Commit | Line | Data |
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ab31aa69 | 1 | /* Handle SVR4 shared libraries for GDB, the GNU Debugger. |
2f4950cd | 2 | |
6aba47ca DJ |
3 | Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, |
4 | 2001, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc. | |
13437d4b KB |
5 | |
6 | This file is part of GDB. | |
7 | ||
8 | This program is free software; you can redistribute it and/or modify | |
9 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 10 | the Free Software Foundation; either version 3 of the License, or |
13437d4b KB |
11 | (at your option) any later version. |
12 | ||
13 | This program is distributed in the hope that it will be useful, | |
14 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | GNU General Public License for more details. | |
17 | ||
18 | You should have received a copy of the GNU General Public License | |
a9762ec7 | 19 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
13437d4b | 20 | |
13437d4b KB |
21 | #include "defs.h" |
22 | ||
13437d4b | 23 | #include "elf/external.h" |
21479ded | 24 | #include "elf/common.h" |
f7856c8f | 25 | #include "elf/mips.h" |
13437d4b KB |
26 | |
27 | #include "symtab.h" | |
28 | #include "bfd.h" | |
29 | #include "symfile.h" | |
30 | #include "objfiles.h" | |
31 | #include "gdbcore.h" | |
13437d4b | 32 | #include "target.h" |
13437d4b | 33 | #include "inferior.h" |
13437d4b | 34 | |
4b188b9f MK |
35 | #include "gdb_assert.h" |
36 | ||
13437d4b | 37 | #include "solist.h" |
bba93f6c | 38 | #include "solib.h" |
13437d4b KB |
39 | #include "solib-svr4.h" |
40 | ||
2f4950cd | 41 | #include "bfd-target.h" |
cc10cae3 | 42 | #include "elf-bfd.h" |
2f4950cd AC |
43 | #include "exec.h" |
44 | ||
e5e2b9ff | 45 | static struct link_map_offsets *svr4_fetch_link_map_offsets (void); |
d5a921c9 | 46 | static int svr4_have_link_map_offsets (void); |
1c4dcb57 | 47 | |
4b188b9f MK |
48 | /* This hook is set to a function that provides native link map |
49 | offsets if the code in solib-legacy.c is linked in. */ | |
50 | struct link_map_offsets *(*legacy_svr4_fetch_link_map_offsets_hook) (void); | |
21479ded | 51 | |
13437d4b KB |
52 | /* Link map info to include in an allocated so_list entry */ |
53 | ||
54 | struct lm_info | |
55 | { | |
56 | /* Pointer to copy of link map from inferior. The type is char * | |
57 | rather than void *, so that we may use byte offsets to find the | |
58 | various fields without the need for a cast. */ | |
4066fc10 | 59 | gdb_byte *lm; |
cc10cae3 AO |
60 | |
61 | /* Amount by which addresses in the binary should be relocated to | |
62 | match the inferior. This could most often be taken directly | |
63 | from lm, but when prelinking is involved and the prelink base | |
64 | address changes, we may need a different offset, we want to | |
65 | warn about the difference and compute it only once. */ | |
66 | CORE_ADDR l_addr; | |
13437d4b KB |
67 | }; |
68 | ||
69 | /* On SVR4 systems, a list of symbols in the dynamic linker where | |
70 | GDB can try to place a breakpoint to monitor shared library | |
71 | events. | |
72 | ||
73 | If none of these symbols are found, or other errors occur, then | |
74 | SVR4 systems will fall back to using a symbol as the "startup | |
75 | mapping complete" breakpoint address. */ | |
76 | ||
13437d4b KB |
77 | static char *solib_break_names[] = |
78 | { | |
79 | "r_debug_state", | |
80 | "_r_debug_state", | |
81 | "_dl_debug_state", | |
82 | "rtld_db_dlactivity", | |
1f72e589 | 83 | "_rtld_debug_state", |
4c0122c8 | 84 | |
13437d4b KB |
85 | NULL |
86 | }; | |
13437d4b KB |
87 | |
88 | #define BKPT_AT_SYMBOL 1 | |
89 | ||
ab31aa69 | 90 | #if defined (BKPT_AT_SYMBOL) |
13437d4b KB |
91 | static char *bkpt_names[] = |
92 | { | |
93 | #ifdef SOLIB_BKPT_NAME | |
94 | SOLIB_BKPT_NAME, /* Prefer configured name if it exists. */ | |
95 | #endif | |
96 | "_start", | |
ad3dcc5c | 97 | "__start", |
13437d4b KB |
98 | "main", |
99 | NULL | |
100 | }; | |
101 | #endif | |
102 | ||
13437d4b KB |
103 | static char *main_name_list[] = |
104 | { | |
105 | "main_$main", | |
106 | NULL | |
107 | }; | |
108 | ||
13437d4b KB |
109 | /* link map access functions */ |
110 | ||
111 | static CORE_ADDR | |
cc10cae3 | 112 | LM_ADDR_FROM_LINK_MAP (struct so_list *so) |
13437d4b | 113 | { |
4b188b9f | 114 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); |
13437d4b | 115 | |
cfaefc65 AS |
116 | return extract_typed_address (so->lm_info->lm + lmo->l_addr_offset, |
117 | builtin_type_void_data_ptr); | |
13437d4b KB |
118 | } |
119 | ||
cc10cae3 AO |
120 | static int |
121 | HAS_LM_DYNAMIC_FROM_LINK_MAP () | |
122 | { | |
123 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); | |
124 | ||
cfaefc65 | 125 | return lmo->l_ld_offset >= 0; |
cc10cae3 AO |
126 | } |
127 | ||
128 | static CORE_ADDR | |
129 | LM_DYNAMIC_FROM_LINK_MAP (struct so_list *so) | |
130 | { | |
131 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); | |
132 | ||
cfaefc65 AS |
133 | return extract_typed_address (so->lm_info->lm + lmo->l_ld_offset, |
134 | builtin_type_void_data_ptr); | |
cc10cae3 AO |
135 | } |
136 | ||
137 | static CORE_ADDR | |
138 | LM_ADDR_CHECK (struct so_list *so, bfd *abfd) | |
139 | { | |
140 | if (so->lm_info->l_addr == (CORE_ADDR)-1) | |
141 | { | |
142 | struct bfd_section *dyninfo_sect; | |
143 | CORE_ADDR l_addr, l_dynaddr, dynaddr, align = 0x1000; | |
144 | ||
145 | l_addr = LM_ADDR_FROM_LINK_MAP (so); | |
146 | ||
147 | if (! abfd || ! HAS_LM_DYNAMIC_FROM_LINK_MAP ()) | |
148 | goto set_addr; | |
149 | ||
150 | l_dynaddr = LM_DYNAMIC_FROM_LINK_MAP (so); | |
151 | ||
152 | dyninfo_sect = bfd_get_section_by_name (abfd, ".dynamic"); | |
153 | if (dyninfo_sect == NULL) | |
154 | goto set_addr; | |
155 | ||
156 | dynaddr = bfd_section_vma (abfd, dyninfo_sect); | |
157 | ||
158 | if (dynaddr + l_addr != l_dynaddr) | |
159 | { | |
cc10cae3 AO |
160 | if (bfd_get_flavour (abfd) == bfd_target_elf_flavour) |
161 | { | |
162 | Elf_Internal_Ehdr *ehdr = elf_tdata (abfd)->elf_header; | |
163 | Elf_Internal_Phdr *phdr = elf_tdata (abfd)->phdr; | |
164 | int i; | |
165 | ||
166 | align = 1; | |
167 | ||
168 | for (i = 0; i < ehdr->e_phnum; i++) | |
169 | if (phdr[i].p_type == PT_LOAD && phdr[i].p_align > align) | |
170 | align = phdr[i].p_align; | |
171 | } | |
172 | ||
173 | /* Turn it into a mask. */ | |
174 | align--; | |
175 | ||
176 | /* If the changes match the alignment requirements, we | |
177 | assume we're using a core file that was generated by the | |
178 | same binary, just prelinked with a different base offset. | |
179 | If it doesn't match, we may have a different binary, the | |
180 | same binary with the dynamic table loaded at an unrelated | |
181 | location, or anything, really. To avoid regressions, | |
182 | don't adjust the base offset in the latter case, although | |
183 | odds are that, if things really changed, debugging won't | |
184 | quite work. */ | |
f1e55806 | 185 | if ((l_addr & align) == ((l_dynaddr - dynaddr) & align)) |
cc10cae3 AO |
186 | { |
187 | l_addr = l_dynaddr - dynaddr; | |
79d4c408 DJ |
188 | |
189 | warning (_(".dynamic section for \"%s\" " | |
190 | "is not at the expected address"), so->so_name); | |
cc10cae3 AO |
191 | warning (_("difference appears to be caused by prelink, " |
192 | "adjusting expectations")); | |
193 | } | |
79d4c408 DJ |
194 | else |
195 | warning (_(".dynamic section for \"%s\" " | |
196 | "is not at the expected address " | |
197 | "(wrong library or version mismatch?)"), so->so_name); | |
cc10cae3 AO |
198 | } |
199 | ||
200 | set_addr: | |
201 | so->lm_info->l_addr = l_addr; | |
202 | } | |
203 | ||
204 | return so->lm_info->l_addr; | |
205 | } | |
206 | ||
13437d4b KB |
207 | static CORE_ADDR |
208 | LM_NEXT (struct so_list *so) | |
209 | { | |
4b188b9f | 210 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); |
13437d4b | 211 | |
cfaefc65 AS |
212 | return extract_typed_address (so->lm_info->lm + lmo->l_next_offset, |
213 | builtin_type_void_data_ptr); | |
13437d4b KB |
214 | } |
215 | ||
216 | static CORE_ADDR | |
217 | LM_NAME (struct so_list *so) | |
218 | { | |
4b188b9f | 219 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); |
