Commit | Line | Data |
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ab31aa69 | 1 | /* Handle SVR4 shared libraries for GDB, the GNU Debugger. |
2f4950cd | 2 | |
ecd75fc8 | 3 | Copyright (C) 1990-2014 Free Software Foundation, Inc. |
13437d4b KB |
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 | |
a9762ec7 | 9 | the Free Software Foundation; either version 3 of the License, or |
13437d4b KB |
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 | |
a9762ec7 | 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
13437d4b | 19 | |
13437d4b KB |
20 | #include "defs.h" |
21 | ||
13437d4b | 22 | #include "elf/external.h" |
21479ded | 23 | #include "elf/common.h" |
f7856c8f | 24 | #include "elf/mips.h" |
13437d4b KB |
25 | |
26 | #include "symtab.h" | |
27 | #include "bfd.h" | |
28 | #include "symfile.h" | |
29 | #include "objfiles.h" | |
30 | #include "gdbcore.h" | |
13437d4b | 31 | #include "target.h" |
13437d4b | 32 | #include "inferior.h" |
45741a9c | 33 | #include "infrun.h" |
fb14de7b | 34 | #include "regcache.h" |
2020b7ab | 35 | #include "gdbthread.h" |
1a816a87 | 36 | #include "observer.h" |
13437d4b KB |
37 | |
38 | #include "solist.h" | |
bba93f6c | 39 | #include "solib.h" |
13437d4b KB |
40 | #include "solib-svr4.h" |
41 | ||
2f4950cd | 42 | #include "bfd-target.h" |
cc10cae3 | 43 | #include "elf-bfd.h" |
2f4950cd | 44 | #include "exec.h" |
8d4e36ba | 45 | #include "auxv.h" |
695c3173 | 46 | #include "gdb_bfd.h" |
f9e14852 | 47 | #include "probe.h" |
2f4950cd | 48 | |
e5e2b9ff | 49 | static struct link_map_offsets *svr4_fetch_link_map_offsets (void); |
d5a921c9 | 50 | static int svr4_have_link_map_offsets (void); |
9f2982ff | 51 | static void svr4_relocate_main_executable (void); |
f9e14852 | 52 | static void svr4_free_library_list (void *p_list); |
1c4dcb57 | 53 | |
c378eb4e | 54 | /* Link map info to include in an allocated so_list entry. */ |
13437d4b KB |
55 | |
56 | struct lm_info | |
57 | { | |
cc10cae3 | 58 | /* Amount by which addresses in the binary should be relocated to |
3957565a JK |
59 | match the inferior. The direct inferior value is L_ADDR_INFERIOR. |
60 | When prelinking is involved and the prelink base address changes, | |
61 | we may need a different offset - the recomputed offset is in L_ADDR. | |
62 | It is commonly the same value. It is cached as we want to warn about | |
63 | the difference and compute it only once. L_ADDR is valid | |
64 | iff L_ADDR_P. */ | |
65 | CORE_ADDR l_addr, l_addr_inferior; | |
66 | unsigned int l_addr_p : 1; | |
93a57060 DJ |
67 | |
68 | /* The target location of lm. */ | |
69 | CORE_ADDR lm_addr; | |
3957565a JK |
70 | |
71 | /* Values read in from inferior's fields of the same name. */ | |
72 | CORE_ADDR l_ld, l_next, l_prev, l_name; | |
13437d4b KB |
73 | }; |
74 | ||
75 | /* On SVR4 systems, a list of symbols in the dynamic linker where | |
76 | GDB can try to place a breakpoint to monitor shared library | |
77 | events. | |
78 | ||
79 | If none of these symbols are found, or other errors occur, then | |
80 | SVR4 systems will fall back to using a symbol as the "startup | |
81 | mapping complete" breakpoint address. */ | |
82 | ||
bc043ef3 | 83 | static const char * const solib_break_names[] = |
13437d4b KB |
84 | { |
85 | "r_debug_state", | |
86 | "_r_debug_state", | |
87 | "_dl_debug_state", | |
88 | "rtld_db_dlactivity", | |
4c7dcb84 | 89 | "__dl_rtld_db_dlactivity", |
1f72e589 | 90 | "_rtld_debug_state", |
4c0122c8 | 91 | |
13437d4b KB |
92 | NULL |
93 | }; | |
13437d4b | 94 | |
bc043ef3 | 95 | static const char * const bkpt_names[] = |
13437d4b | 96 | { |
13437d4b | 97 | "_start", |
ad3dcc5c | 98 | "__start", |
13437d4b KB |
99 | "main", |
100 | NULL | |
101 | }; | |
13437d4b | 102 | |
bc043ef3 | 103 | static const char * const main_name_list[] = |
13437d4b KB |
104 | { |
105 | "main_$main", | |
106 | NULL | |
107 | }; | |
108 | ||
f9e14852 GB |
109 | /* What to do when a probe stop occurs. */ |
110 | ||
111 | enum probe_action | |
112 | { | |
113 | /* Something went seriously wrong. Stop using probes and | |
114 | revert to using the older interface. */ | |
115 | PROBES_INTERFACE_FAILED, | |
116 | ||
117 | /* No action is required. The shared object list is still | |
118 | valid. */ | |
119 | DO_NOTHING, | |
120 | ||
121 | /* The shared object list should be reloaded entirely. */ | |
122 | FULL_RELOAD, | |
123 | ||
124 | /* Attempt to incrementally update the shared object list. If | |
125 | the update fails or is not possible, fall back to reloading | |
126 | the list in full. */ | |
127 | UPDATE_OR_RELOAD, | |
128 | }; | |
129 | ||
130 | /* A probe's name and its associated action. */ | |
131 | ||
132 | struct probe_info | |
133 | { | |
134 | /* The name of the probe. */ | |
135 | const char *name; | |
136 | ||
137 | /* What to do when a probe stop occurs. */ | |
138 | enum probe_action action; | |
139 | }; | |
140 | ||
141 | /* A list of named probes and their associated actions. If all | |
142 | probes are present in the dynamic linker then the probes-based | |
143 | interface will be used. */ | |
144 | ||
145 | static const struct probe_info probe_info[] = | |
146 | { | |
147 | { "init_start", DO_NOTHING }, | |
148 | { "init_complete", FULL_RELOAD }, | |
149 | { "map_start", DO_NOTHING }, | |
150 | { "map_failed", DO_NOTHING }, | |
151 | { "reloc_complete", UPDATE_OR_RELOAD }, | |
152 | { "unmap_start", DO_NOTHING }, | |
153 | { "unmap_complete", FULL_RELOAD }, | |
154 | }; | |
155 | ||
156 | #define NUM_PROBES ARRAY_SIZE (probe_info) | |
157 | ||
4d7b2d5b JB |
158 | /* Return non-zero if GDB_SO_NAME and INFERIOR_SO_NAME represent |
159 | the same shared library. */ | |
160 | ||
161 | static int | |
162 | svr4_same_1 (const char *gdb_so_name, const char *inferior_so_name) | |
163 | { | |
164 | if (strcmp (gdb_so_name, inferior_so_name) == 0) | |
165 | return 1; | |
166 | ||
167 | /* On Solaris, when starting inferior we think that dynamic linker is | |
d989b283 PP |
168 | /usr/lib/ld.so.1, but later on, the table of loaded shared libraries |
169 | contains /lib/ld.so.1. Sometimes one file is a link to another, but | |
4d7b2d5b JB |
170 | sometimes they have identical content, but are not linked to each |
171 | other. We don't restrict this check for Solaris, but the chances | |
172 | of running into this situation elsewhere are very low. */ | |
173 | if (strcmp (gdb_so_name, "/usr/lib/ld.so.1") == 0 | |
174 | && strcmp (inferior_so_name, "/lib/ld.so.1") == 0) | |
175 | return 1; | |
176 | ||
177 | /* Similarly, we observed the same issue with sparc64, but with | |
178 | different locations. */ | |
179 | if (strcmp (gdb_so_name, "/usr/lib/sparcv9/ld.so.1") == 0 | |
180 | && strcmp (inferior_so_name, "/lib/sparcv9/ld.so.1") == 0) | |
181 | return 1; | |
182 | ||
183 | return 0; | |
184 | } | |
185 | ||
186 | static int | |
187 | svr4_same (struct so_list *gdb, struct so_list *inferior) | |
188 | { | |
189 | return (svr4_same_1 (gdb->so_original_name, inferior->so_original_name)); | |
190 | } | |
191 | ||
3957565a JK |
192 | static struct lm_info * |
193 | lm_info_read (CORE_ADDR lm_addr) | |
13437d4b | 194 | { |
4b188b9f | 195 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); |
3957565a JK |
196 | gdb_byte *lm; |
197 | struct lm_info *lm_info; | |
198 | struct cleanup *back_to; | |
199 | ||
200 | lm = xmalloc (lmo->link_map_size); | |
201 | back_to = make_cleanup (xfree, lm); | |
202 | ||
203 | if (target_read_memory (lm_addr, lm, lmo->link_map_size) != 0) | |
204 | { | |
205 | warning (_("Error reading shared library list entry at %s"), | |
f5656ead | 206 | paddress (target_gdbarch (), lm_addr)), |
3957565a JK |
207 | lm_info = NULL; |
208 | } | |
209 | else | |
210 | { | |
f5656ead | 211 | struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr; |
13437d4b | 212 | |
3957565a JK |
213 | lm_info = xzalloc (sizeof (*lm_info)); |
214 | lm_info->lm_addr = lm_addr; | |
215 | ||
216 | lm_info->l_addr_inferior = extract_typed_address (&lm[lmo->l_addr_offset], | |
217 | ptr_type); | |
218 | lm_info->l_ld = extract_typed_address (&lm[lmo->l_ld_offset], ptr_type); | |
219 | lm_info->l_next = extract_typed_address (&lm[lmo->l_next_offset], | |
220 | ptr_type); | |
221 | lm_info->l_prev = extract_typed_address (&lm[lmo->l_prev_offset], | |
222 | ptr_type); | |
223 | lm_info->l_name = extract_typed_address (&lm[lmo->l_name_offset], | |
224 | ptr_type); | |
225 | } | |
226 | ||
227 | do_cleanups (back_to); | |
228 | ||
229 | return lm_info; | |
13437d4b KB |
230 | } |
231 | ||
cc10cae3 | 232 | static int |
b23518f0 | 233 | has_lm_dynamic_from_link_map (void) |
cc10cae3 AO |
234 | { |
235 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); | |
236 | ||
cfaefc65 | 237 | return lmo->l_ld_offset >= 0; |
cc10cae3 AO |
238 | } |
239 | ||
cc10cae3 | 240 | static CORE_ADDR |
f65ce5fb | 241 | lm_addr_check (const struct so_list *so, bfd *abfd) |
cc10cae3 | 242 | { |
3957565a | 243 | if (!so->lm_info->l_addr_p) |
cc10cae3 AO |
244 | { |
245 | struct bfd_section *dyninfo_sect; | |
28f34a8f | 246 | CORE_ADDR l_addr, l_dynaddr, dynaddr; |
cc10cae3 | 247 | |
3957565a | 248 | l_addr = so->lm_info->l_addr_inferior; |
cc10cae3 | 249 | |
b23518f0 | 250 | if (! abfd || ! has_lm_dynamic_from_link_map ()) |
cc10cae3 AO |
251 | goto set_addr; |
252 | ||
3957565a | 253 | l_dynaddr = so->lm_info->l_ld; |
cc10cae3 AO |
254 | |
255 | dyninfo_sect = bfd_get_section_by_name (abfd, ".dynamic"); | |
256 | if (dyninfo_sect == NULL) | |
257 | goto set_addr; | |
258 | ||
259 | dynaddr = bfd_section_vma (abfd, dyninfo_sect); | |
260 | ||
261 | if (dynaddr + l_addr != l_dynaddr) | |
262 | { | |
28f34a8f | 263 | CORE_ADDR align = 0x1000; |
4e1fc9c9 | 264 | CORE_ADDR minpagesize = align; |
28f34a8f | 265 | |
cc10cae3 AO |
266 | if (bfd_get_flavour (abfd) == bfd_target_elf_flavour) |
267 | { | |
268 | Elf_Internal_Ehdr *ehdr = elf_tdata (abfd)->elf_header; | |
269 | Elf_Internal_Phdr *phdr = elf_tdata (abfd)->phdr; | |
270 | int i; | |
271 | ||
272 | align = 1; | |
273 | ||
274 | for (i = 0; i < ehdr->e_phnum; i++) | |
275 | if (phdr[i].p_type == PT_LOAD && phdr[i].p_align > align) | |
276 | align = phdr[i].p_align; | |
4e1fc9c9 JK |
277 | |
278 | minpagesize = get_elf_backend_data (abfd)->minpagesize; | |
cc10cae3 AO |
279 | } |
280 | ||
281 | /* Turn it into a mask. */ | |
282 | align--; | |
283 | ||
284 | /* If the changes match the alignment requirements, we | |
285 | assume we're using a core file that was generated by the | |
286 | same binary, just prelinked with a different base offset. | |
287 | If it doesn't match, we may have a different binary, the | |
288 | same binary with the dynamic table loaded at an unrelated | |
289 | location, or anything, really. To avoid regressions, | |
290 | don't adjust the base offset in the latter case, although | |
291 | odds are that, if things really changed, debugging won't | |
5c0d192f JK |
292 | quite work. |
293 | ||
294 | One could expect more the condition | |
295 | ((l_addr & align) == 0 && ((l_dynaddr - dynaddr) & align) == 0) | |
296 | but the one below is relaxed for PPC. The PPC kernel supports | |
297 | either 4k or 64k page sizes. To be prepared for 64k pages, | |
298 | PPC ELF files are built using an alignment requirement of 64k. | |
299 | However, when running on a kernel supporting 4k pages, the memory | |
300 | mapping of the library may not actually happen on a 64k boundary! | |
301 | ||
302 | (In the usual case where (l_addr & align) == 0, this check is | |
4e1fc9c9 JK |
303 | equivalent to the possibly expected check above.) |
304 | ||
305 | Even on PPC it must be zero-aligned at least for MINPAGESIZE. */ | |
5c0d192f | 306 | |
02835898 JK |
307 | l_addr = l_dynaddr - dynaddr; |
308 | ||
4e1fc9c9 JK |
309 | if ((l_addr & (minpagesize - 1)) == 0 |
310 | && (l_addr & align) == ((l_dynaddr - dynaddr) & align)) | |
cc10cae3 | 311 | { |
701ed6dc | 312 | if (info_verbose) |
ccf26247 JK |
313 | printf_unfiltered (_("Using PIC (Position Independent Code) " |
314 | "prelink displacement %s for \"%s\".\n"), | |
f5656ead | 315 | paddress (target_gdbarch (), l_addr), |
ccf26247 | 316 | so->so_name); |
cc10cae3 | 317 | } |
79d4c408 | 318 | else |
02835898 JK |
319 | { |
320 | /* There is no way to verify the library file matches. prelink | |
321 | can during prelinking of an unprelinked file (or unprelinking | |
322 | of a prelinked file) shift the DYNAMIC segment by arbitrary | |
323 | offset without any page size alignment. There is no way to | |
324 | find out the ELF header and/or Program Headers for a limited | |
325 | verification if it they match. One could do a verification | |
326 | of the DYNAMIC segment. Still the found address is the best | |
327 | one GDB could find. */ | |
328 | ||
329 | warning (_(".dynamic section for \"%s\" " | |
330 | "is not at the expected address " | |
331 | "(wrong library or version mismatch?)"), so->so_name); | |
332 | } | |
cc10cae3 AO |
333 | } |
334 | ||
335 | set_addr: | |
336 | so->lm_info->l_addr = l_addr; | |
3957565a | 337 | so->lm_info->l_addr_p = 1; |
cc10cae3 AO |
338 | } |
339 | ||
340 | return so->lm_info->l_addr; | |
341 | } | |
342 | ||
6c95b8df | 343 | /* Per pspace SVR4 specific data. */ |
13437d4b | 344 | |
1a816a87 PA |
345 | struct svr4_info |
346 | { | |
c378eb4e | 347 | CORE_ADDR debug_base; /* Base of dynamic linker structures. */ |
1a816a87 PA |
348 | |
349 | /* Validity flag for debug_loader_offset. */ | |
350 | int debug_loader_offset_p; | |
351 | ||
352 | /* Load address for the dynamic linker, inferred. */ | |
353 | CORE_ADDR debug_loader_offset; | |
354 | ||
355 | /* Name of the dynamic linker, valid if debug_loader_offset_p. */ | |
356 | char *debug_loader_name; | |
357 | ||
358 | /* Load map address for the main executable. */ | |
359 | CORE_ADDR main_lm_addr; | |
1a816a87 | 360 | |
6c95b8df PA |
361 | CORE_ADDR interp_text_sect_low; |
362 | CORE_ADDR interp_text_sect_high; | |
363 | CORE_ADDR interp_plt_sect_low; | |
364 | CORE_ADDR interp_plt_sect_high; | |
f9e14852 GB |
365 | |
366 | /* Nonzero if the list of objects was last obtained from the target | |
367 | via qXfer:libraries-svr4:read. */ | |
368 | int using_xfer; | |
369 | ||
370 | /* Table of struct probe_and_action instances, used by the | |
371 | probes-based interface to map breakpoint addresses to probes | |
372 | and their associated actions. Lookup is performed using | |
373 | probe_and_action->probe->address. */ | |
374 | htab_t probes_table; | |
375 | ||
376 | /* List of objects loaded into the inferior, used by the probes- | |
377 | based interface. */ | |
378 | struct so_list *solib_list; | |
6c95b8df | 379 | }; |
1a816a87 | 380 | |
6c95b8df PA |
381 | /* Per-program-space data key. */ |
382 | static const struct program_space_data *solib_svr4_pspace_data; | |
1a816a87 | 383 | |
f9e14852 GB |
384 | /* Free the probes table. */ |
385 | ||
386 | static void | |
387 | free_probes_table (struct svr4_info *info) | |
388 | { | |
389 | if (info->probes_table == NULL) | |
390 | return; | |
391 | ||
392 | htab_delete (info->probes_table); | |
393 | info->probes_table = NULL; | |
394 | } | |
395 | ||
396 | /* Free the solib list. */ | |
397 | ||
398 | static void | |
399 | free_solib_list (struct svr4_info *info) | |
400 | { | |
401 | svr4_free_library_list (&info->solib_list); | |
402 | info->solib_list = NULL; | |
403 | } | |
404 | ||
6c95b8df PA |
405 | static void |
406 | svr4_pspace_data_cleanup (struct program_space *pspace, void *arg) | |
1a816a87 | 407 | { |
487ad57c | 408 | struct svr4_info *info = arg; |
f9e14852 GB |
409 | |
410 | free_probes_table (info); | |
411 | free_solib_list (info); | |
412 | ||
6c95b8df | 413 | xfree (info); |
1a816a87 PA |
414 | } |
415 | ||
6c95b8df PA |
416 | /* Get the current svr4 data. If none is found yet, add it now. This |
417 | function always returns a valid object. */ | |
34439770 | 418 | |
6c95b8df PA |
419 | static struct svr4_info * |
420 | get_svr4_info (void) | |
1a816a87 | 421 | { |
6c95b8df | 422 | struct svr4_info *info; |
1a816a87 | 423 | |
6c95b8df PA |
424 | info = program_space_data (current_program_space, solib_svr4_pspace_data); |
425 | if (info != NULL) | |
426 | return info; | |
34439770 | 427 | |
41bf6aca | 428 | info = XCNEW (struct svr4_info); |
6c95b8df PA |
429 | set_program_space_data (current_program_space, solib_svr4_pspace_data, info); |
430 | return info; | |
1a816a87 | 431 | } |
93a57060 | 432 | |
13437d4b KB |
433 | /* Local function prototypes */ |
434 | ||
bc043ef3 | 435 | static int match_main (const char *); |
13437d4b | 436 | |
97ec2c2f UW |
