1 /* Core dump and executable file functions below target vector, for GDB.
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
5 Free Software Foundation, Inc.
7 This file is part of GDB.
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.
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.
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/>. */
23 #include "arch-utils.h"
24 #include "gdb_string.h"
28 #ifdef HAVE_SYS_FILE_H
29 #include <sys/file.h> /* needed for F_OK and friends */
31 #include "frame.h" /* required by inferior.h */
38 #include "gdbthread.h"
43 #include "readline/readline.h"
44 #include "gdb_assert.h"
45 #include "exceptions.h"
47 #include "filenames.h"
54 /* List of all available core_fns. On gdb startup, each core file
55 register reader calls deprecated_add_core_fns() to register
56 information on each core format it is prepared to read. */
58 static struct core_fns *core_file_fns = NULL;
60 /* The core_fns for a core file handler that is prepared to read the core
61 file currently open on core_bfd. */
63 static struct core_fns *core_vec = NULL;
65 /* FIXME: kettenis/20031023: Eventually this variable should
68 struct gdbarch *core_gdbarch = NULL;
70 static void core_files_info (struct target_ops *);
72 static struct core_fns *sniff_core_bfd (bfd *);
74 static int gdb_check_format (bfd *);
76 static void core_open (char *, int);
78 static void core_detach (struct target_ops *ops, char *, int);
80 static void core_close (int);
82 static void core_close_cleanup (void *ignore);
84 static void add_to_thread_list (bfd *, asection *, void *);
86 static void init_core_ops (void);
88 void _initialize_corelow (void);
90 struct target_ops core_ops;
92 /* An arbitrary identifier for the core inferior. */
95 /* Link a new core_fns into the global core_file_fns list. Called on gdb
96 startup by the _initialize routine in each core file register reader, to
97 register information about each format the the reader is prepared to
101 deprecated_add_core_fns (struct core_fns *cf)
103 cf->next = core_file_fns;
107 /* The default function that core file handlers can use to examine a
108 core file BFD and decide whether or not to accept the job of
109 reading the core file. */
112 default_core_sniffer (struct core_fns *our_fns, bfd *abfd)
116 result = (bfd_get_flavour (abfd) == our_fns -> core_flavour);
120 /* Walk through the list of core functions to find a set that can
121 handle the core file open on ABFD. Default to the first one in the
122 list if nothing matches. Returns pointer to set that is
125 static struct core_fns *
126 sniff_core_bfd (bfd *abfd)
129 struct core_fns *yummy = NULL;
132 /* Don't sniff if we have support for register sets in CORE_GDBARCH. */
133 if (core_gdbarch && gdbarch_regset_from_core_section_p (core_gdbarch))
136 for (cf = core_file_fns; cf != NULL; cf = cf->next)
138 if (cf->core_sniffer (cf, abfd))
146 warning (_("\"%s\": ambiguous core format, %d handlers match"),
147 bfd_get_filename (abfd), matches);
149 else if (matches == 0)
151 warning (_("\"%s\": no core file handler recognizes format, using default"),
152 bfd_get_filename (abfd));
156 yummy = core_file_fns;
161 /* The default is to reject every core file format we see. Either
162 BFD has to recognize it, or we have to provide a function in the
163 core file handler that recognizes it. */
166 default_check_format (bfd *abfd)
171 /* Attempt to recognize core file formats that BFD rejects. */
174 gdb_check_format (bfd *abfd)
178 for (cf = core_file_fns; cf != NULL; cf = cf->next)
180 if (cf->check_format (abfd))
188 /* Discard all vestiges of any previous core file and mark data and stack
192 core_close (int quitting)
198 int pid = ptid_get_pid (inferior_ptid);
199 inferior_ptid = null_ptid; /* Avoid confusion from thread stuff */
200 delete_inferior_silent (pid);
202 /* Clear out solib state while the bfd is still open. See
203 comments in clear_solib in solib.c. */
206 name = bfd_get_filename (core_bfd);
207 if (!bfd_close (core_bfd))
208 warning (_("cannot close \"%s\": %s"),
209 name, bfd_errmsg (bfd_get_error ()));
212 if (core_ops.to_sections)
214 xfree (core_ops.to_sections);
215 core_ops.to_sections = NULL;
216 core_ops.to_sections_end = NULL;
224 core_close_cleanup (void *ignore)
226 core_close (0/*ignored*/);
229 /* Look for sections whose names start with `.reg/' so that we can extract the
230 list of threads in a core file. */