13437d4b | 220 | |
cfaefc65 AS |
221 | return extract_typed_address (so->lm_info->lm + lmo->l_name_offset, |
222 | builtin_type_void_data_ptr); | |
13437d4b KB |
223 | } |
224 | ||
13437d4b KB |
225 | static int |
226 | IGNORE_FIRST_LINK_MAP_ENTRY (struct so_list *so) | |
227 | { | |
4b188b9f | 228 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); |
13437d4b | 229 | |
e499d0f1 DJ |
230 | /* Assume that everything is a library if the dynamic loader was loaded |
231 | late by a static executable. */ | |
232 | if (bfd_get_section_by_name (exec_bfd, ".dynamic") == NULL) | |
233 | return 0; | |
234 | ||
cfaefc65 AS |
235 | return extract_typed_address (so->lm_info->lm + lmo->l_prev_offset, |
236 | builtin_type_void_data_ptr) == 0; | |
13437d4b KB |
237 | } |
238 | ||
13437d4b | 239 | static CORE_ADDR debug_base; /* Base of dynamic linker structures */ |
13437d4b | 240 | |
34439770 DJ |
241 | /* Validity flag for debug_loader_offset. */ |
242 | static int debug_loader_offset_p; | |
243 | ||
244 | /* Load address for the dynamic linker, inferred. */ | |
245 | static CORE_ADDR debug_loader_offset; | |
246 | ||
247 | /* Name of the dynamic linker, valid if debug_loader_offset_p. */ | |
248 | static char *debug_loader_name; | |
249 | ||
13437d4b KB |
250 | /* Local function prototypes */ |
251 | ||
252 | static int match_main (char *); | |
253 | ||
2bbe3cc1 | 254 | static CORE_ADDR bfd_lookup_symbol (bfd *, char *); |
13437d4b KB |
255 | |
256 | /* | |
257 | ||
258 | LOCAL FUNCTION | |
259 | ||
260 | bfd_lookup_symbol -- lookup the value for a specific symbol | |
261 | ||
262 | SYNOPSIS | |
263 | ||
2bbe3cc1 | 264 | CORE_ADDR bfd_lookup_symbol (bfd *abfd, char *symname) |
13437d4b KB |
265 | |
266 | DESCRIPTION | |
267 | ||
268 | An expensive way to lookup the value of a single symbol for | |
269 | bfd's that are only temporary anyway. This is used by the | |
270 | shared library support to find the address of the debugger | |
2bbe3cc1 | 271 | notification routine in the shared library. |
13437d4b | 272 | |
2bbe3cc1 DJ |
273 | The returned symbol may be in a code or data section; functions |
274 | will normally be in a code section, but may be in a data section | |
275 | if this architecture uses function descriptors. | |
87f84c9d | 276 | |
13437d4b KB |
277 | Note that 0 is specifically allowed as an error return (no |
278 | such symbol). | |
279 | */ | |
280 | ||
281 | static CORE_ADDR | |
2bbe3cc1 | 282 | bfd_lookup_symbol (bfd *abfd, char *symname) |
13437d4b | 283 | { |
435b259c | 284 | long storage_needed; |
13437d4b KB |
285 | asymbol *sym; |
286 | asymbol **symbol_table; | |
287 | unsigned int number_of_symbols; | |
288 | unsigned int i; | |
289 | struct cleanup *back_to; | |
290 | CORE_ADDR symaddr = 0; | |
291 | ||
292 | storage_needed = bfd_get_symtab_upper_bound (abfd); | |
293 | ||
294 | if (storage_needed > 0) | |
295 | { | |
296 | symbol_table = (asymbol **) xmalloc (storage_needed); | |
4efb68b1 | 297 | back_to = make_cleanup (xfree, symbol_table); |
13437d4b KB |
298 | number_of_symbols = bfd_canonicalize_symtab (abfd, symbol_table); |
299 | ||
300 | for (i = 0; i < number_of_symbols; i++) | |
301 | { | |
302 | sym = *symbol_table++; | |
6314a349 | 303 | if (strcmp (sym->name, symname) == 0 |
2bbe3cc1 | 304 | && (sym->section->flags & (SEC_CODE | SEC_DATA)) != 0) |
13437d4b | 305 | { |
2bbe3cc1 | 306 | /* BFD symbols are section relative. */ |
13437d4b KB |
307 | symaddr = sym->value + sym->section->vma; |
308 | break; | |
309 | } | |
310 | } | |
311 | do_cleanups (back_to); | |
312 | } | |
313 | ||
314 | if (symaddr) | |
315 | return symaddr; | |
316 | ||
317 | /* On FreeBSD, the dynamic linker is stripped by default. So we'll | |
318 | have to check the dynamic string table too. */ | |
319 | ||
320 | storage_needed = bfd_get_dynamic_symtab_upper_bound (abfd); | |
321 | ||
322 | if (storage_needed > 0) | |
323 | { | |
324 | symbol_table = (asymbol **) xmalloc (storage_needed); | |
4efb68b1 | 325 | back_to = make_cleanup (xfree, symbol_table); |
13437d4b KB |
326 | number_of_symbols = bfd_canonicalize_dynamic_symtab (abfd, symbol_table); |
327 | ||
328 | for (i = 0; i < number_of_symbols; i++) | |
329 | { | |
330 | sym = *symbol_table++; | |
87f84c9d | 331 | |
6314a349 | 332 | if (strcmp (sym->name, symname) == 0 |
2bbe3cc1 | 333 | && (sym->section->flags & (SEC_CODE | SEC_DATA)) != 0) |
13437d4b | 334 | { |
2bbe3cc1 | 335 | /* BFD symbols are section relative. */ |
13437d4b KB |
336 | symaddr = sym->value + sym->section->vma; |
337 | break; | |
338 | } | |
339 | } | |
340 | do_cleanups (back_to); | |
341 | } | |
342 | ||
343 | return symaddr; | |
344 | } | |
345 | ||
3a40aaa0 UW |
346 | /* Scan for DYNTAG in .dynamic section of ABFD. If DYNTAG is found 1 is |
347 | returned and the corresponding PTR is set. */ | |
348 | ||
349 | static int | |
350 | scan_dyntag (int dyntag, bfd *abfd, CORE_ADDR *ptr) | |
351 | { | |
352 | int arch_size, step, sect_size; | |
353 | long dyn_tag; | |
354 | CORE_ADDR dyn_ptr, dyn_addr; | |
65728c26 | 355 | gdb_byte *bufend, *bufstart, *buf; |
3a40aaa0 UW |
356 | Elf32_External_Dyn *x_dynp_32; |
357 | Elf64_External_Dyn *x_dynp_64; | |
358 | struct bfd_section *sect; | |
359 | ||
360 | if (abfd == NULL) | |
361 | return 0; | |
362 | arch_size = bfd_get_arch_size (abfd); | |
363 | if (arch_size == -1) | |
364 | return 0; | |
365 | ||
366 | /* Find the start address of the .dynamic section. */ | |
367 | sect = bfd_get_section_by_name (abfd, ".dynamic"); | |
368 | if (sect == NULL) | |
369 | return 0; | |
370 | dyn_addr = bfd_section_vma (abfd, sect); | |
371 | ||
65728c26 DJ |
372 | /* Read in .dynamic from the BFD. We will get the actual value |
373 | from memory later. */ | |
3a40aaa0 | 374 | sect_size = bfd_section_size (abfd, sect); |
65728c26 DJ |
375 | buf = bufstart = alloca (sect_size); |
376 | if (!bfd_get_section_contents (abfd, sect, | |
377 | buf, 0, sect_size)) | |
378 | return 0; | |
3a40aaa0 UW |
379 | |
380 | /* Iterate over BUF and scan for DYNTAG. If found, set PTR and return. */ | |
381 | step = (arch_size == 32) ? sizeof (Elf32_External_Dyn) | |
382 | : sizeof (Elf64_External_Dyn); | |
383 | for (bufend = buf + sect_size; | |
384 | buf < bufend; | |
385 | buf += step) | |
386 | { | |
387 | if (arch_size == 32) | |
388 | { | |
389 | x_dynp_32 = (Elf32_External_Dyn *) buf; | |
390 | dyn_tag = bfd_h_get_32 (abfd, (bfd_byte *) x_dynp_32->d_tag); | |
391 | dyn_ptr = bfd_h_get_32 (abfd, (bfd_byte *) x_dynp_32->d_un.d_ptr); | |
392 | } | |
65728c26 | 393 | else |
3a40aaa0 UW |
394 | { |
395 | x_dynp_64 = (Elf64_External_Dyn *) buf; | |
396 | dyn_tag = bfd_h_get_64 (abfd, (bfd_byte *) x_dynp_64->d_tag); | |
397 | dyn_ptr = bfd_h_get_64 (abfd, (bfd_byte *) x_dynp_64->d_un.d_ptr); | |
398 | } | |
399 | if (dyn_tag == DT_NULL) | |
400 | return 0; | |
401 | if (dyn_tag == dyntag) | |
402 | { | |
65728c26 DJ |
403 | /* If requested, try to read the runtime value of this .dynamic |
404 | entry. */ | |
3a40aaa0 | 405 | if (ptr) |
65728c26 DJ |
406 | { |
407 | gdb_byte ptr_buf[8]; | |
408 | CORE_ADDR ptr_addr; | |
409 | ||
410 | ptr_addr = dyn_addr + (buf - bufstart) + arch_size / 8; | |
411 | if (target_read_memory (ptr_addr, ptr_buf, arch_size / 8) == 0) | |
412 | dyn_ptr = extract_typed_address (ptr_buf, | |
413 | builtin_type_void_data_ptr); | |
414 | *ptr = dyn_ptr; | |
415 | } | |
416 | return 1; | |
3a40aaa0 UW |
417 | } |
418 | } | |
419 | ||
420 | return 0; | |
421 | } | |
422 | ||
423 | ||
13437d4b KB |
424 | /* |
425 | ||
426 | LOCAL FUNCTION | |
427 | ||
428 | elf_locate_base -- locate the base address of dynamic linker structs | |
429 | for SVR4 elf targets. | |
430 | ||
431 | SYNOPSIS | |
432 | ||
433 | CORE_ADDR elf_locate_base (void) | |
434 | ||
435 | DESCRIPTION | |
436 | ||
437 | For SVR4 elf targets the address of the dynamic linker's runtime | |
438 | structure is contained within the dynamic info section in the | |
439 | executable file. The dynamic section is also mapped into the | |
440 | inferior address space. Because the runtime loader fills in the | |
441 | real address before starting the inferior, we have to read in the | |
