Merge branch 'collectd-5.7' into collectd-5.8

[collectd.git] / src / lvm.c

diff --git a/src/lvm.c b/src/lvm.c
index f6ca577..3ec79de 100644 (file)
--- a/src/lvm.c
+++ b/src/lvm.c
@@ -18,16 +18,20 @@
  *
  * Authors:
  *   Chad Malfait <malfaitc at yahoo.com>
- *   Benjamin Gilbert <bgilbert at cs.cmu.edu>
+ *   Benjamin Gilbert <bgilbert at backtick.net>
  **/
 
-#include <lvm2app.h>
-
 #include "collectd.h"
 
 #include "common.h"
 #include "plugin.h"
 
+#include <lvm2app.h>
+
+#ifdef HAVE_SYS_CAPABILITY_H
+#include <sys/capability.h>
+#endif /* HAVE_SYS_CAPABILITY_H */
+
 #define NO_VALUE UINT64_MAX
 #define PERCENT_SCALE_FACTOR 1e-8
 
@@ -52,15 +56,11 @@ static char const *get_lv_property_string(lv_t lv, char const *property) {
 
 static void lvm_submit(char const *plugin_instance, char const *type_instance,
                        uint64_t ivalue) {
-  value_t v;
   value_list_t vl = VALUE_LIST_INIT;
 
-  v.gauge = (gauge_t)ivalue;
-
-  vl.values = &v;
+  vl.values = &(value_t){.gauge = (gauge_t)ivalue};
   vl.values_len = 1;
 
-  sstrncpy(vl.host, hostname_g, sizeof(vl.host));
   sstrncpy(vl.plugin, "lvm", sizeof(vl.plugin));
   sstrncpy(vl.plugin_instance, plugin_instance, sizeof(vl.plugin_instance));
   sstrncpy(vl.type, "df_complex", sizeof(vl.type));
@@ -81,8 +81,7 @@ static void report_lv_utilization(lv_t lv, char const *vg_name,
     return;
   used_bytes = lv_size * (used_percent_unscaled * PERCENT_SCALE_FACTOR);
 
-  ssnprintf(plugin_instance, sizeof(plugin_instance), "%s-%s", vg_name,
-            lv_name);
+  snprintf(plugin_instance, sizeof(plugin_instance), "%s-%s", vg_name, lv_name);
   lvm_submit(plugin_instance, "used", used_bytes);
   lvm_submit(plugin_instance, "free", lv_size - used_bytes);
 }
@@ -160,14 +159,14 @@ static int lvm_read(void) {
   lvm = lvm_init(NULL);
   if (!lvm) {
     ERROR("lvm plugin: lvm_init failed.");
-    return (-1);
+    return -1;
   }
 
   vg_names = lvm_list_vg_names(lvm);
   if (!vg_names) {
     ERROR("lvm plugin lvm_list_vg_name failed %s", lvm_errmsg(lvm));
     lvm_quit(lvm);
-    return (-1);
+    return -1;
   }
 
   dm_list_iterate_items(name_list, vg_names) {
@@ -185,9 +184,27 @@ static int lvm_read(void) {
   }
 
   lvm_quit(lvm);
-  return (0);
+  return 0;
 } /*lvm_read */
 
+static int c_lvm_init(void) {
+#if defined(HAVE_SYS_CAPABILITY_H) && defined(CAP_SYS_ADMIN)
+  if (check_capability(CAP_SYS_ADMIN) != 0) {
+    if (getuid() == 0)
+      WARNING("lvm plugin: Running collectd as root, but the "
+              "CAP_SYS_ADMIN capability is missing. The plugin's read "
+              "function will probably fail. Is your init system dropping "
+              "capabilities?");
+    else
+      WARNING("lvm plugin: collectd doesn't have the CAP_SYS_ADMIN "
+              "capability. If you don't want to run collectd as root, try "
+              "running \"setcap cap_sys_admin=ep\" on the collectd binary.");
+  }
+#endif
+  return 0;
+}
+
 void module_register(void) {
+  plugin_register_init("lvm", c_lvm_init);
   plugin_register_read("lvm", lvm_read);
 } /* void module_register */