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      1 /* Return program header table entry.
      2    Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
      3    Written by Ulrich Drepper <drepper (at) redhat.com>, 1998.
      4 
      5    This program is free software; you can redistribute it and/or modify
      6    it under the terms of the GNU General Public License as published by
      7    the Free Software Foundation, version 2.
      8 
      9    This program is distributed in the hope that it will be useful,
     10    but WITHOUT ANY WARRANTY; without even the implied warranty of
     11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     12    GNU General Public License for more details.
     13 
     14    You should have received a copy of the GNU General Public License
     15    along with this program; if not, write to the Free Software Foundation,
     16    Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
     17 
     18 #ifdef HAVE_CONFIG_H
     19 # include <config.h>
     20 #endif
     21 
     22 #include <gelf.h>
     23 #include <string.h>
     24 
     25 #include "libelfP.h"
     26 
     27 
     28 GElf_Phdr *
     29 gelf_getphdr (elf, ndx, dst)
     30      Elf *elf;
     31      int ndx;
     32      GElf_Phdr *dst;
     33 {
     34   GElf_Phdr *result = NULL;
     35 
     36   if (elf == NULL)
     37     return NULL;
     38 
     39   if (unlikely (elf->kind != ELF_K_ELF))
     40     {
     41       __libelf_seterrno (ELF_E_INVALID_HANDLE);
     42       return NULL;
     43     }
     44 
     45   if (dst == NULL)
     46     {
     47       __libelf_seterrno (ELF_E_INVALID_OPERAND);
     48       return NULL;
     49     }
     50 
     51   rwlock_rdlock (elf->lock);
     52 
     53   if (elf->class == ELFCLASS32)
     54     {
     55       /* Copy the elements one-by-one.  */
     56       Elf32_Phdr *phdr = elf->state.elf32.phdr;
     57 
     58       if (phdr == NULL)
     59 	{
     60 	  phdr = INTUSE(elf32_getphdr) (elf);
     61 	  if (phdr == NULL)
     62 	    /* The error number is already set.  */
     63 	    goto out;
     64 	}
     65 
     66       /* Test whether the index is ok.  */
     67       if (ndx >= elf->state.elf32.ehdr->e_phnum)
     68 	{
     69 	  __libelf_seterrno (ELF_E_INVALID_INDEX);
     70 	  goto out;
     71 	}
     72 
     73       /* We know the result now.  */
     74       result = dst;
     75 
     76       /* Now correct the pointer to point to the correct element.  */
     77       phdr += ndx;
     78 
     79 #define COPY(Name) result->Name = phdr->Name
     80       COPY (p_type);
     81       COPY (p_offset);
     82       COPY (p_vaddr);
     83       COPY (p_paddr);
     84       COPY (p_filesz);
     85       COPY (p_memsz);
     86       COPY (p_flags);
     87       COPY (p_align);
     88     }
     89   else
     90     {
     91       /* Copy the elements one-by-one.  */
     92       Elf64_Phdr *phdr = elf->state.elf64.phdr;
     93 
     94       if (phdr == NULL)
     95 	{
     96 	  phdr = INTUSE(elf64_getphdr) (elf);
     97 	  if (phdr == NULL)
     98 	    /* The error number is already set.  */
     99 	    goto out;
    100 	}
    101 
    102       /* Test whether the index is ok.  */
    103       if (ndx >= elf->state.elf64.ehdr->e_phnum)
    104 	{
    105 	  __libelf_seterrno (ELF_E_INVALID_INDEX);
    106 	  goto out;
    107 	}
    108 
    109       /* We only have to copy the data.  */
    110       result = memcpy (dst, phdr + ndx, sizeof (GElf_Phdr));
    111     }
    112 
    113  out:
    114   rwlock_unlock (elf->lock);
    115 
    116   return result;
    117 }
    118