442 | dynamic info section from the inferior address space. | |
443 | If there are any errors while trying to find the address, we | |
444 | silently return 0, otherwise the found address is returned. | |
445 | ||
446 | */ | |
447 | ||
448 | static CORE_ADDR | |
449 | elf_locate_base (void) | |
450 | { | |
3a40aaa0 UW |
451 | struct minimal_symbol *msymbol; |
452 | CORE_ADDR dyn_ptr; | |
13437d4b | 453 | |
65728c26 DJ |
454 | /* Look for DT_MIPS_RLD_MAP first. MIPS executables use this |
455 | instead of DT_DEBUG, although they sometimes contain an unused | |
456 | DT_DEBUG. */ | |
3a40aaa0 UW |
457 | if (scan_dyntag (DT_MIPS_RLD_MAP, exec_bfd, &dyn_ptr)) |
458 | { | |
459 | gdb_byte *pbuf; | |
460 | int pbuf_size = TYPE_LENGTH (builtin_type_void_data_ptr); | |
461 | pbuf = alloca (pbuf_size); | |
462 | /* DT_MIPS_RLD_MAP contains a pointer to the address | |
463 | of the dynamic link structure. */ | |
464 | if (target_read_memory (dyn_ptr, pbuf, pbuf_size)) | |
e499d0f1 | 465 | return 0; |
3a40aaa0 | 466 | return extract_typed_address (pbuf, builtin_type_void_data_ptr); |
e499d0f1 DJ |
467 | } |
468 | ||
65728c26 DJ |
469 | /* Find DT_DEBUG. */ |
470 | if (scan_dyntag (DT_DEBUG, exec_bfd, &dyn_ptr)) | |
471 | return dyn_ptr; | |
472 | ||
3a40aaa0 UW |
473 | /* This may be a static executable. Look for the symbol |
474 | conventionally named _r_debug, as a last resort. */ | |
475 | msymbol = lookup_minimal_symbol ("_r_debug", NULL, symfile_objfile); | |
476 | if (msymbol != NULL) | |
477 | return SYMBOL_VALUE_ADDRESS (msymbol); | |
13437d4b KB |
478 | |
479 | /* DT_DEBUG entry not found. */ | |
480 | return 0; | |
481 | } | |
482 | ||
13437d4b KB |
483 | /* |
484 | ||
485 | LOCAL FUNCTION | |
486 | ||
487 | locate_base -- locate the base address of dynamic linker structs | |
488 | ||
489 | SYNOPSIS | |
490 | ||
491 | CORE_ADDR locate_base (void) | |
492 | ||
493 | DESCRIPTION | |
494 | ||
495 | For both the SunOS and SVR4 shared library implementations, if the | |
496 | inferior executable has been linked dynamically, there is a single | |
497 | address somewhere in the inferior's data space which is the key to | |
498 | locating all of the dynamic linker's runtime structures. This | |
499 | address is the value of the debug base symbol. The job of this | |
500 | function is to find and return that address, or to return 0 if there | |
501 | is no such address (the executable is statically linked for example). | |
502 | ||
503 | For SunOS, the job is almost trivial, since the dynamic linker and | |
504 | all of it's structures are statically linked to the executable at | |
505 | link time. Thus the symbol for the address we are looking for has | |
506 | already been added to the minimal symbol table for the executable's | |
507 | objfile at the time the symbol file's symbols were read, and all we | |
508 | have to do is look it up there. Note that we explicitly do NOT want | |
509 | to find the copies in the shared library. | |
510 | ||
511 | The SVR4 version is a bit more complicated because the address | |
512 | is contained somewhere in the dynamic info section. We have to go | |
513 | to a lot more work to discover the address of the debug base symbol. | |
514 | Because of this complexity, we cache the value we find and return that | |
515 | value on subsequent invocations. Note there is no copy in the | |
516 | executable symbol tables. | |
517 | ||
518 | */ | |
519 | ||
520 | static CORE_ADDR | |
521 | locate_base (void) | |
522 | { | |
13437d4b KB |
523 | /* Check to see if we have a currently valid address, and if so, avoid |
524 | doing all this work again and just return the cached address. If | |
525 | we have no cached address, try to locate it in the dynamic info | |
d5a921c9 KB |
526 | section for ELF executables. There's no point in doing any of this |
527 | though if we don't have some link map offsets to work with. */ | |
13437d4b | 528 | |
d5a921c9 | 529 | if (debug_base == 0 && svr4_have_link_map_offsets ()) |
13437d4b KB |
530 | { |
531 | if (exec_bfd != NULL | |
532 | && bfd_get_flavour (exec_bfd) == bfd_target_elf_flavour) | |
533 | debug_base = elf_locate_base (); | |
13437d4b KB |
534 | } |
535 | return (debug_base); | |
13437d4b KB |
536 | } |
537 | ||
e4cd0d6a MK |
538 | /* Find the first element in the inferior's dynamic link map, and |
539 | return its address in the inferior. | |
13437d4b | 540 | |
e4cd0d6a MK |
541 | FIXME: Perhaps we should validate the info somehow, perhaps by |
542 | checking r_version for a known version number, or r_state for | |
543 | RT_CONSISTENT. */ | |
13437d4b KB |
544 | |
545 | static CORE_ADDR | |
e4cd0d6a | 546 | solib_svr4_r_map (void) |
13437d4b | 547 | { |
4b188b9f | 548 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); |
13437d4b | 549 | |
e4cd0d6a MK |
550 | return read_memory_typed_address (debug_base + lmo->r_map_offset, |
551 | builtin_type_void_data_ptr); | |
552 | } | |
13437d4b | 553 | |
e4cd0d6a MK |
554 | /* Find the link map for the dynamic linker (if it is not in the |
555 | normal list of loaded shared objects). */ | |
13437d4b | 556 | |
e4cd0d6a MK |
557 | static CORE_ADDR |
558 | solib_svr4_r_ldsomap (void) | |
559 | { | |
560 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); | |
561 | ULONGEST version; | |
13437d4b | 562 | |
e4cd0d6a MK |
563 | /* Check version, and return zero if `struct r_debug' doesn't have |
564 | the r_ldsomap member. */ | |
565 | version = read_memory_unsigned_integer (debug_base + lmo->r_version_offset, | |
566 | lmo->r_version_size); | |
567 | if (version < 2 || lmo->r_ldsomap_offset == -1) | |
568 | return 0; | |
13437d4b | 569 | |
e4cd0d6a MK |
570 | return read_memory_typed_address (debug_base + lmo->r_ldsomap_offset, |
571 | builtin_type_void_data_ptr); | |
13437d4b KB |
572 | } |
573 | ||
13437d4b KB |
574 | /* |
575 | ||
576 | LOCAL FUNCTION | |
577 | ||
578 | open_symbol_file_object | |
579 | ||
580 | SYNOPSIS | |
581 | ||
582 | void open_symbol_file_object (void *from_tty) | |
583 | ||
584 | DESCRIPTION | |
585 | ||
586 | If no open symbol file, attempt to locate and open the main symbol | |
587 | file. On SVR4 systems, this is the first link map entry. If its | |
588 | name is here, we can open it. Useful when attaching to a process | |
589 | without first loading its symbol file. | |
590 | ||
591 | If FROM_TTYP dereferences to a non-zero integer, allow messages to | |
592 | be printed. This parameter is a pointer rather than an int because | |
593 | open_symbol_file_object() is called via catch_errors() and | |
594 | catch_errors() requires a pointer argument. */ | |
595 | ||
596 | static int | |
597 | open_symbol_file_object (void *from_ttyp) | |
598 | { | |
599 | CORE_ADDR lm, l_name; | |
600 | char *filename; | |
601 | int errcode; | |
602 | int from_tty = *(int *)from_ttyp; | |
4b188b9f | 603 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); |
cfaefc65 AS |
604 | int l_name_size = TYPE_LENGTH (builtin_type_void_data_ptr); |
605 | gdb_byte *l_name_buf = xmalloc (l_name_size); | |
b8c9b27d | 606 | struct cleanup *cleanups = make_cleanup (xfree, l_name_buf); |
13437d4b KB |
607 | |
608 | if (symfile_objfile) | |
609 | if (!query ("Attempt to reload symbols from process? ")) | |
610 | return 0; | |
611 | ||
612 | if ((debug_base = locate_base ()) == 0) | |
613 | return 0; /* failed somehow... */ | |
614 | ||
615 | /* First link map member should be the executable. */ | |
e4cd0d6a MK |
616 | lm = solib_svr4_r_map (); |
617 | if (lm == 0) | |
13437d4b KB |
618 | return 0; /* failed somehow... */ |
619 | ||
620 | /* Read address of name from target memory to GDB. */ | |
cfaefc65 | 621 | read_memory (lm + lmo->l_name_offset, l_name_buf, l_name_size); |
13437d4b | 622 | |
cfaefc65 AS |
623 | /* Convert the address to host format. */ |
624 | l_name = extract_typed_address (l_name_buf, builtin_type_void_data_ptr); | |
13437d4b KB |
625 | |
626 | /* Free l_name_buf. */ | |
627 | do_cleanups (cleanups); | |
628 | ||
629 | if (l_name == 0) | |
630 | return 0; /* No filename. */ | |
631 | ||
632 | /* Now fetch the filename from target memory. */ | |
