Commit | Line | Data |
---|---|---|
60cf7a85 KB |
1 | /* Handle AIX5 shared libraries for GDB, the GNU Debugger. |
2 | Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999, | |
3 | 2000, 2001 | |
4 | Free Software Foundation, Inc. | |
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 | |
10 | the Free Software Foundation; either version 2 of the License, or | |
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 | |
19 | along with this program; if not, write to the Free Software | |
20 | Foundation, Inc., 59 Temple Place - Suite 330, | |
21 | Boston, MA 02111-1307, USA. */ | |
22 | ||
23 | #include "defs.h" | |
24 | ||
25 | #include <sys/types.h> | |
26 | #include <signal.h> | |
27 | #include "gdb_string.h" | |
28 | #include <sys/param.h> | |
29 | #include <fcntl.h> | |
30 | #include <sys/procfs.h> | |
31 | ||
32 | #include "elf/external.h" | |
33 | ||
34 | #include "symtab.h" | |
35 | #include "bfd.h" | |
36 | #include "symfile.h" | |
37 | #include "objfiles.h" | |
38 | #include "gdbcore.h" | |
39 | #include "command.h" | |
40 | #include "target.h" | |
41 | #include "frame.h" | |
42 | #include "gdb_regex.h" | |
43 | #include "inferior.h" | |
44 | #include "environ.h" | |
45 | #include "language.h" | |
46 | #include "gdbcmd.h" | |
47 | ||
48 | #include "solist.h" | |
49 | #include "solib-svr4.h" | |
50 | ||
51 | /* Link map info to include in an allocated so_list entry */ | |
52 | ||
53 | enum maptype { | |
54 | MT_READONLY = 0, | |
55 | MT_READWRITE = 1, | |
56 | MT_LAST = 2 | |
57 | }; | |
58 | ||
59 | struct lm_info | |
60 | { | |
61 | struct | |
62 | { | |
63 | CORE_ADDR addr; /* base address */ | |
64 | CORE_ADDR size; /* size of mapped object */ | |
65 | CORE_ADDR offset; /* offset into mapped object */ | |
66 | long flags; /* MA_ protection and attribute flags */ | |
67 | CORE_ADDR gp; /* global pointer value */ | |
68 | } mapping[MT_LAST]; | |
69 | char *mapname; /* name in /proc/pid/object */ | |
70 | char *pathname; /* full pathname to object */ | |
71 | char *membername; /* member name in archive file */ | |
72 | }; | |
73 | ||
74 | /* On SVR4 systems, a list of symbols in the dynamic linker where | |
75 | GDB can try to place a breakpoint to monitor shared library | |
76 | events. | |
77 | ||
78 | If none of these symbols are found, or other errors occur, then | |
79 | SVR4 systems will fall back to using a symbol as the "startup | |
80 | mapping complete" breakpoint address. */ | |
81 | ||
82 | static char *solib_break_names[] = | |
83 | { | |
84 | "r_debug_state", | |
85 | "_r_debug_state", | |
86 | "_dl_debug_state", | |
87 | "rtld_db_dlactivity", | |
88 | NULL | |
89 | }; | |
90 | ||
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", | |
97 | "main", | |
98 | NULL | |
99 | }; | |
100 | ||
101 | static void aix5_relocate_main_executable (void); | |
102 | ||
103 | /* | |
104 | ||
105 | LOCAL FUNCTION | |
106 | ||
107 | bfd_lookup_symbol -- lookup the value for a specific symbol | |
108 | ||
109 | SYNOPSIS | |
110 | ||
111 | CORE_ADDR bfd_lookup_symbol (bfd *abfd, char *symname) | |
112 | ||
113 | DESCRIPTION | |
114 | ||
115 | An expensive way to lookup the value of a single symbol for | |
116 | bfd's that are only temporary anyway. This is used by the | |
117 | shared library support to find the address of the debugger | |
118 | interface structures in the shared library. | |
119 | ||
120 | Note that 0 is specifically allowed as an error return (no | |
121 | such symbol). | |
122 | */ | |
123 | ||
124 | static CORE_ADDR | |
125 | bfd_lookup_symbol (bfd *abfd, char *symname) | |
126 | { | |
127 | unsigned int storage_needed; | |
128 | asymbol *sym; | |
129 | asymbol **symbol_table; | |
130 | unsigned int number_of_symbols; | |
131 | unsigned int i; | |
132 | struct cleanup *back_to; | |
