diff options
Diffstat (limited to 'REORG.TODO/sysdeps/unix/sysv/linux/ifreq.c')
-rw-r--r-- | REORG.TODO/sysdeps/unix/sysv/linux/ifreq.c | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/unix/sysv/linux/ifreq.c b/REORG.TODO/sysdeps/unix/sysv/linux/ifreq.c new file mode 100644 index 0000000000..d941ba1a93 --- /dev/null +++ b/REORG.TODO/sysdeps/unix/sysv/linux/ifreq.c @@ -0,0 +1,74 @@ +/* Copyright (C) 1999-2017 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, see + <http://www.gnu.org/licenses/>. */ + +#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; + + /* We may be able to get the needed buffer size directly, rather than + guessing. */ + ifc.ifc_buf = NULL; + ifc.ifc_len = 0; + if (__ioctl (fd, SIOCGIFCONF, &ifc) < 0 || ifc.ifc_len == 0) + rq_len = RQ_IFS * sizeof (struct ifreq); + else + rq_len = ifc.ifc_len; + + /* Read all the interfaces out of the kernel. */ + ifc.ifc_len = rq_len; + void *newp = realloc (ifc.ifc_buf, ifc.ifc_len); + if (newp == NULL + || (ifc.ifc_buf = newp, __ioctl (fd, SIOCGIFCONF, &ifc)) < 0) + { + free (ifc.ifc_buf); + + if (fd != sockfd) + __close (fd); + + *num_ifs = 0; + *ifreqs = NULL; + return; + } + + nifs = ifc.ifc_len / sizeof (struct ifreq); + + if (fd != sockfd) + __close (fd); + + *num_ifs = nifs; + *ifreqs = realloc (ifc.ifc_buf, nifs * sizeof (struct ifreq)); +} |