437 | /* Read program header TYPE from inferior memory. The header is found |
438 | by scanning the OS auxillary vector. | |
439 | ||
09919ac2 JK |
440 | If TYPE == -1, return the program headers instead of the contents of |
441 | one program header. | |
442 | ||
97ec2c2f UW |
443 | Return a pointer to allocated memory holding the program header contents, |
444 | or NULL on failure. If sucessful, and unless P_SECT_SIZE is NULL, the | |
445 | size of those contents is returned to P_SECT_SIZE. Likewise, the target | |
446 | architecture size (32-bit or 64-bit) is returned to P_ARCH_SIZE. */ | |
447 | ||
448 | static gdb_byte * | |
449 | read_program_header (int type, int *p_sect_size, int *p_arch_size) | |
450 | { | |
f5656ead | 451 | enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); |
43136979 | 452 | CORE_ADDR at_phdr, at_phent, at_phnum, pt_phdr = 0; |
97ec2c2f UW |
453 | int arch_size, sect_size; |
454 | CORE_ADDR sect_addr; | |
455 | gdb_byte *buf; | |
43136979 | 456 | int pt_phdr_p = 0; |
97ec2c2f UW |
457 | |
458 | /* Get required auxv elements from target. */ | |
459 | if (target_auxv_search (¤t_target, AT_PHDR, &at_phdr) <= 0) | |
460 | return 0; | |
461 | if (target_auxv_search (¤t_target, AT_PHENT, &at_phent) <= 0) | |
462 | return 0; | |
463 | if (target_auxv_search (¤t_target, AT_PHNUM, &at_phnum) <= 0) | |
464 | return 0; | |
465 | if (!at_phdr || !at_phnum) | |
466 | return 0; | |
467 | ||
468 | /* Determine ELF architecture type. */ | |
469 | if (at_phent == sizeof (Elf32_External_Phdr)) | |
470 | arch_size = 32; | |
471 | else if (at_phent == sizeof (Elf64_External_Phdr)) | |
472 | arch_size = 64; | |
473 | else | |
474 | return 0; | |
475 | ||
09919ac2 JK |
476 | /* Find the requested segment. */ |
477 | if (type == -1) | |
478 | { | |
479 | sect_addr = at_phdr; | |
480 | sect_size = at_phent * at_phnum; | |
481 | } | |
482 | else if (arch_size == 32) | |
97ec2c2f UW |
483 | { |
484 | Elf32_External_Phdr phdr; | |
485 | int i; | |
486 | ||
487 | /* Search for requested PHDR. */ | |
488 | for (i = 0; i < at_phnum; i++) | |
489 | { | |
43136979 AR |
490 | int p_type; |
491 | ||
97ec2c2f UW |
492 | if (target_read_memory (at_phdr + i * sizeof (phdr), |
493 | (gdb_byte *)&phdr, sizeof (phdr))) | |
494 | return 0; | |
495 | ||
43136979 AR |
496 | p_type = extract_unsigned_integer ((gdb_byte *) phdr.p_type, |
497 | 4, byte_order); | |
498 | ||
499 | if (p_type == PT_PHDR) | |
500 | { | |
501 | pt_phdr_p = 1; | |
502 | pt_phdr = extract_unsigned_integer ((gdb_byte *) phdr.p_vaddr, | |
503 | 4, byte_order); | |
504 | } | |
505 | ||
506 | if (p_type == type) | |
97ec2c2f UW |
507 | break; |
508 | } | |
509 | ||
510 | if (i == at_phnum) | |
511 | return 0; | |
512 | ||
513 | /* Retrieve address and size. */ | |
e17a4113 UW |
514 | sect_addr = extract_unsigned_integer ((gdb_byte *)phdr.p_vaddr, |
515 | 4, byte_order); | |
516 | sect_size = extract_unsigned_integer ((gdb_byte *)phdr.p_memsz, | |
517 | 4, byte_order); | |
97ec2c2f UW |
518 | } |
519 | else | |
520 | { | |
521 | Elf64_External_Phdr phdr; | |
522 | int i; | |
523 | ||
524 | /* Search for requested PHDR. */ | |
525 | for (i = 0; i < at_phnum; i++) | |
526 | { | |
43136979 AR |
527 | int p_type; |
528 | ||
97ec2c2f UW |
529 | if (target_read_memory (at_phdr + i * sizeof (phdr), |
530 | (gdb_byte *)&phdr, sizeof (phdr))) | |
531 | return 0; | |
532 | ||
43136979 AR |
533 | p_type = extract_unsigned_integer ((gdb_byte *) phdr.p_type, |
534 | 4, byte_order); | |
535 | ||
536 | if (p_type == PT_PHDR) | |
537 | { | |
538 | pt_phdr_p = 1; | |
539 | pt_phdr = extract_unsigned_integer ((gdb_byte *) phdr.p_vaddr, | |
540 | 8, byte_order); | |
541 | } | |
542 | ||
543 | if (p_type == type) | |
97ec2c2f UW |
544 | break; |
545 | } | |
546 | ||
547 | if (i == at_phnum) | |
548 | return 0; | |
549 | ||
550 | /* Retrieve address and size. */ | |
e17a4113 UW |
551 | sect_addr = extract_unsigned_integer ((gdb_byte *)phdr.p_vaddr, |
552 | 8, byte_order); | |
553 | sect_size = extract_unsigned_integer ((gdb_byte *)phdr.p_memsz, | |
554 | 8, byte_order); | |
97ec2c2f UW |
555 | } |
556 | ||
43136979 AR |
557 | /* PT_PHDR is optional, but we really need it |
558 | for PIE to make this work in general. */ | |
559 | ||
560 | if (pt_phdr_p) | |
561 | { | |
562 | /* at_phdr is real address in memory. pt_phdr is what pheader says it is. | |
563 | Relocation offset is the difference between the two. */ | |
564 | sect_addr = sect_addr + (at_phdr - pt_phdr); | |
565 | } | |
566 | ||
97ec2c2f UW |
567 | /* Read in requested program header. */ |
568 | buf = xmalloc (sect_size); | |
569 | if (target_read_memory (sect_addr, buf, sect_size)) | |
570 | { | |
571 | xfree (buf); | |
572 | return NULL; | |
573 | } | |
574 | ||
575 | if (p_arch_size) | |
576 | *p_arch_size = arch_size; | |
577 | if (p_sect_size) | |
578 | *p_sect_size = sect_size; | |
579 | ||
580 | return buf; | |
581 | } | |
582 | ||
583 | ||
584 | /* Return program interpreter string. */ | |
001f13d8 | 585 | static char * |
97ec2c2f UW |
586 | find_program_interpreter (void) |
587 | { | |
588 | gdb_byte *buf = NULL; | |
589 | ||
590 | /* If we have an exec_bfd, use its section table. */ | |
591 | if (exec_bfd | |
592 | && bfd_get_flavour (exec_bfd) == bfd_target_elf_flavour) | |
593 | { | |
594 | struct bfd_section *interp_sect; | |
595 | ||
596 | interp_sect = bfd_get_section_by_name (exec_bfd, ".interp"); | |
597 | if (interp_sect != NULL) | |
598 | { | |
97ec2c2f UW |
599 | int sect_size = bfd_section_size (exec_bfd, interp_sect); |
600 | ||
601 | buf = xmalloc (sect_size); | |
602 | bfd_get_section_contents (exec_bfd, interp_sect, buf, 0, sect_size); | |
603 | } | |
604 | } | |
605 | ||
606 | /* If we didn't find it, use the target auxillary vector. */ | |
607 | if (!buf) | |
608 | buf = read_program_header (PT_INTERP, NULL, NULL); | |
609 | ||
001f13d8 | 610 | return (char *) buf; |
97ec2c2f UW |
611 | } |
612 | ||
613 | ||
b6d7a4bf SM |
614 | /* Scan for DESIRED_DYNTAG in .dynamic section of ABFD. If DESIRED_DYNTAG is |
615 | found, 1 is returned and the corresponding PTR is set. */ | |
3a40aaa0 UW |
616 | |
617 | static int | |
b6d7a4bf | 618 | scan_dyntag (const int desired_dyntag, bfd *abfd, CORE_ADDR *ptr) |
3a40aaa0 UW |
619 | { |
620 | int arch_size, step, sect_size; | |
b6d7a4bf | 621 | long current_dyntag; |
b381ea14 | 622 | CORE_ADDR dyn_ptr, dyn_addr; |
65728c26 | 623 | gdb_byte *bufend, *bufstart, *buf; |
3a40aaa0 UW |
624 | Elf32_External_Dyn *x_dynp_32; |
625 | Elf64_External_Dyn *x_dynp_64; | |
626 | struct bfd_section *sect; | |
61f0d762 | 627 | struct target_section *target_section; |
3a40aaa0 UW |
628 | |
629 | if (abfd == NULL) | |
630 | return 0; | |
0763ab81 PA |
631 | |
632 | if (bfd_get_flavour (abfd) != bfd_target_elf_flavour) | |
633 | return 0; | |
634 | ||
3a40aaa0 UW |
635 | arch_size = bfd_get_arch_size (abfd); |
636 | if (arch_size == -1) | |
0763ab81 | 637 | return 0; |
3a40aaa0 UW |
638 | |
639 | /* Find the start address of the .dynamic section. */ | |
640 | sect = bfd_get_section_by_name (abfd, ".dynamic"); | |
641 | if (sect == NULL) | |
642 | return 0; | |
61f0d762 JK |
643 | |
644 | for (target_section = current_target_sections->sections; | |
645 | target_section < current_target_sections->sections_end; | |
646 | target_section++) | |
647 | if (sect == target_section->the_bfd_section) | |
648 | break; | |
b381ea14 JK |
649 | if (target_section < current_target_sections->sections_end) |
650 | dyn_addr = target_section->addr; | |
651 | else | |
652 | { | |
653 | /* ABFD may come from OBJFILE acting only as a symbol file without being | |
654 | loaded into the target (see add_symbol_file_command). This case is | |
655 | such fallback to the file VMA address without the possibility of | |
656 | having the section relocated to its actual in-memory address. */ | |
657 | ||
658 | dyn_addr = bfd_section_vma (abfd, sect); | |
659 | } | |
3a40aaa0 | 660 | |
65728c26 DJ |
661 | /* Read in .dynamic from the BFD. We will get the actual value |
662 | from memory later. */ | |
3a40aaa0 | 663 | sect_size = bfd_section_size (abfd, sect); |
65728c26 DJ |
664 | buf = bufstart = alloca (sect_size); |
665 | if (!bfd_get_section_contents (abfd, sect, | |
666 | buf, 0, sect_size)) | |
667 | return 0; | |
3a40aaa0 UW |
668 | |
669 | /* Iterate over BUF and scan for DYNTAG. If found, set PTR and return. */ | |
670 | step = (arch_size == 32) ? sizeof (Elf32_External_Dyn) | |
671 | : sizeof (Elf64_External_Dyn); | |
672 | for (bufend = buf + sect_size; | |
673 | buf < bufend; | |
674 | buf += step) | |
675 | { | |
676 | if (arch_size == 32) | |
677 | { | |
678 | x_dynp_32 = (Elf32_External_Dyn *) buf; | |
b6d7a4bf | 679 | current_dyntag = bfd_h_get_32 (abfd, (bfd_byte *) x_dynp_32->d_tag); |
3a40aaa0 UW |
680 | dyn_ptr = bfd_h_get_32 (abfd, (bfd_byte *) x_dynp_32->d_un.d_ptr); |
681 | } | |
65728c26 | 682 | else |
3a40aaa0 UW |
683 | { |
684 | x_dynp_64 = (Elf64_External_Dyn *) buf; | |
b6d7a4bf | 685 | current_dyntag = bfd_h_get_64 (abfd, (bfd_byte *) x_dynp_64->d_tag); |
3a40aaa0 UW |
686 | dyn_ptr = bfd_h_get_64 (abfd, (bfd_byte *) x_dynp_64->d_un.d_ptr); |
687 | } | |
b6d7a4bf | 688 | if (current_dyntag == DT_NULL) |
3a40aaa0 | 689 | return 0; |
b6d7a4bf | 690 | if (current_dyntag == desired_dyntag) |
3a40aaa0 | 691 | { |
65728c26 DJ |
692 | /* If requested, try to read the runtime value of this .dynamic |
693 | entry. */ | |
3a40aaa0 | 694 | if (ptr) |
65728c26 | 695 | { |
b6da22b0 | 696 | struct type *ptr_type; |
65728c26 DJ |
697 | gdb_byte ptr_buf[8]; |
698 | CORE_ADDR ptr_addr; | |
699 | ||
f5656ead | 700 | ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr; |
b381ea14 | 701 | ptr_addr = dyn_addr + (buf - bufstart) + arch_size / 8; |
65728c26 | 702 | if (target_read_memory (ptr_addr, ptr_buf, arch_size / 8) == 0) |
b6da22b0 | 703 | dyn_ptr = extract_typed_address (ptr_buf, ptr_type); |
65728c26 DJ |
704 | *ptr = dyn_ptr; |
705 | } | |
706 | return 1; | |
3a40aaa0 UW |
707 | } |
708 | } | |
709 | ||
710 | return 0; | |
711 | } | |
712 | ||
b6d7a4bf SM |
713 | /* Scan for DESIRED_DYNTAG in .dynamic section of the target's main executable, |
714 | found by consulting the OS auxillary vector. If DESIRED_DYNTAG is found, 1 | |
715 | is returned and the corresponding PTR is set. */ | |
97ec2c2f UW |
716 | |
717 | static int | |
b6d7a4bf | 718 | scan_dyntag_auxv (const int desired_dyntag, CORE_ADDR *ptr) |
97ec2c2f | 719 | { |
f5656ead | 720 | enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); |
97ec2c2f | 721 | int sect_size, arch_size, step; |
b6d7a4bf | 722 | long current_dyntag; |
97ec2c2f UW |
723 | CORE_ADDR dyn_ptr; |
724 | gdb_byte *bufend, *bufstart, *buf; | |
725 | ||
726 | /* Read in .dynamic section. */ | |
727 | buf = bufstart = read_program_header (PT_DYNAMIC, §_size, &arch_size); | |
728 | if (!buf) | |
729 | return 0; | |
730 | ||
731 | /* Iterate over BUF and scan for DYNTAG. If found, set PTR and return. */ | |
732 | step = (arch_size == 32) ? sizeof (Elf32_External_Dyn) | |
733 | : sizeof (Elf64_External_Dyn); | |
734 | for (bufend = buf + sect_size; | |
735 | buf < bufend; | |
736 | buf += step) | |
737 | { | |
738 | if (arch_size == 32) | |
739 | { | |
740 | Elf32_External_Dyn *dynp = (Elf32_External_Dyn *) buf; | |
433759f7 | 741 | |
b6d7a4bf | 742 | current_dyntag = extract_unsigned_integer ((gdb_byte *) dynp->d_tag, |
e17a4113 UW |
743 | 4, byte_order); |
744 | dyn_ptr = extract_unsigned_integer ((gdb_byte *) dynp->d_un.d_ptr, | |
745 | 4, byte_order); | |
97ec2c2f UW |
746 | } |
747 | else | |
748 | { | |
749 | Elf64_External_Dyn *dynp = (Elf64_External_Dyn *) buf; | |
433759f7 | 750 | |
b6d7a4bf | 751 | current_dyntag = extract_unsigned_integer ((gdb_byte *) dynp->d_tag, |
e17a4113 UW |
752 | 8, byte_order); |
753 | dyn_ptr = extract_unsigned_integer ((gdb_byte *) dynp->d_un.d_ptr, | |
754 | 8, byte_order); | |
97ec2c2f | 755 | } |
b6d7a4bf | 756 | if (current_dyntag == DT_NULL) |
97ec2c2f UW |
757 | break; |
758 | ||
b6d7a4bf | 759 | if (current_dyntag == desired_dyntag) |
97ec2c2f UW |
760 | { |
761 | if (ptr) | |
762 | *ptr = dyn_ptr; | |
763 | ||
764 | xfree (bufstart); | |
765 | return 1; | |
766 | } | |
767 | } | |
768 | ||
769 | xfree (bufstart); | |
770 | return 0; | |
771 | } | |
772 | ||
7f86f058 PA |
773 | /* Locate the base address of dynamic linker structs for SVR4 elf |
774 | targets. | |
13437d4b KB |
775 | |
776 | For SVR4 elf targets the address of the dynamic linker's runtime | |
777 | structure is contained within the dynamic info section in the | |
778 | executable file. The dynamic section is also mapped into the | |
779 | inferior address space. Because the runtime loader fills in the | |
780 | real address before starting the inferior, we have to read in the | |
781 | dynamic info section from the inferior address space. | |
782 | If there are any errors while trying to find the address, we | |
7f86f058 | 783 | silently return 0, otherwise the found address is returned. */ |
13437d4b KB |
784 | |
785 | static CORE_ADDR | |
786 | elf_locate_base (void) | |
787 | { | |
3b7344d5 | 788 | struct bound_minimal_symbol msymbol; |
3a40aaa0 | 789 | CORE_ADDR dyn_ptr; |
13437d4b | 790 | |
65728c26 DJ |
791 | /* Look for DT_MIPS_RLD_MAP first. MIPS executables use this |
792 | instead of DT_DEBUG, although they sometimes contain an unused | |
793 | DT_DEBUG. */ | |
97ec2c2f UW |
794 | if (scan_dyntag (DT_MIPS_RLD_MAP, exec_bfd, &dyn_ptr) |
795 | || scan_dyntag_auxv (DT_MIPS_RLD_MAP, &dyn_ptr)) | |
3a40aaa0 | 796 | { |
f5656ead | 797 | struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr; |
3a40aaa0 | 798 | gdb_byte *pbuf; |
b6da22b0 | 799 | int pbuf_size = TYPE_LENGTH (ptr_type); |
433759f7 | 800 | |
3a40aaa0 UW |
801 | pbuf = alloca (pbuf_size); |
802 | /* DT_MIPS_RLD_MAP contains a pointer to the address | |
803 | of the dynamic link structure. */ | |
804 | if (target_read_memory (dyn_ptr, pbuf, pbuf_size)) | |
e499d0f1 | 805 | return 0; |
b6da22b0 | 806 | return extract_typed_address (pbuf, ptr_type); |
e499d0f1 DJ |
807 | } |
808 | ||
65728c26 | 809 | /* Find DT_DEBUG. */ |
97ec2c2f UW |
810 | if (scan_dyntag (DT_DEBUG, exec_bfd, &dyn_ptr) |
811 | || scan_dyntag_auxv (DT_DEBUG, &dyn_ptr)) | |
65728c26 DJ |
812 | return dyn_ptr; |
813 | ||
3a40aaa0 UW |
814 | /* This may be a static executable. Look for the symbol |
815 | conventionally named _r_debug, as a last resort. */ | |
816 | msymbol = lookup_minimal_symbol ("_r_debug", NULL, symfile_objfile); | |
3b7344d5 | 817 | if (msymbol.minsym != NULL) |
77e371c0 | 818 | return BMSYMBOL_VALUE_ADDRESS (msymbol); |
13437d4b KB |
819 | |
820 | /* DT_DEBUG entry not found. */ | |
821 | return 0; | |
822 | } | |
823 | ||
7f86f058 | 824 | /* Locate the base address of dynamic linker structs. |
13437d4b KB |
825 | |
826 | For both the SunOS and SVR4 shared library implementations, if the | |
827 | inferior executable has been linked dynamically, there is a single | |
828 | address somewhere in the inferior's data space which is the key to | |
829 | locating all of the dynamic linker's runtime structures. This | |
830 | address is the value of the debug base symbol. The job of this | |
831 | function is to find and return that address, or to return 0 if there | |
832 | is no such address (the executable is statically linked for example). | |
833 | ||
834 | For SunOS, the job is almost trivial, since the dynamic linker and | |
835 | all of it's structures are statically linked to the executable at | |
836 | link time. Thus the symbol for the address we are looking for has | |
837 | already been added to the minimal symbol table for the executable's | |
838 | objfile at the time the symbol file's symbols were read, and all we | |
839 | have to do is look it up there. Note that we explicitly do NOT want | |
840 | to find the copies in the shared library. | |
841 | ||
842 | The SVR4 version is a bit more complicated because the address | |
843 | is contained somewhere in the dynamic info section. We have to go | |
844 | to a lot more work to discover the address of the debug base symbol. | |
845 | Because of this complexity, we cache the value we find and return that | |
846 | value on subsequent invocations. Note there is no copy in the | |
7f86f058 | 847 | executable symbol tables. */ |
13437d4b KB |
848 | |
849 | static CORE_ADDR | |
1a816a87 | 850 | locate_base (struct svr4_info *info) |
13437d4b | 851 | { |
13437d4b KB |
852 | /* Check to see if we have a currently valid address, and if so, avoid |
853 | doing all this work again and just return the cached address. If | |
