Locale->date_fmt, t, pt, ptlim,
+					warnp);
+				continue;
+			case '%':
+			/*
+			** X311J/88-090 (4.12.3.5): if conversion char is
+			** undefined, behavior is undefined. Print out the
+			** character itself as printf(3) also does.
+			*/
+			default:
+				break;
+			}
+		}
+		if (pt == ptlim)
+			break;
+		*pt++ = *format;
+	}
+	return pt;
+}
+
+static char *
+_conv(n, format, pt, ptlim)
+const int		n;
+const char * const	format;
+char * const		pt;
+const char * const	ptlim;
+{
+	char	buf[INT_STRLEN_MAXIMUM(int) + 1];
+
+	(void) sprintf(buf, format, n);
+	return _add(buf, pt, ptlim, 0);
+}
+
+static char *
+_add(str, pt, ptlim, modifier)
+const char *		str;
+char *			pt;
+const char * const	ptlim;
+int                     modifier;
+{
+        int c;
+
+        switch (modifier) {
+        case FORCE_LOWER_CASE:
+                while (pt < ptlim && (*pt = tolower(*str++)) != '\0') {
+                        ++pt;
+                }
+                break;
+
+        case '^':
+                while (pt < ptlim && (*pt = toupper(*str++)) != '\0') {
+                        ++pt;
+                }
+                break;
+
+        case '#':
+                while (pt < ptlim && (c = *str++) != '\0') {
+                        if (isupper(c)) {
+                                c = tolower(c);
+                        } else if (islower(c)) {
+                                c = toupper(c);
+                        }
+                        *pt = c;
+                        ++pt;
+                }
+
+                break;
+
+        default:
+                while (pt < ptlim && (*pt = *str++) != '\0') {
+                        ++pt;
+                }
+        }
+
+	return pt;
+}
+
+/*
+** POSIX and the C Standard are unclear or inconsistent about
+** what %C and %y do if the year is negative or exceeds 9999.
+** Use the convention that %C concatenated with %y yields the
+** same output as %Y, and that %Y contains at least 4 bytes,
+** with more only if necessary.
+*/
+
+static char *
+_yconv(a, b, convert_top, convert_yy, pt, ptlim, modifier)
+const int		a;
+const int		b;
+const int		convert_top;
+const int		convert_yy;
+char *			pt;
+const char * const	ptlim;
+int                     modifier;
+{
+	register int	lead;
+	register int	trail;
+
+#define DIVISOR	100
+	trail = a % DIVISOR + b % DIVISOR;
+	lead = a / DIVISOR + b / DIVISOR + trail / DIVISOR;
+	trail %= DIVISOR;
+	if (trail < 0 && lead > 0) {
+		trail += DIVISOR;
+		--lead;
+	} else if (lead < 0 && trail > 0) {
+		trail -= DIVISOR;
+		++lead;
+	}
+	if (convert_top) {
+		if (lead == 0 && trail < 0)
+			pt = _add("-0", pt, ptlim, modifier);
+		else	pt = _conv(lead, getformat(modifier, "%02d",
+                                                   "%2d", "%d", "%02d"),
+                                   pt, ptlim);
+	}
+	if (convert_yy)
+		pt = _conv(((trail < 0) ? -trail : trail),
+                           getformat(modifier, "%02d", "%2d", "%d", "%02d"),
+                           pt, ptlim);
+	return pt;
+}
+
+#ifdef LOCALE_HOME
+static struct lc_time_T *
+_loc P((void))
+{
+	static const char	locale_home[] = LOCALE_HOME;
+	static const char	lc_time[] = "LC_TIME";
+	static char *		locale_buf;
+
+	int			fd;
+	int			oldsun;	/* "...ain't got nothin' to do..." */
+	char *			lbuf;
+	char *			name;
+	char *			p;
+	const char **		ap;
+	const char *		plim;
+	char			filename[FILENAME_MAX];
+	struct stat		st;
+	size_t			namesize;
+	size_t			bufsize;
+
+	/*
+	** Use localebuf.mon[0] to signal whether locale is already set up.
+	*/
+	if (localebuf.mon[0])
+		return &localebuf;
+	name = setlocale(LC_TIME, (char *) NULL);
+	if (name == NULL || *name == '\0')
+		goto no_locale;
+	/*
+	** If the locale name is the same as our cache, use the cache.
+	*/
+	lbuf = locale_buf;
+	if (lbuf != NULL && strcmp(name, lbuf) == 0) {
+		p = lbuf;
+		for (ap = (const char **) &localebuf;
+			ap < (const char **) (&localebuf + 1);
+				++ap)
+					*ap = p += strlen(p) + 1;
+		return &localebuf;
+	}
+	/*
+	** Slurp the locale file into the cache.
+	*/
+	namesize = strlen(name) + 1;
+	if (sizeof filename <
+		((sizeof locale_home) + namesize + (sizeof lc_time)))
+			goto no_locale;
+	oldsun = 0;
+	(void) sprintf(filename, "%s/%s/%s", locale_home, name, lc_time);
+	fd = open(filename, O_RDONLY);
+	if (fd < 0) {
+		/*
+		** Old Sun systems have a different naming and data convention.
+		*/
+		oldsun = 1;
+		(void) sprintf(filename, "%s/%s/%s", locale_home,
+			lc_time, name);
+		fd = open(filename, O_RDONLY);
+		if (fd < 0)
+			goto no_locale;
+	}
+	if (fstat(fd, &st) != 0)
+		goto bad_locale;
+	if (st.st_size <= 0)
+		goto bad_locale;
+	bufsize = namesize + st.st_size;
+	locale_buf = NULL;
+	lbuf = (lbuf == NULL) ? malloc(bufsize) : realloc(lbuf, bufsize);
+	if (lbuf == NULL)
+		goto bad_locale;
+	(void) strcpy(lbuf, name);
+	p = lbuf + namesize;
+	plim = p + st.st_size;
+	if (read(fd, p, (size_t) st.st_size) != st.st_size)
+		goto bad_lbuf;
+	if (close(fd) != 0)
+		goto bad_lbuf;
+	/*
+	** Parse the locale file into localebuf.
+	*/
+	if (plim[-1] != '\n')
+		goto bad_lbuf;
+	for (ap = (const char **) &localebuf;
+		ap < (const char **) (&localebuf + 1);
+			++ap) {
+				if (p == plim)
+					goto bad_lbuf;
+				*ap = p;
+				while (*p != '\n')
+					++p;
+				*p++ = '\0';
+	}
+	if (oldsun) {
+		/*
+		** SunOS 4 used an obsolescent format; see localdtconv(3).
+		** c_fmt had the ``short format for dates and times together''
+		** (SunOS 4 date, "%a %b %e %T %Z %Y" in the C locale);
+		** date_fmt had the ``long format for dates''
+		** (SunOS 4 strftime %C, "%A, %B %e, %Y" in the C locale).
+		** Discard the latter in favor of the former.
+		*/
+		localebuf.date_fmt = localebuf.c_fmt;
+	}
+	/*
+	** Record the successful parse in the cache.
+	*/
+	locale_buf = lbuf;
+
+	return &localebuf;
+
+bad_lbuf:
+	free(lbuf);
+bad_locale:
+	(void) close(fd);
+no_locale:
+	localebuf = C_time_locale;
+	locale_buf = NULL;
+	return &localebuf;
+}
+#endif /* defined LOCALE_HOME */