X-Git-Url: https://git.octo.it/?p=collectd.git;a=blobdiff_plain;f=src%2Fconnectivity.c;h=45b65aab5b09c1c5ba35110bbff618f6144de153;hp=f6356f03987275ffb888589b112d5ee19c18cfbc;hb=48efd3deb4c9139fd060ff3d289896e9031bcc7c;hpb=7023393d66c024facbcc5f6603e52bc86a6a930e

diff --git a/src/connectivity.c b/src/connectivity.c
index f6356f03..45b65aab 100644
--- a/src/connectivity.c
+++ b/src/connectivity.c
@@ -27,10 +27,10 @@
 
 #include "collectd.h"
 
-#include "common.h"
 #include "plugin.h"
+#include "utils/common/common.h"
+#include "utils/ignorelist/ignorelist.h"
 #include "utils_complain.h"
-#include "utils_ignorelist.h"
 
 #include <asm/types.h>
 #include <errno.h>
@@ -101,7 +101,7 @@ struct interface_list_s {
   uint32_t status;
   uint32_t prev_status;
   uint32_t sent;
-  long long unsigned int timestamp;
+  cdtime_t timestamp;
 
   struct interface_list_s *next;
 };
@@ -120,40 +120,29 @@ static int connectivity_netlink_thread_loop = 0;
 static int connectivity_netlink_thread_error = 0;
 static pthread_t connectivity_netlink_thread_id;
 static int connectivity_dequeue_thread_loop = 0;
-static int connectivity_dequeue_thread_error = 0;
 static pthread_t connectivity_dequeue_thread_id;
-static pthread_mutex_t connectivity_lock = PTHREAD_MUTEX_INITIALIZER;
+static pthread_mutex_t connectivity_threads_lock = PTHREAD_MUTEX_INITIALIZER;
+static pthread_mutex_t connectivity_data_lock = PTHREAD_MUTEX_INITIALIZER;
 static pthread_cond_t connectivity_cond = PTHREAD_COND_INITIALIZER;
-// static struct mnl_socket *sock;
 static int nl_sock = -1;
 static int event_id = 0;
+static int statuses_to_send = 0;
 
 static const char *config_keys[] = {"Interface", "IgnoreSelected"};
 static int config_keys_num = STATIC_ARRAY_SIZE(config_keys);
 
 /*
- * Prototype
- */
-
-static void
-connectivity_dispatch_notification(const char *interface, const char *type,
-                                   gauge_t value, gauge_t old_value,
-                                   long long unsigned int timestamp);
-
-/*
  * Private functions
  */
 
 static int gen_message_payload(int state, int old_state, const char *interface,
-                               long long unsigned int timestamp, char **buf) {
+                               cdtime_t timestamp, char **buf) {
   const unsigned char *buf2;
   yajl_gen g;
   char json_str[DATA_MAX_NAME_LEN];
 
 #if !defined(HAVE_YAJL_V2)
-  yajl_gen_config conf = {};
-
-  conf.beautify = 0;
+  yajl_gen_config conf = {0};
 #endif
 
 #if HAVE_YAJL_V2
@@ -188,9 +177,9 @@ static int gen_message_payload(int state, int old_state, const char *interface,
     goto err;
 
   event_id = event_id + 1;
-  int event_id_len = sizeof(char) * sizeof(int) * 4 + 1;
-  memset(json_str, '\0', DATA_MAX_NAME_LEN);
-  snprintf(json_str, event_id_len, "%d", event_id);
+  if (snprintf(json_str, sizeof(json_str), "%d", event_id) < 0) {
+    goto err;
+  }
 
   if (yajl_gen_number(g, json_str, strlen(json_str)) != yajl_gen_status_ok) {
     goto err;
@@ -202,15 +191,11 @@ static int gen_message_payload(int state, int old_state, const char *interface,
       yajl_gen_status_ok)
     goto err;
 
-  int event_name_len = 0;
-  event_name_len = event_name_len + strlen(interface);    // interface name
-  event_name_len = event_name_len + (state == 0 ? 4 : 2); // "down" or "up"
-  event_name_len =
-      event_name_len + 12; // "interface", 2 spaces and null-terminator
-  memset(json_str, '\0', DATA_MAX_NAME_LEN);
-  snprintf(json_str, event_name_len, "interface %s %s", interface,
-           (state == 0 ? CONNECTIVITY_EVENT_NAME_DOWN_VALUE
-                       : CONNECTIVITY_EVENT_NAME_UP_VALUE));
+  if (snprintf(json_str, sizeof(json_str), "interface %s %s", interface,
+               (state == 0 ? CONNECTIVITY_EVENT_NAME_DOWN_VALUE
+                           : CONNECTIVITY_EVENT_NAME_UP_VALUE)) < 0) {
+    goto err;
+  }
 
   if (yajl_gen_string(g, (u_char *)json_str, strlen(json_str)) !=
       yajl_gen_status_ok) {
@@ -223,11 +208,10 @@ static int gen_message_payload(int state, int old_state, const char *interface,
       yajl_gen_status_ok)
     goto err;
 
