sensors plugin: Simplify the reload machanism.

[collectd.git] / src / sensors.c

diff --git a/src/sensors.c b/src/sensors.c
index 7c05b7a..d15569c 100644 (file)
--- a/src/sensors.c
+++ b/src/sensors.c
@@ -179,17 +179,17 @@ static ignorelist_t *sensor_list;
 static int sensor_extended_naming = 0;
 
 #if SENSORS_HAVE_READ
-#ifndef SENSORS_CONF_PATH
-# define SENSORS_CONF_PATH "/etc/sensors.conf"
-#endif
+#  ifndef SENSORS_CONF_PATH
+#    define SENSORS_CONF_PATH "/etc/sensors.conf"
+#  endif
+
 static const char *conffile = SENSORS_CONF_PATH;
 /* SENSORS_CONF_PATH */
 
 /*
  * remember stat of the loaded config
  */
-static struct stat sensors_conf_stat;
-static int sensors_conf_loaded = 0;
+static time_t sensors_config_mtime = 0;
 
 typedef struct featurelist
 {
@@ -246,11 +246,10 @@ void sensors_free_features (void)
        featurelist_t *thisft;
        featurelist_t *nextft;
 
-       if (sensors_conf_loaded)
-       {
-               sensors_cleanup ();
-               sensors_conf_loaded = 0;
-       }
+       if (first_feature == NULL)
+               return;
+
+       sensors_cleanup ();
 
        for (thisft = first_feature; thisft != NULL; thisft = nextft)
        {
@@ -260,51 +259,59 @@ void sensors_free_features (void)
        first_feature = NULL;
 }
 
-static void sensors_load_conf (int firsttime)
+static void sensors_load_conf (void)
 {
        FILE *fh;
        featurelist_t *last_feature = NULL;
-       featurelist_t *new_feature;
+       featurelist_t *new_feature = NULL;
        
        const sensors_chip_name *chip;
        int chip_num;
 
        const sensors_feature_data *data;
        int data_num0, data_num1;
+
+       struct stat statbuf;
+       int status;
        
-       sensors_free_features ();
-       new_feature = first_feature;
+       status = stat (conffile, &statbuf);
+       if (status != 0)
+       {
+               syslog (LOG_ERR, MODULE_NAME": stat(%s) failed: %s",
+                               conffile, strerror (errno));
+               sensors_config_mtime = 0;
+       }
 
-#ifdef assert
-       assert (new_feature == NULL);
-       assert (last_feature == NULL);
-#endif
+       if ((sensors_config_mtime != 0)
+                       && (sensors_config_mtime == statbuf.st_mtime))
+               return;
 
-       if ((fh = fopen (conffile, "r")) == NULL)
+       if (sensors_config_mtime != 0)
        {
-               syslog (LOG_ERR, MODULE_NAME": cannot open %s: %s. "
-                               "Data will not be collected.", conffile, strerror(errno));
-               return;
+               syslog (LOG_NOTICE, MODULE_NAME": Reloading config from %s",
+                               conffile);
+               sensors_free_features ();
+               sensors_config_mtime = 0;
        }
 
-       if (sensors_init (fh))
+       fh = fopen (conffile, "r");
+       if (fh == NULL)
        {
-               fclose (fh);
-               syslog (LOG_ERR, MODULE_NAME": Cannot initialize sensors. "
-                               "Data will not be collected.");
+               syslog (LOG_ERR, MODULE_NAME": fopen(%s) failed: %s",
+                               conffile, strerror(errno));
                return;
        }
 
-       /* remember file status to detect changes */
-       if (fstat (fileno (fh), &sensors_conf_stat) == -1)
+       status = sensors_init (fh);
+       fclose (fh);
+       if (status != 0)
        {
-               fclose (fh);
-               syslog (LOG_ERR, MODULE_NAME": cannot fstat %s: %s "
-                               "Data will not be collected.", conffile, strerror(errno));
+               syslog (LOG_ERR, MODULE_NAME": Cannot initialize sensors. "
+                               "Data will not be collected.");
                return;
        }
 
-       fclose (fh);
+       sensors_config_mtime = statbuf.st_mtime;
 
        chip_num = 0;
        while ((chip = sensors_get_detected_chips (&chip_num)) != NULL)
@@ -366,26 +373,18 @@ static void sensors_load_conf (int firsttime)
                } /* while sensors_get_all_features */
        } /* while sensors_get_detected_chips */
 
-       if (!firsttime)
-               syslog (LOG_INFO, MODULE_NAME": lm_sensors' configuration reloaded.");
-
        if (first_feature == NULL)
        {
                sensors_cleanup ();
-               sensors_conf_loaded = 0;
                syslog (LOG_INFO, MODULE_NAME": lm_sensors reports no features. "
                        "Data will not be collected.");
        }
-       else
-               sensors_conf_loaded = 1;
-}
+} /* void sensors_load_conf */
 #endif /* if SENSORS_HAVE_READ */
 
 static void collectd_sensors_init (void)
 {
-#if SENSORS_HAVE_READ
-       sensors_load_conf (1);
-#endif /* if SENSORS_HAVE_READ */
+       return;
 }
 
 static void sensors_shutdown (void)
@@ -477,31 +476,8 @@ static void sensors_read (void)
        featurelist_t *feature;
        double value;
        char chip_fullprefix[BUFSIZE];
-       struct stat changedbuf;
 
-       /* check sensors.conf for changes */
-       if (sensors_conf_loaded)
-       {
-               if (stat (conffile, &changedbuf) == -1)
-               {
-                       syslog (LOG_ERR, MODULE_NAME": cannot stat %s: %s",
-                                       conffile, strerror(errno));
-                       /*
-                        * sensors.conf does not exist,
-                        * throw away previous conf
-                        */
-                       sensors_load_conf (0);
-               }
-               else
-               {
-                       if ((changedbuf.st_size != sensors_conf_stat.st_size) ||
-                                       (changedbuf.st_mtime != sensors_conf_stat.st_mtime) ||
-                                       (changedbuf.st_ino != sensors_conf_stat.st_ino))
-                       {
-                               sensors_load_conf (0);
-                       }
-               }
-       }
+       sensors_load_conf ();
 
        for (feature = first_feature; feature != NULL; feature = feature->next)
        {
@@ -551,8 +527,8 @@ static void sensors_read (void)
                                        feature->chip->prefix,
                                        value, feature->type);
                }
-       }
-}
+       } /* for feature = first_feature .. NULL */
+} /* void sensors_read */
 #else
 # define sensors_read NULL
 #endif /* SENSORS_HAVE_READ */