include/elf/
[deliverable/binutils-gdb.git] / gdb / solib-sunos.c
CommitLineData
ab31aa69 1/* Handle SunOS shared libraries for GDB, the GNU Debugger.
8dcef9cf 2
6aba47ca 3 Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000,
7b6bb8da 4 2001, 2004, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
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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
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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/>. */
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20
21#include "defs.h"
22
23#include <sys/types.h>
24#include <signal.h>
25#include "gdb_string.h"
26#include <sys/param.h>
27#include <fcntl.h>
28
8dcef9cf 29/* SunOS shared libs need the nlist structure. */
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30#include <a.out.h>
31#include <link.h>
32
33#include "symtab.h"
34#include "bfd.h"
35#include "symfile.h"
36#include "objfiles.h"
37#include "gdbcore.h"
38#include "inferior.h"
2020b7ab 39#include "gdbthread.h"
ab31aa69 40#include "solist.h"
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41#include "bcache.h"
42#include "regcache.h"
ab31aa69 43
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44/* The shared library implementation found on BSD a.out systems is
45 very similar to the SunOS implementation. However, the data
46 structures defined in <link.h> are named very differently. Make up
47 for those differences here. */
48
49#ifdef HAVE_STRUCT_SO_MAP_WITH_SOM_MEMBERS
50
51/* FIXME: Temporary until the equivalent defines have been removed
52 from all nm-*bsd*.h files. */
53#ifndef link_dynamic
54
55/* Map `struct link_map' and its members. */
56#define link_map so_map
57#define lm_addr som_addr
58#define lm_name som_path
59#define lm_next som_next
60
61/* Map `struct link_dynamic_2' and its members. */
62#define link_dynamic_2 section_dispatch_table
63#define ld_loaded sdt_loaded
64
65/* Map `struct rtc_symb' and its members. */
66#define rtc_symb rt_symbol
67#define rtc_sp rt_sp
68#define rtc_next rt_next
69
70/* Map `struct ld_debug' and its members. */
71#define ld_debug so_debug
72#define ldd_in_debugger dd_in_debugger
73#define ldd_bp_addr dd_bpt_addr
74#define ldd_bp_inst dd_bpt_shadow
75#define ldd_cp dd_cc
76
77/* Map `struct link_dynamic' and its members. */
78#define link_dynamic _dynamic
79#define ld_version d_version
80#define ldd d_debug
81#define ld_un d_un
82#define ld_2 d_sdt
83
84#endif
85
86#endif
87
c378eb4e 88/* Link map info to include in an allocated so_list entry. */
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89
90struct lm_info
91 {
92 /* Pointer to copy of link map from inferior. The type is char *
93 rather than void *, so that we may use byte offsets to find the
94 various fields without the need for a cast. */
95 char *lm;
96 };
97
98
c378eb4e 99/* Symbols which are used to locate the base of the link map structures. */
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100
101static char *debug_base_symbols[] =
102{
103 "_DYNAMIC",
104 "_DYNAMIC__MGC",
105 NULL
106};
107
108static char *main_name_list[] =
109{
110 "main_$main",
111 NULL
112};
113
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114/* Macro to extract an address from a solib structure. When GDB is
115 configured for some 32-bit targets (e.g. Solaris 2.7 sparc), BFD is
116 configured to handle 64-bit targets, so CORE_ADDR is 64 bits. We
117 have to extract only the significant bits of addresses to get the
118 right address when accessing the core file BFD.