-  int last_epoch_microsec_len =
-      sizeof(char) * sizeof(long long unsigned int) * 4 + 1;
-  memset(json_str, '\0', DATA_MAX_NAME_LEN);
-  snprintf(json_str, last_epoch_microsec_len, "%llu",
-           (long long unsigned int)CDTIME_T_TO_US(cdtime()));
+  if (snprintf(json_str, sizeof(json_str), "%" PRIu64,
+               CDTIME_T_TO_US(cdtime())) < 0) {
+    goto err;
+  }
 
   if (yajl_gen_number(g, json_str, strlen(json_str)) != yajl_gen_status_ok) {
     goto err;
@@ -282,11 +266,10 @@ static int gen_message_payload(int state, int old_state, const char *interface,
       yajl_gen_status_ok)
     goto err;
 
-  int start_epoch_microsec_len =
-      sizeof(char) * sizeof(long long unsigned int) * 4 + 1;
-  memset(json_str, '\0', DATA_MAX_NAME_LEN);
-  snprintf(json_str, start_epoch_microsec_len, "%llu",
-           (long long unsigned int)timestamp);
+  if (snprintf(json_str, sizeof(json_str), "%" PRIu64,
+               CDTIME_T_TO_US(timestamp)) < 0) {
+    goto err;
+  }
 
   if (yajl_gen_number(g, json_str, strlen(json_str)) != yajl_gen_status_ok) {
     goto err;
@@ -323,10 +306,11 @@ static int gen_message_payload(int state, int old_state, const char *interface,
       (state == 0 ? strlen(CONNECTIVITY_NEW_STATE_FIELD_DOWN_VALUE)
                   : strlen(CONNECTIVITY_NEW_STATE_FIELD_UP_VALUE));
 
-  if (yajl_gen_string(
-          g, (u_char *)(state == 0 ? CONNECTIVITY_NEW_STATE_FIELD_DOWN_VALUE
-                                   : CONNECTIVITY_NEW_STATE_FIELD_UP_VALUE),
-          new_state_len) != yajl_gen_status_ok)
+  if (yajl_gen_string(g,
+                      (u_char *)(state == 0
+                                     ? CONNECTIVITY_NEW_STATE_FIELD_DOWN_VALUE
+                                     : CONNECTIVITY_NEW_STATE_FIELD_UP_VALUE),
+                      new_state_len) != yajl_gen_status_ok)
     goto err;
 
   // oldState
@@ -339,10 +323,11 @@ static int gen_message_payload(int state, int old_state, const char *interface,
       (old_state == 0 ? strlen(CONNECTIVITY_OLD_STATE_FIELD_DOWN_VALUE)
                       : strlen(CONNECTIVITY_OLD_STATE_FIELD_UP_VALUE));
 
-  if (yajl_gen_string(
-          g, (u_char *)(old_state == 0 ? CONNECTIVITY_OLD_STATE_FIELD_DOWN_VALUE
-                                       : CONNECTIVITY_OLD_STATE_FIELD_UP_VALUE),
-          old_state_len) != yajl_gen_status_ok)
+  if (yajl_gen_string(g,
+                      (u_char *)(old_state == 0
+                                     ? CONNECTIVITY_OLD_STATE_FIELD_DOWN_VALUE
+                                     : CONNECTIVITY_OLD_STATE_FIELD_UP_VALUE),
+                      old_state_len) != yajl_gen_status_ok)
     goto err;
 
   // stateChangeFieldsVersion
@@ -367,28 +352,24 @@ static int gen_message_payload(int state, int old_state, const char *interface,
       yajl_gen_status_ok)
     goto err;
 
-  if (yajl_gen_map_close(g) != yajl_gen_status_ok)
+  // close state change and header fields
+  if (yajl_gen_map_close(g) != yajl_gen_status_ok ||
+      yajl_gen_map_close(g) != yajl_gen_status_ok)
     goto err;
 
   // *** END state change fields ***
 
-  if (yajl_gen_map_close(g) != yajl_gen_status_ok)
-    goto err;
-
   if (yajl_gen_get_buf(g, &buf2, &len) != yajl_gen_status_ok)
     goto err;
 
-  *buf = malloc(strlen((char *)buf2) + 1);
+  *buf = strdup((char *)buf2);
 
   if (*buf == NULL) {
-    char errbuf[1024];
-    ERROR("connectivity plugin: malloc failed during gen_message_payload: %s",
-          sstrerror(errno, errbuf, sizeof(errbuf)));
+    ERROR("connectivity plugin: strdup failed during gen_message_payload: %s",
+          STRERRNO);
     goto err;
   }
 
-  sstrncpy(*buf, (char *)buf2, strlen((char *)buf2) + 1);
-
   yajl_gen_free(g);
 
   return 0;
@@ -401,30 +382,26 @@ err:
 
 static interface_list_t *add_interface(const char *interface, int status,
                                        int prev_status) {
-  interface_list_t *il;
-  char *interface2;
+  interface_list_t *il = calloc(1, sizeof(*il));
 
-  il = malloc(sizeof(*il));
   if (il == NULL) {
-    char errbuf[1024];
-    ERROR("connectivity plugin: malloc failed during add_interface: %s",
-          sstrerror(errno, errbuf, sizeof(errbuf)));
+    ERROR("connectivity plugin: calloc failed during add_interface: %s",
+          STRERRNO);
     return NULL;
   }
 
