GDB (xrefs)
Loading...
Searching...
No Matches
solib-target.c
Go to the documentation of this file.
1/* Definitions for targets which report shared library events.
2
3 Copyright (C) 2007-2023 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 "objfiles.h"
22#include "solist.h"
23#include "symtab.h"
24#include "symfile.h"
25#include "target.h"
26#include "solib-target.h"
27#include <vector>
28#include "inferior.h"
29
30/* Private data for each loaded library. */
32{
33 /* The library's name. The name is normally kept in the struct
34 so_list; it is only here during XML parsing. */
35 std::string name;
36
37 /* The target can either specify segment bases or section bases, not
38 both. */
39
40 /* The base addresses for each independently relocatable segment of
41 this shared library. */
42 std::vector<CORE_ADDR> segment_bases;
43
44 /* The base addresses for each independently allocatable,
45 relocatable section of this shared library. */
46 std::vector<CORE_ADDR> section_bases;
47
48 /* The cached offsets for each section of this shared library,
49 determined from SEGMENT_BASES, or SECTION_BASES. */
51};
52
53typedef std::vector<std::unique_ptr<lm_info_target>> lm_info_vector;
54
55#if !defined(HAVE_LIBEXPAT)
56
57static lm_info_vector
58solib_target_parse_libraries (const char *library)
59{
60 static int have_warned;
61
62 if (!have_warned)
63 {
64 have_warned = 1;
65 warning (_("Can not parse XML library list; XML support was disabled "
66 "at compile time"));
67 }
68
69 return lm_info_vector ();
70}
71
72#else /* HAVE_LIBEXPAT */
73
74#include "xml-support.h"
75
76/* Handle the start of a <segment> element. */
77
78static void
79library_list_start_segment (struct gdb_xml_parser *parser,
80 const struct gdb_xml_element *element,
81 void *user_data,
82 std::vector<gdb_xml_value> &attributes)
83{
84 lm_info_vector *list = (lm_info_vector *) user_data;
85 lm_info_target *last = list->back ().get ();
86 ULONGEST *address_p
87 = (ULONGEST *) xml_find_attribute (attributes, "address")->value.get ();
88 CORE_ADDR address = (CORE_ADDR) *address_p;
89
90 if (!last->section_bases.empty ())
91 gdb_xml_error (parser,
92 _("Library list with both segments and sections"));
93
94 last->segment_bases.push_back (address);
95}
96
97static void
98library_list_start_section (struct gdb_xml_parser *parser,
99 const struct gdb_xml_element *element,
100 void *user_data,
101 std::vector<gdb_xml_value> &attributes)
102{
103 lm_info_vector *list = (lm_info_vector *) user_data;
104 lm_info_target *last = list->back ().get ();
105 ULONGEST *address_p
106 = (ULONGEST *) xml_find_attribute (attributes, "address")->value.get ();
107 CORE_ADDR address = (CORE_ADDR) *address_p;
108
109 if (!last->segment_bases.empty ())
110 gdb_xml_error (parser,
111 _("Library list with both segments and sections"));
112
113 last->section_bases.push_back (address);
114}
115
116/* Handle the start of a <library> element. */
117
118static void
119library_list_start_library (struct gdb_xml_parser *parser,
120 const struct gdb_xml_element *element,
121 void *user_data,
122 std::vector<gdb_xml_value> &attributes)
123{
124 lm_info_vector *list = (lm_info_vector *) user_data;
125 lm_info_target *item = new lm_info_target;
126 item->name
127 = (const char *) xml_find_attribute (attributes, "name")->value.get ();
128
129 list->emplace_back (item);
130}
131
132static void
133library_list_end_library (struct gdb_xml_parser *parser,
134 const struct gdb_xml_element *element,
135 void *user_data, const char *body_text)
136{
137 lm_info_vector *list = (lm_info_vector *) user_data;
138 lm_info_target *lm_info = list->back ().get ();
139
140 if (lm_info->segment_bases.empty () && lm_info->section_bases.empty ())
141 gdb_xml_error (parser, _("No segment or section bases defined"));
142}
143
144
145/* Handle the start of a <library-list> element. */
146
147static void
148library_list_start_list (struct gdb_xml_parser *parser,
149 const struct gdb_xml_element *element,
150 void *user_data,
151 std::vector<gdb_xml_value> &attributes)
152{
153 struct gdb_xml_value *version = xml_find_attribute (attributes, "version");
154
155 /* #FIXED attribute may be omitted, Expat returns NULL in such case. */
156 if (version != NULL)
157 {
158 const char *string = (const char *) version->value.get ();
159
160 if (strcmp (string, "1.0") != 0)
161 gdb_xml_error (parser,
162 _("Library list has unsupported version \"%s\""),
163 string);
164 }
165}
166
167/* The allowed elements and attributes for an XML library list.
