| 1 | /* `fd_set' type and related macros, and `select'/`pselect' declarations. |
|---|---|
| 2 | Copyright (C) 1996-2016 Free Software Foundation, Inc. |
| 3 | This file is part of the GNU C Library. |
| 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, see |
| 17 | <http://www.gnu.org/licenses/>. */ |
| 18 | |
| 19 | /* POSIX 1003.1g: 6.2 Select from File Descriptor Sets <sys/select.h> */ |
| 20 | |
| 21 | #ifndef _SYS_SELECT_H |
| 22 | #define _SYS_SELECT_H 1 |
| 23 | |
| 24 | #include <features.h> |
| 25 | |
| 26 | /* Get definition of needed basic types. */ |
| 27 | #include <bits/types.h> |
| 28 | |
| 29 | /* Get __FD_* definitions. */ |
| 30 | #include <bits/select.h> |
| 31 | |
| 32 | /* Get __sigset_t. */ |
| 33 | #include <bits/sigset.h> |
| 34 | |
| 35 | #ifndef __sigset_t_defined |
| 36 | # define __sigset_t_defined |
| 37 | typedef __sigset_t sigset_t; |
| 38 | #endif |
| 39 | |
| 40 | /* Get definition of timer specification structures. */ |
| 41 | #define __need_time_t |
| 42 | #define __need_timespec |
| 43 | #include <time.h> |
| 44 | #define __need_timeval |
| 45 | #include <bits/time.h> |
| 46 | |
| 47 | #ifndef __suseconds_t_defined |
| 48 | typedef __suseconds_t suseconds_t; |
| 49 | # define __suseconds_t_defined |
| 50 | #endif |
| 51 | |
| 52 | |
| 53 | /* The fd_set member is required to be an array of longs. */ |
| 54 | typedef long int __fd_mask; |
| 55 | |
| 56 | /* Some versions of <linux/posix_types.h> define this macros. */ |
| 57 | #undef __NFDBITS |
| 58 | /* It's easier to assume 8-bit bytes than to get CHAR_BIT. */ |
| 59 | #define __NFDBITS (8 * (int) sizeof (__fd_mask)) |
| 60 | #define __FD_ELT(d) ((d) / __NFDBITS) |
| 61 | #define __FD_MASK(d) ((__fd_mask) (1UL << ((d) % __NFDBITS))) |
| 62 | |
| 63 | /* fd_set for select and pselect. */ |
| 64 | typedef struct |
| 65 | { |
| 66 | /* XPG4.2 requires this member name. Otherwise avoid the name |
| 67 | from the global namespace. */ |
| 68 | #ifdef __USE_XOPEN |
| 69 | __fd_mask fds_bits[__FD_SETSIZE / __NFDBITS]; |
| 70 | # define __FDS_BITS(set) ((set)->fds_bits) |
| 71 | #else |
| 72 | __fd_mask __fds_bits[__FD_SETSIZE / __NFDBITS]; |
| 73 | # define __FDS_BITS(set) ((set)->__fds_bits) |
| 74 | #endif |
| 75 | } fd_set; |
| 76 | |
| 77 | /* Maximum number of file descriptors in `fd_set'. */ |
| 78 | #define FD_SETSIZE __FD_SETSIZE |
| 79 | |
| 80 | #ifdef __USE_MISC |
| 81 | /* Sometimes the fd_set member is assumed to have this type. */ |
| 82 | typedef __fd_mask fd_mask; |
| 83 | |
| 84 | /* Number of bits per word of `fd_set' (some code assumes this is 32). */ |
| 85 | # define NFDBITS __NFDBITS |
| 86 | #endif |
| 87 | |
| 88 | |
| 89 | /* Access macros for `fd_set'. */ |
| 90 | #define FD_SET(fd, fdsetp) __FD_SET (fd, fdsetp) |
| 91 | #define FD_CLR(fd, fdsetp) __FD_CLR (fd, fdsetp) |
| 92 | #define FD_ISSET(fd, fdsetp) __FD_ISSET (fd, fdsetp) |
| 93 | #define FD_ZERO(fdsetp) __FD_ZERO (fdsetp) |
| 94 | |
| 95 | |
| 96 | __BEGIN_DECLS |
| 97 | |
| 98 | /* Check the first NFDS descriptors each in READFDS (if not NULL) for read |
| 99 | readiness, in WRITEFDS (if not NULL) for write readiness, and in EXCEPTFDS |
| 100 | (if not NULL) for exceptional conditions. If TIMEOUT is not NULL, time out |
| 101 | after waiting the interval specified therein. Returns the number of ready |
| 102 | descriptors, or -1 for errors. |
| 103 | |
| 104 | This function is a cancellation point and therefore not marked with |
| 105 | __THROW. */ |
| 106 | extern int select (int __nfds, fd_set *__restrict __readfds, |
| 107 | fd_set *__restrict __writefds, |
| 108 | fd_set *__restrict __exceptfds, |
| 109 | struct timeval *__restrict __timeout); |
| 110 | |
| 111 | #ifdef __USE_XOPEN2K |
| 112 | /* Same as above only that the TIMEOUT value is given with higher |
| 113 | resolution and a sigmask which is been set temporarily. This version |
| 114 | should be used. |
| 115 | |
| 116 | This function is a cancellation point and therefore not marked with |
| 117 | __THROW. */ |
| 118 | extern int pselect (int __nfds, fd_set *__restrict __readfds, |
| 119 | fd_set *__restrict __writefds, |
| 120 | fd_set *__restrict __exceptfds, |
| 121 | const struct timespec *__restrict __timeout, |
| 122 | const __sigset_t *__restrict __sigmask); |
| 123 | #endif |
| 124 | |
| 125 | |
| 126 | /* Define some inlines helping to catch common problems. */ |
| 127 | #if __USE_FORTIFY_LEVEL > 0 && defined __GNUC__ |
| 128 | # include <bits/select2.h> |
| 129 | #endif |
| 130 | |
| 131 | __END_DECLS |
| 132 | |
| 133 | #endif /* sys/select.h */ |
| 134 |