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"
45 struct gdb_dyld_image_info
47 /* Base address (which corresponds to the Mach-O header). */
48 CORE_ADDR mach_header
;
49 /* Image file path. */
51 /* st.m_time of image file. */
55 /* Content of inferior dyld_all_image_infos structure.
56 See /usr/include/mach-o/dyld_images.h for the documentation. */
57 struct gdb_dyld_all_image_infos
61 /* Number of images. */
63 /* Image description. */
65 /* Notifier (function called when a library is added or removed). */
69 /* Current all_image_infos version. */
70 #define DYLD_VERSION_MIN 1
71 #define DYLD_VERSION_MAX 12
73 /* Address of structure dyld_all_image_infos in inferior. */
74 static CORE_ADDR dyld_all_image_addr
;
76 /* Gdb copy of dyld_all_info_infos. */
77 static struct gdb_dyld_all_image_infos dyld_all_image
;
79 /* Return non-zero if the version in dyld_all_image is known. */
82 darwin_dyld_version_ok (void)
84 return dyld_all_image
.version
>= DYLD_VERSION_MIN
85 && dyld_all_image
.version
<= DYLD_VERSION_MAX
;
88 /* Read dyld_all_image from inferior. */
91 darwin_load_image_infos (void)
94 enum bfd_endian byte_order
= gdbarch_byte_order (target_gdbarch
);
95 struct type
*ptr_type
= builtin_type (target_gdbarch
)->builtin_data_ptr
;
98 /* If the structure address is not known, don't continue. */
99 if (dyld_all_image_addr
== 0)
102 /* The structure has 4 fields: version (4 bytes), count (4 bytes),
103 info (pointer) and notifier (pointer). */
104 len
= 4 + 4 + 2 * ptr_type
->length
;
105 gdb_assert (len
<= sizeof (buf
));
106 memset (&dyld_all_image
, 0, sizeof (dyld_all_image
));
108 /* Read structure raw bytes from target. */
109 if (target_read_memory (dyld_all_image_addr
, buf
, len
))
112 /* Extract the fields. */
113 dyld_all_image
.version
= extract_unsigned_integer (buf
, 4, byte_order
);
114 if (!darwin_dyld_version_ok ())
117 dyld_all_image
.count
= extract_unsigned_integer (buf
+ 4, 4, byte_order
);
118 dyld_all_image
.info
= extract_typed_address (buf
+ 8, ptr_type
);
119 dyld_all_image
.notifier
= extract_typed_address
120 (buf
+ 8 + ptr_type
->length
, ptr_type
);
123 /* Link map info to include in an allocated so_list entry. */
127 /* The target location of lm. */
131 struct darwin_so_list
135 /* Darwin specific data. */
139 /* Lookup the value for a specific symbol. */
142 lookup_symbol_from_bfd (bfd
*abfd
, char *symname
)
145 asymbol
**symbol_table
;
146 unsigned int number_of_symbols
;
148 CORE_ADDR symaddr
= 0;
150 storage_needed
= bfd_get_symtab_upper_bound (abfd
);
152 if (storage_needed
<= 0)
155 symbol_table
= (asymbol
**) xmalloc (storage_needed
);
156 number_of_symbols
= bfd_canonicalize_symtab (abfd
, symbol_table
);
158 for (i
= 0; i
< number_of_symbols
; i
++)
160 asymbol
*sym
= symbol_table
[i
];
162 if (strcmp (sym
->name
, symname
) == 0
163 && (sym
->section
->flags
& (SEC_CODE
| SEC_DATA
)) != 0)
165 /* BFD symbols are section relative. */
166 symaddr
= sym
->value
+ sym
->section
->vma
;
170 xfree (symbol_table
);
175 /* Return program interpreter string. */
178 find_program_interpreter (void)
180 gdb_byte
*buf
= NULL
;
182 /* If we have an exec_bfd, get the interpreter from the load commands. */
185 bfd_mach_o_load_command
*cmd
;
187 if (bfd_mach_o_lookup_command (exec_bfd
,
188 BFD_MACH_O_LC_LOAD_DYLINKER
, &cmd
) == 1)
189 return cmd
->command
.dylinker
.name_str
;
192 /* If we didn't find it, read from memory.
