1 /* Work with executable files, for GDB.
3 Copyright (C) 1988-2014 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/>. */
26 #include "filenames.h"
29 #include "completer.h"
33 #include "arch-utils.h"
34 #include "gdbthread.h"
35 #include "progspace.h"
40 #include "readline/readline.h"
48 void (*deprecated_file_changed_hook
) (char *);
50 /* Prototypes for local functions */
52 static void file_command (char *, int);
54 static void set_section_command (char *, int);
56 static void exec_files_info (struct target_ops
*);
58 static void init_exec_ops (void);
60 void _initialize_exec (void);
62 /* The target vector for executable files. */
64 struct target_ops exec_ops
;
66 /* True if the exec target is pushed on the stack. */
67 static int using_exec_ops
;
69 /* Whether to open exec and core files read-only or read-write. */
73 show_write_files (struct ui_file
*file
, int from_tty
,
74 struct cmd_list_element
*c
, const char *value
)
76 fprintf_filtered (file
, _("Writing into executable and core files is %s.\n"),
82 exec_open (char *args
, int from_tty
)
84 target_preopen (from_tty
);
85 exec_file_attach (args
, from_tty
);
88 /* Close and clear exec_bfd. If we end up with no target sections to
89 read memory from, this unpushes the exec_ops target. */
100 /* Removing target sections may close the exec_ops target.
101 Clear exec_bfd before doing so to prevent recursion. */
105 remove_target_sections (&exec_bfd
);
107 xfree (exec_filename
);
108 exec_filename
= NULL
;
112 /* This is the target_close implementation. Clears all target
113 sections and closes all executable bfds from all program spaces. */
116 exec_close_1 (struct target_ops
*self
)
121 struct program_space
*ss
;
122 struct cleanup
*old_chain
;
124 old_chain
= save_current_program_space ();
127 set_current_program_space (ss
);
129 /* Delete all target sections. */
131 (current_target_sections
,
132 -resize_section_table (current_target_sections
, 0));
137 do_cleanups (old_chain
);
142 exec_file_clear (int from_tty
)
144 /* Remove exec file. */
148 printf_unfiltered (_("No executable file now.\n"));
151 /* Set FILENAME as the new exec file.
153 This function is intended to be behave essentially the same
154 as exec_file_command, except that the latter will detect when
155 a target is being debugged, and will ask the user whether it
156 should be shut down first. (If the answer is "no", then the
157 new file is ignored.)
159 This file is used by exec_file_command, to do the work of opening
160 and processing the exec file after any prompting has happened.
162 And, it is used by child_attach, when the attach command was
163 given a pid but not a exec pathname, and the attach command could
164 figure out the pathname from the pid. (In this case, we shouldn't
165 ask the user whether the current target should be shut down --
166 we're supplying the exec pathname late for good reason.) */
169 exec_file_attach (char *filename
, int from_tty
)
171 /* Remove any previous exec file. */
174 /* Now open and digest the file the user requested, if any. */
179 printf_unfiltered (_("No executable file now.\n"));
181 set_gdbarch_from_file (NULL
);
185 struct cleanup
*cleanups
;
186 char *scratch_pathname
, *canonical_pathname
;
188 struct target_section
*sections
= NULL
, *sections_end
= NULL
;
191 scratch_chan
= openp (getenv ("PATH"), OPF_TRY_CWD_FIRST
, filename
,
192 write_files
? O_RDWR
| O_BINARY
: O_RDONLY
| O_BINARY
,
194 #if defined(__GO32__) || defined(_WIN32) || defined(__CYGWIN__)
195 if (scratch_chan
< 0)