854 | we have no cached address, try to locate it in the dynamic info | |
d5a921c9 KB |
855 | section for ELF executables. There's no point in doing any of this |
856 | though if we don't have some link map offsets to work with. */ | |
13437d4b | 857 | |
1a816a87 | 858 | if (info->debug_base == 0 && svr4_have_link_map_offsets ()) |
0763ab81 | 859 | info->debug_base = elf_locate_base (); |
1a816a87 | 860 | return info->debug_base; |
13437d4b KB |
861 | } |
862 | ||
e4cd0d6a | 863 | /* Find the first element in the inferior's dynamic link map, and |
6f992fbf JB |
864 | return its address in the inferior. Return zero if the address |
865 | could not be determined. | |
13437d4b | 866 | |
e4cd0d6a MK |
867 | FIXME: Perhaps we should validate the info somehow, perhaps by |
868 | checking r_version for a known version number, or r_state for | |
869 | RT_CONSISTENT. */ | |
13437d4b KB |
870 | |
871 | static CORE_ADDR | |
1a816a87 | 872 | solib_svr4_r_map (struct svr4_info *info) |
13437d4b | 873 | { |
4b188b9f | 874 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); |
f5656ead | 875 | struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr; |
08597104 JB |
876 | CORE_ADDR addr = 0; |
877 | volatile struct gdb_exception ex; | |
13437d4b | 878 | |
08597104 JB |
879 | TRY_CATCH (ex, RETURN_MASK_ERROR) |
880 | { | |
881 | addr = read_memory_typed_address (info->debug_base + lmo->r_map_offset, | |
882 | ptr_type); | |
883 | } | |
884 | exception_print (gdb_stderr, ex); | |
885 | return addr; | |
e4cd0d6a | 886 | } |
13437d4b | 887 | |
7cd25cfc DJ |
888 | /* Find r_brk from the inferior's debug base. */ |
889 | ||
890 | static CORE_ADDR | |
1a816a87 | 891 | solib_svr4_r_brk (struct svr4_info *info) |
7cd25cfc DJ |
892 | { |
893 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); | |
f5656ead | 894 | struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr; |
7cd25cfc | 895 | |
1a816a87 PA |
896 | return read_memory_typed_address (info->debug_base + lmo->r_brk_offset, |
897 | ptr_type); | |
7cd25cfc DJ |
898 | } |
899 | ||
e4cd0d6a MK |
900 | /* Find the link map for the dynamic linker (if it is not in the |
901 | normal list of loaded shared objects). */ | |
13437d4b | 902 | |
e4cd0d6a | 903 | static CORE_ADDR |
1a816a87 | 904 | solib_svr4_r_ldsomap (struct svr4_info *info) |
e4cd0d6a MK |
905 | { |
906 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); | |
f5656ead TT |
907 | struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr; |
908 | enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); | |
e4cd0d6a | 909 | ULONGEST version; |
13437d4b | 910 | |
e4cd0d6a MK |
911 | /* Check version, and return zero if `struct r_debug' doesn't have |
912 | the r_ldsomap member. */ | |
1a816a87 PA |
913 | version |
914 | = read_memory_unsigned_integer (info->debug_base + lmo->r_version_offset, | |
e17a4113 | 915 | lmo->r_version_size, byte_order); |
e4cd0d6a MK |
916 | if (version < 2 || lmo->r_ldsomap_offset == -1) |
917 | return 0; | |
13437d4b | 918 | |
1a816a87 | 919 | return read_memory_typed_address (info->debug_base + lmo->r_ldsomap_offset, |
b6da22b0 | 920 | ptr_type); |
13437d4b KB |
921 | } |
922 | ||
de18c1d8 JM |
923 | /* On Solaris systems with some versions of the dynamic linker, |
924 | ld.so's l_name pointer points to the SONAME in the string table | |
925 | rather than into writable memory. So that GDB can find shared | |
926 | libraries when loading a core file generated by gcore, ensure that | |
927 | memory areas containing the l_name string are saved in the core | |
928 | file. */ | |
929 | ||
930 | static int | |
931 | svr4_keep_data_in_core (CORE_ADDR vaddr, unsigned long size) | |
932 | { | |
933 | struct svr4_info *info; | |
934 | CORE_ADDR ldsomap; | |
935 | struct so_list *new; | |
936 | struct cleanup *old_chain; | |
74de0234 | 937 | CORE_ADDR name_lm; |
de18c1d8 JM |
938 | |
939 | info = get_svr4_info (); | |
940 | ||
941 | info->debug_base = 0; | |
942 | locate_base (info); | |
943 | if (!info->debug_base) | |
944 | return 0; | |
945 | ||
946 | ldsomap = solib_svr4_r_ldsomap (info); | |
947 | if (!ldsomap) | |
948 | return 0; | |
949 | ||
41bf6aca | 950 | new = XCNEW (struct so_list); |
de18c1d8 | 951 | old_chain = make_cleanup (xfree, new); |
3957565a | 952 | new->lm_info = lm_info_read (ldsomap); |
de18c1d8 | 953 | make_cleanup (xfree, new->lm_info); |
3957565a | 954 | name_lm = new->lm_info ? new->lm_info->l_name : 0; |
de18c1d8 JM |
955 | do_cleanups (old_chain); |
956 | ||
74de0234 | 957 | return (name_lm >= vaddr && name_lm < vaddr + size); |
de18c1d8 JM |
958 | } |
959 | ||
7f86f058 | 960 | /* Implement the "open_symbol_file_object" target_so_ops method. |
13437d4b | 961 | |
7f86f058 PA |
962 | If no open symbol file, attempt to locate and open the main symbol |
963 | file. On SVR4 systems, this is the first link map entry. If its | |
964 | name is here, we can open it. Useful when attaching to a process | |
965 | without first loading its symbol file. */ | |
13437d4b KB |
966 | |
967 | static int | |
968 | open_symbol_file_object (void *from_ttyp) | |
969 | { | |
970 | CORE_ADDR lm, l_name; | |
971 | char *filename; | |
972 | int errcode; | |
973 | int from_tty = *(int *)from_ttyp; | |
4b188b9f | 974 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); |
f5656ead | 975 | struct type *ptr_type = builtin_type (target_gdbarch ())->builtin_data_ptr; |
b6da22b0 | 976 | int l_name_size = TYPE_LENGTH (ptr_type); |
cfaefc65 | 977 | gdb_byte *l_name_buf = xmalloc (l_name_size); |
b8c9b27d | 978 | struct cleanup *cleanups = make_cleanup (xfree, l_name_buf); |
6c95b8df | 979 | struct svr4_info *info = get_svr4_info (); |
13437d4b KB |
980 | |
981 | if (symfile_objfile) | |
9e2f0ad4 | 982 | if (!query (_("Attempt to reload symbols from process? "))) |
3bb47e8b TT |
983 | { |
984 | do_cleanups (cleanups); | |
985 | return 0; | |
986 | } | |
13437d4b | 987 | |
7cd25cfc | 988 | /* Always locate the debug struct, in case it has moved. */ |
1a816a87 PA |
989 | info->debug_base = 0; |
990 | if (locate_base (info) == 0) | |
3bb47e8b TT |
991 | { |
992 | do_cleanups (cleanups); | |
993 | return 0; /* failed somehow... */ | |
994 | } | |
13437d4b KB |
995 | |
996 | /* First link map member should be the executable. */ | |
1a816a87 | 997 | lm = solib_svr4_r_map (info); |
e4cd0d6a | 998 | if (lm == 0) |
3bb47e8b TT |
999 | { |
1000 | do_cleanups (cleanups); | |
1001 | return 0; /* failed somehow... */ | |
1002 | } | |
13437d4b KB |
1003 | |
1004 | /* Read address of name from target memory to GDB. */ | |
cfaefc65 | 1005 | read_memory (lm + lmo->l_name_offset, l_name_buf, l_name_size); |
13437d4b | 1006 | |
cfaefc65 | 1007 | /* Convert the address to host format. */ |
b6da22b0 | 1008 | l_name = extract_typed_address (l_name_buf, ptr_type); |
13437d4b | 1009 | |
13437d4b | 1010 | if (l_name == 0) |
3bb47e8b TT |
1011 | { |
1012 | do_cleanups (cleanups); | |
1013 | return 0; /* No filename. */ | |
1014 | } | |
13437d4b KB |
1015 | |
1016 | /* Now fetch the filename from target memory. */ | |
1017 | target_read_string (l_name, &filename, SO_NAME_MAX_PATH_SIZE - 1, &errcode); | |
ea5bf0a1 | 1018 | make_cleanup (xfree, filename); |
13437d4b KB |
1019 | |
1020 | if (errcode) | |
1021 | { | |
8a3fe4f8 | 1022 | warning (_("failed to read exec filename from attached file: %s"), |
13437d4b | 1023 | safe_strerror (errcode)); |
3bb47e8b | 1024 | do_cleanups (cleanups); |
13437d4b KB |
1025 | return 0; |
1026 | } | |
1027 | ||
13437d4b | 1028 | /* Have a pathname: read the symbol file. */ |
1adeb98a | 1029 | symbol_file_add_main (filename, from_tty); |
13437d4b | 1030 | |
3bb47e8b | 1031 | do_cleanups (cleanups); |
13437d4b KB |
1032 | return 1; |
1033 | } | |
13437d4b | 1034 | |
2268b414 JK |
1035 | /* Data exchange structure for the XML parser as returned by |
1036 | svr4_current_sos_via_xfer_libraries. */ | |
1037 | ||
1038 | struct svr4_library_list | |
1039 | { | |
1040 | struct so_list *head, **tailp; | |
1041 | ||
1042 | /* Inferior address of struct link_map used for the main executable. It is | |
1043 | NULL if not known. */ | |
1044 | CORE_ADDR main_lm; | |
1045 | }; | |
1046 | ||
93f2a35e JK |
1047 | /* Implementation for target_so_ops.free_so. */ |
1048 | ||
1049 | static void | |
1050 | svr4_free_so (struct so_list *so) | |
1051 | { | |
1052 | xfree (so->lm_info); | |
1053 | } | |
1054 | ||
0892cb63 DE |
1055 | /* Implement target_so_ops.clear_so. */ |
1056 | ||
1057 | static void | |
1058 | svr4_clear_so (struct so_list *so) | |
1059 | { | |
6dcc1893 PP |
1060 | if (so->lm_info != NULL) |
1061 | so->lm_info->l_addr_p = 0; | |
0892cb63 DE |
1062 | } |
1063 | ||
93f2a35e JK |
1064 | /* Free so_list built so far (called via cleanup). */ |
1065 | ||
1066 | static void | |
1067 | svr4_free_library_list (void *p_list) | |
1068 | { | |
1069 | struct so_list *list = *(struct so_list **) p_list; | |
1070 | ||
1071 | while (list != NULL) | |
1072 | { | |
1073 | struct so_list *next = list->next; | |
1074 | ||
3756ef7e | 1075 | free_so (list); |
93f2a35e JK |
1076 | list = next; |
1077 | } | |
1078 | } | |
1079 | ||
f9e14852 GB |
1080 | /* Copy library list. */ |
1081 | ||
1082 | static struct so_list * | |
1083 | svr4_copy_library_list (struct so_list *src) | |
1084 | { | |
1085 | struct so_list *dst = NULL; | |
1086 | struct so_list **link = &dst; | |
1087 | ||
1088 | while (src != NULL) | |
1089 | { | |
1090 | struct so_list *new; | |
1091 | ||
1092 | new = xmalloc (sizeof (struct so_list)); | |
1093 | memcpy (new, src, sizeof (struct so_list)); | |
1094 | ||
1095 | new->lm_info = xmalloc (sizeof (struct lm_info)); | |
1096 | memcpy (new->lm_info, src->lm_info, sizeof (struct lm_info)); | |
1097 | ||
1098 | new->next = NULL; | |
1099 | *link = new; | |
1100 | link = &new->next; | |
1101 | ||
1102 | src = src->next; | |
1103 | } | |
1104 | ||
1105 | return dst; | |
1106 | } | |
1107 | ||
2268b414 JK |
1108 | #ifdef HAVE_LIBEXPAT |
1109 | ||
1110 | #include "xml-support.h" | |
1111 | ||
1112 | /* Handle the start of a <library> element. Note: new elements are added | |
1113 | at the tail of the list, keeping the list in order. */ | |
1114 | ||
1115 | static void | |
1116 | library_list_start_library (struct gdb_xml_parser *parser, | |
1117 | const struct gdb_xml_element *element, | |
1118 | void *user_data, VEC(gdb_xml_value_s) *attributes) | |
1119 | { | |
1120 | struct svr4_library_list *list = user_data; | |
1121 | const char *name = xml_find_attribute (attributes, "name")->value; | |
1122 | ULONGEST *lmp = xml_find_attribute (attributes, "lm")->value; | |
1123 | ULONGEST *l_addrp = xml_find_attribute (attributes, "l_addr")->value; | |
1124 | ULONGEST *l_ldp = xml_find_attribute (attributes, "l_ld")->value; | |
1125 | struct so_list *new_elem; | |
1126 | ||
41bf6aca TT |
1127 | new_elem = XCNEW (struct so_list); |
1128 | new_elem->lm_info = XCNEW (struct lm_info); | |
2268b414 JK |
1129 | new_elem->lm_info->lm_addr = *lmp; |
1130 | new_elem->lm_info->l_addr_inferior = *l_addrp; | |
1131 | new_elem->lm_info->l_ld = *l_ldp; | |
1132 | ||
1133 | strncpy (new_elem->so_name, name, sizeof (new_elem->so_name) - 1); | |
1134 | new_elem->so_name[sizeof (new_elem->so_name) - 1] = 0; | |
1135 | strcpy (new_elem->so_original_name, new_elem->so_name); | |
1136 | ||
1137 | *list->tailp = new_elem; | |
1138 | list->tailp = &new_elem->next; | |
1139 | } | |
1140 | ||
1141 | /* Handle the start of a <library-list-svr4> element. */ | |
1142 | ||
1143 | static void | |
1144 | svr4_library_list_start_list (struct gdb_xml_parser *parser, | |
1145 | const struct gdb_xml_element *element, | |
1146 | void *user_data, VEC(gdb_xml_value_s) *attributes) | |
1147 | { | |
1148 | struct svr4_library_list *list = user_data; | |
1149 | const char *version = xml_find_attribute (attributes, "version")->value; | |
1150 | struct gdb_xml_value *main_lm = xml_find_attribute (attributes, "main-lm"); | |
1151 | ||
1152 | if (strcmp (version, "1.0") != 0) | |
1153 | gdb_xml_error (parser, | |
1154 | _("SVR4 Library list has unsupported version \"%s\""), | |
1155 | version); | |
1156 | ||
1157 | if (main_lm) | |
1158 | list->main_lm = *(ULONGEST *) main_lm->value; | |
1159 | } | |
1160 | ||
1161 | /* The allowed elements and attributes for an XML library list. | |
1162 | The root element is a <library-list>. */ | |
1163 | ||
1164 | static const struct gdb_xml_attribute svr4_library_attributes[] = | |
1165 | { | |
1166 | { "name", GDB_XML_AF_NONE, NULL, NULL }, | |
1167 | { "lm", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL }, | |
1168 | { "l_addr", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL }, | |
1169 | { "l_ld", GDB_XML_AF_NONE, gdb_xml_parse_attr_ulongest, NULL }, | |
1170 | { NULL, GDB_XML_AF_NONE, NULL, NULL } | |
1171 | }; | |
1172 | ||
1173 | static const struct gdb_xml_element svr4_library_list_children[] = | |
1174 | { | |
1175 | { | |
1176 | "library", svr4_library_attributes, NULL, | |
1177 | GDB_XML_EF_REPEATABLE | GDB_XML_EF_OPTIONAL, | |
1178 | library_list_start_library, NULL | |
1179 | }, | |
1180 | { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL } | |
1181 | }; | |
1182 | ||
1183 | static const struct gdb_xml_attribute svr4_library_list_attributes[] = | |
1184 | { | |
1185 | { "version", GDB_XML_AF_NONE, NULL, NULL }, | |
1186 | { "main-lm", GDB_XML_AF_OPTIONAL, gdb_xml_parse_attr_ulongest, NULL }, | |
1187 | { NULL, GDB_XML_AF_NONE, NULL, NULL } | |
1188 | }; | |
1189 | ||
1190 | static const struct gdb_xml_element svr4_library_list_elements[] = | |
1191 | { | |
1192 | { "library-list-svr4", svr4_library_list_attributes, svr4_library_list_children, | |
1193 | GDB_XML_EF_NONE, svr4_library_list_start_list, NULL }, | |
1194 | { NULL, NULL, NULL, GDB_XML_EF_NONE, NULL, NULL } | |
1195 | }; | |
1196 | ||
2268b414 JK |
1197 | /* Parse qXfer:libraries:read packet into *SO_LIST_RETURN. Return 1 if |
1198 | ||
1199 | Return 0 if packet not supported, *SO_LIST_RETURN is not modified in such | |
1200 | case. Return 1 if *SO_LIST_RETURN contains the library list, it may be | |
1201 | empty, caller is responsible for freeing all its entries. */ | |
1202 | ||
1203 | static int | |
1204 | svr4_parse_libraries (const char *document, struct svr4_library_list *list) | |
1205 | { | |
1206 | struct cleanup *back_to = make_cleanup (svr4_free_library_list, | |
1207 | &list->head); | |
1208 | ||
1209 | memset (list, 0, sizeof (*list)); | |
1210 | list->tailp = &list->head; | |
2eca4a8d | 1211 | if (gdb_xml_parse_quick (_("target library list"), "library-list-svr4.dtd", |
2268b414 JK |
1212 | svr4_library_list_elements, document, list) == 0) |
1213 | { | |
1214 | /* Parsed successfully, keep the result. */ | |
1215 | discard_cleanups (back_to); | |
1216 | return 1; | |
1217 | } | |
1218 | ||
1219 | do_cleanups (back_to); | |
1220 | return 0; | |
1221 | } | |
1222 | ||
f9e14852 | 1223 | /* Attempt to get so_list from target via qXfer:libraries-svr4:read packet. |
2268b414 JK |
1224 | |
1225 | Return 0 if packet not supported, *SO_LIST_RETURN is not modified in such | |
1226 | case. Return 1 if *SO_LIST_RETURN contains the library list, it may be | |
f9e14852 GB |
1227 | empty, caller is responsible for freeing all its entries. |
1228 | ||
1229 | Note that ANNEX must be NULL if the remote does not explicitly allow | |
1230 | qXfer:libraries-svr4:read packets with non-empty annexes. Support for | |
1231 | this can be checked using target_augmented_libraries_svr4_read (). */ | |
2268b414 JK |
1232 | |
1233 | static int | |
f9e14852 GB |
1234 | svr4_current_sos_via_xfer_libraries (struct svr4_library_list *list, |
1235 | const char *annex) | |
2268b414 JK |
1236 | { |
1237 | char *svr4_library_document; | |
1238 | int result; | |
1239 | struct cleanup *back_to; | |
1240 | ||
f9e14852 GB |
1241 | gdb_assert (annex == NULL || target_augmented_libraries_svr4_read ()); |
1242 | ||
2268b414 JK |
1243 | /* Fetch the list of shared libraries. */ |
1244 | svr4_library_document = target_read_stralloc (¤t_target, | |
1245 | TARGET_OBJECT_LIBRARIES_SVR4, | |
f9e14852 | 1246 | annex); |
2268b414 JK |
1247 | if (svr4_library_document == NULL) |
1248 | return 0; | |
1249 | ||
1250 | back_to = make_cleanup (xfree, svr4_library_document); | |
1251 | result = svr4_parse_libraries (svr4_library_document, list); | |
1252 | do_cleanups (back_to); | |
1253 | ||
1254 | return result; | |
1255 | } | |
1256 | ||
1257 | #else | |
1258 | ||
1259 | static int | |
f9e14852 GB |
1260 | svr4_current_sos_via_xfer_libraries (struct svr4_library_list *list, |
1261 | const char *annex) | |