-  interface2 = strdup(interface);
+  char *interface2 = strdup(interface);
   if (interface2 == NULL) {
-    char errbuf[1024];
     sfree(il);
     ERROR("connectivity plugin: strdup failed during add_interface: %s",
-          sstrerror(errno, errbuf, sizeof(errbuf)));
+          STRERRNO);
     return NULL;
   }
 
   il->interface = interface2;
   il->status = status;
   il->prev_status = prev_status;
-  il->timestamp = (long long unsigned int)CDTIME_T_TO_US(cdtime());
+  il->timestamp = cdtime();
   il->sent = 0;
   il->next = interface_list_head;
   interface_list_head = il;
@@ -435,14 +412,10 @@ static interface_list_t *add_interface(const char *interface, int status,
 }
 
 static int connectivity_link_state(struct nlmsghdr *msg) {
-  int retval = 0;
-  struct ifinfomsg *ifi = mnl_nlmsg_get_payload(msg);
-  struct nlattr *attr;
-  const char *dev = NULL;
+  pthread_mutex_lock(&connectivity_data_lock);
 
-  pthread_mutex_lock(&connectivity_lock);
-
-  interface_list_t *il = NULL;
+  struct nlattr *attr;
+  struct ifinfomsg *ifi = mnl_nlmsg_get_payload(msg);
 
   /* Scan attribute list for device name. */
   mnl_attr_for_each(attr, msg, sizeof(*ifi)) {
@@ -453,11 +426,11 @@ static int connectivity_link_state(struct nlmsghdr *msg) {
       ERROR("connectivity plugin: connectivity_link_state: IFLA_IFNAME "
             "mnl_attr_validate "
             "failed.");
-      pthread_mutex_unlock(&connectivity_lock);
+      pthread_mutex_unlock(&connectivity_data_lock);
       return MNL_CB_ERROR;
     }
 
-    dev = mnl_attr_get_str(attr);
+    const char *dev = mnl_attr_get_str(attr);
 
     // Check the list of interfaces we should monitor, if we've chosen
     // a subset.  If we don't care about this one, abort.
@@ -468,12 +441,12 @@ static int connectivity_link_state(struct nlmsghdr *msg) {
       break;
     }
 
+    interface_list_t *il = NULL;
+
     for (il = interface_list_head; il != NULL; il = il->next)
       if (strcmp(dev, il->interface) == 0)
         break;
 
-    uint32_t prev_status;
-
     if (il == NULL) {
       // We haven't encountered this interface yet, so add it to the linked list
       il = add_interface(dev, LINK_STATE_UNKNOWN, LINK_STATE_UNKNOWN);
@@ -486,20 +459,23 @@ static int connectivity_link_state(struct nlmsghdr *msg) {
       }
     }
 
-    prev_status = il->status;
+    uint32_t prev_status = il->status;
     il->status =
         ((ifi->ifi_flags & IFF_RUNNING) ? LINK_STATE_UP : LINK_STATE_DOWN);
-    il->timestamp = (long long unsigned int)CDTIME_T_TO_US(cdtime());
+    il->timestamp = cdtime();
 
     // If the new status is different than the previous status,
-    // store the previous status and set sent to zero
+    // store the previous status and set sent to zero, and set the
+    // global flag to indicate there are statuses to dispatch
     if (il->status != prev_status) {
       il->prev_status = prev_status;
       il->sent = 0;
+      statuses_to_send = 1;
     }
 
     DEBUG("connectivity plugin (%llu): Interface %s status is now %s",
-          il->timestamp, dev, ((ifi->ifi_flags & IFF_RUNNING) ? "UP" : "DOWN"));
+          (unsigned long long)il->timestamp, dev,
+          ((ifi->ifi_flags & IFF_RUNNING) ? "UP" : "DOWN"));
 
     // no need to loop again, we found the interface name attr
     // (otherwise the first if-statement in the loop would
@@ -507,57 +483,38 @@ static int connectivity_link_state(struct nlmsghdr *msg) {
     break;
   }
 
-  pthread_mutex_unlock(&connectivity_lock);
+  pthread_mutex_unlock(&connectivity_data_lock);
 
-  return retval;
+  return 0;
 }
 
 static int msg_handler(struct nlmsghdr *msg) {
-  switch (msg->nlmsg_type) {
-  case RTM_NEWADDR:
-  case RTM_DELADDR:
-  case RTM_NEWROUTE:
-  case RTM_DELROUTE:
-  case RTM_DELLINK:
-    // Not of interest in current version
-    break;
-  case RTM_NEWLINK:
-    connectivity_link_state(msg);
-    break;
-  default:
-    ERROR("connectivity plugin: msg_handler: Unknown netlink nlmsg_type %d\n",
-          msg->nlmsg_type);
-    break;
+  // We are only interested in RTM_NEWLINK messages
+  if (msg->nlmsg_type != RTM_NEWLINK) {
+    return 0;
   }
-  return 0;
+  return connectivity_link_state(msg);
 }
 
-// static int read_event(struct mnl_socket *nl,
-//                       int (*msg_handler)(struct nlmsghdr *)) {
-static int read_event(int nl, int (*msg_handler)(struct nlmsghdr *)) {
-  int status;
+static int read_event(int (*msg_handler)(struct nlmsghdr *)) {
   int ret = 0;
-  char buf[4096];
-  struct nlmsghdr *h;
   int recv_flags = MSG_DONTWAIT;
 
