]> git.ipfire.org Git - thirdparty/binutils-gdb.git/blob - gdb/corelow.c
2010-08-18 Pedro Alves <pedro@codesourcery.com>
[thirdparty/binutils-gdb.git] / gdb / corelow.c
1 /* Core dump and executable file functions below target vector, for GDB.
2
3 Copyright (C) 1986, 1987, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
4 1998, 1999, 2000, 2001, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
5 Free Software Foundation, Inc.
6
7 This file is part of GDB.
8
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 3 of the License, or
12 (at your option) any later version.
13
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21
22 #include "defs.h"
23 #include "arch-utils.h"
24 #include "gdb_string.h"
25 #include <errno.h>
26 #include <signal.h>
27 #include <fcntl.h>
28 #ifdef HAVE_SYS_FILE_H
29 #include <sys/file.h> /* needed for F_OK and friends */
30 #endif
31 #include "frame.h" /* required by inferior.h */
32 #include "inferior.h"
33 #include "symtab.h"
34 #include "command.h"
35 #include "bfd.h"
36 #include "target.h"
37 #include "gdbcore.h"
38 #include "gdbthread.h"
39 #include "regcache.h"
40 #include "regset.h"
41 #include "symfile.h"
42 #include "exec.h"
43 #include "readline/readline.h"
44 #include "gdb_assert.h"
45 #include "exceptions.h"
46 #include "solib.h"
47 #include "filenames.h"
48 #include "progspace.h"
49 #include "objfiles.h"
50
51
52 #ifndef O_LARGEFILE
53 #define O_LARGEFILE 0
54 #endif
55
56 /* List of all available core_fns. On gdb startup, each core file
57 register reader calls deprecated_add_core_fns() to register
58 information on each core format it is prepared to read. */
59
60 static struct core_fns *core_file_fns = NULL;
61
62 /* The core_fns for a core file handler that is prepared to read the core
63 file currently open on core_bfd. */
64
65 static struct core_fns *core_vec = NULL;
66
67 /* FIXME: kettenis/20031023: Eventually this variable should
68 disappear. */
69
70 struct gdbarch *core_gdbarch = NULL;
71
72 /* Per-core data. Currently, only the section table. Note that these
73 target sections are *not* mapped in the current address spaces' set
74 of target sections --- those should come only from pure executable
75 or shared library bfds. The core bfd sections are an
76 implementation detail of the core target, just like ptrace is for
77 unix child targets. */
78 static struct target_section_table *core_data;
79
80 /* True if we needed to fake the pid of the loaded core inferior. */
81 static int core_has_fake_pid = 0;
82
83 static void core_files_info (struct target_ops *);
84
85 static struct core_fns *sniff_core_bfd (bfd *);
86
87 static int gdb_check_format (bfd *);
88
89 static void core_open (char *, int);
90
91 static void core_detach (struct target_ops *ops, char *, int);
92
93 static void core_close (int);
94
95 static void core_close_cleanup (void *ignore);
96
97 static void add_to_thread_list (bfd *, asection *, void *);
98
99 static void init_core_ops (void);
100
101 void _initialize_corelow (void);
102
103 static struct target_ops core_ops;
104
105 /* An arbitrary identifier for the core inferior. */
106 #define CORELOW_PID 1
107
108 /* Link a new core_fns into the global core_file_fns list. Called on gdb
109 startup by the _initialize routine in each core file register reader, to
110 register information about each format the the reader is prepared to
111 handle. */
112
113 void
114 deprecated_add_core_fns (struct core_fns *cf)
115 {
116 cf->next = core_file_fns;
117 core_file_fns = cf;
118 }
119
120 /* The default function that core file handlers can use to examine a
121 core file BFD and decide whether or not to accept the job of
