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musl/include/sys/select.h

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initial check-in, version 0.5.0
2011-02-12 05:22:29 +00:00
#ifndef _SYS_SELECT_H
#define _SYS_SELECT_H
#ifdef __cplusplus
extern "C" {
#endif
remove all remaining redundant __restrict/__inline/_Noreturn defs
2012-09-08 21:14:52 +00:00
#include <features.h>
use restrict everywhere it's required by c99 and/or posix 2008 to deal with the fact that the public headers may be used with pre-c99 compilers, __restrict is used in place of restrict, and defined appropriately for any supported compiler. we also avoid the form [restrict] since older versions of gcc rejected it due to a bug in the original c99 standard, and instead use the form *restrict.
2012-09-07 02:44:55 +00:00
initial check-in, version 0.5.0
2011-02-12 05:22:29 +00:00
#define __NEED_size_t
#define __NEED_time_t
fix and cleanup suseconds_t/timeval stuff (broken on 64-bit) trash in the upper 32 bits was making the kernel sleep forever in select on 64-bit systems.
2011-04-13 17:16:49 +00:00
#define __NEED_suseconds_t
initial check-in, version 0.5.0
2011-02-12 05:22:29 +00:00
#define __NEED_struct_timeval
#define __NEED_struct_timespec
#define __NEED_sigset_t
#include <bits/alltypes.h>
#define FD_SETSIZE 1024
add useless type fd_mask. it's in the reserved namespace.
2011-04-14 20:23:31 +00:00
typedef unsigned long fd_mask;
initial check-in, version 0.5.0
2011-02-12 05:22:29 +00:00
typedef struct
{
unsigned long fds_bits[FD_SETSIZE / 8 / sizeof(long)];
} fd_set;
#define FD_ZERO(s) do { int __i; unsigned long *__b=(s)->fds_bits; for(__i=sizeof (fd_set)/sizeof (long); __i; __i--) *__b++=0; } while(0)
fix broken FD_* macros on 64-bit targets 1 is too small if int is 32-bit but unsigned long is 64-bit. be explicit and use 1UL.
2011-08-27 23:42:13 +00:00
#define FD_SET(d, s) ((s)->fds_bits[(d)/(8*sizeof(long))] |= (1UL<<((d)%(8*sizeof(long)))))
#define FD_CLR(d, s) ((s)->fds_bits[(d)/(8*sizeof(long))] &= ~(1UL<<((d)%(8*sizeof(long)))))
FD_ISSET must return an int. this is the easiest way. casting to int would not be correct because high bits could be lost. mapping the high bits down onto low bits would be costlier in the common case where the result is just used in a conditional. changing the type of the bit array elements to int would permute the order of the bit array on 64-bit big endian systems, so that's not an option either.
2011-09-24 02:24:33 +00:00
#define FD_ISSET(d, s) !!((s)->fds_bits[(d)/(8*sizeof(long))] & (1UL<<((d)%(8*sizeof(long)))))
initial check-in, version 0.5.0
2011-02-12 05:22:29 +00:00
use restrict everywhere it's required by c99 and/or posix 2008 to deal with the fact that the public headers may be used with pre-c99 compilers, __restrict is used in place of restrict, and defined appropriately for any supported compiler. we also avoid the form [restrict] since older versions of gcc rejected it due to a bug in the original c99 standard, and instead use the form *restrict.
2012-09-07 02:44:55 +00:00
int select (int, fd_set *__restrict, fd_set *__restrict, fd_set *__restrict, struct timeval *__restrict);
int pselect (int, fd_set *__restrict, fd_set *__restrict, fd_set *__restrict, const struct timespec *__restrict, const sigset_t *__restrict);
initial check-in, version 0.5.0
2011-02-12 05:22:29 +00:00
add NFDBITS in sys/select.h with appropriate feature tests the main use for this macro seems to be knowing the correct allocation granularity for dynamic-sized fd_set objects. such usage is non-conforming and results in undefined behavior, but it is widespread in applications.
2013-07-06 05:12:28 +00:00
#if defined(_GNU_SOURCE) || defined(_BSD_SOURCE)
#define NFDBITS (8*(int)sizeof(long))
#endif
initial check-in, version 0.5.0
2011-02-12 05:22:29 +00:00
#ifdef __cplusplus
}
#endif
#endif