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      1 /* Update symbol information in symbol table at the given index.
      2    Copyright (C) 2000, 2001, 2002, 2005, 2009, 2014, 2015 Red Hat, Inc.
      3    This file is part of elfutils.
      4    Written by Ulrich Drepper <drepper (at) redhat.com>, 2000.
      5 
      6    This file is free software; you can redistribute it and/or modify
      7    it under the terms of either
      8 
      9      * the GNU Lesser General Public License as published by the Free
     10        Software Foundation; either version 3 of the License, or (at
     11        your option) any later version
     12 
     13    or
     14 
     15      * the GNU General Public License as published by the Free
     16        Software Foundation; either version 2 of the License, or (at
     17        your option) any later version
     18 
     19    or both in parallel, as here.
     20 
     21    elfutils is distributed in the hope that it will be useful, but
     22    WITHOUT ANY WARRANTY; without even the implied warranty of
     23    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     24    General Public License for more details.
     25 
     26    You should have received copies of the GNU General Public License and
     27    the GNU Lesser General Public License along with this program.  If
     28    not, see <http://www.gnu.org/licenses/>.  */
     29 
     30 #ifdef HAVE_CONFIG_H
     31 # include <config.h>
     32 #endif
     33 
     34 #include <gelf.h>
     35 #include <stdlib.h>
     36 #include <string.h>
     37 
     38 #include "libelfP.h"
     39 
     40 
     41 int
     42 gelf_update_sym (Elf_Data *data, int ndx, GElf_Sym *src)
     43 {
     44   Elf_Data_Scn *data_scn = (Elf_Data_Scn *) data;
     45   Elf_Scn *scn;
     46   int result = 0;
     47 
     48   if (data == NULL)
     49     return 0;
     50 
     51   if (unlikely (data_scn->d.d_type != ELF_T_SYM))
     52     {
     53       /* The type of the data better should match.  */
     54       __libelf_seterrno (ELF_E_DATA_MISMATCH);
     55       return 0;
     56     }
     57 
     58   scn = data_scn->s;
     59   rwlock_wrlock (scn->elf->lock);
     60 
     61   if (scn->elf->class == ELFCLASS32)
     62     {
     63       Elf32_Sym *sym;
     64 
     65       /* There is the possibility that the values in the input are
     66 	 too large.  */
     67       if (unlikely (src->st_value > 0xffffffffull)
     68 	  || unlikely (src->st_size > 0xffffffffull))
     69 	{
     70 	  __libelf_seterrno (ELF_E_INVALID_DATA);
     71 	  goto out;
     72 	}
     73 
     74       /* Check whether we have to resize the data buffer.  */
     75       if (INVALID_NDX (ndx, Elf32_Sym, &data_scn->d))
     76 	{
     77 	  __libelf_seterrno (ELF_E_INVALID_INDEX);
     78 	  goto out;
     79 	}
     80 
     81       sym = &((Elf32_Sym *) data_scn->d.d_buf)[ndx];
     82 
     83 #define COPY(name) \
     84       sym->name = src->name
     85       COPY (st_name);
     86       COPY (st_value);
     87       COPY (st_size);
     88       /* Please note that we can simply copy the `st_info' element since
     89 	 the definitions of ELFxx_ST_BIND and ELFxx_ST_TYPE are the same
     90 	 for the 64 bit variant.  */
     91       COPY (st_info);
     92       COPY (st_other);
     93       COPY (st_shndx);
     94     }
     95   else
     96     {
     97       /* Check whether we have to resize the data buffer.  */
     98       if (INVALID_NDX (ndx, Elf64_Sym, &data_scn->d))
     99 	{
    100 	  __libelf_seterrno (ELF_E_INVALID_INDEX);
    101 	  goto out;
    102 	}
    103 
    104       ((Elf64_Sym *) data_scn->d.d_buf)[ndx] = *src;
    105     }
    106 
    107   result = 1;
    108 
    109   /* Mark the section as modified.  */
    110   scn->flags |= ELF_F_DIRTY;
    111 
    112  out:
    113   rwlock_unlock (scn->elf->lock);
    114 
    115   return result;
    116 }
    117