Here is a diff of /usr/src/usr.sbin/ppp against current. The diffs

add some logging functionality which I find very useful.
'set debug link' will record just link up/down and address assignments.
'set debug connect' will record the entire chat dialog
'set debug carrier' will record just chat lines including 'CARRIER'
(so that I can be sure I'm getting a 28.8 line).

There was a global change required to permit LogPrintf to take a bit
mask instead of a bit position value (to permit logging some events
on either of two flags, so that no change in 'set debug lcp' would
result from the code supporting 'link'.  Thus the diffs are rather
long for such a small change.  The man page is also touched.

Oh, and there was a slight syntax problem in route.c

Reviewed by:	phk
Submitted by:	Tony Kimball <alk@Think.COM>

1 files changed, 24 insertions, 14 deletions

diff --git a/usr.sbin/ppp/os.c b/usr.sbin/ppp/os.c
index 691e258..f42318d 100644
--- a/usr.sbin/ppp/os.c
+++ b/usr.sbin/ppp/os.c
@@ -17,7 +17,7 @@
  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  *
- * $Id: os.c,v 1.3 1995/05/30 03:50:52 rgrimes Exp $
+ * $Id: os.c,v 1.4 1996/01/11 17:48:55 phk Exp $
  *
  */
 #include "fsm.h"
@@ -181,7 +181,7 @@ OsLinkup()
 	logprintf("setuid failed\n");
     peer_addr = IpcpInfo.his_ipaddr;
     s = (char *)inet_ntoa(peer_addr);
-    LogPrintf(LOG_PHASE, "OsLinkup: %s\n", s);
+    LogPrintf(LOG_LINK_BIT|LOG_LCP_BIT, "OsLinkup: %s\n", s);
 
     if (SelectSystem(inet_ntoa(IpcpInfo.want_ipaddr), LINKFILE) < 0) {
       if (dstsystem) {
@@ -201,7 +201,7 @@ OsLinkdown()
 
   if (linkup) {
     s = (char *)inet_ntoa(peer_addr);
-    LogPrintf(LOG_PHASE, "OsLinkdown: %s\n", s);
+    LogPrintf(LOG_LINK_BIT|LOG_LCP_BIT, "OsLinkdown: %s\n", s);
     if (!(mode & MODE_AUTO))
       DeleteIfRoutes(0);
     linkup = 0;
@@ -253,25 +253,35 @@ int type, mtu, speed;
 /*
  *  Open tunnel device and returns its descriptor
  */
+
+#define MAX_TUN 256
+/* MAX_TUN is set at an arbitrarily large value  *
+ * as the loop aborts when it reaches the first  *
+ * 'Device not configured' (ENXIO), or the third *
+ * 'No such file or directory' (ENOENT) error.   */
 int
 OpenTunnel(ptun)
 int *ptun;
 {
   int s;
-  char *cp;
-  char *suffix = "0123456789";
   char ifname[IFNAMSIZ];
-  char devname[12];
+  char devname[14];  /* sufficient room for "/dev/tun65535" */
+  unsigned unit, enoentcount=0;
 
-  strcpy(devname, "/dev/tun0");
-  for (cp = suffix; *cp; cp++) {
-    devname[8] = *cp;
+  for( unit=0; unit <= MAX_TUN ; unit++ ) {
+    sprintf( devname, "/dev/tun%d", unit );
     tun_out = open(devname, O_RDWR);
-    if (tun_out >= 0)
-      break;
+    if( tun_out >= 0 )
+	break;
+    if( errno == ENXIO )
+	unit=MAX_TUN+1;
+    else if( errno == ENOENT ) {
+	enoentcount++;
+	if( enoentcount > 2 )
+		unit=MAX_TUN+1;
+    }
   }
-  *ptun = cp - suffix;
-  if (*cp == '\0') {
+  if( unit > MAX_TUN ) {
     fprintf(stderr, "No tunnel device is available.\n");
     return(-1);
   }
@@ -317,7 +327,7 @@ int *ptun;
     return(-1);
   }
   printf("Using interface: %s\r\n", IfDevName);
-  LogPrintf(LOG_PHASE, "Using interface: %s\n", IfDevName);
+  LogPrintf(LOG_PHASE_BIT, "Using interface: %s\n", IfDevName);
   close(s);
   return(0);
 }