197 char *exename
= alloca (strlen (filename
) + 5);
199 strcat (strcpy (exename
, filename
), ".exe");
200 scratch_chan
= openp (getenv ("PATH"), OPF_TRY_CWD_FIRST
, exename
,
201 write_files
? O_RDWR
| O_BINARY
: O_RDONLY
| O_BINARY
,
205 if (scratch_chan
< 0)
206 perror_with_name (filename
);
208 cleanups
= make_cleanup (xfree
, scratch_pathname
);
210 /* gdb_bfd_open (and its variants) prefers canonicalized pathname for
211 better BFD caching. */
212 canonical_pathname
= gdb_realpath (scratch_pathname
);
213 make_cleanup (xfree
, canonical_pathname
);
216 exec_bfd
= gdb_bfd_fopen (canonical_pathname
, gnutarget
,
217 FOPEN_RUB
, scratch_chan
);
219 exec_bfd
= gdb_bfd_open (canonical_pathname
, gnutarget
, scratch_chan
);
223 error (_("\"%s\": could not open as an executable file: %s"),
224 scratch_pathname
, bfd_errmsg (bfd_get_error ()));
227 gdb_assert (exec_filename
== NULL
);
228 exec_filename
= gdb_realpath_keepfile (scratch_pathname
);
230 if (!bfd_check_format_matches (exec_bfd
, bfd_object
, &matching
))
232 /* Make sure to close exec_bfd, or else "run" might try to use
235 error (_("\"%s\": not in executable format: %s"),
237 gdb_bfd_errmsg (bfd_get_error (), matching
));
240 if (build_section_table (exec_bfd
, §ions
, §ions_end
))
242 /* Make sure to close exec_bfd, or else "run" might try to use
245 error (_("\"%s\": can't find the file sections: %s"),
246 scratch_pathname
, bfd_errmsg (bfd_get_error ()));
249 exec_bfd_mtime
= bfd_get_mtime (exec_bfd
);
253 set_gdbarch_from_file (exec_bfd
);
255 /* Add the executable's sections to the current address spaces'
256 list of sections. This possibly pushes the exec_ops
258 add_target_sections (&exec_bfd
, sections
, sections_end
);
261 /* Tell display code (if any) about the changed file name. */
262 if (deprecated_exec_file_display_hook
)
263 (*deprecated_exec_file_display_hook
) (filename
);
265 do_cleanups (cleanups
);
267 bfd_cache_close_all ();
268 observer_notify_executable_changed ();
271 /* Process the first arg in ARGS as the new exec file.
273 Note that we have to explicitly ignore additional args, since we can
274 be called from file_command(), which also calls symbol_file_command()
275 which can take multiple args.
277 If ARGS is NULL, we just want to close the exec file. */
280 exec_file_command (char *args
, int from_tty
)
285 if (from_tty
&& target_has_execution
286 && !query (_("A program is being debugged already.\n"
287 "Are you sure you want to change the file? ")))
288 error (_("File not changed."));
292 struct cleanup
*cleanups
;
294 /* Scan through the args and pick up the first non option arg
297 argv
= gdb_buildargv (args
);
298 cleanups
= make_cleanup_freeargv (argv
);
300 for (; (*argv
!= NULL
) && (**argv
== '-'); argv
++)
304 error (_("No executable file name was specified"));
306 filename
= tilde_expand (*argv
);
307 make_cleanup (xfree
, filename
);
308 exec_file_attach (filename
, from_tty
);
310 do_cleanups (cleanups
);
313 exec_file_attach (NULL
, from_tty
);
316 /* Set both the exec file and the symbol file, in one command.
317 What a novelty. Why did GDB go through four major releases before this
318 command was added? */
321 file_command (char *arg
, int from_tty
)
323 /* FIXME, if we lose on reading the symbol file, we should revert
324 the exec file, but that's rough. */
325 exec_file_command (arg
, from_tty
);
326 symbol_file_command (arg
, from_tty
);
327 if (deprecated_file_changed_hook
)
328 deprecated_file_changed_hook (arg
);
332 /* Locate all mappable sections of a BFD file.