-  // if (nl == NULL)
-  //   return ret;
-
-  if (nl == -1)
-    return ret;
+  if (nl_sock == -1 || msg_handler == NULL)
+    return EINVAL;
 
   while (42) {
-    pthread_mutex_lock(&connectivity_lock);
+    pthread_mutex_lock(&connectivity_threads_lock);
 
     if (connectivity_netlink_thread_loop <= 0) {
-      pthread_mutex_unlock(&connectivity_lock);
+      pthread_mutex_unlock(&connectivity_threads_lock);
       return ret;
     }
 
-    pthread_mutex_unlock(&connectivity_lock);
+    pthread_mutex_unlock(&connectivity_threads_lock);
 
-    status = recv(nl, buf, sizeof(buf), recv_flags);
+    char buf[4096];
+    int status = recv(nl_sock, buf, sizeof(buf), recv_flags);
 
     if (status < 0) {
 
@@ -566,19 +523,19 @@ static int read_event(int nl, int (*msg_handler)(struct nlmsghdr *)) {
       // any saved interface status changes.  Then continue, but
       // block and wait for new messages
       if (errno == EWOULDBLOCK || errno == EAGAIN) {
-        pthread_mutex_lock(&connectivity_lock);
         pthread_cond_signal(&connectivity_cond);
-        pthread_mutex_unlock(&connectivity_lock);
 
         recv_flags = 0;
         continue;
       }
 
+      if (errno == EINTR) {
+        // Interrupt, so just continue and try again
+        continue;
+      }
+
       /* Anything else is an error */
-      // ERROR("connectivity plugin: read_event: Error mnl_socket_recvfrom:
-      // %d\n",
-      //       status);
-      ERROR("connectivity plugin: read_event: Error recv: %d\n", status);
+      ERROR("connectivity plugin: read_event: Error recv: %d", status);
       return status;
     }
 
@@ -588,19 +545,21 @@ static int read_event(int nl, int (*msg_handler)(struct nlmsghdr *)) {
     recv_flags = MSG_DONTWAIT;
 
     if (status == 0) {
-      DEBUG("connectivity plugin: read_event: EOF\n");
+      DEBUG("connectivity plugin: read_event: EOF");
     }
 
     /* We need to handle more than one message per 'recvmsg' */
-    for (h = (struct nlmsghdr *)buf; NLMSG_OK(h, (unsigned int)status);
-         h = NLMSG_NEXT(h, status)) {
+    for (struct nlmsghdr *h = (struct nlmsghdr *)buf;
+         NLMSG_OK(h, (unsigned int)status); h = NLMSG_NEXT(h, status)) {
       /* Finish reading */
       if (h->nlmsg_type == NLMSG_DONE)
         return ret;
 
       /* Message is some kind of error */
       if (h->nlmsg_type == NLMSG_ERROR) {
-        ERROR("connectivity plugin: read_event: Message is an error\n");
+        struct nlmsgerr *l_err = (struct nlmsgerr *)NLMSG_DATA(h);
+        ERROR("connectivity plugin: read_event: Message is an error: %d",
+              l_err->error);
         return -1; // Error
       }
 
@@ -608,12 +567,12 @@ static int read_event(int nl, int (*msg_handler)(struct nlmsghdr *)) {
       if (msg_handler) {
         ret = (*msg_handler)(h);
         if (ret < 0) {
-          ERROR("connectivity plugin: read_event: Message handler error %d\n",
+          ERROR("connectivity plugin: read_event: Message handler error %d",
                 ret);
           return ret;
         }
       } else {
-        ERROR("connectivity plugin: read_event: Error NULL message handler\n");
+        ERROR("connectivity plugin: read_event: Error NULL message handler");
         return -1;
       }
     }
@@ -622,121 +581,138 @@ static int read_event(int nl, int (*msg_handler)(struct nlmsghdr *)) {
   return ret;
 }
 
+static void connectivity_dispatch_notification(const char *interface,
+                                               gauge_t value, gauge_t old_value,
+                                               cdtime_t timestamp) {
+
+  notification_t n = {
+      .severity = (value == LINK_STATE_UP ? NOTIF_OKAY : NOTIF_FAILURE),
+      .time = cdtime(),
+      .plugin = "connectivity",
+      .type = "gauge",
+      .type_instance = "interface_status",
+  };
+
+  sstrncpy(n.host, hostname_g, sizeof(n.host));
+  sstrncpy(n.plugin_instance, interface, sizeof(n.plugin_instance));
+
+  char *buf = NULL;
+
+  gen_message_payload(value, old_value, interface, timestamp, &buf);
+
+  int status = plugin_notification_meta_add_string(&n, "ves", buf);
+
+  if (status < 0) {
+    sfree(buf);
+    ERROR("connectivity plugin: unable to set notification VES metadata: %s",
+          STRERRNO);
+    return;
+  }
+
+  DEBUG("connectivity plugin: notification VES metadata: %s",
+        n.meta->nm_value.nm_string);
+
+  DEBUG("connectivity plugin: dispatching state %d for interface %s",
+        (int)value, interface);
+
+  plugin_dispatch_notification(&n);
+  plugin_notification_meta_free(n.meta);
+
+  // strdup'd in gen_message_payload
+  if (buf != NULL)
+    sfree(buf);
+}
+
+// NOTE: Caller MUST hold connectivity_data_lock when calling this function
 static void send_interface_status() {
   for (interface_list_t *il = interface_list_head; il != NULL;
        il = il->next) /* {{{ */
   {
-    uint32_t status;
-    uint32_t prev_status;
-    uint32_t sent;
-
-    status = il->status;
-    prev_status = il->prev_status;
-    sent = il->sent;
+    uint32_t status = il->status;
+    uint32_t prev_status = il->prev_status;
+    uint32_t sent = il->sent;
 