119
120 Assume that the address is unsigned. */
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121
122#define SOLIB_EXTRACT_ADDRESS(MEMBER) \
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123 extract_unsigned_integer (&(MEMBER), sizeof (MEMBER), \
124 gdbarch_byte_order (target_gdbarch))
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125
126/* local data declarations */
127
128static struct link_dynamic dynamic_copy;
129static struct link_dynamic_2 ld_2_copy;
130static struct ld_debug debug_copy;
131static CORE_ADDR debug_addr;
132static CORE_ADDR flag_addr;
133
134#ifndef offsetof
135#define offsetof(TYPE, MEMBER) ((unsigned long) &((TYPE *)0)->MEMBER)
136#endif
137#define fieldsize(TYPE, MEMBER) (sizeof (((TYPE *)0)->MEMBER))
138
139/* link map access functions */
140
141static CORE_ADDR
142LM_ADDR (struct so_list *so)
143{
e17a4113 144 enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch);
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145 int lm_addr_offset = offsetof (struct link_map, lm_addr);
146 int lm_addr_size = fieldsize (struct link_map, lm_addr);
147
148 return (CORE_ADDR) extract_signed_integer (so->lm_info->lm + lm_addr_offset,
e17a4113 149 lm_addr_size, byte_order);
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150}
151
152static CORE_ADDR
153LM_NEXT (struct so_list *so)
154{
e17a4113 155 enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch);
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156 int lm_next_offset = offsetof (struct link_map, lm_next);
157 int lm_next_size = fieldsize (struct link_map, lm_next);
158
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159 /* Assume that the address is unsigned. */
160 return extract_unsigned_integer (so->lm_info->lm + lm_next_offset,
e17a4113 161 lm_next_size, byte_order);
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162}
163
164static CORE_ADDR
165LM_NAME (struct so_list *so)
166{
e17a4113 167 enum bfd_endian byte_order = gdbarch_byte_order (target_gdbarch);
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168 int lm_name_offset = offsetof (struct link_map, lm_name);
169 int lm_name_size = fieldsize (struct link_map, lm_name);
170
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171 /* Assume that the address is unsigned. */
172 return extract_unsigned_integer (so->lm_info->lm + lm_name_offset,
e17a4113 173 lm_name_size, byte_order);
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174}
175
c378eb4e 176static CORE_ADDR debug_base; /* Base of dynamic linker structures. */
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177
178/* Local function prototypes */
179
180static int match_main (char *);
181
182/* Allocate the runtime common object file. */
183
184static void
185allocate_rt_common_objfile (void)
186{
187 struct objfile *objfile;
188 struct objfile *last_one;
189
190 objfile = (struct objfile *) xmalloc (sizeof (struct objfile));
191 memset (objfile, 0, sizeof (struct objfile));
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192 objfile->psymbol_cache = bcache_xmalloc ();
193 objfile->macro_cache = bcache_xmalloc ();
10abe6bf 194 objfile->filename_cache = bcache_xmalloc ();
1ab21617 195 obstack_init (&objfile->objfile_obstack);
982526a1 196 objfile->name = xstrdup ("rt_common");
ab31aa69 197
c378eb4e 198 /* Add this file onto the tail of the linked list of other such files. */
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199
200 objfile->next = NULL;
201 if (object_files == NULL)
202 object_files = objfile;
203 else
204 {
205 for (last_one = object_files;
206 last_one->next;
207 last_one = last_one->next);
208 last_one->next = objfile;
209 }
210
211 rt_common_objfile = objfile;
212}
213
214/* Read all dynamically loaded common symbol definitions from the inferior
215 and put them into the minimal symbol table for the runtime common
216 objfile. */
217
218static void
219solib_add_common_symbols (CORE_ADDR rtc_symp)
220{
221 struct rtc_symb inferior_rtc_symb;
222 struct nlist inferior_rtc_nlist;
223 int len;
224 char *name;
225
226 /* Remove any runtime common symbols from previous runs. */
227
228 if (rt_common_objfile != NULL && rt_common_objfile->minimal_symbol_count)
229 {
4a146b47 230 obstack_free (&rt_common_objfile->objfile_obstack, 0);
1ab21617 231 obstack_init (&rt_common_objfile->objfile_obstack);
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232 rt_common_objfile->minimal_symbol_count = 0;
233 rt_common_objfile->msymbols = NULL;
15831452 234 terminate_minimal_symbol_table (rt_common_objfile);
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235 }
236
237 init_minimal_symbol_collection ();
238 make_cleanup_discard_minimal_symbols ();
239
240 while (rtc_symp)
241 {
242 read_memory (rtc_symp,
243 (char *) &inferior_rtc_symb,
244 sizeof (inferior_rtc_symb));
245 read_memory (SOLIB_EXTRACT_ADDRESS (inferior_rtc_symb.rtc_sp),
246 (char *) &inferior_rtc_nlist,