2268b414 JK |
1262 | { |
1263 | return 0; | |
1264 | } | |
1265 | ||
1266 | #endif | |
1267 | ||
34439770 DJ |
1268 | /* If no shared library information is available from the dynamic |
1269 | linker, build a fallback list from other sources. */ | |
1270 | ||
1271 | static struct so_list * | |
1272 | svr4_default_sos (void) | |
1273 | { | |
6c95b8df | 1274 | struct svr4_info *info = get_svr4_info (); |
8e5c319d | 1275 | struct so_list *new; |
1a816a87 | 1276 | |
8e5c319d JK |
1277 | if (!info->debug_loader_offset_p) |
1278 | return NULL; | |
34439770 | 1279 | |
41bf6aca | 1280 | new = XCNEW (struct so_list); |
34439770 | 1281 | |
3957565a | 1282 | new->lm_info = xzalloc (sizeof (struct lm_info)); |
34439770 | 1283 | |
3957565a | 1284 | /* Nothing will ever check the other fields if we set l_addr_p. */ |
8e5c319d | 1285 | new->lm_info->l_addr = info->debug_loader_offset; |
3957565a | 1286 | new->lm_info->l_addr_p = 1; |
34439770 | 1287 | |
8e5c319d JK |
1288 | strncpy (new->so_name, info->debug_loader_name, SO_NAME_MAX_PATH_SIZE - 1); |
1289 | new->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0'; | |
1290 | strcpy (new->so_original_name, new->so_name); | |
34439770 | 1291 | |
8e5c319d | 1292 | return new; |
34439770 DJ |
1293 | } |
1294 | ||
f9e14852 GB |
1295 | /* Read the whole inferior libraries chain starting at address LM. |
1296 | Expect the first entry in the chain's previous entry to be PREV_LM. | |
1297 | Add the entries to the tail referenced by LINK_PTR_PTR. Ignore the | |
1298 | first entry if IGNORE_FIRST and set global MAIN_LM_ADDR according | |
1299 | to it. Returns nonzero upon success. If zero is returned the | |
1300 | entries stored to LINK_PTR_PTR are still valid although they may | |
1301 | represent only part of the inferior library list. */ | |
13437d4b | 1302 | |
f9e14852 GB |
1303 | static int |
1304 | svr4_read_so_list (CORE_ADDR lm, CORE_ADDR prev_lm, | |
1305 | struct so_list ***link_ptr_ptr, int ignore_first) | |
13437d4b | 1306 | { |
c725e7b6 | 1307 | CORE_ADDR first_l_name = 0; |
f9e14852 | 1308 | CORE_ADDR next_lm; |
13437d4b | 1309 | |
cb08cc53 | 1310 | for (; lm != 0; prev_lm = lm, lm = next_lm) |
13437d4b | 1311 | { |
cb08cc53 JK |
1312 | struct so_list *new; |
1313 | struct cleanup *old_chain; | |
1314 | int errcode; | |
1315 | char *buffer; | |
13437d4b | 1316 | |
41bf6aca | 1317 | new = XCNEW (struct so_list); |
cb08cc53 | 1318 | old_chain = make_cleanup_free_so (new); |
13437d4b | 1319 | |
3957565a JK |
1320 | new->lm_info = lm_info_read (lm); |
1321 | if (new->lm_info == NULL) | |
1322 | { | |
1323 | do_cleanups (old_chain); | |
f9e14852 | 1324 | return 0; |
3957565a | 1325 | } |
13437d4b | 1326 | |
3957565a | 1327 | next_lm = new->lm_info->l_next; |
492928e4 | 1328 | |
3957565a | 1329 | if (new->lm_info->l_prev != prev_lm) |
492928e4 | 1330 | { |
2268b414 | 1331 | warning (_("Corrupted shared library list: %s != %s"), |
f5656ead TT |
1332 | paddress (target_gdbarch (), prev_lm), |
1333 | paddress (target_gdbarch (), new->lm_info->l_prev)); | |
cb08cc53 | 1334 | do_cleanups (old_chain); |
f9e14852 | 1335 | return 0; |
492928e4 | 1336 | } |
13437d4b KB |
1337 | |
1338 | /* For SVR4 versions, the first entry in the link map is for the | |
1339 | inferior executable, so we must ignore it. For some versions of | |
1340 | SVR4, it has no name. For others (Solaris 2.3 for example), it | |
1341 | does have a name, so we can no longer use a missing name to | |
c378eb4e | 1342 | decide when to ignore it. */ |
3957565a | 1343 | if (ignore_first && new->lm_info->l_prev == 0) |
93a57060 | 1344 | { |
cb08cc53 JK |
1345 | struct svr4_info *info = get_svr4_info (); |
1346 | ||
c91550fc | 1347 | first_l_name = new->lm_info->l_name; |
1a816a87 | 1348 | info->main_lm_addr = new->lm_info->lm_addr; |
cb08cc53 JK |
1349 | do_cleanups (old_chain); |
1350 | continue; | |
93a57060 | 1351 | } |
13437d4b | 1352 | |
cb08cc53 | 1353 | /* Extract this shared object's name. */ |
3957565a | 1354 | target_read_string (new->lm_info->l_name, &buffer, |
cb08cc53 JK |
1355 | SO_NAME_MAX_PATH_SIZE - 1, &errcode); |
1356 | if (errcode != 0) | |
1357 | { | |
7d760051 UW |
1358 | /* If this entry's l_name address matches that of the |
1359 | inferior executable, then this is not a normal shared | |
1360 | object, but (most likely) a vDSO. In this case, silently | |
1361 | skip it; otherwise emit a warning. */ | |
c91550fc | 1362 | if (first_l_name == 0 || new->lm_info->l_name != first_l_name) |
7d760051 UW |
1363 | warning (_("Can't read pathname for load map: %s."), |
1364 | safe_strerror (errcode)); | |
cb08cc53 JK |
1365 | do_cleanups (old_chain); |
1366 | continue; | |
13437d4b KB |
1367 | } |
1368 | ||
cb08cc53 JK |
1369 | strncpy (new->so_name, buffer, SO_NAME_MAX_PATH_SIZE - 1); |
1370 | new->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0'; | |
1371 | strcpy (new->so_original_name, new->so_name); | |
1372 | xfree (buffer); | |
492928e4 | 1373 | |
cb08cc53 JK |
1374 | /* If this entry has no name, or its name matches the name |
1375 | for the main executable, don't include it in the list. */ | |
1376 | if (! new->so_name[0] || match_main (new->so_name)) | |
492928e4 | 1377 | { |
cb08cc53 JK |
1378 | do_cleanups (old_chain); |
1379 | continue; | |
492928e4 | 1380 | } |
e4cd0d6a | 1381 | |
13437d4b | 1382 | discard_cleanups (old_chain); |
cb08cc53 JK |
1383 | new->next = 0; |
1384 | **link_ptr_ptr = new; | |
1385 | *link_ptr_ptr = &new->next; | |
13437d4b | 1386 | } |
f9e14852 GB |
1387 | |
1388 | return 1; | |
cb08cc53 JK |
1389 | } |
1390 | ||
f9e14852 GB |
1391 | /* Read the full list of currently loaded shared objects directly |
1392 | from the inferior, without referring to any libraries read and | |
1393 | stored by the probes interface. Handle special cases relating | |
1394 | to the first elements of the list. */ | |
cb08cc53 JK |
1395 | |
1396 | static struct so_list * | |
f9e14852 | 1397 | svr4_current_sos_direct (struct svr4_info *info) |
cb08cc53 JK |
1398 | { |
1399 | CORE_ADDR lm; | |
1400 | struct so_list *head = NULL; | |
1401 | struct so_list **link_ptr = &head; | |
cb08cc53 JK |
1402 | struct cleanup *back_to; |
1403 | int ignore_first; | |
2268b414 JK |
1404 | struct svr4_library_list library_list; |
1405 | ||
0c5bf5a9 JK |
1406 | /* Fall back to manual examination of the target if the packet is not |
1407 | supported or gdbserver failed to find DT_DEBUG. gdb.server/solib-list.exp | |
1408 | tests a case where gdbserver cannot find the shared libraries list while | |
1409 | GDB itself is able to find it via SYMFILE_OBJFILE. | |
1410 | ||
1411 | Unfortunately statically linked inferiors will also fall back through this | |
1412 | suboptimal code path. */ | |
1413 | ||
f9e14852 GB |
1414 | info->using_xfer = svr4_current_sos_via_xfer_libraries (&library_list, |
1415 | NULL); | |
1416 | if (info->using_xfer) | |
2268b414 JK |
1417 | { |
1418 | if (library_list.main_lm) | |
f9e14852 | 1419 | info->main_lm_addr = library_list.main_lm; |
2268b414 JK |
1420 | |
1421 | return library_list.head ? library_list.head : svr4_default_sos (); | |
1422 | } | |
cb08cc53 | 1423 | |
cb08cc53 JK |
1424 | /* Always locate the debug struct, in case it has moved. */ |
1425 | info->debug_base = 0; | |
1426 | locate_base (info); | |
1427 | ||
1428 | /* If we can't find the dynamic linker's base structure, this | |
1429 | must not be a dynamically linked executable. Hmm. */ | |
1430 | if (! info->debug_base) | |
1431 | return svr4_default_sos (); | |
1432 | ||
1433 | /* Assume that everything is a library if the dynamic loader was loaded | |
1434 | late by a static executable. */ | |
1435 | if (exec_bfd && bfd_get_section_by_name (exec_bfd, ".dynamic") == NULL) | |
1436 | ignore_first = 0; | |
1437 | else | |
1438 | ignore_first = 1; | |
1439 | ||
1440 | back_to = make_cleanup (svr4_free_library_list, &head); | |
1441 | ||
1442 | /* Walk the inferior's link map list, and build our list of | |
1443 | `struct so_list' nodes. */ | |
1444 | lm = solib_svr4_r_map (info); | |
1445 | if (lm) | |
f9e14852 | 1446 | svr4_read_so_list (lm, 0, &link_ptr, ignore_first); |
cb08cc53 JK |
1447 | |
1448 | /* On Solaris, the dynamic linker is not in the normal list of | |
1449 | shared objects, so make sure we pick it up too. Having | |
1450 | symbol information for the dynamic linker is quite crucial | |
1451 | for skipping dynamic linker resolver code. */ | |
1452 | lm = solib_svr4_r_ldsomap (info); | |
1453 | if (lm) | |
f9e14852 | 1454 | svr4_read_so_list (lm, 0, &link_ptr, 0); |
cb08cc53 JK |
1455 | |
1456 | discard_cleanups (back_to); | |
13437d4b | 1457 | |
34439770 DJ |
1458 | if (head == NULL) |
1459 | return svr4_default_sos (); | |
1460 | ||
13437d4b KB |
1461 | return head; |
1462 | } | |
1463 | ||
8b9a549d PA |
1464 | /* Implement the main part of the "current_sos" target_so_ops |
1465 | method. */ | |
f9e14852 GB |
1466 | |
1467 | static struct so_list * | |
8b9a549d | 1468 | svr4_current_sos_1 (void) |
f9e14852 GB |
1469 | { |
1470 | struct svr4_info *info = get_svr4_info (); | |
1471 | ||
1472 | /* If the solib list has been read and stored by the probes | |
1473 | interface then we return a copy of the stored list. */ | |
1474 | if (info->solib_list != NULL) | |
1475 | return svr4_copy_library_list (info->solib_list); | |
1476 | ||
1477 | /* Otherwise obtain the solib list directly from the inferior. */ | |
1478 | return svr4_current_sos_direct (info); | |
1479 | } | |
1480 | ||
8b9a549d PA |
1481 | /* Implement the "current_sos" target_so_ops method. */ |
1482 | ||
1483 | static struct so_list * | |
1484 | svr4_current_sos (void) | |
1485 | { | |
1486 | struct so_list *so_head = svr4_current_sos_1 (); | |
1487 | struct mem_range vsyscall_range; | |
1488 | ||
1489 | /* Filter out the vDSO module, if present. Its symbol file would | |
1490 | not be found on disk. The vDSO/vsyscall's OBJFILE is instead | |
1491 | managed by symfile-mem.c:add_vsyscall_page. */ | |
1492 | if (gdbarch_vsyscall_range (target_gdbarch (), &vsyscall_range) | |
1493 | && vsyscall_range.length != 0) | |
1494 | { | |
1495 | struct so_list **sop; | |
1496 | ||
1497 | sop = &so_head; | |
1498 | while (*sop != NULL) | |
1499 | { | |
1500 | struct so_list *so = *sop; | |
1501 | ||
1502 | /* We can't simply match the vDSO by starting address alone, | |
1503 | because lm_info->l_addr_inferior (and also l_addr) do not | |
1504 | necessarily represent the real starting address of the | |
1505 | ELF if the vDSO's ELF itself is "prelinked". The l_ld | |
1506 | field (the ".dynamic" section of the shared object) | |
1507 | always points at the absolute/resolved address though. | |
1508 | So check whether that address is inside the vDSO's | |
1509 | mapping instead. | |
1510 | ||
1511 | E.g., on Linux 3.16 (x86_64) the vDSO is a regular | |
1512 | 0-based ELF, and we see: | |
1513 | ||
1514 | (gdb) info auxv | |
1515 | 33 AT_SYSINFO_EHDR System-supplied DSO's ELF header 0x7ffff7ffb000 | |
1516 | (gdb) p/x *_r_debug.r_map.l_next | |
1517 | $1 = {l_addr = 0x7ffff7ffb000, ..., l_ld = 0x7ffff7ffb318, ...} | |
1518 | ||
1519 | And on Linux 2.6.32 (x86_64) we see: | |
1520 | ||
1521 | (gdb) info auxv | |
1522 | 33 AT_SYSINFO_EHDR System-supplied DSO's ELF header 0x7ffff7ffe000 | |
1523 | (gdb) p/x *_r_debug.r_map.l_next | |
1524 | $5 = {l_addr = 0x7ffff88fe000, ..., l_ld = 0x7ffff7ffe580, ... } | |
1525 | ||
1526 | Dumping that vDSO shows: | |
1527 | ||
1528 | (gdb) info proc mappings | |
1529 | 0x7ffff7ffe000 0x7ffff7fff000 0x1000 0 [vdso] | |
1530 | (gdb) dump memory vdso.bin 0x7ffff7ffe000 0x7ffff7fff000 | |
1531 | # readelf -Wa vdso.bin | |
1532 | [...] | |
1533 | Entry point address: 0xffffffffff700700 | |
1534 | [...] | |
1535 | Section Headers: | |
1536 | [Nr] Name Type Address Off Size | |
1537 | [ 0] NULL 0000000000000000 000000 000000 | |
1538 | [ 1] .hash HASH ffffffffff700120 000120 000038 | |
1539 | [ 2] .dynsym DYNSYM ffffffffff700158 000158 0000d8 | |
1540 | [...] | |
1541 | [ 9] .dynamic DYNAMIC ffffffffff700580 000580 0000f0 | |
1542 | */ | |
1543 | if (address_in_mem_range (so->lm_info->l_ld, &vsyscall_range)) | |
1544 | { | |
1545 | *sop = so->next; | |
1546 | free_so (so); | |
1547 | break; | |
1548 | } | |
1549 | ||
1550 | sop = &so->next; | |
1551 | } | |
1552 | } | |
1553 | ||
1554 | return so_head; | |
1555 | } | |
1556 | ||
93a57060 | 1557 | /* Get the address of the link_map for a given OBJFILE. */ |
bc4a16ae EZ |
1558 | |
1559 | CORE_ADDR | |
1560 | svr4_fetch_objfile_link_map (struct objfile *objfile) | |
1561 | { | |
93a57060 | 1562 | struct so_list *so; |
6c95b8df | 1563 | struct svr4_info *info = get_svr4_info (); |
bc4a16ae | 1564 | |
93a57060 | 1565 | /* Cause svr4_current_sos() to be run if it hasn't been already. */ |
1a816a87 | 1566 | if (info->main_lm_addr == 0) |
93a57060 | 1567 | solib_add (NULL, 0, ¤t_target, auto_solib_add); |
bc4a16ae | 1568 | |
93a57060 DJ |
1569 | /* svr4_current_sos() will set main_lm_addr for the main executable. */ |
1570 | if (objfile == symfile_objfile) | |
1a816a87 | 1571 | return info->main_lm_addr; |
93a57060 DJ |
1572 | |
1573 | /* The other link map addresses may be found by examining the list | |
1574 | of shared libraries. */ | |
1575 | for (so = master_so_list (); so; so = so->next) | |
1576 | if (so->objfile == objfile) | |
1577 | return so->lm_info->lm_addr; | |
1578 | ||
1579 | /* Not found! */ | |
bc4a16ae EZ |
1580 | return 0; |
1581 | } | |
13437d4b KB |
1582 | |
1583 | /* On some systems, the only way to recognize the link map entry for | |
1584 | the main executable file is by looking at its name. Return | |
1585 | non-zero iff SONAME matches one of the known main executable names. */ | |
1586 | ||
1587 | static int | |
bc043ef3 | 1588 | match_main (const char *soname) |
13437d4b | 1589 | { |
bc043ef3 | 1590 | const char * const *mainp; |
13437d4b KB |
1591 | |
1592 | for (mainp = main_name_list; *mainp != NULL; mainp++) | |
1593 | { | |
1594 | if (strcmp (soname, *mainp) == 0) | |
1595 | return (1); | |
1596 | } | |
1597 | ||
1598 | return (0); | |
1599 | } | |
1600 | ||
13437d4b KB |
1601 | /* Return 1 if PC lies in the dynamic symbol resolution code of the |
1602 | SVR4 run time loader. */ | |
13437d4b | 1603 | |
7d522c90 | 1604 | int |
d7fa2ae2 | 1605 | svr4_in_dynsym_resolve_code (CORE_ADDR pc) |
13437d4b | 1606 | { |
6c95b8df PA |
1607 | struct svr4_info *info = get_svr4_info (); |
1608 | ||
1609 | return ((pc >= info->interp_text_sect_low | |
1610 | && pc < info->interp_text_sect_high) | |
1611 | || (pc >= info->interp_plt_sect_low | |
1612 | && pc < info->interp_plt_sect_high) | |
3e5d3a5a | 1613 | || in_plt_section (pc) |
0875794a | 1614 | || in_gnu_ifunc_stub (pc)); |
13437d4b | 1615 | } |
13437d4b | 1616 | |
2f4950cd AC |
1617 | /* Given an executable's ABFD and target, compute the entry-point |
1618 | address. */ | |
1619 | ||
1620 | static CORE_ADDR | |
1621 | exec_entry_point (struct bfd *abfd, struct target_ops *targ) | |
1622 | { | |
8c2b9656 YQ |
1623 | CORE_ADDR addr; |
1624 | ||
2f4950cd AC |
1625 | /* KevinB wrote ... for most targets, the address returned by |
1626 | bfd_get_start_address() is the entry point for the start | |
1627 | function. But, for some targets, bfd_get_start_address() returns | |
1628 | the address of a function descriptor from which the entry point | |
1629 | address may be extracted. This address is extracted by | |
1630 | gdbarch_convert_from_func_ptr_addr(). The method | |
1631 | gdbarch_convert_from_func_ptr_addr() is the merely the identify | |
1632 | function for targets which don't use function descriptors. */ | |
8c2b9656 | 1633 | addr = gdbarch_convert_from_func_ptr_addr (target_gdbarch (), |
2f4950cd AC |
1634 | bfd_get_start_address (abfd), |
1635 | targ); | |
8c2b9656 | 1636 | return gdbarch_addr_bits_remove (target_gdbarch (), addr); |
2f4950cd | 1637 | } |
13437d4b | 1638 | |
f9e14852 GB |
1639 | /* A probe and its associated action. */ |
1640 | ||
1641 | struct probe_and_action | |
1642 | { | |
1643 | /* The probe. */ | |
1644 | struct probe *probe; | |
1645 | ||
729662a5 TT |
1646 | /* The relocated address of the probe. */ |
1647 | CORE_ADDR address; | |
1648 | ||
f9e14852 GB |
1649 | /* The action. */ |
1650 | enum probe_action action; | |
1651 | }; | |
1652 | ||
1653 | /* Returns a hash code for the probe_and_action referenced by p. */ | |
1654 | ||
1655 | static hashval_t | |
1656 | hash_probe_and_action (const void *p) | |
1657 | { | |
1658 | const struct probe_and_action *pa = p; | |
1659 | ||
729662a5 | 1660 | return (hashval_t) pa->address; |