333 table_pp_char is a char * to get it through bfd_map_over_sections;
334 we cast it back to its proper type. */
337 add_to_section_table (bfd
*abfd
, struct bfd_section
*asect
,
340 struct target_section
**table_pp
= (struct target_section
**) table_pp_char
;
343 gdb_assert (abfd
== asect
->owner
);
345 /* Check the section flags, but do not discard zero-length sections, since
346 some symbols may still be attached to this section. For instance, we
347 encountered on sparc-solaris 2.10 a shared library with an empty .bss
348 section to which a symbol named "_end" was attached. The address
349 of this symbol still needs to be relocated. */
350 aflag
= bfd_get_section_flags (abfd
, asect
);
351 if (!(aflag
& SEC_ALLOC
))
354 (*table_pp
)->owner
= NULL
;
355 (*table_pp
)->the_bfd_section
= asect
;
356 (*table_pp
)->addr
= bfd_section_vma (abfd
, asect
);
357 (*table_pp
)->endaddr
= (*table_pp
)->addr
+ bfd_section_size (abfd
, asect
);
362 resize_section_table (struct target_section_table
*table
, int num_added
)
367 old_count
= table
->sections_end
- table
->sections
;
369 new_count
= num_added
+ old_count
;
373 table
->sections
= xrealloc (table
->sections
,
374 sizeof (struct target_section
) * new_count
);
375 table
->sections_end
= table
->sections
+ new_count
;
379 xfree (table
->sections
);
380 table
->sections
= table
->sections_end
= NULL
;
386 /* Builds a section table, given args BFD, SECTABLE_PTR, SECEND_PTR.
387 Returns 0 if OK, 1 on error. */
390 build_section_table (struct bfd
*some_bfd
, struct target_section
**start
,
391 struct target_section
**end
)
395 count
= bfd_count_sections (some_bfd
);
398 *start
= (struct target_section
*) xmalloc (count
* sizeof (**start
));
400 bfd_map_over_sections (some_bfd
, add_to_section_table
, (char *) end
);
401 if (*end
> *start
+ count
)
402 internal_error (__FILE__
, __LINE__
,
403 _("failed internal consistency check"));
404 /* We could realloc the table, but it probably loses for most files. */
408 /* Add the sections array defined by [SECTIONS..SECTIONS_END[ to the
409 current set of target sections. */
412 add_target_sections (void *owner
,
413 struct target_section
*sections
,
414 struct target_section
*sections_end
)
417 struct target_section_table
*table
= current_target_sections
;
419 count
= sections_end
- sections
;
423 int space
= resize_section_table (table
, count
);
426 for (i
= 0; i
< count
; ++i
)
428 table
->sections
[space
+ i
] = sections
[i
];
429 table
->sections
[space
+ i
].owner
= owner
;
432 /* If these are the first file sections we can provide memory
433 from, push the file_stratum target. */
437 push_target (&exec_ops
);
442 /* Add the sections of OBJFILE to the current set of target sections. */
445 add_target_sections_of_objfile (struct objfile
*objfile
)
447 struct target_section_table
*table
= current_target_sections
;
448 struct obj_section
*osect
;
451 struct target_section
*ts
;
456 /* Compute the number of sections to add. */
457 ALL_OBJFILE_OSECTIONS (objfile
, osect
)
459 if (bfd_get_section_size (osect
->the_bfd_section
) == 0)
467 space
= resize_section_table (table
, count
);
469 ts
= table
->sections
+ space
;
471 ALL_OBJFILE_OSECTIONS (objfile
, osect
)
473 if (bfd_get_section_size (osect
->the_bfd_section
) == 0)
476 gdb_assert (ts
< table
->sections
+ space
+ count
);
478 ts
->addr
= obj_section_addr (osect
);
479 ts
->endaddr
= obj_section_endaddr (osect
);
480 ts
->the_bfd_section
= osect
->the_bfd_section
;
481 ts
->owner
= (void *) objfile
;
487 /* Remove all target sections owned by OWNER.