133 | CORE_ADDR symaddr = 0; | |
134 | ||
135 | storage_needed = bfd_get_symtab_upper_bound (abfd); | |
136 | ||
137 | if (storage_needed > 0) | |
138 | { | |
139 | symbol_table = (asymbol **) xmalloc (storage_needed); | |
140 | back_to = make_cleanup (free, (PTR) symbol_table); | |
141 | number_of_symbols = bfd_canonicalize_symtab (abfd, symbol_table); | |
142 | ||
143 | for (i = 0; i < number_of_symbols; i++) | |
144 | { | |
145 | sym = *symbol_table++; | |
146 | if (STREQ (sym->name, symname)) | |
147 | { | |
148 | /* Bfd symbols are section relative. */ | |
149 | symaddr = sym->value + sym->section->vma; | |
150 | break; | |
151 | } | |
152 | } | |
153 | do_cleanups (back_to); | |
154 | } | |
155 | ||
156 | if (symaddr) | |
157 | return symaddr; | |
158 | ||
159 | /* On FreeBSD, the dynamic linker is stripped by default. So we'll | |
160 | have to check the dynamic string table too. */ | |
161 | ||
162 | storage_needed = bfd_get_dynamic_symtab_upper_bound (abfd); | |
163 | /* FIXME: This problem should be addressed in BFD. */ | |
164 | #define REASONABLE_LIMIT 0x400000 | |
165 | if (storage_needed > REASONABLE_LIMIT) | |
166 | storage_needed = REASONABLE_LIMIT; | |
167 | ||
168 | if (storage_needed > 0) | |
169 | { | |
170 | symbol_table = (asymbol **) xmalloc (storage_needed); | |
171 | back_to = make_cleanup (free, (PTR) symbol_table); | |
172 | number_of_symbols = bfd_canonicalize_dynamic_symtab (abfd, symbol_table); | |
173 | ||
174 | for (i = 0; i < number_of_symbols; i++) | |
175 | { | |
176 | sym = *symbol_table++; | |
177 | if (STREQ (sym->name, symname)) | |
178 | { | |
179 | /* Bfd symbols are section relative. */ | |
180 | symaddr = sym->value + sym->section->vma; | |
181 | break; | |
182 | } | |
183 | } | |
184 | do_cleanups (back_to); | |
185 | } | |
186 | ||
187 | return symaddr; | |
188 | } | |
189 | ||
190 | ||
191 | /* Read /proc/PID/map and build a list of shared objects such that | |
192 | the pr_mflags value AND'd with MATCH_MASK is equal to MATCH_VAL. | |
193 | This gives us a convenient way to find all of the mappings that | |
194 | don't belong to the main executable or vice versa. Here are | |
195 | some of the possibilities: | |
196 | ||
197 | - Fetch all mappings: | |
198 | MATCH_MASK: 0 | |
199 | MATCH_VAL: 0 | |
200 | - Fetch all mappings except for main executable: | |
201 | MATCH_MASK: MA_MAINEXEC | |
202 | MATCH_VAL: 0 | |
203 | - Fetch only main executable: | |
204 | MATCH_MASK: MA_MAINEXEC | |
205 | MATCH_VAL: MA_MAINEXEC | |
206 | ||
207 | A cleanup chain for the list allocations done by this function should | |
208 | be established prior to calling build_so_list_from_mapfile(). */ | |
209 | ||
210 | static struct so_list * | |
211 | build_so_list_from_mapfile (int pid, long match_mask, long match_val) | |
212 | { | |
213 | char *mapbuf = NULL; | |
214 | struct prmap *prmap; | |
215 | int mapbuf_size; | |
216 | struct so_list *sos = NULL; | |
217 | ||
218 | { | |
219 | int mapbuf_allocation_size = 8192; | |
220 | char map_pathname[64]; | |
221 | int map_fd; | |
222 | ||
223 | /* Open the map file */ | |
224 | ||
225 | sprintf (map_pathname, "/proc/%d/map", pid); | |
226 | map_fd = open (map_pathname, O_RDONLY); | |
227 | if (map_fd < 0) | |
228 | return 0; | |
229 | ||
230 | /* Read the entire map file in */ | |
231 | do | |
232 | { | |
233 | if (mapbuf) | |
234 | { | |
235 | free (mapbuf); | |
236 | mapbuf_allocation_size *= 2; | |
237 | lseek (map_fd, 0, SEEK_SET); | |
238 | } | |
239 | mapbuf = xmalloc (mapbuf_allocation_size); | |
240 | mapbuf_size = read (map_fd, mapbuf, mapbuf_allocation_size); | |
241 | if (mapbuf_size < 0) | |
242 | { | |
243 | free (mapbuf); | |
244 | /* FIXME: This warrants an error or a warning of some sort */ | |
245 | return 0; | |
246 | } | |