f9e14852 GB |
1661 | } |
1662 | ||
1663 | /* Returns non-zero if the probe_and_actions referenced by p1 and p2 | |
1664 | are equal. */ | |
1665 | ||
1666 | static int | |
1667 | equal_probe_and_action (const void *p1, const void *p2) | |
1668 | { | |
1669 | const struct probe_and_action *pa1 = p1; | |
1670 | const struct probe_and_action *pa2 = p2; | |
1671 | ||
729662a5 | 1672 | return pa1->address == pa2->address; |
f9e14852 GB |
1673 | } |
1674 | ||
1675 | /* Register a solib event probe and its associated action in the | |
1676 | probes table. */ | |
1677 | ||
1678 | static void | |
729662a5 TT |
1679 | register_solib_event_probe (struct probe *probe, CORE_ADDR address, |
1680 | enum probe_action action) | |
f9e14852 GB |
1681 | { |
1682 | struct svr4_info *info = get_svr4_info (); | |
1683 | struct probe_and_action lookup, *pa; | |
1684 | void **slot; | |
1685 | ||
1686 | /* Create the probes table, if necessary. */ | |
1687 | if (info->probes_table == NULL) | |
1688 | info->probes_table = htab_create_alloc (1, hash_probe_and_action, | |
1689 | equal_probe_and_action, | |
1690 | xfree, xcalloc, xfree); | |
1691 | ||
1692 | lookup.probe = probe; | |
729662a5 | 1693 | lookup.address = address; |
f9e14852 GB |
1694 | slot = htab_find_slot (info->probes_table, &lookup, INSERT); |
1695 | gdb_assert (*slot == HTAB_EMPTY_ENTRY); | |
1696 | ||
1697 | pa = XCNEW (struct probe_and_action); | |
1698 | pa->probe = probe; | |
729662a5 | 1699 | pa->address = address; |
f9e14852 GB |
1700 | pa->action = action; |
1701 | ||
1702 | *slot = pa; | |
1703 | } | |
1704 | ||
1705 | /* Get the solib event probe at the specified location, and the | |
1706 | action associated with it. Returns NULL if no solib event probe | |
1707 | was found. */ | |
1708 | ||
1709 | static struct probe_and_action * | |
1710 | solib_event_probe_at (struct svr4_info *info, CORE_ADDR address) | |
1711 | { | |
f9e14852 GB |
1712 | struct probe_and_action lookup; |
1713 | void **slot; | |
1714 | ||
729662a5 | 1715 | lookup.address = address; |
f9e14852 GB |
1716 | slot = htab_find_slot (info->probes_table, &lookup, NO_INSERT); |
1717 | ||
1718 | if (slot == NULL) | |
1719 | return NULL; | |
1720 | ||
1721 | return (struct probe_and_action *) *slot; | |
1722 | } | |
1723 | ||
1724 | /* Decide what action to take when the specified solib event probe is | |
1725 | hit. */ | |
1726 | ||
1727 | static enum probe_action | |
1728 | solib_event_probe_action (struct probe_and_action *pa) | |
1729 | { | |
1730 | enum probe_action action; | |
1731 | unsigned probe_argc; | |
08a6411c | 1732 | struct frame_info *frame = get_current_frame (); |
f9e14852 GB |
1733 | |
1734 | action = pa->action; | |
1735 | if (action == DO_NOTHING || action == PROBES_INTERFACE_FAILED) | |
1736 | return action; | |
1737 | ||
1738 | gdb_assert (action == FULL_RELOAD || action == UPDATE_OR_RELOAD); | |
1739 | ||
1740 | /* Check that an appropriate number of arguments has been supplied. | |
1741 | We expect: | |
1742 | arg0: Lmid_t lmid (mandatory) | |
1743 | arg1: struct r_debug *debug_base (mandatory) | |
1744 | arg2: struct link_map *new (optional, for incremental updates) */ | |
08a6411c | 1745 | probe_argc = get_probe_argument_count (pa->probe, frame); |
f9e14852 GB |
1746 | if (probe_argc == 2) |
1747 | action = FULL_RELOAD; | |
1748 | else if (probe_argc < 2) | |
1749 | action = PROBES_INTERFACE_FAILED; | |
1750 | ||
1751 | return action; | |
1752 | } | |
1753 | ||
1754 | /* Populate the shared object list by reading the entire list of | |
1755 | shared objects from the inferior. Handle special cases relating | |
1756 | to the first elements of the list. Returns nonzero on success. */ | |
1757 | ||
1758 | static int | |
1759 | solist_update_full (struct svr4_info *info) | |
1760 | { | |
1761 | free_solib_list (info); | |
1762 | info->solib_list = svr4_current_sos_direct (info); | |
1763 | ||
1764 | return 1; | |
1765 | } | |
1766 | ||
1767 | /* Update the shared object list starting from the link-map entry | |
1768 | passed by the linker in the probe's third argument. Returns | |
1769 | nonzero if the list was successfully updated, or zero to indicate | |
1770 | failure. */ | |
1771 | ||
1772 | static int | |
1773 | solist_update_incremental (struct svr4_info *info, CORE_ADDR lm) | |
1774 | { | |
1775 | struct so_list *tail; | |
1776 | CORE_ADDR prev_lm; | |
1777 | ||
1778 | /* svr4_current_sos_direct contains logic to handle a number of | |
1779 | special cases relating to the first elements of the list. To | |
1780 | avoid duplicating this logic we defer to solist_update_full | |
1781 | if the list is empty. */ | |
1782 | if (info->solib_list == NULL) | |
1783 | return 0; | |
1784 | ||
1785 | /* Fall back to a full update if we are using a remote target | |
1786 | that does not support incremental transfers. */ | |
1787 | if (info->using_xfer && !target_augmented_libraries_svr4_read ()) | |
1788 | return 0; | |
1789 | ||
1790 | /* Walk to the end of the list. */ | |
1791 | for (tail = info->solib_list; tail->next != NULL; tail = tail->next) | |
1792 | /* Nothing. */; | |
1793 | prev_lm = tail->lm_info->lm_addr; | |
1794 | ||
1795 | /* Read the new objects. */ | |
1796 | if (info->using_xfer) | |
1797 | { | |
1798 | struct svr4_library_list library_list; | |
1799 | char annex[64]; | |
1800 | ||
1801 | xsnprintf (annex, sizeof (annex), "start=%s;prev=%s", | |
1802 | phex_nz (lm, sizeof (lm)), | |
1803 | phex_nz (prev_lm, sizeof (prev_lm))); | |
1804 | if (!svr4_current_sos_via_xfer_libraries (&library_list, annex)) | |
1805 | return 0; | |
1806 | ||
1807 | tail->next = library_list.head; | |
1808 | } | |
1809 | else | |
1810 | { | |
1811 | struct so_list **link = &tail->next; | |
1812 | ||
1813 | /* IGNORE_FIRST may safely be set to zero here because the | |
1814 | above check and deferral to solist_update_full ensures | |
1815 | that this call to svr4_read_so_list will never see the | |
1816 | first element. */ | |
1817 | if (!svr4_read_so_list (lm, prev_lm, &link, 0)) | |
1818 | return 0; | |
1819 | } | |
1820 | ||
1821 | return 1; | |
1822 | } | |
1823 | ||
1824 | /* Disable the probes-based linker interface and revert to the | |
1825 | original interface. We don't reset the breakpoints as the | |
1826 | ones set up for the probes-based interface are adequate. */ | |
1827 | ||
1828 | static void | |
1829 | disable_probes_interface_cleanup (void *arg) | |
1830 | { | |
1831 | struct svr4_info *info = get_svr4_info (); | |
1832 | ||
1833 | warning (_("Probes-based dynamic linker interface failed.\n" | |
1834 | "Reverting to original interface.\n")); | |
1835 | ||
1836 | free_probes_table (info); | |
1837 | free_solib_list (info); | |
1838 | } | |
1839 | ||
1840 | /* Update the solib list as appropriate when using the | |
1841 | probes-based linker interface. Do nothing if using the | |
1842 | standard interface. */ | |
1843 | ||
1844 | static void | |
1845 | svr4_handle_solib_event (void) | |
1846 | { | |
1847 | struct svr4_info *info = get_svr4_info (); | |
1848 | struct probe_and_action *pa; | |
1849 | enum probe_action action; | |
1850 | struct cleanup *old_chain, *usm_chain; | |
1851 | struct value *val; | |
1852 | CORE_ADDR pc, debug_base, lm = 0; | |
1853 | int is_initial_ns; | |
08a6411c | 1854 | struct frame_info *frame = get_current_frame (); |
f9e14852 GB |
1855 | |
1856 | /* Do nothing if not using the probes interface. */ | |
1857 | if (info->probes_table == NULL) | |
1858 | return; | |
1859 | ||
1860 | /* If anything goes wrong we revert to the original linker | |
1861 | interface. */ | |
1862 | old_chain = make_cleanup (disable_probes_interface_cleanup, NULL); | |
1863 | ||
1864 | pc = regcache_read_pc (get_current_regcache ()); | |
1865 | pa = solib_event_probe_at (info, pc); | |
1866 | if (pa == NULL) | |
1867 | { | |
1868 | do_cleanups (old_chain); | |
1869 | return; | |
1870 | } | |
1871 | ||
1872 | action = solib_event_probe_action (pa); | |
1873 | if (action == PROBES_INTERFACE_FAILED) | |
1874 | { | |
1875 | do_cleanups (old_chain); | |
1876 | return; | |
1877 | } | |
1878 | ||
1879 | if (action == DO_NOTHING) | |
1880 | { | |
1881 | discard_cleanups (old_chain); | |
1882 | return; | |
1883 | } | |
1884 | ||
1885 | /* evaluate_probe_argument looks up symbols in the dynamic linker | |
1886 | using find_pc_section. find_pc_section is accelerated by a cache | |
1887 | called the section map. The section map is invalidated every | |
1888 | time a shared library is loaded or unloaded, and if the inferior | |
1889 | is generating a lot of shared library events then the section map | |
1890 | will be updated every time svr4_handle_solib_event is called. | |
1891 | We called find_pc_section in svr4_create_solib_event_breakpoints, | |
1892 | so we can guarantee that the dynamic linker's sections are in the | |
1893 | section map. We can therefore inhibit section map updates across | |
1894 | these calls to evaluate_probe_argument and save a lot of time. */ | |
1895 | inhibit_section_map_updates (current_program_space); | |
1896 | usm_chain = make_cleanup (resume_section_map_updates_cleanup, | |
1897 | current_program_space); | |
1898 | ||
08a6411c | 1899 | val = evaluate_probe_argument (pa->probe, 1, frame); |
f9e14852 GB |
1900 | if (val == NULL) |
1901 | { | |
1902 | do_cleanups (old_chain); | |
1903 | return; | |
1904 | } | |
1905 | ||
1906 | debug_base = value_as_address (val); | |
1907 | if (debug_base == 0) | |
1908 | { | |
1909 | do_cleanups (old_chain); | |
1910 | return; | |
1911 | } | |
1912 | ||
1913 | /* Always locate the debug struct, in case it moved. */ | |
1914 | info->debug_base = 0; | |
1915 | if (locate_base (info) == 0) | |
1916 | { | |
1917 | do_cleanups (old_chain); | |
1918 | return; | |
1919 | } | |
1920 | ||
1921 | /* GDB does not currently support libraries loaded via dlmopen | |
1922 | into namespaces other than the initial one. We must ignore | |
1923 | any namespace other than the initial namespace here until | |
1924 | support for this is added to GDB. */ | |
1925 | if (debug_base != info->debug_base) | |
1926 | action = DO_NOTHING; | |
1927 | ||
1928 | if (action == UPDATE_OR_RELOAD) | |
1929 | { | |
08a6411c | 1930 | val = evaluate_probe_argument (pa->probe, 2, frame); |
f9e14852 GB |
1931 | if (val != NULL) |
1932 | lm = value_as_address (val); | |
1933 | ||
1934 | if (lm == 0) | |
1935 | action = FULL_RELOAD; | |
1936 | } | |
1937 | ||
1938 | /* Resume section map updates. */ | |
1939 | do_cleanups (usm_chain); | |
1940 | ||
1941 | if (action == UPDATE_OR_RELOAD) | |
1942 | { | |
1943 | if (!solist_update_incremental (info, lm)) | |
1944 | action = FULL_RELOAD; | |
1945 | } | |
1946 | ||
1947 | if (action == FULL_RELOAD) | |
1948 | { | |
1949 | if (!solist_update_full (info)) | |
1950 | { | |
1951 | do_cleanups (old_chain); | |
1952 | return; | |
1953 | } | |
1954 | } | |
1955 | ||
1956 | discard_cleanups (old_chain); | |
1957 | } | |
1958 | ||
1959 | /* Helper function for svr4_update_solib_event_breakpoints. */ | |
1960 | ||
1961 | static int | |
1962 | svr4_update_solib_event_breakpoint (struct breakpoint *b, void *arg) | |
1963 | { | |
1964 | struct bp_location *loc; | |
1965 | ||
1966 | if (b->type != bp_shlib_event) | |
1967 | { | |
1968 | /* Continue iterating. */ | |
1969 | return 0; | |
1970 | } | |
1971 | ||
1972 | for (loc = b->loc; loc != NULL; loc = loc->next) | |
1973 | { | |
1974 | struct svr4_info *info; | |
1975 | struct probe_and_action *pa; | |
1976 | ||
1977 | info = program_space_data (loc->pspace, solib_svr4_pspace_data); | |
1978 | if (info == NULL || info->probes_table == NULL) | |
1979 | continue; | |
1980 | ||
1981 | pa = solib_event_probe_at (info, loc->address); | |
1982 | if (pa == NULL) | |
1983 | continue; | |
1984 | ||
1985 | if (pa->action == DO_NOTHING) | |
1986 | { | |
1987 | if (b->enable_state == bp_disabled && stop_on_solib_events) | |
1988 | enable_breakpoint (b); | |
1989 | else if (b->enable_state == bp_enabled && !stop_on_solib_events) | |
1990 | disable_breakpoint (b); | |
1991 | } | |
1992 | ||
1993 | break; | |
1994 | } | |
1995 | ||
1996 | /* Continue iterating. */ | |
1997 | return 0; | |
1998 | } | |
1999 | ||
2000 | /* Enable or disable optional solib event breakpoints as appropriate. | |
2001 | Called whenever stop_on_solib_events is changed. */ | |
2002 | ||
2003 | static void | |
2004 | svr4_update_solib_event_breakpoints (void) | |
2005 | { | |
2006 | iterate_over_breakpoints (svr4_update_solib_event_breakpoint, NULL); | |
2007 | } | |
2008 | ||
2009 | /* Create and register solib event breakpoints. PROBES is an array | |
2010 | of NUM_PROBES elements, each of which is vector of probes. A | |
2011 | solib event breakpoint will be created and registered for each | |
2012 | probe. */ | |
2013 | ||
2014 | static void | |
2015 | svr4_create_probe_breakpoints (struct gdbarch *gdbarch, | |
729662a5 TT |
2016 | VEC (probe_p) **probes, |
2017 | struct objfile *objfile) | |
f9e14852 GB |
2018 | { |
2019 | int i; | |
2020 | ||
2021 | for (i = 0; i < NUM_PROBES; i++) | |
2022 | { | |
2023 | enum probe_action action = probe_info[i].action; | |
2024 | struct probe *probe; | |
2025 | int ix; | |
2026 | ||
2027 | for (ix = 0; | |
2028 | VEC_iterate (probe_p, probes[i], ix, probe); | |
2029 | ++ix) | |
2030 | { | |
729662a5 TT |
2031 | CORE_ADDR address = get_probe_address (probe, objfile); |
2032 | ||
2033 | create_solib_event_breakpoint (gdbarch, address); | |
2034 | register_solib_event_probe (probe, address, action); | |
f9e14852 GB |
2035 | } |
2036 | } | |
2037 | ||
2038 | svr4_update_solib_event_breakpoints (); | |
2039 | } | |
2040 | ||
2041 | /* Both the SunOS and the SVR4 dynamic linkers call a marker function | |
2042 | before and after mapping and unmapping shared libraries. The sole | |
2043 | purpose of this method is to allow debuggers to set a breakpoint so | |
2044 | they can track these changes. | |
2045 | ||
2046 | Some versions of the glibc dynamic linker contain named probes | |
2047 | to allow more fine grained stopping. Given the address of the | |
2048 | original marker function, this function attempts to find these | |
2049 | probes, and if found, sets breakpoints on those instead. If the | |
2050 | probes aren't found, a single breakpoint is set on the original | |
2051 | marker function. */ | |
2052 | ||
2053 | static void | |
2054 | svr4_create_solib_event_breakpoints (struct gdbarch *gdbarch, | |
2055 | CORE_ADDR address) | |
2056 | { | |
2057 | struct obj_section *os; | |
2058 | ||
2059 | os = find_pc_section (address); | |
2060 | if (os != NULL) | |
2061 | { | |
2062 | int with_prefix; | |
2063 | ||
2064 | for (with_prefix = 0; with_prefix <= 1; with_prefix++) | |
2065 | { | |
2066 | VEC (probe_p) *probes[NUM_PROBES]; | |
2067 | int all_probes_found = 1; | |
25f9533e | 2068 | int checked_can_use_probe_arguments = 0; |
f9e14852 GB |
2069 | int i; |
2070 | ||
2071 | memset (probes, 0, sizeof (probes)); | |
2072 | for (i = 0; i < NUM_PROBES; i++) | |
2073 | { | |
2074 | const char *name = probe_info[i].name; | |
25f9533e | 2075 | struct probe *p; |
f9e14852 GB |
2076 | char buf[32]; |
2077 | ||
2078 | /* Fedora 17 and Red Hat Enterprise Linux 6.2-6.4 | |
2079 | shipped with an early version of the probes code in | |
2080 | which the probes' names were prefixed with "rtld_" | |
2081 | and the "map_failed" probe did not exist. The | |
2082 | locations of the probes are otherwise the same, so | |
2083 | we check for probes with prefixed names if probes | |
2084 | with unprefixed names are not present. */ | |
2085 | if (with_prefix) | |
2086 | { | |
2087 | xsnprintf (buf, sizeof (buf), "rtld_%s", name); | |
2088 | name = buf; | |
2089 | } | |
2090 | ||
2091 | probes[i] = find_probes_in_objfile (os->objfile, "rtld", name); | |
2092 | ||
2093 | /* The "map_failed" probe did not exist in early | |
2094 | versions of the probes code in which the probes' | |
2095 | names were prefixed with "rtld_". */ | |
2096 | if (strcmp (name, "rtld_map_failed") == 0) | |
2097 | continue; | |
2098 | ||
2099 | if (VEC_empty (probe_p, probes[i])) | |
2100 | { | |
2101 | all_probes_found = 0; | |
2102 | break; | |
2103 | } | |
25f9533e SDJ |
2104 | |
2105 | /* Ensure probe arguments can be evaluated. */ | |
2106 | if (!checked_can_use_probe_arguments) | |
2107 | { | |
2108 | p = VEC_index (probe_p, probes[i], 0); | |
2109 | if (!can_evaluate_probe_arguments (p)) | |
2110 | { | |
2111 | all_probes_found = 0; | |
2112 | break; | |
2113 | } | |
2114 | checked_can_use_probe_arguments = 1; | |
2115 | } | |
f9e14852 GB |
2116 | } |
2117 | ||
