1 /* Handle SVR4 shared libraries for GDB, the GNU Debugger.
3 Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000,
4 2001, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 51 Franklin Street, Fifth Floor,
21 Boston, MA 02110-1301, USA. */
25 #include "elf/external.h"
26 #include "elf/common.h"
37 #include "gdb_assert.h"
41 #include "solib-svr4.h"
43 #include "bfd-target.h"
47 static struct link_map_offsets
*svr4_fetch_link_map_offsets (void);
48 static int svr4_have_link_map_offsets (void);
50 /* This hook is set to a function that provides native link map
51 offsets if the code in solib-legacy.c is linked in. */
52 struct link_map_offsets
*(*legacy_svr4_fetch_link_map_offsets_hook
) (void);
54 /* Link map info to include in an allocated so_list entry */
58 /* Pointer to copy of link map from inferior. The type is char *
59 rather than void *, so that we may use byte offsets to find the
60 various fields without the need for a cast. */
63 /* Amount by which addresses in the binary should be relocated to
64 match the inferior. This could most often be taken directly
65 from lm, but when prelinking is involved and the prelink base
66 address changes, we may need a different offset, we want to
67 warn about the difference and compute it only once. */
71 /* On SVR4 systems, a list of symbols in the dynamic linker where
72 GDB can try to place a breakpoint to monitor shared library
75 If none of these symbols are found, or other errors occur, then
76 SVR4 systems will fall back to using a symbol as the "startup
77 mapping complete" breakpoint address. */
79 static char *solib_break_names
[] =
87 /* On the 64-bit PowerPC, the linker symbol with the same name as
88 the C function points to a function descriptor, not to the entry
89 point. The linker symbol whose name is the C function name
90 prefixed with a '.' points to the function's entry point. So
91 when we look through this table, we ignore symbols that point
92 into the data section (thus skipping the descriptor's symbol),
93 and eventually try this one, giving us the real entry point
100 #define BKPT_AT_SYMBOL 1
102 #if defined (BKPT_AT_SYMBOL)
103 static char *bkpt_names
[] =
105 #ifdef SOLIB_BKPT_NAME
106 SOLIB_BKPT_NAME
, /* Prefer configured name if it exists. */
115 static char *main_name_list
[] =
121 /* link map access functions */
124 LM_ADDR_FROM_LINK_MAP (struct so_list
*so
)
126 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
128 return extract_typed_address (so
->lm_info
->lm
+ lmo
->l_addr_offset
,
129 builtin_type_void_data_ptr
);
133 HAS_LM_DYNAMIC_FROM_LINK_MAP ()
135 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
137 return lmo
->l_ld_offset
>= 0;
141 LM_DYNAMIC_FROM_LINK_MAP (struct so_list
*so
)
143 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
145 return extract_typed_address (so
->lm_info
->lm
+ lmo
->l_ld_offset
,
146 builtin_type_void_data_ptr
);
150 LM_ADDR_CHECK (struct so_list
*so
, bfd
*abfd
)
152 if (so
->lm_info
->l_addr
== (CORE_ADDR
)-1)
154 struct bfd_section
*dyninfo_sect
;
155 CORE_ADDR l_addr
, l_dynaddr
, dynaddr
, align
= 0x1000;
157 l_addr
= LM_ADDR_FROM_LINK_MAP (so
);
159 if (! abfd
|| ! HAS_LM_DYNAMIC_FROM_LINK_MAP ())
162 l_dynaddr
= LM_DYNAMIC_FROM_LINK_MAP (so
);
164 dyninfo_sect
= bfd_get_section_by_name (abfd
, ".dynamic");
165 if (dyninfo_sect
== NULL
)
168 dynaddr
= bfd_section_vma (abfd
, dyninfo_sect
);
170 if (dynaddr
+ l_addr
!= l_dynaddr
)
172 if (bfd_get_flavour (abfd
) == bfd_target_elf_flavour
)
174 Elf_Internal_Ehdr
*ehdr
= elf_tdata (abfd
)->elf_header
;
175 Elf_Internal_Phdr
*phdr
= elf_tdata (abfd
)->phdr
;
180 for (i
= 0; i
< ehdr
->e_phnum
; i
++)
181 if (phdr
[i
].p_type
== PT_LOAD
&& phdr
[i
].p_align
> align
)
182 align
= phdr
[i
].p_align
;
185 /* Turn it into a mask. */
188 /* If the changes match the alignment requirements, we
189 assume we're using a core file that was generated by the
190 same binary, just prelinked with a different base offset.
