xref: /freebsd/usr.sbin/pw/psdate.c (revision 6829dae12bb055451fa467da4589c43bd03b1e64)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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 #ifndef lint
30 static const char rcsid[] =
31   "$FreeBSD$";
32 #endif /* not lint */
33 
34 #include <ctype.h>
35 #include <err.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <xlocale.h>
39 
40 #include "psdate.h"
41 
42 
43 int
44 numerics(char const * str)
45 {
46 
47 	return (str[strspn(str, "0123456789x")] == '\0');
48 }
49 
50 static int
51 aindex(char const * arr[], char const ** str, int len)
52 {
53 	int             l, i;
54 	char            mystr[32];
55 
56 	mystr[len] = '\0';
57 	l = strlen(strncpy(mystr, *str, len));
58 	for (i = 0; i < l; i++)
59 		mystr[i] = (char) tolower((unsigned char)mystr[i]);
60 	for (i = 0; arr[i] && strcmp(mystr, arr[i]) != 0; i++);
61 	if (arr[i] == NULL)
62 		i = -1;
63 	else {			/* Skip past it */
64 		while (**str && isalpha((unsigned char)**str))
65 			++(*str);
66 		/* And any following whitespace */
67 		while (**str && (**str == ',' || isspace((unsigned char)**str)))
68 			++(*str);
69 	}			/* Return index */
70 	return i;
71 }
72 
73 static int
74 weekday(char const ** str)
75 {
76 	static char const *days[] =
77 	{"sun", "mon", "tue", "wed", "thu", "fri", "sat", NULL};
78 
79 	return aindex(days, str, 3);
80 }
81 
82 static void
83 parse_datesub(char const * str, struct tm *t)
84 {
85 	struct tm	 tm;
86 	locale_t	 l;
87 	int		 i;
88 	char		*ret;
89 	const char	*valid_formats[] = {
90 		"%d-%b-%y",
91 		"%d-%b-%Y",
92 		"%d-%m-%y",
93 		"%d-%m-%Y",
94 		"%H:%M %d-%b-%y",
95 		"%H:%M %d-%b-%Y",
96 		"%H:%M %d-%m-%y",
97 		"%H:%M %d-%m-%Y",
98 		"%H:%M:%S %d-%b-%y",
99 		"%H:%M:%S %d-%b-%Y",
100 		"%H:%M:%S %d-%m-%y",
101 		"%H:%M:%S %d-%m-%Y",
102 		"%d-%b-%y %H:%M",
103 		"%d-%b-%Y %H:%M",
104 		"%d-%m-%y %H:%M",
105 		"%d-%m-%Y %H:%M",
106 		"%d-%b-%y %H:%M:%S",
107 		"%d-%b-%Y %H:%M:%S",
108 		"%d-%m-%y %H:%M:%S",
109 		"%d-%m-%Y %H:%M:%S",
110 		"%H:%M\t%d-%b-%y",
111 		"%H:%M\t%d-%b-%Y",
112 		"%H:%M\t%d-%m-%y",
113 		"%H:%M\t%d-%m-%Y",
114 		"%H:%M\t%S %d-%b-%y",
115 		"%H:%M\t%S %d-%b-%Y",
116 		"%H:%M\t%S %d-%m-%y",
117 		"%H:%M\t%S %d-%m-%Y",
118 		"%d-%b-%y\t%H:%M",
119 		"%d-%b-%Y\t%H:%M",
120 		"%d-%m-%y\t%H:%M",
121 		"%d-%m-%Y\t%H:%M",
122 		"%d-%b-%y\t%H:%M:%S",
123 		"%d-%b-%Y\t%H:%M:%S",
124 		"%d-%m-%y\t%H:%M:%S",
125 		"%d-%m-%Y\t%H:%M:%S",
126 		NULL,
127 	};
128 
129 	l = newlocale(LC_ALL_MASK, "C", NULL);
130 
131 	memset(&tm, 0, sizeof(tm));
132 	for (i=0; valid_formats[i] != NULL; i++) {
133 		ret = strptime_l(str, valid_formats[i], &tm, l);
134 		if (ret && *ret == '\0') {
135 			t->tm_mday = tm.tm_mday;
136 			t->tm_mon = tm.tm_mon;
137 			t->tm_year = tm.tm_year;
138 			t->tm_hour = tm.tm_hour;