247 | } while (mapbuf_size == mapbuf_allocation_size); | |
248 | ||
249 | close (map_fd); | |
250 | } | |
251 | ||
252 | for (prmap = (struct prmap *) mapbuf; | |
253 | (char *) prmap < mapbuf + mapbuf_size; | |
254 | prmap++) | |
255 | { | |
256 | char *mapname, *pathname, *membername; | |
257 | struct so_list *sop; | |
258 | enum maptype maptype; | |
259 | ||
260 | if (prmap->pr_size == 0) | |
261 | break; | |
262 | ||
263 | /* Skip to the next entry if there's no path associated with the | |
264 | map, unless we're looking for the kernel text region, in which | |
265 | case it's okay if there's no path. */ | |
266 | if ((prmap->pr_pathoff == 0 || prmap->pr_pathoff >= mapbuf_size) | |
267 | && ((match_mask & MA_KERNTEXT) == 0)) | |
268 | continue; | |
269 | ||
270 | /* Skip to the next entry if our match conditions don't hold. */ | |
271 | if ((prmap->pr_mflags & match_mask) != match_val) | |
272 | continue; | |
273 | ||
274 | mapname = prmap->pr_mapname; | |
275 | if (prmap->pr_pathoff == 0) | |
276 | { | |
277 | pathname = ""; | |
278 | membername = ""; | |
279 | } | |
280 | else | |
281 | { | |
282 | pathname = mapbuf + prmap->pr_pathoff; | |
283 | membername = pathname + strlen (pathname) + 1; | |
284 | } | |
285 | ||
286 | for (sop = sos; sop != NULL; sop = sop->next) | |
287 | if (strcmp (pathname, sop->lm_info->pathname) == 0 | |
288 | && strcmp (membername, sop->lm_info->membername) == 0) | |
289 | break; | |
290 | ||
291 | if (sop == NULL) | |
292 | { | |
293 | sop = xcalloc (sizeof (struct so_list), 1); | |
294 | make_cleanup (free, sop); | |
295 | sop->lm_info = xcalloc (sizeof (struct lm_info), 1); | |
296 | make_cleanup (free, sop->lm_info); | |
297 | sop->lm_info->mapname = xstrdup (mapname); | |
298 | make_cleanup (free, sop->lm_info->mapname); | |
299 | /* FIXME: Eliminate the pathname field once length restriction | |
300 | is lifted on so_name and so_original_name. */ | |
301 | sop->lm_info->pathname = xstrdup (pathname); | |
302 | make_cleanup (free, sop->lm_info->pathname); | |
303 | sop->lm_info->membername = xstrdup (membername); | |
304 | make_cleanup (free, sop->lm_info->membername); | |
305 | ||
306 | strncpy (sop->so_name, pathname, SO_NAME_MAX_PATH_SIZE - 1); | |
307 | sop->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0'; | |
308 | strcpy (sop->so_original_name, sop->so_name); | |
309 | ||
310 | sop->next = sos; | |
311 | sos = sop; | |
312 | } | |
313 | ||
314 | maptype = (prmap->pr_mflags & MA_WRITE) ? MT_READWRITE : MT_READONLY; | |
315 | sop->lm_info->mapping[maptype].addr = (CORE_ADDR) prmap->pr_vaddr; | |
316 | sop->lm_info->mapping[maptype].size = prmap->pr_size; | |
317 | sop->lm_info->mapping[maptype].offset = prmap->pr_off; | |
318 | sop->lm_info->mapping[maptype].flags = prmap->pr_mflags; | |
319 | sop->lm_info->mapping[maptype].gp = (CORE_ADDR) prmap->pr_gp; | |
320 | } | |
321 | ||
322 | free (mapbuf); | |
323 | return sos; | |
324 | } | |
325 | ||
326 | /* | |
327 | ||
328 | LOCAL FUNCTION | |
329 | ||
330 | open_symbol_file_object | |
331 | ||
332 | SYNOPSIS | |
333 | ||
334 | void open_symbol_file_object (void *from_tty) | |
335 | ||
336 | DESCRIPTION | |
337 | ||
338 | If no open symbol file, attempt to locate and open the main symbol | |
339 | file. | |
340 | ||
341 | If FROM_TTYP dereferences to a non-zero integer, allow messages to | |
342 | be printed. This parameter is a pointer rather than an int because | |
343 | open_symbol_file_object() is called via catch_errors() and | |
344 | catch_errors() requires a pointer argument. */ | |
345 | ||
346 | static int | |
347 | open_symbol_file_object (void *from_ttyp) | |
348 | { | |
349 | CORE_ADDR lm, l_name; | |
350 | char *filename; | |
351 | int errcode; | |
352 | int from_tty = *(int *)from_ttyp; | |
353 | struct cleanup *old_chain = make_cleanup (null_cleanup, 0); | |