168 The root element is a <library-list>. */
169
170static const struct gdb_xml_attribute segment_attributes[] = {
171 { "address", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
172 { NULL, GDB_XML_AF_NONE, NULL, NULL }
173};
174
175static const struct gdb_xml_attribute section_attributes[] = {
176 { "address", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL },
177 { NULL, GDB_XML_AF_NONE, NULL, NULL }
178};
179
180static const struct gdb_xml_element library_children[] = {
181 { "segment", segment_attributes, NULL,
183 library_list_start_segment, NULL },
184 { "section", section_attributes, NULL,
186 library_list_start_section, NULL },
187 { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
188};
189
190static const struct gdb_xml_attribute library_attributes[] = {
191 { "name", GDB_XML_AF_NONE, NULL, NULL },
192 { NULL, GDB_XML_AF_NONE, NULL, NULL }
193};
194
195static const struct gdb_xml_element library_list_children[] = {
196 { "library", library_attributes, library_children,
198 library_list_start_library, library_list_end_library },
199 { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
200};
201
202static const struct gdb_xml_attribute library_list_attributes[] = {
203 { "version", GDB_XML_AF_OPTIONAL, NULL, NULL },
204 { NULL, GDB_XML_AF_NONE, NULL, NULL }
205};
206
207static const struct gdb_xml_element library_list_elements[] = {
208 { "library-list", library_list_attributes, library_list_children,
209 GDB_XML_EF_NONE, library_list_start_list, NULL },
210 { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL }
211};
212
213static lm_info_vector
214solib_target_parse_libraries (const char *library)
215{
216 lm_info_vector result;
217
218 if (gdb_xml_parse_quick (_("target library list"), "library-list.dtd",
219 library_list_elements, library, &result) == 0)
220 {
221 /* Parsed successfully. */
222 return result;
223 }
224
225 result.clear ();
226 return result;
227}
228#endif
229
230static struct so_list *
232{
233 struct so_list *new_solib, *start = NULL, *last = NULL;
234
235 /* Fetch the list of shared libraries. */
236 gdb::optional<gdb::char_vector> library_document
237 = target_read_stralloc (current_inferior ()->top_target (),
239 if (!library_document)
240 return NULL;
241
242 /* Parse the list. */
243 lm_info_vector library_list
244 = solib_target_parse_libraries (library_document->data ());
245
246 if (library_list.empty ())
247 return NULL;
248
249 /* Build a struct so_list for each entry on the list. */
250 for (auto &&info : library_list)
251 {
252 new_solib = XCNEW (struct so_list);
253 strncpy (new_solib->so_name, info->name.c_str (),
255 new_solib->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0';
256 strncpy (new_solib->so_original_name, info->name.c_str (),
258 new_solib->so_original_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0';
259
260 /* We no longer need this copy of the name. */
261 info->name.clear ();
262
263 new_solib->lm_info = info.release ();
264
265 /* Add it to the list. */
266 if (!start)
267 last = start = new_solib;
268 else
269 {
270 last->next = new_solib;
271 last = new_solib;
272 }
273 }
274
275 return start;
276}
277
278static void
280{
281 /* Nothing needed. */
282}
283
284static void
286{
287 /* Nothing needed. */