633 | target_read_string (l_name, &filename, SO_NAME_MAX_PATH_SIZE - 1, &errcode); | |
ea5bf0a1 | 634 | make_cleanup (xfree, filename); |
13437d4b KB |
635 | |
636 | if (errcode) | |
637 | { | |
8a3fe4f8 | 638 | warning (_("failed to read exec filename from attached file: %s"), |
13437d4b KB |
639 | safe_strerror (errcode)); |
640 | return 0; | |
641 | } | |
642 | ||
13437d4b | 643 | /* Have a pathname: read the symbol file. */ |
1adeb98a | 644 | symbol_file_add_main (filename, from_tty); |
13437d4b KB |
645 | |
646 | return 1; | |
647 | } | |
13437d4b | 648 | |
34439770 DJ |
649 | /* If no shared library information is available from the dynamic |
650 | linker, build a fallback list from other sources. */ | |
651 | ||
652 | static struct so_list * | |
653 | svr4_default_sos (void) | |
654 | { | |
655 | struct so_list *head = NULL; | |
656 | struct so_list **link_ptr = &head; | |
657 | ||
658 | if (debug_loader_offset_p) | |
659 | { | |
660 | struct so_list *new = XZALLOC (struct so_list); | |
661 | ||
662 | new->lm_info = xmalloc (sizeof (struct lm_info)); | |
663 | ||
664 | /* Nothing will ever check the cached copy of the link | |
665 | map if we set l_addr. */ | |
666 | new->lm_info->l_addr = debug_loader_offset; | |
667 | new->lm_info->lm = NULL; | |
668 | ||
669 | strncpy (new->so_name, debug_loader_name, SO_NAME_MAX_PATH_SIZE - 1); | |
670 | new->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0'; | |
671 | strcpy (new->so_original_name, new->so_name); | |
672 | ||
673 | *link_ptr = new; | |
674 | link_ptr = &new->next; | |
675 | } | |
676 | ||
677 | return head; | |
678 | } | |
679 | ||
13437d4b KB |
680 | /* LOCAL FUNCTION |
681 | ||
682 | current_sos -- build a list of currently loaded shared objects | |
683 | ||
684 | SYNOPSIS | |
685 | ||
686 | struct so_list *current_sos () | |
687 | ||
688 | DESCRIPTION | |
689 | ||
690 | Build a list of `struct so_list' objects describing the shared | |
691 | objects currently loaded in the inferior. This list does not | |
692 | include an entry for the main executable file. | |
693 | ||
694 | Note that we only gather information directly available from the | |
695 | inferior --- we don't examine any of the shared library files | |
696 | themselves. The declaration of `struct so_list' says which fields | |
697 | we provide values for. */ | |
698 | ||
699 | static struct so_list * | |
700 | svr4_current_sos (void) | |
701 | { | |
702 | CORE_ADDR lm; | |
703 | struct so_list *head = 0; | |
704 | struct so_list **link_ptr = &head; | |
e4cd0d6a | 705 | CORE_ADDR ldsomap = 0; |
13437d4b KB |
706 | |
707 | /* Make sure we've looked up the inferior's dynamic linker's base | |
708 | structure. */ | |
709 | if (! debug_base) | |
710 | { | |
711 | debug_base = locate_base (); | |
712 | ||
713 | /* If we can't find the dynamic linker's base structure, this | |
714 | must not be a dynamically linked executable. Hmm. */ | |
715 | if (! debug_base) | |
34439770 | 716 | return svr4_default_sos (); |
13437d4b KB |
717 | } |
718 | ||
719 | /* Walk the inferior's link map list, and build our list of | |
720 | `struct so_list' nodes. */ | |
e4cd0d6a | 721 | lm = solib_svr4_r_map (); |
34439770 | 722 | |
13437d4b KB |
723 | while (lm) |
724 | { | |
4b188b9f | 725 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); |
f4456994 | 726 | struct so_list *new = XZALLOC (struct so_list); |
b8c9b27d | 727 | struct cleanup *old_chain = make_cleanup (xfree, new); |
13437d4b | 728 | |
13437d4b | 729 | new->lm_info = xmalloc (sizeof (struct lm_info)); |
b8c9b27d | 730 | make_cleanup (xfree, new->lm_info); |
13437d4b | 731 | |
831004b7 | 732 | new->lm_info->l_addr = (CORE_ADDR)-1; |
f4456994 | 733 | new->lm_info->lm = xzalloc (lmo->link_map_size); |
b8c9b27d | 734 | make_cleanup (xfree, new->lm_info->lm); |
13437d4b KB |
735 | |
736 | read_memory (lm, new->lm_info->lm, lmo->link_map_size); | |
737 | ||
738 | lm = LM_NEXT (new); | |
739 | ||
740 | /* For SVR4 versions, the first entry in the link map is for the | |
741 | inferior executable, so we must ignore it. For some versions of | |
742 | SVR4, it has no name. For others (Solaris 2.3 for example), it | |
743 | does have a name, so we can no longer use a missing name to | |
744 | decide when to ignore it. */ | |
e4cd0d6a | 745 | if (IGNORE_FIRST_LINK_MAP_ENTRY (new) && ldsomap == 0) |
13437d4b KB |
746 | free_so (new); |
747 | else | |
748 | { | |
749 | int errcode; | |
750 | char *buffer; | |
751 | ||
752 | /* Extract this shared object's name. */ | |
753 | target_read_string (LM_NAME (new), &buffer, | |
754 | SO_NAME_MAX_PATH_SIZE - 1, &errcode); | |
755 | if (errcode != 0) | |
8a3fe4f8 AC |
756 | warning (_("Can't read pathname for load map: %s."), |
757 | safe_strerror (errcode)); | |
13437d4b KB |
758 | else |
759 | { | |
760 | strncpy (new->so_name, buffer, SO_NAME_MAX_PATH_SIZE - 1); | |
761 | new->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0'; | |
13437d4b KB |
762 | strcpy (new->so_original_name, new->so_name); |
763 | } | |
ea5bf0a1 | 764 | xfree (buffer); |
13437d4b KB |
765 | |
766 | /* If this entry has no name, or its name matches the name | |
767 | for the main executable, don't include it in the list. */ | |
768 | if (! new->so_name[0] | |
769 | || match_main (new->so_name)) | |
770 | free_so (new); | |
771 | else | |
772 | { | |
773 | new->next = 0; | |
774 | *link_ptr = new; | |
775 | link_ptr = &new->next; | |
776 | } | |
777 | } | |
778 | ||
e4cd0d6a MK |
779 | /* On Solaris, the dynamic linker is not in the normal list of |
780 | shared objects, so make sure we pick it up too. Having | |
781 | symbol information for the dynamic linker is quite crucial | |
782 | for skipping dynamic linker resolver code. */ | |
783 | if (lm == 0 && ldsomap == 0) | |
784 | lm = ldsomap = solib_svr4_r_ldsomap (); | |
785 | ||
13437d4b KB |
786 | discard_cleanups (old_chain); |
787 | } | |
788 | ||
34439770 DJ |
789 | if (head == NULL) |
790 | return svr4_default_sos (); | |
791 | ||
13437d4b KB |
792 | return head; |
793 | } | |
794 | ||
bc4a16ae EZ |
795 | /* Get the address of the link_map for a given OBJFILE. Loop through |
796 | the link maps, and return the address of the one corresponding to | |
797 | the given objfile. Note that this function takes into account that | |
798 | objfile can be the main executable, not just a shared library. The | |
799 | main executable has always an empty name field in the linkmap. */ | |
800 | ||
801 | CORE_ADDR | |
802 | svr4_fetch_objfile_link_map (struct objfile *objfile) | |
803 | { | |
804 | CORE_ADDR lm; | |
805 | ||
806 | if ((debug_base = locate_base ()) == 0) | |
807 | return 0; /* failed somehow... */ | |
808 | ||
809 | /* Position ourselves on the first link map. */ | |
e4cd0d6a | 810 | lm = solib_svr4_r_map (); |
bc4a16ae EZ |
811 | while (lm) |
812 | { | |
813 | /* Get info on the layout of the r_debug and link_map structures. */ | |
4b188b9f | 814 | struct link_map_offsets *lmo = svr4_fetch_link_map_offsets (); |
bc4a16ae EZ |
815 | int errcode; |
816 | char *buffer; | |
817 | struct lm_info objfile_lm_info; | |
818 | struct cleanup *old_chain; | |
819 | CORE_ADDR name_address; | |
cfaefc65 AS |
820 | int l_name_size = TYPE_LENGTH (builtin_type_void_data_ptr); |
821 | gdb_byte *l_name_buf = xmalloc (l_name_size); | |
bc4a16ae EZ |
822 | old_chain = make_cleanup (xfree, l_name_buf); |
823 | ||
824 | /* Set up the buffer to contain the portion of the link_map | |
825 | structure that gdb cares about. Note that this is not the | |
826 | whole link_map structure. */ | |
f4456994 | 827 | objfile_lm_info.lm = xzalloc (lmo->link_map_size); |
bc4a16ae | 828 | make_cleanup (xfree, objfile_lm_info.lm); |
bc4a16ae EZ |
829 | |
830 | /* Read the link map into our internal structure. */ | |
831 | read_memory (lm, objfile_lm_info.lm, lmo->link_map_size); | |
832 | ||
833 | /* Read address of name from target memory to GDB. */ | |
cfaefc65 | 834 | read_memory (lm + lmo->l_name_offset, l_name_buf, l_name_size); |
bc4a16ae | 835 | |
cfaefc65 AS |
836 | /* Extract this object's name. */ |
837 | name_address = extract_typed_address (l_name_buf, | |
838 | builtin_type_void_data_ptr); | |
bc4a16ae EZ |
839 | target_read_string (name_address, &buffer, |