354 | struct so_list *sos; | |
355 | ||
356 | sos = build_so_list_from_mapfile (PIDGET (inferior_pid), | |
357 | MA_MAINEXEC, MA_MAINEXEC); | |
358 | ||
359 | ||
360 | if (sos == NULL) | |
361 | { | |
362 | warning ("Could not find name of main executable in map file"); | |
363 | return 0; | |
364 | } | |
365 | ||
366 | symbol_file_command (sos->lm_info->pathname, from_tty); | |
367 | ||
368 | do_cleanups (old_chain); | |
369 | ||
370 | aix5_relocate_main_executable (); | |
371 | ||
372 | return 1; | |
373 | } | |
374 | ||
375 | /* LOCAL FUNCTION | |
376 | ||
377 | aix5_current_sos -- build a list of currently loaded shared objects | |
378 | ||
379 | SYNOPSIS | |
380 | ||
381 | struct so_list *aix5_current_sos () | |
382 | ||
383 | DESCRIPTION | |
384 | ||
385 | Build a list of `struct so_list' objects describing the shared | |
386 | objects currently loaded in the inferior. This list does not | |
387 | include an entry for the main executable file. | |
388 | ||
389 | Note that we only gather information directly available from the | |
390 | inferior --- we don't examine any of the shared library files | |
391 | themselves. The declaration of `struct so_list' says which fields | |
392 | we provide values for. */ | |
393 | ||
394 | static struct so_list * | |
395 | aix5_current_sos (void) | |
396 | { | |
397 | struct cleanup *old_chain = make_cleanup (null_cleanup, 0); | |
398 | struct so_list *sos; | |
399 | ||
400 | /* Fetch the list of mappings, excluding the main executable. */ | |
401 | sos = build_so_list_from_mapfile (PIDGET (inferior_pid), MA_MAINEXEC, 0); | |
402 | ||
403 | /* Reverse the list; it looks nicer when we print it if the mappings | |
404 | are in the same order as in the map file. */ | |
405 | if (sos) | |
406 | { | |
407 | struct so_list *next = sos->next; | |
408 | ||
409 | sos->next = 0; | |
410 | while (next) | |
411 | { | |
412 | struct so_list *prev = sos; | |
413 | ||
414 | sos = next; | |
415 | next = next->next; | |
416 | sos->next = prev; | |
417 | } | |
418 | } | |
419 | discard_cleanups (old_chain); | |
420 | return sos; | |
421 | } | |
422 | ||
423 | ||
424 | /* Return 1 if PC lies in the dynamic symbol resolution code of the | |
425 | SVR4 run time loader. */ | |
426 | ||
427 | static CORE_ADDR interp_text_sect_low; | |
428 | static CORE_ADDR interp_text_sect_high; | |
429 | static CORE_ADDR interp_plt_sect_low; | |
430 | static CORE_ADDR interp_plt_sect_high; | |
431 | ||
432 | /* FIXME: Does this belong here? (If it does, it ought to be renamed.) */ | |
433 | int | |
434 | in_svr4_dynsym_resolve_code (CORE_ADDR pc) | |
435 | { | |
436 | return ((pc >= interp_text_sect_low && pc < interp_text_sect_high) | |
437 | || (pc >= interp_plt_sect_low && pc < interp_plt_sect_high) | |
438 | || in_plt_section (pc, NULL)); | |
439 | } | |
440 | ||
441 | /* | |
442 | ||
443 | LOCAL FUNCTION | |
444 | ||
445 | enable_break -- arrange for dynamic linker to hit breakpoint | |
446 | ||
447 | SYNOPSIS | |
448 | ||
449 | int enable_break (void) | |
450 | ||
451 | DESCRIPTION | |
452 | ||
453 | Both the SunOS and the SVR4 dynamic linkers have, as part of their | |
454 | debugger interface, support for arranging for the inferior to hit | |
455 | a breakpoint after mapping in the shared libraries. This function | |
456 | enables that breakpoint. | |
457 | ||
458 | For SunOS, there is a special flag location (in_debugger) which we | |
459 | set to 1. When the dynamic linker sees this flag set, it will set | |
460 | a breakpoint at a location known only to itself, after saving the | |
461 | original contents of that place and the breakpoint address itself, | |
462 | in it's own internal structures. When we resume the inferior, it | |
463 | will eventually take a SIGTRAP when it runs into the breakpoint. | |