288}
289
290static void
292{
294
295 gdb_assert (li->name.empty ());
296
297 delete li;
298}
299
300static void
302 struct target_section *sec)
303{
304 CORE_ADDR offset;
306
307 /* Build the offset table only once per object file. We can not do
308 it any earlier, since we need to open the file first. */
309 if (li->offsets.empty ())
310 {
311 int num_sections = gdb_bfd_count_sections (so->abfd);
312
313 li->offsets.assign (num_sections, 0);
314
315 if (!li->section_bases.empty ())
316 {
317 int i;
318 asection *sect;
319 int num_alloc_sections = 0;
320
321 for (i = 0, sect = so->abfd->sections;
322 sect != NULL;
323 i++, sect = sect->next)
324 if ((bfd_section_flags (sect) & SEC_ALLOC))
325 num_alloc_sections++;
326
327 if (num_alloc_sections != li->section_bases.size ())
328 warning (_("\
329Could not relocate shared library \"%s\": wrong number of ALLOC sections"),
330 so->so_name);
331 else
332 {
333 int bases_index = 0;
334 int found_range = 0;
335
336 so->addr_low = ~(CORE_ADDR) 0;
337 so->addr_high = 0;
338 for (i = 0, sect = so->abfd->sections;
339 sect != NULL;
340 i++, sect = sect->next)
341 {
342 if (!(bfd_section_flags (sect) & SEC_ALLOC))
343 continue;
344 if (bfd_section_size (sect) > 0)
345 {
346 CORE_ADDR low, high;
347
348 low = li->section_bases[i];
349 high = low + bfd_section_size (sect) - 1;
350
351 if (low < so->addr_low)
352 so->addr_low = low;
353 if (high > so->addr_high)
354 so->addr_high = high;
355 gdb_assert (so->addr_low <= so->addr_high);
356 found_range = 1;
357 }
358 li->offsets[i] = li->section_bases[bases_index];
359 bases_index++;
360 }
361 if (!found_range)
362 so->addr_low = so->addr_high = 0;
363 gdb_assert (so->addr_low <= so->addr_high);
364 }
365 }
366 else if (!li->segment_bases.empty ())
367 {
370
371 if (data == NULL)
372 warning (_("\
373Could not relocate shared library \"%s\": no segments"), so->so_name);
374 else
375 {
376 ULONGEST orig_delta;
377 int i;
378
379 if (!symfile_map_offsets_to_segments (so->abfd, data.get (),
380 li->offsets,
381 li->segment_bases.size (),
382 li->segment_bases.data ()))
383 warning (_("\
384Could not relocate shared library \"%s\": bad offsets"), so->so_name);
385
386 /* Find the range of addresses to report for this library in
387 "info sharedlibrary". Report any consecutive segments
388 which were relocated as a single unit. */
389 gdb_assert (li->segment_bases.size () > 0);
390 orig_delta = li->segment_bases[0] - data->segments[0].base;
391
392 for (i = 1; i < data->segments.size (); i++)
393 {
394 /* If we have run out of offsets, assume all
395 remaining segments have the same offset. */
396 if (i >= li->segment_bases.size ())
397 continue;
398
399 /* If this segment does not have the same offset, do
400 not include it in the library's range. */
401 if (li->segment_bases[i] - data->segments[i].base
402 != orig_delta)
403 break;
404 }
405
406 so->addr_low = li->segment_bases[0];
407 so->addr_high = (data->segments[i - 1].base
408 + data->segments[i - 1].size
409 + orig_delta);
410 gdb_assert (so->addr_low <= so->addr_high);
411 }
412 }
413 }
414
415 offset = li->offsets[gdb_bfd_section_index (sec->the_bfd_section->owner,
416 sec->the_bfd_section)];
417 sec->addr += offset;
418 sec->endaddr += offset;
