aboutsummaryrefslogtreecommitdiff
path: root/networking/udhcp/common.c
blob: 589214bceab99a6909f95b4926819e2aa7e4450e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
/* vi: set sw=4 ts=4: */
/* common.c
 *
 * Functions for debugging and logging as well as some other
 * simple helper functions.
 *
 * Russ Dill <Russ.Dill@asu.edu> 2001-2003
 * Rewritten by Vladimir Oleynik <dzo@simtreas.ru> (C) 2003
 *
 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
 */

#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include <signal.h>
#include <paths.h>
#include <sys/socket.h>
#include <stdarg.h>

#include "common.h"
#include "pidfile.h"


static int daemonized;

long uptime(void)
{
	struct sysinfo info;
	sysinfo(&info);
	return info.uptime;
}


/*
 * This function makes sure our first socket calls
 * aren't going to fd 1 (printf badness...) and are
 * not later closed by daemon()
 */
static inline void sanitize_fds(void)
{
	int zero;
	if ((zero = open(bb_dev_null, O_RDWR, 0)) < 0)
		return;
	while (zero < 3)
		zero = dup(zero);
	close(zero);
}


void background(const char *pidfile)
{
#ifdef __uClinux__
	LOG(LOG_ERR, "Cannot background in uclinux (yet)");
#else /* __uClinux__ */
	int pid_fd;

	/* hold lock during fork. */
	pid_fd = pidfile_acquire(pidfile);
	if (daemon(0, 0) == -1) { /* bb_xdaemon? */
		perror("fork");
		exit(1);
	}
	daemonized++;
	pidfile_write_release(pid_fd);
#endif /* __uClinux__ */
}


#ifdef UDHCP_SYSLOG

void udhcp_logging(int level, const char *fmt, ...)
{
	va_list p;
	va_list p2;

	va_start(p, fmt);
	__va_copy(p2, p);
	if (!daemonized) {
		vprintf(fmt, p);
		putchar('\n');
	}
	vsyslog(level, fmt, p2);
	va_end(p);
}

#else


static char *syslog_level_msg[] = {
	[LOG_EMERG]   = "EMERGENCY!",
	[LOG_ALERT]   = "ALERT!",
	[LOG_CRIT]    = "critical!",
	[LOG_WARNING] = "warning",
	[LOG_ERR]     = "error",
	[LOG_INFO]    = "info",
	[LOG_DEBUG]   = "debug"
};


void udhcp_logging(int level, const char *fmt, ...)
{
	va_list p;

	va_start(p, fmt);
	if (!daemonized) {
		printf("%s, ", syslog_level_msg[level]);
		vprintf(fmt, p);
		putchar('\n');
	}
	va_end(p);
}
#endif


void start_log_and_pid(const char *client_server, const char *pidfile)
{
	int pid_fd;

	/* Make sure our syslog fd isn't overwritten */
	sanitize_fds();

	/* do some other misc startup stuff while we are here to save bytes */
	pid_fd = pidfile_acquire(pidfile);
	pidfile_write_release(pid_fd);

	/* equivelent of doing a fflush after every \n */
	setlinebuf(stdout);

#ifdef UDHCP_SYSLOG
	openlog(client_server, LOG_PID | LOG_CONS, LOG_LOCAL0);
#endif

	udhcp_logging(LOG_INFO, "%s (v%s) started", client_server, VERSION);
}