197 /* Not used. I don't see how the main symbol file can be found: the
198 interpreter name is needed and it is known from the executable file.
199 Note that darwin-nat.c implements pid_to_exec_file. */
202 open_symbol_file_object (void *from_ttyp
)
207 /* Build a list of currently loaded shared objects. See solib-svr4.c. */
209 static struct so_list
*
210 darwin_current_sos (void)
212 struct type
*ptr_type
= builtin_type (target_gdbarch
)->builtin_data_ptr
;
213 int ptr_len
= TYPE_LENGTH (ptr_type
);
214 unsigned int image_info_size
;
216 struct so_list
*head
= NULL
;
217 struct so_list
*tail
= NULL
;
220 /* Be sure image infos are loaded. */
221 darwin_load_image_infos ();
223 if (!darwin_dyld_version_ok ())
226 image_info_size
= ptr_len
* 3;
228 /* Read infos for each solib.
229 This first entry is ignored as this is the executable itself. */
230 for (i
= 1; i
< dyld_all_image
.count
; i
++)
232 CORE_ADDR info
= dyld_all_image
.info
+ i
* image_info_size
;
233 char buf
[image_info_size
];
238 struct darwin_so_list
*dnew
;
240 struct cleanup
*old_chain
;
242 /* Read image info from inferior. */
243 if (target_read_memory (info
, buf
, image_info_size
))
246 load_addr
= extract_typed_address (buf
, ptr_type
);
247 path_addr
= extract_typed_address (buf
+ ptr_len
, ptr_type
);
249 target_read_string (path_addr
, &file_path
,
250 SO_NAME_MAX_PATH_SIZE
- 1, &errcode
);
254 /* Create and fill the new so_list element. */
255 dnew
= XZALLOC (struct darwin_so_list
);
257 old_chain
= make_cleanup (xfree
, dnew
);
259 new->lm_info
= &dnew
->li
;
261 strncpy (new->so_name
, file_path
, SO_NAME_MAX_PATH_SIZE
- 1);
262 new->so_name
[SO_NAME_MAX_PATH_SIZE
- 1] = '\0';
263 strcpy (new->so_original_name
, new->so_name
);
265 new->lm_info
->lm_addr
= load_addr
;
273 discard_cleanups (old_chain
);
279 /* Return 1 if PC lies in the dynamic symbol resolution code of the
283 darwin_in_dynsym_resolve_code (CORE_ADDR pc
)
289 /* No special symbol handling. */
292 darwin_special_symbol_handling (void)
296 /* Extract dyld_all_image_addr when the process was just created, assuming the
297 current PC is at the entry of the dynamic linker. */
300 darwin_solib_get_all_image_info_addr_at_init (void)
302 gdb_byte
*interp_name
;
303 CORE_ADDR load_addr
= 0;
304 bfd
*dyld_bfd
= NULL
;
306 /* This method doesn't work with an attached process. */
307 if (current_inferior ()->attach_flag
)
310 /* Find the program interpreter. */
311 interp_name
= find_program_interpreter ();
315 /* Create a bfd for the interpreter. */
316 dyld_bfd
= bfd_openr (interp_name
, gnutarget
);
321 sub
= bfd_mach_o_fat_extract (dyld_bfd
, bfd_object
,
322 gdbarch_bfd_arch_info (target_gdbarch
));
327 bfd_close (dyld_bfd
);
334 /* We find the dynamic linker's base address by examining
335 the current pc (which should point at the entry point for the
336 dynamic linker) and subtracting the offset of the entry point. */
337 load_addr
= (regcache_read_pc (get_current_regcache ())
338 - bfd_get_start_address (dyld_bfd
));
340 /* Now try to set a breakpoint in the dynamic linker. */
341 dyld_all_image_addr
=
342 lookup_symbol_from_bfd (dyld_bfd
, "_dyld_all_image_infos");
344 bfd_close (dyld_bfd
);