247 sizeof (inferior_rtc_nlist));
248 if (inferior_rtc_nlist.n_type == N_COMM)
249 {
250 /* FIXME: The length of the symbol name is not available, but in the
251 current implementation the common symbol is allocated immediately
c378eb4e 252 behind the name of the symbol. */
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253 len = inferior_rtc_nlist.n_value - inferior_rtc_nlist.n_un.n_strx;
254
255 name = xmalloc (len);
256 read_memory (SOLIB_EXTRACT_ADDRESS (inferior_rtc_nlist.n_un.n_name),
257 name, len);
258
c378eb4e 259 /* Allocate the runtime common objfile if necessary. */
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260 if (rt_common_objfile == NULL)
261 allocate_rt_common_objfile ();
262
263 prim_record_minimal_symbol (name, inferior_rtc_nlist.n_value,
264 mst_bss, rt_common_objfile);
265 xfree (name);
266 }
267 rtc_symp = SOLIB_EXTRACT_ADDRESS (inferior_rtc_symb.rtc_next);
268 }
269
270 /* Install any minimal symbols that have been collected as the current
271 minimal symbols for the runtime common objfile. */
272
273 install_minimal_symbols (rt_common_objfile);
274}
275
276
277/*
278
279 LOCAL FUNCTION
280
281 locate_base -- locate the base address of dynamic linker structs
282
283 SYNOPSIS
284
285 CORE_ADDR locate_base (void)
286
287 DESCRIPTION
288
289 For both the SunOS and SVR4 shared library implementations, if the
290 inferior executable has been linked dynamically, there is a single
291 address somewhere in the inferior's data space which is the key to
292 locating all of the dynamic linker's runtime structures. This
293 address is the value of the debug base symbol. The job of this
294 function is to find and return that address, or to return 0 if there
295 is no such address (the executable is statically linked for example).
296
297 For SunOS, the job is almost trivial, since the dynamic linker and
298 all of it's structures are statically linked to the executable at
299 link time. Thus the symbol for the address we are looking for has
300 already been added to the minimal symbol table for the executable's
301 objfile at the time the symbol file's symbols were read, and all we
302 have to do is look it up there. Note that we explicitly do NOT want
303 to find the copies in the shared library.
304
305 The SVR4 version is a bit more complicated because the address
306 is contained somewhere in the dynamic info section. We have to go
307 to a lot more work to discover the address of the debug base symbol.
308 Because of this complexity, we cache the value we find and return that
309 value on subsequent invocations. Note there is no copy in the
310 executable symbol tables.
311
312 */
313
314static CORE_ADDR
315locate_base (void)
316{
317 struct minimal_symbol *msymbol;
318 CORE_ADDR address = 0;
319 char **symbolp;
320
321 /* For SunOS, we want to limit the search for the debug base symbol to the
322 executable being debugged, since there is a duplicate named symbol in the
c378eb4e 323 shared library. We don't want the shared library versions. */
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324
325 for (symbolp = debug_base_symbols; *symbolp != NULL; symbolp++)
326 {
327 msymbol = lookup_minimal_symbol (*symbolp, NULL, symfile_objfile);
328 if ((msymbol != NULL) && (SYMBOL_VALUE_ADDRESS (msymbol) != 0))
329 {
330 address = SYMBOL_VALUE_ADDRESS (msymbol);
331 return (address);
332 }
333 }
334 return (0);
335}
336
337/*
338
339 LOCAL FUNCTION
340
341 first_link_map_member -- locate first member in dynamic linker's map
342
343 SYNOPSIS
344
345 static CORE_ADDR first_link_map_member (void)
346
347 DESCRIPTION
348
349 Find the first element in the inferior's dynamic link map, and
350 return its address in the inferior. This function doesn't copy the
351 link map entry itself into our address space; current_sos actually
352 does the reading. */
353
354static CORE_ADDR
355first_link_map_member (void)
356{
357 CORE_ADDR lm = 0;
358
359 read_memory (debug_base, (char *) &dynamic_copy, sizeof (dynamic_copy));
360 if (dynamic_copy.ld_version >= 2)
361 {
362 /* It is a version that we can deal with, so read in the secondary
c378eb4e 363 structure and find the address of the link map list from it. */
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364 read_memory (SOLIB_EXTRACT_ADDRESS (dynamic_copy.ld_un.ld_2),
365 (char *) &ld_2_copy, sizeof (struct link_dynamic_2));
366 lm = SOLIB_EXTRACT_ADDRESS (ld_2_copy.ld_loaded);
367 }
368 return (lm);
369}
370
371static int
372open_symbol_file_object (void *from_ttyp)
373{
374 return 1;
375}
376
377
378/* LOCAL FUNCTION
379
380 current_sos -- build a list of currently loaded shared objects
381
382 SYNOPSIS
383
384 struct so_list *current_sos ()
385
386 DESCRIPTION
387
388 Build a list of `struct so_list' objects describing the shared
389 objects currently loaded in the inferior. This list does not
390 include an entry for the main executable file.
