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/* SPDX-License-Identifier: LGPL-2.1 OR MIT */
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#include "../nolibc.h"
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#ifndef _NOLIBC_SYS_SELECT_H
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#define _NOLIBC_SYS_SELECT_H
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#include <linux/time.h>
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#include <linux/unistd.h>
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/* commonly an fd_set represents 256 FDs */
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#ifndef FD_SETSIZE
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#define FD_SETSIZE     256
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#endif
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#define FD_SETIDXMASK (8 * sizeof(unsigned long))
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#define FD_SETBITMASK (8 * sizeof(unsigned long)-1)
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/* for select() */
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typedef struct {
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	unsigned long fds[(FD_SETSIZE + FD_SETBITMASK) / FD_SETIDXMASK];
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} fd_set;
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#define FD_CLR(fd, set) do {						\
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		fd_set *__set = (set);					\
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		int __fd = (fd);					\
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		if (__fd >= 0)						\
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			__set->fds[__fd / FD_SETIDXMASK] &=		\
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				~(1U << (__fd & FD_SETBITMASK));	\
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	} while (0)
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#define FD_SET(fd, set) do {						\
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		fd_set *__set = (set);					\
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		int __fd = (fd);					\
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		if (__fd >= 0)						\
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			__set->fds[__fd / FD_SETIDXMASK] |=		\
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				1 << (__fd & FD_SETBITMASK);		\
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	} while (0)
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#define FD_ISSET(fd, set) ({						\
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			fd_set *__set = (set);				\
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			int __fd = (fd);				\
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		int __r = 0;						\
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		if (__fd >= 0)						\
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			__r = !!(__set->fds[__fd / FD_SETIDXMASK] &	\
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1U << (__fd & FD_SETBITMASK));						\
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		__r;							\
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	})
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#define FD_ZERO(set) do {						\
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		fd_set *__set = (set);					\
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		int __idx;						\
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		int __size = (FD_SETSIZE+FD_SETBITMASK) / FD_SETIDXMASK;\
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		for (__idx = 0; __idx < __size; __idx++)		\
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			__set->fds[__idx] = 0;				\
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	} while (0)
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/*
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 * int select(int nfds, fd_set *read_fds, fd_set *write_fds,
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 *            fd_set *except_fds, struct timeval *timeout);
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 */
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static __attribute__((unused))
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int sys_select(int nfds, fd_set *rfds, fd_set *wfds, fd_set *efds, struct timeval *timeout)
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{
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#if defined(__NR_pselect6_time64)
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	struct __kernel_timespec t;
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	if (timeout) {
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		t.tv_sec  = timeout->tv_sec;
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		t.tv_nsec = (uint32_t)timeout->tv_usec * 1000;
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	}
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	return my_syscall6(__NR_pselect6_time64, nfds, rfds, wfds, efds, timeout ? &t : NULL, NULL);
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#else
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	struct __kernel_old_timespec t;
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	if (timeout) {
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		t.tv_sec  = timeout->tv_sec;
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		t.tv_nsec = (uint32_t)timeout->tv_usec * 1000;
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	}
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	return my_syscall6(__NR_pselect6, nfds, rfds, wfds, efds, timeout ? &t : NULL, NULL);
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#endif
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}
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static __attribute__((unused))
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int select(int nfds, fd_set *rfds, fd_set *wfds, fd_set *efds, struct timeval *timeout)
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{
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	return __sysret(sys_select(nfds, rfds, wfds, efds, timeout));
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}
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#endif /* _NOLIBC_SYS_SELECT_H */
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