diag.c revision 1.9 
1/*	$NetBSD: diag.c,v 1.9 2012/03/21 10:10:37 matt Exp $	*/
2
3 /*
4  * Routines to report various classes of problems. Each report is decorated
5  * with the current context (file name and line number), if available.
6  *
7  * tcpd_warn() reports a problem and proceeds.
8  *
9  * tcpd_jump() reports a problem and jumps.
10  *
11  * Author: Wietse Venema, Eindhoven University of Technology, The Netherlands.
12  */
13
14#include <sys/cdefs.h>
15#ifndef lint
16#if 0
17static char sccsid[] = "@(#) diag.c 1.1 94/12/28 17:42:20";
18#else
19__RCSID("$NetBSD: diag.c,v 1.9 2012/03/21 10:10:37 matt Exp $");
20#endif
21#endif
22
23/* System libraries */
24
25#include <syslog.h>
26#include <stdarg.h>
27#include <stdio.h>
28#include <setjmp.h>
29#include <string.h>
30#include <errno.h>
31
32/* Local stuff */
33
34#include "tcpd.h"
35
36struct tcpd_context tcpd_context;
37jmp_buf tcpd_buf;
38
39static void tcpd_diag(int, const char *, const char *, va_list)
40	__attribute__((__format__(__printf__, 3, 0)));
41
42/* tcpd_diag - centralize error reporter */
43
44static void
45tcpd_diag(int severity, const char *tag, const char *format, va_list ap)
46{
47    char    fmt[BUFSIZ];
48    char    buf[BUFSIZ];
49    size_t  i, o;
50    int     oerrno;
51
52    /* save errno in case we need it */
53    oerrno = errno;
54
55    /* contruct the tag for the log entry */
56    if (tcpd_context.file)
57	(void)snprintf(buf, sizeof buf, "%s: %s, line %d: ",
58		tag, tcpd_context.file, tcpd_context.line);
59    else
60	(void)snprintf(buf, sizeof buf, "%s: ", tag);
61
62    /* change % to %% in tag before appending the format */
63    for (i = 0, o = 0; buf[i] != '\0'; ) {
64	if (buf[i] == '%') {
65	    fmt[o] = '%';
66	    if (o < sizeof(fmt) - 1)
67		o++;
68	}
69	fmt[o] = buf[i++];
70	if (o < sizeof(fmt) - 1)
71	    o++;
72    }
73
74    /* append format and force null termination */
75    fmt[o] = '\0';
76    (void)strlcat(fmt, format, sizeof(fmt) - o);
77
78    errno = oerrno;
79    vsyslog(severity, fmt, ap);
80}
81
82/* tcpd_warn - report problem of some sort and proceed */
83
84void
85tcpd_warn(const char *format, ...)
86{
87    va_list ap;
88
89    va_start(ap, format);
90    tcpd_diag(LOG_ERR, "warning", format, ap);
91    va_end(ap);
92}
93
94/* tcpd_jump - report serious problem and jump */
95
96void
97tcpd_jump(const char *format, ...)
98{
99    va_list ap;
100
101    va_start(ap, format);
102    tcpd_diag(LOG_ERR, "error", format, ap);
103    va_end(ap);
104    longjmp(tcpd_buf, AC_ERROR);
105}
106