     if (status != prev_status && sent == 0) {
-      connectivity_dispatch_notification(il->interface, "gauge", status,
-                                         prev_status, il->timestamp);
+      connectivity_dispatch_notification(il->interface, status, prev_status,
+                                         il->timestamp);
       il->sent = 1;
     }
   } /* }}} for (il = interface_list_head; il != NULL; il = il->next) */
+
+  statuses_to_send = 0;
 }
 
-static int read_interface_status() /* {{{ */
+static void read_interface_status() /* {{{ */
 {
-  pthread_mutex_lock(&connectivity_lock);
-
-  // This first attempt is necessary because the netlink thread
-  // might have held the lock while this thread was blocked on
-  // the lock acquisition just above.  And while the netlink thread
-  // had the lock, it could have called pthread_cond_singal, which
-  // obviously wouldn't have woken this thread, since this thread
-  // was not yet waiting on the condition signal.  So we need to
-  // loop through the interfaces and check if any have changed
-  // status before we wait on the condition signal
-  send_interface_status();
+  pthread_mutex_lock(&connectivity_data_lock);
 
-  pthread_cond_wait(&connectivity_cond, &connectivity_lock);
+  // If we don't have any interface statuses to dispatch,
+  // then we wait until signalled
+  if (!statuses_to_send)
+    pthread_cond_wait(&connectivity_cond, &connectivity_data_lock);
 
   send_interface_status();
 
-  pthread_mutex_unlock(&connectivity_lock);
-
-  return 0;
+  pthread_mutex_unlock(&connectivity_data_lock);
 } /* }}} int *read_interface_status */
 
 static void *connectivity_netlink_thread(void *arg) /* {{{ */
 {
-  pthread_mutex_lock(&connectivity_lock);
+  pthread_mutex_lock(&connectivity_threads_lock);
 
   while (connectivity_netlink_thread_loop > 0) {
-    int status;
-
-    pthread_mutex_unlock(&connectivity_lock);
+    pthread_mutex_unlock(&connectivity_threads_lock);
 
-    status = read_event(nl_sock, msg_handler);
+    int status = read_event(msg_handler);
 
-    pthread_mutex_lock(&connectivity_lock);
+    pthread_mutex_lock(&connectivity_threads_lock);
 
     if (status < 0) {
       connectivity_netlink_thread_error = 1;
       break;
     }
-
-    if (connectivity_netlink_thread_loop <= 0)
-      break;
   } /* while (connectivity_netlink_thread_loop > 0) */
 
-  pthread_mutex_unlock(&connectivity_lock);
+  pthread_mutex_unlock(&connectivity_threads_lock);
 
-  return ((void *)0);
+  return (void *)0;
 } /* }}} void *connectivity_netlink_thread */
 
 static void *connectivity_dequeue_thread(void *arg) /* {{{ */
 {
-  pthread_mutex_lock(&connectivity_lock);
+  pthread_mutex_lock(&connectivity_threads_lock);
 
   while (connectivity_dequeue_thread_loop > 0) {
-    int status;
-
-    pthread_mutex_unlock(&connectivity_lock);
-
-    status = read_interface_status();
+    pthread_mutex_unlock(&connectivity_threads_lock);
 
-    pthread_mutex_lock(&connectivity_lock);
+    read_interface_status();
 
-    if (status < 0) {
-      connectivity_dequeue_thread_error = 1;
-      break;
-    }
-
-    if (connectivity_dequeue_thread_loop <= 0)
-      break;
+    pthread_mutex_lock(&connectivity_threads_lock);
   } /* while (connectivity_dequeue_thread_loop > 0) */
 
-  pthread_mutex_unlock(&connectivity_lock);
+  pthread_mutex_unlock(&connectivity_threads_lock);
 
   return ((void *)0);
 } /* }}} void *connectivity_dequeue_thread */
 
 static int nl_connect() {
-  int rc;
-  struct sockaddr_nl sa_nl;
+  struct sockaddr_nl sa_nl = {
+      .nl_family = AF_NETLINK,
+      .nl_groups = RTMGRP_LINK,
+      .nl_pid = getpid(),
+  };
 
   nl_sock = socket(AF_NETLINK, SOCK_DGRAM, NETLINK_ROUTE);
   if (nl_sock == -1) {
-    ERROR("connectivity plugin: socket open failed: %d", errno);
+    ERROR("connectivity plugin: socket open failed: %s", STRERRNO);
     return -1;
   }
 
