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	Like already done in various other places and advised by Roland in https://lists.gnu.org/archive/html/bug-hurd/2012-04/msg00124.html
		
			
				
	
	
		
			83 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			83 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/* Copyright (C) 1991-2025 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; see the file COPYING.LIB.  If
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   not, see <https://www.gnu.org/licenses/>.  */
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#include <unistd.h>
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#include <hurd.h>
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#include <hurd/paths.h>
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#include <hurd/fd.h>
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#include <fcntl.h>
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#include <string.h>
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/* Read the contents of the symbolic link FILE_NAME relative to FD into no more
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   than LEN bytes of BUF.  The contents are not null-terminated.
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   Returns the number of characters read, or -1 for errors.  */
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ssize_t
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__readlinkat (int fd, const char *file_name, char *buf, size_t len)
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{
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  error_t err;
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  file_t file_stat;
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  struct stat64 st;
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  enum retry_type doretry;
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  string_t retryname;
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  file_t file;
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  char *rbuf = buf;
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  mach_msg_type_number_t nread = len;
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  file_stat = __file_name_lookup_at (fd, 0, file_name, O_NOLINK, 0);
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  if (file_stat == MACH_PORT_NULL)
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    return -1;
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  err = __io_stat (file_stat, &st);
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  if (err)
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    goto out;
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  if (!S_ISLNK (st.st_mode))
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    {
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      err = EINVAL;
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      goto out;
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    }
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  err = __dir_lookup (file_stat, "", O_READ | O_NOLINK,
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                      0, &doretry, retryname, &file);
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  if (err)
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    goto out;
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  if (doretry != FS_RETRY_NORMAL || retryname[0] != '\0')
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    {
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      err = EGRATUITOUS;
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      goto out;
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    }
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  err = __io_read (file, &rbuf, &nread, 0, len);
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  __mach_port_deallocate (__mach_task_self (), file);
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  if (err)
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    goto out;
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  len = nread;
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  if (rbuf != buf)
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    {
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      memcpy (buf, rbuf, len);
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      __vm_deallocate (__mach_task_self (), (vm_address_t) rbuf, nread);
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    }
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 out:
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  __mach_port_deallocate (__mach_task_self (), file_stat);
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  return err ? __hurd_fail (err) : len;
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}
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weak_alias (__readlinkat, readlinkat)
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libc_hidden_def (readlinkat)
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