Line data    Source code

       1             : /* Find line information for address.
       2             :    Copyright (C) 2004, 2005, 2014 Red Hat, Inc.
       3             :    This file is part of elfutils.
       4             :    Written by Ulrich Drepper <drepper@redhat.com>, 2004.
       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 "libdwP.h"
      35             : #include <assert.h>
      36             : 
      37             : 
      38             : Dwarf_Line *
      39          16 : dwarf_getsrc_die (Dwarf_Die *cudie, Dwarf_Addr addr)
      40             : {
      41             :   Dwarf_Lines *lines;
      42             :   size_t nlines;
      43             : 
      44          16 :   if (INTUSE(dwarf_getsrclines) (cudie, &lines, &nlines) != 0)
      45             :     return NULL;
      46             : 
      47             :   /* The lines are sorted by address, so we can use binary search.  */
      48          16 :   if (nlines > 0)
      49             :     {
      50          16 :       size_t l = 0, u = nlines - 1;
      51          91 :       while (l < u)
      52             :         {
      53          59 :           size_t idx = u - (u - l) / 2;
      54          59 :           Dwarf_Line *line = &lines->info[idx];
      55          59 :           if (addr < line->addr)
      56          28 :             u = idx - 1;
      57             :           else
      58             :             l = idx;
      59             :         }
      60             : 
      61             :       /* This is guaranteed for us by libdw read_srclines.  */
      62          16 :       assert (lines->info[nlines - 1].end_sequence);
      63             : 
      64             :       /* The last line which is less than or equal to addr is what we
      65             :          want, unless it is the end_sequence which is after the
      66             :          current line sequence.  */
      67          16 :       Dwarf_Line *line = &lines->info[l];
      68          16 :       if (! line->end_sequence && line->addr <= addr)
      69          16 :         return &lines->info[l];
      70             :     }
      71             : 
      72           0 :   __libdw_seterrno (DWARF_E_ADDR_OUTOFRANGE);
      73           0 :   return NULL;
      74             : }