1 /* Handle Darwin shared libraries for GDB, the GNU Debugger.
3 Copyright (C) 2009-2012 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/>. */
30 #include "gdbthread.h"
32 #include "gdb_assert.h"
36 #include "solib-svr4.h"
38 #include "bfd-target.h"
42 #include "exceptions.h"
44 #include "mach-o/external.h"
46 struct gdb_dyld_image_info
48 /* Base address (which corresponds to the Mach-O header). */
49 CORE_ADDR mach_header
;
50 /* Image file path. */
52 /* st.m_time of image file. */
56 /* Content of inferior dyld_all_image_infos structure.
57 See /usr/include/mach-o/dyld_images.h for the documentation. */
58 struct gdb_dyld_all_image_infos
62 /* Number of images. */
64 /* Image description. */
66 /* Notifier (function called when a library is added or removed). */
70 /* Current all_image_infos version. */
71 #define DYLD_VERSION_MIN 1
72 #define DYLD_VERSION_MAX 12
74 /* Per PSPACE specific data. */
77 /* Address of structure dyld_all_image_infos in inferior. */
78 CORE_ADDR all_image_addr
;
80 /* Gdb copy of dyld_all_info_infos. */
81 struct gdb_dyld_all_image_infos all_image
;
84 /* Per-program-space data key. */
85 static const struct program_space_data
*solib_darwin_pspace_data
;
88 darwin_pspace_data_cleanup (struct program_space
*pspace
, void *arg
)
90 struct darwin_info
*info
;
92 info
= program_space_data (pspace
, solib_darwin_pspace_data
);
96 /* Get the current darwin data. If none is found yet, add it now. This
97 function always returns a valid object. */
99 static struct darwin_info
*
100 get_darwin_info (void)
102 struct darwin_info
*info
;
104 info
= program_space_data (current_program_space
, solib_darwin_pspace_data
);
108 info
= XZALLOC (struct darwin_info
);
109 set_program_space_data (current_program_space
,
110 solib_darwin_pspace_data
, info
);
114 /* Return non-zero if the version in dyld_all_image is known. */
117 darwin_dyld_version_ok (const struct darwin_info
*info
)
119 return info
->all_image
.version
>= DYLD_VERSION_MIN
120 && info
->all_image
.version
<= DYLD_VERSION_MAX
;
123 /* Read dyld_all_image from inferior. */
126 darwin_load_image_infos (struct darwin_info
*info
)
129 enum bfd_endian byte_order
= gdbarch_byte_order (target_gdbarch
);
130 struct type
*ptr_type
= builtin_type (target_gdbarch
)->builtin_data_ptr
;
133 /* If the structure address is not known, don't continue. */
134 if (info
->all_image_addr
== 0)
137 /* The structure has 4 fields: version (4 bytes), count (4 bytes),
138 info (pointer) and notifier (pointer). */
139 len
= 4 + 4 + 2 * ptr_type
->length
;
140 gdb_assert (len
<= sizeof (buf
));
141 memset (&info
->all_image
, 0, sizeof (info
->all_image
));
143 /* Read structure raw bytes from target. */
144 if (target_read_memory (info
->all_image_addr
, buf
, len
))
147 /* Extract the fields. */
148 info
->all_image
.version
= extract_unsigned_integer (buf
, 4, byte_order
);
149 if (!darwin_dyld_version_ok (info
))
152 info
->all_image
.count
= extract_unsigned_integer (buf
+ 4, 4, byte_order
);
153 info
->all_image
.info
= extract_typed_address (buf
+ 8, ptr_type
);
154 info
->all_image
.notifier
= extract_typed_address
155 (buf
+ 8 + ptr_type
->length
, ptr_type
);
158 /* Link map info to include in an allocated so_list entry. */
162 /* The target location of lm. */
166 struct darwin_so_list
170 /* Darwin specific data. */
174 /* Lookup the value for a specific symbol. */
177 lookup_symbol_from_bfd (bfd
*abfd
, char *symname
)
180 asymbol
**symbol_table
;
181 unsigned int number_of_symbols
;
183 CORE_ADDR symaddr
= 0;
185 storage_needed
= bfd_get_symtab_upper_bound (abfd
);
187 if (storage_needed
<= 0)
190 symbol_table
= (asymbol
**) xmalloc (storage_needed
);
191 number_of_symbols
= bfd_canonicalize_symtab (abfd
, symbol_table
);
193 for (i
= 0; i
< number_of_symbols
; i
++)
195 asymbol
*sym
= symbol_table
[i
];
197 if (strcmp (sym
->name
, symname
) == 0
198 && (sym
->section
->flags
& (SEC_CODE
| SEC_DATA
)) != 0)
200 /* BFD symbols are section relative. */
201 symaddr
= sym
->value
+ sym
->section
->vma
;
205 xfree (symbol_table
);
210 /* Return program interpreter string. */
213 find_program_interpreter (void)
215 gdb_byte
*buf
= NULL
;
217 /* If we have an exec_bfd, get the interpreter from the load commands. */
220 bfd_mach_o_load_command
*cmd
;
222 if (bfd_mach_o_lookup_command (exec_bfd
,
223 BFD_MACH_O_LC_LOAD_DYLINKER
, &cmd
) == 1)
224 return cmd
->command
.dylinker
.name_str
;
227 /* If we didn't find it, read from memory.
