xref: /llvm-project/libc/include/llvm-libc-macros/sys-select-macros.h (revision 330793c91d08e6ac60334e4813746db898b9407e)
1be4e4257SSiva Chandra Reddy //===-- Macros defined in sys/select.h header file ------------------------===//
2be4e4257SSiva Chandra Reddy //
3be4e4257SSiva Chandra Reddy // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4be4e4257SSiva Chandra Reddy // See https://llvm.org/LICENSE.txt for license information.
5be4e4257SSiva Chandra Reddy // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6be4e4257SSiva Chandra Reddy //
7be4e4257SSiva Chandra Reddy //===----------------------------------------------------------------------===//
8be4e4257SSiva Chandra Reddy 
9*330793c9SNick Desaulniers #ifndef LLVM_LIBC_MACROS_SYS_SELECT_MACROS_H
10*330793c9SNick Desaulniers #define LLVM_LIBC_MACROS_SYS_SELECT_MACROS_H
11be4e4257SSiva Chandra Reddy 
12be4e4257SSiva Chandra Reddy #define FD_SETSIZE 1024
13be4e4257SSiva Chandra Reddy #define __FD_SET_WORD_TYPE unsigned long
14be4e4257SSiva Chandra Reddy #define __FD_SET_WORD_SIZE (sizeof(__FD_SET_WORD_TYPE) * 8)
15be4e4257SSiva Chandra Reddy #define __FD_SET_ARRAYSIZE (FD_SETSIZE / __FD_SET_WORD_SIZE)
16be4e4257SSiva Chandra Reddy 
17be4e4257SSiva Chandra Reddy #define FD_ZERO(set)                                                           \
18be4e4257SSiva Chandra Reddy   do {                                                                         \
19be4e4257SSiva Chandra Reddy     unsigned i;                                                                \
20be4e4257SSiva Chandra Reddy     for (i = 0; i < __FD_SET_ARRAYSIZE; ++i)                                   \
21be4e4257SSiva Chandra Reddy       (set)->__set[i] = 0;                                                     \
22be4e4257SSiva Chandra Reddy   } while (0)
23be4e4257SSiva Chandra Reddy 
24be4e4257SSiva Chandra Reddy #define __FD_WORD(fd) ((fd) / __FD_SET_WORD_SIZE)
25be4e4257SSiva Chandra Reddy #define __FD_MASK(fd)                                                          \
26be4e4257SSiva Chandra Reddy   ((__FD_SET_WORD_TYPE)1) << ((__FD_SET_WORD_TYPE)((fd) % __FD_SET_WORD_SIZE))
27be4e4257SSiva Chandra Reddy 
28be4e4257SSiva Chandra Reddy #define FD_CLR(fd, set) (void)((set)->__set[__FD_WORD(fd)] &= ~__FD_MASK(fd))
29be4e4257SSiva Chandra Reddy 
30be4e4257SSiva Chandra Reddy #define FD_SET(fd, set) (void)((set)->__set[__FD_WORD(fd)] |= __FD_MASK(fd))
31be4e4257SSiva Chandra Reddy 
32be4e4257SSiva Chandra Reddy #define FD_ISSET(fd, set)                                                      \
33be4e4257SSiva Chandra Reddy   (int)(((set)->__set[__FD_WORD(fd)] & __FD_MASK(fd)) != 0)
34be4e4257SSiva Chandra Reddy 
35*330793c9SNick Desaulniers #endif // LLVM_LIBC_MACROS_SYS_SELECT_MACROS_H
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