From ba763af5599bf80e488b98a1cf973c2388eeeac9 Mon Sep 17 00:00:00 2001
From: Corinna Vinschen <corinna@vinschen.de>
Date: Thu, 13 Jun 2013 19:37:14 +0000
Subject: [PATCH] 	* net.cc (gen_old_if_name): New function to generate
 short interface 	names for old pre-1.7 applications. 	(get_ifs):
 Call gen_old_if_name for said old applications.

---
 winsup/cygwin/ChangeLog |  6 +++++
 winsup/cygwin/net.cc    | 54 +++++++++++++++++++++++++++++++++++++++--
 2 files changed, 58 insertions(+), 2 deletions(-)

diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index 913084bd4..eaa0373ee 100644
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,3 +1,9 @@
+2013-06-13  Corinna Vinschen  <corinna@vinschen.de>
+
+	* net.cc (gen_old_if_name): New function to generate short interface
+	names for old pre-1.7 applications.
+	(get_ifs): Call gen_old_if_name for said old applications.
+
 2013-06-13  Corinna Vinschen  <corinna@vinschen.de>
 
 	* posix.sgml (fcntl, flock, lockf): Point to implementation notes.
diff --git a/winsup/cygwin/net.cc b/winsup/cygwin/net.cc
index 0454d9b32..053c66718 100644
--- a/winsup/cygwin/net.cc
+++ b/winsup/cygwin/net.cc
@@ -1900,6 +1900,51 @@ get_hwaddr (struct ifall *ifp, PIP_ADAPTER_ADDRESSES pap)
       ifp->ifa_hwaddr.sa_data[i] = pap->PhysicalAddress[i];
 }
 
+/*
+ * Generate short, unique interface name for usage with aged
+ * applications still using the old pre-1.7 ifreq structure.
+ */
+static void
+gen_old_if_name (char *name, PIP_ADAPTER_ADDRESSES pap, DWORD idx)
+{
+  /* Note: The returned name must be < 16 chars. */
+  const char *prefix;
+
+  switch (pap->IfType)
+    {
+      case IF_TYPE_ISO88025_TOKENRING:
+	prefix = "tok";
+	break;
+      case IF_TYPE_PPP:
+	prefix = "ppp";
+	break;
+      case IF_TYPE_SOFTWARE_LOOPBACK:
+      	prefix = "lo";
+	break;
+      case IF_TYPE_ATM:
+      	prefix = "atm";
+	break;
+      case IF_TYPE_IEEE80211:
+      	prefix = "wlan";
+	break;
+      case IF_TYPE_SLIP:
+      case IF_TYPE_RS232:
+      case IF_TYPE_MODEM:
+	prefix = "slp";
+	break;
+      case IF_TYPE_TUNNEL:
+      	prefix = "tun";
+	break;
+      default:
+	prefix = "eth";
+	break;
+    }
+  if (idx)
+    __small_sprintf (name, "%s%u:%u", prefix, pap->IfIndex, idx);
+  else
+    __small_sprintf (name, "%s%u", prefix, pap->IfIndex, idx);
+}
+
 /*
  * Get network interfaces.  Use IP Helper function GetAdaptersAddresses.
  */
@@ -1941,7 +1986,10 @@ get_ifs (ULONG family)
 	    /* Next in chain */
 	    ifp->ifa_ifa.ifa_next = (struct ifaddrs *) &ifp[1].ifa_ifa;
 	    /* Interface name */
-	    if (idx)
+
+	    if (CYGWIN_VERSION_CHECK_FOR_OLD_IFREQ)
+	      gen_old_if_name (ifp->ifa_name, pap, idx);
+	    else if (idx)
 	      __small_sprintf (ifp->ifa_name, "%s:%u", pap->AdapterName, idx);
 	    else
 	      strcpy (ifp->ifa_name, pap->AdapterName);
@@ -1985,7 +2033,9 @@ get_ifs (ULONG family)
 	    /* Next in chain */
 	    ifp->ifa_ifa.ifa_next = (struct ifaddrs *) &ifp[1].ifa_ifa;
 	    /* Interface name */
-	    if (sa->sa_family == AF_INET && idx)
+	    if (CYGWIN_VERSION_CHECK_FOR_OLD_IFREQ)
+	      gen_old_if_name (ifp->ifa_name, pap, idx);
+	    else if (sa->sa_family == AF_INET && idx)
 	      __small_sprintf (ifp->ifa_name, "%s:%u", pap->AdapterName, idx);
 	    else
 	      strcpy (ifp->ifa_name, pap->AdapterName);