Line data    Source code

       1             : /* Get function information.
       2             :    Copyright (C) 2005, 2013, 2015 Red Hat, Inc.
       3             :    This file is part of elfutils.
       4             :    Written by Ulrich Drepper <drepper@redhat.com>, 2005.
       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 <dwarf.h>
      35             : #include "libdwP.h"
      36             : 
      37             : 
      38             : struct visitor_info
      39             : {
      40             :   /* The user callback of dwarf_getfuncs.  */
      41             :   int (*callback) (Dwarf_Die *, void *);
      42             : 
      43             :   /* The user arg value to dwarf_getfuncs.  */
      44             :   void *arg;
      45             : 
      46             :   /* Addr of the DIE offset where to (re)start the search.  Zero for all.  */
      47             :   void *start_addr;
      48             : 
      49             :   /* Last subprogram DIE addr seen.  */
      50             :   void *last_addr;
      51             : 
      52             :   /* The CU only contains C functions.  Allows pruning of most subtrees.  */
      53             :   bool c_cu;
      54             : };
      55             : 
      56             : static int
      57     1849525 : tree_visitor (unsigned int depth __attribute__ ((unused)),
      58             :               struct Dwarf_Die_Chain *chain, void *arg)
      59             : {
      60     1849525 :   struct visitor_info *const v = arg;
      61     1849525 :   Dwarf_Die *die = &chain->die;
      62     1849525 :   void *start_addr = v->start_addr;
      63     1849525 :   void *die_addr = die->addr;
      64             : 
      65             :   /* Pure C CUs can only contain defining subprogram DIEs as direct
      66             :      children of the CU DIE or as nested function inside a normal C
      67             :      code constructs.  */
      68     1849525 :   int tag = INTUSE(dwarf_tag) (die);
      69     1849525 :   if (v->c_cu
      70     1842389 :       && tag != DW_TAG_subprogram
      71     1842389 :       && tag != DW_TAG_lexical_block
      72     1751387 :       && tag != DW_TAG_inlined_subroutine)
      73             :     {
      74     1725372 :       chain->prune = true;
      75     1725372 :       return DWARF_CB_OK;
      76             :     }
      77             : 
      78             :   /* Skip all DIEs till we found the (re)start addr.  */
      79      124153 :   if (start_addr != NULL)
      80             :     {
      81         115 :       if (die_addr == start_addr)
      82          40 :         v->start_addr = NULL;
      83         115 :       return DWARF_CB_OK;
      84             :     }
      85             : 
      86             :   /* If this isn't a (defining) subprogram entity, skip DIE.  */
      87      124038 :   if (tag != DW_TAG_subprogram
      88       47779 :       || INTUSE(dwarf_hasattr) (die, DW_AT_declaration))
      89      100675 :     return DWARF_CB_OK;
      90             : 
      91       23363 :   v->last_addr = die_addr;
      92       23363 :   return (*v->callback) (die, v->arg);
      93             : }
      94             : 
      95             : ptrdiff_t
      96        6389 : dwarf_getfuncs (Dwarf_Die *cudie, int (*callback) (Dwarf_Die *, void *),
      97             :                 void *arg, ptrdiff_t offset)
      98             : {
      99        6389 :   if (unlikely (cudie == NULL
     100             :                 || INTUSE(dwarf_tag) (cudie) != DW_TAG_compile_unit))
     101           2 :     return -1;
     102             : 
     103        6387 :   int lang = INTUSE(dwarf_srclang) (cudie);
     104       12774 :   bool c_cu = (lang == DW_LANG_C89
     105        6387 :                || lang == DW_LANG_C
     106        6387 :                || lang == DW_LANG_C99
     107        6387 :                || lang == DW_LANG_C11);
     108             : 
     109        6387 :   struct visitor_info v = { callback, arg, (void *) offset, NULL, c_cu };
     110       12774 :   struct Dwarf_Die_Chain chain = { .die = CUDIE (cudie->cu),
     111             :                                    .parent = NULL };
     112        6387 :   int res = __libdw_visit_scopes (0, &chain, NULL, &tree_visitor, NULL, &v);
     113             : 
     114        6387 :   if (res == DWARF_CB_ABORT)
     115          40 :     return (ptrdiff_t) v.last_addr;
     116             :   else
     117        6347 :     return res;
     118             : }