-  sa_nl.nl_family = AF_NETLINK;
-  sa_nl.nl_groups = RTMGRP_LINK;
-  sa_nl.nl_pid = getpid();
-
-  rc = bind(nl_sock, (struct sockaddr *)&sa_nl, sizeof(sa_nl));
+  int rc = bind(nl_sock, (struct sockaddr *)&sa_nl, sizeof(sa_nl));
   if (rc == -1) {
-    ERROR("connectivity plugin: socket bind failed: %d", errno);
+    ERROR("connectivity plugin: socket bind failed: %s", STRERRNO);
     close(nl_sock);
+    nl_sock = -1;
     return -1;
   }
 
@@ -745,23 +721,25 @@ static int nl_connect() {
 
 static int start_netlink_thread(void) /* {{{ */
 {
-  int status;
-
-  pthread_mutex_lock(&connectivity_lock);
+  pthread_mutex_lock(&connectivity_threads_lock);
 
   if (connectivity_netlink_thread_loop != 0) {
-    pthread_mutex_unlock(&connectivity_lock);
-    return (0);
+    pthread_mutex_unlock(&connectivity_threads_lock);
+    return 0;
   }
 
   connectivity_netlink_thread_loop = 1;
   connectivity_netlink_thread_error = 0;
 
+  int status;
+
   if (nl_sock == -1) {
     status = nl_connect();
 
-    if (status != 0)
+    if (status != 0) {
+      pthread_mutex_unlock(&connectivity_threads_lock);
       return status;
+    }
   }
 
   status = plugin_thread_create(&connectivity_netlink_thread_id,
@@ -770,61 +748,58 @@ static int start_netlink_thread(void) /* {{{ */
   if (status != 0) {
     connectivity_netlink_thread_loop = 0;
     ERROR("connectivity plugin: Starting thread failed.");
-    pthread_mutex_unlock(&connectivity_lock);
+    pthread_mutex_unlock(&connectivity_threads_lock);
 
     int status2 = close(nl_sock);
 
     if (status2 != 0) {
       ERROR("connectivity plugin: failed to close socket %d: %d (%s)", nl_sock,
-            status2, strerror(errno));
-    } else
-      nl_sock = -1;
+            status2, STRERRNO);
+    }
 
-    return (-1);
+    nl_sock = -1;
+
+    return -1;
   }
 
-  pthread_mutex_unlock(&connectivity_lock);
+  pthread_mutex_unlock(&connectivity_threads_lock);
 
   return status;
 }
 
 static int start_dequeue_thread(void) /* {{{ */
 {
-  int status;
-
-  pthread_mutex_lock(&connectivity_lock);
+  pthread_mutex_lock(&connectivity_threads_lock);
 
   if (connectivity_dequeue_thread_loop != 0) {
-    pthread_mutex_unlock(&connectivity_lock);
-    return (0);
+    pthread_mutex_unlock(&connectivity_threads_lock);
+    return 0;
   }
 
   connectivity_dequeue_thread_loop = 1;
-  connectivity_dequeue_thread_error = 0;
 
-  status = plugin_thread_create(&connectivity_dequeue_thread_id,
-                                /* attr = */ NULL, connectivity_dequeue_thread,
-                                /* arg = */ (void *)0, "connectivity");
+  int status =
+      plugin_thread_create(&connectivity_dequeue_thread_id,
+                           /* attr = */ NULL, connectivity_dequeue_thread,
+                           /* arg = */ (void *)0, "connectivity");
   if (status != 0) {
     connectivity_dequeue_thread_loop = 0;
     ERROR("connectivity plugin: Starting dequeue thread failed.");
-    pthread_mutex_unlock(&connectivity_lock);
-    return (-1);
+    pthread_mutex_unlock(&connectivity_threads_lock);
+    return -1;
   }
 
-  pthread_mutex_unlock(&connectivity_lock);
+  pthread_mutex_unlock(&connectivity_threads_lock);
 
   return status;
 } /* }}} int start_dequeue_thread */
 
 static int start_threads(void) /* {{{ */
 {
-  int status, status2;
-
-  status = start_netlink_thread();
-  status2 = start_dequeue_thread();
+  int status = start_netlink_thread();
+  int status2 = start_dequeue_thread();
 
-  if (status < 0)
+  if (status != 0)
     return status;
   else
     return status2;
@@ -832,28 +807,36 @@ static int start_threads(void) /* {{{ */
 
 static int stop_netlink_thread(int shutdown) /* {{{ */
 {
-  int status;
+  int socket_status;
 
   if (nl_sock != -1) {
-    status = close(nl_sock);
-    if (status != 0) {
+    socket_status = close(nl_sock);
+    if (socket_status != 0) {
       ERROR("connectivity plugin: failed to close socket %d: %d (%s)", nl_sock,
-            status, strerror(errno));
-      return (-1);
-    } else
-      nl_sock = -1;
-  }
+            socket_status, STRERRNO);
+    }
 
-  pthread_mutex_lock(&connectivity_lock);
+    nl_sock = -1;
+  } else
+    socket_status = 0;
+
+  pthread_mutex_lock(&connectivity_threads_lock);
 
   if (connectivity_netlink_thread_loop == 0) {
-    pthread_mutex_unlock(&connectivity_lock);
-    return (-1);
+    pthread_mutex_unlock(&connectivity_threads_lock);
+    // Thread has already been terminated, nothing more to attempt
+    return socket_status;
   }
 