122 reading the core file. */
123
124 int
125 default_core_sniffer (struct core_fns *our_fns, bfd *abfd)
126 {
127 int result;
128
129 result = (bfd_get_flavour (abfd) == our_fns -> core_flavour);
130 return (result);
131 }
132
133 /* Walk through the list of core functions to find a set that can
134 handle the core file open on ABFD. Default to the first one in the
135 list if nothing matches. Returns pointer to set that is
136 selected. */
137
138 static struct core_fns *
139 sniff_core_bfd (bfd *abfd)
140 {
141 struct core_fns *cf;
142 struct core_fns *yummy = NULL;
143 int matches = 0;;
144
145 /* Don't sniff if we have support for register sets in CORE_GDBARCH. */
146 if (core_gdbarch && gdbarch_regset_from_core_section_p (core_gdbarch))
147 return NULL;
148
149 for (cf = core_file_fns; cf != NULL; cf = cf->next)
150 {
151 if (cf->core_sniffer (cf, abfd))
152 {
153 yummy = cf;
154 matches++;
155 }
156 }
157 if (matches > 1)
158 {
159 warning (_("\"%s\": ambiguous core format, %d handlers match"),
160 bfd_get_filename (abfd), matches);
161 }
162 else if (matches == 0)
163 {
164 warning (_("\"%s\": no core file handler recognizes format, using default"),
165 bfd_get_filename (abfd));
166 }
167 if (yummy == NULL)
168 {
169 yummy = core_file_fns;
170 }
171 return (yummy);
172 }
173
174 /* The default is to reject every core file format we see. Either
175 BFD has to recognize it, or we have to provide a function in the
176 core file handler that recognizes it. */
177
178 int
179 default_check_format (bfd *abfd)
180 {
181 return (0);
182 }
183
184 /* Attempt to recognize core file formats that BFD rejects. */
185
186 static int
187 gdb_check_format (bfd *abfd)
188 {
189 struct core_fns *cf;
190
191 for (cf = core_file_fns; cf != NULL; cf = cf->next)
192 {
193 if (cf->check_format (abfd))
194 {
195 return (1);
196 }
197 }
198 return (0);
199 }
200
201 /* Discard all vestiges of any previous core file and mark data and stack
202 spaces as empty. */
203
204 static void
205 core_close (int quitting)
206 {
207 char *name;
208
209 if (core_bfd)
210 {
211 int pid = ptid_get_pid (inferior_ptid);
212 inferior_ptid = null_ptid; /* Avoid confusion from thread stuff */
213 exit_inferior_silent (pid);
214
215 /* Clear out solib state while the bfd is still open. See
216 comments in clear_solib in solib.c. */
217 clear_solib ();
218
219 xfree (core_data->sections);
220 xfree (core_data);
221 core_data = NULL;
222 core_has_fake_pid = 0;
223
224 name = bfd_get_filename (core_bfd);
225 gdb_bfd_close_or_warn (core_bfd);
226 xfree (name);
227 core_bfd = NULL;
228 }
229 core_vec = NULL;
230 core_gdbarch = NULL;
231 }
232
233 static void
234 core_close_cleanup (void *ignore)
235 {
236 core_close (0/*ignored*/);
237 }
238
239 /* Look for sections whose names start with `.reg/' so that we can extract the
240 list of threads in a core file. */
241
242 static void
243 add_to_thread_list (bfd *abfd, asection *asect, void *reg_sect_arg)
244 {
245 ptid_t ptid;
246 int core_tid;
247 int pid, lwpid;
248 asection *reg_sect = (asection *) reg_sect_arg;
249
250 if (strncmp (bfd_section_name (abfd, asect), ".reg/", 5) != 0)
251 return;
252
253 core_tid = atoi (bfd_section_name (abfd, asect) + 5);
254
255 pid = bfd_core_file_pid (core_bfd);
256 if (pid == 0)
257 {
258 core_has_fake_pid = 1;
259 pid = CORELOW_PID;
260 }
261
262 lwpid = core_tid;
263
264 if (current_inferior ()->pid == 0)
265 inferior_appeared (current_inferior (), pid);
266
267 ptid = ptid_build (pid, lwpid, 0);
268
269 add_thread (ptid);
270
271 /* Warning, Will Robinson, looking at BFD private data! */
272
273 if (reg_sect != NULL
