sysdeps/unix/sysv/linux/kernel-features.h

   1 /* Set flags signalling availability of kernel features based on given
   2    kernel version number.
   3    Copyright (C) 1999, 2000 Free Software Foundation, Inc.
   4    This file is part of the GNU C Library.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Library General Public License as
   8    published by the Free Software Foundation; either version 2 of the
   9    License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Library General Public License for more details.
  15
  16    You should have received a copy of the GNU Library General Public
  17    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  18    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 /* This file must not contain any C code.  At least it must be protected
  22    to allow using the file also in assembler files.  */
  23
  24 #ifndef __LINUX_KERNEL_VERSION
  25 /* We assume the worst; all kernels should be supported.  */
  26 # define __LINUX_KERNEL_VERSION 0
  27 #endif
  28
  29 /* We assume for __LINUX_KERNEL_VERSION the same encoding used in
  30    linux/version.h.  I.e., the major, minor, and subminor all get a
  31    byte with the major number being in the highest byte.  This means
  32    we can do numeric comparisons.
  33
  34    In the following we will define certain symbols depending on
  35    whether the describes kernel feature is available in the kernel
  36    version given by __LINUX_KERNEL_VERSION.  We are not always exactly
  37    recording the correct versions in which the features were
  38    introduced.  If somebody cares these values can afterwards be
  39    corrected.  Most of the numbers here are set corresponding to
  40    2.2.0.  */
  41
  42 /* `getcwd' system call.  */
  43 #if __LINUX_KERNEL_VERSION >= 131584
  44 # define __ASSUME_GETCWD_SYSCALL        1
  45 #endif
  46
  47 /* Real-time signal became usable in 2.1.70.  */
  48 #if __LINUX_KERNEL_VERSION >= 131398
  49 # define __ASSUME_REALTIME_SIGNALS      1
  50 #endif
  51
  52 /* When were the `pread'/`pwrite' syscalls introduced?  */
  53 #if __LINUX_KERNEL_VERSION >= 131584
  54 # define __ASSUME_PREAD_SYSCALL         1
  55 # define __ASSUME_PWRITE_SYSCALL        1
  56 #endif
  57
  58 /* When was `poll' introduced?  */
  59 #if __LINUX_KERNEL_VERSION >= 131584
  60 # define __ASSUME_POLL_SYSCALL          1
  61 #endif
  62
  63 /* The `lchown' syscall was introduced in 2.1.80.  */
  64 #if __LINUX_KERNEL_VERSION >= 131408
  65 # define __ASSUME_LCHOWN_SYSCALL        1
  66 #endif
  67
  68 /* When did the `setresuid' sysall became available?  */
  69 #if __LINUX_KERNEL_VERSION >= 131584 && !defined __sparc__
  70 # define __ASSUME_SETRESUID_SYSCALL     1
  71 #endif
  72
  73 /* The SIOCGIFNAME ioctl is available starting with 2.1.50.  */
  74 #if __LINUX_KERNEL_VERSION >= 131408
  75 # define __ASSUME_SIOCGIFNAME           1
  76 #endif
  77
  78 /* On x86 another `getrlimit' syscall was added in 2.3.25.  */
  79 #if __LINUX_KERNEL_VERSION >= 131865 && defined __i386__
  80 # define __ASSUME_NEW_GETRLIMIT_SYSCALL 1
  81 #endif
  82
  83 /* On x86 the truncate64/ftruncate64 syscalls were introduced in 2.3.31.  */
  84 #if __LINUX_KERNEL_VERSION >= 131871 && defined __i386__
  85 # define __ASSUME_TRUNCATE64_SYSCALL    1
  86 #endif
  87
  88 /* On x86 the mmap2 syscall was introduced in 2.3.31.  */
  89 #if __LINUX_KERNEL_VERSION >= 131871 && defined __i386__
  90 # define __ASSUME_MMAP2_SYSCALL 1
  91 #endif
  92
  93 /* On x86 the stat64/lstat64/fstat64 syscalls were introduced in 2.3.34.  */
  94 #if __LINUX_KERNEL_VERSION >= 131874 && defined __i386__
  95 # define __ASSUME_STAT64_SYSCALL        1
  96 #endif
  97
  98 /* On sparc and ARM the truncate64/ftruncate64/mmap2/stat64/lstat64/fstat64
  99    syscalls were introduced in 2.3.35.  */
 100 #if __LINUX_KERNEL_VERSION >= 131875 && (defined __sparc__ || defined __arm__)
 101 # define __ASSUME_TRUNCATE64_SYSCALL    1
 102 # define __ASSUME_MMAP2_SYSCALL         1
 103 # define __ASSUME_STAT64_SYSCALL        1
 104 #endif
 105
 106 /* I know for sure that these are in 2.3.35 on powerpc.  */
 107 #if __LINUX_KERNEL_VERSION >= 131875 && defined __powerpc__
 108 # define __ASSUME_TRUNCATE64_SYSCALL    1
 109 # define __ASSUME_STAT64_SYSCALL        1
 110 # define __ASSUME_NEW_GETRLIMIT_SYSCALL 1
 111 #endif
 112
 113 /* Linux 2.3.39 introduced 32bit UID/GIDs.  */
 114 #if __LINUX_KERNEL_VERSION >= 131879
 115 # define __ASSUME_32BITUIDS             1
 116 # ifdef __sparc__
 117 #  define __ASSUME_SETRESUID_SYSCALL    1
 118 # endif
 119 #endif
 120
 121 /* We can use the LDTs for threading with Linux 2.3.99 and newer.  */
 122 #if __LINUX_KERNEL_VERSION >= 131939
 123 # define __ASSUME_LDT_WORKS             1
 124 #endif