+  // Set thread termination status
   connectivity_netlink_thread_loop = 0;
+  pthread_mutex_unlock(&connectivity_threads_lock);
+
+  // Let threads waiting on access to the interface list know to move
+  // on such that they'll see the thread's termination status
   pthread_cond_broadcast(&connectivity_cond);
-  pthread_mutex_unlock(&connectivity_lock);
+
+  int thread_status;
 
   if (shutdown == 1) {
     // Since the thread is blocking, calling pthread_join
@@ -869,90 +852,85 @@ static int stop_netlink_thread(int shutdown) /* {{{ */
 
     DEBUG("connectivity plugin: Canceling netlink thread for process shutdown");
 
-    status = pthread_cancel(connectivity_netlink_thread_id);
+    thread_status = pthread_cancel(connectivity_netlink_thread_id);
 
-    if (status != 0 && status != ESRCH) {
-      ERROR("connectivity plugin: Unable to cancel netlink thread: %d", status);
-      status = -1;
+    if (thread_status != 0 && thread_status != ESRCH) {
+      ERROR("connectivity plugin: Unable to cancel netlink thread: %d",
+            thread_status);
+      thread_status = -1;
     } else
-      status = 0;
+      thread_status = 0;
   } else {
-    status = pthread_join(connectivity_netlink_thread_id, /* return = */ NULL);
-    if (status != 0 && status != ESRCH) {
-      ERROR("connectivity plugin: Stopping netlink thread failed.");
-      status = -1;
+    thread_status =
+        pthread_join(connectivity_netlink_thread_id, /* return = */ NULL);
+    if (thread_status != 0 && thread_status != ESRCH) {
+      ERROR("connectivity plugin: Stopping netlink thread failed: %d",
+            thread_status);
+      thread_status = -1;
     } else
-      return 0;
+      thread_status = 0;
   }
 
-  pthread_mutex_lock(&connectivity_lock);
+  pthread_mutex_lock(&connectivity_threads_lock);
   memset(&connectivity_netlink_thread_id, 0,
          sizeof(connectivity_netlink_thread_id));
   connectivity_netlink_thread_error = 0;
-  pthread_mutex_unlock(&connectivity_lock);
+  pthread_mutex_unlock(&connectivity_threads_lock);
 
   DEBUG("connectivity plugin: Finished requesting stop of netlink thread");
 
-  return status;
+  if (socket_status != 0)
+    return socket_status;
+  else
+    return thread_status;
 }
 
-static int stop_dequeue_thread(int shutdown) /* {{{ */
+static int stop_dequeue_thread() /* {{{ */
 {
-  int status;
-
-  pthread_mutex_lock(&connectivity_lock);
+  pthread_mutex_lock(&connectivity_threads_lock);
 
   if (connectivity_dequeue_thread_loop == 0) {
-    pthread_mutex_unlock(&connectivity_lock);
-    return (-1);
+    pthread_mutex_unlock(&connectivity_threads_lock);
+    return -1;
   }
 
+  // Set thread termination status
   connectivity_dequeue_thread_loop = 0;
+  pthread_mutex_unlock(&connectivity_threads_lock);
+
+  // Let threads waiting on access to the interface list know to move
+  // on such that they'll see the threads termination status
   pthread_cond_broadcast(&connectivity_cond);
-  pthread_mutex_unlock(&connectivity_lock);
 
-  if (shutdown == 1) {
-    // Calling pthread_cancel here in
-    // the case of a shutdown just assures that the thread is
-    // gone and that the process has been fully terminated.
+  // Calling pthread_cancel here just assures that the thread is
+  // gone and that the process has been fully terminated.
 
-    DEBUG("connectivity plugin: Canceling dequeue thread for process shutdown");
+  DEBUG("connectivity plugin: Canceling dequeue thread for process shutdown");
 
-    status = pthread_cancel(connectivity_dequeue_thread_id);
+  int status = pthread_cancel(connectivity_dequeue_thread_id);
 
-    if (status != 0 && status != ESRCH) {
-      ERROR("connectivity plugin: Unable to cancel dequeue thread: %d", status);
-      status = -1;
-    } else
-      status = 0;
-  } else {
-    status = pthread_join(connectivity_dequeue_thread_id, /* return = */ NULL);
-    if (status != 0 && status != ESRCH) {
-      ERROR("connectivity plugin: Stopping dequeue thread failed.");
-      status = -1;
-    } else
-      status = 0;
-  }
+  if (status != 0 && status != ESRCH) {
+    ERROR("connectivity plugin: Unable to cancel dequeue thread: %d", status);
+    status = -1;
+  } else
+    status = 0;
 
-  pthread_mutex_lock(&connectivity_lock);
+  pthread_mutex_lock(&connectivity_threads_lock);
   memset(&connectivity_dequeue_thread_id, 0,
          sizeof(connectivity_dequeue_thread_id));
-  connectivity_dequeue_thread_error = 0;
-  pthread_mutex_unlock(&connectivity_lock);
+  pthread_mutex_unlock(&connectivity_threads_lock);
 
