1 /* Core dump and executable file functions below target vector, for GDB.
3 Copyright (C) 1986-2014 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21 #include "arch-utils.h"
26 #ifdef HAVE_SYS_FILE_H
27 #include <sys/file.h> /* needed for F_OK and friends */
29 #include "frame.h" /* required by inferior.h */
36 #include "gdbthread.h"
41 #include "readline/readline.h"
42 #include "gdb_assert.h"
43 #include "exceptions.h"
45 #include "filenames.h"
46 #include "progspace.h"
49 #include "completer.h"
50 #include "filestuff.h"
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. */
60 static struct core_fns *core_file_fns = NULL;
62 /* The core_fns for a core file handler that is prepared to read the
63 core file currently open on core_bfd. */
65 static struct core_fns *core_vec = NULL;
67 /* FIXME: kettenis/20031023: Eventually this variable should
70 static struct gdbarch *core_gdbarch = NULL;
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;
80 static void core_files_info (struct target_ops *);
82 static struct core_fns *sniff_core_bfd (bfd *);
84 static int gdb_check_format (bfd *);
86 static void core_open (char *, int);
88 static void core_close (void);
90 static void core_close_cleanup (void *ignore);
92 static void add_to_thread_list (bfd *, asection *, void *);
94 static void init_core_ops (void);
96 void _initialize_corelow (void);
98 static struct target_ops core_ops;
100 /* An arbitrary identifier for the core inferior. */
101 #define CORELOW_PID 1
103 /* Link a new core_fns into the global core_file_fns list. Called on
104 gdb startup by the _initialize routine in each core file register
105 reader, to register information about each format the reader is
106 prepared to handle. */
109 deprecated_add_core_fns (struct core_fns *cf)
111 cf->next = core_file_fns;
115 /* The default function that core file handlers can use to examine a
116 core file BFD and decide whether or not to accept the job of
117 reading the core file. */
120 default_core_sniffer (struct core_fns *our_fns, bfd *abfd)
124 result = (bfd_get_flavour (abfd) == our_fns -> core_flavour);
128 /* Walk through the list of core functions to find a set that can
129 handle the core file open on ABFD. Returns pointer to set that is
132 static struct core_fns *
133 sniff_core_bfd (bfd *abfd)
136 struct core_fns *yummy = NULL;
139 /* Don't sniff if we have support for register sets in
141 if (core_gdbarch && gdbarch_regset_from_core_section_p (core_gdbarch))
144 for (cf = core_file_fns; cf != NULL; cf = cf->next)
146 if (cf->core_sniffer (cf, abfd))
154 warning (_("\"%s\": ambiguous core format, %d handlers match"),
155 bfd_get_filename (abfd), matches);
157 else if (matches == 0)
158 error (_("\"%s\": no core file handler recognizes format"),
159 bfd_get_filename (abfd));
164 /* The default is to reject every core file format we see. Either
165 BFD has to recognize it, or we have to provide a function in the
166 core file handler that recognizes it. */
169 default_check_format (bfd *abfd)
174 /* Attempt to recognize core file formats that BFD rejects. */
177 gdb_check_format (bfd *abfd)
181 for (cf = core_file_fns; cf != NULL; cf = cf->next)
183 if (cf->check_format (abfd))
191 /* Discard all vestiges of any previous core file and mark data and
192 stack spaces as empty. */
199 int pid = ptid_get_pid (inferior_ptid);
200 inferior_ptid = null_ptid; /* Avoid confusion from thread
203 exit_inferior_silent (pid);
205 /* Clear out solib state while the bfd is still open. See
206 comments in clear_solib in solib.c. */
211 xfree (core_data->sections);
216 gdb_bfd_unref (core_bfd);
224 core_close_cleanup (void *ignore)
229 /* Look for sections whose names start with `.reg/' so that we can
230 extract the list of threads in a core file. */
233 add_to_thread_list (bfd *abfd, asection *asect, void *reg_sect_arg)
238 asection *reg_sect = (asection *) reg_sect_arg;
240 struct inferior *inf;
242 if (strncmp (bfd_section_name (abfd, asect), ".reg/", 5) != 0)
245 core_tid = atoi (bfd_section_name (abfd, asect) + 5);
247 pid = bfd_core_file_pid (core_bfd);
256 inf = current_inferior ();
259 inferior_appeared (inf, pid);
260 inf->fake_pid_p = fake_pid_p;
263 ptid = ptid_build (pid, lwpid, 0);
267 /* Warning, Will Robinson, looking at BFD private data! */
270 && asect->filepos == reg_sect->filepos) /* Did we find .reg? */
271 inferior_ptid = ptid; /* Yes, make it current. */
274 /* This routine opens and sets up the core file bfd. */