488 OWNER must be the same value passed to add_target_sections. */
491 remove_target_sections (void *owner
)
493 struct target_section
*src
, *dest
;
494 struct target_section_table
*table
= current_target_sections
;
496 gdb_assert (owner
!= NULL
);
498 dest
= table
->sections
;
499 for (src
= table
->sections
; src
< table
->sections_end
; src
++)
500 if (src
->owner
!= owner
)
502 /* Keep this section. */
508 /* If we've dropped any sections, resize the section table. */
513 old_count
= resize_section_table (table
, dest
- src
);
515 /* If we don't have any more sections to read memory from,
516 remove the file_stratum target from the stack. */
517 if (old_count
+ (dest
- src
) == 0)
519 struct program_space
*pspace
;
522 if (pspace
->target_sections
.sections
523 != pspace
->target_sections
.sections_end
)
526 unpush_target (&exec_ops
);
534 section_table_available_memory (VEC(mem_range_s
) *memory
,
535 CORE_ADDR memaddr
, ULONGEST len
,
536 struct target_section
*sections
,
537 struct target_section
*sections_end
)
539 struct target_section
*p
;
541 for (p
= sections
; p
< sections_end
; p
++)
543 if ((bfd_get_section_flags (p
->the_bfd_section
->owner
,
545 & SEC_READONLY
) == 0)
548 /* Copy the meta-data, adjusted. */
549 if (mem_ranges_overlap (p
->addr
, p
->endaddr
- p
->addr
, memaddr
, len
))
551 ULONGEST lo1
, hi1
, lo2
, hi2
;
560 r
= VEC_safe_push (mem_range_s
, memory
, NULL
);
562 r
->start
= max (lo1
, lo2
);
563 r
->length
= min (hi1
, hi2
) - r
->start
;
570 enum target_xfer_status
571 section_table_xfer_memory_partial (gdb_byte
*readbuf
, const gdb_byte
*writebuf
,
572 ULONGEST offset
, ULONGEST len
,
573 ULONGEST
*xfered_len
,
574 struct target_section
*sections
,
575 struct target_section
*sections_end
,
576 const char *section_name
)
579 struct target_section
*p
;
580 ULONGEST memaddr
= offset
;
581 ULONGEST memend
= memaddr
+ len
;
584 internal_error (__FILE__
, __LINE__
,
585 _("failed internal consistency check"));
587 for (p
= sections
; p
< sections_end
; p
++)
589 struct bfd_section
*asect
= p
->the_bfd_section
;
590 bfd
*abfd
= asect
->owner
;
592 if (section_name
&& strcmp (section_name
, asect
->name
) != 0)
593 continue; /* not the section we need. */
594 if (memaddr
>= p
->addr
)
596 if (memend
<= p
->endaddr
)
598 /* Entire transfer is within this section. */
600 res
= bfd_set_section_contents (abfd
, asect
,
601 writebuf
, memaddr
- p
->addr
,
604 res
= bfd_get_section_contents (abfd
, asect
,
605 readbuf
, memaddr
- p
->addr
,
611 return TARGET_XFER_OK
;
614 return TARGET_XFER_EOF
;
616 else if (memaddr
>= p
->endaddr
)
618 /* This section ends before the transfer starts. */
623 /* This section overlaps the transfer. Just do half. */
624 len
= p
->endaddr
- memaddr
;
626 res
= bfd_set_section_contents (abfd
, asect
,
627 writebuf
, memaddr
- p
->addr
,
630 res
= bfd_get_section_contents (abfd
, asect
,
631 readbuf
, memaddr
- p
->addr
,
636 return TARGET_XFER_OK
;
639 return TARGET_XFER_EOF
;
644 return TARGET_XFER_EOF
; /* We can't help. */
647 static struct target_section_table
*
648 exec_get_section_table (struct target_ops
*ops
)
650 return current_target_sections
;
653 static enum target_xfer_status
654 exec_xfer_partial (struct target_ops
*ops
, enum target_object object
,
655 const char *annex
, gdb_byte
*readbuf
,
656 const gdb_byte
*writebuf
,
657 ULONGEST offset
, ULONGEST len
, ULONGEST
*xfered_len
)
659 struct target_section_table
*table
= target_get_section_table (ops
);
661 if (object
== TARGET_OBJECT_MEMORY
)
662 return section_table_xfer_memory_partial (readbuf
, writebuf
,
663 offset