391
392 Note that we only gather information directly available from the
393 inferior --- we don't examine any of the shared library files
394 themselves. The declaration of `struct so_list' says which fields
395 we provide values for. */
396
397static struct so_list *
398sunos_current_sos (void)
399{
400 CORE_ADDR lm;
401 struct so_list *head = 0;
402 struct so_list **link_ptr = &head;
403 int errcode;
404 char *buffer;
405
406 /* Make sure we've looked up the inferior's dynamic linker's base
407 structure. */
408 if (! debug_base)
409 {
410 debug_base = locate_base ();
411
412 /* If we can't find the dynamic linker's base structure, this
413 must not be a dynamically linked executable. Hmm. */
414 if (! debug_base)
415 return 0;
416 }
417
418 /* Walk the inferior's link map list, and build our list of
419 `struct so_list' nodes. */
420 lm = first_link_map_member ();
421 while (lm)
422 {
423 struct so_list *new
424 = (struct so_list *) xmalloc (sizeof (struct so_list));
425 struct cleanup *old_chain = make_cleanup (xfree, new);
426
427 memset (new, 0, sizeof (*new));
428
429 new->lm_info = xmalloc (sizeof (struct lm_info));
430 make_cleanup (xfree, new->lm_info);
431
432 new->lm_info->lm = xmalloc (sizeof (struct link_map));
433 make_cleanup (xfree, new->lm_info->lm);
434 memset (new->lm_info->lm, 0, sizeof (struct link_map));
435
436 read_memory (lm, new->lm_info->lm, sizeof (struct link_map));
437
438 lm = LM_NEXT (new);
439
440 /* Extract this shared object's name. */
441 target_read_string (LM_NAME (new), &buffer,
442 SO_NAME_MAX_PATH_SIZE - 1, &errcode);
443 if (errcode != 0)
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444 warning (_("Can't read pathname for load map: %s."),
445 safe_strerror (errcode));
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446 else
447 {
448 strncpy (new->so_name, buffer, SO_NAME_MAX_PATH_SIZE - 1);
449 new->so_name[SO_NAME_MAX_PATH_SIZE - 1] = '\0';
450 xfree (buffer);
451 strcpy (new->so_original_name, new->so_name);
452 }
453
454 /* If this entry has no name, or its name matches the name
455 for the main executable, don't include it in the list. */
456 if (! new->so_name[0]
457 || match_main (new->so_name))
458 free_so (new);
459 else
460 {
461 new->next = 0;
462 *link_ptr = new;
463 link_ptr = &new->next;
464 }
465
466 discard_cleanups (old_chain);
467 }
468
469 return head;
470}
471
472
473/* On some systems, the only way to recognize the link map entry for
474 the main executable file is by looking at its name. Return
475 non-zero iff SONAME matches one of the known main executable names. */
476
477static int
478match_main (char *soname)
479{
480 char **mainp;
481
482 for (mainp = main_name_list; *mainp != NULL; mainp++)
483 {
484 if (strcmp (soname, *mainp) == 0)
485 return (1);
486 }
487
488 return (0);
489}
490
491
492static int
493sunos_in_dynsym_resolve_code (CORE_ADDR pc)
494{
495 return 0;
496}
497
498/*
499
500 LOCAL FUNCTION
501
502 disable_break -- remove the "mapping changed" breakpoint
503
504 SYNOPSIS
505
506 static int disable_break ()
507
508 DESCRIPTION
509
510 Removes the breakpoint that gets hit when the dynamic linker
511 completes a mapping change.
