Add more interface flags to pcap_findalldevs().

[libpcap] / pcap.c

diff --git a/pcap.c b/pcap.c
index 64d64ed75d455fb23880153e8d33a6e227b9ffbe..b2c2790968c8b74d6a673f56f3bfddd618b9160f 100644 (file)
--- a/pcap.c
+++ b/pcap.c
@@ -567,8 +567,28 @@ get_figure_of_merit(pcap_if_t *dev)
                n |= 0x80000000;
        if (!(dev->flags & PCAP_IF_UP))
                n |= 0x40000000;
-       if (dev->flags & PCAP_IF_LOOPBACK)
+
+       /*
+        * Give non-wireless interfaces that aren't disconnected a better
+        * figure of merit than interfaces that are disconnected, as
+        * "disconnected" should indicate that the interface isn't
+        * plugged into a network and thus won't give you any traffic.
+        *
+        * For wireless interfaces, it means "associated with a network",
+        * which we presume not to necessarily prevent capture, as you
+        * might run the adapter in some flavor of monitor mode.
+        */
+       if (!(dev->flags & PCAP_IF_WIRELESS) &&
+           (dev->flags & PCAP_IF_CONNECTION_STATUS) == PCAP_IF_CONNECTION_STATUS_DISCONNECTED)
                n |= 0x20000000;
+
+       /*
+        * Sort loopback devices after non-loopback devices, *except* for
+        * disconnected devices.
+        */
+       if (dev->flags & PCAP_IF_LOOPBACK)
+               n |= 0x10000000;
+
        return (n);
 }
 
@@ -992,7 +1012,21 @@ find_or_add_dev(pcap_if_list_t *devlistp, const char *name, bpf_u_int32 flags,
        }
 
        /*
-        * No, we didn't find it.  Try to add it to the list of devices.
+        * No, we didn't find it.
+        */
+
+       /*
+        * Try to get additional flags for the device.
+        */
+       if (get_if_flags(name, &flags, errbuf) == -1) {
+               /*
+                * Failed.
+                */
+               return (NULL);
+       }
+
+       /*
+        * Now, try to add it to the list of devices.
         */
        return (add_dev(devlistp, name, flags, description, errbuf));
 }
@@ -3278,6 +3312,9 @@ pcap_statustostr(int errnum)
 
        case PCAP_ERROR_TSTAMP_PRECISION_NOTSUP:
                return ("That device doesn't support that time stamp precision");
+
+       case PCAP_ERROR_OPERATION_NOTSUP:
+               return ("That device doesn't support that operation");
        }
        (void)pcap_snprintf(ebuf, sizeof ebuf, "Unknown error: %d", errnum);
        return(ebuf);