added support for filtering of interfaces. filter or exclusion list needs to be be written to exclude

file located in linstatus directory. watchlink accepts sigusr1 to reload filter without requiring
restart on configuration change.

3 files changed, 73 insertions, 4 deletions

diff --git a/watchlink/netlink_listener.cc b/watchlink/netlink_listener.cc
index 6c9fcc51..a13be216 100644
--- a/watchlink/netlink_listener.cc
+++ b/watchlink/netlink_listener.cc
@@ -134,6 +134,21 @@ NetlinkListener::init()
  *
  **/
 bool
+NetlinkListener::process(NetlinkEvent &e, set<string> filter)
+{
+  bool state = process(e);
+  if (state == true && filter.find(e.get_iface()) != filter.end()) {
+    e = NetlinkEvent();
+    state = false;
+  }
+  return state;
+}
+
+/**
+ *
+ *
+ **/
+bool
 NetlinkListener::process(NetlinkEvent &e)
 {
   if (_fd <= 0) {
diff --git a/watchlink/netlink_listener.hh b/watchlink/netlink_listener.hh
index 5b5a3ca7..b73130fd 100644
--- a/watchlink/netlink_listener.hh
+++ b/watchlink/netlink_listener.hh
@@ -29,6 +29,7 @@
 #define __NETLINK_LISTENER_HH__
 
 #include "netlink_event.hh"
+#include <set>
 #include <string>
 
 class NetlinkListener
@@ -46,6 +47,9 @@ public: //methods
   bool
   process(NetlinkEvent &e);
 
+  bool
+  process(NetlinkEvent &e, std::set<std::string> filter);
+
   int
   get_sock() {return _fd;}
 
diff --git a/watchlink/watchlink.cc b/watchlink/watchlink.cc
index aee53d09..8d2f0239 100644
--- a/watchlink/watchlink.cc
+++ b/watchlink/watchlink.cc
@@ -29,13 +29,16 @@
 #include <iostream>
 #include <stdio.h>
 #include <string>
+#include <set>
 #include <fcntl.h>
 #include <syslog.h>
 #include <errno.h>
 
 #include <linux/types.h>
 #include <sys/socket.h>
+#include <signal.h>
 #include <linux/rtnetlink.h>
+#include "rl_str_proc.hh"
 #include "netlink_send.hh"
 #include "netlink_listener.hh"
 #include "netlink_linkstatus.hh"
@@ -52,6 +55,8 @@ struct option longopts[] =
   { 0 }
 };
 
+set<string> g_exclude;
+string g_link_dir = "/var/linkstatus";
 
 /**
  *
@@ -73,11 +78,52 @@ usage()
  *
  *
  **/
+set<string> 
+load_exclusion_file(const string &link_dir)
+{
+  set<string> coll;
+
+  string file = link_dir + "/exclude";
+  FILE *fp = fopen(file.c_str(), "r");
+  if (fp == NULL) {
+    syslog(LOG_ERR,"load_exclusion_file(), failed to open state file");
+    cerr << "load_exclusion_file(), failed to open state file" << endl;
+    return coll; //means we are still up, ignore...
+  }
+
+  char str[1025];
+  while (fgets(str, 1024, fp)) {
+    string line(str);
+
+    StrProc tokens(line, ",");
+    for (int i = 0; i < tokens.size(); ++i) {
+      coll.insert(tokens.get(i));
+    }
+  }
+  fclose(fp);
+  return coll;
+}
+
+/**
+ *
+ *
+ **/
+static void 
+sig_user(int signo)
+{
+  //reload interface exclusion list
+  g_exclude = load_exclusion_file(g_link_dir);
+}
+
+
+/**
+ *
+ *
+ **/
 int 
 main(int argc, char* const argv[])
 {
   int ch;
-  string link_dir = "/var/linkstatus";
   bool send_request = false;
   bool debug = false;
   bool daemon = false;
@@ -94,7 +140,7 @@ main(int argc, char* const argv[])
       send_request = true;
       break;
     case 'l':
-      link_dir = optarg;
+      g_link_dir = optarg;
       break;
     case 'i':
       pid_path = optarg;
@@ -129,6 +175,10 @@ main(int argc, char* const argv[])
     pid_output(pid_path.c_str());
   }
 
+  //load interface exclusion list
+  g_exclude = load_exclusion_file(g_link_dir);
+
+  signal(SIGUSR1, sig_user);
 
   int sock = nl_listener.init();
   if (sock <= 0) {
@@ -149,13 +199,13 @@ main(int argc, char* const argv[])
     }
   }
 
-  NetlinkLinkStatus nl_ls(sock, link_dir, debug);
+  NetlinkLinkStatus nl_ls(sock, g_link_dir, debug);
 
   while (true) {
     //    cout << "watchlink: now entering listening mode: " << endl;
 
     NetlinkEvent nl_event;
-    if (nl_listener.process(nl_event) == true) {
+    if (nl_listener.process(nl_event, g_exclude) == true) {
       if (send_request) {
 	if (nl_send.send_get(sock, RTM_GETADDR) != 0) {
 	  syslog(LOG_ERR,"watchlink(), error sending. exiting..");