1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (C) 1996
5 *	David L. Nugent.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY DAVID L. NUGENT AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL DAVID L. NUGENT OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#include <ctype.h>
30#include <err.h>
31#include <stdlib.h>
32#include <string.h>
33#include <xlocale.h>
34
35#include "psdate.h"
36
37
38int
39numerics(char const * str)
40{
41
42	return (str[strspn(str, "0123456789x")] == '\0');
43}
44
45static int
46aindex(char const * arr[], char const ** str, int len)
47{
48	int             l, i;
49	char            mystr[32];
50
51	mystr[len] = '\0';
52	l = strlen(strncpy(mystr, *str, len));
53	for (i = 0; i < l; i++)
54		mystr[i] = (char) tolower((unsigned char)mystr[i]);
55	for (i = 0; arr[i] && strcmp(mystr, arr[i]) != 0; i++);
56	if (arr[i] == NULL)
57		i = -1;
58	else {			/* Skip past it */
59		while (**str && isalpha((unsigned char)**str))
60			++(*str);
61		/* And any following whitespace */
62		while (**str && (**str == ',' || isspace((unsigned char)**str)))
63			++(*str);
64	}			/* Return index */
65	return i;
66}
67
68static int
69weekday(char const ** str)
70{
71	static char const *days[] =
72	{"sun", "mon", "tue", "wed", "thu", "fri", "sat", NULL};
73
74	return aindex(days, str, 3);
75}
76
77static void
78parse_datesub(char const * str, struct tm *t)
79{
80	struct tm	 tm;
81	locale_t	 l;
82	int		 i;
83	char		*ret;
84	const char	*valid_formats[] = {
85		"%d-%b-%y",
86		"%d-%b-%Y",
87		"%d-%m-%y",
88		"%d-%m-%Y",
89		"%H:%M %d-%b-%y",
90		"%H:%M %d-%b-%Y",
91		"%H:%M %d-%m-%y",
92		"%H:%M %d-%m-%Y",
93		"%H:%M:%S %d-%b-%y",
94		"%H:%M:%S %d-%b-%Y",
95		"%H:%M:%S %d-%m-%y",
96		"%H:%M:%S %d-%m-%Y",
97		"%d-%b-%y %H:%M",
98		"%d-%b-%Y %H:%M",
99		"%d-%m-%y %H:%M",
100		"%d-%m-%Y %H:%M",
101		"%d-%b-%y %H:%M:%S",
102		"%d-%b-%Y %H:%M:%S",
103		"%d-%m-%y %H:%M:%S",
104		"%d-%m-%Y %H:%M:%S",
105		"%H:%M\t%d-%b-%y",
106		"%H:%M\t%d-%b-%Y",
107		"%H:%M\t%d-%m-%y",
108		"%H:%M\t%d-%m-%Y",
109		"%H:%M\t%S %d-%b-%y",
110		"%H:%M\t%S %d-%b-%Y",
111		"%H:%M\t%S %d-%m-%y",
112		"%H:%M\t%S %d-%m-%Y",
113		"%d-%b-%y\t%H:%M",
114		"%d-%b-%Y\t%H:%M",
115		"%d-%m-%y\t%H:%M",
116		"%d-%m-%Y\t%H:%M",
117		"%d-%b-%y\t%H:%M:%S",
118		"%d-%b-%Y\t%H:%M:%S",
119		"%d-%m-%y\t%H:%M:%S",
120		"%d-%m-%Y\t%H:%M:%S",
121		NULL,
122	};
123
124	l = newlocale(LC_ALL_MASK, "C", NULL);
125
126	for (i=0; valid_formats[i] != NULL; i++) {
127		memset(&tm, 0, sizeof(tm));
128		ret = strptime_l(str, valid_formats[i], &tm, l);
129		if (ret && *ret == '\0') {
130			t->tm_mday = tm.tm_mday;
131			t->tm_mon = tm.tm_mon;
132			t->tm_year = tm.tm_year;
133			t->tm_hour = tm.tm_hour;
134			t->tm_min = tm.tm_min;
135			t->tm_sec = tm.tm_sec;
136			freelocale(l);
137			return;
138		}
139	}
140
141	freelocale(l);
142
143	errx(EXIT_FAILURE, "Invalid date");
144}
145
146
147/*-
148 * Parse time must be flexible, it handles the following formats:
149 * nnnnnnnnnnn		UNIX timestamp (all numeric), 0 = now
150 * 0xnnnnnnnn		UNIX timestamp in hexadecimal
151 * 0nnnnnnnnn		UNIX timestamp in octal
152 * 0			Given time
153 * +nnnn[smhdwoy]	Given time + nnnn hours, mins, days, weeks, months or years
154 * -nnnn[smhdwoy]	Given time - nnnn hours, mins, days, weeks, months or years
155 * dd[ ./-]mmm[ ./-]yy	Date }
156 * hh:mm:ss		Time } May be combined
157 */
158
159time_t
160parse_date(time_t dt, char const * str)
161{
162	char           *p;
163	int             i;
164	long            val;
165	struct tm      *T;
166
167	if (dt == 0)
168		dt = time(NULL);
169
170	while (*str && isspace((unsigned char)*str))
171		++str;
172
173	if (numerics(str)) {
174		dt = strtol(str, &p, 0);
175	} else if (*str == '+' || *str == '-') {
176		val = strtol(str, &p, 0);
177		switch (*p) {
178		case 'h':
179		case 'H':	/* hours */
180			dt += (val * 3600L);
181			break;
182		case '\0':
183		case 'm':
184		case 'M':	/* minutes */
185			dt += (val * 60L);
186			break;
187		case 's':
188		case 'S':	/* seconds */
189			dt += val;
190			break;
191		case 'd':
192		case 'D':	/* days */
193			dt += (val * 86400L);
194			break;
195		case 'w':
196		case 'W':	/* weeks */
197			dt += (val * 604800L);
198			break;
199		case 'o':
200		case 'O':	/* months */
201			T = localtime(&dt);
202			T->tm_mon += (int) val;
203			i = T->tm_mday;
204			goto fixday;
205		case 'y':
206		case 'Y':	/* years */
207			T = localtime(&dt);
208			T->tm_year += (int) val;
209			i = T->tm_mday;
210	fixday:
211			dt = mktime(T);
212			T = localtime(&dt);
213			if (T->tm_mday != i) {
214				T->tm_mday = 1;
215				dt = mktime(T);
216				dt -= (time_t) 86400L;
217			}
218		default:	/* unknown */
219			break;	/* leave untouched */
220		}
221	} else {
222		char           *q, tmp[64];
223
224		/*
225		 * Skip past any weekday prefix
226		 */
227		weekday(&str);
228		strlcpy(tmp, str, sizeof(tmp));
229		str = tmp;
230		T = localtime(&dt);
231
232		/*
233		 * See if we can break off any timezone
234		 */
235		while ((q = strrchr(tmp, ' ')) != NULL) {
236			if (strchr("(+-", q[1]) != NULL)
237				*q = '\0';
238			else {
239				int             j = 1;
240
241				while (q[j] && isupper((unsigned char)q[j]))
242					++j;
243				if (q[j] == '\0')
244					*q = '\0';
245				else
246					break;
247			}
248		}
249
250		parse_datesub(tmp, T);
251		dt = mktime(T);
252	}
253	return dt;
254}
255