1 /* Copyright (C) 1997, 1998, 1999, 2001 Free Software Foundation, Inc. 2 This file is part of the GNU C Library. 3 4 The GNU C Library is free software; you can redistribute it and/or 5 modify it under the terms of the GNU Lesser General Public 6 License as published by the Free Software Foundation; either 7 version 2.1 of the License, or (at your option) any later version. 8 9 The GNU C Library is distributed in the hope that it will be useful, 10 but WITHOUT ANY WARRANTY; without even the implied warranty of 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 Lesser General Public License for more details. 13 14 You should have received a copy of the GNU Lesser General Public 15 License along with the GNU C Library; if not, see 16 <http://www.gnu.org/licenses/>. */ 17 18 #ifndef _SYS_SELECT_H 19 # error "Never use <bits/select.h> directly; include <sys/select.h> instead." 20 #endif 21 22 23 #if defined __GNUC__ && __GNUC__ >= 2 24 25 # define __FD_ZERO(fdsp) \ 26 do { \ 27 int __d0, __d1; \ 28 __asm__ __volatile__ ("cld; rep; stosl" \ 29 : "=c" (__d0), "=D" (__d1) \ 30 : "a" (0), "0" (sizeof (fd_set) \ 31 / sizeof (__fd_mask)), \ 32 "1" (&__FDS_BITS (fdsp)[0]) \ 33 : "memory"); \ 34 } while (0) 35 36 # define __FD_SET(fd, fdsp) \ 37 __asm__ __volatile__ ("btsl %1,%0" \ 38 : "=m" (__FDS_BITS (fdsp)[__FDELT (fd)]) \ 39 : "r" (((int) (fd)) % __NFDBITS) \ 40 : "cc","memory") 41 # define __FD_CLR(fd, fdsp) \ 42 __asm__ __volatile__ ("btrl %1,%0" \ 43 : "=m" (__FDS_BITS (fdsp)[__FDELT (fd)]) \ 44 : "r" (((int) (fd)) % __NFDBITS) \ 45 : "cc","memory") 46 # define __FD_ISSET(fd, fdsp) \ 47 (__extension__ \ 48 ({register char __result; \ 49 __asm__ __volatile__ ("btl %1,%2 ; setcb %b0" \ 50 : "=q" (__result) \ 51 : "r" (((int) (fd)) % __NFDBITS), \ 52 "m" (__FDS_BITS (fdsp)[__FDELT (fd)]) \ 53 : "cc"); \ 54 __result; })) 55 56 #else /* ! GNU CC */ 57 58 /* We don't use `memset' because this would require a prototype and 59 the array isn't too big. */ 60 # define __FD_ZERO(set) \ 61 do { \ 62 unsigned int __i; \ 63 fd_set *__arr = (set); \ 64 for (__i = 0; __i < sizeof (fd_set) / sizeof (__fd_mask); ++__i) \ 65 __FDS_BITS (__arr)[__i] = 0; \ 66 } while (0) 67 # define __FD_SET(d, set) (__FDS_BITS (set)[__FDELT (d)] |= __FDMASK (d)) 68 # define __FD_CLR(d, set) (__FDS_BITS (set)[__FDELT (d)] &= ~__FDMASK (d)) 69 # define __FD_ISSET(d, set) (__FDS_BITS (set)[__FDELT (d)] & __FDMASK (d)) 70 71 #endif /* GNU CC */ 72