GDB (xrefs)

/tmp/gdb-8.1/gdb/build-id.c
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1 /* build-id-related functions.
2
3 Copyright (C) 1991-2018 Free Software Foundation, Inc.
4
5 This file is part of GDB.
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
19
20 #include "defs.h"
21 #include "bfd.h"
22 #include "gdb_bfd.h"
23 #include "build-id.h"
24 #include "gdb_vecs.h"
25 #include "symfile.h"
26 #include "objfiles.h"
27 #include "filenames.h"
28 #include "gdbcore.h"
29
30 /* See build-id.h. */
31
32 const struct bfd_build_id *
33 build_id_bfd_get (bfd *abfd)
34 {
35 if (!bfd_check_format (abfd, bfd_object))
36 return NULL;
37
38 if (abfd->build_id != NULL)
39 return abfd->build_id;
40
41 /* No build-id */
42 return NULL;
43 }
44
45 /* See build-id.h. */
46
47 int
48 build_id_verify (bfd *abfd, size_t check_len, const bfd_byte *check)
49 {
50 const struct bfd_build_id *found;
51 int retval = 0;
52
53 found = build_id_bfd_get (abfd);
54
55 if (found == NULL)
56 warning (_("File \"%s\" has no build-id, file skipped"),
57 bfd_get_filename (abfd));
58 else if (found->size != check_len
59 || memcmp (found->data, check, found->size) != 0)
60 warning (_("File \"%s\" has a different build-id, file skipped"),
61 bfd_get_filename (abfd));
62 else
63 retval = 1;
64
65 return retval;
66 }
67
68 /* See build-id.h. */
69
70 gdb_bfd_ref_ptr
71 build_id_to_debug_bfd (size_t build_id_len, const bfd_byte *build_id)
72 {
73 char *link, *debugdir;
74 VEC (char_ptr) *debugdir_vec;
75 struct cleanup *back_to;
76 int ix;
77 gdb_bfd_ref_ptr abfd;
78 int alloc_len;
79
80 /* DEBUG_FILE_DIRECTORY/.build-id/ab/cdef */
81 alloc_len = (strlen (debug_file_directory)
82 + (sizeof "/.build-id/" - 1) + 1
83 + 2 * build_id_len + (sizeof ".debug" - 1) + 1);
84 link = (char *) alloca (alloc_len);
85
86 /* Keep backward compatibility so that DEBUG_FILE_DIRECTORY being "" will
87 cause "/.build-id/..." lookups. */
88
89 debugdir_vec = dirnames_to_char_ptr_vec (debug_file_directory);
90 back_to = make_cleanup_free_char_ptr_vec (debugdir_vec);
91
92 for (ix = 0; VEC_iterate (char_ptr, debugdir_vec, ix, debugdir); ++ix)
93 {
94 size_t debugdir_len = strlen (debugdir);
95 const gdb_byte *data = build_id;
96 size_t size = build_id_len;
97 char *s;
98 char *filename = NULL;
99 struct cleanup *inner;
100
101 memcpy (link, debugdir, debugdir_len);
102 s = &link[debugdir_len];
103 s += sprintf (s, "/.build-id/");
104 if (size > 0)
105 {
106 size--;
107 s += sprintf (s, "%02x", (unsigned) *data++);
108 }
109 if (size > 0)
110 *s++ = '/';
111 while (size-- > 0)
112 s += sprintf (s, "%02x", (unsigned) *data++);
113 strcpy (s, ".debug");
114
115 if (separate_debug_file_debug)
116 printf_unfiltered (_(" Trying %s\n"), link);
117
118 /* lrealpath() is expensive even for the usually non-existent files. */
119 if (access (link, F_OK) == 0)
120 filename = lrealpath (link);
121
122 if (filename == NULL)
123 continue;
124
125 /* We expect to be silent on the non-existing files. */
126 inner = make_cleanup (xfree, filename);
127 abfd = gdb_bfd_open (filename, gnutarget, -1);
128 do_cleanups (inner);
129
130 if (abfd == NULL)
131 continue;
132