2118 | if (all_probes_found) | |
729662a5 | 2119 | svr4_create_probe_breakpoints (gdbarch, probes, os->objfile); |
f9e14852 GB |
2120 | |
2121 | for (i = 0; i < NUM_PROBES; i++) | |
2122 | VEC_free (probe_p, probes[i]); | |
2123 | ||
2124 | if (all_probes_found) | |
2125 | return; | |
2126 | } | |
2127 | } | |
2128 | ||
2129 | create_solib_event_breakpoint (gdbarch, address); | |
2130 | } | |
2131 | ||
cb457ae2 YQ |
2132 | /* Helper function for gdb_bfd_lookup_symbol. */ |
2133 | ||
2134 | static int | |
2135 | cmp_name_and_sec_flags (asymbol *sym, void *data) | |
2136 | { | |
2137 | return (strcmp (sym->name, (const char *) data) == 0 | |
2138 | && (sym->section->flags & (SEC_CODE | SEC_DATA)) != 0); | |
2139 | } | |
7f86f058 | 2140 | /* Arrange for dynamic linker to hit breakpoint. |
13437d4b KB |
2141 | |
2142 | Both the SunOS and the SVR4 dynamic linkers have, as part of their | |
2143 | debugger interface, support for arranging for the inferior to hit | |
2144 | a breakpoint after mapping in the shared libraries. This function | |
2145 | enables that breakpoint. | |
2146 | ||
2147 | For SunOS, there is a special flag location (in_debugger) which we | |
2148 | set to 1. When the dynamic linker sees this flag set, it will set | |
2149 | a breakpoint at a location known only to itself, after saving the | |
2150 | original contents of that place and the breakpoint address itself, | |
2151 | in it's own internal structures. When we resume the inferior, it | |
2152 | will eventually take a SIGTRAP when it runs into the breakpoint. | |
2153 | We handle this (in a different place) by restoring the contents of | |
2154 | the breakpointed location (which is only known after it stops), | |
2155 | chasing around to locate the shared libraries that have been | |
2156 | loaded, then resuming. | |
2157 | ||
2158 | For SVR4, the debugger interface structure contains a member (r_brk) | |
2159 | which is statically initialized at the time the shared library is | |
2160 | built, to the offset of a function (_r_debug_state) which is guaran- | |
2161 | teed to be called once before mapping in a library, and again when | |
2162 | the mapping is complete. At the time we are examining this member, | |
2163 | it contains only the unrelocated offset of the function, so we have | |
2164 | to do our own relocation. Later, when the dynamic linker actually | |
2165 | runs, it relocates r_brk to be the actual address of _r_debug_state(). | |
2166 | ||
2167 | The debugger interface structure also contains an enumeration which | |
2168 | is set to either RT_ADD or RT_DELETE prior to changing the mapping, | |
2169 | depending upon whether or not the library is being mapped or unmapped, | |
7f86f058 | 2170 | and then set to RT_CONSISTENT after the library is mapped/unmapped. */ |
13437d4b KB |
2171 | |
2172 | static int | |
268a4a75 | 2173 | enable_break (struct svr4_info *info, int from_tty) |
13437d4b | 2174 | { |
3b7344d5 | 2175 | struct bound_minimal_symbol msymbol; |
bc043ef3 | 2176 | const char * const *bkpt_namep; |
13437d4b | 2177 | asection *interp_sect; |
001f13d8 | 2178 | char *interp_name; |
7cd25cfc | 2179 | CORE_ADDR sym_addr; |
13437d4b | 2180 | |
6c95b8df PA |
2181 | info->interp_text_sect_low = info->interp_text_sect_high = 0; |
2182 | info->interp_plt_sect_low = info->interp_plt_sect_high = 0; | |
13437d4b | 2183 | |
7cd25cfc DJ |
2184 | /* If we already have a shared library list in the target, and |
2185 | r_debug contains r_brk, set the breakpoint there - this should | |
2186 | mean r_brk has already been relocated. Assume the dynamic linker | |
2187 | is the object containing r_brk. */ | |
2188 | ||
268a4a75 | 2189 | solib_add (NULL, from_tty, ¤t_target, auto_solib_add); |
7cd25cfc | 2190 | sym_addr = 0; |
1a816a87 PA |
2191 | if (info->debug_base && solib_svr4_r_map (info) != 0) |
2192 | sym_addr = solib_svr4_r_brk (info); | |
7cd25cfc DJ |
2193 | |
2194 | if (sym_addr != 0) | |
2195 | { | |
2196 | struct obj_section *os; | |
2197 | ||
b36ec657 | 2198 | sym_addr = gdbarch_addr_bits_remove |
f5656ead | 2199 | (target_gdbarch (), gdbarch_convert_from_func_ptr_addr (target_gdbarch (), |
3e43a32a MS |
2200 | sym_addr, |
2201 | ¤t_target)); | |
b36ec657 | 2202 | |
48379de6 DE |
2203 | /* On at least some versions of Solaris there's a dynamic relocation |
2204 | on _r_debug.r_brk and SYM_ADDR may not be relocated yet, e.g., if | |
2205 | we get control before the dynamic linker has self-relocated. | |
2206 | Check if SYM_ADDR is in a known section, if it is assume we can | |
2207 | trust its value. This is just a heuristic though, it could go away | |
2208 | or be replaced if it's getting in the way. | |
2209 | ||
2210 | On ARM we need to know whether the ISA of rtld_db_dlactivity (or | |
2211 | however it's spelled in your particular system) is ARM or Thumb. | |
2212 | That knowledge is encoded in the address, if it's Thumb the low bit | |
2213 | is 1. However, we've stripped that info above and it's not clear | |
2214 | what all the consequences are of passing a non-addr_bits_remove'd | |
f9e14852 | 2215 | address to svr4_create_solib_event_breakpoints. The call to |
48379de6 DE |
2216 | find_pc_section verifies we know about the address and have some |
2217 | hope of computing the right kind of breakpoint to use (via | |
2218 | symbol info). It does mean that GDB needs to be pointed at a | |
2219 | non-stripped version of the dynamic linker in order to obtain | |
2220 | information it already knows about. Sigh. */ | |
2221 | ||
7cd25cfc DJ |
2222 | os = find_pc_section (sym_addr); |
2223 | if (os != NULL) | |
2224 | { | |
2225 | /* Record the relocated start and end address of the dynamic linker | |
2226 | text and plt section for svr4_in_dynsym_resolve_code. */ | |
2227 | bfd *tmp_bfd; | |
2228 | CORE_ADDR load_addr; | |
2229 | ||
2230 | tmp_bfd = os->objfile->obfd; | |
2231 | load_addr = ANOFFSET (os->objfile->section_offsets, | |
e03e6279 | 2232 | SECT_OFF_TEXT (os->objfile)); |
7cd25cfc DJ |
2233 | |
2234 | interp_sect = bfd_get_section_by_name (tmp_bfd, ".text"); | |
2235 | if (interp_sect) | |
2236 | { | |
6c95b8df | 2237 | info->interp_text_sect_low = |
7cd25cfc | 2238 | bfd_section_vma (tmp_bfd, interp_sect) + load_addr; |
6c95b8df PA |
2239 | info->interp_text_sect_high = |
2240 | info->interp_text_sect_low | |
2241 | + bfd_section_size (tmp_bfd, interp_sect); | |
7cd25cfc DJ |
2242 | } |
2243 | interp_sect = bfd_get_section_by_name (tmp_bfd, ".plt"); | |
2244 | if (interp_sect) | |
2245 | { | |
6c95b8df | 2246 | info->interp_plt_sect_low = |
7cd25cfc | 2247 | bfd_section_vma (tmp_bfd, interp_sect) + load_addr; |
6c95b8df PA |
2248 | info->interp_plt_sect_high = |
2249 | info->interp_plt_sect_low | |
2250 | + bfd_section_size (tmp_bfd, interp_sect); | |
7cd25cfc DJ |
2251 | } |
2252 | ||
f9e14852 | 2253 | svr4_create_solib_event_breakpoints (target_gdbarch (), sym_addr); |
7cd25cfc DJ |
2254 | return 1; |
2255 | } | |
2256 | } | |
2257 | ||
97ec2c2f | 2258 | /* Find the program interpreter; if not found, warn the user and drop |
13437d4b | 2259 | into the old breakpoint at symbol code. */ |
97ec2c2f UW |
2260 | interp_name = find_program_interpreter (); |
2261 | if (interp_name) | |
13437d4b | 2262 | { |
8ad2fcde KB |
2263 | CORE_ADDR load_addr = 0; |
2264 | int load_addr_found = 0; | |
2ec9a4f8 | 2265 | int loader_found_in_list = 0; |
f8766ec1 | 2266 | struct so_list *so; |
e4f7b8c8 | 2267 | bfd *tmp_bfd = NULL; |
2f4950cd | 2268 | struct target_ops *tmp_bfd_target; |
f1838a98 | 2269 | volatile struct gdb_exception ex; |
13437d4b | 2270 | |
7cd25cfc | 2271 | sym_addr = 0; |
13437d4b KB |
2272 | |
2273 | /* Now we need to figure out where the dynamic linker was | |
2274 | loaded so that we can load its symbols and place a breakpoint | |
2275 | in the dynamic linker itself. | |
2276 | ||
2277 | This address is stored on the stack. However, I've been unable | |
2278 | to find any magic formula to find it for Solaris (appears to | |
2279 | be trivial on GNU/Linux). Therefore, we have to try an alternate | |
2280 | mechanism to find the dynamic linker's base address. */ | |
e4f7b8c8 | 2281 | |
f1838a98 UW |
2282 | TRY_CATCH (ex, RETURN_MASK_ALL) |
2283 | { | |
97ec2c2f | 2284 | tmp_bfd = solib_bfd_open (interp_name); |
f1838a98 | 2285 | } |
13437d4b KB |
2286 | if (tmp_bfd == NULL) |
2287 | goto bkpt_at_symbol; | |
2288 | ||
2f4950cd | 2289 | /* Now convert the TMP_BFD into a target. That way target, as |
695c3173 | 2290 | well as BFD operations can be used. */ |
2f4950cd | 2291 | tmp_bfd_target = target_bfd_reopen (tmp_bfd); |
695c3173 TT |
2292 | /* target_bfd_reopen acquired its own reference, so we can |
2293 | release ours now. */ | |
2294 | gdb_bfd_unref (tmp_bfd); | |
2f4950cd | 2295 | |
f8766ec1 KB |
2296 | /* On a running target, we can get the dynamic linker's base |
2297 | address from the shared library table. */ | |
f8766ec1 KB |
2298 | so = master_so_list (); |
2299 | while (so) | |
8ad2fcde | 2300 | { |
97ec2c2f | 2301 | if (svr4_same_1 (interp_name, so->so_original_name)) |
8ad2fcde KB |
2302 | { |
2303 | load_addr_found = 1; | |
2ec9a4f8 | 2304 | loader_found_in_list = 1; |
b23518f0 | 2305 | load_addr = lm_addr_check (so, tmp_bfd); |
8ad2fcde KB |
2306 | break; |
2307 | } | |
f8766ec1 | 2308 | so = so->next; |
8ad2fcde KB |
2309 | } |
2310 | ||
8d4e36ba JB |
2311 | /* If we were not able to find the base address of the loader |
2312 | from our so_list, then try using the AT_BASE auxilliary entry. */ | |
2313 | if (!load_addr_found) | |
2314 | if (target_auxv_search (¤t_target, AT_BASE, &load_addr) > 0) | |
ad3a0e5b | 2315 | { |
f5656ead | 2316 | int addr_bit = gdbarch_addr_bit (target_gdbarch ()); |
ad3a0e5b JK |
2317 | |
2318 | /* Ensure LOAD_ADDR has proper sign in its possible upper bits so | |
2319 | that `+ load_addr' will overflow CORE_ADDR width not creating | |
2320 | invalid addresses like 0x101234567 for 32bit inferiors on 64bit | |
2321 | GDB. */ | |
2322 | ||
d182d057 | 2323 | if (addr_bit < (sizeof (CORE_ADDR) * HOST_CHAR_BIT)) |
ad3a0e5b | 2324 | { |
d182d057 | 2325 | CORE_ADDR space_size = (CORE_ADDR) 1 << addr_bit; |
ad3a0e5b JK |
2326 | CORE_ADDR tmp_entry_point = exec_entry_point (tmp_bfd, |
2327 | tmp_bfd_target); | |
2328 | ||
2329 | gdb_assert (load_addr < space_size); | |
2330 | ||
2331 | /* TMP_ENTRY_POINT exceeding SPACE_SIZE would be for prelinked | |
2332 | 64bit ld.so with 32bit executable, it should not happen. */ | |
2333 | ||
2334 | if (tmp_entry_point < space_size | |
2335 | && tmp_entry_point + load_addr >= space_size) | |
2336 | load_addr -= space_size; | |
2337 | } | |
2338 | ||
2339 | load_addr_found = 1; | |
2340 | } | |
8d4e36ba | 2341 | |
8ad2fcde KB |
2342 | /* Otherwise we find the dynamic linker's base address by examining |
2343 | the current pc (which should point at the entry point for the | |
8d4e36ba JB |
2344 | dynamic linker) and subtracting the offset of the entry point. |
2345 | ||
2346 | This is more fragile than the previous approaches, but is a good | |
2347 | fallback method because it has actually been working well in | |
2348 | most cases. */ | |
8ad2fcde | 2349 | if (!load_addr_found) |
fb14de7b | 2350 | { |
c2250ad1 | 2351 | struct regcache *regcache |
f5656ead | 2352 | = get_thread_arch_regcache (inferior_ptid, target_gdbarch ()); |
433759f7 | 2353 | |
fb14de7b UW |
2354 | load_addr = (regcache_read_pc (regcache) |
2355 | - exec_entry_point (tmp_bfd, tmp_bfd_target)); | |
2356 | } | |
2ec9a4f8 DJ |
2357 | |
2358 | if (!loader_found_in_list) | |
34439770 | 2359 | { |
1a816a87 PA |
2360 | info->debug_loader_name = xstrdup (interp_name); |
2361 | info->debug_loader_offset_p = 1; | |
2362 | info->debug_loader_offset = load_addr; | |
268a4a75 | 2363 | solib_add (NULL, from_tty, ¤t_target, auto_solib_add); |
34439770 | 2364 | } |
13437d4b KB |
2365 | |
2366 | /* Record the relocated start and end address of the dynamic linker | |
d7fa2ae2 | 2367 | text and plt section for svr4_in_dynsym_resolve_code. */ |
13437d4b KB |
2368 | interp_sect = bfd_get_section_by_name (tmp_bfd, ".text"); |
2369 | if (interp_sect) | |
2370 | { | |
6c95b8df | 2371 | info->interp_text_sect_low = |
13437d4b | 2372 | bfd_section_vma (tmp_bfd, interp_sect) + load_addr; |
6c95b8df PA |
2373 | info->interp_text_sect_high = |
2374 | info->interp_text_sect_low | |
2375 | + bfd_section_size (tmp_bfd, interp_sect); | |
13437d4b KB |
2376 | } |
2377 | interp_sect = bfd_get_section_by_name (tmp_bfd, ".plt"); | |
2378 | if (interp_sect) | |
2379 | { | |
6c95b8df | 2380 | info->interp_plt_sect_low = |
13437d4b | 2381 | bfd_section_vma (tmp_bfd, interp_sect) + load_addr; |
6c95b8df PA |
2382 | info->interp_plt_sect_high = |
2383 | info->interp_plt_sect_low | |
2384 | + bfd_section_size (tmp_bfd, interp_sect); | |
13437d4b KB |
2385 | } |
2386 | ||
2387 | /* Now try to set a breakpoint in the dynamic linker. */ | |
2388 | for (bkpt_namep = solib_break_names; *bkpt_namep != NULL; bkpt_namep++) | |
2389 | { | |
cb457ae2 YQ |
2390 | sym_addr = gdb_bfd_lookup_symbol (tmp_bfd, cmp_name_and_sec_flags, |
2391 | (void *) *bkpt_namep); | |
13437d4b KB |
2392 | if (sym_addr != 0) |
2393 | break; | |
2394 | } | |
2395 | ||
2bbe3cc1 DJ |
2396 | if (sym_addr != 0) |
2397 | /* Convert 'sym_addr' from a function pointer to an address. | |
2398 | Because we pass tmp_bfd_target instead of the current | |
2399 | target, this will always produce an unrelocated value. */ | |
f5656ead | 2400 | sym_addr = gdbarch_convert_from_func_ptr_addr (target_gdbarch (), |
2bbe3cc1 DJ |
2401 | sym_addr, |
2402 | tmp_bfd_target); | |
2403 | ||
695c3173 TT |
2404 | /* We're done with both the temporary bfd and target. Closing |
2405 | the target closes the underlying bfd, because it holds the | |
2406 | only remaining reference. */ | |
460014f5 | 2407 | target_close (tmp_bfd_target); |
13437d4b KB |
2408 | |
2409 | if (sym_addr != 0) | |
2410 | { | |
f9e14852 GB |
2411 | svr4_create_solib_event_breakpoints (target_gdbarch (), |
2412 | load_addr + sym_addr); | |
97ec2c2f | 2413 | xfree (interp_name); |
13437d4b KB |
2414 | return 1; |
2415 | } | |
2416 | ||
2417 | /* For whatever reason we couldn't set a breakpoint in the dynamic | |
2418 | linker. Warn and drop into the old code. */ | |
2419 | bkpt_at_symbol: | |
97ec2c2f | 2420 | xfree (interp_name); |
82d03102 PG |
2421 | warning (_("Unable to find dynamic linker breakpoint function.\n" |
2422 | "GDB will be unable to debug shared library initializers\n" | |
2423 | "and track explicitly loaded dynamic code.")); | |
13437d4b | 2424 | } |
13437d4b | 2425 | |
e499d0f1 DJ |
2426 | /* Scan through the lists of symbols, trying to look up the symbol and |
2427 | set a breakpoint there. Terminate loop when we/if we succeed. */ | |
2428 | ||
2429 | for (bkpt_namep = solib_break_names; *bkpt_namep != NULL; bkpt_namep++) | |
2430 | { | |
2431 | msymbol = lookup_minimal_symbol (*bkpt_namep, NULL, symfile_objfile); | |
3b7344d5 | 2432 | if ((msymbol.minsym != NULL) |
77e371c0 | 2433 | && (BMSYMBOL_VALUE_ADDRESS (msymbol) != 0)) |
e499d0f1 | 2434 | { |
77e371c0 | 2435 | sym_addr = BMSYMBOL_VALUE_ADDRESS (msymbol); |
f5656ead | 2436 | sym_addr = gdbarch_convert_from_func_ptr_addr (target_gdbarch (), |
de64a9ac JM |
2437 | sym_addr, |
2438 | ¤t_target); | |
f9e14852 | 2439 | svr4_create_solib_event_breakpoints (target_gdbarch (), sym_addr); |
e499d0f1 DJ |
2440 | return 1; |
2441 | } | |
2442 | } | |
13437d4b | 2443 | |
fb139f32 | 2444 | if (interp_name != NULL && !current_inferior ()->attach_flag) |
13437d4b | 2445 | { |
c6490bf2 | 2446 | for (bkpt_namep = bkpt_names; *bkpt_namep != NULL; bkpt_namep++) |
13437d4b | 2447 | { |
c6490bf2 | 2448 | msymbol = lookup_minimal_symbol (*bkpt_namep, NULL, symfile_objfile); |
3b7344d5 | 2449 | if ((msymbol.minsym != NULL) |
77e371c0 | 2450 | && (BMSYMBOL_VALUE_ADDRESS (msymbol) != 0)) |
c6490bf2 | 2451 | { |
77e371c0 | 2452 | sym_addr = BMSYMBOL_VALUE_ADDRESS (msymbol); |
f5656ead | 2453 | sym_addr = gdbarch_convert_from_func_ptr_addr (target_gdbarch (), |
c6490bf2 KB |
2454 | sym_addr, |
2455 | ¤t_target); | |
f9e14852 | 2456 | svr4_create_solib_event_breakpoints (target_gdbarch (), sym_addr); |
c6490bf2 KB |
2457 | return 1; |
2458 | } | |
13437d4b KB |
2459 | } |
2460 | } | |
542c95c2 | 2461 | return 0; |
13437d4b KB |
2462 | } |
2463 | ||
7f86f058 | 2464 | /* Implement the "special_symbol_handling" target_so_ops method. */ |
13437d4b KB |
2465 | |
2466 | static void | |
2467 | svr4_special_symbol_handling (void) | |
2468 | { | |
7f86f058 | 2469 | /* Nothing to do. */ |
13437d4b KB |
2470 | } |
