1 /* Find line information for a given macro.
2 Copyright (C) 2014 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 "libdwP.h"
34
35 int
dwarf_macro_getsrcfiles(Dwarf * dbg,Dwarf_Macro * macro,Dwarf_Files ** files,size_t * nfiles)36 dwarf_macro_getsrcfiles (Dwarf *dbg, Dwarf_Macro *macro,
37 Dwarf_Files **files, size_t *nfiles)
38 {
39 if (macro == NULL)
40 return -1;
41
42 Dwarf_Macro_Op_Table *const table = macro->table;
43 if (table->files == NULL)
44 {
45 Dwarf_Off line_offset = table->line_offset;
46 if (line_offset == (Dwarf_Off) -1)
47 {
48 *files = NULL;
49 *nfiles = 0;
50 return 0;
51 }
52
53 /* If TABLE->comp_dir is NULL that could mean any of the
54 following:
55
56 - The macro unit is not bound to a CU. It's an auxiliary
57 unit used purely for import from other units. In that case
58 there's actually no COMP_DIR value that we could use.
59
60 - The macro unit is bound to a CU, but there's no
61 DW_AT_comp_dir attribute at the CU DIE.
62
63 - The macro unit is bound to a CU, but we don't know that,
64 likely because its iteration was requested through
65 dwarf_getmacros_off interface. This might be legitimate if
66 one macro unit imports another CU's macro unit, but that is
67 unlikely to happen in practice. Most probably this is not
68 legitimate use of the interfaces.
69
70 So when the interfaces are used correctly, COMP_DIR value is
71 always right. That means that we can cache the parsed
72 .debug_line unit without fear that later on someone requests
73 the same unit through dwarf_getsrcfiles, and the file names
74 will be broken. */
75
76 if (__libdw_getsrclines (dbg, line_offset, table->comp_dir,
77 table->is_64bit ? 8 : 4,
78 NULL, &table->files) < 0)
79 table->files = (void *) -1;
80 }
81
82 if (table->files == (void *) -1)
83 return -1;
84
85 *files = table->files;
86 *nfiles = table->files->nfiles;
87 return 0;
88 }
89