840 | SO_NAME_MAX_PATH_SIZE - 1, &errcode); | |
841 | make_cleanup (xfree, buffer); | |
842 | if (errcode != 0) | |
8a3fe4f8 AC |
843 | warning (_("Can't read pathname for load map: %s."), |
844 | safe_strerror (errcode)); | |
bc4a16ae EZ |
845 | else |
846 | { | |
847 | /* Is this the linkmap for the file we want? */ | |
848 | /* If the file is not a shared library and has no name, | |
849 | we are sure it is the main executable, so we return that. */ | |
f52df7d9 MS |
850 | |
851 | if (buffer | |
852 | && ((strcmp (buffer, objfile->name) == 0) | |
853 | || (!(objfile->flags & OBJF_SHARED) | |
854 | && (strcmp (buffer, "") == 0)))) | |
bc4a16ae EZ |
855 | { |
856 | do_cleanups (old_chain); | |
857 | return lm; | |
858 | } | |
859 | } | |
cfaefc65 AS |
860 | /* Not the file we wanted, continue checking. */ |
861 | lm = extract_typed_address (objfile_lm_info.lm + lmo->l_next_offset, | |
862 | builtin_type_void_data_ptr); | |
bc4a16ae EZ |
863 | do_cleanups (old_chain); |
864 | } | |
865 | return 0; | |
866 | } | |
13437d4b KB |
867 | |
868 | /* On some systems, the only way to recognize the link map entry for | |
869 | the main executable file is by looking at its name. Return | |
870 | non-zero iff SONAME matches one of the known main executable names. */ | |
871 | ||
872 | static int | |
873 | match_main (char *soname) | |
874 | { | |
875 | char **mainp; | |
876 | ||
877 | for (mainp = main_name_list; *mainp != NULL; mainp++) | |
878 | { | |
879 | if (strcmp (soname, *mainp) == 0) | |
880 | return (1); | |
881 | } | |
882 | ||
883 | return (0); | |
884 | } | |
885 | ||
13437d4b KB |
886 | /* Return 1 if PC lies in the dynamic symbol resolution code of the |
887 | SVR4 run time loader. */ | |
13437d4b KB |
888 | static CORE_ADDR interp_text_sect_low; |
889 | static CORE_ADDR interp_text_sect_high; | |
890 | static CORE_ADDR interp_plt_sect_low; | |
891 | static CORE_ADDR interp_plt_sect_high; | |
892 | ||
7d522c90 | 893 | int |
d7fa2ae2 | 894 | svr4_in_dynsym_resolve_code (CORE_ADDR pc) |
13437d4b KB |
895 | { |
896 | return ((pc >= interp_text_sect_low && pc < interp_text_sect_high) | |
897 | || (pc >= interp_plt_sect_low && pc < interp_plt_sect_high) | |
898 | || in_plt_section (pc, NULL)); | |
899 | } | |
13437d4b | 900 | |
2f4950cd AC |
901 | /* Given an executable's ABFD and target, compute the entry-point |
902 | address. */ | |
903 | ||
904 | static CORE_ADDR | |
905 | exec_entry_point (struct bfd *abfd, struct target_ops *targ) | |
906 | { | |
907 | /* KevinB wrote ... for most targets, the address returned by | |
908 | bfd_get_start_address() is the entry point for the start | |
909 | function. But, for some targets, bfd_get_start_address() returns | |
910 | the address of a function descriptor from which the entry point | |
911 | address may be extracted. This address is extracted by | |
912 | gdbarch_convert_from_func_ptr_addr(). The method | |
913 | gdbarch_convert_from_func_ptr_addr() is the merely the identify | |
914 | function for targets which don't use function descriptors. */ | |
915 | return gdbarch_convert_from_func_ptr_addr (current_gdbarch, | |
916 | bfd_get_start_address (abfd), | |
917 | targ); | |
918 | } | |
13437d4b KB |
919 | |
920 | /* | |
921 | ||
922 | LOCAL FUNCTION | |
923 | ||
924 | enable_break -- arrange for dynamic linker to hit breakpoint | |
925 | ||
926 | SYNOPSIS | |
927 | ||
928 | int enable_break (void) | |
929 | ||
930 | DESCRIPTION | |
931 | ||
932 | Both the SunOS and the SVR4 dynamic linkers have, as part of their | |
933 | debugger interface, support for arranging for the inferior to hit | |
934 | a breakpoint after mapping in the shared libraries. This function | |
935 | enables that breakpoint. | |
936 | ||
937 | For SunOS, there is a special flag location (in_debugger) which we | |
938 | set to 1. When the dynamic linker sees this flag set, it will set | |
939 | a breakpoint at a location known only to itself, after saving the | |
940 | original contents of that place and the breakpoint address itself, | |
941 | in it's own internal structures. When we resume the inferior, it | |
942 | will eventually take a SIGTRAP when it runs into the breakpoint. | |
943 | We handle this (in a different place) by restoring the contents of | |
944 | the breakpointed location (which is only known after it stops), | |
945 | chasing around to locate the shared libraries that have been | |
946 | loaded, then resuming. | |
947 | ||
948 | For SVR4, the debugger interface structure contains a member (r_brk) | |
949 | which is statically initialized at the time the shared library is | |
950 | built, to the offset of a function (_r_debug_state) which is guaran- | |
951 | teed to be called once before mapping in a library, and again when | |
952 | the mapping is complete. At the time we are examining this member, | |
953 | it contains only the unrelocated offset of the function, so we have | |
954 | to do our own relocation. Later, when the dynamic linker actually | |
955 | runs, it relocates r_brk to be the actual address of _r_debug_state(). | |
956 | ||
957 | The debugger interface structure also contains an enumeration which | |
958 | is set to either RT_ADD or RT_DELETE prior to changing the mapping, | |
959 | depending upon whether or not the library is being mapped or unmapped, | |
960 | and then set to RT_CONSISTENT after the library is mapped/unmapped. | |
961 | */ | |
962 | ||
963 | static int | |
964 | enable_break (void) | |
965 | { | |
13437d4b KB |
966 | #ifdef BKPT_AT_SYMBOL |
967 | ||
968 | struct minimal_symbol *msymbol; | |
969 | char **bkpt_namep; | |
970 | asection *interp_sect; | |
971 | ||
972 | /* First, remove all the solib event breakpoints. Their addresses | |
973 | may have changed since the last time we ran the program. */ | |
974 | remove_solib_event_breakpoints (); | |
975 | ||
13437d4b KB |
976 | interp_text_sect_low = interp_text_sect_high = 0; |
977 | interp_plt_sect_low = interp_plt_sect_high = 0; | |
978 | ||
979 | /* Find the .interp section; if not found, warn the user and drop | |
980 | into the old breakpoint at symbol code. */ | |
981 | interp_sect = bfd_get_section_by_name (exec_bfd, ".interp"); | |
982 | if (interp_sect) | |
983 | { | |
984 | unsigned int interp_sect_size; | |
985 | char *buf; | |
8ad2fcde KB |
986 | CORE_ADDR load_addr = 0; |
987 | int load_addr_found = 0; | |
f8766ec1 | 988 | struct so_list *so; |
e4f7b8c8 | 989 | bfd *tmp_bfd = NULL; |
2f4950cd | 990 | struct target_ops *tmp_bfd_target; |
e4f7b8c8 MS |
991 | int tmp_fd = -1; |
992 | char *tmp_pathname = NULL; | |
13437d4b KB |
993 | CORE_ADDR sym_addr = 0; |
994 | ||
995 | /* Read the contents of the .interp section into a local buffer; | |
996 | the contents specify the dynamic linker this program uses. */ | |
997 | interp_sect_size = bfd_section_size (exec_bfd, interp_sect); | |
998 | buf = alloca (interp_sect_size); | |
999 | bfd_get_section_contents (exec_bfd, interp_sect, | |
1000 | buf, 0, interp_sect_size); | |
1001 | ||
1002 | /* Now we need to figure out where the dynamic linker was | |
1003 | loaded so that we can load its symbols and place a breakpoint | |
1004 | in the dynamic linker itself. | |
1005 | ||
1006 | This address is stored on the stack. However, I've been unable | |
1007 | to find any magic formula to find it for Solaris (appears to | |
1008 | be trivial on GNU/Linux). Therefore, we have to try an alternate | |
1009 | mechanism to find the dynamic linker's base address. */ | |
e4f7b8c8 | 1010 | |
34439770 DJ |
1011 | /* TODO drow/2006-09-12: This is somewhat fragile, because it |
1012 | relies on read_pc. On both Solaris and GNU/Linux we can use | |
1013 | the AT_BASE auxilliary entry, which GDB now knows how to | |
1014 | access, to find the base address. */ | |
1015 | ||
1016 | tmp_fd = solib_open (buf, &tmp_pathname); | |
e4f7b8c8 | 1017 | if (tmp_fd >= 0) |
9f76c2cd | 1018 | tmp_bfd = bfd_fopen (tmp_pathname, gnutarget, FOPEN_RB, tmp_fd); |
e4f7b8c8 | 1019 | |
13437d4b KB |
1020 | if (tmp_bfd == NULL) |
1021 | goto bkpt_at_symbol; | |
1022 | ||
1023 | /* Make sure the dynamic linker's really a useful object. */ | |