233 add_to_thread_list (bfd *abfd, asection *asect, void *reg_sect_arg)
237 asection *reg_sect = (asection *) reg_sect_arg;
239 if (strncmp (bfd_section_name (abfd, asect), ".reg/", 5) != 0)
242 thread_id = atoi (bfd_section_name (abfd, asect) + 5);
245 && gdbarch_core_reg_section_encodes_pid (core_gdbarch))
247 uint32_t merged_pid = thread_id;
248 ptid = ptid_build (merged_pid & 0xffff,
249 merged_pid >> 16, 0);
252 ptid = ptid_build (ptid_get_pid (inferior_ptid), thread_id, 0);
254 if (ptid_get_lwp (inferior_ptid) == 0)
255 /* The main thread has already been added before getting here, and
256 this is the first time we hear about a thread id. Assume this
257 is the main thread. */
258 thread_change_ptid (inferior_ptid, ptid);
260 /* Nope, really a new thread. */
263 /* Warning, Will Robinson, looking at BFD private data! */
266 && asect->filepos == reg_sect->filepos) /* Did we find .reg? */
267 inferior_ptid = ptid; /* Yes, make it current */
270 /* This routine opens and sets up the core file bfd. */
273 core_open (char *filename, int from_tty)
277 struct cleanup *old_chain;
282 int corelow_pid = CORELOW_PID;
284 target_preopen (from_tty);
288 error (_("No core file specified. (Use `detach' to stop debugging a core file.)"));
290 error (_("No core file specified."));
293 filename = tilde_expand (filename);
294 if (!IS_ABSOLUTE_PATH(filename))
296 temp = concat (current_directory, "/", filename, (char *)NULL);
301 old_chain = make_cleanup (xfree, filename);
303 flags = O_BINARY | O_LARGEFILE;
308 scratch_chan = open (filename, flags, 0);
309 if (scratch_chan < 0)
310 perror_with_name (filename);
312 temp_bfd = bfd_fopen (filename, gnutarget,
313 write_files ? FOPEN_RUB : FOPEN_RB,
315 if (temp_bfd == NULL)
316 perror_with_name (filename);
318 if (!bfd_check_format (temp_bfd, bfd_core) &&
319 !gdb_check_format (temp_bfd))
321 /* Do it after the err msg */
322 /* FIXME: should be checking for errors from bfd_close (for one thing,
323 on error it does not free all the storage associated with the
325 make_cleanup_bfd_close (temp_bfd);
326 error (_("\"%s\" is not a core dump: %s"),
327 filename, bfd_errmsg (bfd_get_error ()));
330 /* Looks semi-reasonable. Toss the old core file and work on the new. */
332 discard_cleanups (old_chain); /* Don't free filename any more */
333 unpush_target (&core_ops);
335 old_chain = make_cleanup (core_close_cleanup, 0 /*ignore*/);
337 /* FIXME: kettenis/20031023: This is very dangerous. The
338 CORE_GDBARCH that results from this call may very well be
339 different from CURRENT_GDBARCH. However, its methods may only
340 work if it is selected as the current architecture, because they
341 rely on swapped data (see gdbarch.c). We should get rid of that
343 core_gdbarch = gdbarch_from_bfd (core_bfd);
345 /* Find a suitable core file handler to munch on core_bfd */
346 core_vec = sniff_core_bfd (core_bfd);
350 /* Find the data section */
351 if (build_section_table (core_bfd, &core_ops.to_sections,
352 &core_ops.to_sections_end))
353 error (_("\"%s\": Can't find sections: %s"),
354 bfd_get_filename (core_bfd), bfd_errmsg (bfd_get_error ()));
356 /* If we have no exec file, try to set the architecture from the
357 core file. We don't do this unconditionally since an exec file
358 typically contains more information that helps us determine the
359 architecture than a core file. */
361 set_gdbarch_from_file (core_bfd);
363 push_target (&core_ops);
364 discard_cleanups (old_chain);
366 add_inferior_silent (corelow_pid);
368 /* Do this before acknowledging the inferior, so if
369 post_create_inferior throws (can happen easilly if you're loading
370 a core file with the wrong exec), we aren't left with threads
371 from the previous inferior. */
374 /* Set INFERIOR_PTID early, so an upper layer can rely on it being
375 set while in the target_find_new_threads call below. */
376 inferior_ptid = pid_to_ptid (corelow_pid);
378 /* Assume ST --- Add a main task. We'll later detect when we go
380 add_thread_silent (inferior_ptid);
382 /* Need to flush the register cache (and the frame cache) from a
383 previous debug session. If inferior_ptid ends up the same as the
384 last debug session --- e.g., b foo; run; gcore core1; step; gcore
385 core2; core core1; core core2 --- then there's potential for
386 get_current_regcache to return the cached regcache of the
387 previous session, and the frame cache being stale. */
388 registers_changed ();
390 /* Build up thread list from BFD sections, and possibly set the
