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	This patch consolidates the select Linux syscall implementation on
sysdeps/unix/sysv/linux/select.c.  The changes are:
  1. Remove select from auto-generation syscalls.list on the architecture
     that uses __NR_select.
  2. Remove generic implementation add a default one that handle all
     current cases (with the expection of alpha)
     The new default implementation will either use __NR_select if
     available of fallback to __NR_pselect6 otherwise.
  3. Add a alpha outlier implementation which requires old compatibility
     symbols.
Checked on i686-linux-gnu, x86_64-linux-gnu, x86_64-linux-gnux32,
arch64-linux-gnu, arm-linux-gnueabihf, and powerpc64le-linux-gnu.
	* sysdeps/unix/sysv/linux/alpha/Makefile (sysdep_routines): Add
	osf_select.
	* sysdeps/unix/sysv/linux/alpha/select.c: New file.
	* sysdeps/unix/sysv/linux/alpha/syscalls.list: Remove select and
	osf_select from auto-generation list.
	* sysdeps/unix/sysv/linux/syscalls.list: Likewise.
	* sysdeps/unix/sysv/linux/sparc/sparc64/syscalls.list: Likewise.
	* sysdeps/unix/sysv/linux/generic/select.c: Remove file.
	* sysdeps/unix/sysv/linux/select.c: New file.
		
	
		
			
				
	
	
		
			72 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			72 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* Linux select implementation.
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   Copyright (C) 2017 Free Software Foundation, Inc.
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   This file is part of the GNU C Library.
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   The GNU C Library is free software; you can redistribute it and/or
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   modify it under the terms of the GNU Lesser General Public
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   License as published by the Free Software Foundation; either
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   version 2.1 of the License, or (at your option) any later version.
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   The GNU C Library is distributed in the hope that it will be useful,
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   but WITHOUT ANY WARRANTY; without even the implied warranty of
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   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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   Lesser General Public License for more details.
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   You should have received a copy of the GNU Lesser General Public
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   License along with the GNU C Library.  If not, see
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   <http://www.gnu.org/licenses/>.  */
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#include <sys/time.h>
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#include <sys/types.h>
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#include <sys/select.h>
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#include <errno.h>
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#include <sysdep-cancel.h>
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/* Check the first NFDS descriptors each in READFDS (if not NULL) for read
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   readiness, in WRITEFDS (if not NULL) for write readiness, and in EXCEPTFDS
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   (if not NULL) for exceptional conditions.  If TIMEOUT is not NULL, time out
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   after waiting the interval specified therein.  Returns the number of ready
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   descriptors, or -1 for errors.  */
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#ifdef __NR__newselect
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# undef __NR_select
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# define __NR_select __NR__newselect
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#endif
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int
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__select (int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
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	  struct timeval *timeout)
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{
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#ifdef __NR_select
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  return SYSCALL_CANCEL (select, nfds, readfds, writefds, exceptfds,
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			 timeout);
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#else
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  int result;
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  struct timespec ts, *tsp = NULL;
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  if (timeout)
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    {
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      TIMEVAL_TO_TIMESPEC (timeout, &ts);
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      tsp = &ts;
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    }
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  result = SYSCALL_CANCEL (pselect6, nfds, readfds, writefds, exceptfds, tsp,
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			   NULL);
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  if (timeout)
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    {
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      /* Linux by default will update the timeout after a pselect6 syscall
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         (though the pselect() glibc call suppresses this behavior).
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         Since select() on Linux has the same behavior as the pselect6
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         syscall, we update the timeout here.  */
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      TIMESPEC_TO_TIMEVAL (timeout, &ts);
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    }
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  return result;
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#endif
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}
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libc_hidden_def (__select)
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weak_alias (__select, select)
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weak_alias (__select, __libc_select)
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