464 | We handle this (in a different place) by restoring the contents of | |
465 | the breakpointed location (which is only known after it stops), | |
466 | chasing around to locate the shared libraries that have been | |
467 | loaded, then resuming. | |
468 | ||
469 | For SVR4, the debugger interface structure contains a member (r_brk) | |
470 | which is statically initialized at the time the shared library is | |
471 | built, to the offset of a function (_r_debug_state) which is guaran- | |
472 | teed to be called once before mapping in a library, and again when | |
473 | the mapping is complete. At the time we are examining this member, | |
474 | it contains only the unrelocated offset of the function, so we have | |
475 | to do our own relocation. Later, when the dynamic linker actually | |
476 | runs, it relocates r_brk to be the actual address of _r_debug_state(). | |
477 | ||
478 | The debugger interface structure also contains an enumeration which | |
479 | is set to either RT_ADD or RT_DELETE prior to changing the mapping, | |
480 | depending upon whether or not the library is being mapped or unmapped, | |
481 | and then set to RT_CONSISTENT after the library is mapped/unmapped. | |
482 | */ | |
483 | ||
484 | static int | |
485 | enable_break (void) | |
486 | { | |
487 | int success = 0; | |
488 | ||
489 | struct minimal_symbol *msymbol; | |
490 | char **bkpt_namep; | |
491 | asection *interp_sect; | |
492 | ||
493 | /* First, remove all the solib event breakpoints. Their addresses | |
494 | may have changed since the last time we ran the program. */ | |
495 | remove_solib_event_breakpoints (); | |
496 | ||
497 | interp_text_sect_low = interp_text_sect_high = 0; | |
498 | interp_plt_sect_low = interp_plt_sect_high = 0; | |
499 | ||
500 | /* Find the .interp section; if not found, warn the user and drop | |
501 | into the old breakpoint at symbol code. */ | |
502 | interp_sect = bfd_get_section_by_name (exec_bfd, ".interp"); | |
503 | if (interp_sect) | |
504 | { | |
505 | unsigned int interp_sect_size; | |
506 | char *buf; | |
507 | CORE_ADDR load_addr; | |
508 | bfd *tmp_bfd; | |
509 | CORE_ADDR sym_addr = 0; | |
510 | ||
511 | /* Read the contents of the .interp section into a local buffer; | |
512 | the contents specify the dynamic linker this program uses. */ | |
513 | interp_sect_size = bfd_section_size (exec_bfd, interp_sect); | |
514 | buf = alloca (interp_sect_size); | |
515 | bfd_get_section_contents (exec_bfd, interp_sect, | |
516 | buf, 0, interp_sect_size); | |
517 | ||
518 | /* Now we need to figure out where the dynamic linker was | |
519 | loaded so that we can load its symbols and place a breakpoint | |
520 | in the dynamic linker itself. | |
521 | ||
522 | This address is stored on the stack. However, I've been unable | |
523 | to find any magic formula to find it for Solaris (appears to | |
524 | be trivial on GNU/Linux). Therefore, we have to try an alternate | |
525 | mechanism to find the dynamic linker's base address. */ | |
526 | tmp_bfd = bfd_openr (buf, gnutarget); | |
527 | if (tmp_bfd == NULL) | |
528 | goto bkpt_at_symbol; | |
529 | ||
530 | /* Make sure the dynamic linker's really a useful object. */ | |
531 | if (!bfd_check_format (tmp_bfd, bfd_object)) | |
532 | { | |
533 | warning ("Unable to grok dynamic linker %s as an object file", buf); | |
534 | bfd_close (tmp_bfd); | |
535 | goto bkpt_at_symbol; | |
536 | } | |
537 | ||
538 | /* We find the dynamic linker's base address by examining the | |
539 | current pc (which point at the entry point for the dynamic | |
540 | linker) and subtracting the offset of the entry point. */ | |
541 | load_addr = read_pc () - tmp_bfd->start_address; | |
542 | ||
543 | /* Record the relocated start and end address of the dynamic linker | |
