Have a pcap_if_list_t structure for use by the findalldevs code.

It's not part of the API, but it's an internal structure used by the
findalldevs code.  Currently, it just has a pointer to the beginning of
the list, but it could change in order to speed up the process of adding
to the list.

33 files changed, 143 insertions, 179 deletions

diff --git a/fad-getad.c b/fad-getad.c
index b67b5cdc..a4625dfd 100644
--- a/fad-getad.c
+++ b/fad-getad.c
@@ -144,10 +144,9 @@ get_sa_len(struct sockaddr *addr)
  * could be opened.
  */
 int
-pcap_findalldevs_interfaces(pcap_if_t **alldevsp, char *errbuf,
+pcap_findalldevs_interfaces(pcap_if_list_t *devlistp, char *errbuf,
     int (*check_usable)(const char *))
 {
-	pcap_if_t *devlist = NULL;
 	struct ifaddrs *ifap, *ifa;
 	struct sockaddr *addr, *netmask, *broadaddr, *dstaddr;
 	size_t addr_size, broadaddr_size, dstaddr_size;
@@ -265,7 +264,7 @@ pcap_findalldevs_interfaces(pcap_if_t **alldevsp, char *errbuf,
 		/*
 		 * Add information for this address to the list.
 		 */
-		if (add_addr_to_iflist(&devlist, ifa->ifa_name,
+		if (add_addr_to_iflist(devlistp, ifa->ifa_name,
 		    if_flags_to_pcap_flags(ifa->ifa_name, ifa->ifa_flags),
 		    addr, addr_size, netmask, addr_size,
 		    broadaddr, broadaddr_size, dstaddr, dstaddr_size,
@@ -277,16 +276,5 @@ pcap_findalldevs_interfaces(pcap_if_t **alldevsp, char *errbuf,
 
 	freeifaddrs(ifap);
 
-	if (ret == -1) {
-		/*
-		 * We had an error; free the list we've been constructing.
-		 */
-		if (devlist != NULL) {
-			pcap_freealldevs(devlist);
-			devlist = NULL;
-		}
-	}
-
-	*alldevsp = devlist;
 	return (ret);
 }
diff --git a/fad-gifc.c b/fad-gifc.c
index 1b24af29..d431ba16 100644
--- a/fad-gifc.c
+++ b/fad-gifc.c
@@ -132,10 +132,9 @@ struct rtentry;		/* declarations in <net/if.h> */
  * we already have that.
  */
 int
-pcap_findalldevs_interfaces(pcap_if_t **alldevsp, char *errbuf,
+pcap_findalldevs_interfaces(pcap_if_list_t *devlistp, char *errbuf,
     int (*check_usable)(const char *))
 {
-	pcap_if_t *devlist = NULL;
 	register int fd;
 	register struct ifreq *ifrp, *ifend, *ifnext;
 	size_t n;
@@ -401,7 +400,7 @@ pcap_findalldevs_interfaces(pcap_if_t **alldevsp, char *errbuf,
 		/*
 		 * Add information for this address to the list.
 		 */
-		if (add_addr_to_iflist(&devlist, ifrp->ifr_name,
+		if (add_addr_to_iflist(devlistp, ifrp->ifr_name,
 		    if_flags_to_pcap_flags(ifrp->ifr_name, ifrflags.ifr_flags),
 		    &ifrp->ifr_addr, SA_LEN(&ifrp->ifr_addr),
 		    netmask, netmask_size, broadaddr, broadaddr_size,
@@ -413,16 +412,5 @@ pcap_findalldevs_interfaces(pcap_if_t **alldevsp, char *errbuf,
 	free(buf);
 	(void)close(fd);
 
-	if (ret == -1) {
-		/*
-		 * We had an error; free the list we've been constructing.
-		 */
-		if (devlist != NULL) {
-			pcap_freealldevs(devlist);
-			devlist = NULL;
-		}
-	}
-
-	*alldevsp = devlist;
 	return (ret);
 }
diff --git a/fad-glifc.c b/fad-glifc.c
index 511481cf..e53bad76 100644
--- a/fad-glifc.c
+++ b/fad-glifc.c
@@ -75,10 +75,9 @@ struct rtentry;		/* declarations in <net/if.h> */
  * SIOCGLIFCONF rather than SIOCGIFCONF in order to get IPv6 addresses.)
  */
 int
-pcap_findalldevs_interfaces(pcap_if_t **alldevsp, char *errbuf,
+pcap_findalldevs_interfaces(pcap_if_list_t *devlistp, char *errbuf,
     int (*check_usable)(const char *))
 {
-	pcap_if_t *devlist = NULL;
 	register int fd4, fd6, fd;
 	register struct lifreq *ifrp, *ifend;
 	struct lifnum ifn;
@@ -329,7 +328,7 @@ pcap_findalldevs_interfaces(pcap_if_t **alldevsp, char *errbuf,
 		/*
 		 * Add information for this address to the list.
 		 */
-		if (add_addr_to_iflist(&devlist, ifrp->lifr_name,
+		if (add_addr_to_iflist(devlistp, ifrp->lifr_name,
 		    if_flags_to_pcap_flags(ifrp->lifr_name, ifrflags.lifr_flags),
 		    (struct sockaddr *)&ifrp->lifr_addr,
 		    sizeof (struct sockaddr_storage),
@@ -344,16 +343,5 @@ pcap_findalldevs_interfaces(pcap_if_t **alldevsp, char *errbuf,
 	(void)close(fd6);
 	(void)close(fd4);
 
-	if (ret == -1) {
-		/*
-		 * We had an error; free the list we've been constructing.
-		 */
-		if (devlist != NULL) {
-			pcap_freealldevs(devlist);
-			devlist = NULL;
-		}
-	}
-
-	*alldevsp = devlist;
 	return (ret);
 }
diff --git a/pcap-bpf.c b/pcap-bpf.c
index 60086e42..d4f55238 100644
--- a/pcap-bpf.c
+++ b/pcap-bpf.c
@@ -2622,7 +2622,7 @@ check_bpf_bindable(const char *name)
 