191 If it doesn't match, we may have a different binary, the
192 same binary with the dynamic table loaded at an unrelated
193 location, or anything, really. To avoid regressions,
194 don't adjust the base offset in the latter case, although
195 odds are that, if things really changed, debugging won't
197 if ((l_addr
& align
) == 0 && ((dynaddr
- l_dynaddr
) & align
) == 0)
199 l_addr
= l_dynaddr
- dynaddr
;
201 warning (_(".dynamic section for \"%s\" "
202 "is not at the expected address"), so
->so_name
);
203 warning (_("difference appears to be caused by prelink, "
204 "adjusting expectations"));
207 warning (_(".dynamic section for \"%s\" "
208 "is not at the expected address "
209 "(wrong library or version mismatch?)"), so
->so_name
);
213 so
->lm_info
->l_addr
= l_addr
;
216 return so
->lm_info
->l_addr
;
220 LM_NEXT (struct so_list
*so
)
222 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
224 return extract_typed_address (so
->lm_info
->lm
+ lmo
->l_next_offset
,
225 builtin_type_void_data_ptr
);
229 LM_NAME (struct so_list
*so
)
231 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
233 return extract_typed_address (so
->lm_info
->lm
+ lmo
->l_name_offset
,
234 builtin_type_void_data_ptr
);
238 IGNORE_FIRST_LINK_MAP_ENTRY (struct so_list
*so
)
240 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
242 /* Assume that everything is a library if the dynamic loader was loaded
243 late by a static executable. */
244 if (bfd_get_section_by_name (exec_bfd
, ".dynamic") == NULL
)
247 return extract_typed_address (so
->lm_info
->lm
+ lmo
->l_prev_offset
,
248 builtin_type_void_data_ptr
) == 0;
251 static CORE_ADDR debug_base
; /* Base of dynamic linker structures */
253 /* Validity flag for debug_loader_offset. */
254 static int debug_loader_offset_p
;
256 /* Load address for the dynamic linker, inferred. */
257 static CORE_ADDR debug_loader_offset
;
259 /* Name of the dynamic linker, valid if debug_loader_offset_p. */
260 static char *debug_loader_name
;
262 /* Local function prototypes */
264 static int match_main (char *);
266 static CORE_ADDR
bfd_lookup_symbol (bfd
*, char *, flagword
);
272 bfd_lookup_symbol -- lookup the value for a specific symbol
276 CORE_ADDR bfd_lookup_symbol (bfd *abfd, char *symname, flagword sect_flags)
280 An expensive way to lookup the value of a single symbol for
281 bfd's that are only temporary anyway. This is used by the
282 shared library support to find the address of the debugger
283 interface structures in the shared library.
285 If SECT_FLAGS is non-zero, only match symbols in sections whose
286 flags include all those in SECT_FLAGS.
288 Note that 0 is specifically allowed as an error return (no
293 bfd_lookup_symbol (bfd
*abfd
, char *symname
, flagword sect_flags
)
297 asymbol
**symbol_table
;
298 unsigned int number_of_symbols
;
300 struct cleanup
*back_to
;
301 CORE_ADDR symaddr
= 0;
303 storage_needed
= bfd_get_symtab_upper_bound (abfd
);
305 if (storage_needed
> 0)
307 symbol_table
= (asymbol
**) xmalloc (storage_needed
);
308 back_to
= make_cleanup (xfree
, symbol_table
);
309 number_of_symbols
= bfd_canonicalize_symtab (abfd
, symbol_table
);
311 for (i
= 0; i
< number_of_symbols
; i
++)
313 sym
= *symbol_table
++;
314 if (strcmp (sym
->name
, symname
) == 0
315 && (sym
->section
->flags
& sect_flags
) == sect_flags
)
317 /* Bfd symbols are section relative. */
318 symaddr
= sym
->value
+ sym
->section
->vma
;
322 do_cleanups (back_to
);
328 /* On FreeBSD, the dynamic linker is stripped by default. So we'll
329 have to check the dynamic string table too. */
331 storage_needed
= bfd_get_dynamic_symtab_upper_bound (abfd
);
333 if (storage_needed
> 0)
335 symbol_table
= (asymbol
**) xmalloc (storage_needed
);
336 back_to
= make_cleanup (xfree
, symbol_table
);
337 number_of_symbols
= bfd_canonicalize_dynamic_symtab (abfd
, symbol_table
);
339 for (i
= 0; i
< number_of_symbols
; i
++)
341 sym
= *symbol_table
++;
343 if (strcmp (sym
->name
, symname
) == 0
344 && (sym
->section
->flags
& sect_flags
) == sect_flags
)
346 /* Bfd symbols are section relative. */
347 symaddr
= sym
->value
+ sym
->section
->vma
;
351 do_cleanups (back_to
);
361 elf_locate_base -- locate the base address of dynamic linker structs
362 for SVR4 elf targets.
