xref: /src/lib/libc/time/strptime.c

/*	$NetBSD: strptime.c,v 1.2 1997/05/06 13:06:48 kleink Exp $	*/

/*
 * Copyright (c) 1994 Powerdog Industries.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer
 *    in the documentation and/or other materials provided with the
 *    distribution.
 * 3. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgement:
 *      This product includes software developed by Powerdog Industries.
 * 4. The name of Powerdog Industries may not be used to endorse or
 *    promote products derived from this software without specific prior
 *    written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY POWERDOG INDUSTRIES ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE POWERDOG INDUSTRIES BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef lint
#if 0
static char copyright[] =
"@(#) Copyright (c) 1994 Powerdog Industries.  All rights reserved.";
static char sccsid[] = "@(#)strptime.c  0.1 (Powerdog) 94/03/27";
#else
static char rcsid[] = "$NetBSD: strptime.c,v 1.2 1997/05/06 13:06:48 kleink Exp $";
#endif
#endif /* not lint */

#include <sys/localedef.h>
#include <locale.h>
#include <time.h>
#include <ctype.h>
#include <string.h>

char *
strptime(buf, fmt, tm)
	const char *buf, *fmt;
	struct tm *tm;
{
	const char *ptr;
        char c;
	int i, len;

	ptr = fmt;
	while (*ptr != 0) {
		if (*buf == 0)
			break;

		c = *ptr++;

		if (c != '%') {
			if (isspace(c))
				while (*buf != 0 && isspace(*buf))
					buf++;
			else if (c != *buf++)
				return (NULL);
			continue;
		}

		c = *ptr++;
		switch (c) {
		case 0:
		case '%':
			if (*buf++ != '%')
				return (NULL);
			break;

		case 'c':
			buf = strptime(buf, _CurrentTimeLocale->d_t_fmt, tm);
			if (buf == 0)
				return (NULL);
			break;

		case 'D':
			buf = strptime(buf, "%m/%d/%y", tm);
			if (buf == 0)
				return (NULL);
			break;

		case 'R':
			buf = strptime(buf, "%H:%M", tm);
			if (buf == 0)
				return (NULL);
			break;

		case 'r':
			buf = strptime(buf, _CurrentTimeLocale->t_fmt_ampm,tm);
			if (buf == 0)
				return (NULL);
			break;

		case 'T':
			buf = strptime(buf, "%H:%M:%S", tm);
			if (buf == 0)
				return (NULL);
			break;

		case 'X':
			buf = strptime(buf, _CurrentTimeLocale->t_fmt, tm);
			if (buf == 0)
				return (NULL);
			break;

		case 'x':
			buf = strptime(buf, _CurrentTimeLocale->d_fmt, tm);
			if (buf == 0)
				return (NULL);
			break;

		case 'j':
			if (!isdigit(*buf))
				return (NULL);

			for (i = 0; *buf != 0 && isdigit(*buf); buf++) {
				i *= 10;
				i += *buf - '0';
			}
			if (i > 366)
				return (NULL);

			tm->tm_yday = i;
			break;

		case 'M':
		case 'S':
			if (*buf == 0 || isspace(*buf))
				break;

			if (!isdigit(*buf))
				return (NULL);

			for (i = 0; *buf != 0 && isdigit(*buf); buf++) {
				i *= 10;
				i += *buf - '0';
			}
			if (i > 59)
				return (NULL);

			if (c == 'M')
				tm->tm_min = i;
			else
				tm->tm_sec = i;

			if (*buf != 0 && isspace(*buf))
				while (*ptr != 0 && !isspace(*ptr))
					ptr++;
			break;

		case 'H':
		case 'I':
		case 'k':
		case 'l':
			if (!isdigit(*buf))
				return (NULL);

			for (i = 0; *buf != 0 && isdigit(*buf); buf++) {
				i *= 10;
				i += *buf - '0';
			}
			if (c == 'H' || c == 'k') {
				if (i > 23)
					return (NULL);
			} else if (i > 11)
				return (NULL);

			tm->tm_hour = i;

			if (*buf != 0 && isspace(*buf))
			while (*ptr != 0 && !isspace(*ptr))
				ptr++;
			break;

		case 'p':
			len = strlen(_CurrentTimeLocale->am_pm[0]);
			if (strncasecmp(buf, _CurrentTimeLocale->am_pm[0],
			                len) == 0) {
				if (tm->tm_hour > 12)
					return (NULL);
				if (tm->tm_hour == 12)
					tm->tm_hour = 0;
				buf += len;
				break;
			}

			len = strlen(_CurrentTimeLocale->am_pm[1]);
			if (strncasecmp(buf, _CurrentTimeLocale->am_pm[1],
			                len) == 0) {
				if (tm->tm_hour > 12)
					return (NULL);
				if (tm->tm_hour != 12)
					tm->tm_hour += 12;
				buf += len;
				break;
			}

                        return (NULL);

		case 'A':
		case 'a':
			for (i = 0; i < 7; i++) {
				len = strlen(_CurrentTimeLocale->day[i]);
				if (strncasecmp(buf,
				                _CurrentTimeLocale->day[i],
				                len) == 0)
					break;

				len = strlen(_CurrentTimeLocale->abday[i]);
				if (strncasecmp(buf,
				                _CurrentTimeLocale->abday[i],
				                len) == 0)
					break;
			}
			if (i == 7)
				return (NULL);

			tm->tm_wday = i;
			buf += len;
			break;

		case 'd':
		case 'e':
			if (!isdigit(*buf))
				return (NULL);

			for (i = 0; *buf != 0 && isdigit(*buf); buf++) {
				i *= 10;
				i += *buf - '0';
			}
			if (i > 31)
				return (NULL);

			tm->tm_mday = i;

			if (*buf != 0 && isspace(*buf))
				while (*ptr != 0 && !isspace(*ptr))
					ptr++;
			break;

		case 'B':
		case 'b':
		case 'h':
			for (i = 0; i < 12; i++) {
				len = strlen(_CurrentTimeLocale->mon[i]);
				if (strncasecmp(buf,
				                _CurrentTimeLocale->mon[i],
				                len) == 0)
					break;

				len = strlen(_CurrentTimeLocale->abmon[i]);
				if (strncasecmp(buf,
				                _CurrentTimeLocale->abmon[i],
				                len) == 0)
					break;
			}
			if (i == 12)
				return (NULL);

			tm->tm_mon = i;
			buf += len;
			break;

		case 'm':
			if (!isdigit(*buf))
				return (NULL);

			for (i = 0; *buf != 0 && isdigit(*buf); buf++) {
				i *= 10;
				i += *buf - '0';
			}
			if (i < 1 || i > 12)
				return (NULL);

			tm->tm_mon = i - 1;

			if (*buf != 0 && isspace(*buf))
				while (*ptr != 0 && !isspace(*ptr))
					ptr++;
			break;

		case 'Y':
		case 'y':
			if (*buf == 0 || isspace(*buf))
				break;

			if (!isdigit(*buf))
				return (NULL);

			for (i = 0; *buf != 0 && isdigit(*buf); buf++) {
				i *= 10;
				i += *buf - '0';
			}
			if (c == 'Y')
				i -= 1900;
			if (i < 0)
				return (NULL);

			tm->tm_year = i;

			if (*buf != 0 && isspace(*buf))
				while (*ptr != 0 && !isspace(*ptr))
					ptr++;
			break;
		}
	}

	return ((char *)buf);
}