 #if defined(__FreeBSD__) && defined(SIOCIFCREATE2)
 static int
-finddevs_usb(pcap_if_t **alldevsp, char *errbuf)
+finddevs_usb(pcap_if_list_t *devlistp, char *errbuf)
 {
 	DIR *usbdir;
 	struct dirent *usbitem;
@@ -2684,7 +2684,7 @@ finddevs_usb(pcap_if_t **alldevsp, char *errbuf)
 		 * so we need to avoid adding multiple capture devices
 		 * for each bus.
 		 */
-		if (find_or_add_dev(alldevsp, name, PCAP_IF_UP, NULL, errbuf) == NULL) {
+		if (find_or_add_dev(devlistp, name, PCAP_IF_UP, NULL, errbuf) == NULL) {
 			free(name);
 			closedir(usbdir);
 			return (PCAP_ERROR);
@@ -2697,16 +2697,16 @@ finddevs_usb(pcap_if_t **alldevsp, char *errbuf)
 #endif
 
 int
-pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
+pcap_platform_finddevs(pcap_if_list_t *devlistp, char *errbuf)
 {
 	/*
 	 * Get the list of regular interfaces first.
 	 */
-	if (pcap_findalldevs_interfaces(alldevsp, errbuf, check_bpf_bindable) == -1)
+	if (pcap_findalldevs_interfaces(devlistp, errbuf, check_bpf_bindable) == -1)
 		return (-1);	/* failure */
 
 #if defined(__FreeBSD__) && defined(SIOCIFCREATE2)
-	if (finddevs_usb(alldevsp, errbuf) == -1)
+	if (finddevs_usb(devlistp, errbuf) == -1)
 		return (-1);
 #endif
 
diff --git a/pcap-bt-linux.c b/pcap-bt-linux.c
index 2a36e264..8a258ebf 100644
--- a/pcap-bt-linux.c
+++ b/pcap-bt-linux.c
@@ -74,7 +74,7 @@ struct pcap_bt {
 };
 
 int
-bt_findalldevs(pcap_if_t **alldevsp, char *err_str)
+bt_findalldevs(pcap_if_list_t *devlistp, char *err_str)
 {
 	struct hci_dev_list_req *dev_list;
 	struct hci_dev_req *dev_req;
@@ -119,7 +119,7 @@ bt_findalldevs(pcap_if_t **alldevsp, char *err_str)
 		pcap_snprintf(dev_name, 20, BT_IFACE"%d", dev_req->dev_id);
 		pcap_snprintf(dev_descr, 30, "Bluetooth adapter number %d", i);
 
-		if (add_dev(alldevsp, dev_name, 0, dev_descr, err_str) == NULL)
+		if (add_dev(devlistp, dev_name, 0, dev_descr, err_str) == NULL)
 		{
 			ret = -1;
 			break;
diff --git a/pcap-bt-linux.h b/pcap-bt-linux.h
index e098654d..163bd341 100644
--- a/pcap-bt-linux.h
+++ b/pcap-bt-linux.h
@@ -34,5 +34,5 @@
 /*
  * Prototypes for Bluetooth-related functions
  */
-int bt_findalldevs(pcap_if_t **alldevsp, char *err_str);
+int bt_findalldevs(pcap_if_list_t *devlistp, char *err_str);
 pcap_t *bt_create(const char *device, char *ebuf, int *is_ours);
diff --git a/pcap-bt-monitor-linux.c b/pcap-bt-monitor-linux.c
index 3cd6178b..63863a9f 100644
--- a/pcap-bt-monitor-linux.c
+++ b/pcap-bt-monitor-linux.c
@@ -60,11 +60,11 @@ struct hci_mon_hdr {
 } __attribute__((packed));
 
 int
-bt_monitor_findalldevs(pcap_if_t **alldevsp, char *err_str)
+bt_monitor_findalldevs(pcap_if_list_t *devlistp, char *err_str)
 {
     int         ret = 0;
 
-    if (add_dev(alldevsp, INTERFACE_NAME, 0,
+    if (add_dev(devlistp, INTERFACE_NAME, 0,
                 "Bluetooth Linux Monitor", err_str) == NULL)
     {
         ret = -1;
diff --git a/pcap-bt-monitor-linux.h b/pcap-bt-monitor-linux.h
index aada2bc7..8133710a 100644
--- a/pcap-bt-monitor-linux.h
+++ b/pcap-bt-monitor-linux.h
@@ -28,5 +28,5 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
-int bt_monitor_findalldevs(pcap_if_t **alldevsp, char *err_str);
+int bt_monitor_findalldevs(pcap_if_list_t *devlistp, char *err_str);
 pcap_t *bt_monitor_create(const char *device, char *ebuf, int *is_ours);
diff --git a/pcap-dag.c b/pcap-dag.c
index ee024dfd..fbd12973 100644
--- a/pcap-dag.c
+++ b/pcap-dag.c
@@ -1068,7 +1068,7 @@ dag_stats(pcap_t *p, struct pcap_stat *ps) {
  * Add all DAG devices.
  */
 int
-dag_findalldevs(pcap_if_t **devlistp, char *errbuf)
+dag_findalldevs(pcap_if_list_t *devlistp, char *errbuf)
 {
 	char name[12];	/* XXX - pick a size */
 	int ret = 0;
@@ -1356,9 +1356,8 @@ dag_get_datalink(pcap_t *p)
  * There are no regular interfaces, just DAG interfaces.
  */
 int
-pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
+pcap_platform_finddevs(pcap_if_list_t *devlistp _U_, char *errbuf)
 {
-	*alldevsp = NULL;
 	return (0);
 }
 
diff --git a/pcap-dag.h b/pcap-dag.h
index dfeccd8b..67361af9 100644
--- a/pcap-dag.h
+++ b/pcap-dag.h
@@ -9,4 +9,4 @@
  */
 