, len
, xfered_len
,
668 return TARGET_XFER_E_IO
;
673 print_section_info (struct target_section_table
*t
, bfd
*abfd
)
675 struct gdbarch
*gdbarch
= gdbarch_from_bfd (abfd
);
676 struct target_section
*p
;
677 /* FIXME: 16 is not wide enough when gdbarch_addr_bit > 64. */
678 int wid
= gdbarch_addr_bit (gdbarch
) <= 32 ? 8 : 16;
680 printf_filtered ("\t`%s', ", bfd_get_filename (abfd
));
682 printf_filtered (_("file type %s.\n"), bfd_get_target (abfd
));
683 if (abfd
== exec_bfd
)
685 /* gcc-3.4 does not like the initialization in
686 <p == t->sections_end>. */
687 bfd_vma displacement
= 0;
690 for (p
= t
->sections
; p
< t
->sections_end
; p
++)
692 struct bfd_section
*psect
= p
->the_bfd_section
;
693 bfd
*pbfd
= psect
->owner
;
695 if ((bfd_get_section_flags (pbfd
, psect
) & (SEC_ALLOC
| SEC_LOAD
))
696 != (SEC_ALLOC
| SEC_LOAD
))
699 if (bfd_get_section_vma (pbfd
, psect
) <= abfd
->start_address
700 && abfd
->start_address
< (bfd_get_section_vma (pbfd
, psect
)
701 + bfd_get_section_size (psect
)))
703 displacement
= p
->addr
- bfd_get_section_vma (pbfd
, psect
);
707 if (p
== t
->sections_end
)
708 warning (_("Cannot find section for the entry point of %s."),
709 bfd_get_filename (abfd
));
711 entry_point
= gdbarch_addr_bits_remove (gdbarch
,
712 bfd_get_start_address (abfd
)
714 printf_filtered (_("\tEntry point: %s\n"),
715 paddress (gdbarch
, entry_point
));
717 for (p
= t
->sections
; p
< t
->sections_end
; p
++)
719 struct bfd_section
*psect
= p
->the_bfd_section
;
720 bfd
*pbfd
= psect
->owner
;
722 printf_filtered ("\t%s", hex_string_custom (p
->addr
, wid
));
723 printf_filtered (" - %s", hex_string_custom (p
->endaddr
, wid
));
725 /* FIXME: A format of "08l" is not wide enough for file offsets
726 larger than 4GB. OTOH, making it "016l" isn't desirable either
727 since most output will then be much wider than necessary. It
728 may make sense to test the size of the file and choose the
729 format string accordingly. */
730 /* FIXME: i18n: Need to rewrite this sentence. */
732 printf_filtered (" @ %s",
733 hex_string_custom (psect
->filepos
, 8));
734 printf_filtered (" is %s", bfd_section_name (pbfd
, psect
));
736 printf_filtered (" in %s", bfd_get_filename (pbfd
));
737 printf_filtered ("\n");
742 exec_files_info (struct target_ops
*t
)
745 print_section_info (current_target_sections
, exec_bfd
);
747 puts_filtered (_("\t<no file loaded>\n"));
751 set_section_command (char *args
, int from_tty
)
753 struct target_section
*p
;
756 unsigned long secaddr
;
759 struct target_section_table
*table
;
762 error (_("Must specify section name and its virtual address"));
764 /* Parse out section name. */
765 for (secname
= args
; !isspace (*args
); args
++);
766 seclen
= args
- secname
;
768 /* Parse out new virtual address. */
769 secaddr
= parse_and_eval_address (args
);
771 table
= current_target_sections
;
772 for (p
= table
->sections
; p
< table
->sections_end
; p
++)
774 if (!strncmp (secname
, bfd_section_name (p
->bfd
,
775 p
->the_bfd_section
), seclen
)
776 && bfd_section_name (p
->bfd
, p
->the_bfd_section
)[seclen
] == '\0')
778 offset
= secaddr
- p
->addr
;
780 p
->endaddr
+= offset
;
782 exec_files_info (&exec_ops
);
786 if (seclen
>= sizeof (secprint
))
787 seclen
= sizeof (secprint
) - 1;
788 strncpy (secprint
, secname
, seclen
);
789 secprint
[seclen
] = '\0';
790 error (_("Section %s not found"), secprint
);
793 /* If we can find a section in FILENAME with BFD index INDEX, adjust
797 exec_set_section_address (const char *filename
, int index
, CORE_ADDR address
)
799 struct target_section
*p
;