274 && asect->filepos == reg_sect->filepos) /* Did we find .reg? */
275 inferior_ptid = ptid; /* Yes, make it current */
276 }
277
278 /* This routine opens and sets up the core file bfd. */
279
280 static void
281 core_open (char *filename, int from_tty)
282 {
283 const char *p;
284 int siggy;
285 struct cleanup *old_chain;
286 char *temp;
287 bfd *temp_bfd;
288 int scratch_chan;
289 int flags;
290
291 target_preopen (from_tty);
292 if (!filename)
293 {
294 if (core_bfd)
295 error (_("No core file specified. (Use `detach' to stop debugging a core file.)"));
296 else
297 error (_("No core file specified."));
298 }
299
300 filename = tilde_expand (filename);
301 if (!IS_ABSOLUTE_PATH(filename))
302 {
303 temp = concat (current_directory, "/", filename, (char *)NULL);
304 xfree (filename);
305 filename = temp;
306 }
307
308 old_chain = make_cleanup (xfree, filename);
309
310 flags = O_BINARY | O_LARGEFILE;
311 if (write_files)
312 flags |= O_RDWR;
313 else
314 flags |= O_RDONLY;
315 scratch_chan = open (filename, flags, 0);
316 if (scratch_chan < 0)
317 perror_with_name (filename);
318
319 temp_bfd = bfd_fopen (filename, gnutarget,
320 write_files ? FOPEN_RUB : FOPEN_RB,
321 scratch_chan);
322 if (temp_bfd == NULL)
323 perror_with_name (filename);
324
325 if (!bfd_check_format (temp_bfd, bfd_core)
326 && !gdb_check_format (temp_bfd))
327 {
328 /* Do it after the err msg */
329 /* FIXME: should be checking for errors from bfd_close (for one thing,
330 on error it does not free all the storage associated with the
331 bfd). */
332 make_cleanup_bfd_close (temp_bfd);
333 error (_("\"%s\" is not a core dump: %s"),
334 filename, bfd_errmsg (bfd_get_error ()));
335 }
336
337 /* Looks semi-reasonable. Toss the old core file and work on the new. */
338
339 discard_cleanups (old_chain); /* Don't free filename any more */
340 unpush_target (&core_ops);
341 core_bfd = temp_bfd;
342 old_chain = make_cleanup (core_close_cleanup, 0 /*ignore*/);
343
344 /* FIXME: kettenis/20031023: This is very dangerous. The
345 CORE_GDBARCH that results from this call may very well be
346 different from CURRENT_GDBARCH. However, its methods may only
347 work if it is selected as the current architecture, because they
348 rely on swapped data (see gdbarch.c). We should get rid of that
349 swapped data. */
350 core_gdbarch = gdbarch_from_bfd (core_bfd);
351
352 /* Find a suitable core file handler to munch on core_bfd */
353 core_vec = sniff_core_bfd (core_bfd);
354
355 validate_files ();
356
357 core_data = XZALLOC (struct target_section_table);
358
359 /* Find the data section */
360 if (build_section_table (core_bfd,
361 &core_data->sections, &core_data->sections_end))
362 error (_("\"%s\": Can't find sections: %s"),
363 bfd_get_filename (core_bfd), bfd_errmsg (bfd_get_error ()));
364
365 /* If we have no exec file, try to set the architecture from the
366 core file. We don't do this unconditionally since an exec file
367 typically contains more information that helps us determine the
368 architecture than a core file. */
369 if (!exec_bfd)
370 set_gdbarch_from_file (core_bfd);
371
372 push_target (&core_ops);
373 discard_cleanups (old_chain);
374
375 /* Do this before acknowledging the inferior, so if
376 post_create_inferior throws (can happen easilly if you're loading
377 a core file with the wrong exec), we aren't left with threads
378 from the previous inferior. */
379 init_thread_list ();
380
381 inferior_ptid = null_ptid;
382 core_has_fake_pid = 0;
383
384 /* Need to flush the register cache (and the frame cache) from a
385 previous debug session. If inferior_ptid ends up the same as the
386 last debug session --- e.g., b foo; run; gcore core1; step; gcore
