Line data    Source code

       1             : /* Iterate through modules.
       2             :    Copyright (C) 2005, 2008 Red Hat, Inc.
       3             :    This file is part of elfutils.
       4             : 
       5             :    This file is free software; you can redistribute it and/or modify
       6             :    it under the terms of either
       7             : 
       8             :      * the GNU Lesser General Public License as published by the Free
       9             :        Software Foundation; either version 3 of the License, or (at
      10             :        your option) any later version
      11             : 
      12             :    or
      13             : 
      14             :      * the GNU General Public License as published by the Free
      15             :        Software Foundation; either version 2 of the License, or (at
      16             :        your option) any later version
      17             : 
      18             :    or both in parallel, as here.
      19             : 
      20             :    elfutils is distributed in the hope that it will be useful, but
      21             :    WITHOUT ANY WARRANTY; without even the implied warranty of
      22             :    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      23             :    General Public License for more details.
      24             : 
      25             :    You should have received copies of the GNU General Public License and
      26             :    the GNU Lesser General Public License along with this program.  If
      27             :    not, see <http://www.gnu.org/licenses/>.  */
      28             : 
      29             : #ifdef HAVE_CONFIG_H
      30             : # include <config.h>
      31             : #endif
      32             : 
      33             : #include "libdwflP.h"
      34             : 
      35             : ptrdiff_t
      36         792 : dwfl_getmodules (Dwfl *dwfl,
      37             :                  int (*callback) (Dwfl_Module *, void **,
      38             :                                   const char *, Dwarf_Addr, void *),
      39             :                  void *arg,
      40             :                  ptrdiff_t offset)
      41             : {
      42         792 :   if (dwfl == NULL)
      43             :     return -1;
      44             : 
      45             :   /* We iterate through the linked list when it's all we have.
      46             :      But continuing from an offset is slow that way.  So when
      47             :      DWFL->lookup_module is populated, we can instead keep our
      48             :      place by jumping directly into the array.  Since the actions
      49             :      of a callback could cause it to get populated, we must
      50             :      choose the style of place-holder when we return an offset,
      51             :      and we encode the choice in the low bits of that value.  */
      52             : 
      53         792 :   Dwfl_Module *m = dwfl->modulelist;
      54             : 
      55         792 :   if ((offset & 3) == 1)
      56             :     {
      57          17 :       offset >>= 2;
      58          68 :       for (ptrdiff_t pos = 0; pos < offset; ++pos)
      59          51 :         if (m == NULL)
      60             :           return -1;
      61             :         else
      62          51 :           m = m->next;
      63             :     }
      64         775 :   else if (((offset & 3) == 2) && likely (dwfl->lookup_module != NULL))
      65             :     {
      66           0 :       offset >>= 2;
      67             : 
      68           0 :       if ((size_t) offset - 1 == dwfl->lookup_elts)
      69             :         return 0;
      70             : 
      71           0 :       if (unlikely ((size_t) offset - 1 > dwfl->lookup_elts))
      72             :         return -1;
      73             : 
      74           0 :       m = dwfl->lookup_module[offset - 1];
      75           0 :       if (unlikely (m == NULL))
      76             :         return -1;
      77             :     }
      78         775 :   else if (offset != 0)
      79             :     {
      80           0 :       __libdwfl_seterrno (DWFL_E_BADSTROFF);
      81           0 :       return -1;
      82             :     }
      83             : 
      84        1543 :   while (m != NULL)
      85             :     {
      86         826 :       int ok = (*callback) (MODCB_ARGS (m), arg);
      87         826 :       ++offset;
      88         826 :       m = m->next;
      89         826 :       if (ok != DWARF_CB_OK)
      90         126 :         return ((dwfl->lookup_module == NULL) ? ((offset << 2) | 1)
      91          99 :                 : (((m == NULL ? (ptrdiff_t) dwfl->lookup_elts + 1
      92          24 :                      : m->segment + 1) << 2) | 2));
      93             :     }
      94             :   return 0;
      95             : }
      96             : INTDEF (dwfl_getmodules)