1 /**
2 * collectd - src/users.c
3 * Copyright (C) 2005,2006 Sebastian Harl
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License as published by the
7 * Free Software Foundation; either version 2 of the License, or (at your
8 * option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
18 *
19 * Authors:
20 * Sebastian Harl <sh at tokkee.org>
21 **/
23 #include "collectd.h"
24 #include "common.h"
25 #include "plugin.h"
27 #if HAVE_UTMPX_H
28 # include <utmpx.h>
29 #else /* !HAVE_UTMPX_H */
30 # if HAVE_UTMP_H
31 # include <utmp.h>
32 # endif /* HAVE_UTMP_H */
33 #endif /* HAVE_UTMPX_H */
35 #define MODULE_NAME "users"
37 #if HAVE_GETUTXENT || HAVE_GETUTENT
38 # define USERS_HAVE_READ 1
39 #else
40 # define USERS_HAVE_READ 0
41 #endif
43 static char *rrd_file = "users.rrd";
44 static char *ds_def[] =
45 {
46 "DS:users:GAUGE:"COLLECTD_HEARTBEAT":0:65535",
47 NULL
48 };
49 static int ds_num = 1;
51 static void users_init (void)
52 {
53 /* we have nothing to do here :-) */
54 return;
55 } /* static void users_init(void) */
57 static void users_write (char *host, char *inst, char *val)
58 {
59 rrd_update_file(host, rrd_file, val, ds_def, ds_num);
60 return;
61 } /* static void users_write(char *host, char *inst, char *val) */
63 #if USERS_HAVE_READ
64 /* I don't like this temporary macro definition - well it's used everywhere
65 else in the collectd-sources, so I will just stick with it... */
66 #define BUFSIZE 256
67 static void users_submit (unsigned int users)
68 {
69 char buf[BUFSIZE] = "";
71 if (snprintf(buf, BUFSIZE, "%u:%u",
72 (unsigned int)curtime, users) >= BUFSIZE)
73 {
74 return;
75 }
77 plugin_submit(MODULE_NAME, NULL, buf);
78 return;
79 } /* static void users_submit(unsigned int users) */
80 #undef BUFSIZE
82 static void users_read (void)
83 {
84 #if HAVE_GETUTXENT
85 unsigned int users = 0;
86 struct utmpx *entry = NULL;
88 /* according to the *utent(3) man page none of the functions sets errno
89 in case of an error, so we cannot do any error-checking here */
90 setutxent();
92 while (NULL != (entry = getutxent())) {
93 if (USER_PROCESS == entry->ut_type) {
94 ++users;
95 }
96 }
97 endutxent();
99 users_submit (users);
100 /* #endif HAVE_GETUTXENT */
102 #elif HAVE_GETUTENT
103 unsigned int users = 0;
104 struct utmp *entry = NULL;
106 /* according to the *utent(3) man page none of the functions sets errno
107 in case of an error, so we cannot do any error-checking here */
108 setutent();
110 while (NULL != (entry = getutent())) {
111 if (USER_PROCESS == entry->ut_type) {
112 ++users;
113 }
114 }
115 endutent();
117 users_submit(users);
118 #endif /* HAVE_GETUTENT */
120 return;
121 } /* static void users_read(void) */
122 #else
123 # define users_read NULL
124 #endif /* USERS_HAVE_READ */
126 void module_register (void)
127 {
128 plugin_register (MODULE_NAME, users_init, users_read, users_write);
129 return;
130 } /* void module_register(void) */