 pcap_t *dag_create(const char *, char *, int *);
-int dag_findalldevs(pcap_if_t **devlistp, char *errbuf);
+int dag_findalldevs(pcap_if_list_t *devlistp, char *errbuf);
diff --git a/pcap-dbus.c b/pcap-dbus.c
index 6408fe51..41f50411 100644
--- a/pcap-dbus.c
+++ b/pcap-dbus.c
@@ -268,11 +268,11 @@ dbus_create(const char *device, char *ebuf, int *is_ours)
 }
 
 int
-dbus_findalldevs(pcap_if_t **alldevsp, char *err_str)
+dbus_findalldevs(pcap_if_list_t *devlistp, char *err_str)
 {
-	if (add_dev(alldevsp, "dbus-system", 0, "D-Bus system bus", err_str) == NULL)
+	if (add_dev(devlistp, "dbus-system", 0, "D-Bus system bus", err_str) == NULL)
 		return -1;
-	if (add_dev(alldevsp, "dbus-session", 0, "D-Bus session bus", err_str) == NULL)
+	if (add_dev(devlistp, "dbus-session", 0, "D-Bus session bus", err_str) == NULL)
 		return -1;
 	return 0;
 }
diff --git a/pcap-dbus.h b/pcap-dbus.h
index 67493cce..c97f2e12 100644
--- a/pcap-dbus.h
+++ b/pcap-dbus.h
@@ -1,2 +1,2 @@
 pcap_t *dbus_create(const char *, char *, int *);
-int dbus_findalldevs(pcap_if_t **devlistp, char *errbuf);
+int dbus_findalldevs(pcap_if_list_t *devlistp, char *errbuf);
diff --git a/pcap-dlpi.c b/pcap-dlpi.c
index 04251dd8..dc243752 100644
--- a/pcap-dlpi.c
+++ b/pcap-dlpi.c
@@ -1026,7 +1026,7 @@ is_dlpi_interface(const char *name)
 }
 
 int
-pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
+pcap_platform_finddevs(pcap_if_list_t *devlistp, char *errbuf)
 {
 #ifdef HAVE_SOLARIS
 	int fd;
@@ -1042,7 +1042,7 @@ pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
 	/*
 	 * Get the list of regular interfaces first.
 	 */
-	if (pcap_findalldevs_interfaces(alldevsp, errbuf, is_dlpi_interface) == -1)
+	if (pcap_findalldevs_interfaces(devlistp, errbuf, is_dlpi_interface) == -1)
 		return (-1);	/* failure */
 
 #ifdef HAVE_SOLARIS
@@ -1068,7 +1068,7 @@ pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
 	}
 	for (i = 0; i < buf.nunits; i++) {
 		pcap_snprintf(baname, sizeof baname, "ba%u", i);
-		if (add_dev(alldevsp, baname, 0, NULL, errbuf) == NULL)
+		if (add_dev(devlistp, baname, 0, NULL, errbuf) == NULL)
 			return (-1);
 	}
 #endif
diff --git a/pcap-dos.c b/pcap-dos.c
index dbbfc78f..20428547 100644
--- a/pcap-dos.c
+++ b/pcap-dos.c
@@ -539,17 +539,17 @@ int pcap_lookupnet (const char *device, bpf_u_int32 *localnet,
 /*
  * Get a list of all interfaces that are present and that we probe okay.
  * Returns -1 on error, 0 otherwise.
- * The list, as returned through "alldevsp", may be NULL if no interfaces
- * were up and could be opened.
+ * The list may be NULL epty if no interfaces were up and could be opened.
  */
-int pcap_platform_finddevs  (pcap_if_t **alldevsp, char *errbuf)
+int pcap_platform_finddevs  (pcap_if_list_t *devlistp, char *errbuf)
 {
   struct device     *dev;
+#if 0   /* Pkt drivers should have no addresses */
   struct sockaddr_in sa_ll_1, sa_ll_2;
   struct sockaddr   *addr, *netmask, *broadaddr, *dstaddr;
-  pcap_if_t *devlist = NULL;
+#endif
   int       ret = 0;
-  size_t    addr_size = sizeof(*addr);
+  int       found = 0;
 
   for (dev = (struct device*)dev_base; dev; dev = dev->next)
   {
@@ -562,6 +562,14 @@ int pcap_platform_finddevs  (pcap_if_t **alldevsp, char *errbuf)
     FLUSHK();
     (*dev->close) (dev);
 
+    if (add_dev(devlistp, dev->name, dev->flags,
+                dev->long_name, errbuf) == NULL)
+    {
+      ret = -1;
+      break;
+    }
+    found = 1;
+#if 0   /* Pkt drivers should have no addresses */
     memset (&sa_ll_1, 0, sizeof(sa_ll_1));
     memset (&sa_ll_2, 0, sizeof(sa_ll_2));
     sa_ll_1.sin_family = AF_INET;
@@ -573,16 +581,10 @@ int pcap_platform_finddevs  (pcap_if_t **alldevsp, char *errbuf)
     broadaddr = (struct sockaddr*) &sa_ll_2;
     memset (&sa_ll_2.sin_addr, 0xFF, sizeof(sa_ll_2.sin_addr));
 
-    if (add_dev(&devlist, dev->name, dev->flags,
-                dev->long_name, errbuf) == NULL)
-    {
-      ret = -1;
-      break;
-    }
-#if 0   /* Pkt drivers should have no addresses */
-    if (add_addr_to_dev(curdev, addr, addr_size,
-                        netmask, addr_size, broadaddr, addr_size,
-                        dstaddr, addr_size, errbuf) < 0)
+    if (add_addr_to_dev(curdev, addr, sizeof(*addr),
+                        netmask, sizeof(*netmask),
+                        broadaddr, sizeof(*broadaddr),
+                        dstaddr, sizeof(*dstaddr), errbuf) < 0)
     {
       ret = -1;
       break;
@@ -590,16 +592,9 @@ int pcap_platform_finddevs  (pcap_if_t **alldevsp, char *errbuf)
 #endif
   }
 