277 core_open (char *filename, int from_tty)
281 struct cleanup *old_chain;
286 volatile struct gdb_exception except;
288 target_preopen (from_tty);
292 error (_("No core file specified. (Use `detach' "
293 "to stop debugging a core file.)"));
295 error (_("No core file specified."));
298 filename = tilde_expand (filename);
299 if (!IS_ABSOLUTE_PATH (filename))
301 temp = concat (current_directory, "/",
302 filename, (char *) NULL);
307 old_chain = make_cleanup (xfree, filename);
309 flags = O_BINARY | O_LARGEFILE;
314 scratch_chan = gdb_open_cloexec (filename, flags, 0);
315 if (scratch_chan < 0)
316 perror_with_name (filename);
318 temp_bfd = gdb_bfd_fopen (filename, gnutarget,
319 write_files ? FOPEN_RUB : FOPEN_RB,
321 if (temp_bfd == NULL)
322 perror_with_name (filename);
324 if (!bfd_check_format (temp_bfd, bfd_core)
325 && !gdb_check_format (temp_bfd))
327 /* Do it after the err msg */
328 /* FIXME: should be checking for errors from bfd_close (for one
329 thing, on error it does not free all the storage associated
331 make_cleanup_bfd_unref (temp_bfd);
332 error (_("\"%s\" is not a core dump: %s"),
333 filename, bfd_errmsg (bfd_get_error ()));
336 /* Looks semi-reasonable. Toss the old core file and work on the
339 do_cleanups (old_chain);
340 unpush_target (&core_ops);
342 old_chain = make_cleanup (core_close_cleanup, 0 /*ignore*/);
344 core_gdbarch = gdbarch_from_bfd (core_bfd);
346 /* Find a suitable core file handler to munch on core_bfd */
347 core_vec = sniff_core_bfd (core_bfd);
351 core_data = XCNEW (struct target_section_table);
353 /* Find the data section */
354 if (build_section_table (core_bfd,
355 &core_data->sections,
356 &core_data->sections_end))
357 error (_("\"%s\": Can't find sections: %s"),
358 bfd_get_filename (core_bfd), bfd_errmsg (bfd_get_error ()));
360 /* If we have no exec file, try to set the architecture from the
361 core file. We don't do this unconditionally since an exec file
362 typically contains more information that helps us determine the
363 architecture than a core file. */
365 set_gdbarch_from_file (core_bfd);
367 push_target (&core_ops);
368 discard_cleanups (old_chain);
370 /* Do this before acknowledging the inferior, so if
371 post_create_inferior throws (can happen easilly if you're loading
372 a core file with the wrong exec), we aren't left with threads
373 from the previous inferior. */
376 inferior_ptid = null_ptid;
378 /* Need to flush the register cache (and the frame cache) from a
379 previous debug session. If inferior_ptid ends up the same as the
380 last debug session --- e.g., b foo; run; gcore core1; step; gcore
381 core2; core core1; core core2 --- then there's potential for
382 get_current_regcache to return the cached regcache of the
383 previous session, and the frame cache being stale. */
384 registers_changed ();
386 /* Build up thread list from BFD sections, and possibly set the
387 current thread to the .reg/NN section matching the .reg
389 bfd_map_over_sections (core_bfd, add_to_thread_list,
390 bfd_get_section_by_name (core_bfd, ".reg"));
392 if (ptid_equal (inferior_ptid, null_ptid))
394 /* Either we found no .reg/NN section, and hence we have a
395 non-threaded core (single-threaded, from gdb's perspective),
396 or for some reason add_to_thread_list couldn't determine
397 which was the "main" thread. The latter case shouldn't
398 usually happen, but we're dealing with input here, which can
399 always be broken in different ways. */
400 struct thread_info *thread = first_thread_of_process (-1);
404 inferior_appeared (current_inferior (), CORELOW_PID);
405 inferior_ptid = pid_to_ptid (CORELOW_PID);
406 add_thread_silent (inferior_ptid);
409 switch_to_thread (thread->ptid);
412 post_create_inferior (&core_ops, from_tty);
414 /* Now go through the target stack looking for threads since there
415 may be a thread_stratum target loaded on top of target core by
416 now. The layer above should claim threads found in the BFD
418 TRY_CATCH (except, RETURN_MASK_ERROR)
420 target_find_new_threads ();
423 if (except.reason < 0)
424 exception_print (gdb_stderr, except);
426 p = bfd_core_file_failing_command (core_bfd);
428 printf_filtered (_("Core was generated by `%s'.\n"), p);
430 /* Clearing any previous state of convenience variables. */
431 clear_exit_convenience_vars ();
433 siggy = bfd_core_file_failing_signal (core_bfd);
436 /* If we don't have a CORE_GDBARCH to work with, assume a native