512
513 */
514
515static int
516disable_break (void)
517{
c378eb4e 518 CORE_ADDR breakpoint_addr; /* Address where end bkpt is set. */
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519
520 int in_debugger = 0;
521
522 /* Read the debugger structure from the inferior to retrieve the
523 address of the breakpoint and the original contents of the
524 breakpoint address. Remove the breakpoint by writing the original
c378eb4e 525 contents back. */
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526
527 read_memory (debug_addr, (char *) &debug_copy, sizeof (debug_copy));
528
c378eb4e 529 /* Set `in_debugger' to zero now. */
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530
531 write_memory (flag_addr, (char *) &in_debugger, sizeof (in_debugger));
532
533 breakpoint_addr = SOLIB_EXTRACT_ADDRESS (debug_copy.ldd_bp_addr);
534 write_memory (breakpoint_addr, (char *) &debug_copy.ldd_bp_inst,
535 sizeof (debug_copy.ldd_bp_inst));
536
537 /* For the SVR4 version, we always know the breakpoint address. For the
538 SunOS version we don't know it until the above code is executed.
c378eb4e 539 Grumble if we are stopped anywhere besides the breakpoint address. */
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540
541 if (stop_pc != breakpoint_addr)
542 {
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543 warning (_("stopped at unknown breakpoint "
544 "while handling shared libraries"));
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545 }
546
547 return 1;
548}
549
550
551/*
552
553 LOCAL FUNCTION
554
555 enable_break -- arrange for dynamic linker to hit breakpoint
556
557 SYNOPSIS
558
559 int enable_break (void)
560
561 DESCRIPTION
562
563 Both the SunOS and the SVR4 dynamic linkers have, as part of their
564 debugger interface, support for arranging for the inferior to hit
565 a breakpoint after mapping in the shared libraries. This function
566 enables that breakpoint.
567
568 For SunOS, there is a special flag location (in_debugger) which we
569 set to 1. When the dynamic linker sees this flag set, it will set
570 a breakpoint at a location known only to itself, after saving the
571 original contents of that place and the breakpoint address itself,
572 in it's own internal structures. When we resume the inferior, it
573 will eventually take a SIGTRAP when it runs into the breakpoint.
574 We handle this (in a different place) by restoring the contents of
575 the breakpointed location (which is only known after it stops),
576 chasing around to locate the shared libraries that have been
577 loaded, then resuming.
578
579 For SVR4, the debugger interface structure contains a member (r_brk)
580 which is statically initialized at the time the shared library is
581 built, to the offset of a function (_r_debug_state) which is guaran-
582 teed to be called once before mapping in a library, and again when
583 the mapping is complete. At the time we are examining this member,
584 it contains only the unrelocated offset of the function, so we have
585 to do our own relocation. Later, when the dynamic linker actually
586 runs, it relocates r_brk to be the actual address of _r_debug_state().
587
588 The debugger interface structure also contains an enumeration which
589 is set to either RT_ADD or RT_DELETE prior to changing the mapping,
590 depending upon whether or not the library is being mapped or unmapped,
591 and then set to RT_CONSISTENT after the library is mapped/unmapped.
592 */
593
594static int
595enable_break (void)
596{
597 int success = 0;
598 int j;
599 int in_debugger;
600
c378eb4e 601 /* Get link_dynamic structure. */
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602
603 j = target_read_memory (debug_base, (char *) &dynamic_copy,
604 sizeof (dynamic_copy));
605 if (j)
606 {
607 /* unreadable */
608 return (0);
609 }
610
c378eb4e 611 /* Calc address of debugger interface structure. */
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612
613 debug_addr = SOLIB_EXTRACT_ADDRESS (dynamic_copy.ldd);
614
c378eb4e 615 /* Calc address of `in_debugger' member of debugger interface structure. */
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616
617 flag_addr = debug_addr + (CORE_ADDR) ((char *) &debug_copy.ldd_in_debugger -
618 (char *) &debug_copy);
619
620 /* Write a value of 1 to this member. */
621
622 in_debugger = 1;
623 write_memory (flag_addr, (char *) &in_debugger, sizeof (in_debugger));
624 success = 1;
625
626 return (success);
627}
628
629/*
630
631 LOCAL FUNCTION
632
633 special_symbol_handling -- additional shared library symbol handling
634
635 SYNOPSIS
636
637 void special_symbol_handling ()
638
639 DESCRIPTION
640
641 Once the symbols from a shared object have been loaded in the usual
642 way, we are called to do any system specific symbol handling that
643 is needed.