-  if (devlist && ret < 0)
-  {
-    pcap_freealldevs (devlist);
-    devlist = NULL;
-  }
-  else
-  if (!devlist)
+  if (ret == 0 && !found)
      strcpy (errbuf, "No drivers found");
 
-  *alldevsp = devlist;
   return (ret);
 }
 
diff --git a/pcap-int.h b/pcap-int.h
index 65b7b52d..b5fc8ea3 100644
--- a/pcap-int.h
+++ b/pcap-int.h
@@ -404,6 +404,8 @@ int	pcap_check_activated(pcap_t *);
 /*
  * Internal interfaces for "pcap_findalldevs()".
  *
+ * A pcap_if_list_t * is a reference to a list of devices.
+ *
  * "pcap_platform_finddevs()" is the platform-dependent routine to
  * find local network interfaces.
  *
@@ -417,22 +419,24 @@ int	pcap_check_activated(pcap_t *);
  * "find_or_add_dev()" checks whether a device is already in a pcap_if_list_t
  * and, if not, adds an entry for it.
  */
-int	pcap_platform_finddevs(pcap_if_t **, char *);
+struct pcap_if_list;
+typedef struct pcap_if_list pcap_if_list_t;
+int	pcap_platform_finddevs(pcap_if_list_t *, char *);
 #if !defined(_WIN32) && !defined(MSDOS)
-int	pcap_findalldevs_interfaces(pcap_if_t **, char *,
+int	pcap_findalldevs_interfaces(pcap_if_list_t *, char *,
 	    int (*)(const char *));
 #endif
-pcap_if_t *find_or_add_dev(pcap_if_t **, const char *, bpf_u_int32,
+pcap_if_t *find_or_add_dev(pcap_if_list_t *, const char *, bpf_u_int32,
 	    const char *, char *);
-pcap_if_t *find_dev(pcap_if_t **, const char *);
-pcap_if_t *add_dev(pcap_if_t **, const char *, bpf_u_int32, const char *,
+pcap_if_t *find_dev(pcap_if_list_t *, const char *);
+pcap_if_t *add_dev(pcap_if_list_t *, const char *, bpf_u_int32, const char *,
 	    char *);
 int	add_addr_to_dev(pcap_if_t *, struct sockaddr *, size_t,
 	    struct sockaddr *, size_t, struct sockaddr *, size_t,
 	    struct sockaddr *dstaddr, size_t, char *errbuf);
 #ifndef _WIN32
 bpf_u_int32 if_flags_to_pcap_flags(const char *, u_int);
-int	add_addr_to_iflist(pcap_if_t **, const char *, bpf_u_int32,
+int	add_addr_to_iflist(pcap_if_list_t *, const char *, bpf_u_int32,
 	    struct sockaddr *, size_t, struct sockaddr *, size_t,
 	    struct sockaddr *, size_t, struct sockaddr *, size_t, char *);
 #endif
diff --git a/pcap-libdlpi.c b/pcap-libdlpi.c
index 933f2bdc..d004f62e 100644
--- a/pcap-libdlpi.c
+++ b/pcap-libdlpi.c
@@ -282,7 +282,7 @@ is_dlpi_interface(const char *name _U_)
  * additional network links present in the system.
  */
 int
-pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
+pcap_platform_finddevs(pcap_if_list_t *devlistp, char *errbuf)
 {
 	int retv = 0;
 
@@ -293,7 +293,8 @@ pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
 	/*
 	 * Get the list of regular interfaces first.
 	 */
-	if (pcap_findalldevs_interfaces(alldevsp, errbuf, is_dlpi_interface) == -1)
+	if (pcap_findalldevs_interfaces(devlistp, errbuf,
+	    is_dlpi_interface) == -1)
 		return (-1);	/* failure */
 
 	/* dlpi_walk() for loopback will be added here. */
@@ -320,7 +321,8 @@ pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
 		 * If it isn't already in the list of devices, try to
 		 * add it.
 		 */
-		if (find_or_add_dev(alldevsp, entry->linkname, 0, NULL, errbuf) == NULL)
+		if (find_or_add_dev(devlistp, entry->linkname, 0, NULL,
+		    errbuf) == NULL)
 			retv = -1;
 	}
 done:
diff --git a/pcap-linux.c b/pcap-linux.c
index b9a4bd77..d48fb8c3 100644
--- a/pcap-linux.c
+++ b/pcap-linux.c
@@ -2230,7 +2230,7 @@ pcap_stats_linux(pcap_t *handle, struct pcap_stat *stats)
 }
 
 static int
-add_linux_if(pcap_if_t **devlistp, const char *ifname, int fd, char *errbuf)
+add_linux_if(pcap_if_list_t *devlistp, const char *ifname, int fd, char *errbuf)
 {
 	const char *p;
 	char name[512];	/* XXX - pick a size */
@@ -2319,7 +2319,7 @@ add_linux_if(pcap_if_t **devlistp, const char *ifname, int fd, char *errbuf)
  * Otherwise, we return 1 if we don't get an error and -1 if we do.
  */
 static int
-scan_sys_class_net(pcap_if_t **devlistp, char *errbuf)
+scan_sys_class_net(pcap_if_list_t *devlistp, char *errbuf)
 {
 	DIR *sys_class_net_d;
 	int fd;
@@ -2437,7 +2437,7 @@ scan_sys_class_net(pcap_if_t **devlistp, char *errbuf)
  * See comments from scan_sys_class_net().
  */
 static int
-scan_proc_net_dev(pcap_if_t **devlistp, char *errbuf)
+scan_proc_net_dev(pcap_if_list_t *devlistp, char *errbuf)
 {
 	FILE *proc_net_f;
 	int fd;
@@ -2533,14 +2533,14 @@ can_be_bound(const char *name _U_)
 }
 
 int
-pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
+pcap_platform_finddevs(pcap_if_list_t *devlistp, char *errbuf)
 {
 	int ret;
 