437 core (map gdb_signal from host signals). If we do have
438 CORE_GDBARCH to work with, but no gdb_signal_from_target
439 implementation for that gdbarch, as a fallback measure,
440 assume the host signal mapping. It'll be correct for native
441 cores, but most likely incorrect for cross-cores. */
442 enum gdb_signal sig = (core_gdbarch != NULL
443 && gdbarch_gdb_signal_from_target_p (core_gdbarch)
444 ? gdbarch_gdb_signal_from_target (core_gdbarch,
446 : gdb_signal_from_host (siggy));
448 printf_filtered (_("Program terminated with signal %s, %s.\n"),
449 gdb_signal_to_name (sig), gdb_signal_to_string (sig));
451 /* Set the value of the internal variable $_exitsignal,
452 which holds the signal uncaught by the inferior. */
453 set_internalvar_integer (lookup_internalvar ("_exitsignal"),
457 /* Fetch all registers from core file. */
458 target_fetch_registers (get_current_regcache (), -1);
460 /* Now, set up the frame cache, and print the top of stack. */
461 reinit_frame_cache ();
462 print_stack_frame (get_selected_frame (NULL), 1, SRC_AND_LOC, 1);
466 core_detach (struct target_ops *ops, const char *args, int from_tty)
469 error (_("Too many arguments"));
471 reinit_frame_cache ();
473 printf_filtered (_("No core file now.\n"));
476 /* Try to retrieve registers from a section in core_bfd, and supply
477 them to core_vec->core_read_registers, as the register set numbered
480 If inferior_ptid's lwp member is zero, do the single-threaded
481 thing: look for a section named NAME. If inferior_ptid's lwp
482 member is non-zero, do the multi-threaded thing: look for a section
483 named "NAME/LWP", where LWP is the shortest ASCII decimal
484 representation of inferior_ptid's lwp member.
486 HUMAN_NAME is a human-readable name for the kind of registers the
487 NAME section contains, for use in error messages.
489 If REQUIRED is non-zero, print an error if the core file doesn't
490 have a section by the appropriate name. Otherwise, just do
494 get_core_register_section (struct regcache *regcache,
497 const char *human_name,
500 static char *section_name = NULL;
501 struct bfd_section *section;
505 xfree (section_name);
507 if (ptid_get_lwp (inferior_ptid))
508 section_name = xstrprintf ("%s/%ld", name,
509 ptid_get_lwp (inferior_ptid));
511 section_name = xstrdup (name);
513 section = bfd_get_section_by_name (core_bfd, section_name);
517 warning (_("Couldn't find %s registers in core file."),
522 size = bfd_section_size (core_bfd, section);
523 contents = alloca (size);
524 if (! bfd_get_section_contents (core_bfd, section, contents,
527 warning (_("Couldn't read %s registers from `%s' section in core file."),
532 if (core_gdbarch && gdbarch_regset_from_core_section_p (core_gdbarch))
534 const struct regset *regset;
536 regset = gdbarch_regset_from_core_section (core_gdbarch,
541 warning (_("Couldn't recognize %s registers in core file."),
546 regset->supply_regset (regset, regcache, -1, contents, size);
550 gdb_assert (core_vec);
551 core_vec->core_read_registers (regcache, contents, size, which,
553 bfd_section_vma (core_bfd, section)));
557 /* Get the registers out of a core file. This is the machine-
558 independent part. Fetch_core_registers is the machine-dependent
559 part, typically implemented in the xm-file for each
562 /* We just get all the registers, so we don't use regno. */
565 get_core_registers (struct target_ops *ops,
566 struct regcache *regcache, int regno)
568 struct core_regset_section *sect_list;
571 if (!(core_gdbarch && gdbarch_regset_from_core_section_p (core_gdbarch))
572 && (core_vec == NULL || core_vec->core_read_registers == NULL))
574 fprintf_filtered (gdb_stderr,
575 "Can't fetch registers from this type of core file\n");
579 sect_list = gdbarch_core_regset_sections (get_regcache_arch (regcache));
581 while (sect_list->sect_name != NULL)
583 if (strcmp (sect_list->sect_name, ".reg") == 0)
584 get_core_register_section (regcache, sect_list->sect_name,
585 0, sect_list->human_name, 1);
586 else if (strcmp (sect_list->sect_name, ".reg2") == 0)
587 get_core_register_section (regcache, sect_list->sect_name,
588 2, sect_list->human_name, 0);
590 get_core_register_section (regcache, sect_list->sect_name,
591 3, sect_list->human_name, 0);
598 get_core_register_section (regcache,
599 ".reg", 0, "general-purpose", 1);
600 get_core_register_section (regcache,
601 ".reg2", 2, "floating-point", 0);
604 /* Mark all registers not found in the core as unavailable. */
605 for (i = 0; i < gdbarch_num_regs (get_regcache_arch (regcache)); i++)