387 core2; core core1; core core2 --- then there's potential for
388 get_current_regcache to return the cached regcache of the
389 previous session, and the frame cache being stale. */
390 registers_changed ();
391
392 /* Build up thread list from BFD sections, and possibly set the
393 current thread to the .reg/NN section matching the .reg
394 section. */
395 bfd_map_over_sections (core_bfd, add_to_thread_list,
396 bfd_get_section_by_name (core_bfd, ".reg"));
397
398 if (ptid_equal (inferior_ptid, null_ptid))
399 {
400 /* Either we found no .reg/NN section, and hence we have a
401 non-threaded core (single-threaded, from gdb's perspective),
402 or for some reason add_to_thread_list couldn't determine
403 which was the "main" thread. The latter case shouldn't
404 usually happen, but we're dealing with input here, which can
405 always be broken in different ways. */
406 struct thread_info *thread = first_thread_of_process (-1);
407
408 if (thread == NULL)
409 {
410 inferior_appeared (current_inferior (), CORELOW_PID);
411 inferior_ptid = pid_to_ptid (CORELOW_PID);
412 add_thread_silent (inferior_ptid);
413 }
414 else
415 switch_to_thread (thread->ptid);
416 }
417
418 post_create_inferior (&core_ops, from_tty);
419
420 /* Now go through the target stack looking for threads since there
421 may be a thread_stratum target loaded on top of target core by
422 now. The layer above should claim threads found in the BFD
423 sections. */
424 target_find_new_threads ();
425
426 p = bfd_core_file_failing_command (core_bfd);
427 if (p)
428 printf_filtered (_("Core was generated by `%s'.\n"), p);
429
430 siggy = bfd_core_file_failing_signal (core_bfd);
431 if (siggy > 0)
432 /* NOTE: target_signal_from_host() converts a target signal value
433 into gdb's internal signal value. Unfortunately gdb's internal
434 value is called ``target_signal'' and this function got the
435 name ..._from_host(). */
436 printf_filtered (_("Program terminated with signal %d, %s.\n"), siggy,
437 target_signal_to_string (
438 (core_gdbarch != NULL) ?
439 gdbarch_target_signal_from_host (core_gdbarch, siggy)
440 : siggy));
441
442 /* Fetch all registers from core file. */
443 target_fetch_registers (get_current_regcache (), -1);
444
445 /* Now, set up the frame cache, and print the top of stack. */
446 reinit_frame_cache ();
447 print_stack_frame (get_selected_frame (NULL), 1, SRC_AND_LOC);
448 }
449
450 static void
451 core_detach (struct target_ops *ops, char *args, int from_tty)
452 {
453 if (args)
454 error (_("Too many arguments"));
455 unpush_target (ops);
456 reinit_frame_cache ();
457 if (from_tty)
458 printf_filtered (_("No core file now.\n"));
459 }
460
461 #ifdef DEPRECATED_IBM6000_TARGET
462
463 /* Resize the core memory's section table, by NUM_ADDED. Returns a
464 pointer into the first new slot. This will not be necessary when
465 the rs6000 target is converted to use the standard solib
466 framework. */
467
468 struct target_section *
469 deprecated_core_resize_section_table (int num_added)
470 {
471 int old_count;
472
473 old_count = resize_section_table (core_data, num_added);
474 return core_data->sections + old_count;
475 }
476
477 #endif
478
479 /* Try to retrieve registers from a section in core_bfd, and supply
480 them to core_vec->core_read_registers, as the register set numbered
481 WHICH.
482
483 If inferior_ptid's lwp member is zero, do the single-threaded
484 thing: look for a section named NAME. If inferior_ptid's lwp
485 member is non-zero, do the multi-threaded thing: look for a section
486 named "NAME/LWP", where LWP is the shortest ASCII decimal
487 representation of inferior_ptid's lwp member.