 	/*
 	 * Get the list of regular interfaces first.
 	 */
-	if (pcap_findalldevs_interfaces(alldevsp, errbuf, can_be_bound) == -1)
+	if (pcap_findalldevs_interfaces(devlistp, errbuf, can_be_bound) == -1)
 		return (-1);	/* failure */
 
 	/*
@@ -2551,21 +2551,21 @@ pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
 	 * interfaces with no addresses, so you need to read "/sys/class/net"
 	 * to get the names of the rest of the interfaces.
 	 */
-	ret = scan_sys_class_net(alldevsp, errbuf);
+	ret = scan_sys_class_net(devlistp, errbuf);
 	if (ret == -1)
 		return (-1);	/* failed */
 	if (ret == 0) {
 		/*
 		 * No /sys/class/net; try reading /proc/net/dev instead.
 		 */
-		if (scan_proc_net_dev(alldevsp, errbuf) == -1)
+		if (scan_proc_net_dev(devlistp, errbuf) == -1)
 			return (-1);
 	}
 
 	/*
 	 * Add the "any" device.
 	 */
-	if (add_dev(alldevsp, "any", PCAP_IF_UP|PCAP_IF_RUNNING,
+	if (add_dev(devlistp, "any", PCAP_IF_UP|PCAP_IF_RUNNING,
 	    any_descr, errbuf) == NULL)
 		return (-1);
 
diff --git a/pcap-netfilter-linux.c b/pcap-netfilter-linux.c
index 446f5f08..49438cda 100644
--- a/pcap-netfilter-linux.c
+++ b/pcap-netfilter-linux.c
@@ -635,7 +635,7 @@ netfilter_create(const char *device, char *ebuf, int *is_ours)
 }
 
 int
-netfilter_findalldevs(pcap_if_t **alldevsp, char *err_str)
+netfilter_findalldevs(pcap_if_list_t *devlistp, char *err_str)
 {
 	int sock;
 
@@ -650,9 +650,9 @@ netfilter_findalldevs(pcap_if_t **alldevsp, char *err_str)
 	}
 	close(sock);
 
-	if (add_dev(alldevsp, NFLOG_IFACE, 0, "Linux netfilter log (NFLOG) interface", err_str) == NULL)
+	if (add_dev(devlistp, NFLOG_IFACE, 0, "Linux netfilter log (NFLOG) interface", err_str) == NULL)
 		return -1;
-	if (add_dev(alldevsp, NFQUEUE_IFACE, 0, "Linux netfilter queue (NFQUEUE) interface", err_str) == NULL)
+	if (add_dev(devlistp, NFQUEUE_IFACE, 0, "Linux netfilter queue (NFQUEUE) interface", err_str) == NULL)
 		return -1;
 	return 0;
 }
diff --git a/pcap-netfilter-linux.h b/pcap-netfilter-linux.h
index 01d9b394..97b73108 100644
--- a/pcap-netfilter-linux.h
+++ b/pcap-netfilter-linux.h
@@ -31,5 +31,5 @@
 /*
  * Prototypes for netlink-related functions
  */
-int netfilter_findalldevs(pcap_if_t **alldevsp, char *err_str);
+int netfilter_findalldevs(pcap_if_list_t *devlistp, char *err_str);
 pcap_t *netfilter_create(const char *device, char *ebuf, int *is_ours);
diff --git a/pcap-nit.c b/pcap-nit.c
index 1b626e21..19f10fc3 100644
--- a/pcap-nit.c
+++ b/pcap-nit.c
@@ -378,7 +378,7 @@ can_be_bound(const char *name _U_)
 }
 
 int
-pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
+pcap_platform_finddevs(pcap_if_list_t *devlistp, char *errbuf)
 {
-	return (pcap_findalldevs_interfaces(alldevsp, errbuf, can_be_bound));
+	return (pcap_findalldevs_interfaces(devlistp, errbuf, can_be_bound));
 }
diff --git a/pcap-null.c b/pcap-null.c
index b5fa3ab9..de20f227 100644
--- a/pcap-null.c
+++ b/pcap-null.c
@@ -43,11 +43,10 @@ pcap_create_interface(const char *device _U_, char *ebuf)
 }
 
 int
-pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
+pcap_platform_finddevs(pcap_if_list_t *devlistp, char *errbuf)
 {
 	/*
 	 * There are no interfaces on which we can capture.
 	 */
-	*alldevsp = NULL;
 	return (0);
 }
diff --git a/pcap-pf.c b/pcap-pf.c
index 73469086..97a33023 100644
--- a/pcap-pf.c
+++ b/pcap-pf.c
@@ -529,9 +529,9 @@ can_be_bound(const char *name _U_)
 }
 
 int
-pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
+pcap_platform_finddevs(pcap_if_list_t *devlistp, char *errbuf)
 {
-	return (pcap_findalldevs_interfaces(alldevsp, errbuf, can_be_bound));
+	return (pcap_findalldevs_interfaces(devlistp, errbuf, can_be_bound));
 }
 
 static int
diff --git a/pcap-septel.c b/pcap-septel.c
index e15b1d33..dc120dd5 100644
--- a/pcap-septel.c
+++ b/pcap-septel.c
@@ -252,7 +252,7 @@ static int septel_stats(pcap_t *p, struct pcap_stat *ps) {
 
 
 int
-septel_findalldevs(pcap_if_t **devlistp, char *errbuf)
+septel_findalldevs(pcap_if_list_t *devlistp, char *errbuf)
 {
   if (add_dev(devlistp,"septel",0,"Intel/Septel device",errbuf) == NULL)
     return -1;
@@ -303,9 +303,8 @@ septel_setnonblock(pcap_t *p, int nonblock, char *errbuf)
  * There are no regular interfaces, just Septel interfaces.
  */
 int
-pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
+pcap_platform_finddevs(pcap_if_list_t *devlistp, char *errbuf)
 {
-  *alldevsp = NULL;
   return (0);
 }
 