644
645 For SunOS4, this consists of grunging around in the dynamic
646 linkers structures to find symbol definitions for "common" symbols
647 and adding them to the minimal symbol table for the runtime common
648 objfile.
649
650 */
651
652static void
653sunos_special_symbol_handling (void)
654{
655 int j;
656
657 if (debug_addr == 0)
658 {
c378eb4e 659 /* Get link_dynamic structure. */
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660
661 j = target_read_memory (debug_base, (char *) &dynamic_copy,
662 sizeof (dynamic_copy));
663 if (j)
664 {
665 /* unreadable */
666 return;
667 }
668
c378eb4e 669 /* Calc address of debugger interface structure. */
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670 /* FIXME, this needs work for cross-debugging of core files
671 (byteorder, size, alignment, etc). */
672
673 debug_addr = SOLIB_EXTRACT_ADDRESS (dynamic_copy.ldd);
674 }
675
676 /* Read the debugger structure from the inferior, just to make sure
c378eb4e 677 we have a current copy. */
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678
679 j = target_read_memory (debug_addr, (char *) &debug_copy,
680 sizeof (debug_copy));
681 if (j)
682 return; /* unreadable */
683
c378eb4e 684 /* Get common symbol definitions for the loaded object. */
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685
686 if (debug_copy.ldd_cp)
687 {
688 solib_add_common_symbols (SOLIB_EXTRACT_ADDRESS (debug_copy.ldd_cp));
689 }
690}
691
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692/*
693
694 GLOBAL FUNCTION
695
696 sunos_solib_create_inferior_hook -- shared library startup support
697
698 SYNOPSIS
699
7095b863 700 void sunos_solib_create_inferior_hook ()
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701
702 DESCRIPTION
703
704 When gdb starts up the inferior, it nurses it along (through the
705 shell) until it is ready to execute it's first instruction. At this
706 point, this function gets called via expansion of the macro
707 SOLIB_CREATE_INFERIOR_HOOK.
708
709 For SunOS executables, this first instruction is typically the
710 one at "_start", or a similar text label, regardless of whether
711 the executable is statically or dynamically linked. The runtime
712 startup code takes care of dynamically linking in any shared
713 libraries, once gdb allows the inferior to continue.
714
715 For SVR4 executables, this first instruction is either the first
716 instruction in the dynamic linker (for dynamically linked
717 executables) or the instruction at "start" for statically linked
718 executables. For dynamically linked executables, the system
719 first exec's /lib/libc.so.N, which contains the dynamic linker,
720 and starts it running. The dynamic linker maps in any needed
721 shared libraries, maps in the actual user executable, and then
722 jumps to "start" in the user executable.
723
724 For both SunOS shared libraries, and SVR4 shared libraries, we
725 can arrange to cooperate with the dynamic linker to discover the
726 names of shared libraries that are dynamically linked, and the
727 base addresses to which they are linked.
728
729 This function is responsible for discovering those names and
730 addresses, and saving sufficient information about them to allow
731 their symbols to be read at a later time.
732
733 FIXME
734
735 Between enable_break() and disable_break(), this code does not
736 properly handle hitting breakpoints which the user might have
737 set in the startup code or in the dynamic linker itself. Proper
738 handling will probably have to wait until the implementation is
739 changed to use the "breakpoint handler function" method.
