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	With the built-in tables __NR_preadv2 and __NR_pwritev2 are always defined. The kernel has never defined __NR_preadv64v2 and __NR_pwritev64v2 and is unlikely to do so, given that the preadv2 and pwritev2 system calls themselves are 64-bit. Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
		
			
				
	
	
		
			55 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			55 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* Linux implementation of preadv2 (LFS version).
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   Copyright (C) 2017-2020 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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   <https://www.gnu.org/licenses/>.  */
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#include <sys/uio.h>
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#include <sysdep-cancel.h>
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ssize_t
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preadv64v2 (int fd, const struct iovec *vector, int count, off64_t offset,
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	    int flags)
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{
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  ssize_t result = SYSCALL_CANCEL (preadv2, fd, vector, count,
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				   LO_HI_LONG (offset), flags);
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  if (result >= 0 || errno != ENOSYS)
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    return result;
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  /* Trying to emulate the preadv2 syscall flags is troublesome:
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     * We can not temporary change the file state of the O_DSYNC and O_SYNC
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       flags to emulate RWF_{D}SYNC (attempts to change the state of using
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       fcntl are silently ignored).
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     * IOCB_HIPRI requires the file opened in O_DIRECT and uses an internal
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       semantic not provided by any other flag (O_NONBLOCK for instance).  */
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  if (flags != 0)
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    {
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      __set_errno (ENOTSUP);
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      return -1;
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    }
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  if (offset == -1)
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    return __readv (fd, vector, count);
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  else
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    return preadv64 (fd, vector, count, offset);
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}
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#ifdef __OFF_T_MATCHES_OFF64_T
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strong_alias (preadv64v2, preadv2)
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#endif
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