diff options
Diffstat (limited to 'inet/ifreq.c')
-rw-r--r-- | inet/ifreq.c | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/inet/ifreq.c b/inet/ifreq.c new file mode 100644 index 0000000..55e833b --- /dev/null +++ b/inet/ifreq.c @@ -0,0 +1,80 @@ +/* Copyright (C) 1999, 2002, 2003, 2004 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Andreas Jaeger <aj@suse.de>. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include "ifreq.h" + + +void +__ifreq (struct ifreq **ifreqs, int *num_ifs, int sockfd) +{ + int fd = sockfd; + struct ifconf ifc; + int rq_len; + int nifs; +# define RQ_IFS 4 + + if (fd < 0) + fd = __opensock (); + if (fd < 0) + { + *num_ifs = 0; + *ifreqs = NULL; + return; + } + + ifc.ifc_buf = NULL; + rq_len = RQ_IFS * sizeof (struct ifreq) / 2; /* Doubled in the loop. */ + do + { + ifc.ifc_len = rq_len *= 2; + void *newp = realloc (ifc.ifc_buf, ifc.ifc_len); + if (newp == NULL || __ioctl (fd, SIOCGIFCONF, &ifc) < 0) + { + free (ifc.ifc_buf); + + if (fd != sockfd) + __close (fd); + *num_ifs = 0; + *ifreqs = NULL; + return; + } + ifc.ifc_buf = newp; + } + while (rq_len < sizeof (struct ifreq) + ifc.ifc_len); + + if (fd != sockfd) + __close (fd); + +#ifdef _HAVE_SA_LEN + struct ifreq *ifr = *ifreqs; + nifs = 0; + while ((char *) ifr < ifc.ifc_buf + ifc.ifc_len) + { + ++nifs; + ifr = __if_nextreq (ifr); + if (ifr == NULL) + break; + } +#else + nifs = ifc.ifc_len / sizeof (struct ifreq); +#endif + + *num_ifs = nifs; + *ifreqs = realloc (ifc.ifc_buf, nifs * sizeof (struct ifreq)); +} |