myvtm/libtoolkit/strptime.c

/*
* 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.
*/
#include "precompile.h"
#include "strptime.h"

#define asizeof(a)      (sizeof (a) / sizeof ((a)[0]))


struct dtconv {
	char    *abbrev_month_names[12];
	char    *month_names[12];
	char    *abbrev_weekday_names[7];
	char    *weekday_names[7];
	char    *time_format;
	char    *sdate_format;
	char    *dtime_format;
	char    *am_string;
	char    *pm_string;
	char    *ldate_format;
};

static const struct dtconv    En_US = {
	{ "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" },
	"%H:%M:%S",
	"%m/%d/%y",
	"%a %b %e %T %Z %Y",
	"AM",
	"PM",
	"%A, %B, %e, %Y"
};

static void lowercase_string(char *buffer) {
	while(*buffer) {
		*buffer = tolower(*buffer);
		buffer++;
	}
}

TOOLKIT_API char    *strptime(char *buf, char *fmt, struct tm *tm) {
	char    c,
		*ptr;
	int     i, j,
		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 0;
			continue;
		}

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

case 'C':
	buf = strptime(buf, En_US.ldate_format, tm);
	if (buf == 0)
		return 0;
	break;

case 'c':
	buf = strptime(buf, "%x %X", tm);
	if (buf == 0)
		return 0;
	break;

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

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

case 'r':
	buf = strptime(buf, "%I:%M:%S %p", tm);
	if (buf == 0)
		return 0;
	break;

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

case 'X':
	buf = strptime(buf, En_US.time_format, tm);
	if (buf == 0)
		return 0;
	break;

case 'x':
	buf = strptime(buf, En_US.sdate_format, tm);
	if (buf == 0)
		return 0;
	break;

case 'j':
	if (!isdigit(*buf))
		return 0;

	for (i = 0; *buf != 0 && isdigit(*buf); buf++) {
		i *= 10;
		i += *buf - '0';
	}
	if (i > 365)
		return 0;

	tm->tm_yday = i;
	break;

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

	if (!isdigit(*buf))
		return 0;

	for (j=0,i = 0; *buf != 0 && isdigit(*buf) && j<2; j++,buf++) {
		i *= 10;
		i += *buf - '0';
	}
	if (i > 59)
		return 0;

	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 0;

	for (j=0,i = 0; *buf != 0 && isdigit(*buf) && j<2; j++,buf++) {
		i *= 10;
		i += *buf - '0';
	}
	if (c == 'H' || c == 'k') {
		if (i > 23)
			return 0;
	} else if (i > 11)
		return 0;

	tm->tm_hour = i;

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

case 'p':
	len = (int) strlen(En_US.am_string);
	lowercase_string( buf );

	if (strncmp(buf, En_US.am_string, len) == 0) {
		if (tm->tm_hour > 12)
			return 0;
		if (tm->tm_hour == 12)
			tm->tm_hour = 0;
		buf += len;
		break;
	}

	len = (int) strlen(En_US.pm_string);

	if (strncmp(buf, En_US.pm_string, len) == 0) {
		if (tm->tm_hour > 12)
			return 0;
		if (tm->tm_hour != 12)
			tm->tm_hour += 12;
		buf += len;
		break;
	}

	return 0;

case 'A':
case 'a':
	for (i = 0; i < asizeof(En_US.weekday_names); i++) {
		len = (int) strlen(En_US.weekday_names[i]);

		lowercase_string( buf );

		if (strncmp(buf,
			En_US.weekday_names[i],
			len) == 0)
			break;

		len = (int) strlen(En_US.abbrev_weekday_names[i]);
		if (strncmp(buf,
			En_US.abbrev_weekday_names[i],
			len) == 0)
			break;
	}
	if (i == asizeof(En_US.weekday_names))
		return 0;

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

case 'd':
case 'e':
	if (!isdigit(*buf))
		return 0;

	for (j=0,i = 0; *buf != 0 && isdigit(*buf) && j<2; j++,buf++) {
		i *= 10;
		i += *buf - '0';
	}
	if (i > 31)
		return 0;

	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 < asizeof(En_US.month_names); i++) {
		len = (int) strlen(En_US.month_names[i]);

		lowercase_string( buf );
		if (strncmp(buf, En_US.month_names[i],len) == 0)
			break;

		len = (int) strlen(En_US.abbrev_month_names[i]);
		if (strncmp(buf,
			En_US.abbrev_month_names[i],
			len) == 0)
			break;
	}
	if (i == asizeof(En_US.month_names))
		return 0;

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

case 'm':
	if (!isdigit(*buf))
		return 0;

	for (j=0,i = 0; *buf != 0 && isdigit(*buf) && j<2; j++,buf++) {
		i *= 10;
		i += *buf - '0';
	}
	if (i < 1 || i > 12)
		return 0;

	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 0;

	for (j=0,i = 0; *buf != 0 && isdigit(*buf) && j<((c=='Y')?4:2); j++,buf++) {
		i *= 10;
		i += *buf - '0';
	}

	if (c == 'Y')
		i -= 1900;
	else if (i < 69) /*c=='y', 00-68 is for 20xx, the rest is for 19xx*/
		i += 100;

	if (i < 0)
		return 0;

	tm->tm_year = i;

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

	return buf;
}