diff --git a/pcap-septel.h b/pcap-septel.h
index b6e1168b..0e648b20 100644
--- a/pcap-septel.h
+++ b/pcap-septel.h
@@ -10,4 +10,4 @@
  */
 
 pcap_t *septel_create(const char *device, char *ebuf, int *is_ours);
-int septel_findalldevs(pcap_if_t **devlistp, char *errbuf);
+int septel_findalldevs(pcap_if_list_t *devlistp, char *errbuf);
diff --git a/pcap-sita.c b/pcap-sita.c
index 1cd5f751..075aee77 100644
--- a/pcap-sita.c
+++ b/pcap-sita.c
@@ -821,9 +821,9 @@ static int acn_open_live(const char *name, char *errbuf, int *linktype) {		/* re
 	int			chassis, geoslot;
 	unit_t		*u;
 	iface_t		*p;
-	pcap_if_t	*alldevsp;
+	pcap_if_list_t	devlist;
 
-	pcap_platform_finddevs(&alldevsp, errbuf);
+	pcap_platform_finddevs(&devlist, errbuf);
 	for (chassis = 0; chassis <= MAX_CHASSIS; chassis++) {										/* scan the table... */
 		for (geoslot = 0; geoslot <= MAX_GEOSLOT; geoslot++) {
 			u = &units[chassis][geoslot];
@@ -1025,7 +1025,7 @@ pcap_t *pcap_create_interface(const char *device _U_, char *ebuf) {
 	return (p);
 }
 
-int pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf) {
+int pcap_platform_finddevs(pcap_if_list_t *devlistp, char *errbuf) {
 
 	//printf("pcap_findalldevs()\n");				// fulko
 
@@ -1042,7 +1042,7 @@ int pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf) {
 		//printf("pcap_findalldevs() returning BAD after findalldevs\n");				// fulko
 		return -1;
 		}
-	*alldevsp = acn_if_list;
+	devlistp->beginning = acn_if_list;
 	acn_if_list = 0;											/* then forget our list head, because someone will call pcap_freealldevs() to empty the malloc'ed stuff */
 	//printf("pcap_findalldevs() returning ZERO OK\n");				// fulko
 	return 0;
diff --git a/pcap-snf.c b/pcap-snf.c
index 1679d4df..ca0f3178 100644
--- a/pcap-snf.c
+++ b/pcap-snf.c
@@ -319,7 +319,7 @@ snf_activate(pcap_t* p)
 
 #define MAX_DESC_LENGTH 128
 int
-snf_findalldevs(pcap_if_t **devlistp, char *errbuf)
+snf_findalldevs(pcap_if_list_t *devlistp, char *errbuf)
 {
 	pcap_if_t *dev;
 	struct snf_ifaddrs *ifaddrs, *ifa;
@@ -393,7 +393,7 @@ snf_findalldevs(pcap_if_t **devlistp, char *errbuf)
 		 * See if there's already an entry for the device
 		 * with the name ifa->snf_ifa_name.
 		 */
-		dev = find_dev(alldevs, ifa->snf_ifa_name);
+		dev = find_dev(devlistp, ifa->snf_ifa_name);
 		if (dev != NULL) {
 			/*
 			 * Yes.  Update its description.
@@ -412,7 +412,7 @@ snf_findalldevs(pcap_if_t **devlistp, char *errbuf)
 			/*
 			 * No.  Add an entry for it.
 			 */
-			dev = add_dev(alldevs, ifa->snf_ifa_name, 0, desc,
+			dev = add_dev(devlistp, ifa->snf_ifa_name, 0, desc,
 			    errbuf);
 			if (dev == NULL)
 				return -1;
@@ -429,7 +429,7 @@ snf_findalldevs(pcap_if_t **devlistp, char *errbuf)
 		(void)pcap_snprintf(name,MAX_DESC_LENGTH,"snf%d",allports);
 		(void)pcap_snprintf(desc,MAX_DESC_LENGTH,"Myricom Merge Bitmask All Ports snf%d",
 			allports);
-		if (add_dev(alldevs, name, 0, desc, errbuf) == NULL)
+		if (add_dev(devlistp, name, 0, desc, errbuf) == NULL)
 			return (-1);
 		/*
 		 * XXX - should we give it a list of addresses with all
@@ -525,9 +525,8 @@ snf_create(const char *device, char *ebuf, int *is_ours)
  * There are no regular interfaces, just SNF interfaces.
  */
 int
-pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
+pcap_platform_finddevs(pcap_if_list_t *devlistp, char *errbuf)
 {
-	*alldevsp = NULL;
 	return (0);
 }
 
diff --git a/pcap-snf.h b/pcap-snf.h
index c9d7722b..ffc64adf 100644
--- a/pcap-snf.h
+++ b/pcap-snf.h
@@ -1,2 +1,2 @@
 pcap_t *snf_create(const char *, char *, int *);
-int snf_findalldevs(pcap_if_t **devlistp, char *errbuf);
+int snf_findalldevs(pcap_if_list_t *devlistp, char *errbuf);
diff --git a/pcap-snit.c b/pcap-snit.c
index 79349456..0c00860b 100644
--- a/pcap-snit.c
+++ b/pcap-snit.c
@@ -454,7 +454,7 @@ can_be_bound(const char *name _U_)
 }
 
 int
-pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
+pcap_platform_finddevs(pcap_if_list_t *devlistp, char *errbuf)
 {
-	return (pcap_findalldevs_interfaces(alldevsp, errbuf, can_be_bound));
+	return (pcap_findalldevs_interfaces(devlistp, errbuf, can_be_bound));
 }
diff --git a/pcap-snoop.c b/pcap-snoop.c
index 687b1d90..5eab4a2d 100644
--- a/pcap-snoop.c
+++ b/pcap-snoop.c
@@ -429,7 +429,7 @@ can_be_bound(const char *name _U_)
 }
 
 int
-pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
+pcap_platform_finddevs(pcap_if_list_t *devlistp, char *errbuf)
 {
-	return (pcap_findalldevs_interfaces(alldevsp, errbuf, can_be_bound));
+	return (pcap_findalldevs_interfaces(devlistp, errbuf, can_be_bound));
 }
diff --git a/pcap-usb-linux.c b/pcap-usb-linux.c
index 14305a77..bf9a4e5a 100644
--- a/pcap-usb-linux.c
+++ b/pcap-usb-linux.c
@@ -225,7 +225,7 @@ have_binary_usbmon(void)
 
