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			82 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			82 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* Find path of executable.
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|    Copyright (C) 1998-2016 Free Software Foundation, Inc.
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|    This file is part of the GNU C Library.
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|    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
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| 
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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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| 
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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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| 
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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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| 
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| #include <assert.h>
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| #include <stdlib.h>
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| #include <string.h>
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| #include <unistd.h>
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| #include <fcntl.h>
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| #include <sys/param.h>
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| #include <ldsodefs.h>
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| #include <sysdep.h>
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| 
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| #include <dl-dst.h>
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| 
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| /* On Linux >= 2.1 systems which have the dcache implementation we can get
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|    the path of the application from the /proc/self/exe symlink.  Try this
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|    first and fall back on the generic method if necessary.  */
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| 
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| const char *
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| _dl_get_origin (void)
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| {
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|   char linkval[PATH_MAX];
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|   char *result;
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|   int len;
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|   INTERNAL_SYSCALL_DECL (err);
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| 
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|   len = INTERNAL_SYSCALL (readlinkat, err, 4, AT_FDCWD, "/proc/self/exe",
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|                           linkval, sizeof (linkval));
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|   if (! INTERNAL_SYSCALL_ERROR_P (len, err) && len > 0 && linkval[0] != '[')
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|     {
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|       /* We can use this value.  */
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|       assert (linkval[0] == '/');
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|       while (len > 1 && linkval[len - 1] != '/')
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| 	--len;
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|       result = (char *) malloc (len + 1);
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|       if (result == NULL)
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| 	result = (char *) -1;
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|       else if (len == 1)
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| 	memcpy (result, "/", 2);
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|       else
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| 	*((char *) __mempcpy (result, linkval, len - 1)) = '\0';
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|     }
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|   else
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|     {
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|       result = (char *) -1;
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|       /* We use the environment variable LD_ORIGIN_PATH.  If it is set make
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| 	 a copy and strip out trailing slashes.  */
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|       if (GLRO(dl_origin_path) != NULL)
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| 	{
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| 	  size_t len = strlen (GLRO(dl_origin_path));
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| 	  result = (char *) malloc (len + 1);
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| 	  if (result == NULL)
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| 	    result = (char *) -1;
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| 	  else
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| 	    {
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| 	      char *cp = __mempcpy (result, GLRO(dl_origin_path), len);
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| 	      while (cp > result + 1 && cp[-1] == '/')
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| 		--cp;
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| 	      *cp = '\0';
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| 	    }
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| 	}
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|     }
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| 
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|   return result;
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| }
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