139 			t->tm_min = tm.tm_min;
140 			t->tm_sec = tm.tm_sec;
141 			freelocale(l);
142 			return;
143 		}
144 	}
145 
146 	freelocale(l);
147 
148 	errx(EXIT_FAILURE, "Invalid date");
149 }
150 
151 
152 /*-
153  * Parse time must be flexible, it handles the following formats:
154  * nnnnnnnnnnn		UNIX timestamp (all numeric), 0 = now
155  * 0xnnnnnnnn		UNIX timestamp in hexadecimal
156  * 0nnnnnnnnn		UNIX timestamp in octal
157  * 0			Given time
158  * +nnnn[smhdwoy]	Given time + nnnn hours, mins, days, weeks, months or years
159  * -nnnn[smhdwoy]	Given time - nnnn hours, mins, days, weeks, months or years
160  * dd[ ./-]mmm[ ./-]yy	Date }
161  * hh:mm:ss		Time } May be combined
162  */
163 
164 time_t
165 parse_date(time_t dt, char const * str)
166 {
167 	char           *p;
168 	int             i;
169 	long            val;
170 	struct tm      *T;
171 
172 	if (dt == 0)
173 		dt = time(NULL);
174 
175 	while (*str && isspace((unsigned char)*str))
176 		++str;
177 
178 	if (numerics(str)) {
179 		dt = strtol(str, &p, 0);
180 	} else if (*str == '+' || *str == '-') {
181 		val = strtol(str, &p, 0);
182 		switch (*p) {
183 		case 'h':
184 		case 'H':	/* hours */
185 			dt += (val * 3600L);
186 			break;
187 		case '\0':
188 		case 'm':
189 		case 'M':	/* minutes */
190 			dt += (val * 60L);
191 			break;
192 		case 's':
193 		case 'S':	/* seconds */
194 			dt += val;
195 			break;
196 		case 'd':
197 		case 'D':	/* days */
198 			dt += (val * 86400L);
199 			break;
200 		case 'w':
201 		case 'W':	/* weeks */
202 			dt += (val * 604800L);
203 			break;
204 		case 'o':
205 		case 'O':	/* months */
206 			T = localtime(&dt);
207 			T->tm_mon += (int) val;
208 			i = T->tm_mday;
209 			goto fixday;
210 		case 'y':
211 		case 'Y':	/* years */
212 			T = localtime(&dt);
213 			T->tm_year += (int) val;
214 			i = T->tm_mday;
215 	fixday:
216 			dt = mktime(T);
217 			T = localtime(&dt);
218 			if (T->tm_mday != i) {
219 				T->tm_mday = 1;
220 				dt = mktime(T);
221 				dt -= (time_t) 86400L;
222 			}
223 		default:	/* unknown */
224 			break;	/* leave untouched */
225 		}
226 	} else {
227 		char           *q, tmp[64];
228 
229 		/*
230 		 * Skip past any weekday prefix
231 		 */
232 		weekday(&str);
233 		strlcpy(tmp, str, sizeof(tmp));
234 		str = tmp;
235 		T = localtime(&dt);
236 
237 		/*
238 		 * See if we can break off any timezone
239 		 */
240 		while ((q = strrchr(tmp, ' ')) != NULL) {
241 			if (strchr("(+-", q[1]) != NULL)
242 				*q = '\0';
243 			else {
244 				int             j = 1;
245 
246 				while (q[j] && isupper((unsigned char)q[j]))
247 					++j;
248 				if (q[j] == '\0')
249 					*q = '\0';
250 				else
251 					break;
252 			}
253 		}
254 
255 		parse_datesub(tmp, T);
256 		dt = mktime(T);
257 	}
258 	return dt;
259 }
260