232 /* Not used. I don't see how the main symbol file can be found: the
233 interpreter name is needed and it is known from the executable file.
234 Note that darwin-nat.c implements pid_to_exec_file. */
237 open_symbol_file_object (void *from_ttyp
)
242 /* Build a list of currently loaded shared objects. See solib-svr4.c. */
244 static struct so_list
*
245 darwin_current_sos (void)
247 struct type
*ptr_type
= builtin_type (target_gdbarch
)->builtin_data_ptr
;
248 enum bfd_endian byte_order
= gdbarch_byte_order (target_gdbarch
);
249 int ptr_len
= TYPE_LENGTH (ptr_type
);
250 unsigned int image_info_size
;
251 struct so_list
*head
= NULL
;
252 struct so_list
*tail
= NULL
;
254 struct darwin_info
*info
= get_darwin_info ();
256 /* Be sure image infos are loaded. */
257 darwin_load_image_infos (info
);
259 if (!darwin_dyld_version_ok (info
))
262 image_info_size
= ptr_len
* 3;
264 /* Read infos for each solib.
265 The first entry was rumored to be the executable itself, but this is not
266 true when a large number of shared libraries are used (table expanded ?).
267 We now check all entries, but discard executable images. */
268 for (i
= 0; i
< info
->all_image
.count
; i
++)
270 CORE_ADDR iinfo
= info
->all_image
.info
+ i
* image_info_size
;
271 char buf
[image_info_size
];
274 struct mach_o_header_external hdr
;
275 unsigned long hdr_val
;
278 struct darwin_so_list
*dnew
;
280 struct cleanup
*old_chain
;
282 /* Read image info from inferior. */
283 if (target_read_memory (iinfo
, buf
, image_info_size
))
286 load_addr
= extract_typed_address (buf
, ptr_type
);
287 path_addr
= extract_typed_address (buf
+ ptr_len
, ptr_type
);
289 /* Read Mach-O header from memory. */
290 if (target_read_memory (load_addr
, (char *) &hdr
, sizeof (hdr
) - 4))
292 /* Discard wrong magic numbers. Shouldn't happen. */
293 hdr_val
= extract_unsigned_integer
294 (hdr
.magic
, sizeof (hdr
.magic
), byte_order
);
295 if (hdr_val
!= BFD_MACH_O_MH_MAGIC
&& hdr_val
!= BFD_MACH_O_MH_MAGIC_64
)
297 /* Discard executable. Should happen only once. */
298 hdr_val
= extract_unsigned_integer
299 (hdr
.filetype
, sizeof (hdr
.filetype
), byte_order
);
300 if (hdr_val
== BFD_MACH_O_MH_EXECUTE
)
303 target_read_string (path_addr
, &file_path
,
304 SO_NAME_MAX_PATH_SIZE
- 1, &errcode
);
308 /* Create and fill the new so_list element. */
309 dnew
= XZALLOC (struct darwin_so_list
);
311 old_chain
= make_cleanup (xfree
, dnew
);
313 new->lm_info
= &dnew
->li
;
315 strncpy (new->so_name
, file_path
, SO_NAME_MAX_PATH_SIZE
- 1);
316 new->so_name
[SO_NAME_MAX_PATH_SIZE
- 1] = '\0';
317 strcpy (new->so_original_name
, new->so_name
);
319 new->lm_info
->lm_addr
= load_addr
;
327 discard_cleanups (old_chain
);
333 /* Return 1 if PC lies in the dynamic symbol resolution code of the
337 darwin_in_dynsym_resolve_code (CORE_ADDR pc
)
343 /* No special symbol handling. */
346 darwin_special_symbol_handling (void)
350 /* Extract dyld_all_image_addr when the process was just created, assuming the
351 current PC is at the entry of the dynamic linker. */
354 darwin_solib_get_all_image_info_addr_at_init (struct darwin_info
*info
)
356 gdb_byte
*interp_name
;
357 CORE_ADDR load_addr
= 0;
358 bfd
*dyld_bfd
= NULL
;
360 /* This method doesn't work with an attached process. */
361 if (current_inferior ()->attach_flag
)
364 /* Find the program interpreter. */
365 interp_name
= find_program_interpreter ();
369 /* Create a bfd for the interpreter. */
370 dyld_bfd
= bfd_openr (interp_name
, gnutarget
);
375 sub
= bfd_mach_o_fat_extract (dyld_bfd
, bfd_object
,
376 gdbarch_bfd_arch_info (target_gdbarch
));
381 bfd_close (dyld_bfd
);
388 /* We find the dynamic linker's base address by examining
389 the current pc (which should point at the entry point for the
390 dynamic linker) and subtracting the offset of the entry point. */
391 load_addr
= (regcache_read_pc (get_current_regcache ())
392 - bfd_get_start_address (dyld_bfd
));
394 /* Now try to set a breakpoint in the dynamic linker. */