544 | text and plt section for in_aix5_dynsym_resolve_code. */ | |
545 | interp_sect = bfd_get_section_by_name (tmp_bfd, ".text"); | |
546 | if (interp_sect) | |
547 | { | |
548 | interp_text_sect_low = | |
549 | bfd_section_vma (tmp_bfd, interp_sect) + load_addr; | |
550 | interp_text_sect_high = | |
551 | interp_text_sect_low + bfd_section_size (tmp_bfd, interp_sect); | |
552 | } | |
553 | interp_sect = bfd_get_section_by_name (tmp_bfd, ".plt"); | |
554 | if (interp_sect) | |
555 | { | |
556 | interp_plt_sect_low = | |
557 | bfd_section_vma (tmp_bfd, interp_sect) + load_addr; | |
558 | interp_plt_sect_high = | |
559 | interp_plt_sect_low + bfd_section_size (tmp_bfd, interp_sect); | |
560 | } | |
561 | ||
562 | /* Now try to set a breakpoint in the dynamic linker. */ | |
563 | for (bkpt_namep = solib_break_names; *bkpt_namep != NULL; bkpt_namep++) | |
564 | { | |
565 | sym_addr = bfd_lookup_symbol (tmp_bfd, *bkpt_namep); | |
566 | if (sym_addr != 0) | |
567 | break; | |
568 | } | |
569 | ||
570 | /* We're done with the temporary bfd. */ | |
571 | bfd_close (tmp_bfd); | |
572 | ||
573 | if (sym_addr != 0) | |
574 | { | |
575 | create_solib_event_breakpoint (load_addr + sym_addr); | |
576 | return 1; | |
577 | } | |
578 | ||
579 | /* For whatever reason we couldn't set a breakpoint in the dynamic | |
580 | linker. Warn and drop into the old code. */ | |
581 | bkpt_at_symbol: | |
582 | warning ("Unable to find dynamic linker breakpoint function.\nGDB will be unable to debug shared library initializers\nand track explicitly loaded dynamic code."); | |
583 | } | |
584 | ||
585 | /* Scan through the list of symbols, trying to look up the symbol and | |
586 | set a breakpoint there. Terminate loop when we/if we succeed. */ | |
587 | ||
588 | for (bkpt_namep = bkpt_names; *bkpt_namep != NULL; bkpt_namep++) | |
589 | { | |
590 | msymbol = lookup_minimal_symbol (*bkpt_namep, NULL, symfile_objfile); | |
591 | if ((msymbol != NULL) && (SYMBOL_VALUE_ADDRESS (msymbol) != 0)) | |
592 | { | |
593 | create_solib_event_breakpoint (SYMBOL_VALUE_ADDRESS (msymbol)); | |
594 | return 1; | |
595 | } | |
596 | } | |
597 | ||
598 | /* Nothing good happened. */ | |
599 | success = 0; | |
600 | ||
601 | return (success); | |
602 | } | |
603 | ||
604 | /* | |
605 | ||
606 | LOCAL FUNCTION | |
607 | ||
608 | special_symbol_handling -- additional shared library symbol handling | |
609 | ||
610 | SYNOPSIS | |
611 | ||
612 | void special_symbol_handling () | |
613 | ||
614 | DESCRIPTION | |
615 | ||
616 | Once the symbols from a shared object have been loaded in the usual | |
617 | way, we are called to do any system specific symbol handling that | |
618 | is needed. | |
619 | ||
620 | */ | |
621 | ||
622 | static void | |
623 | aix5_special_symbol_handling (void) | |
624 | { | |
625 | /* Nothing needed (yet) for AIX5. */ | |
626 | } | |
627 | ||
628 | #define SECTMAPMASK (~ (CORE_ADDR) 0x03ffffff) | |
629 | ||
630 | static void | |
631 | aix5_relocate_main_executable (void) | |
632 | { | |
633 | struct so_list *so; | |
634 | struct section_offsets *new_offsets; | |
635 | int i; | |
636 | int changed = 0; | |
637 | struct cleanup *old_chain = make_cleanup (null_cleanup, 0); | |
638 | ||
639 | /* Fetch the mappings for the main executable from the map file. */ | |
640 | so = build_so_list_from_mapfile (PIDGET (inferior_pid), | |
641 | MA_MAINEXEC, MA_MAINEXEC); | |
642 | ||
643 | /* Make sure we actually have some mappings to work with. */ | |
644 | if (so == NULL) | |
645 | { | |
646 | warning ("Could not find main executable in map file"); | |
647 | do_cleanups (old_chain); | |
648 | return; | |
649 | } | |
650 | ||
651 | /* Allocate the data structure which'll contain the new offsets to | |
652 | relocate by. Initialize it so it contains the current offsets. */ | |