419}
420
421static int
423{
424 /* We can't locate the main symbol file based on the target's
425 knowledge; the user has to specify it. */
426 return 0;
427}
428
429static int
431{
432 /* We don't have a range of addresses for the dynamic linker; there
433 may not be one in the program's address space. So only report
434 PLT entries (which may be import stubs). */
435 return in_plt_section (pc);
436}
437
static struct @5 attributes[]
int gdb_bfd_section_index(bfd *abfd, asection *section)
Definition gdb_bfd.c:984
int gdb_bfd_count_sections(bfd *abfd)
Definition gdb_bfd.c:1002
struct inferior * current_inferior(void)
Definition inferior.c:55
static int in_plt_section(CORE_ADDR pc)
Definition objfiles.h:972
static void solib_target_relocate_section_addresses(struct so_list *so, struct target_section *sec)
static int solib_target_open_symbol_file_object(int from_tty)
static lm_info_vector solib_target_parse_libraries(const char *library)
static int solib_target_in_dynsym_resolve_code(CORE_ADDR pc)
static void solib_target_clear_solib(void)
static struct so_list * solib_target_current_sos(void)
static void solib_target_free_so(struct so_list *so)
std::vector< std::unique_ptr< lm_info_target > > lm_info_vector
const struct target_so_ops solib_target_so_ops
static void solib_target_solib_create_inferior_hook(int from_tty)
gdb_bfd_ref_ptr solib_bfd_open(const char *pathname)
Definition solib.c:440
#define SO_NAME_MAX_PATH_SIZE
Definition solist.h:22
gdb::unique_xmalloc_ptr< void > value
Definition xml-support.h:78
std::vector< CORE_ADDR > segment_bases
std::vector< CORE_ADDR > section_bases
std::string name
section_offsets offsets
bfd * abfd
Definition solist.h:64
char so_name[SO_NAME_MAX_PATH_SIZE]
Definition solist.h:56
CORE_ADDR addr_high
Definition solist.h:80
struct so_list * next
Definition solist.h:40
char so_original_name[SO_NAME_MAX_PATH_SIZE]
Definition solist.h:53
lm_info_base * lm_info
Definition solist.h:46
CORE_ADDR addr_low
Definition solist.h:80
CORE_ADDR endaddr
struct bfd_section * the_bfd_section
symfile_segment_data_up get_symfile_segment_data(bfd *abfd)
Definition symfile.c:3642
int symfile_map_offsets_to_segments(bfd *abfd, const struct symfile_segment_data *data, section_offsets &offsets, int num_segment_bases, const CORE_ADDR *segment_bases)
Definition symfile.c:3668
std::unique_ptr< symfile_segment_data > symfile_segment_data_up
Definition symfile.h:104
std::vector< CORE_ADDR > section_offsets
Definition symtab.h:1669
gdb::optional< gdb::char_vector > target_read_stralloc(struct target_ops *ops, enum target_object object, const char *annex)
Definition target.c:2321
@ TARGET_OBJECT_LIBRARIES
Definition target.h:176
const char version[]
Definition version.c:2
@ GDB_XML_EF_NONE
@ GDB_XML_EF_REPEATABLE
@ GDB_XML_EF_OPTIONAL
void void gdb_xml_error(struct gdb_xml_parser *parser, const char *format,...) ATTRIBUTE_NORETURN ATTRIBUTE_PRINTF(2
void void struct gdb_xml_value * xml_find_attribute(std::vector< gdb_xml_value > &attributes, const char *name)
int gdb_xml_parse_quick(const char *name, const char *dtd_name, const struct gdb_xml_element *elements, const char *document, void *user_data)
gdb_xml_attribute_handler gdb_xml_parse_attr_ulongest
@ GDB_XML_AF_OPTIONAL
@ GDB_XML_AF_NONE