 /* facility to add an USB device to the device list*/
 static int
-usb_dev_add(pcap_if_t** alldevsp, int n, char *err_str)
+usb_dev_add(pcap_if_list_t *devlistp, int n, char *err_str)
 {
 	char dev_name[10];
 	char dev_descr[30];
@@ -235,13 +235,13 @@ usb_dev_add(pcap_if_t** alldevsp, int n, char *err_str)
 	else
 		pcap_snprintf(dev_descr, 30, "USB bus number %d", n);
 
-	if (add_dev(alldevsp, dev_name, 0, dev_descr, err_str) == NULL)
+	if (add_dev(devlistp, dev_name, 0, dev_descr, err_str) == NULL)
 		return -1;
 	return 0;
 }
 
 int
-usb_findalldevs(pcap_if_t **alldevsp, char *err_str)
+usb_findalldevs(pcap_if_list_t *devlistp, char *err_str)
 {
 	char usb_mon_dir[PATH_MAX];
 	char *usb_mon_prefix;
@@ -292,7 +292,7 @@ usb_findalldevs(pcap_if_t **alldevsp, char *err_str)
 				if (sscanf(&name[usb_mon_prefix_len], "%d", &n) == 0)
 					continue;	/* failed */
 
-				ret = usb_dev_add(alldevsp, n, err_str);
+				ret = usb_dev_add(devlistp, n, err_str);
 			}
 
 			closedir(dir);
@@ -329,7 +329,7 @@ usb_findalldevs(pcap_if_t **alldevsp, char *err_str)
 				if (sscanf(&name[3], "%d", &n) == 0)
 					continue;
 
-				ret = usb_dev_add(alldevsp, n, err_str);
+				ret = usb_dev_add(devlistp, n, err_str);
 			}
 
 			closedir(dir);
@@ -350,7 +350,7 @@ usb_findalldevs(pcap_if_t **alldevsp, char *err_str)
 				if (sscanf(&name[len+1], "%d", &n) != 1)
 					continue;
 
-				ret = usb_dev_add(alldevsp, n, err_str);
+				ret = usb_dev_add(devlistp, n, err_str);
 			}
 
 			closedir(dir);
diff --git a/pcap-usb-linux.h b/pcap-usb-linux.h
index 234a262f..3ddc12f4 100644
--- a/pcap-usb-linux.h
+++ b/pcap-usb-linux.h
@@ -34,5 +34,5 @@
 /*
  * Prototypes for USB-related functions
  */
-int usb_findalldevs(pcap_if_t **alldevsp, char *err_str);
+int usb_findalldevs(pcap_if_list_t *devlistp, char *err_str);
 pcap_t *usb_create(const char *device, char *ebuf, int *is_ours);
diff --git a/pcap-win32.c b/pcap-win32.c
index b64c8a62..aa24a425 100644
--- a/pcap-win32.c
+++ b/pcap-win32.c
@@ -1346,7 +1346,7 @@ pcap_setnonblock_win32(pcap_t *p, int nonblock, char *errbuf)
 }
 
 static int
-pcap_add_if_win32(pcap_if_t **devlist, char *name, bpf_u_int32 flags,
+pcap_add_if_win32(pcap_if_list_t *devlistp, char *name, bpf_u_int32 flags,
     const char *description, char *errbuf)
 {
 	pcap_if_t *curdev;
@@ -1359,7 +1359,7 @@ pcap_add_if_win32(pcap_if_t **devlist, char *name, bpf_u_int32 flags,
 	/*
 	 * Add an entry for this interface, with no addresses.
 	 */
-	curdev = add_dev(devlist, name, flags, description, errbuf);
+	curdev = add_dev(devlistp, name, flags, description, errbuf);
 	if (curdev == NULL) {
 		/*
 		 * Failure.
@@ -1413,9 +1413,8 @@ pcap_add_if_win32(pcap_if_t **devlist, char *name, bpf_u_int32 flags,
 }
 
 int
-pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
+pcap_platform_finddevs(pcap_if_list_t *devlistp, char *errbuf)
 {
-	pcap_if_t *devlist = NULL;
 	int ret = 0;
 	const char *desc;
 	char *AdaptersName;
@@ -1454,13 +1453,9 @@ pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
 		}
 	}
 
-	if (NameLength > 0)
-		AdaptersName = (char*) malloc(NameLength);
-	else
-	{
-		*alldevsp = NULL;
+	if (NameLength <= 0)
 		return 0;
-	}
+	AdaptersName = (char*) malloc(NameLength);
 	if (AdaptersName == NULL)
 	{
 		pcap_snprintf(errbuf, PCAP_ERRBUF_SIZE, "Cannot allocate enough memory to list the adapters.");
@@ -1518,7 +1513,7 @@ pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
 		/*
 		 * Add an entry for this interface.
 		 */
-		if (pcap_add_if_win32(&devlist, name, flags, desc,
+		if (pcap_add_if_win32(devlistp, name, flags, desc,
 		    errbuf) == -1) {
 			/*
 			 * Failure.
@@ -1530,17 +1525,6 @@ pcap_platform_finddevs(pcap_if_t **alldevsp, char *errbuf)
 		desc += strlen(desc) + 1;
 	}
 