653 | new_offsets = xcalloc (sizeof (struct section_offsets), | |
654 | symfile_objfile->num_sections); | |
655 | make_cleanup (free, new_offsets); | |
656 | for (i = 0; i < symfile_objfile->num_sections; i++) | |
657 | ANOFFSET (new_offsets, i) = ANOFFSET (symfile_objfile->section_offsets, i); | |
658 | ||
659 | /* Iterate over the mappings in the main executable and compute | |
660 | the new offset value as appropriate. */ | |
661 | for (i = 0; i < MT_LAST; i++) | |
662 | { | |
663 | CORE_ADDR increment = 0; | |
664 | struct obj_section *sect; | |
665 | bfd *obfd = symfile_objfile->obfd; | |
666 | ||
667 | ALL_OBJFILE_OSECTIONS (symfile_objfile, sect) | |
668 | { | |
669 | int flags = bfd_get_section_flags (obfd, sect->the_bfd_section); | |
670 | if (flags & SEC_ALLOC) | |
671 | { | |
672 | if (((so->lm_info->mapping[i].flags & MA_WRITE) == 0) | |
673 | == ((flags & SEC_READONLY) != 0)) | |
674 | { | |
675 | int idx = sect->the_bfd_section->index; | |
676 | ||
677 | if (increment == 0) | |
678 | increment = so->lm_info->mapping[i].addr | |
679 | - (bfd_section_vma (obfd, sect->the_bfd_section) | |
680 | & SECTMAPMASK); | |
681 | ||
682 | if (increment != ANOFFSET (new_offsets, idx)) | |
683 | { | |
684 | ANOFFSET (new_offsets, idx) = increment; | |
685 | changed = 1; | |
686 | } | |
687 | } | |
688 | } | |
689 | } | |
690 | } | |
691 | ||
692 | /* If any of the offsets have changed, then relocate the objfile. */ | |
693 | if (changed) | |
694 | objfile_relocate (symfile_objfile, new_offsets); | |
695 | ||
696 | /* Free up all the space we've allocated. */ | |
697 | do_cleanups (old_chain); | |
698 | } | |
699 | ||
700 | /* | |
701 | ||
702 | GLOBAL FUNCTION | |
703 | ||
704 | aix5_solib_create_inferior_hook -- shared library startup support | |
705 | ||
706 | SYNOPSIS | |
707 | ||
708 | void aix5_solib_create_inferior_hook() | |
709 | ||
710 | DESCRIPTION | |
711 | ||
712 | When gdb starts up the inferior, it nurses it along (through the | |
713 | shell) until it is ready to execute it's first instruction. At this | |
714 | point, this function gets called via expansion of the macro | |
715 | SOLIB_CREATE_INFERIOR_HOOK. | |
716 | ||
717 | For SVR4 executables, this first instruction is either the first | |
718 | instruction in the dynamic linker (for dynamically linked | |
719 | executables) or the instruction at "start" for statically linked | |
720 | executables. For dynamically linked executables, the system | |
721 | first exec's /lib/libc.so.N, which contains the dynamic linker, | |
722 | and starts it running. The dynamic linker maps in any needed | |
723 | shared libraries, maps in the actual user executable, and then | |
724 | jumps to "start" in the user executable. | |
725 | ||
726 | */ | |
727 | ||
728 | static void | |
729 | aix5_solib_create_inferior_hook (void) | |
730 | { | |
731 | aix5_relocate_main_executable (); | |
732 | ||
733 | if (!enable_break ()) | |
734 | { | |
735 | warning ("shared library handler failed to enable breakpoint"); | |
736 | return; | |
737 | } | |
738 | } | |
739 | ||
740 | static void | |
741 | aix5_clear_solib (void) | |
742 | { | |
743 | } | |
744 | ||
745 | static void | |
746 | aix5_free_so (struct so_list *so) | |
747 | { | |
748 | free (so->lm_info->mapname); | |
749 | free (so->lm_info->pathname); | |
750 | free (so->lm_info->membername); | |
751 | free (so->lm_info); | |
752 | } | |
753 | ||
754 | static void | |
755 | aix5_relocate_section_addresses (struct so_list *so, | |
756 | struct section_table *sec) | |
757 | { | |
758 | int flags = bfd_get_section_flags (sec->bfd, sec->the_bfd_section); | |
759 | ||
760 | if (flags & SEC_ALLOC) | |
761 | { | |
762 | int idx = (flags & SEC_READONLY) ? MT_READONLY : MT_READWRITE; | |