488
489 HUMAN_NAME is a human-readable name for the kind of registers the
490 NAME section contains, for use in error messages.
491
492 If REQUIRED is non-zero, print an error if the core file doesn't
493 have a section by the appropriate name. Otherwise, just do nothing. */
494
495 static void
496 get_core_register_section (struct regcache *regcache,
497 const char *name,
498 int which,
499 const char *human_name,
500 int required)
501 {
502 static char *section_name = NULL;
503 struct bfd_section *section;
504 bfd_size_type size;
505 char *contents;
506
507 xfree (section_name);
508
509 if (ptid_get_lwp (inferior_ptid))
510 section_name = xstrprintf ("%s/%ld", name, ptid_get_lwp (inferior_ptid));
511 else
512 section_name = xstrdup (name);
513
514 section = bfd_get_section_by_name (core_bfd, section_name);
515 if (! section)
516 {
517 if (required)
518 warning (_("Couldn't find %s registers in core file."), human_name);
519 return;
520 }
521
522 size = bfd_section_size (core_bfd, section);
523 contents = alloca (size);
524 if (! bfd_get_section_contents (core_bfd, section, contents,
525 (file_ptr) 0, size))
526 {
527 warning (_("Couldn't read %s registers from `%s' section in core file."),
528 human_name, name);
529 return;
530 }
531
532 if (core_gdbarch && gdbarch_regset_from_core_section_p (core_gdbarch))
533 {
534 const struct regset *regset;
535
536 regset = gdbarch_regset_from_core_section (core_gdbarch, name, size);
537 if (regset == NULL)
538 {
539 if (required)
540 warning (_("Couldn't recognize %s registers in core file."),
541 human_name);
542 return;
543 }
544
545 regset->supply_regset (regset, regcache, -1, contents, size);
546 return;
547 }
548
549 gdb_assert (core_vec);
550 core_vec->core_read_registers (regcache, contents, size, which,
551 ((CORE_ADDR)
552 bfd_section_vma (core_bfd, section)));
553 }
554
555
556 /* Get the registers out of a core file. This is the machine-
557 independent part. Fetch_core_registers is the machine-dependent
558 part, typically implemented in the xm-file for each architecture. */
559
560 /* We just get all the registers, so we don't use regno. */
561
562 static void
563 get_core_registers (struct target_ops *ops,
564 struct regcache *regcache, int regno)
565 {
566 struct core_regset_section *sect_list;
567 int i;
568
569 if (!(core_gdbarch && gdbarch_regset_from_core_section_p (core_gdbarch))
570 && (core_vec == NULL || core_vec->core_read_registers == NULL))
571 {
572 fprintf_filtered (gdb_stderr,
573 "Can't fetch registers from this type of core file\n");
574 return;
575 }
576
577 sect_list = gdbarch_core_regset_sections (get_regcache_arch (regcache));
578 if (sect_list)
579 while (sect_list->sect_name != NULL)
580 {
581 if (strcmp (sect_list->sect_name, ".reg") == 0)
582 get_core_register_section (regcache, sect_list->sect_name,
583 0, sect_list->human_name, 1);
584 else if (strcmp (sect_list->sect_name, ".reg2") == 0)
585 get_core_register_section (regcache, sect_list->sect_name,
586 2, sect_list->human_name, 0);
587 else
588 get_core_register_section (regcache, sect_list->sect_name,
589 3, sect_list->human_name, 0);
590
591 sect_list++;
592 }
593
594 else
595 {
596 get_core_register_section (regcache,
597 ".reg", 0, "general-purpose", 1);
598 get_core_register_section (regcache,
599 ".reg2", 2, "floating-point", 0);
600 }
601
602 /* Supply dummy value for all registers not found in the core. */
603 for (i = 0; i < gdbarch_num_regs (get_regcache_arch (regcache)); i++)
604 if (!regcache_valid_p (regcache, i))
605 regcache_raw_supply (regcache, i, NULL);
606 }
607
608 static void
609 core_files_info (struct target_ops *t)
610 {
611 print_section_info (core_data, core_bfd);
612 }
613 \f
614 struct spuid_list
615 {
616 gdb_byte *buf;
617 ULONGEST offset;
618 LONGEST len;
619 ULONGEST pos;
620 ULONGEST written;
621 };
622
623 static void
624 add_to_spuid_list (bfd *abfd, asection *asect, void *list_p)
625 {
626 struct spuid_list *list = list_p;
627 enum bfd_endian byte_order
628 = bfd_big_endian (abfd)? BFD_ENDIAN_BIG : BFD_ENDIAN_LITTLE;
629 int fd, pos = 0;
630
631 sscanf (bfd_section_name (abfd, asect), "SPU/%d/regs%n", &fd, &pos);
632 if (pos == 0)
633 return;
634
635 if (list->pos >= list->offset && list->pos + 4 <= list->offset + list->len)