391 current thread to the .reg/NN section matching the .reg
393 bfd_map_over_sections (core_bfd, add_to_thread_list,
394 bfd_get_section_by_name (core_bfd, ".reg"));
396 post_create_inferior (&core_ops, from_tty);
398 /* Now go through the target stack looking for threads since there
399 may be a thread_stratum target loaded on top of target core by
400 now. The layer above should claim threads found in the BFD
402 target_find_new_threads ();
404 p = bfd_core_file_failing_command (core_bfd);
406 printf_filtered (_("Core was generated by `%s'.\n"), p);
408 siggy = bfd_core_file_failing_signal (core_bfd);
410 /* NOTE: target_signal_from_host() converts a target signal value
411 into gdb's internal signal value. Unfortunately gdb's internal
412 value is called ``target_signal'' and this function got the
413 name ..._from_host(). */
414 printf_filtered (_("Program terminated with signal %d, %s.\n"), siggy,
415 target_signal_to_string (
416 gdbarch_target_signal_from_host (core_gdbarch, siggy)));
418 /* Fetch all registers from core file. */
419 target_fetch_registers (get_current_regcache (), -1);
421 /* Now, set up the frame cache, and print the top of stack. */
422 reinit_frame_cache ();
423 print_stack_frame (get_selected_frame (NULL), 1, SRC_AND_LOC);
427 core_detach (struct target_ops *ops, char *args, int from_tty)
430 error (_("Too many arguments"));
432 reinit_frame_cache ();
434 printf_filtered (_("No core file now.\n"));
438 /* Try to retrieve registers from a section in core_bfd, and supply
439 them to core_vec->core_read_registers, as the register set numbered
442 If inferior_ptid's lwp member is zero, do the single-threaded
443 thing: look for a section named NAME. If inferior_ptid's lwp
444 member is non-zero, do the multi-threaded thing: look for a section
445 named "NAME/LWP", where LWP is the shortest ASCII decimal
446 representation of inferior_ptid's lwp member.
448 HUMAN_NAME is a human-readable name for the kind of registers the
449 NAME section contains, for use in error messages.
451 If REQUIRED is non-zero, print an error if the core file doesn't
452 have a section by the appropriate name. Otherwise, just do nothing. */
455 get_core_register_section (struct regcache *regcache,
461 static char *section_name = NULL;
462 struct bfd_section *section;
466 xfree (section_name);
469 && gdbarch_core_reg_section_encodes_pid (core_gdbarch))
473 merged_pid = ptid_get_lwp (inferior_ptid);
474 merged_pid = merged_pid << 16 | ptid_get_pid (inferior_ptid);
476 section_name = xstrprintf ("%s/%s", name, plongest (merged_pid));
478 else if (ptid_get_lwp (inferior_ptid))
479 section_name = xstrprintf ("%s/%ld", name, ptid_get_lwp (inferior_ptid));
481 section_name = xstrdup (name);
483 section = bfd_get_section_by_name (core_bfd, section_name);
487 warning (_("Couldn't find %s registers in core file."), human_name);
491 size = bfd_section_size (core_bfd, section);
492 contents = alloca (size);
493 if (! bfd_get_section_contents (core_bfd, section, contents,
496 warning (_("Couldn't read %s registers from `%s' section in core file."),
501 if (core_gdbarch && gdbarch_regset_from_core_section_p (core_gdbarch))
503 const struct regset *regset;
505 regset = gdbarch_regset_from_core_section (core_gdbarch, name, size);
509 warning (_("Couldn't recognize %s registers in core file."),
514 regset->supply_regset (regset, regcache, -1, contents, size);
518 gdb_assert (core_vec);
519 core_vec->core_read_registers (regcache, contents, size, which,
521 bfd_section_vma (core_bfd, section)));
525 /* Get the registers out of a core file. This is the machine-
526 independent part. Fetch_core_registers is the machine-dependent
527 part, typically implemented in the xm-file for each architecture. */
529 /* We just get all the registers, so we don't use regno. */
532 get_core_registers (struct target_ops *ops,
533 struct regcache *regcache, int regno)
537 if (!(core_gdbarch && gdbarch_regset_from_core_section_p (core_gdbarch))
538 && (core_vec == NULL || core_vec->core_read_registers == NULL))
540 fprintf_filtered (gdb_stderr,
541 "Can't fetch registers from this type of core file\n");
545 get_core_register_section (regcache,
546 ".reg", 0, "general-purpose", 1);
547 get_core_register_section (regcache,
548 ".reg2", 2, "floating-point", 0);
549 get_core_register_section (regcache,
550 ".reg-xfp", 3, "extended floating-point", 0);
551 get_core_register_section (regcache,