-	if (ret == -1) {
-		/*
-		 * We had an error; free the list we've been constructing.
-		 */
-		if (devlist != NULL) {
-			pcap_freealldevs(devlist);
-			devlist = NULL;
-		}
-	}
-
-	*alldevsp = devlist;
 	free(AdaptersName);
 	return (ret);
 }
diff --git a/pcap.c b/pcap.c
index ff47860c..9c2a2fac 100644
--- a/pcap.c
+++ b/pcap.c
@@ -315,8 +315,15 @@ pcap_next_ex(pcap_t *p, struct pcap_pkthdr **pkt_header,
 	return (p->read_op(p, 1, p->oneshot_callback, (u_char *)&s));
 }
 
+/*
+ * Implementation of a pcap_if_list_t.
+ */
+struct pcap_if_list {
+	pcap_if_t *beginning;
+};
+
 static struct capture_source_type {
-	int (*findalldevs_op)(pcap_if_t **, char *);
+	int (*findalldevs_op)(pcap_if_list_t *, char *);
 	pcap_t *(*create_op)(const char *, char *, int *);
 } capture_source_types[] = {
 #ifdef HAVE_DAG_API
@@ -359,32 +366,45 @@ int
 pcap_findalldevs(pcap_if_t **alldevsp, char *errbuf)
 {
 	size_t i;
+	pcap_if_list_t devlist;
 
 	/*
 	 * Find all the local network interfaces on which we
 	 * can capture.
 	 */
-	if (pcap_platform_finddevs(alldevsp, errbuf) == -1)
+	devlist.beginning = NULL;
+	if (pcap_platform_finddevs(&devlist, errbuf) == -1) {
+		/*
+		 * Failed - free all of the entries we were given
+		 * before we failed.
+		 */
+		if (devlist.beginning != NULL)
+			pcap_freealldevs(devlist.beginning);
+		*alldevsp = NULL;
 		return (-1);
+	}
 
 	/*
 	 * Ask each of the non-local-network-interface capture
 	 * source types what interfaces they have.
 	 */
 	for (i = 0; capture_source_types[i].findalldevs_op != NULL; i++) {
-		if (capture_source_types[i].findalldevs_op(alldevsp, errbuf) == -1) {
+		if (capture_source_types[i].findalldevs_op(&devlist, errbuf) == -1) {
 			/*
 			 * We had an error; free the list we've been
 			 * constructing.
 			 */
-			if (*alldevsp != NULL) {
-				pcap_freealldevs(*alldevsp);
-				*alldevsp = NULL;
-			}
+			if (devlist.beginning != NULL)
+				pcap_freealldevs(devlist.beginning);
+			*alldevsp = NULL;
 			return (-1);
 		}
 	}
 
+	/*
+	 * Return the first entry of the list of all devices.
+	 */
+	*alldevsp = devlist.beginning;
 	return (0);
 }
 
@@ -687,7 +707,7 @@ get_if_description(const char *name)
  * add interfaces even if they have no addresses.)
  */
 int
-add_addr_to_iflist(pcap_if_t **alldevs, const char *name, bpf_u_int32 flags,
+add_addr_to_iflist(pcap_if_list_t *alldevs, const char *name, bpf_u_int32 flags,
     struct sockaddr *addr, size_t addr_size,
     struct sockaddr *netmask, size_t netmask_size,
     struct sockaddr *broadaddr, size_t broadaddr_size,
@@ -849,7 +869,7 @@ add_addr_to_dev(pcap_if_t *curdev,
  * return -1 and set errbuf to an error message.
  */
 pcap_if_t *
-find_or_add_dev(pcap_if_t **alldevs, const char *name, bpf_u_int32 flags,
+find_or_add_dev(pcap_if_list_t *alldevs, const char *name, bpf_u_int32 flags,
     const char *description, char *errbuf)
 {
 	pcap_if_t *curdev;
@@ -876,14 +896,14 @@ find_or_add_dev(pcap_if_t **alldevs, const char *name, bpf_u_int32 flags,
  * the entry for it if we find it or NULL if we don't.
  */
 pcap_if_t *
-find_dev(pcap_if_t **alldevs, const char *name)
+find_dev(pcap_if_list_t *alldevs, const char *name)
 {
 	pcap_if_t *curdev;
 
 	/*
 	 * Is there an entry in the list for this device?
 	 */
-	for (curdev = *alldevs; curdev != NULL; curdev = curdev->next) {
+	for (curdev = alldevs->beginning; curdev != NULL; curdev = curdev->next) {
 		if (strcmp(name, curdev->name) == 0) {
 			/*
 			 * We found it, so, yes, there is.  No need to
@@ -909,7 +929,7 @@ find_dev(pcap_if_t **alldevs, const char *name)
  * If we weren't given a description, try to get one.
  */
 pcap_if_t *
-add_dev(pcap_if_t **alldevs, const char *name, bpf_u_int32 flags,
+add_dev(pcap_if_list_t *alldevs, const char *name, bpf_u_int32 flags,
     const char *description, char *errbuf)
 {
 	pcap_if_t *curdev, *prevdev, *nextdev;
@@ -976,7 +996,7 @@ add_dev(pcap_if_t **alldevs, const char *name, bpf_u_int32 flags,
 			/*
 			 * The next element is the first element.
 			 */
-			nextdev = *alldevs;
+			nextdev = alldevs->beginning;
 		} else
 			nextdev = prevdev->next;
 
@@ -1019,11 +1039,10 @@ add_dev(pcap_if_t **alldevs, const char *name, bpf_u_int32 flags,
 	 */
 	if (prevdev == NULL) {
 		/*
-		 * This is the first interface.  Pass back a
-		 * pointer to it, and put "curdev" before
-		 * "nextdev".
+		 * This is the first interface.  Make it
+		 * the first element in the list of devices.
 		 */
-		*alldevs = curdev;
+		alldevs->beginning = curdev;
 	} else
 		prevdev->next = curdev;
 	return (curdev);