xref: /netbsd/usr.bin/rump_dhcpclient/common.c (revision e8a634ac)
1 /*
2  * dhcpcd - DHCP client daemon
3  * Copyright (c) 2006-2009 Roy Marples <roy@marples.name>
4  * All rights reserved
5 
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 /* Needed define to get at getline for glibc and FreeBSD */
29 #ifndef _GNU_SOURCE
30 #  define _GNU_SOURCE
31 #endif
32 
33 #include <sys/cdefs.h>
34 
35 #ifdef __APPLE__
36 #  include <mach/mach_time.h>
37 #  include <mach/kern_return.h>
38 #endif
39 
40 #include <sys/param.h>
41 #include <sys/time.h>
42 
43 #include <errno.h>
44 #include <fcntl.h>
45 #include <limits.h>
46 #ifdef BSD
47 #  include <paths.h>
48 #endif
49 #include <stdint.h>
50 #include <stdio.h>
51 #include <stdlib.h>
52 #include <string.h>
53 #include <time.h>
54 #include <unistd.h>
55 
56 #include "common.h"
57 
58 #ifndef _PATH_DEVNULL
59 #  define _PATH_DEVNULL "/dev/null"
60 #endif
61 
62 int clock_monotonic;
63 #ifdef DEBUG_MEMORY
64 static char lbuf_set;
65 #endif
66 
67 #ifdef DEBUG_MEMORY
68 static void
free_lbuf(void)69 free_lbuf(void)
70 {
71 	free(lbuf);
72 	lbuf = NULL;
73 }
74 #endif
75 
76 /* Handy function to get the time.
77  * We only care about time advancements, not the actual time itself
78  * Which is why we use CLOCK_MONOTONIC, but it is not available on all
79  * platforms.
80  */
81 #define NO_MONOTONIC "host does not support a monotonic clock - timing can skew"
82 int
get_monotonic(struct timeval * tp)83 get_monotonic(struct timeval *tp)
84 {
85 	static int posix_clock_set = 0;
86 #if defined(_POSIX_MONOTONIC_CLOCK) && defined(CLOCK_MONOTONIC)
87 	struct timespec ts;
88 	static clockid_t posix_clock;
89 
90 	if (!posix_clock_set) {
91 		if (clock_gettime(CLOCK_MONOTONIC, &ts) == 0) {
92 			posix_clock = CLOCK_MONOTONIC;
93 			clock_monotonic = posix_clock_set = 1;
94 		}
95 	}
96 
97 	if (clock_monotonic) {
98 		if (clock_gettime(posix_clock, &ts) == 0) {
99 			tp->tv_sec = ts.tv_sec;
100 			tp->tv_usec = ts.tv_nsec / 1000;
101 			return 0;
102 		}
103 	}
104 #elif defined(__APPLE__)
105 #define NSEC_PER_SEC 1000000000
106 	/* We can use mach kernel functions here.
107 	 * This is crap though - why can't they implement clock_gettime?*/
108 	static struct mach_timebase_info info = { 0, 0 };
109 	static double factor = 0.0;
110 	uint64_t nano;
111 	long rem;
112 
113 	if (!posix_clock_set) {
114 		if (mach_timebase_info(&info) == KERN_SUCCESS) {
115 			factor = (double)info.numer / (double)info.denom;
116 			clock_monotonic = posix_clock_set = 1;
117 		}
118 	}
119 	if (clock_monotonic) {
120 		nano = mach_absolute_time();
121 		if ((info.denom != 1 || info.numer != 1) && factor != 0.0)
122 			nano *= factor;
123 		tp->tv_sec = nano / NSEC_PER_SEC;
124 		rem = nano % NSEC_PER_SEC;
125 		if (rem < 0) {
126 			tp->tv_sec--;
127 			rem += NSEC_PER_SEC;
128 		}
129 		tp->tv_usec = rem / 1000;
130 		return 0;
131 	}
132 #endif
133 
134 	/* Something above failed, so fall back to gettimeofday */
135 	if (!posix_clock_set) {
136 		posix_clock_set = 1;
137 	}
138 	return gettimeofday(tp, NULL);
139 }
140 
141 time_t
uptime(void)142 uptime(void)
143 {
144 	struct timeval tv;
145 
146 	if (get_monotonic(&tv) == -1)
147 		return -1;
148 	return tv.tv_sec;
149 }
150 
151 void *
xmalloc(size_t s)152 xmalloc(size_t s)
153 {
154 	void *value = malloc(s);
155 
156 	if (value != NULL)
157 		return value;
158 	abort();
159 	/* NOTREACHED */
160 }
161 
162 void *
xzalloc(size_t s)163 xzalloc(size_t s)
164 {
165 	void *value = xmalloc(s);
166 
167 	memset(value, 0, s);
168 	return value;
169 }
170 
171 void *
xrealloc(void * ptr,size_t s)172 xrealloc(void *ptr, size_t s)
173 {
174 	void *value = realloc(ptr, s);
175 
176 	if (value != NULL)
177 		return value;
178 	abort();
179 	/* NOTREACHED */
180 }
181 
182 char *
xstrdup(const char * str)183 xstrdup(const char *str)
184 {
185 	char *value;
186 
187 	if (str == NULL)
188 		return NULL;
189 
190 	if ((value = strdup(str)) != NULL)
191 		return value;
192 
193 	abort();
194 	/* NOTREACHED */
195 }
196