1024 | if (!bfd_check_format (tmp_bfd, bfd_object)) | |
1025 | { | |
8a3fe4f8 | 1026 | warning (_("Unable to grok dynamic linker %s as an object file"), buf); |
13437d4b KB |
1027 | bfd_close (tmp_bfd); |
1028 | goto bkpt_at_symbol; | |
1029 | } | |
1030 | ||
2f4950cd AC |
1031 | /* Now convert the TMP_BFD into a target. That way target, as |
1032 | well as BFD operations can be used. Note that closing the | |
1033 | target will also close the underlying bfd. */ | |
1034 | tmp_bfd_target = target_bfd_reopen (tmp_bfd); | |
1035 | ||
f8766ec1 KB |
1036 | /* On a running target, we can get the dynamic linker's base |
1037 | address from the shared library table. */ | |
2bbe3cc1 | 1038 | solib_add (NULL, 0, ¤t_target, auto_solib_add); |
f8766ec1 KB |
1039 | so = master_so_list (); |
1040 | while (so) | |
8ad2fcde | 1041 | { |
f8766ec1 | 1042 | if (strcmp (buf, so->so_original_name) == 0) |
8ad2fcde KB |
1043 | { |
1044 | load_addr_found = 1; | |
cc10cae3 | 1045 | load_addr = LM_ADDR_CHECK (so, tmp_bfd); |
8ad2fcde KB |
1046 | break; |
1047 | } | |
f8766ec1 | 1048 | so = so->next; |
8ad2fcde KB |
1049 | } |
1050 | ||
1051 | /* Otherwise we find the dynamic linker's base address by examining | |
1052 | the current pc (which should point at the entry point for the | |
1053 | dynamic linker) and subtracting the offset of the entry point. */ | |
1054 | if (!load_addr_found) | |
34439770 DJ |
1055 | { |
1056 | load_addr = (read_pc () | |
1057 | - exec_entry_point (tmp_bfd, tmp_bfd_target)); | |
1058 | debug_loader_name = xstrdup (buf); | |
1059 | debug_loader_offset_p = 1; | |
1060 | debug_loader_offset = load_addr; | |
2bbe3cc1 | 1061 | solib_add (NULL, 0, ¤t_target, auto_solib_add); |
34439770 | 1062 | } |
13437d4b KB |
1063 | |
1064 | /* Record the relocated start and end address of the dynamic linker | |
d7fa2ae2 | 1065 | text and plt section for svr4_in_dynsym_resolve_code. */ |
13437d4b KB |
1066 | interp_sect = bfd_get_section_by_name (tmp_bfd, ".text"); |
1067 | if (interp_sect) | |
1068 | { | |
1069 | interp_text_sect_low = | |
1070 | bfd_section_vma (tmp_bfd, interp_sect) + load_addr; | |
1071 | interp_text_sect_high = | |
1072 | interp_text_sect_low + bfd_section_size (tmp_bfd, interp_sect); | |
1073 | } | |
1074 | interp_sect = bfd_get_section_by_name (tmp_bfd, ".plt"); | |
1075 | if (interp_sect) | |
1076 | { | |
1077 | interp_plt_sect_low = | |
1078 | bfd_section_vma (tmp_bfd, interp_sect) + load_addr; | |
1079 | interp_plt_sect_high = | |
1080 | interp_plt_sect_low + bfd_section_size (tmp_bfd, interp_sect); | |
1081 | } | |
1082 | ||
1083 | /* Now try to set a breakpoint in the dynamic linker. */ | |
1084 | for (bkpt_namep = solib_break_names; *bkpt_namep != NULL; bkpt_namep++) | |
1085 | { | |
2bbe3cc1 | 1086 | sym_addr = bfd_lookup_symbol (tmp_bfd, *bkpt_namep); |
13437d4b KB |
1087 | if (sym_addr != 0) |
1088 | break; | |
1089 | } | |
1090 | ||
2bbe3cc1 DJ |
1091 | if (sym_addr != 0) |
1092 | /* Convert 'sym_addr' from a function pointer to an address. | |
1093 | Because we pass tmp_bfd_target instead of the current | |
1094 | target, this will always produce an unrelocated value. */ | |
1095 | sym_addr = gdbarch_convert_from_func_ptr_addr (current_gdbarch, | |
1096 | sym_addr, | |
1097 | tmp_bfd_target); | |
1098 | ||
2f4950cd AC |
1099 | /* We're done with both the temporary bfd and target. Remember, |
1100 | closing the target closes the underlying bfd. */ | |
1101 | target_close (tmp_bfd_target, 0); | |
13437d4b KB |
1102 | |
1103 | if (sym_addr != 0) | |
1104 | { | |
1105 | create_solib_event_breakpoint (load_addr + sym_addr); | |
1106 | return 1; | |
1107 | } | |
1108 | ||
1109 | /* For whatever reason we couldn't set a breakpoint in the dynamic | |
1110 | linker. Warn and drop into the old code. */ | |
1111 | bkpt_at_symbol: | |
518f9d3c | 1112 | xfree (tmp_pathname); |
82d03102 PG |
1113 | warning (_("Unable to find dynamic linker breakpoint function.\n" |
1114 | "GDB will be unable to debug shared library initializers\n" | |
1115 | "and track explicitly loaded dynamic code.")); | |
13437d4b | 1116 | } |
13437d4b | 1117 | |
e499d0f1 DJ |
1118 | /* Scan through the lists of symbols, trying to look up the symbol and |
1119 | set a breakpoint there. Terminate loop when we/if we succeed. */ | |
1120 | ||
1121 | for (bkpt_namep = solib_break_names; *bkpt_namep != NULL; bkpt_namep++) | |
1122 | { | |
1123 | msymbol = lookup_minimal_symbol (*bkpt_namep, NULL, symfile_objfile); | |
1124 | if ((msymbol != NULL) && (SYMBOL_VALUE_ADDRESS (msymbol) != 0)) | |
1125 | { | |
1126 | create_solib_event_breakpoint (SYMBOL_VALUE_ADDRESS (msymbol)); | |
1127 | return 1; | |
1128 | } | |
1129 | } | |
13437d4b | 1130 | |
13437d4b KB |
1131 | for (bkpt_namep = bkpt_names; *bkpt_namep != NULL; bkpt_namep++) |
1132 | { | |
1133 | msymbol = lookup_minimal_symbol (*bkpt_namep, NULL, symfile_objfile); | |
1134 | if ((msymbol != NULL) && (SYMBOL_VALUE_ADDRESS (msymbol) != 0)) | |
1135 | { | |
1136 | create_solib_event_breakpoint (SYMBOL_VALUE_ADDRESS (msymbol)); | |
1137 | return 1; | |
1138 | } | |
1139 | } | |
13437d4b KB |
1140 | #endif /* BKPT_AT_SYMBOL */ |
1141 | ||
542c95c2 | 1142 | return 0; |
13437d4b KB |
1143 | } |
1144 | ||
1145 | /* | |
1146 | ||
1147 | LOCAL FUNCTION | |
1148 | ||
1149 | special_symbol_handling -- additional shared library symbol handling | |
1150 | ||
1151 | SYNOPSIS | |
1152 | ||
1153 | void special_symbol_handling () | |
1154 | ||
1155 | DESCRIPTION | |
1156 | ||
1157 | Once the symbols from a shared object have been loaded in the usual | |
1158 | way, we are called to do any system specific symbol handling that | |
1159 | is needed. | |
1160 | ||
ab31aa69 | 1161 | For SunOS4, this consisted of grunging around in the dynamic |
13437d4b KB |
1162 | linkers structures to find symbol definitions for "common" symbols |
1163 | and adding them to the minimal symbol table for the runtime common | |
1164 | objfile. | |
1165 | ||
ab31aa69 KB |
1166 | However, for SVR4, there's nothing to do. |
1167 | ||
13437d4b KB |
1168 | */ |
1169 | ||
1170 | static void | |
1171 | svr4_special_symbol_handling (void) | |
1172 | { | |
13437d4b KB |
1173 | } |
1174 | ||
e2a44558 KB |
1175 | /* Relocate the main executable. This function should be called upon |
1176 | stopping the inferior process at the entry point to the program. | |
1177 | The entry point from BFD is compared to the PC and if they are | |
1178 | different, the main executable is relocated by the proper amount. | |
1179 | ||
1180 | As written it will only attempt to relocate executables which | |
1181 | lack interpreter sections. It seems likely that only dynamic | |
1182 | linker executables will get relocated, though it should work | |
1183 | properly for a position-independent static executable as well. */ | |
1184 | ||
1185 | static void | |
1186 | svr4_relocate_main_executable (void) | |
1187 | { | |
1188 | asection *interp_sect; | |
1189 | CORE_ADDR pc = read_pc (); | |
1190 | ||
1191 | /* Decide if the objfile needs to be relocated. As indicated above, | |
1192 | we will only be here when execution is stopped at the beginning | |
1193 | of the program. Relocation is necessary if the address at which | |
1194 | we are presently stopped differs from the start address stored in | |
1195 | the executable AND there's no interpreter section. The condition | |
1196 | regarding the interpreter section is very important because if | |
1197 | there *is* an interpreter section, execution will begin there | |
1198 | instead. When there is an interpreter section, the start address | |
1199 | is (presumably) used by the interpreter at some point to start | |
1200 | execution of the program. | |
1201 | ||
1202 | If there is an interpreter, it is normal for it to be set to an | |
1203 | arbitrary address at the outset. The job of finding it is | |
1204 | handled in enable_break(). | |
1205 | ||
1206 | So, to summarize, relocations are necessary when there is no | |
1207 | interpreter section and the start address obtained from the | |
1208 | executable is different from the address at which GDB is | |
1209 | currently stopped. | |
1210 | ||