133 if (build_id_verify (abfd.get(), build_id_len, build_id))
134 break;
135
136 abfd.release ();
137 }
138
139 do_cleanups (back_to);
140 return abfd;
141 }
142
143 /* See build-id.h. */
144
145 char *
146 find_separate_debug_file_by_buildid (struct objfile *objfile)
147 {
148 const struct bfd_build_id *build_id;
149
150 build_id = build_id_bfd_get (objfile->obfd);
151 if (build_id != NULL)
152 {
153 if (separate_debug_file_debug)
154 printf_unfiltered (_("\nLooking for separate debug info (build-id) for "
155 "%s\n"), objfile_name (objfile));
156
157 gdb_bfd_ref_ptr abfd (build_id_to_debug_bfd (build_id->size,
158 build_id->data));
159 /* Prevent looping on a stripped .debug file. */
160 if (abfd != NULL
161 && filename_cmp (bfd_get_filename (abfd.get ()),
162 objfile_name (objfile)) == 0)
163 warning (_("\"%s\": separate debug info file has no debug info"),
164 bfd_get_filename (abfd.get ()));
165 else if (abfd != NULL)
166 return xstrdup (bfd_get_filename (abfd.get ()));
167 }
168 return NULL;
169 }
objfile::obfd
bfd * obfd
Definition: objfiles.h:342
find_separate_debug_file_by_buildid
char * find_separate_debug_file_by_buildid(struct objfile *objfile)
Definition: build-id.c:146
xfree
void xfree(void *)
warning
void warning(const char *fmt,...)
Definition: errors.c:26
build-id.h
VEC
#define VEC(T)
Definition: vec.h:414
cleanup
Definition: cleanups.c:38
_
#define _(String)
Definition: gdb_locale.h:35
gdb_bfd.h
defs.h
char_ptr
char * char_ptr
Definition: gdb_vecs.h:25
debug_file_directory
char * debug_file_directory
Definition: symfile.c:1414
objfiles.h
VEC_iterate
#define VEC_iterate(T, V, I, P)
Definition: vec.h:181
gdb::ref_ptr
Definition: gdb_ref_ptr.h:49
gdb_bfd_open
gdb_bfd_ref_ptr gdb_bfd_open(const char *name, const char *target, int fd)
Definition: gdb_bfd.c:383
build_id_verify
int build_id_verify(bfd *abfd, size_t check_len, const bfd_byte *check)
Definition: build-id.c:48
gnutarget
char * gnutarget
Definition: corefile.c:442
make_cleanup
struct cleanup * make_cleanup(make_cleanup_ftype *function, void *arg)
Definition: cleanups.c:116
printf_unfiltered
void printf_unfiltered(const char *format,...)
Definition: utils.c:2056
objfile_name
const char * objfile_name(const struct objfile *objfile)
Definition: objfiles.c:1557
separate_debug_file_debug
int separate_debug_file_debug
Definition: symfile.c:1333
objfile
Definition: objfiles.h:286
gdb_byte
bfd_byte gdb_byte
Definition: common-types.h:38
gdbcore.h
build_id_bfd_get
const struct bfd_build_id * build_id_bfd_get(bfd *abfd)
Definition: build-id.c:33
check
static void check(BOOL ok, const char *file, int line)
Definition: windows-nat.c:323
gdb::ref_ptr::release
T * release()
Definition: gdb_ref_ptr.h:138
gdb_vecs.h
gdb::ref_ptr::get
T * get() const
Definition: gdb_ref_ptr.h:130
build_id_to_debug_bfd
gdb_bfd_ref_ptr build_id_to_debug_bfd(size_t build_id_len, const bfd_byte *build_id)
Definition: build-id.c:71
make_cleanup_free_char_ptr_vec
struct cleanup * make_cleanup_free_char_ptr_vec(VEC(char_ptr) *char_ptr_vec)
Definition: utils.c:3192
size
size_t size
Definition: go32-nat.c:242
do_cleanups
void do_cleanups(struct cleanup *old_chain)
Definition: cleanups.c:174
symfile.h