libc/include/llvm-libc-macros/sys-select-macros.h

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