636 {
637 store_unsigned_integer (list->buf + list->pos - list->offset,
638 4, byte_order, fd);
639 list->written += 4;
640 }
641 list->pos += 4;
642 }
643
644 static LONGEST
645 core_xfer_partial (struct target_ops *ops, enum target_object object,
646 const char *annex, gdb_byte *readbuf,
647 const gdb_byte *writebuf, ULONGEST offset, LONGEST len)
648 {
649 switch (object)
650 {
651 case TARGET_OBJECT_MEMORY:
652 return section_table_xfer_memory_partial (readbuf, writebuf,
653 offset, len,
654 core_data->sections,
655 core_data->sections_end,
656 NULL);
657
658 case TARGET_OBJECT_AUXV:
659 if (readbuf)
660 {
661 /* When the aux vector is stored in core file, BFD
662 represents this with a fake section called ".auxv". */
663
664 struct bfd_section *section;
665 bfd_size_type size;
666
667 section = bfd_get_section_by_name (core_bfd, ".auxv");
668 if (section == NULL)
669 return -1;
670
671 size = bfd_section_size (core_bfd, section);
672 if (offset >= size)
673 return 0;
674 size -= offset;
675 if (size > len)
676 size = len;
677 if (size > 0
678 && !bfd_get_section_contents (core_bfd, section, readbuf,
679 (file_ptr) offset, size))
680 {
681 warning (_("Couldn't read NT_AUXV note in core file."));
682 return -1;
683 }
684
685 return size;
686 }
687 return -1;
688
689 case TARGET_OBJECT_WCOOKIE:
690 if (readbuf)
691 {
692 /* When the StackGhost cookie is stored in core file, BFD
693 represents this with a fake section called ".wcookie". */
694
695 struct bfd_section *section;
696 bfd_size_type size;
697
698 section = bfd_get_section_by_name (core_bfd, ".wcookie");
699 if (section == NULL)
700 return -1;
701
702 size = bfd_section_size (core_bfd, section);
703 if (offset >= size)
704 return 0;
705 size -= offset;
706 if (size > len)
707 size = len;
708 if (size > 0
709 && !bfd_get_section_contents (core_bfd, section, readbuf,
710 (file_ptr) offset, size))
711 {
712 warning (_("Couldn't read StackGhost cookie in core file."));
713 return -1;
714 }
715
716 return size;
717 }
718 return -1;
719
720 case TARGET_OBJECT_LIBRARIES:
721 if (core_gdbarch
722 && gdbarch_core_xfer_shared_libraries_p (core_gdbarch))
723 {
724 if (writebuf)
725 return -1;
726 return
727 gdbarch_core_xfer_shared_libraries (core_gdbarch,
728 readbuf, offset, len);
729 }
730 /* FALL THROUGH */
731
732 case TARGET_OBJECT_SPU:
733 if (readbuf && annex)
734 {
735 /* When the SPU contexts are stored in a core file, BFD
736 represents this with a fake section called "SPU/<annex>". */
737
738 struct bfd_section *section;
739 bfd_size_type size;
740 char sectionstr[100];
741
742 xsnprintf (sectionstr, sizeof sectionstr, "SPU/%s", annex);
743
744 section = bfd_get_section_by_name (core_bfd, sectionstr);
745 if (section == NULL)
746 return -1;
747
748 size = bfd_section_size (core_bfd, section);
749 if (offset >= size)
750 return 0;
751 size -= offset;
752 if (size > len)
753 size = len;
754 if (size > 0
755 && !bfd_get_section_contents (core_bfd, section, readbuf,
756 (file_ptr) offset, size))
757 {
758 warning (_("Couldn't read SPU section in core file."));
759 return -1;
760 }
761
762 return size;
763 }
764 else if (readbuf)
765 {
766 /* NULL annex requests list of all present spuids. */
767 struct spuid_list list;
768
769 list.buf = readbuf;
770 list.offset = offset;
771 list.len = len;
772 list.pos = 0;
773 list.written = 0;
774 bfd_map_over_sections (core_bfd, add_to_spuid_list, &list);
775 return list.written;
776 }
777 return -1;
778
779 default:
780 if (ops->beneath != NULL)
781 return ops->beneath->to_xfer_partial (ops->beneath, object, annex,
782 readbuf, writebuf, offset, len);
783 return -1;
784 }
785 }
786
787 \f
788 /* If mourn is being called in all the right places, this could be say
789 `gdb internal error' (since generic_mourn calls breakpoint_init_inferior). */
790
791 static int
792 ignore (struct gdbarch *gdbarch, struct bp_target_info *bp_tgt)
793 {
794 return 0;
795 }
796
797
798 /* Okay, let's be honest: threads gleaned from a core file aren't
799 exactly lively, are they? On the other hand, if we don't claim
800 that each & every one is alive, then we don't get any of them
801 to appear in an "info thread" command, which is quite a useful
802 behaviour.