552 ".reg-ppc-vmx", 3, "ppc Altivec", 0);
553 get_core_register_section (regcache,
554 ".reg-ppc-vsx", 4, "POWER7 VSX", 0);
556 /* Supply dummy value for all registers not found in the core. */
557 for (i = 0; i < gdbarch_num_regs (get_regcache_arch (regcache)); i++)
558 if (!regcache_valid_p (regcache, i))
559 regcache_raw_supply (regcache, i, NULL);
563 core_files_info (struct target_ops *t)
565 print_section_info (t, core_bfd);
569 core_xfer_partial (struct target_ops *ops, enum target_object object,
570 const char *annex, gdb_byte *readbuf,
571 const gdb_byte *writebuf, ULONGEST offset, LONGEST len)
575 case TARGET_OBJECT_MEMORY:
577 return (*ops->deprecated_xfer_memory) (offset, readbuf,
578 len, 0/*read*/, NULL, ops);
580 return (*ops->deprecated_xfer_memory) (offset, (gdb_byte *) writebuf,
581 len, 1/*write*/, NULL, ops);
584 case TARGET_OBJECT_AUXV:
587 /* When the aux vector is stored in core file, BFD
588 represents this with a fake section called ".auxv". */
590 struct bfd_section *section;
594 section = bfd_get_section_by_name (core_bfd, ".auxv");
598 size = bfd_section_size (core_bfd, section);
605 && !bfd_get_section_contents (core_bfd, section, readbuf,
606 (file_ptr) offset, size))
608 warning (_("Couldn't read NT_AUXV note in core file."));
616 case TARGET_OBJECT_WCOOKIE:
619 /* When the StackGhost cookie is stored in core file, BFD
620 represents this with a fake section called ".wcookie". */
622 struct bfd_section *section;
626 section = bfd_get_section_by_name (core_bfd, ".wcookie");
630 size = bfd_section_size (core_bfd, section);
637 && !bfd_get_section_contents (core_bfd, section, readbuf,
638 (file_ptr) offset, size))
640 warning (_("Couldn't read StackGhost cookie in core file."));
648 case TARGET_OBJECT_LIBRARIES:
650 && gdbarch_core_xfer_shared_libraries_p (core_gdbarch))
655 gdbarch_core_xfer_shared_libraries (core_gdbarch,
656 readbuf, offset, len);
661 if (ops->beneath != NULL)
662 return ops->beneath->to_xfer_partial (ops->beneath, object, annex,
663 readbuf, writebuf, offset, len);
669 /* If mourn is being called in all the right places, this could be say
670 `gdb internal error' (since generic_mourn calls breakpoint_init_inferior). */
673 ignore (struct bp_target_info *bp_tgt)
679 /* Okay, let's be honest: threads gleaned from a core file aren't
680 exactly lively, are they? On the other hand, if we don't claim
681 that each & every one is alive, then we don't get any of them
682 to appear in an "info thread" command, which is quite a useful
686 core_thread_alive (struct target_ops *ops, ptid_t ptid)
691 /* Ask the current architecture what it knows about this core file.
692 That will be used, in turn, to pick a better architecture. This
693 wrapper could be avoided if targets got a chance to specialize
696 static const struct target_desc *
697 core_read_description (struct target_ops *target)
699 if (gdbarch_core_read_description_p (current_gdbarch))
700 return gdbarch_core_read_description (current_gdbarch, target, core_bfd);
706 core_pid_to_str (struct target_ops *ops, ptid_t ptid)
711 && gdbarch_core_pid_to_str_p (core_gdbarch))
713 char *ret = gdbarch_core_pid_to_str (core_gdbarch, ptid);
718 if (ptid_get_lwp (ptid) == 0)
719 xsnprintf (buf, sizeof buf, "<main task>");
721 xsnprintf (buf, sizeof buf, "Thread %ld", ptid_get_lwp (ptid));
726 /* Fill in core_ops with its defined operations and properties. */
731 core_ops.to_shortname = "core";
732 core_ops.to_longname = "Local core dump file";
734 "Use a core file as a target. Specify the filename of the core file.";
735 core_ops.to_open = core_open;
736 core_ops.to_close = core_close;
737 core_ops.to_attach = find_default_attach;
738 core_ops.to_detach = core_detach;
739 core_ops.to_fetch_registers = get_core_registers;
740 core_ops.to_xfer_partial = core_xfer_partial;
741 core_ops.deprecated_xfer_memory = xfer_memory;
742 core_ops.to_files_info = core_files_info;
743 core_ops.to_insert_breakpoint = ignore;
744 core_ops.to_remove_breakpoint = ignore;
745 core_ops.to_create_inferior = find_default_create_inferior;
746 core_ops.to_thread_alive = core_thread_alive;
747 core_ops.to_read_description = core_read_description;
748 core_ops.to_pid_to_str = core_pid_to_str;
749 core_ops.to_stratum = core_stratum;
750 core_ops.to_has_memory = 1;
751 core_ops.to_has_stack = 1;
752 core_ops.to_has_registers = 1;
753 core_ops.to_magic = OPS_MAGIC;
757 _initialize_corelow (void)
761 add_target (&core_ops);