Line data    Source code

       1             : /* Conversion functions for versioning information.
       2             :    Copyright (C) 2006, 2007 Red Hat, Inc.
       3             :    This file is part of elfutils.
       4             :    Written by Ulrich Drepper <drepper@redhat.com>, 2006.
       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             : #include <assert.h>
      31             : #include <gelf.h>
      32             : 
      33             : #include "libelfP.h"
      34             : 
      35             : 
      36             : static void
      37          41 : elf_cvt_gnuhash (void *dest, const void *src, size_t len, int encode)
      38             : {
      39             :   /* The GNU hash table format on 64 bit machines mixes 32 bit and 64 bit
      40             :      words.  We must detangle them here.   */
      41          41 :   Elf32_Word *dest32 = dest;
      42          41 :   const Elf32_Word *src32 = src;
      43             : 
      44             :   /* First four control words, 32 bits.  */
      45         205 :   for (unsigned int cnt = 0; cnt < 4; ++cnt)
      46             :     {
      47         164 :       if (len < 4)
      48             :         return;
      49         164 :       dest32[cnt] = bswap_32 (src32[cnt]);
      50         164 :       len -= 4;
      51             :     }
      52             : 
      53          41 :   Elf32_Word bitmask_words = encode ? src32[2] : dest32[2];
      54             : 
      55             :   /* Now the 64 bit words.  */
      56          41 :   Elf64_Xword *dest64 = (Elf64_Xword *) &dest32[4];
      57          41 :   const Elf64_Xword *src64 = (const Elf64_Xword *) &src32[4];
      58          82 :   for (unsigned int cnt = 0; cnt < bitmask_words; ++cnt)
      59             :     {
      60          41 :       if (len < 8)
      61             :         return;
      62          41 :       dest64[cnt] = bswap_64 (src64[cnt]);
      63          41 :       len -= 8;
      64             :     }
      65             : 
      66             :   /* The rest are 32 bit words again.  */
      67          41 :   src32 = (const Elf32_Word *) &src64[bitmask_words];
      68          41 :   dest32 = (Elf32_Word *) &dest64[bitmask_words];
      69          93 :   while (len >= 4)
      70             :     {
      71          52 :       *dest32++ = bswap_32 (*src32++);
      72          52 :       len -= 4;
      73             :     }
      74             : }