1 /**
2 * collectd - src/uptime.c
3 * Copyright (C) 2009 Marco Chiappero
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; only version 2 of the License is applicable.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
17 *
18 * Authors:
19 * Marco Chiappero <marco at absence.it>
20 **/
22 #include "collectd.h"
23 #include "common.h"
24 #include "plugin.h"
26 #if KERNEL_LINUX
27 # define UPTIME_FILE "/proc/uptime"
28 /*
29 No need for includes, using /proc filesystem, Linux only.
30 */
31 /* #endif KERNEL_LINUX */
33 #elif HAVE_LIBKSTAT
34 /* something to include? maybe <sys/sysinfo.h> ? */
35 /*
36 Using kstats chain to retrieve the boot time, this applies to:
37 - Solaris / OpenSolaris
38 */
39 /* #endif HAVE_LIBKSTAT */
41 #elif HAVE_SYS_SYSCTL_H
42 # include <sys/sysctl.h>
43 /*
44 Using sysctl interface to retrieve the boot time, this applies to:
45 - *BSD
46 - Darwin / OS X
47 */
48 /* #endif HAVE_SYS_SYSCTL_H */
50 #else
51 # error "No applicable input method."
52 #endif
55 #if !KERNEL_LINUX
56 #define INIT_FAILED "uptime plugin: unable to calculate uptime, the plugin will be disabled."
57 #endif
60 #if KERNEL_LINUX
61 /* global variables not needed*/
63 #elif HAVE_SYS_SYSCTL_H || HAVE_LIBKSTAT
64 static time_t boottime;
65 # if HAVE_LIBKSTAT
66 extern kstat_ctl_t *kc;
67 # endif
69 #endif
72 static void uptime_submit (gauge_t uptime)
73 {
74 value_t values[1];
75 value_list_t vl = VALUE_LIST_INIT;
77 values[0].gauge = uptime;
79 vl.values = values;
80 vl.values_len = 1;
81 vl.time = time (NULL);
83 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
84 sstrncpy (vl.plugin, "uptime", sizeof (vl.plugin));
85 sstrncpy (vl.type, "uptime", sizeof (vl.type));
87 plugin_dispatch_values (&vl);
88 }
90 #if !KERNEL_LINUX
91 static int uptime_init (void)
92 {
93 /* NOTE
95 On unix systems other than Linux there is no /proc filesystem which
96 calculates the uptime every time we call a read for the /proc/uptime
97 file, the only information available is the boot time (in unix time,
98 since epoch). Hence there is no need to read, every time the
99 plugin_read is called, a value that won't change: this is a right
100 task for the uptime_init function. However, since uptime_init is run
101 only once, if the function fails in retrieving the boot time, the
102 plugin is unregistered and there is no chance to try again later.
103 Nevertheless, this is very unlikely to happen.
105 */
107 # if HAVE_LIBKSTAT
109 kstat_t *ksp;
110 kstat_named_t *knp;
112 ksp = NULL;
113 knp = NULL;
115 /* kstats chain already opened by update_kstat (using *kc), let's verify everything went fine. */
116 if ( kc == NULL )
117 {
118 ERROR ("uptime plugin: unable to open kstat control structure");
119 ERROR (INIT_FAILED);
120 return (-1);
121 }
123 if (( ksp = kstat_lookup (kc, "unix", 0, "system_misc")) == NULL )
124 {
125 ERROR ("uptime plugin: cannot find %s kstat", "unix:0:system_misc");
126 ERROR (INIT_FAILED);
127 return (-1);
128 }
130 if (( kstat_read (kc, ksp, NULL) < 0 ) ||
131 (( knp = (kstat_named_t *) kstat_data_lookup (ksp, "boot_time")) != NULL ))
132 {
133 ERROR ("uptime plugin: kstat data reading failed");
134 ERROR (INIT_FAILED);
135 return (-1);
136 }
138 boottime = (time_t) knp->value.ui32;
140 /* #endif HAVE_LIBKSTAT */
142 # elif HAVE_SYS_SYSCTL_H
144 struct timeval boottv;
145 size_t boottv_len;
147 int mib[2];
149 mib[0] = CTL_KERN;
150 mib[1] = KERN_BOOTTIME;
152 boottv_len = sizeof (boottv);
154 if (( sysctl (mib, 2, &boottv, &boottv_len, NULL, 0) != 0 ) || boottv.tv_sec == 0 )
155 {
156 char errbuf[1024];
157 ERROR ("uptime plugin: no value read from sysctl interface: %s",
158 sstrerror (errno, errbuf, sizeof (errbuf)));
159 ERROR (INIT_FAILED);
160 return (-1);
161 }
163 boottime = boottv.tv_sec;
165 /* #endif HAVE_SYS_SYSCTL_H */
167 # endif
169 return (0);
171 }
172 #endif
174 static int uptime_read (void)
175 {
176 gauge_t uptime;
178 #if KERNEL_LINUX
180 FILE *fh;
182 fh = fopen (UPTIME_FILE, "r");
184 if (fh == NULL)
185 {
186 char errbuf[1024];
187 ERROR ("uptime plugin: cannot open %s: %s", UPTIME_FILE,
188 sstrerror (errno, errbuf, sizeof (errbuf)));
189 return (-1);
190 }
192 if ( fscanf (fh, "%lf", &uptime) < 1 )
193 {
194 WARNING ("no value read from %s", UPTIME_FILE);
195 fclose (fh);
196 return (-1);
197 }
199 fclose (fh);
201 /* #endif KERNEL_LINUX */
204 #elif HAVE_SYS_SYSCTL_H || HAVE_LIBKSTAT
206 time_t elapsed;
208 elapsed = time (NULL) - boottime;
210 uptime = (gauge_t) elapsed;
212 /* #endif HAVE_SYS_SYSCTL_H */
214 #endif
216 uptime_submit (uptime);
218 return (0);
219 }
221 void module_register (void)
222 {
223 #if !KERNEL_LINUX
224 plugin_register_init ("uptime", uptime_init);
225 #endif
226 plugin_register_read ("uptime", uptime_read);
227 } /* void module_register */