366 CORE_ADDR elf_locate_base (void)
370 For SVR4 elf targets the address of the dynamic linker's runtime
371 structure is contained within the dynamic info section in the
372 executable file. The dynamic section is also mapped into the
373 inferior address space. Because the runtime loader fills in the
374 real address before starting the inferior, we have to read in the
375 dynamic info section from the inferior address space.
376 If there are any errors while trying to find the address, we
377 silently return 0, otherwise the found address is returned.
382 elf_locate_base (void)
384 struct bfd_section
*dyninfo_sect
;
385 int dyninfo_sect_size
;
386 CORE_ADDR dyninfo_addr
;
391 /* Find the start address of the .dynamic section. */
392 dyninfo_sect
= bfd_get_section_by_name (exec_bfd
, ".dynamic");
393 if (dyninfo_sect
== NULL
)
395 /* This may be a static executable. Look for the symbol
396 conventionally named _r_debug, as a last resort. */
397 struct minimal_symbol
*msymbol
;
399 msymbol
= lookup_minimal_symbol ("_r_debug", NULL
, symfile_objfile
);
401 return SYMBOL_VALUE_ADDRESS (msymbol
);
406 dyninfo_addr
= bfd_section_vma (exec_bfd
, dyninfo_sect
);
408 /* Read in .dynamic section, silently ignore errors. */
409 dyninfo_sect_size
= bfd_section_size (exec_bfd
, dyninfo_sect
);
410 buf
= alloca (dyninfo_sect_size
);
411 if (target_read_memory (dyninfo_addr
, buf
, dyninfo_sect_size
))
414 /* Find the DT_DEBUG entry in the the .dynamic section.
415 For mips elf we look for DT_MIPS_RLD_MAP, mips elf apparently has
416 no DT_DEBUG entries. */
418 arch_size
= bfd_get_arch_size (exec_bfd
);
419 if (arch_size
== -1) /* failure */
424 for (bufend
= buf
+ dyninfo_sect_size
;
426 buf
+= sizeof (Elf32_External_Dyn
))
428 Elf32_External_Dyn
*x_dynp
= (Elf32_External_Dyn
*) buf
;
432 dyn_tag
= bfd_h_get_32 (exec_bfd
, (bfd_byte
*) x_dynp
->d_tag
);
433 if (dyn_tag
== DT_NULL
)
435 else if (dyn_tag
== DT_DEBUG
)
437 dyn_ptr
= bfd_h_get_32 (exec_bfd
,
438 (bfd_byte
*) x_dynp
->d_un
.d_ptr
);
441 else if (dyn_tag
== DT_MIPS_RLD_MAP
)
444 int pbuf_size
= TYPE_LENGTH (builtin_type_void_data_ptr
);
446 pbuf
= alloca (pbuf_size
);
447 /* DT_MIPS_RLD_MAP contains a pointer to the address
448 of the dynamic link structure. */
449 dyn_ptr
= bfd_h_get_32 (exec_bfd
,
450 (bfd_byte
*) x_dynp
->d_un
.d_ptr
);
451 if (target_read_memory (dyn_ptr
, pbuf
, pbuf_size
))
453 return extract_typed_address (pbuf
, builtin_type_void_data_ptr
);
457 else /* 64-bit elf */
459 for (bufend
= buf
+ dyninfo_sect_size
;
461 buf
+= sizeof (Elf64_External_Dyn
))
463 Elf64_External_Dyn
*x_dynp
= (Elf64_External_Dyn
*) buf
;
467 dyn_tag
= bfd_h_get_64 (exec_bfd
, (bfd_byte
*) x_dynp
->d_tag
);
468 if (dyn_tag
== DT_NULL
)
470 else if (dyn_tag
== DT_DEBUG
)
472 dyn_ptr
= bfd_h_get_64 (exec_bfd
,
473 (bfd_byte
*) x_dynp
->d_un
.d_ptr
);
476 else if (dyn_tag
== DT_MIPS_RLD_MAP
)
479 int pbuf_size
= TYPE_LENGTH (builtin_type_void_data_ptr
);
481 pbuf
= alloca (pbuf_size
);
482 /* DT_MIPS_RLD_MAP contains a pointer to the address
483 of the dynamic link structure. */
484 dyn_ptr
= bfd_h_get_64 (exec_bfd
,
485 (bfd_byte
*) x_dynp
->d_un
.d_ptr
);
486 if (target_read_memory (dyn_ptr
, pbuf
, pbuf_size
))
488 return extract_typed_address (pbuf
, builtin_type_void_data_ptr
);
493 /* DT_DEBUG entry not found. */
501 locate_base -- locate the base address of dynamic linker structs
505 CORE_ADDR locate_base (void)
509 For both the SunOS and SVR4 shared library implementations, if the
510 inferior executable has been linked dynamically, there is a single
511 address somewhere in the inferior's data space which is the key to
512 locating all of the dynamic linker's runtime structures. This
513 address is the value of the debug base symbol. The job of this
514 function is to find and return that address, or to return 0 if there
515 is no such address (the executable is statically linked for example).
