[Emacs-diffs] /srv/bzr/emacs/trunk r105487: * src/process.c (Fnetwork_interface_list): Correctly determine buffer

[Andreas Schwab]

------------------------------------------------------------
revno: 105487
committer: Andreas Schwab <address@hidden>
branch nick: emacs
timestamp: Thu 2011-08-18 17:33:22 +0200
message:
  * src/process.c (Fnetwork_interface_list): Correctly determine buffer
  size.
modified:
  src/ChangeLog
  src/process.c

=== modified file 'src/ChangeLog'
--- a/src/ChangeLog     2011-08-17 21:40:13 +0000
+++ b/src/ChangeLog     2011-08-18 15:33:22 +0000
@@ -1,3 +1,8 @@
+2011-08-18  Andreas Schwab  <address@hidden>
+
+       * process.c (Fnetwork_interface_list): Correctly determine buffer
+       size.
+
 2011-08-17  Chong Yidong  <address@hidden>
 
        * eval.c (internal_condition_case, internal_condition_case_1)

=== modified file 'src/process.c'
--- a/src/process.c     2011-08-14 17:51:08 +0000
+++ b/src/process.c     2011-08-18 15:33:22 +0000
@@ -3580,38 +3580,57 @@
   if (s < 0)
     return Qnil;
 
- again:
-  buf_size *= 2;
-  buf = xrealloc(buf, buf_size);
-  if (!buf)
-    {
-      close (s);
-      return Qnil;
-    }
-
-  ifconf.ifc_buf = buf;
-  if (ioctl (s, SIOCGIFCONF, &ifconf))
-    {
-      close (s);
-      xfree (buf);
-      return Qnil;
-    }
-
-  if (ifconf.ifc_len == buf_size)
-    goto again;
+  ifconf.ifc_buf = 0;
+  ifconf.ifc_len = 0;
+  if (ioctl (s, SIOCGIFCONF, &ifconf) == 0 && ifconf.ifc_len > 0)
+    {
+      ifconf.ifc_buf = xmalloc (ifconf.ifc_len);
+      if (ifconf.ifc_buf == NULL)
+       {
+         close (s);
+         return Qnil;
+       }
+      if (ioctl (s, SIOCGIFCONF, &ifconf))
+       {
+         close (s);
+         xfree (ifconf.ifc_buf);
+         return Qnil;
+       }
+    }
+  else
+    do
+      {
+       buf_size *= 2;
+       buf = xrealloc (buf, buf_size);
+       if (!buf)
+         {
+           close (s);
+           return Qnil;
+         }
+
+       ifconf.ifc_buf = buf;
+       ifconf.ifc_len = buf_size;
+       if (ioctl (s, SIOCGIFCONF, &ifconf))
+         {
+           close (s);
+           xfree (buf);
+           return Qnil;
+         }
+
+      }
+    while (ifconf.ifc_len == buf_size);
 
   close (s);
 
   res = Qnil;
-  for (ifreq = ifconf.ifc_req;
-       (char *) ifreq < (char *) (ifconf.ifc_req) + ifconf.ifc_len;
-       )
+  ifreq = ifconf.ifc_req;
+  while ((char *) ifreq < (char *) ifconf.ifc_req + ifconf.ifc_len)
     {
       struct ifreq *ifq = ifreq;
 #ifdef HAVE_STRUCT_IFREQ_IFR_ADDR_SA_LEN
-#define SIZEOF_IFREQ(sif)                                               \
-      ((sif)->ifr_addr.sa_len < sizeof(struct sockaddr) ?               \
-       sizeof((*sif)) : sizeof ((sif)->ifr_name) + sif->ifr_addr.sa_len)
+#define SIZEOF_IFREQ(sif)                                              \
+      ((sif)->ifr_addr.sa_len < sizeof (struct sockaddr)               \
+       ? sizeof (*(sif)) : sizeof ((sif)->ifr_name) + (sif)->ifr_addr.sa_len)
 
       int len = SIZEOF_IFREQ (ifq);
 #else
@@ -3619,7 +3638,7 @@
 #endif
       char namebuf[sizeof (ifq->ifr_name) + 1];
       i += len;
-      ifreq = (struct ifreq*) ((char*) ifreq + len);
+      ifreq = (struct ifreq *) ((char *) ifreq + len);
 
       if (ifq->ifr_addr.sa_family != AF_INET)
        continue;