803 */
804 static int
805 core_thread_alive (struct target_ops *ops, ptid_t ptid)
806 {
807 return 1;
808 }
809
810 /* Ask the current architecture what it knows about this core file.
811 That will be used, in turn, to pick a better architecture. This
812 wrapper could be avoided if targets got a chance to specialize
813 core_ops. */
814
815 static const struct target_desc *
816 core_read_description (struct target_ops *target)
817 {
818 if (core_gdbarch && gdbarch_core_read_description_p (core_gdbarch))
819 return gdbarch_core_read_description (core_gdbarch, target, core_bfd);
820
821 return NULL;
822 }
823
824 static char *
825 core_pid_to_str (struct target_ops *ops, ptid_t ptid)
826 {
827 static char buf[64];
828 int pid;
829
830 /* The preferred way is to have a gdbarch/OS specific
831 implementation. */
832 if (core_gdbarch
833 && gdbarch_core_pid_to_str_p (core_gdbarch))
834 return gdbarch_core_pid_to_str (core_gdbarch, ptid);
835
836 /* Otherwise, if we don't have one, we'll just fallback to
837 "process", with normal_pid_to_str. */
838
839 /* Try the LWPID field first. */
840 pid = ptid_get_lwp (ptid);
841 if (pid != 0)
842 return normal_pid_to_str (pid_to_ptid (pid));
843
844 /* Otherwise, this isn't a "threaded" core -- use the PID field, but
845 only if it isn't a fake PID. */
846 if (!core_has_fake_pid)
847 return normal_pid_to_str (ptid);
848
849 /* No luck. We simply don't have a valid PID to print. */
850 xsnprintf (buf, sizeof buf, "<main task>");
851 return buf;
852 }
853
854 static int
855 core_has_memory (struct target_ops *ops)
856 {
857 return (core_bfd != NULL);
858 }
859
860 static int
861 core_has_stack (struct target_ops *ops)
862 {
863 return (core_bfd != NULL);
864 }
865
866 static int
867 core_has_registers (struct target_ops *ops)
868 {
869 return (core_bfd != NULL);
870 }
871
872 /* Fill in core_ops with its defined operations and properties. */
873
874 static void
875 init_core_ops (void)
876 {
877 core_ops.to_shortname = "core";
878 core_ops.to_longname = "Local core dump file";
879 core_ops.to_doc =
880 "Use a core file as a target. Specify the filename of the core file.";
881 core_ops.to_open = core_open;
882 core_ops.to_close = core_close;
883 core_ops.to_attach = find_default_attach;
884 core_ops.to_detach = core_detach;
885 core_ops.to_fetch_registers = get_core_registers;
886 core_ops.to_xfer_partial = core_xfer_partial;
887 core_ops.to_files_info = core_files_info;
888 core_ops.to_insert_breakpoint = ignore;
889 core_ops.to_remove_breakpoint = ignore;
890 core_ops.to_create_inferior = find_default_create_inferior;
891 core_ops.to_thread_alive = core_thread_alive;
892 core_ops.to_read_description = core_read_description;
893 core_ops.to_pid_to_str = core_pid_to_str;
894 core_ops.to_stratum = process_stratum;
895 core_ops.to_has_memory = core_has_memory;
896 core_ops.to_has_stack = core_has_stack;
897 core_ops.to_has_registers = core_has_registers;
898 core_ops.to_magic = OPS_MAGIC;
899
900 if (core_target)
901 internal_error (__FILE__, __LINE__,
902 _("init_core_ops: core target already exists (\"%s\")."),
903 core_target->to_longname);
904 core_target = &core_ops;
905 }
906
907 void
908 _initialize_corelow (void)
909 {
910 init_core_ops ();
911
912 add_target (&core_ops);
913 }