517 For SunOS, the job is almost trivial, since the dynamic linker and
518 all of it's structures are statically linked to the executable at
519 link time. Thus the symbol for the address we are looking for has
520 already been added to the minimal symbol table for the executable's
521 objfile at the time the symbol file's symbols were read, and all we
522 have to do is look it up there. Note that we explicitly do NOT want
523 to find the copies in the shared library.
525 The SVR4 version is a bit more complicated because the address
526 is contained somewhere in the dynamic info section. We have to go
527 to a lot more work to discover the address of the debug base symbol.
528 Because of this complexity, we cache the value we find and return that
529 value on subsequent invocations. Note there is no copy in the
530 executable symbol tables.
537 /* Check to see if we have a currently valid address, and if so, avoid
538 doing all this work again and just return the cached address. If
539 we have no cached address, try to locate it in the dynamic info
540 section for ELF executables. There's no point in doing any of this
541 though if we don't have some link map offsets to work with. */
543 if (debug_base
== 0 && svr4_have_link_map_offsets ())
546 && bfd_get_flavour (exec_bfd
) == bfd_target_elf_flavour
)
547 debug_base
= elf_locate_base ();
552 /* Find the first element in the inferior's dynamic link map, and
553 return its address in the inferior.
555 FIXME: Perhaps we should validate the info somehow, perhaps by
556 checking r_version for a known version number, or r_state for
560 solib_svr4_r_map (void)
562 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
564 return read_memory_typed_address (debug_base
+ lmo
->r_map_offset
,
565 builtin_type_void_data_ptr
);
568 /* Find the link map for the dynamic linker (if it is not in the
569 normal list of loaded shared objects). */
572 solib_svr4_r_ldsomap (void)
574 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
577 /* Check version, and return zero if `struct r_debug' doesn't have
578 the r_ldsomap member. */
579 version
= read_memory_unsigned_integer (debug_base
+ lmo
->r_version_offset
,
580 lmo
->r_version_size
);
581 if (version
< 2 || lmo
->r_ldsomap_offset
== -1)
584 return read_memory_typed_address (debug_base
+ lmo
->r_ldsomap_offset
,
585 builtin_type_void_data_ptr
);
592 open_symbol_file_object
596 void open_symbol_file_object (void *from_tty)
600 If no open symbol file, attempt to locate and open the main symbol
601 file. On SVR4 systems, this is the first link map entry. If its
602 name is here, we can open it. Useful when attaching to a process
603 without first loading its symbol file.