1211 | [ The astute reader will note that we also test to make sure that | |
1212 | the executable in question has the DYNAMIC flag set. It is my | |
1213 | opinion that this test is unnecessary (undesirable even). It | |
1214 | was added to avoid inadvertent relocation of an executable | |
1215 | whose e_type member in the ELF header is not ET_DYN. There may | |
1216 | be a time in the future when it is desirable to do relocations | |
1217 | on other types of files as well in which case this condition | |
1218 | should either be removed or modified to accomodate the new file | |
1219 | type. (E.g, an ET_EXEC executable which has been built to be | |
1220 | position-independent could safely be relocated by the OS if | |
1221 | desired. It is true that this violates the ABI, but the ABI | |
1222 | has been known to be bent from time to time.) - Kevin, Nov 2000. ] | |
1223 | */ | |
1224 | ||
1225 | interp_sect = bfd_get_section_by_name (exec_bfd, ".interp"); | |
1226 | if (interp_sect == NULL | |
1227 | && (bfd_get_file_flags (exec_bfd) & DYNAMIC) != 0 | |
2f4950cd | 1228 | && (exec_entry_point (exec_bfd, &exec_ops) != pc)) |
e2a44558 KB |
1229 | { |
1230 | struct cleanup *old_chain; | |
1231 | struct section_offsets *new_offsets; | |
1232 | int i, changed; | |
1233 | CORE_ADDR displacement; | |
1234 | ||
1235 | /* It is necessary to relocate the objfile. The amount to | |
1236 | relocate by is simply the address at which we are stopped | |
1237 | minus the starting address from the executable. | |
1238 | ||
1239 | We relocate all of the sections by the same amount. This | |
1240 | behavior is mandated by recent editions of the System V ABI. | |
1241 | According to the System V Application Binary Interface, | |
1242 | Edition 4.1, page 5-5: | |
1243 | ||
1244 | ... Though the system chooses virtual addresses for | |
1245 | individual processes, it maintains the segments' relative | |
1246 | positions. Because position-independent code uses relative | |
1247 | addressesing between segments, the difference between | |
1248 | virtual addresses in memory must match the difference | |
1249 | between virtual addresses in the file. The difference | |
1250 | between the virtual address of any segment in memory and | |
1251 | the corresponding virtual address in the file is thus a | |
1252 | single constant value for any one executable or shared | |
1253 | object in a given process. This difference is the base | |
1254 | address. One use of the base address is to relocate the | |
1255 | memory image of the program during dynamic linking. | |
1256 | ||
1257 | The same language also appears in Edition 4.0 of the System V | |
1258 | ABI and is left unspecified in some of the earlier editions. */ | |
1259 | ||
2f4950cd | 1260 | displacement = pc - exec_entry_point (exec_bfd, &exec_ops); |
e2a44558 KB |
1261 | changed = 0; |
1262 | ||
13fc0c2f KB |
1263 | new_offsets = xcalloc (symfile_objfile->num_sections, |
1264 | sizeof (struct section_offsets)); | |
b8c9b27d | 1265 | old_chain = make_cleanup (xfree, new_offsets); |
e2a44558 KB |
1266 | |
1267 | for (i = 0; i < symfile_objfile->num_sections; i++) | |
1268 | { | |
1269 | if (displacement != ANOFFSET (symfile_objfile->section_offsets, i)) | |
1270 | changed = 1; | |
1271 | new_offsets->offsets[i] = displacement; | |
1272 | } | |
1273 | ||
1274 | if (changed) | |
1275 | objfile_relocate (symfile_objfile, new_offsets); | |
1276 | ||
1277 | do_cleanups (old_chain); | |
1278 | } | |
1279 | } | |
1280 | ||
13437d4b KB |
1281 | /* |
1282 | ||
1283 | GLOBAL FUNCTION | |
1284 | ||
1285 | svr4_solib_create_inferior_hook -- shared library startup support | |
1286 | ||
1287 | SYNOPSIS | |
1288 | ||
7095b863 | 1289 | void svr4_solib_create_inferior_hook () |
13437d4b KB |
1290 | |
1291 | DESCRIPTION | |
1292 | ||
1293 | When gdb starts up the inferior, it nurses it along (through the | |
1294 | shell) until it is ready to execute it's first instruction. At this | |
1295 | point, this function gets called via expansion of the macro | |
1296 | SOLIB_CREATE_INFERIOR_HOOK. | |
1297 | ||
1298 | For SunOS executables, this first instruction is typically the | |
1299 | one at "_start", or a similar text label, regardless of whether | |
1300 | the executable is statically or dynamically linked. The runtime | |
1301 | startup code takes care of dynamically linking in any shared | |
1302 | libraries, once gdb allows the inferior to continue. | |
1303 | ||
1304 | For SVR4 executables, this first instruction is either the first | |
1305 | instruction in the dynamic linker (for dynamically linked | |
1306 | executables) or the instruction at "start" for statically linked | |
1307 | executables. For dynamically linked executables, the system | |
1308 | first exec's /lib/libc.so.N, which contains the dynamic linker, | |
1309 | and starts it running. The dynamic linker maps in any needed | |
1310 | shared libraries, maps in the actual user executable, and then | |
1311 | jumps to "start" in the user executable. | |
1312 | ||
1313 | For both SunOS shared libraries, and SVR4 shared libraries, we | |
1314 | can arrange to cooperate with the dynamic linker to discover the | |
1315 | names of shared libraries that are dynamically linked, and the | |
1316 | base addresses to which they are linked. | |
1317 | ||
1318 | This function is responsible for discovering those names and | |
1319 | addresses, and saving sufficient information about them to allow | |
1320 | their symbols to be read at a later time. | |
1321 | ||
1322 | FIXME | |
1323 | ||
1324 | Between enable_break() and disable_break(), this code does not | |
1325 | properly handle hitting breakpoints which the user might have | |
1326 | set in the startup code or in the dynamic linker itself. Proper | |
1327 | handling will probably have to wait until the implementation is | |
1328 | changed to use the "breakpoint handler function" method. | |
1329 | ||
1330 | Also, what if child has exit()ed? Must exit loop somehow. | |
1331 | */ | |
1332 | ||
e2a44558 | 1333 | static void |
13437d4b KB |
1334 | svr4_solib_create_inferior_hook (void) |
1335 | { | |
e2a44558 KB |
1336 | /* Relocate the main executable if necessary. */ |
1337 | svr4_relocate_main_executable (); | |
1338 | ||
d5a921c9 | 1339 | if (!svr4_have_link_map_offsets ()) |
513f5903 | 1340 | return; |
d5a921c9 | 1341 | |
13437d4b | 1342 | if (!enable_break ()) |
542c95c2 | 1343 | return; |
13437d4b | 1344 | |
ab31aa69 KB |
1345 | #if defined(_SCO_DS) |
1346 | /* SCO needs the loop below, other systems should be using the | |
13437d4b KB |
1347 | special shared library breakpoints and the shared library breakpoint |
1348 | service routine. | |
1349 | ||
1350 | Now run the target. It will eventually hit the breakpoint, at | |
1351 | which point all of the libraries will have been mapped in and we | |
1352 | can go groveling around in the dynamic linker structures to find | |
1353 | out what we need to know about them. */ | |
1354 | ||
1355 | clear_proceed_status (); | |
c0236d92 | 1356 | stop_soon = STOP_QUIETLY; |
13437d4b KB |
1357 | stop_signal = TARGET_SIGNAL_0; |
1358 | do | |
1359 | { | |
39f77062 | 1360 | target_resume (pid_to_ptid (-1), 0, stop_signal); |
13437d4b KB |
1361 | wait_for_inferior (); |
1362 | } | |
1363 | while (stop_signal != TARGET_SIGNAL_TRAP); | |
c0236d92 | 1364 | stop_soon = NO_STOP_QUIETLY; |
ab31aa69 | 1365 | #endif /* defined(_SCO_DS) */ |
13437d4b KB |
1366 | } |
1367 | ||
1368 | static void | |
1369 | svr4_clear_solib (void) | |
1370 | { | |
1371 | debug_base = 0; | |
34439770 DJ |
1372 | debug_loader_offset_p = 0; |
1373 | debug_loader_offset = 0; | |
1374 | xfree (debug_loader_name); | |
1375 | debug_loader_name = NULL; | |
13437d4b KB |
1376 | } |
1377 | ||
1378 | static void | |
1379 | svr4_free_so (struct so_list *so) | |
1380 | { | |
b8c9b27d KB |
1381 | xfree (so->lm_info->lm); |
1382 | xfree (so->lm_info); | |
13437d4b KB |
1383 | } |
1384 | ||
6bb7be43 JB |
1385 | |
1386 | /* Clear any bits of ADDR that wouldn't fit in a target-format | |
1387 | data pointer. "Data pointer" here refers to whatever sort of | |
1388 | address the dynamic linker uses to manage its sections. At the | |