740
741 Also, what if child has exit()ed? Must exit loop somehow.
742 */
743
744static void
268a4a75 745sunos_solib_create_inferior_hook (int from_tty)
ab31aa69 746{
2020b7ab 747 struct thread_info *tp;
d6b48e9c 748 struct inferior *inf;
2020b7ab 749
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750 if ((debug_base = locate_base ()) == 0)
751 {
c378eb4e 752 /* Can't find the symbol or the executable is statically linked. */
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753 return;
754 }
755
756 if (!enable_break ())
757 {
8a3fe4f8 758 warning (_("shared library handler failed to enable breakpoint"));
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759 return;
760 }
761
762 /* SCO and SunOS need the loop below, other systems should be using the
763 special shared library breakpoints and the shared library breakpoint
764 service routine.
765
766 Now run the target. It will eventually hit the breakpoint, at
767 which point all of the libraries will have been mapped in and we
768 can go groveling around in the dynamic linker structures to find
c378eb4e 769 out what we need to know about them. */
ab31aa69 770
d6b48e9c 771 inf = current_inferior ();
2020b7ab 772 tp = inferior_thread ();
d6b48e9c 773
ab31aa69 774 clear_proceed_status ();
d6b48e9c 775
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776 inf->control.stop_soon = STOP_QUIETLY;
777 tp->suspend.stop_signal = TARGET_SIGNAL_0;
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778 do
779 {
16c381f0 780 target_resume (pid_to_ptid (-1), 0, tp->suspend.stop_signal);
ae123ec6 781 wait_for_inferior (0);
ab31aa69 782 }
16c381f0
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783 while (tp->suspend.stop_signal != TARGET_SIGNAL_TRAP);
784 inf->control.stop_soon = NO_STOP_QUIETLY;
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785
786 /* We are now either at the "mapping complete" breakpoint (or somewhere
787 else, a condition we aren't prepared to deal with anyway), so adjust
788 the PC as necessary after a breakpoint, disable the breakpoint, and
b4397864
UW
789 add any shared libraries that were mapped in.
790
791 Note that adjust_pc_after_break did not perform any PC adjustment,
792 as the breakpoint the inferior just hit was not inserted by GDB,
793 but by the dynamic loader itself, and is therefore not found on
794 the GDB software break point list. Thus we have to adjust the
795 PC here. */
ab31aa69 796
1cf3db46 797 if (gdbarch_decr_pc_after_break (target_gdbarch))
ab31aa69 798 {
1cf3db46 799 stop_pc -= gdbarch_decr_pc_after_break (target_gdbarch);
fb14de7b 800 regcache_write_pc (get_current_regcache (), stop_pc);
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801 }
802
803 if (!disable_break ())
804 {
8a3fe4f8 805 warning (_("shared library handler failed to disable breakpoint"));
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806 }
807
990f9fe3 808 solib_add ((char *) 0, 0, (struct target_ops *) 0, auto_solib_add);
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809}
810
811static void
812sunos_clear_solib (void)
813{
814 debug_base = 0;
815}
816
817static void
818sunos_free_so (struct so_list *so)
819{
820 xfree (so->lm_info->lm);
821 xfree (so->lm_info);
822}
823
824static void
825sunos_relocate_section_addresses (struct so_list *so,
0542c86d 826 struct target_section *sec)
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827{
828 sec->addr += LM_ADDR (so);
829 sec->endaddr += LM_ADDR (so);
830}
831
832static struct target_so_ops sunos_so_ops;
833
834void
835_initialize_sunos_solib (void)
836{
837 sunos_so_ops.relocate_section_addresses = sunos_relocate_section_addresses;
838 sunos_so_ops.free_so = sunos_free_so;
839 sunos_so_ops.clear_solib = sunos_clear_solib;
840 sunos_so_ops.solib_create_inferior_hook = sunos_solib_create_inferior_hook;
841 sunos_so_ops.special_symbol_handling = sunos_special_symbol_handling;
842 sunos_so_ops.current_sos = sunos_current_sos;
843 sunos_so_ops.open_symbol_file_object = open_symbol_file_object;
844 sunos_so_ops.in_dynsym_resolve_code = sunos_in_dynsym_resolve_code;
831a0c44 845 sunos_so_ops.bfd_open = solib_bfd_open;
ab31aa69 846
c378eb4e 847 /* FIXME: Don't do this here. *_gdbarch_init() should set so_ops. */
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848 current_target_so_ops = &sunos_so_ops;
849}
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