606 if (regcache_register_status (regcache, i) == REG_UNKNOWN)
607 regcache_raw_supply (regcache, i, NULL);
611 core_files_info (struct target_ops *t)
613 print_section_info (core_data, core_bfd);
626 add_to_spuid_list (bfd *abfd, asection *asect, void *list_p)
628 struct spuid_list *list = list_p;
629 enum bfd_endian byte_order
630 = bfd_big_endian (abfd) ? BFD_ENDIAN_BIG : BFD_ENDIAN_LITTLE;
633 sscanf (bfd_section_name (abfd, asect), "SPU/%d/regs%n", &fd, &pos);
637 if (list->pos >= list->offset && list->pos + 4 <= list->offset + list->len)
639 store_unsigned_integer (list->buf + list->pos - list->offset,
646 /* Read siginfo data from the core, if possible. Returns -1 on
647 failure. Otherwise, returns the number of bytes read. ABFD is the
648 core file's BFD; READBUF, OFFSET, and LEN are all as specified by
649 the to_xfer_partial interface. */
652 get_core_siginfo (bfd *abfd, gdb_byte *readbuf, ULONGEST offset, LONGEST len)
656 const char *name = ".note.linuxcore.siginfo";
658 if (ptid_get_lwp (inferior_ptid))
659 section_name = xstrprintf ("%s/%ld", name,
660 ptid_get_lwp (inferior_ptid));
662 section_name = xstrdup (name);
664 section = bfd_get_section_by_name (abfd, section_name);
665 xfree (section_name);
669 if (!bfd_get_section_contents (abfd, section, readbuf, offset, len))
676 core_xfer_partial (struct target_ops *ops, enum target_object object,
677 const char *annex, gdb_byte *readbuf,
678 const gdb_byte *writebuf, ULONGEST offset,
683 case TARGET_OBJECT_MEMORY:
684 return section_table_xfer_memory_partial (readbuf, writebuf,
687 core_data->sections_end,
690 case TARGET_OBJECT_AUXV:
693 /* When the aux vector is stored in core file, BFD
694 represents this with a fake section called ".auxv". */
696 struct bfd_section *section;
699 section = bfd_get_section_by_name (core_bfd, ".auxv");
703 size = bfd_section_size (core_bfd, section);
710 && !bfd_get_section_contents (core_bfd, section, readbuf,
711 (file_ptr) offset, size))
713 warning (_("Couldn't read NT_AUXV note in core file."));
721 case TARGET_OBJECT_WCOOKIE:
724 /* When the StackGhost cookie is stored in core file, BFD
725 represents this with a fake section called
728 struct bfd_section *section;
731 section = bfd_get_section_by_name (core_bfd, ".wcookie");
735 size = bfd_section_size (core_bfd, section);
742 && !bfd_get_section_contents (core_bfd, section, readbuf,
743 (file_ptr) offset, size))
745 warning (_("Couldn't read StackGhost cookie in core file."));
753 case TARGET_OBJECT_LIBRARIES:
755 && gdbarch_core_xfer_shared_libraries_p (core_gdbarch))
760 gdbarch_core_xfer_shared_libraries (core_gdbarch,
761 readbuf, offset, len);
765 case TARGET_OBJECT_LIBRARIES_AIX:
767 && gdbarch_core_xfer_shared_libraries_aix_p (core_gdbarch))
772 gdbarch_core_xfer_shared_libraries_aix (core_gdbarch,
773 readbuf, offset, len);
777 case TARGET_OBJECT_SPU:
778 if (readbuf && annex)
780 /* When the SPU contexts are stored in a core file, BFD
781 represents this with a fake section called
784 struct bfd_section *section;
786 char sectionstr[100];
788 xsnprintf (sectionstr, sizeof sectionstr, "SPU/%s", annex);
790 section = bfd_get_section_by_name (core_bfd, sectionstr);
794 size = bfd_section_size (core_bfd, section);
801 && !bfd_get_section_contents (core_bfd, section, readbuf,
802 (file_ptr) offset, size))
804 warning (_("Couldn't read SPU section in core file."));
812 /* NULL annex requests list of all present spuids. */
813 struct spuid_list list;
816 list.offset = offset;
820 bfd_map_over_sections (core_bfd, add_to_spuid_list, &list);
825 case TARGET_OBJECT_SIGNAL_INFO:
827 return get_core_siginfo (core_bfd, readbuf, offset, len);
831 if (ops->beneath != NULL)
832 return ops->beneath->to_xfer_partial (ops->beneath, object,
834 writebuf, offset, len);
840 /* If mourn is being called in all the right places, this could be say
841 `gdb internal error' (since generic_mourn calls
842 breakpoint_init_inferior). */
845 ignore (struct target_ops *ops, struct gdbarch *gdbarch,
846 struct bp_target_info *bp_tgt)
852 /* Okay, let's be honest: threads gleaned from a core file aren't
853 exactly lively, are they? On the other hand, if we don't claim
854 that each & every one is alive, then we don't get any of them
855 to appear in an "info thread" command, which is quite a useful
859 core_thread_alive (struct target_ops *ops, ptid_t ptid)
864 /* Ask the current architecture what it knows about this core file.
