Subversion Repositories openrisc_2011-10-31

/* Locate the shared object symbol nearest a given address.

   Copyright (C) 1996-2000, 2001 Free Software Foundation, Inc.

   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

   Lesser 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; if not, write to the Free

   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA

   02111-1307 USA.  */

#include <dlfcn.h>

#include <stddef.h>

#include <ldsodefs.h>

int

internal_function

_dl_addr (const void *address, Dl_info *info)

{

  const ElfW(Addr) addr = DL_LOOKUP_ADDRESS (address);

  struct link_map *l, *match;

  const ElfW(Sym) *symtab, *matchsym;

  const char *strtab;

  ElfW(Word) strtabsize;

  /* Find the highest-addressed object that ADDRESS is not below.  */

  match = NULL;

  for (l = _dl_loaded; l; l = l->l_next)

    if (addr >= l->l_map_start && addr < l->l_map_end)

      {

        /* We know ADDRESS lies within L if in any shared object.

           Make sure it isn't past the end of L's segments.  */

        size_t n = l->l_phnum;

        if (n > 0)

          {

            do

              --n;

            while (l->l_phdr[n].p_type != PT_LOAD);

            if (addr >= (l->l_addr +

                         l->l_phdr[n].p_vaddr + l->l_phdr[n].p_memsz))

              /* Off the end of the highest-addressed shared object.  */

              continue;

          }

        match = l;

        break;

      }

  if (match == NULL)

    return 0;

  /* Now we know what object the address lies in.  */

  info->dli_fname = match->l_name;

  info->dli_fbase = (void *) match->l_addr;

  /* If this is the main program the information is incomplete.  */

  if (__builtin_expect (info->dli_fbase == NULL, 0))

    {

      info->dli_fname = _dl_argv[0];

      info->dli_fbase = (void *) match->l_map_start;

    }

  symtab = (const void *) D_PTR (match, l_info[DT_SYMTAB]);

  strtab = (const void *) D_PTR (match, l_info[DT_STRTAB]);

  strtabsize = match->l_info[DT_STRSZ]->d_un.d_val;

  /* We assume that the string table follows the symbol table, because

     there is no way in ELF to know the size of the dynamic symbol table!!  */

  for (matchsym = NULL; (void *) symtab < (void *) strtab; ++symtab)

    if (addr >= match->l_addr + symtab->st_value

        && ((symtab->st_size == 0 && addr == match->l_addr + symtab->st_value)

            || addr < match->l_addr + symtab->st_value + symtab->st_size)

        && symtab->st_name < strtabsize

        && (matchsym == NULL || matchsym->st_value < symtab->st_value)

        && (ELFW(ST_BIND) (symtab->st_info) == STB_GLOBAL

            || ELFW(ST_BIND) (symtab->st_info) == STB_WEAK))

      matchsym = symtab;

  if (matchsym)

    {

      /* We found a symbol close by.  Fill in its name and exact address.  */

      info->dli_sname = strtab + matchsym->st_name;

      info->dli_saddr = (void *) (match->l_addr + matchsym->st_value);

    }

  else

    {

      /* No symbol matches.  We return only the containing object.  */

      info->dli_sname = NULL;

      info->dli_saddr = NULL;

    }

  return 1;

}