346 if (dyld_all_image_addr
== 0)
349 dyld_all_image_addr
+= load_addr
;
352 /* Extract dyld_all_image_addr reading it from
353 TARGET_OBJECT_DARWIN_DYLD_INFO. */
356 darwin_solib_read_all_image_info_addr (void)
358 gdb_byte buf
[8 + 8 + 4];
360 enum bfd_endian byte_order
= gdbarch_byte_order (target_gdbarch
);
362 len
= target_read (¤t_target
, TARGET_OBJECT_DARWIN_DYLD_INFO
, NULL
,
363 buf
, 0, sizeof (buf
));
364 if (len
!= sizeof (buf
))
367 dyld_all_image_addr
= extract_unsigned_integer (buf
, 8, byte_order
);
370 /* Shared library startup support. See documentation in solib-svr4.c. */
373 darwin_solib_create_inferior_hook (int from_tty
)
375 dyld_all_image_addr
= 0;
377 darwin_solib_read_all_image_info_addr ();
379 if (dyld_all_image_addr
== 0)
380 darwin_solib_get_all_image_info_addr_at_init ();
382 if (dyld_all_image_addr
== 0)
385 darwin_load_image_infos ();
387 if (darwin_dyld_version_ok ())
388 create_solib_event_breakpoint (target_gdbarch
, dyld_all_image
.notifier
);
392 darwin_clear_solib (void)
394 dyld_all_image_addr
= 0;
395 dyld_all_image
.version
= 0;
399 darwin_free_so (struct so_list
*so
)
403 /* The section table is built from bfd sections using bfd VMAs.
404 Relocate these VMAs according to solib info. */
407 darwin_relocate_section_addresses (struct so_list
*so
,
408 struct target_section
*sec
)
410 sec
->addr
+= so
->lm_info
->lm_addr
;
411 sec
->endaddr
+= so
->lm_info
->lm_addr
;
413 /* Best effort to set addr_high/addr_low. This is used only by
414 'info sharedlibary'. */
415 if (so
->addr_high
== 0)
417 so
->addr_low
= sec
->addr
;
418 so
->addr_high
= sec
->endaddr
;
420 if (sec
->endaddr
> so
->addr_high
)
421 so
->addr_high
= sec
->endaddr
;
422 if (sec
->addr
< so
->addr_low
)
423 so
->addr_low
= sec
->addr
;
426 static struct symbol
*
427 darwin_lookup_lib_symbol (const struct objfile
*objfile
,
429 const domain_enum domain
)
435 darwin_bfd_open (char *pathname
)
437 char *found_pathname
;
442 /* Search for shared library file. */
443 found_pathname
= solib_find (pathname
, &found_file
);
444 if (found_pathname
== NULL
)
445 perror_with_name (pathname
);
447 /* Open bfd for shared library. */
448 abfd
= solib_bfd_fopen (found_pathname
, found_file
);
450 res
= bfd_mach_o_fat_extract (abfd
, bfd_object
,
451 gdbarch_bfd_arch_info (target_gdbarch
));
455 make_cleanup (xfree
, found_pathname
);
456 error (_("`%s': not a shared-library: %s"),
457 found_pathname
, bfd_errmsg (bfd_get_error ()));
462 struct target_so_ops darwin_so_ops
;
465 _initialize_darwin_solib (void)
467 darwin_so_ops
.relocate_section_addresses
= darwin_relocate_section_addresses
;
468 darwin_so_ops
.free_so
= darwin_free_so
;
469 darwin_so_ops
.clear_solib
= darwin_clear_solib
;
470 darwin_so_ops
.solib_create_inferior_hook
= darwin_solib_create_inferior_hook
;
471 darwin_so_ops
.special_symbol_handling
= darwin_special_symbol_handling
;
472 darwin_so_ops
.current_sos
= darwin_current_sos
;
473 darwin_so_ops
.open_symbol_file_object
= open_symbol_file_object
;
474 darwin_so_ops
.in_dynsym_resolve_code
= darwin_in_dynsym_resolve_code
;
475 darwin_so_ops
.lookup_lib_global_symbol
= darwin_lookup_lib_symbol
;
476 darwin_so_ops
.bfd_open
= darwin_bfd_open
;