projects / thirdparty / glibc.git / blame
| Commit | Line | Data |
|---|---|---|
| 0ecb606c | 1 | /* Copyright (C) 1999,2002,2003,2004,2005,2006 Free Software Foundation, Inc. |
| 9c7ff11a UD |
2 | This file is part of the GNU C Library. |
| 3 | Contributed by Andreas Jaeger <aj@suse.de>. | |
| 4 | ||
| 5 | The GNU C Library is free software; you can redistribute it and/or | |
| 6 | modify it under the terms of the GNU Lesser General Public | |
| 7 | License as published by the Free Software Foundation; either | |
| 8 | version 2.1 of the License, or (at your option) any later version. | |
| 9 | ||
| 10 | The GNU C Library is distributed in the hope that it will be useful, | |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 13 | Lesser General Public License for more details. | |
| 14 | ||
| 15 | You should have received a copy of the GNU Lesser General Public | |
| 16 | License along with the GNU C Library; if not, write to the Free | |
| 17 | Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA | |
| 18 | 02111-1307 USA. */ | |
| 19 | ||
| 20 | #include "ifreq.h" | |
| 0ecb606c | 21 | #include <kernel-features.h> |
| 9c7ff11a | 22 | |
| 25337753 UD |
23 | /* Variable to signal whether SIOCGIFCONF is not available. */ |
| 24 | #if __ASSUME_SIOCGIFNAME == 0 || 1 | |
| 25 | static int old_siocgifconf; | |
| 26 | #else | |
| 27 | # define old_siocgifconf 0 | |
| 28 | #endif | |
| 29 | ||
| 9c7ff11a UD |
30 | |
| 31 | void | |
| 32 | __ifreq (struct ifreq **ifreqs, int *num_ifs, int sockfd) | |
| 33 | { | |
| 34 | int fd = sockfd; | |
| 35 | struct ifconf ifc; | |
| 36 | int rq_len; | |
| 37 | int nifs; | |
| 38 | # define RQ_IFS 4 | |
| 39 | ||
| 40 | if (fd < 0) | |
| 41 | fd = __opensock (); | |
| 42 | if (fd < 0) | |
| 43 | { | |
| 44 | *num_ifs = 0; | |
| 45 | *ifreqs = NULL; | |
| 46 | return; | |
| 47 | } | |
| 48 | ||
| 49 | ifc.ifc_buf = NULL; | |
| 50 | ||
| 51 | /* We may be able to get the needed buffer size directly, rather than | |
| 52 | guessing. */ | |
| 53 | if (! old_siocgifconf) | |
| 54 | { | |
| 55 | ifc.ifc_buf = NULL; | |
| 56 | ifc.ifc_len = 0; | |
| 57 | if (__ioctl (fd, SIOCGIFCONF, &ifc) < 0 || ifc.ifc_len == 0) | |
| 58 | { | |
| 59 | # if __ASSUME_SIOCGIFNAME == 0 | |
| 60 | old_siocgifconf = 1; | |
| 61 | # endif | |
| 62 | rq_len = RQ_IFS * sizeof (struct ifreq); | |
| 63 | } | |
| 64 | else | |
| 65 | rq_len = ifc.ifc_len; | |
| 66 | } | |
| 67 | else | |
| 68 | rq_len = RQ_IFS * sizeof (struct ifreq); | |
| 69 | ||
| 70 | /* Read all the interfaces out of the kernel. */ | |
| 71 | while (1) | |
| 72 | { | |
| 73 | ifc.ifc_len = rq_len; | |
| 9be31a51 | 74 | void *newp = realloc (ifc.ifc_buf, ifc.ifc_len); |
| f3285f86 UD |
75 | if (newp == NULL |
| 76 | || (ifc.ifc_buf = newp, __ioctl (fd, SIOCGIFCONF, &ifc)) < 0) | |
| 9c7ff11a | 77 | { |
| 9be31a51 | 78 | free (ifc.ifc_buf); |
| 9c7ff11a UD |
79 | |
| 80 | if (fd != sockfd) | |
| 81 | __close (fd); | |
| 82 | ||
| 83 | *num_ifs = 0; | |
| 84 | *ifreqs = NULL; | |
| 85 | return; | |
| 86 | } | |
| 87 | ||
| 88 | if (!old_siocgifconf || ifc.ifc_len < rq_len) | |
| 89 | break; | |
| 90 | ||
| 91 | rq_len *= 2; | |
| 92 | } | |
| 93 | ||
| 94 | nifs = ifc.ifc_len / sizeof (struct ifreq); | |
| 95 | ||
| 96 | if (fd != sockfd) | |
| 97 | __close (fd); | |
| 98 | ||
| 99 | *num_ifs = nifs; | |
| 100 | *ifreqs = realloc (ifc.ifc_buf, nifs * sizeof (struct ifreq)); | |
| 101 | } |