uclibc-ng/libc/sysdeps/linux/frv/crtreloc.c

/* Copyright (C) 2003 Free Software Foundation, Inc.
   written by Alexandre Oliva <aoliva@redhat.com>
This file is part of the GNU C Library.

The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public License as
published by the Free Software Foundation; either version 2.1 of the
License, or (at your option) any later version.

The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
Library General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; see the file COPYING.LIB.  If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA.  */

#define _GNU_SOURCE
#include <link.h>

#include <sys/types.h>

#include <elf.h>
#include <bits/elf-fdpic.h>

/* This file is to be compiled into crt object files, to enable
   executables to easily self-relocate.  */

#define hidden __attribute__((__visibility__("hidden")))

/* Compute the runtime address of pointer in the range [p,e), and then
   map the pointer pointed by it.  */
inline static void ***
reloc_range_indirect (void ***p, void ***e,
		      const struct elf32_fdpic_loadmap *map)
{
  while (p < e)
    {
      void *ptr = __reloc_pointer (*p, map);
      if (ptr)
	{
	  void *pt;
	  if ((long)ptr & 3)
	    __builtin_memcpy(&pt, ptr, sizeof(pt));
	  else
	    pt = *(void**)ptr;
	  pt = __reloc_pointer (pt, map);
	  if ((long)ptr & 3)
	    __builtin_memcpy(ptr, &pt, sizeof(pt));
	  else
	    *(void**)ptr = pt;
	}
      p++;
    }
  return p;
}

/* Call __reloc_range_indirect for the given range except for the last
   entry, whose contents are only relocated.  It's expected to hold
   the GOT value.  */
void* hidden
__self_reloc (const struct elf32_fdpic_loadmap *map,
	      void ***p, void ***e)
{
  p = reloc_range_indirect (p, e-1, map);

  if (p >= e)
    return (void*)-1;
  
  return __reloc_pointer (*p, map);
}

#if 0
/* These are other functions that might be useful, but that we don't
   need.  */

/* Remap pointers in [p,e).  */
inline static void**
reloc_range (void **p, void **e,
	     const struct elf32_fdpic_loadmap *map)
{
  while (p < e)
    {
      *p = __reloc_pointer (*p, map);
      p++;
    }
  return p;
}

/* Remap p, adjust e by the same offset, then map the pointers in the
   range determined by them.  */
void hidden
__reloc_range (const struct elf32_fdpic_loadmap *map,
	       void **p, void **e)
{
  void **old = p;

  p = __reloc_pointer (p, map);
  e += p - old;
  reloc_range (p, e, map);
}

/* Remap p, adjust e by the same offset, then map pointers referenced
   by the (unadjusted) pointers in the range.  Return the relocated
   value of the last pointer in the range.  */
void* hidden
__reloc_range_indirect (const struct elf32_fdpic_loadmap *map,
			void ***p, void ***e)
{
  void ***old = p;

  p = __reloc_pointer (p, map);
  e += p - old;
  return reloc_range_indirect (p, e, map);
}
#endif