Added support for PING_OPT_DEVICE.

This option may be used to set the outgoing network device to be used. The
value passed must be a char-pointer to a null-terminated string specifying an
interface name (e.g. eth0).

Please note that this might not be supported by all operating systems. In that
case, ping_setopt() sets the error to "operation not supported".

diff --git a/src/liboping.c b/src/liboping.c
index b21188b..acbc715 100644 (file)
--- a/src/liboping.c
+++ b/src/liboping.c
@@ -134,6 +134,8 @@ struct pingobj
        struct sockaddr         *srcaddr;
        socklen_t                srcaddrlen;
 
+       char                    *device;
+
        char                     errmsg[PING_ERRMSG_LEN];
 
        pinghost_t              *head;
@@ -1045,6 +1047,9 @@ void ping_destroy (pingobj_t *obj)
        if (obj->srcaddr != NULL)
                free (obj->srcaddr);
 
+       if (obj->device != NULL)
+               free (obj->device);
+
        free (obj);
 
        return;
@@ -1167,6 +1172,28 @@ int ping_setopt (pingobj_t *obj, int option, void *value)
                } /* case PING_OPT_SOURCE */
                break;
 
+               case PING_OPT_DEVICE:
+               {
+#ifdef SO_BINDTODEVICE
+                       char *device = strdup ((char *) value);
+
+                       if (device == NULL)
+                       {
+                               ping_set_errno (obj, errno);
+                               ret = -1;
+                               break;
+                       }
+
+                       if (obj->device != NULL)
+                               free (obj->device);
+                       obj->device = device;
+#else /* ! SO_BINDTODEVICE */
+                       ping_set_errno (obj, ENOTSUP);
+                       ret = -1;
+#endif /* ! SO_BINDTODEVICE */
+               } /* case PING_OPT_DEVICE */
+               break;
+
                default:
                        ret = -2;
        } /* switch (option) */
@@ -1334,6 +1361,25 @@ int ping_host_add (pingobj_t *obj, const char *host)
                        }
                }
 
+#ifdef SO_BINDTODEVICE
+               if (obj->device != NULL)
+               {
+                       if (setsockopt (ph->fd, SOL_SOCKET, SO_BINDTODEVICE,
+                                       obj->device, strlen (obj->device) + 1) != 0)
+                       {
+#if WITH_DEBUG
+                               char errbuf[PING_ERRMSG_LEN];
+                               dprintf ("setsockopt: %s\n",
+                                               sstrerror (errno, errbuf, sizeof (errbuf)));
+#endif
+                               ping_set_errno (obj, errno);
+                               close (ph->fd);
+                               ph->fd = -1;
+                               continue;
+                       }
+               }
+#endif /* SO_BINDTODEVICE */
+
                assert (sizeof (struct sockaddr_storage) >= ai_ptr->ai_addrlen);
                memset (ph->addr, '\0', sizeof (struct sockaddr_storage));
                memcpy (ph->addr, ai_ptr->ai_addr, ai_ptr->ai_addrlen);

diff --git a/src/mans/ping_setopt.pod b/src/mans/ping_setopt.pod
index 2452701..ad85979 100644 (file)
--- a/src/mans/ping_setopt.pod
+++ b/src/mans/ping_setopt.pod
@@ -53,10 +53,19 @@ L<ping(1)> command.
 =item B<PING_OPT_SOURCE>
 
 Set the source address to use. The value passed must be a char-pointer to a
-null-terminated string. This option will ignore the address family setting (as
+null-terminated string specifying either a numerical network address or
+network hostname. This option will ignore the address family setting (as
 set with B<PING_OPT_AF>) and will set the object's address family according to
 the source address assigned.
 
+=item B<PING_OPT_DEVICE>
+
+Set the outgoing network device to be used. The value passed must be a
+char-pointer to a null-terminated string specifying an interface name
+(e.E<nbsp>g. C<eth0>). Please note that this might not be supported by all
+operating systems. In that case, B<ping_setopt> sets the error to C<operation
+not supported>.
+
 =back
 
 The I<val> argument is a pointer to the new value. It must not be NULL. It is

diff --git a/src/oping.h b/src/oping.h
index 0debadf..2ffdf1f 100644 (file)
--- a/src/oping.h
+++ b/src/oping.h
@@ -59,6 +59,7 @@ typedef struct pingobj pingobj_t;
 #define PING_OPT_AF      0x04
 #define PING_OPT_DATA    0x08
 #define PING_OPT_SOURCE  0x10
+#define PING_OPT_DEVICE  0x20
 
 #define PING_DEF_TIMEOUT 1.0
 #define PING_DEF_TTL     255