   DEBUG("connectivity plugin: Finished requesting stop of dequeue thread");
 
-  return (status);
+  return status;
 } /* }}} int stop_dequeue_thread */
 
-static int stop_threads(int shutdown) /* {{{ */
+static int stop_threads() /* {{{ */
 {
-  int status, status2;
-
-  status = stop_netlink_thread(shutdown);
-  status2 = stop_dequeue_thread(shutdown);
+  int status = stop_netlink_thread(1);
+  int status2 = stop_dequeue_thread();
 
-  if (status < 0)
+  if (status != 0)
     return status;
   else
     return status2;
@@ -965,13 +943,16 @@ static int connectivity_init(void) /* {{{ */
            "be monitored");
   }
 
-  return (start_threads());
+  return start_threads();
 } /* }}} int connectivity_init */
 
 static int connectivity_config(const char *key, const char *value) /* {{{ */
 {
   if (ignorelist == NULL) {
     ignorelist = ignorelist_create(/* invert = */ 1);
+
+    if (ignorelist == NULL)
+      return -1;
   }
 
   if (strcasecmp(key, "Interface") == 0) {
@@ -983,66 +964,19 @@ static int connectivity_config(const char *key, const char *value) /* {{{ */
       invert = 0;
     ignorelist_set_invert(ignorelist, invert);
   } else {
-    return (-1);
+    return -1;
   }
 
-  return (0);
+  return 0;
 } /* }}} int connectivity_config */
 
-static void
-connectivity_dispatch_notification(const char *interface, const char *type,
-                                   gauge_t value, gauge_t old_value,
-                                   long long unsigned int timestamp) {
-  char *buf = NULL;
-  notification_t n = {
-      NOTIF_FAILURE, cdtime(), "", "", "connectivity", "", "", "", NULL};
-
-  if (value == LINK_STATE_UP)
-    n.severity = NOTIF_OKAY;
-
-  sstrncpy(n.host, hostname_g, sizeof(n.host));
-  sstrncpy(n.plugin_instance, interface, sizeof(n.plugin_instance));
-  sstrncpy(n.type, "gauge", sizeof(n.type));
-  sstrncpy(n.type_instance, "interface_status", sizeof(n.type_instance));
-
-  gen_message_payload(value, old_value, interface, timestamp, &buf);
-
-  notification_meta_t *m = calloc(1, sizeof(*m));
-
-  if (m == NULL) {
-    char errbuf[1024];
-    sfree(buf);
-    ERROR("connectivity plugin: unable to allocate metadata: %s",
-          sstrerror(errno, errbuf, sizeof(errbuf)));
-    return;
-  }
-
-  sstrncpy(m->name, "ves", sizeof(m->name));
-  m->nm_value.nm_string = sstrdup(buf);
-  m->type = NM_TYPE_STRING;
-  n.meta = m;
-
-  DEBUG("connectivity plugin: notification message: %s",
-        n.meta->nm_value.nm_string);
-
-  DEBUG("connectivity plugin: dispatching state %d for interface %s",
-        (int)value, interface);
-
-  plugin_dispatch_notification(&n);
-  plugin_notification_meta_free(n.meta);
-
-  // malloc'd in gen_message_payload
-  if (buf != NULL)
-    sfree(buf);
-}
-
 static int connectivity_read(void) /* {{{ */
 {
-  pthread_mutex_lock(&connectivity_lock);
+  pthread_mutex_lock(&connectivity_threads_lock);
 
   if (connectivity_netlink_thread_error != 0) {
 
-    pthread_mutex_unlock(&connectivity_lock);
+    pthread_mutex_unlock(&connectivity_threads_lock);
 
     ERROR("connectivity plugin: The netlink thread had a problem. Restarting "
           "it.");
@@ -1058,37 +992,21 @@ static int connectivity_read(void) /* {{{ */
 
     start_netlink_thread();
 
-    return (-1);
+    return -1;
   } /* if (connectivity_netlink_thread_error != 0) */
 
-  if (connectivity_dequeue_thread_error != 0) {
+  pthread_mutex_unlock(&connectivity_threads_lock);
 
-    pthread_mutex_unlock(&connectivity_lock);
-
-    ERROR("connectivity plugin: The dequeue thread had a problem. Restarting "
-          "it.");
-
-    stop_dequeue_thread(0);
-
-    start_dequeue_thread();
-
-    return (-1);
-  } /* if (connectivity_dequeue_thread_error != 0) */
-
-  pthread_mutex_unlock(&connectivity_lock);
-
-  return (0);
+  return 0;
 } /* }}} int connectivity_read */
 
 static int connectivity_shutdown(void) /* {{{ */
 {
-  interface_list_t *il;
-
   DEBUG("connectivity plugin: Shutting down thread.");
-  if (stop_threads(1) < 0)
-    return (-1);
 
-  il = interface_list_head;
+  int status = stop_threads();
+
+  interface_list_t *il = interface_list_head;
   while (il != NULL) {
     interface_list_t *il_next;
 
@@ -1102,7 +1020,7 @@ static int connectivity_shutdown(void) /* {{{ */
 
   ignorelist_free(ignorelist);
 
-  return (0);
+  return status;
 } /* }}} int connectivity_shutdown */
 
 void module_register(void) {