763 | CORE_ADDR addr = so->lm_info->mapping[idx].addr; | |
764 | ||
765 | sec->addr += addr; | |
766 | sec->endaddr += addr; | |
767 | } | |
768 | } | |
769 | ||
770 | /* Find the global pointer for the given function address ADDR. */ | |
771 | ||
772 | static CORE_ADDR | |
773 | aix5_find_global_pointer (CORE_ADDR addr) | |
774 | { | |
775 | struct so_list *sos, *so; | |
776 | CORE_ADDR global_pointer = 0; | |
777 | struct cleanup *old_chain = make_cleanup (null_cleanup, 0); | |
778 | ||
779 | sos = build_so_list_from_mapfile (PIDGET (inferior_pid), 0, 0); | |
780 | ||
781 | for (so = sos; so != NULL; so = so->next) | |
782 | { | |
783 | if (so->lm_info->mapping[MT_READONLY].addr <= addr | |
784 | && addr <= so->lm_info->mapping[MT_READONLY].addr | |
785 | + so->lm_info->mapping[MT_READONLY].size) | |
786 | { | |
787 | global_pointer = so->lm_info->mapping[MT_READWRITE].gp; | |
788 | break; | |
789 | } | |
790 | } | |
791 | ||
792 | do_cleanups (old_chain); | |
793 | ||
794 | return global_pointer; | |
795 | } | |
796 | ||
797 | /* Find the execute-only kernel region known as the gate page. This | |
798 | page is where the signal trampoline lives. It may be found by | |
799 | querying the map file and looking for the MA_KERNTEXT flag. */ | |
800 | static void | |
801 | aix5_find_gate_addresses (CORE_ADDR *start, CORE_ADDR *end) | |
802 | { | |
803 | struct so_list *so; | |
804 | struct cleanup *old_chain = make_cleanup (null_cleanup, 0); | |
805 | ||
806 | /* Fetch the mappings for the main executable from the map file. */ | |
807 | so = build_so_list_from_mapfile (PIDGET (inferior_pid), | |
808 | MA_KERNTEXT, MA_KERNTEXT); | |
809 | ||
810 | /* Make sure we actually have some mappings to work with. */ | |
811 | if (so == NULL) | |
812 | { | |
813 | warning ("Could not find gate page in map file"); | |
814 | *start = 0; | |
815 | *end = 0; | |
816 | do_cleanups (old_chain); | |
817 | return; | |
818 | } | |
819 | ||
820 | /* There should only be on kernel mapping for the gate page and | |
821 | it'll be in the read-only (even though it's execute-only) | |
822 | mapping in the lm_info struct. */ | |
823 | ||
824 | *start = so->lm_info->mapping[MT_READONLY].addr; | |
825 | *end = *start + so->lm_info->mapping[MT_READONLY].size; | |
826 | ||
827 | /* Free up all the space we've allocated. */ | |
828 | do_cleanups (old_chain); | |
829 | } | |
830 | ||
831 | /* From ia64-tdep.c. FIXME: If we end up using this for rs6000 too, | |
832 | we'll need to make the names match. */ | |
833 | extern CORE_ADDR (*native_find_global_pointer) (CORE_ADDR); | |
834 | ||
835 | /* From ia64-aix-tdep.c. Hook for finding the starting and | |
836 | ending gate page addresses. The only reason that this hook | |
837 | is in this file is because this is where the map file reading | |
838 | code is located. */ | |
839 | extern void (*aix5_find_gate_addresses_hook) (CORE_ADDR *, CORE_ADDR *); | |
840 | ||
841 | static struct target_so_ops aix5_so_ops; | |
842 | ||
843 | void | |
844 | _initialize_aix5_solib (void) | |
845 | { | |
846 | aix5_so_ops.relocate_section_addresses = aix5_relocate_section_addresses; | |
847 | aix5_so_ops.free_so = aix5_free_so; | |
848 | aix5_so_ops.clear_solib = aix5_clear_solib; | |
849 | aix5_so_ops.solib_create_inferior_hook = aix5_solib_create_inferior_hook; | |
850 | aix5_so_ops.special_symbol_handling = aix5_special_symbol_handling; | |
851 | aix5_so_ops.current_sos = aix5_current_sos; | |
852 | aix5_so_ops.open_symbol_file_object = open_symbol_file_object; | |
853 | ||
854 | native_find_global_pointer = aix5_find_global_pointer; | |
855 | aix5_find_gate_addresses_hook = aix5_find_gate_addresses; | |
856 | ||
857 | /* FIXME: Don't do this here. *_gdbarch_init() should set so_ops. */ | |
858 | current_target_so_ops = &aix5_so_ops; | |
859 | } | |
860 |