X-Git-Url: https://unix4lyfe.org/gitweb/darkstat-debian/blobdiff_plain/4da209d9116b41ab59eeedc5823bc2cb64b5bc3e..HEAD:/cap.c

diff --git a/cap.c b/cap.c
index 7e1c41b..e5f3a3e 100644
--- a/cap.c
+++ b/cap.c
@@ -1,5 +1,5 @@
 /* darkstat 3
- * copyright (c) 2001-2011 Emil Mikulic.
+ * copyright (c) 2001-2014 Emil Mikulic.
  *
  * cap.c: capture packets, and hand them off to decode and acct.
  *
@@ -112,6 +112,7 @@ static void cap_set_filter(pcap_t *pcap, const char *filter) {
    free(tmp_filter);
 }
 
+/* Start capturing on just one interface. Called from cap_start(). */
 static void cap_start_one(struct cap_iface *iface, const int promisc) {
    char errbuf[PCAP_ERRBUF_SIZE], *tmp_device;
    int linktype, snaplen, waited;
@@ -395,15 +396,26 @@ static void callback(u_char *user,
       acct_for(&sm, &iface->local_ips);
 }
 
-/* Process any packets currently in the capture buffer. */
-void cap_poll(fd_set *read_set _unused_on_linux_) {
+/* Process any packets currently in the capture buffer.
+ * Returns 0 on error (usually means the interface went down).
+ */
+int cap_poll(fd_set *read_set _unused_on_linux_) {
    struct cap_iface *iface;
+   static int told = 0;
 
    STAILQ_FOREACH(iface, &cap_ifs, entries) {
       /* Once per capture poll, check our IP address.  It's used in accounting
        * for traffic graphs.
        */
       localip_update(iface->name, &iface->local_ips);
+      if (!told && iface->local_ips.num_addrs == 0) {
+         verbosef("interface '%s' has no addresses, "
+                  "your graphs will be blank",
+                  iface->name);
+         verbosef("please read the darkstat manpage, "
+                  "and consider using the -l option");
+         told = 1;
+      }
 
       for (;;) {
          struct timespec t;
@@ -415,18 +427,19 @@ void cap_poll(fd_set *read_set _unused_on_linux_) {
                -1, /* count = entire buffer */
                callback,
                (u_char*)iface); /* user = struct to pass to callback */
+         timer_stop(&t,
+                    2 * CAP_TIMEOUT_MSEC * 1000000,
+                    "pcap_dispatch took too long");
 
          if (ret < 0) {
             warnx("pcap_dispatch('%s'): %s",
                iface->name, pcap_geterr(iface->pcap));
-            continue;
+            return 0;
          }
-         timer_stop(&t,
-                    2 * CAP_TIMEOUT_MSEC * 1000000,
-                    "pcap_dispatch took too long");
 
-         if (0) /* debugging */
-            verbosef("iface '%s' got %d pkts", iface->name, ret);
+#if 0 /* debugging */
+         verbosef("iface '%s' got %d pkts", iface->name, ret);
+#endif
 
 #ifdef linux
          /* keep looping until we've dispatched all the outstanding packets */
@@ -439,6 +452,7 @@ void cap_poll(fd_set *read_set _unused_on_linux_) {
       }
    }
    cap_stats_update();
+   return 1;
 }
 
 void cap_stop(void) {
@@ -454,6 +468,23 @@ void cap_stop(void) {
    title_interfaces = NULL;
 }
 
+/* This is only needed by the DNS child. In the main process, the deallocation
+ * happens in cap_start().
+ */
+void cap_free_args(void) {
+   while (!STAILQ_EMPTY(&cli_ifnames)) {
+      struct strnode *ifname = STAILQ_FIRST(&cli_ifnames);
+      STAILQ_REMOVE_HEAD(&cli_ifnames, entries);
+      free(ifname);
+   }
+
+   while (!STAILQ_EMPTY(&cli_filters)) {
+      struct strnode *filter = STAILQ_FIRST(&cli_filters);
+      STAILQ_REMOVE_HEAD(&cli_filters, entries);
+      free(filter);
+   }
+}
+
 /* Run through entire capfile. */
 void cap_from_file(const char *capfile) {
    char errbuf[PCAP_ERRBUF_SIZE];