2471 | ||
09919ac2 JK |
2472 | /* Read the ELF program headers from ABFD. Return the contents and |
2473 | set *PHDRS_SIZE to the size of the program headers. */ | |
e2a44558 | 2474 | |
09919ac2 JK |
2475 | static gdb_byte * |
2476 | read_program_headers_from_bfd (bfd *abfd, int *phdrs_size) | |
e2a44558 | 2477 | { |
09919ac2 JK |
2478 | Elf_Internal_Ehdr *ehdr; |
2479 | gdb_byte *buf; | |
e2a44558 | 2480 | |
09919ac2 | 2481 | ehdr = elf_elfheader (abfd); |
b8040f19 | 2482 | |
09919ac2 JK |
2483 | *phdrs_size = ehdr->e_phnum * ehdr->e_phentsize; |
2484 | if (*phdrs_size == 0) | |
2485 | return NULL; | |
2486 | ||
2487 | buf = xmalloc (*phdrs_size); | |
2488 | if (bfd_seek (abfd, ehdr->e_phoff, SEEK_SET) != 0 | |
2489 | || bfd_bread (buf, *phdrs_size, abfd) != *phdrs_size) | |
2490 | { | |
2491 | xfree (buf); | |
2492 | return NULL; | |
2493 | } | |
2494 | ||
2495 | return buf; | |
b8040f19 JK |
2496 | } |
2497 | ||
01c30d6e JK |
2498 | /* Return 1 and fill *DISPLACEMENTP with detected PIE offset of inferior |
2499 | exec_bfd. Otherwise return 0. | |
2500 | ||
2501 | We relocate all of the sections by the same amount. This | |
c378eb4e | 2502 | behavior is mandated by recent editions of the System V ABI. |
b8040f19 JK |
2503 | According to the System V Application Binary Interface, |
2504 | Edition 4.1, page 5-5: | |
2505 | ||
2506 | ... Though the system chooses virtual addresses for | |
2507 | individual processes, it maintains the segments' relative | |
2508 | positions. Because position-independent code uses relative | |
2509 | addressesing between segments, the difference between | |
2510 | virtual addresses in memory must match the difference | |
2511 | between virtual addresses in the file. The difference | |
2512 | between the virtual address of any segment in memory and | |
2513 | the corresponding virtual address in the file is thus a | |
2514 | single constant value for any one executable or shared | |
2515 | object in a given process. This difference is the base | |
2516 | address. One use of the base address is to relocate the | |
2517 | memory image of the program during dynamic linking. | |
2518 | ||
2519 | The same language also appears in Edition 4.0 of the System V | |
09919ac2 JK |
2520 | ABI and is left unspecified in some of the earlier editions. |
2521 | ||
2522 | Decide if the objfile needs to be relocated. As indicated above, we will | |
2523 | only be here when execution is stopped. But during attachment PC can be at | |
2524 | arbitrary address therefore regcache_read_pc can be misleading (contrary to | |
2525 | the auxv AT_ENTRY value). Moreover for executable with interpreter section | |
2526 | regcache_read_pc would point to the interpreter and not the main executable. | |
2527 | ||
2528 | So, to summarize, relocations are necessary when the start address obtained | |
2529 | from the executable is different from the address in auxv AT_ENTRY entry. | |
d989b283 | 2530 | |
09919ac2 JK |
2531 | [ The astute reader will note that we also test to make sure that |
2532 | the executable in question has the DYNAMIC flag set. It is my | |
2533 | opinion that this test is unnecessary (undesirable even). It | |
2534 | was added to avoid inadvertent relocation of an executable | |
2535 | whose e_type member in the ELF header is not ET_DYN. There may | |
2536 | be a time in the future when it is desirable to do relocations | |
2537 | on other types of files as well in which case this condition | |
2538 | should either be removed or modified to accomodate the new file | |
2539 | type. - Kevin, Nov 2000. ] */ | |
b8040f19 | 2540 | |
01c30d6e JK |
2541 | static int |
2542 | svr4_exec_displacement (CORE_ADDR *displacementp) | |
b8040f19 | 2543 | { |
41752192 JK |
2544 | /* ENTRY_POINT is a possible function descriptor - before |
2545 | a call to gdbarch_convert_from_func_ptr_addr. */ | |
09919ac2 | 2546 | CORE_ADDR entry_point, displacement; |
b8040f19 JK |
2547 | |
2548 | if (exec_bfd == NULL) | |
2549 | return 0; | |
2550 | ||
09919ac2 JK |
2551 | /* Therefore for ELF it is ET_EXEC and not ET_DYN. Both shared libraries |
2552 | being executed themselves and PIE (Position Independent Executable) | |
2553 | executables are ET_DYN. */ | |
2554 | ||
2555 | if ((bfd_get_file_flags (exec_bfd) & DYNAMIC) == 0) | |
2556 | return 0; | |
2557 | ||
2558 | if (target_auxv_search (¤t_target, AT_ENTRY, &entry_point) <= 0) | |
2559 | return 0; | |
2560 | ||
2561 | displacement = entry_point - bfd_get_start_address (exec_bfd); | |
2562 | ||
2563 | /* Verify the DISPLACEMENT candidate complies with the required page | |
2564 | alignment. It is cheaper than the program headers comparison below. */ | |
2565 | ||
2566 | if (bfd_get_flavour (exec_bfd) == bfd_target_elf_flavour) | |
2567 | { | |
2568 | const struct elf_backend_data *elf = get_elf_backend_data (exec_bfd); | |
2569 | ||
2570 | /* p_align of PT_LOAD segments does not specify any alignment but | |
2571 | only congruency of addresses: | |
2572 | p_offset % p_align == p_vaddr % p_align | |
2573 | Kernel is free to load the executable with lower alignment. */ | |
2574 | ||
2575 | if ((displacement & (elf->minpagesize - 1)) != 0) | |
2576 | return 0; | |
2577 | } | |
2578 | ||
2579 | /* Verify that the auxilliary vector describes the same file as exec_bfd, by | |
2580 | comparing their program headers. If the program headers in the auxilliary | |
2581 | vector do not match the program headers in the executable, then we are | |
2582 | looking at a different file than the one used by the kernel - for | |
2583 | instance, "gdb program" connected to "gdbserver :PORT ld.so program". */ | |
2584 | ||
2585 | if (bfd_get_flavour (exec_bfd) == bfd_target_elf_flavour) | |
2586 | { | |
2587 | /* Be optimistic and clear OK only if GDB was able to verify the headers | |
2588 | really do not match. */ | |
2589 | int phdrs_size, phdrs2_size, ok = 1; | |
2590 | gdb_byte *buf, *buf2; | |
0a1e94c7 | 2591 | int arch_size; |
09919ac2 | 2592 | |
0a1e94c7 | 2593 | buf = read_program_header (-1, &phdrs_size, &arch_size); |
09919ac2 | 2594 | buf2 = read_program_headers_from_bfd (exec_bfd, &phdrs2_size); |
0a1e94c7 JK |
2595 | if (buf != NULL && buf2 != NULL) |
2596 | { | |
f5656ead | 2597 | enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch ()); |
0a1e94c7 JK |
2598 | |
2599 | /* We are dealing with three different addresses. EXEC_BFD | |
2600 | represents current address in on-disk file. target memory content | |
2601 | may be different from EXEC_BFD as the file may have been prelinked | |
2602 | to a different address after the executable has been loaded. | |
2603 | Moreover the address of placement in target memory can be | |
3e43a32a MS |
2604 | different from what the program headers in target memory say - |
2605 | this is the goal of PIE. | |
0a1e94c7 JK |
2606 | |
2607 | Detected DISPLACEMENT covers both the offsets of PIE placement and | |
2608 | possible new prelink performed after start of the program. Here | |
2609 | relocate BUF and BUF2 just by the EXEC_BFD vs. target memory | |
2610 | content offset for the verification purpose. */ | |
2611 | ||
2612 | if (phdrs_size != phdrs2_size | |
2613 | || bfd_get_arch_size (exec_bfd) != arch_size) | |
2614 | ok = 0; | |
3e43a32a MS |
2615 | else if (arch_size == 32 |
2616 | && phdrs_size >= sizeof (Elf32_External_Phdr) | |
0a1e94c7 JK |
2617 | && phdrs_size % sizeof (Elf32_External_Phdr) == 0) |
2618 | { | |
2619 | Elf_Internal_Ehdr *ehdr2 = elf_tdata (exec_bfd)->elf_header; | |
2620 | Elf_Internal_Phdr *phdr2 = elf_tdata (exec_bfd)->phdr; | |
2621 | CORE_ADDR displacement = 0; | |
2622 | int i; | |
2623 | ||
2624 | /* DISPLACEMENT could be found more easily by the difference of | |
2625 | ehdr2->e_entry. But we haven't read the ehdr yet, and we | |
2626 | already have enough information to compute that displacement | |
2627 | with what we've read. */ | |
2628 | ||
2629 | for (i = 0; i < ehdr2->e_phnum; i++) | |
2630 | if (phdr2[i].p_type == PT_LOAD) | |
2631 | { | |
2632 | Elf32_External_Phdr *phdrp; | |
2633 | gdb_byte *buf_vaddr_p, *buf_paddr_p; | |
2634 | CORE_ADDR vaddr, paddr; | |
2635 | CORE_ADDR displacement_vaddr = 0; | |
2636 | CORE_ADDR displacement_paddr = 0; | |
2637 | ||
2638 | phdrp = &((Elf32_External_Phdr *) buf)[i]; | |
2639 | buf_vaddr_p = (gdb_byte *) &phdrp->p_vaddr; | |
2640 | buf_paddr_p = (gdb_byte *) &phdrp->p_paddr; | |
2641 | ||
2642 | vaddr = extract_unsigned_integer (buf_vaddr_p, 4, | |
2643 | byte_order); | |
2644 | displacement_vaddr = vaddr - phdr2[i].p_vaddr; | |
2645 | ||
2646 | paddr = extract_unsigned_integer (buf_paddr_p, 4, | |
2647 | byte_order); | |
2648 | displacement_paddr = paddr - phdr2[i].p_paddr; | |
2649 | ||
2650 | if (displacement_vaddr == displacement_paddr) | |
2651 | displacement = displacement_vaddr; | |
2652 | ||
2653 | break; | |
2654 | } | |
2655 | ||
2656 | /* Now compare BUF and BUF2 with optional DISPLACEMENT. */ | |
2657 | ||
2658 | for (i = 0; i < phdrs_size / sizeof (Elf32_External_Phdr); i++) | |
2659 | { | |
2660 | Elf32_External_Phdr *phdrp; | |
2661 | Elf32_External_Phdr *phdr2p; | |
2662 | gdb_byte *buf_vaddr_p, *buf_paddr_p; | |
2663 | CORE_ADDR vaddr, paddr; | |
43b8e241 | 2664 | asection *plt2_asect; |
0a1e94c7 JK |
2665 | |
2666 | phdrp = &((Elf32_External_Phdr *) buf)[i]; | |
2667 | buf_vaddr_p = (gdb_byte *) &phdrp->p_vaddr; | |
2668 | buf_paddr_p = (gdb_byte *) &phdrp->p_paddr; | |
2669 | phdr2p = &((Elf32_External_Phdr *) buf2)[i]; | |
2670 | ||
2671 | /* PT_GNU_STACK is an exception by being never relocated by | |
2672 | prelink as its addresses are always zero. */ | |
2673 | ||
2674 | if (memcmp (phdrp, phdr2p, sizeof (*phdrp)) == 0) | |
2675 | continue; | |
2676 | ||
2677 | /* Check also other adjustment combinations - PR 11786. */ | |
2678 | ||
3e43a32a MS |
2679 | vaddr = extract_unsigned_integer (buf_vaddr_p, 4, |
2680 | byte_order); | |
0a1e94c7 JK |
2681 | vaddr -= displacement; |
2682 | store_unsigned_integer (buf_vaddr_p, 4, byte_order, vaddr); | |
2683 | ||
3e43a32a MS |
2684 | paddr = extract_unsigned_integer (buf_paddr_p, 4, |
2685 | byte_order); | |
0a1e94c7 JK |
2686 | paddr -= displacement; |
2687 | store_unsigned_integer (buf_paddr_p, 4, byte_order, paddr); | |
2688 | ||
2689 | if (memcmp (phdrp, phdr2p, sizeof (*phdrp)) == 0) | |
2690 | continue; | |
2691 | ||
204b5331 DE |
2692 | /* Strip modifies the flags and alignment of PT_GNU_RELRO. |
2693 | CentOS-5 has problems with filesz, memsz as well. | |
2694 | See PR 11786. */ | |
2695 | if (phdr2[i].p_type == PT_GNU_RELRO) | |
2696 | { | |
2697 | Elf32_External_Phdr tmp_phdr = *phdrp; | |
2698 | Elf32_External_Phdr tmp_phdr2 = *phdr2p; | |
2699 | ||
2700 | memset (tmp_phdr.p_filesz, 0, 4); | |
2701 | memset (tmp_phdr.p_memsz, 0, 4); | |
2702 | memset (tmp_phdr.p_flags, 0, 4); | |
2703 | memset (tmp_phdr.p_align, 0, 4); | |
2704 | memset (tmp_phdr2.p_filesz, 0, 4); | |
2705 | memset (tmp_phdr2.p_memsz, 0, 4); | |
2706 | memset (tmp_phdr2.p_flags, 0, 4); | |
2707 | memset (tmp_phdr2.p_align, 0, 4); | |
2708 | ||
2709 | if (memcmp (&tmp_phdr, &tmp_phdr2, sizeof (tmp_phdr)) | |
2710 | == 0) | |
2711 | continue; | |
2712 | } | |
2713 | ||
43b8e241 JK |
2714 | /* prelink can convert .plt SHT_NOBITS to SHT_PROGBITS. */ |
2715 | plt2_asect = bfd_get_section_by_name (exec_bfd, ".plt"); | |
2716 | if (plt2_asect) | |
2717 | { | |
2718 | int content2; | |
2719 | gdb_byte *buf_filesz_p = (gdb_byte *) &phdrp->p_filesz; | |
2720 | CORE_ADDR filesz; | |
2721 | ||
2722 | content2 = (bfd_get_section_flags (exec_bfd, plt2_asect) | |
2723 | & SEC_HAS_CONTENTS) != 0; | |
2724 | ||
2725 | filesz = extract_unsigned_integer (buf_filesz_p, 4, | |
2726 | byte_order); | |
2727 | ||
2728 | /* PLT2_ASECT is from on-disk file (exec_bfd) while | |
2729 | FILESZ is from the in-memory image. */ | |
2730 | if (content2) | |
2731 | filesz += bfd_get_section_size (plt2_asect); | |
2732 | else | |
2733 | filesz -= bfd_get_section_size (plt2_asect); | |
2734 | ||
2735 | store_unsigned_integer (buf_filesz_p, 4, byte_order, | |
2736 | filesz); | |
2737 | ||
2738 | if (memcmp (phdrp, phdr2p, sizeof (*phdrp)) == 0) | |
2739 | continue; | |
2740 | } | |
2741 | ||
0a1e94c7 JK |
2742 | ok = 0; |
2743 | break; | |
2744 | } | |
2745 | } | |
3e43a32a MS |
2746 | else if (arch_size == 64 |
2747 | && phdrs_size >= sizeof (Elf64_External_Phdr) | |
0a1e94c7 JK |
2748 | && phdrs_size % sizeof (Elf64_External_Phdr) == 0) |
2749 | { | |
2750 | Elf_Internal_Ehdr *ehdr2 = elf_tdata (exec_bfd)->elf_header; | |
2751 | Elf_Internal_Phdr *phdr2 = elf_tdata (exec_bfd)->phdr; | |
2752 | CORE_ADDR displacement = 0; | |
2753 | int i; | |
2754 | ||
2755 | /* DISPLACEMENT could be found more easily by the difference of | |
2756 | ehdr2->e_entry. But we haven't read the ehdr yet, and we | |
2757 | already have enough information to compute that displacement | |
2758 | with what we've read. */ | |
2759 | ||
2760 | for (i = 0; i < ehdr2->e_phnum; i++) | |
2761 | if (phdr2[i].p_type == PT_LOAD) | |
2762 | { | |
2763 | Elf64_External_Phdr *phdrp; | |
2764 | gdb_byte *buf_vaddr_p, *buf_paddr_p; | |
2765 | CORE_ADDR vaddr, paddr; | |
2766 | CORE_ADDR displacement_vaddr = 0; | |
2767 | CORE_ADDR displacement_paddr = 0; | |
2768 | ||
2769 | phdrp = &((Elf64_External_Phdr *) buf)[i]; | |
2770 | buf_vaddr_p = (gdb_byte *) &phdrp->p_vaddr; | |
2771 | buf_paddr_p = (gdb_byte *) &phdrp->p_paddr; | |
2772 | ||
2773 | vaddr = extract_unsigned_integer (buf_vaddr_p, 8, | |
2774 | byte_order); | |
2775 | displacement_vaddr = vaddr - phdr2[i].p_vaddr; | |
2776 | ||
2777 | paddr = extract_unsigned_integer (buf_paddr_p, 8, | |
2778 | byte_order); | |
2779 | displacement_paddr = paddr - phdr2[i].p_paddr; | |
2780 | ||
2781 | if (displacement_vaddr == displacement_paddr) | |
2782 | displacement = displacement_vaddr; | |
2783 | ||
2784 | break; | |
2785 | } | |
2786 | ||
2787 | /* Now compare BUF and BUF2 with optional DISPLACEMENT. */ | |
2788 | ||
2789 | for (i = 0; i < phdrs_size / sizeof (Elf64_External_Phdr); i++) | |
2790 | { | |
2791 | Elf64_External_Phdr *phdrp; | |
2792 | Elf64_External_Phdr *phdr2p; | |
2793 | gdb_byte *buf_vaddr_p, *buf_paddr_p; | |
2794 | CORE_ADDR vaddr, paddr; | |
43b8e241 | 2795 | asection *plt2_asect; |
0a1e94c7 JK |
2796 | |
2797 | phdrp = &((Elf64_External_Phdr *) buf)[i]; | |
2798 | buf_vaddr_p = (gdb_byte *) &phdrp->p_vaddr; | |
2799 | buf_paddr_p = (gdb_byte *) &phdrp->p_paddr; | |
2800 | phdr2p = &((Elf64_External_Phdr *) buf2)[i]; | |
2801 | ||
2802 | /* PT_GNU_STACK is an exception by being never relocated by | |
2803 | prelink as its addresses are always zero. */ | |
2804 | ||
2805 | if (memcmp (phdrp, phdr2p, sizeof (*phdrp)) == 0) | |
2806 | continue; | |
2807 | ||
2808 | /* Check also other adjustment combinations - PR 11786. */ | |
2809 | ||
3e43a32a MS |
2810 | vaddr = extract_unsigned_integer (buf_vaddr_p, 8, |
2811 | byte_order); | |
0a1e94c7 JK |
2812 | vaddr -= displacement; |
2813 | store_unsigned_integer (buf_vaddr_p, 8, byte_order, vaddr); | |
2814 | ||
3e43a32a MS |
2815 | paddr = extract_unsigned_integer (buf_paddr_p, 8, |
2816 | byte_order); | |
0a1e94c7 JK |
2817 | paddr -= displacement; |
2818 | store_unsigned_integer (buf_paddr_p, 8, byte_order, paddr); | |
2819 | ||
2820 | if (memcmp (phdrp, phdr2p, sizeof (*phdrp)) == 0) | |
2821 | continue; | |
2822 | ||
204b5331 DE |
2823 | /* Strip modifies the flags and alignment of PT_GNU_RELRO. |
2824 | CentOS-5 has problems with filesz, memsz as well. | |
2825 | See PR 11786. */ | |
2826 | if (phdr2[i].p_type == PT_GNU_RELRO) | |
2827 | { | |
2828 | Elf64_External_Phdr tmp_phdr = *phdrp; | |
2829 | Elf64_External_Phdr tmp_phdr2 = *phdr2p; | |
2830 | ||
2831 | memset (tmp_phdr.p_filesz, 0, 8); | |
2832 | memset (tmp_phdr.p_memsz, 0, 8); | |
2833 | memset (tmp_phdr.p_flags, 0, 4); | |
2834 | memset (tmp_phdr.p_align, 0, 8); | |
2835 | memset (tmp_phdr2.p_filesz, 0, 8); | |
2836 | memset (tmp_phdr2.p_memsz, 0, 8); | |
2837 | memset (tmp_phdr2.p_flags, 0, 4); | |
2838 | memset (tmp_phdr2.p_align, 0, 8); | |
2839 | ||
2840 | if (memcmp (&tmp_phdr, &tmp_phdr2, sizeof (tmp_phdr)) | |
2841 | == 0) | |
2842 | continue; | |
2843 | } | |
2844 | ||
43b8e241 JK |
2845 | /* prelink can convert .plt SHT_NOBITS to SHT_PROGBITS. */ |
2846 | plt2_asect = bfd_get_section_by_name (exec_bfd, ".plt"); | |
2847 | if (plt2_asect) | |
2848 | { | |
2849 | int content2; | |
2850 | gdb_byte *buf_filesz_p = (gdb_byte *) &phdrp->p_filesz; | |
2851 | CORE_ADDR filesz; | |
2852 | ||
2853 | content2 = (bfd_get_section_flags (exec_bfd, plt2_asect) | |