865 That will be used, in turn, to pick a better architecture. This
866 wrapper could be avoided if targets got a chance to specialize
869 static const struct target_desc *
870 core_read_description (struct target_ops *target)
872 if (core_gdbarch && gdbarch_core_read_description_p (core_gdbarch))
873 return gdbarch_core_read_description (core_gdbarch,
880 core_pid_to_str (struct target_ops *ops, ptid_t ptid)
883 struct inferior *inf;
886 /* The preferred way is to have a gdbarch/OS specific
889 && gdbarch_core_pid_to_str_p (core_gdbarch))
890 return gdbarch_core_pid_to_str (core_gdbarch, ptid);
892 /* Otherwise, if we don't have one, we'll just fallback to
893 "process", with normal_pid_to_str. */
895 /* Try the LWPID field first. */
896 pid = ptid_get_lwp (ptid);
898 return normal_pid_to_str (pid_to_ptid (pid));
900 /* Otherwise, this isn't a "threaded" core -- use the PID field, but
901 only if it isn't a fake PID. */
902 inf = find_inferior_pid (ptid_get_pid (ptid));
903 if (inf != NULL && !inf->fake_pid_p)
904 return normal_pid_to_str (ptid);
906 /* No luck. We simply don't have a valid PID to print. */
907 xsnprintf (buf, sizeof buf, "<main task>");
912 core_has_memory (struct target_ops *ops)
914 return (core_bfd != NULL);
918 core_has_stack (struct target_ops *ops)
920 return (core_bfd != NULL);
924 core_has_registers (struct target_ops *ops)
926 return (core_bfd != NULL);
929 /* Implement the to_info_proc method. */
932 core_info_proc (struct target_ops *ops, char *args, enum info_proc_what request)
934 struct gdbarch *gdbarch = get_current_arch ();
936 /* Since this is the core file target, call the 'core_info_proc'
937 method on gdbarch, not 'info_proc'. */
938 if (gdbarch_core_info_proc_p (gdbarch))
939 gdbarch_core_info_proc (gdbarch, args, request);
942 /* Fill in core_ops with its defined operations and properties. */
947 core_ops.to_shortname = "core";
948 core_ops.to_longname = "Local core dump file";
950 "Use a core file as a target. Specify the filename of the core file.";
951 core_ops.to_open = core_open;
952 core_ops.to_close = core_close;
953 core_ops.to_attach = find_default_attach;
954 core_ops.to_detach = core_detach;
955 core_ops.to_fetch_registers = get_core_registers;
956 core_ops.to_xfer_partial = core_xfer_partial;
957 core_ops.to_files_info = core_files_info;
958 core_ops.to_insert_breakpoint = ignore;
959 core_ops.to_remove_breakpoint = ignore;
960 core_ops.to_create_inferior = find_default_create_inferior;
961 core_ops.to_thread_alive = core_thread_alive;
962 core_ops.to_read_description = core_read_description;
963 core_ops.to_pid_to_str = core_pid_to_str;
964 core_ops.to_stratum = process_stratum;
965 core_ops.to_has_memory = core_has_memory;
966 core_ops.to_has_stack = core_has_stack;
967 core_ops.to_has_registers = core_has_registers;
968 core_ops.to_info_proc = core_info_proc;
969 core_ops.to_magic = OPS_MAGIC;
972 internal_error (__FILE__, __LINE__,
973 _("init_core_ops: core target already exists (\"%s\")."),
974 core_target->to_longname);
975 core_target = &core_ops;
979 _initialize_corelow (void)
983 add_target_with_completer (&core_ops, filename_completer);