1389 | moment, we don't support shared libraries on any processors where | |
1390 | code and data pointers are different sizes. | |
1391 | ||
1392 | This isn't really the right solution. What we really need here is | |
1393 | a way to do arithmetic on CORE_ADDR values that respects the | |
1394 | natural pointer/address correspondence. (For example, on the MIPS, | |
1395 | converting a 32-bit pointer to a 64-bit CORE_ADDR requires you to | |
1396 | sign-extend the value. There, simply truncating the bits above | |
819844ad | 1397 | gdbarch_ptr_bit, as we do below, is no good.) This should probably |
6bb7be43 JB |
1398 | be a new gdbarch method or something. */ |
1399 | static CORE_ADDR | |
1400 | svr4_truncate_ptr (CORE_ADDR addr) | |
1401 | { | |
819844ad | 1402 | if (gdbarch_ptr_bit (current_gdbarch) == sizeof (CORE_ADDR) * 8) |
6bb7be43 JB |
1403 | /* We don't need to truncate anything, and the bit twiddling below |
1404 | will fail due to overflow problems. */ | |
1405 | return addr; | |
1406 | else | |
819844ad | 1407 | return addr & (((CORE_ADDR) 1 << gdbarch_ptr_bit (current_gdbarch)) - 1); |
6bb7be43 JB |
1408 | } |
1409 | ||
1410 | ||
749499cb KB |
1411 | static void |
1412 | svr4_relocate_section_addresses (struct so_list *so, | |
1413 | struct section_table *sec) | |
1414 | { | |
cc10cae3 AO |
1415 | sec->addr = svr4_truncate_ptr (sec->addr + LM_ADDR_CHECK (so, |
1416 | sec->bfd)); | |
1417 | sec->endaddr = svr4_truncate_ptr (sec->endaddr + LM_ADDR_CHECK (so, | |
1418 | sec->bfd)); | |
749499cb | 1419 | } |
4b188b9f | 1420 | \f |
749499cb | 1421 | |
4b188b9f | 1422 | /* Architecture-specific operations. */ |
6bb7be43 | 1423 | |
4b188b9f MK |
1424 | /* Per-architecture data key. */ |
1425 | static struct gdbarch_data *solib_svr4_data; | |
e5e2b9ff | 1426 | |
4b188b9f | 1427 | struct solib_svr4_ops |
e5e2b9ff | 1428 | { |
4b188b9f MK |
1429 | /* Return a description of the layout of `struct link_map'. */ |
1430 | struct link_map_offsets *(*fetch_link_map_offsets)(void); | |
1431 | }; | |
e5e2b9ff | 1432 | |
4b188b9f | 1433 | /* Return a default for the architecture-specific operations. */ |
e5e2b9ff | 1434 | |
4b188b9f MK |
1435 | static void * |
1436 | solib_svr4_init (struct obstack *obstack) | |
e5e2b9ff | 1437 | { |
4b188b9f | 1438 | struct solib_svr4_ops *ops; |
e5e2b9ff | 1439 | |
4b188b9f MK |
1440 | ops = OBSTACK_ZALLOC (obstack, struct solib_svr4_ops); |
1441 | ops->fetch_link_map_offsets = legacy_svr4_fetch_link_map_offsets_hook; | |
1442 | return ops; | |
e5e2b9ff KB |
1443 | } |
1444 | ||
4b188b9f MK |
1445 | /* Set the architecture-specific `struct link_map_offsets' fetcher for |
1446 | GDBARCH to FLMO. */ | |
1c4dcb57 | 1447 | |
21479ded | 1448 | void |
e5e2b9ff KB |
1449 | set_solib_svr4_fetch_link_map_offsets (struct gdbarch *gdbarch, |
1450 | struct link_map_offsets *(*flmo) (void)) | |
21479ded | 1451 | { |
4b188b9f MK |
1452 | struct solib_svr4_ops *ops = gdbarch_data (gdbarch, solib_svr4_data); |
1453 | ||
1454 | ops->fetch_link_map_offsets = flmo; | |
21479ded KB |
1455 | } |
1456 | ||
4b188b9f MK |
1457 | /* Fetch a link_map_offsets structure using the architecture-specific |
1458 | `struct link_map_offsets' fetcher. */ | |
1c4dcb57 | 1459 | |
4b188b9f MK |
1460 | static struct link_map_offsets * |
1461 | svr4_fetch_link_map_offsets (void) | |
21479ded | 1462 | { |
4b188b9f MK |
1463 | struct solib_svr4_ops *ops = gdbarch_data (current_gdbarch, solib_svr4_data); |
1464 | ||
1465 | gdb_assert (ops->fetch_link_map_offsets); | |
1466 | return ops->fetch_link_map_offsets (); | |
21479ded KB |
1467 | } |
1468 | ||
4b188b9f MK |
1469 | /* Return 1 if a link map offset fetcher has been defined, 0 otherwise. */ |
1470 | ||
1471 | static int | |
1472 | svr4_have_link_map_offsets (void) | |
1473 | { | |
1474 | struct solib_svr4_ops *ops = gdbarch_data (current_gdbarch, solib_svr4_data); | |
1475 | return (ops->fetch_link_map_offsets != NULL); | |
1476 | } | |
1477 | \f | |
1478 | ||
e4bbbda8 MK |
1479 | /* Most OS'es that have SVR4-style ELF dynamic libraries define a |
1480 | `struct r_debug' and a `struct link_map' that are binary compatible | |
1481 | with the origional SVR4 implementation. */ | |
1482 | ||
1483 | /* Fetch (and possibly build) an appropriate `struct link_map_offsets' | |
1484 | for an ILP32 SVR4 system. */ | |
1485 | ||
1486 | struct link_map_offsets * | |
1487 | svr4_ilp32_fetch_link_map_offsets (void) | |
1488 | { | |
1489 | static struct link_map_offsets lmo; | |
1490 | static struct link_map_offsets *lmp = NULL; | |
1491 | ||
1492 | if (lmp == NULL) | |
1493 | { | |
1494 | lmp = &lmo; | |
1495 | ||
e4cd0d6a MK |
1496 | lmo.r_version_offset = 0; |
1497 | lmo.r_version_size = 4; | |
e4bbbda8 | 1498 | lmo.r_map_offset = 4; |
e4cd0d6a | 1499 | lmo.r_ldsomap_offset = 20; |
e4bbbda8 MK |
1500 | |
1501 | /* Everything we need is in the first 20 bytes. */ | |
1502 | lmo.link_map_size = 20; | |
1503 | lmo.l_addr_offset = 0; | |
e4bbbda8 | 1504 | lmo.l_name_offset = 4; |
cc10cae3 | 1505 | lmo.l_ld_offset = 8; |
e4bbbda8 | 1506 | lmo.l_next_offset = 12; |
e4bbbda8 | 1507 | lmo.l_prev_offset = 16; |
e4bbbda8 MK |
1508 | } |
1509 | ||
1510 | return lmp; | |
1511 | } | |
1512 | ||
1513 | /* Fetch (and possibly build) an appropriate `struct link_map_offsets' | |
1514 | for an LP64 SVR4 system. */ | |
1515 | ||
1516 | struct link_map_offsets * | |
1517 | svr4_lp64_fetch_link_map_offsets (void) | |
1518 | { | |
1519 | static struct link_map_offsets lmo; | |
1520 | static struct link_map_offsets *lmp = NULL; | |
1521 | ||
1522 | if (lmp == NULL) | |
1523 | { | |
1524 | lmp = &lmo; | |
1525 | ||
e4cd0d6a MK |
1526 | lmo.r_version_offset = 0; |
1527 | lmo.r_version_size = 4; | |
e4bbbda8 | 1528 | lmo.r_map_offset = 8; |
e4cd0d6a | 1529 | lmo.r_ldsomap_offset = 40; |
e4bbbda8 MK |
1530 | |
1531 | /* Everything we need is in the first 40 bytes. */ | |
1532 | lmo.link_map_size = 40; | |
1533 | lmo.l_addr_offset = 0; | |
e4bbbda8 | 1534 | lmo.l_name_offset = 8; |
cc10cae3 | 1535 | lmo.l_ld_offset = 16; |
e4bbbda8 | 1536 | lmo.l_next_offset = 24; |
e4bbbda8 | 1537 | lmo.l_prev_offset = 32; |
e4bbbda8 MK |
1538 | } |
1539 | ||
1540 | return lmp; | |
1541 | } | |
1542 | \f | |
1543 | ||
7d522c90 | 1544 | struct target_so_ops svr4_so_ops; |
13437d4b | 1545 | |
3a40aaa0 UW |
1546 | /* Lookup global symbol for ELF DSOs linked with -Bsymbolic. Those DSOs have a |
1547 | different rule for symbol lookup. The lookup begins here in the DSO, not in | |
1548 | the main executable. */ | |
1549 | ||
1550 | static struct symbol * | |
1551 | elf_lookup_lib_symbol (const struct objfile *objfile, | |
1552 | const char *name, | |
1553 | const char *linkage_name, | |
1554 | const domain_enum domain, struct symtab **symtab) | |
1555 | { | |
1556 | if (objfile->obfd == NULL | |
1557 | || scan_dyntag (DT_SYMBOLIC, objfile->obfd, NULL) != 1) | |
1558 | return NULL; | |
1559 | ||
65728c26 | 1560 | return lookup_global_symbol_from_objfile |
3a40aaa0 UW |
1561 | (objfile, name, linkage_name, domain, symtab); |
1562 | } | |
1563 | ||
a78f21af AC |
1564 | extern initialize_file_ftype _initialize_svr4_solib; /* -Wmissing-prototypes */ |
1565 | ||
13437d4b KB |
1566 | void |
1567 | _initialize_svr4_solib (void) | |
1568 | { | |
4b188b9f MK |
1569 | solib_svr4_data = gdbarch_data_register_pre_init (solib_svr4_init); |
1570 | ||
749499cb | 1571 | svr4_so_ops.relocate_section_addresses = svr4_relocate_section_addresses; |
13437d4b KB |
1572 | svr4_so_ops.free_so = svr4_free_so; |
1573 | svr4_so_ops.clear_solib = svr4_clear_solib; | |
1574 | svr4_so_ops.solib_create_inferior_hook = svr4_solib_create_inferior_hook; | |
1575 | svr4_so_ops.special_symbol_handling = svr4_special_symbol_handling; | |
1576 | svr4_so_ops.current_sos = svr4_current_sos; | |
1577 | svr4_so_ops.open_symbol_file_object = open_symbol_file_object; | |
d7fa2ae2 | 1578 | svr4_so_ops.in_dynsym_resolve_code = svr4_in_dynsym_resolve_code; |
3a40aaa0 | 1579 | svr4_so_ops.lookup_lib_global_symbol = elf_lookup_lib_symbol; |
13437d4b KB |
1580 | |
1581 | /* FIXME: Don't do this here. *_gdbarch_init() should set so_ops. */ | |
1582 | current_target_so_ops = &svr4_so_ops; | |
1583 | } |