1 /* Return reference offset represented by attribute.
2 Copyright (C) 2003 Red Hat, Inc.
3 Written by Ulrich Drepper <drepper@redhat.com>, 2003.
4
5 This program is Open Source software; you can redistribute it and/or
6 modify it under the terms of the Open Software License version 1.0 as
7 published by the Open Source Initiative.
8
9 You should have received a copy of the Open Software License along
10 with this program; if not, you may obtain a copy of the Open Software
11 License version 1.0 from http://www.opensource.org/licenses/osl.php or
12 by writing the Open Source Initiative c/o Lawrence Rosen, Esq.,
13 3001 King Ranch Road, Ukiah, CA 95482. */
14
15 #ifdef HAVE_CONFIG_H
16 # include <config.h>
17 #endif
18
19 #include <dwarf.h>
20 #include "libdwP.h"
21
22
23 int
dwarf_formref(attr,return_offset)24 dwarf_formref (attr, return_offset)
25 Dwarf_Attribute *attr;
26 Dwarf_Off *return_offset;
27 {
28 if (attr == NULL)
29 return -1;
30
31 unsigned int u128;
32 unsigned char *datap;
33
34 switch (attr->form)
35 {
36 case DW_FORM_ref1:
37 *return_offset = *attr->valp;
38 break;
39
40 case DW_FORM_ref2:
41 *return_offset = read_2ubyte_unaligned (attr->cu->dbg, attr->valp);
42 break;
43
44 case DW_FORM_ref4:
45 *return_offset = read_4ubyte_unaligned (attr->cu->dbg, attr->valp);
46 break;
47
48 case DW_FORM_ref8:
49 *return_offset = read_8ubyte_unaligned (attr->cu->dbg, attr->valp);
50 break;
51
52 case DW_FORM_ref_udata:
53 datap = attr->valp;
54 get_uleb128 (u128, datap);
55 *return_offset = u128;
56 break;
57
58 case DW_FORM_ref_addr:
59 __libdw_seterrno (DWARF_E_INVALID_REFERENCE);
60 return -1;
61
62 default:
63 __libdw_seterrno (DWARF_E_NO_REFERENCE);
64 return -1;
65 }
66
67 return 0;
68 }
69