800 struct target_section_table
*table
;
802 table
= current_target_sections
;
803 for (p
= table
->sections
; p
< table
->sections_end
; p
++)
805 if (filename_cmp (filename
, p
->the_bfd_section
->owner
->filename
) == 0
806 && index
== p
->the_bfd_section
->index
)
808 p
->endaddr
+= address
- p
->addr
;
814 /* If mourn is being called in all the right places, this could be say
815 `gdb internal error' (since generic_mourn calls
816 breakpoint_init_inferior). */
819 ignore (struct target_ops
*ops
, struct gdbarch
*gdbarch
,
820 struct bp_target_info
*bp_tgt
)
826 exec_has_memory (struct target_ops
*ops
)
828 /* We can provide memory if we have any file/target sections to read
830 return (current_target_sections
->sections
831 != current_target_sections
->sections_end
);
834 static char *exec_make_note_section (struct target_ops
*self
, bfd
*, int *);
836 /* Fill in the exec file target vector. Very few entries need to be
842 exec_ops
.to_shortname
= "exec";
843 exec_ops
.to_longname
= "Local exec file";
844 exec_ops
.to_doc
= "Use an executable file as a target.\n\
845 Specify the filename of the executable file.";
846 exec_ops
.to_open
= exec_open
;
847 exec_ops
.to_close
= exec_close_1
;
848 exec_ops
.to_attach
= find_default_attach
;
849 exec_ops
.to_xfer_partial
= exec_xfer_partial
;
850 exec_ops
.to_get_section_table
= exec_get_section_table
;
851 exec_ops
.to_files_info
= exec_files_info
;
852 exec_ops
.to_insert_breakpoint
= ignore
;
853 exec_ops
.to_remove_breakpoint
= ignore
;
854 exec_ops
.to_create_inferior
= find_default_create_inferior
;
855 exec_ops
.to_stratum
= file_stratum
;
856 exec_ops
.to_has_memory
= exec_has_memory
;
857 exec_ops
.to_make_corefile_notes
= exec_make_note_section
;
858 exec_ops
.to_find_memory_regions
= objfile_find_memory_regions
;
859 exec_ops
.to_magic
= OPS_MAGIC
;
863 _initialize_exec (void)
865 struct cmd_list_element
*c
;
871 c
= add_cmd ("file", class_files
, file_command
, _("\
872 Use FILE as program to be debugged.\n\
873 It is read for its symbols, for getting the contents of pure memory,\n\
874 and it is the program executed when you use the `run' command.\n\
875 If FILE cannot be found as specified, your execution directory path\n\
876 ($PATH) is searched for a command of that name.\n\
877 No arg means to have no executable file and no symbols."), &cmdlist
);
878 set_cmd_completer (c
, filename_completer
);
881 c
= add_cmd ("exec-file", class_files
, exec_file_command
, _("\
882 Use FILE as program for getting contents of pure memory.\n\
883 If FILE cannot be found as specified, your execution directory path\n\
884 is searched for a command of that name.\n\
885 No arg means have no executable file."), &cmdlist
);
886 set_cmd_completer (c
, filename_completer
);
888 add_com ("section", class_files
, set_section_command
, _("\
889 Change the base address of section SECTION of the exec file to ADDR.\n\
890 This can be used if the exec file does not contain section addresses,\n\
891 (such as in the a.out format), or when the addresses specified in the\n\
892 file itself are wrong. Each section must be changed separately. The\n\
893 ``info files'' command lists all the sections and their addresses."));
895 add_setshow_boolean_cmd ("write", class_support
, &write_files
, _("\
896 Set writing into executable and core files."), _("\
897 Show writing into executable and core files."), NULL
,
900 &setlist
, &showlist
);
902 add_target_with_completer (&exec_ops
, filename_completer
);
906 exec_make_note_section (struct target_ops
*self
, bfd
*obfd
, int *note_size
)
908 error (_("Can't create a corefile"));