395 info
->all_image_addr
=
396 lookup_symbol_from_bfd (dyld_bfd
, "_dyld_all_image_infos");
398 bfd_close (dyld_bfd
);
400 if (info
->all_image_addr
== 0)
403 info
->all_image_addr
+= load_addr
;
406 /* Extract dyld_all_image_addr reading it from
407 TARGET_OBJECT_DARWIN_DYLD_INFO. */
410 darwin_solib_read_all_image_info_addr (struct darwin_info
*info
)
412 gdb_byte buf
[8 + 8 + 4];
414 enum bfd_endian byte_order
= gdbarch_byte_order (target_gdbarch
);
416 len
= target_read (¤t_target
, TARGET_OBJECT_DARWIN_DYLD_INFO
, NULL
,
417 buf
, 0, sizeof (buf
));
418 if (len
!= sizeof (buf
))
421 info
->all_image_addr
= extract_unsigned_integer (buf
, 8, byte_order
);
424 /* Shared library startup support. See documentation in solib-svr4.c. */
427 darwin_solib_create_inferior_hook (int from_tty
)
429 struct darwin_info
*info
= get_darwin_info ();
431 info
->all_image_addr
= 0;
433 darwin_solib_read_all_image_info_addr (info
);
435 if (info
->all_image_addr
== 0)
436 darwin_solib_get_all_image_info_addr_at_init (info
);
438 if (info
->all_image_addr
== 0)
441 darwin_load_image_infos (info
);
443 if (darwin_dyld_version_ok (info
))
444 create_solib_event_breakpoint (target_gdbarch
, info
->all_image
.notifier
);
448 darwin_clear_solib (void)
450 struct darwin_info
*info
= get_darwin_info ();
452 info
->all_image_addr
= 0;
453 info
->all_image
.version
= 0;
457 darwin_free_so (struct so_list
*so
)
461 /* The section table is built from bfd sections using bfd VMAs.
462 Relocate these VMAs according to solib info. */
465 darwin_relocate_section_addresses (struct so_list
*so
,
466 struct target_section
*sec
)
468 sec
->addr
+= so
->lm_info
->lm_addr
;
469 sec
->endaddr
+= so
->lm_info
->lm_addr
;
471 /* Best effort to set addr_high/addr_low. This is used only by
472 'info sharedlibary'. */
473 if (so
->addr_high
== 0)
475 so
->addr_low
= sec
->addr
;
476 so
->addr_high
= sec
->endaddr
;
478 if (sec
->endaddr
> so
->addr_high
)
479 so
->addr_high
= sec
->endaddr
;
480 if (sec
->addr
< so
->addr_low
)
481 so
->addr_low
= sec
->addr
;
484 static struct symbol
*
485 darwin_lookup_lib_symbol (const struct objfile
*objfile
,
487 const domain_enum domain
)
493 darwin_bfd_open (char *pathname
)
495 char *found_pathname
;
500 /* Search for shared library file. */
501 found_pathname
= solib_find (pathname
, &found_file
);
502 if (found_pathname
== NULL
)
503 perror_with_name (pathname
);
505 /* Open bfd for shared library. */
506 abfd
= solib_bfd_fopen (found_pathname
, found_file
);
508 res
= bfd_mach_o_fat_extract (abfd
, bfd_object
,
509 gdbarch_bfd_arch_info (target_gdbarch
));
513 make_cleanup (xfree
, found_pathname
);
514 error (_("`%s': not a shared-library: %s"),
515 found_pathname
, bfd_errmsg (bfd_get_error ()));
518 /* Make sure that the filename is malloc'ed. The current filename
519 for fat-binaries BFDs is a name that was generated by BFD, usually
520 a static string containing the name of the architecture. */
521 res
->filename
= xstrdup (pathname
);
526 struct target_so_ops darwin_so_ops
;
528 /* -Wmissing-prototypes */
529 extern initialize_file_ftype _initialize_darwin_solib
;
532 _initialize_darwin_solib (void)
534 solib_darwin_pspace_data
535 = register_program_space_data_with_cleanup (darwin_pspace_data_cleanup
);
537 darwin_so_ops
.relocate_section_addresses
= darwin_relocate_section_addresses
;
538 darwin_so_ops
.free_so
= darwin_free_so
;
539 darwin_so_ops
.clear_solib
= darwin_clear_solib
;
540 darwin_so_ops
.solib_create_inferior_hook
= darwin_solib_create_inferior_hook
;
541 darwin_so_ops
.special_symbol_handling
= darwin_special_symbol_handling
;
542 darwin_so_ops
.current_sos
= darwin_current_sos
;
543 darwin_so_ops
.open_symbol_file_object
= open_symbol_file_object
;
544 darwin_so_ops
.in_dynsym_resolve_code
= darwin_in_dynsym_resolve_code
;
545 darwin_so_ops
.lookup_lib_global_symbol
= darwin_lookup_lib_symbol
;
546 darwin_so_ops
.bfd_open
= darwin_bfd_open
;