2854 | & SEC_HAS_CONTENTS) != 0; | |
2855 | ||
2856 | filesz = extract_unsigned_integer (buf_filesz_p, 8, | |
2857 | byte_order); | |
2858 | ||
2859 | /* PLT2_ASECT is from on-disk file (exec_bfd) while | |
2860 | FILESZ is from the in-memory image. */ | |
2861 | if (content2) | |
2862 | filesz += bfd_get_section_size (plt2_asect); | |
2863 | else | |
2864 | filesz -= bfd_get_section_size (plt2_asect); | |
2865 | ||
2866 | store_unsigned_integer (buf_filesz_p, 8, byte_order, | |
2867 | filesz); | |
2868 | ||
2869 | if (memcmp (phdrp, phdr2p, sizeof (*phdrp)) == 0) | |
2870 | continue; | |
2871 | } | |
2872 | ||
0a1e94c7 JK |
2873 | ok = 0; |
2874 | break; | |
2875 | } | |
2876 | } | |
2877 | else | |
2878 | ok = 0; | |
2879 | } | |
09919ac2 JK |
2880 | |
2881 | xfree (buf); | |
2882 | xfree (buf2); | |
2883 | ||
2884 | if (!ok) | |
2885 | return 0; | |
2886 | } | |
b8040f19 | 2887 | |
ccf26247 JK |
2888 | if (info_verbose) |
2889 | { | |
2890 | /* It can be printed repeatedly as there is no easy way to check | |
2891 | the executable symbols/file has been already relocated to | |
2892 | displacement. */ | |
2893 | ||
2894 | printf_unfiltered (_("Using PIE (Position Independent Executable) " | |
2895 | "displacement %s for \"%s\".\n"), | |
f5656ead | 2896 | paddress (target_gdbarch (), displacement), |
ccf26247 JK |
2897 | bfd_get_filename (exec_bfd)); |
2898 | } | |
2899 | ||
01c30d6e JK |
2900 | *displacementp = displacement; |
2901 | return 1; | |
b8040f19 JK |
2902 | } |
2903 | ||
2904 | /* Relocate the main executable. This function should be called upon | |
c378eb4e | 2905 | stopping the inferior process at the entry point to the program. |
b8040f19 JK |
2906 | The entry point from BFD is compared to the AT_ENTRY of AUXV and if they are |
2907 | different, the main executable is relocated by the proper amount. */ | |
2908 | ||
2909 | static void | |
2910 | svr4_relocate_main_executable (void) | |
2911 | { | |
01c30d6e JK |
2912 | CORE_ADDR displacement; |
2913 | ||
4e5799b6 JK |
2914 | /* If we are re-running this executable, SYMFILE_OBJFILE->SECTION_OFFSETS |
2915 | probably contains the offsets computed using the PIE displacement | |
2916 | from the previous run, which of course are irrelevant for this run. | |
2917 | So we need to determine the new PIE displacement and recompute the | |
2918 | section offsets accordingly, even if SYMFILE_OBJFILE->SECTION_OFFSETS | |
2919 | already contains pre-computed offsets. | |
01c30d6e | 2920 | |
4e5799b6 | 2921 | If we cannot compute the PIE displacement, either: |
01c30d6e | 2922 | |
4e5799b6 JK |
2923 | - The executable is not PIE. |
2924 | ||
2925 | - SYMFILE_OBJFILE does not match the executable started in the target. | |
2926 | This can happen for main executable symbols loaded at the host while | |
2927 | `ld.so --ld-args main-executable' is loaded in the target. | |
2928 | ||
2929 | Then we leave the section offsets untouched and use them as is for | |
2930 | this run. Either: | |
2931 | ||
2932 | - These section offsets were properly reset earlier, and thus | |
2933 | already contain the correct values. This can happen for instance | |
2934 | when reconnecting via the remote protocol to a target that supports | |
2935 | the `qOffsets' packet. | |
2936 | ||
2937 | - The section offsets were not reset earlier, and the best we can | |
c378eb4e | 2938 | hope is that the old offsets are still applicable to the new run. */ |
01c30d6e JK |
2939 | |
2940 | if (! svr4_exec_displacement (&displacement)) | |
2941 | return; | |
b8040f19 | 2942 | |
01c30d6e JK |
2943 | /* Even DISPLACEMENT 0 is a valid new difference of in-memory vs. in-file |
2944 | addresses. */ | |
b8040f19 JK |
2945 | |
2946 | if (symfile_objfile) | |
e2a44558 | 2947 | { |
e2a44558 | 2948 | struct section_offsets *new_offsets; |
b8040f19 | 2949 | int i; |
e2a44558 | 2950 | |
b8040f19 JK |
2951 | new_offsets = alloca (symfile_objfile->num_sections |
2952 | * sizeof (*new_offsets)); | |
e2a44558 | 2953 | |
b8040f19 JK |
2954 | for (i = 0; i < symfile_objfile->num_sections; i++) |
2955 | new_offsets->offsets[i] = displacement; | |
e2a44558 | 2956 | |
b8040f19 | 2957 | objfile_relocate (symfile_objfile, new_offsets); |
e2a44558 | 2958 | } |
51bee8e9 JK |
2959 | else if (exec_bfd) |
2960 | { | |
2961 | asection *asect; | |
2962 | ||
2963 | for (asect = exec_bfd->sections; asect != NULL; asect = asect->next) | |
2964 | exec_set_section_address (bfd_get_filename (exec_bfd), asect->index, | |
2965 | (bfd_section_vma (exec_bfd, asect) | |
2966 | + displacement)); | |
2967 | } | |
e2a44558 KB |
2968 | } |
2969 | ||
7f86f058 | 2970 | /* Implement the "create_inferior_hook" target_solib_ops method. |
13437d4b KB |
2971 | |
2972 | For SVR4 executables, this first instruction is either the first | |
2973 | instruction in the dynamic linker (for dynamically linked | |
2974 | executables) or the instruction at "start" for statically linked | |
2975 | executables. For dynamically linked executables, the system | |
2976 | first exec's /lib/libc.so.N, which contains the dynamic linker, | |
2977 | and starts it running. The dynamic linker maps in any needed | |
2978 | shared libraries, maps in the actual user executable, and then | |
2979 | jumps to "start" in the user executable. | |
2980 | ||
7f86f058 PA |
2981 | We can arrange to cooperate with the dynamic linker to discover the |
2982 | names of shared libraries that are dynamically linked, and the base | |
2983 | addresses to which they are linked. | |
13437d4b KB |
2984 | |
2985 | This function is responsible for discovering those names and | |
2986 | addresses, and saving sufficient information about them to allow | |
d2e5c99a | 2987 | their symbols to be read at a later time. */ |
13437d4b | 2988 | |
e2a44558 | 2989 | static void |
268a4a75 | 2990 | svr4_solib_create_inferior_hook (int from_tty) |
13437d4b | 2991 | { |
1a816a87 PA |
2992 | struct svr4_info *info; |
2993 | ||
6c95b8df | 2994 | info = get_svr4_info (); |
2020b7ab | 2995 | |
f9e14852 GB |
2996 | /* Clear the probes-based interface's state. */ |
2997 | free_probes_table (info); | |
2998 | free_solib_list (info); | |
2999 | ||
e2a44558 | 3000 | /* Relocate the main executable if necessary. */ |
86e4bafc | 3001 | svr4_relocate_main_executable (); |
e2a44558 | 3002 | |
c91c8c16 PA |
3003 | /* No point setting a breakpoint in the dynamic linker if we can't |
3004 | hit it (e.g., a core file, or a trace file). */ | |
3005 | if (!target_has_execution) | |
3006 | return; | |
3007 | ||
d5a921c9 | 3008 | if (!svr4_have_link_map_offsets ()) |
513f5903 | 3009 | return; |
d5a921c9 | 3010 | |
268a4a75 | 3011 | if (!enable_break (info, from_tty)) |
542c95c2 | 3012 | return; |
13437d4b KB |
3013 | } |
3014 | ||
3015 | static void | |
3016 | svr4_clear_solib (void) | |
3017 | { | |
6c95b8df PA |
3018 | struct svr4_info *info; |
3019 | ||
3020 | info = get_svr4_info (); | |
3021 | info->debug_base = 0; | |
3022 | info->debug_loader_offset_p = 0; | |
3023 | info->debug_loader_offset = 0; | |
3024 | xfree (info->debug_loader_name); | |
3025 | info->debug_loader_name = NULL; | |
13437d4b KB |
3026 | } |
3027 | ||
6bb7be43 JB |
3028 | /* Clear any bits of ADDR that wouldn't fit in a target-format |
3029 | data pointer. "Data pointer" here refers to whatever sort of | |
3030 | address the dynamic linker uses to manage its sections. At the | |
3031 | moment, we don't support shared libraries on any processors where | |
3032 | code and data pointers are different sizes. | |
3033 | ||
3034 | This isn't really the right solution. What we really need here is | |
3035 | a way to do arithmetic on CORE_ADDR values that respects the | |
3036 | natural pointer/address correspondence. (For example, on the MIPS, | |
3037 | converting a 32-bit pointer to a 64-bit CORE_ADDR requires you to | |
3038 | sign-extend the value. There, simply truncating the bits above | |
819844ad | 3039 | gdbarch_ptr_bit, as we do below, is no good.) This should probably |
6bb7be43 JB |
3040 | be a new gdbarch method or something. */ |
3041 | static CORE_ADDR | |
3042 | svr4_truncate_ptr (CORE_ADDR addr) | |
3043 | { | |
f5656ead | 3044 | if (gdbarch_ptr_bit (target_gdbarch ()) == sizeof (CORE_ADDR) * 8) |
6bb7be43 JB |
3045 | /* We don't need to truncate anything, and the bit twiddling below |
3046 | will fail due to overflow problems. */ | |
3047 | return addr; | |
3048 | else | |
f5656ead | 3049 | return addr & (((CORE_ADDR) 1 << gdbarch_ptr_bit (target_gdbarch ())) - 1); |
6bb7be43 JB |
3050 | } |
3051 | ||
3052 | ||
749499cb KB |
3053 | static void |
3054 | svr4_relocate_section_addresses (struct so_list *so, | |
0542c86d | 3055 | struct target_section *sec) |
749499cb | 3056 | { |
2b2848e2 DE |
3057 | bfd *abfd = sec->the_bfd_section->owner; |
3058 | ||
3059 | sec->addr = svr4_truncate_ptr (sec->addr + lm_addr_check (so, abfd)); | |
3060 | sec->endaddr = svr4_truncate_ptr (sec->endaddr + lm_addr_check (so, abfd)); | |
749499cb | 3061 | } |
4b188b9f | 3062 | \f |
749499cb | 3063 | |
4b188b9f | 3064 | /* Architecture-specific operations. */ |
6bb7be43 | 3065 | |
4b188b9f MK |
3066 | /* Per-architecture data key. */ |
3067 | static struct gdbarch_data *solib_svr4_data; | |
e5e2b9ff | 3068 | |
4b188b9f | 3069 | struct solib_svr4_ops |
e5e2b9ff | 3070 | { |
4b188b9f MK |
3071 | /* Return a description of the layout of `struct link_map'. */ |
3072 | struct link_map_offsets *(*fetch_link_map_offsets)(void); | |
3073 | }; | |
e5e2b9ff | 3074 | |
4b188b9f | 3075 | /* Return a default for the architecture-specific operations. */ |
e5e2b9ff | 3076 | |
4b188b9f MK |
3077 | static void * |
3078 | solib_svr4_init (struct obstack *obstack) | |
e5e2b9ff | 3079 | { |
4b188b9f | 3080 | struct solib_svr4_ops *ops; |
e5e2b9ff | 3081 | |
4b188b9f | 3082 | ops = OBSTACK_ZALLOC (obstack, struct solib_svr4_ops); |
8d005789 | 3083 | ops->fetch_link_map_offsets = NULL; |
4b188b9f | 3084 | return ops; |
e5e2b9ff KB |
3085 | } |
3086 | ||
4b188b9f | 3087 | /* Set the architecture-specific `struct link_map_offsets' fetcher for |
7e3cb44c | 3088 | GDBARCH to FLMO. Also, install SVR4 solib_ops into GDBARCH. */ |
1c4dcb57 | 3089 | |
21479ded | 3090 | void |
e5e2b9ff KB |
3091 | set_solib_svr4_fetch_link_map_offsets (struct gdbarch *gdbarch, |
3092 | struct link_map_offsets *(*flmo) (void)) | |
21479ded | 3093 | { |
4b188b9f MK |
3094 | struct solib_svr4_ops *ops = gdbarch_data (gdbarch, solib_svr4_data); |
3095 | ||
3096 | ops->fetch_link_map_offsets = flmo; | |
7e3cb44c UW |
3097 | |
3098 | set_solib_ops (gdbarch, &svr4_so_ops); | |
21479ded KB |
3099 | } |
3100 | ||
4b188b9f MK |
3101 | /* Fetch a link_map_offsets structure using the architecture-specific |
3102 | `struct link_map_offsets' fetcher. */ | |
1c4dcb57 | 3103 | |
4b188b9f MK |
3104 | static struct link_map_offsets * |
3105 | svr4_fetch_link_map_offsets (void) | |
21479ded | 3106 | { |
f5656ead | 3107 | struct solib_svr4_ops *ops = gdbarch_data (target_gdbarch (), solib_svr4_data); |
4b188b9f MK |
3108 | |
3109 | gdb_assert (ops->fetch_link_map_offsets); | |
3110 | return ops->fetch_link_map_offsets (); | |
21479ded KB |
3111 | } |
3112 | ||
4b188b9f MK |
3113 | /* Return 1 if a link map offset fetcher has been defined, 0 otherwise. */ |
3114 | ||
3115 | static int | |
3116 | svr4_have_link_map_offsets (void) | |
3117 | { | |
f5656ead | 3118 | struct solib_svr4_ops *ops = gdbarch_data (target_gdbarch (), solib_svr4_data); |
433759f7 | 3119 | |
4b188b9f MK |
3120 | return (ops->fetch_link_map_offsets != NULL); |
3121 | } | |
3122 | \f | |
3123 | ||
e4bbbda8 MK |
3124 | /* Most OS'es that have SVR4-style ELF dynamic libraries define a |
3125 | `struct r_debug' and a `struct link_map' that are binary compatible | |
3126 | with the origional SVR4 implementation. */ | |
3127 | ||
3128 | /* Fetch (and possibly build) an appropriate `struct link_map_offsets' | |
3129 | for an ILP32 SVR4 system. */ | |
d989b283 | 3130 | |
e4bbbda8 MK |
3131 | struct link_map_offsets * |
3132 | svr4_ilp32_fetch_link_map_offsets (void) | |
3133 | { | |
3134 | static struct link_map_offsets lmo; | |
3135 | static struct link_map_offsets *lmp = NULL; | |
3136 | ||
3137 | if (lmp == NULL) | |
3138 | { | |
3139 | lmp = &lmo; | |
3140 | ||
e4cd0d6a MK |
3141 | lmo.r_version_offset = 0; |
3142 | lmo.r_version_size = 4; | |
e4bbbda8 | 3143 | lmo.r_map_offset = 4; |
7cd25cfc | 3144 | lmo.r_brk_offset = 8; |
e4cd0d6a | 3145 | lmo.r_ldsomap_offset = 20; |
e4bbbda8 MK |
3146 | |
3147 | /* Everything we need is in the first 20 bytes. */ | |
3148 | lmo.link_map_size = 20; | |
3149 | lmo.l_addr_offset = 0; | |
e4bbbda8 | 3150 | lmo.l_name_offset = 4; |
cc10cae3 | 3151 | lmo.l_ld_offset = 8; |
e4bbbda8 | 3152 | lmo.l_next_offset = 12; |
e4bbbda8 | 3153 | lmo.l_prev_offset = 16; |
e4bbbda8 MK |
3154 | } |
3155 | ||
3156 | return lmp; | |
3157 | } | |
3158 | ||
3159 | /* Fetch (and possibly build) an appropriate `struct link_map_offsets' | |
3160 | for an LP64 SVR4 system. */ | |
d989b283 | 3161 | |
e4bbbda8 MK |
3162 | struct link_map_offsets * |
3163 | svr4_lp64_fetch_link_map_offsets (void) | |
3164 | { | |
3165 | static struct link_map_offsets lmo; | |
3166 | static struct link_map_offsets *lmp = NULL; | |
3167 | ||
3168 | if (lmp == NULL) | |
3169 | { | |
3170 | lmp = &lmo; | |
3171 | ||
e4cd0d6a MK |
3172 | lmo.r_version_offset = 0; |
3173 | lmo.r_version_size = 4; | |
e4bbbda8 | 3174 | lmo.r_map_offset = 8; |
7cd25cfc | 3175 | lmo.r_brk_offset = 16; |
e4cd0d6a | 3176 | lmo.r_ldsomap_offset = 40; |
e4bbbda8 MK |
3177 | |
3178 | /* Everything we need is in the first 40 bytes. */ | |
3179 | lmo.link_map_size = 40; | |
3180 | lmo.l_addr_offset = 0; | |
e4bbbda8 | 3181 | lmo.l_name_offset = 8; |
cc10cae3 | 3182 | lmo.l_ld_offset = 16; |
e4bbbda8 | 3183 | lmo.l_next_offset = 24; |
e4bbbda8 | 3184 | lmo.l_prev_offset = 32; |
e4bbbda8 MK |
3185 | } |
3186 | ||
3187 | return lmp; | |
3188 | } | |
3189 | \f | |
3190 | ||
7d522c90 | 3191 | struct target_so_ops svr4_so_ops; |
13437d4b | 3192 | |
c378eb4e | 3193 | /* Lookup global symbol for ELF DSOs linked with -Bsymbolic. Those DSOs have a |
3a40aaa0 UW |
3194 | different rule for symbol lookup. The lookup begins here in the DSO, not in |
3195 | the main executable. */ | |
3196 | ||
3197 | static struct symbol * | |
3198 | elf_lookup_lib_symbol (const struct objfile *objfile, | |
3199 | const char *name, | |
21b556f4 | 3200 | const domain_enum domain) |
3a40aaa0 | 3201 | { |
61f0d762 JK |
3202 | bfd *abfd; |
3203 | ||
3204 | if (objfile == symfile_objfile) | |
3205 | abfd = exec_bfd; | |
3206 | else | |
3207 | { | |
3208 | /* OBJFILE should have been passed as the non-debug one. */ | |
3209 | gdb_assert (objfile->separate_debug_objfile_backlink == NULL); | |
3210 | ||
3211 | abfd = objfile->obfd; | |
3212 | } | |
3213 | ||
3214 | if (abfd == NULL || scan_dyntag (DT_SYMBOLIC, abfd, NULL) != 1) | |
3a40aaa0 UW |
3215 | return NULL; |
3216 | ||
94af9270 | 3217 | return lookup_global_symbol_from_objfile (objfile, name, domain); |
3a40aaa0 UW |
3218 | } |
3219 | ||
a78f21af AC |
3220 | extern initialize_file_ftype _initialize_svr4_solib; /* -Wmissing-prototypes */ |
3221 | ||
13437d4b KB |
3222 | void |
3223 | _initialize_svr4_solib (void) | |
3224 | { | |
4b188b9f | 3225 | solib_svr4_data = gdbarch_data_register_pre_init (solib_svr4_init); |
6c95b8df | 3226 | solib_svr4_pspace_data |
8e260fc0 | 3227 | = register_program_space_data_with_cleanup (NULL, svr4_pspace_data_cleanup); |
4b188b9f | 3228 | |
749499cb | 3229 | svr4_so_ops.relocate_section_addresses = svr4_relocate_section_addresses; |
13437d4b | 3230 | svr4_so_ops.free_so = svr4_free_so; |
0892cb63 | 3231 | svr4_so_ops.clear_so = svr4_clear_so; |
13437d4b KB |
3232 | svr4_so_ops.clear_solib = svr4_clear_solib; |
3233 | svr4_so_ops.solib_create_inferior_hook = svr4_solib_create_inferior_hook; | |
3234 | svr4_so_ops.special_symbol_handling = svr4_special_symbol_handling; | |
3235 | svr4_so_ops.current_sos = svr4_current_sos; | |
3236 | svr4_so_ops.open_symbol_file_object = open_symbol_file_object; | |
d7fa2ae2 | 3237 | svr4_so_ops.in_dynsym_resolve_code = svr4_in_dynsym_resolve_code; |
831a0c44 | 3238 | svr4_so_ops.bfd_open = solib_bfd_open; |
3a40aaa0 | 3239 | svr4_so_ops.lookup_lib_global_symbol = elf_lookup_lib_symbol; |
a7c02bc8 | 3240 | svr4_so_ops.same = svr4_same; |
de18c1d8 | 3241 | svr4_so_ops.keep_data_in_core = svr4_keep_data_in_core; |
f9e14852 GB |
3242 | svr4_so_ops.update_breakpoints = svr4_update_solib_event_breakpoints; |
3243 | svr4_so_ops.handle_event = svr4_handle_solib_event; | |
13437d4b | 3244 | } |