605 If FROM_TTYP dereferences to a non-zero integer, allow messages to
606 be printed. This parameter is a pointer rather than an int because
607 open_symbol_file_object() is called via catch_errors() and
608 catch_errors() requires a pointer argument. */
611 open_symbol_file_object (void *from_ttyp
)
613 CORE_ADDR lm
, l_name
;
616 int from_tty
= *(int *)from_ttyp
;
617 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
618 int l_name_size
= TYPE_LENGTH (builtin_type_void_data_ptr
);
619 gdb_byte
*l_name_buf
= xmalloc (l_name_size
);
620 struct cleanup
*cleanups
= make_cleanup (xfree
, l_name_buf
);
623 if (!query ("Attempt to reload symbols from process? "))
626 if ((debug_base
= locate_base ()) == 0)
627 return 0; /* failed somehow... */
629 /* First link map member should be the executable. */
630 lm
= solib_svr4_r_map ();
632 return 0; /* failed somehow... */
634 /* Read address of name from target memory to GDB. */
635 read_memory (lm
+ lmo
->l_name_offset
, l_name_buf
, l_name_size
);
637 /* Convert the address to host format. */
638 l_name
= extract_typed_address (l_name_buf
, builtin_type_void_data_ptr
);
640 /* Free l_name_buf. */
641 do_cleanups (cleanups
);
644 return 0; /* No filename. */
646 /* Now fetch the filename from target memory. */
647 target_read_string (l_name
, &filename
, SO_NAME_MAX_PATH_SIZE
- 1, &errcode
);
651 warning (_("failed to read exec filename from attached file: %s"),
652 safe_strerror (errcode
));
656 make_cleanup (xfree
, filename
);
657 /* Have a pathname: read the symbol file. */
658 symbol_file_add_main (filename
, from_tty
);
663 /* If no shared library information is available from the dynamic
664 linker, build a fallback list from other sources. */
666 static struct so_list
*
667 svr4_default_sos (void)
669 struct so_list
*head
= NULL
;
670 struct so_list
**link_ptr
= &head
;
672 if (debug_loader_offset_p
)
674 struct so_list
*new = XZALLOC (struct so_list
);
676 new->lm_info
= xmalloc (sizeof (struct lm_info
));
678 /* Nothing will ever check the cached copy of the link
679 map if we set l_addr. */
680 new->lm_info
->l_addr
= debug_loader_offset
;
681 new->lm_info
->lm
= NULL
;
683 strncpy (new->so_name
, debug_loader_name
, SO_NAME_MAX_PATH_SIZE
- 1);
684 new->so_name
[SO_NAME_MAX_PATH_SIZE
- 1] = '\0';
685 strcpy (new->so_original_name
, new->so_name
);
688 link_ptr
= &new->next
;
696 current_sos -- build a list of currently loaded shared objects
700 struct so_list *current_sos ()
704 Build a list of `struct so_list' objects describing the shared
705 objects currently loaded in the inferior. This list does not
706 include an entry for the main executable file.
708 Note that we only gather information directly available from the
709 inferior --- we don't examine any of the shared library files
710 themselves. The declaration of `struct so_list' says which fields
711 we provide values for. */
713 static struct so_list
*
714 svr4_current_sos (void)
717 struct so_list
*head
= 0;
718 struct so_list
**link_ptr
= &head
;
719 CORE_ADDR ldsomap
= 0;
721 /* Make sure we've looked up the inferior's dynamic linker's base
725 debug_base
= locate_base ();
727 /* If we can't find the dynamic linker's base structure, this
728 must not be a dynamically linked executable. Hmm. */
730 return svr4_default_sos ();
733 /* Walk the inferior's link map list, and build our list of
734 `struct so_list' nodes. */
735 lm
= solib_svr4_r_map ();
739 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
740 struct so_list
*new = XZALLOC (struct so_list
);
741 struct cleanup
*old_chain
= make_cleanup (xfree
, new);
743 new->lm_info
= xmalloc (sizeof (struct lm_info
));
744 make_cleanup (xfree
, new->lm_info
);
746 new->lm_info
->l_addr
= (CORE_ADDR
)-1;
747 new->lm_info
->lm
= xzalloc (lmo
->link_map_size
);
748 make_cleanup (xfree
, new->lm_info
->lm
);
750 read_memory (lm
, new->lm_info
->lm
, lmo
->link_map_size
);
754 /* For SVR4 versions, the first entry in the link map is for the
755 inferior executable, so we must ignore it. For some versions of
756 SVR4, it has no name. For others (Solaris 2.3 for example), it
757 does have a name, so we can no longer use a missing name to
758 decide when to ignore it. */
759 if (IGNORE_FIRST_LINK_MAP_ENTRY (new) && ldsomap
== 0)
766 /* Extract this shared object's name. */
767 target_read_string (LM_NAME (new), &buffer
,
768 SO_NAME_MAX_PATH_SIZE
- 1, &errcode
);
770 warning (_("Can't read pathname for load map: %s."),
771 safe_strerror (errcode
));
774 strncpy (new->so_name
, buffer
, SO_NAME_MAX_PATH_SIZE
- 1);
775 new->so_name
[SO_NAME_MAX_PATH_SIZE
- 1] = '\0';
777 strcpy (new->so_original_name
, new->so_name
);
780 /* If this entry has no name, or its name matches the name
781 for the main executable, don't include it in the list. */
782 if (! new->so_name
[0]
783 || match_main (new->so_name
))
789 link_ptr
= &new->next
;
793 /* On Solaris, the dynamic linker is not in the normal list of
794 shared objects, so make sure we pick it up too. Having
795 symbol information for the dynamic linker is quite crucial
796 for skipping dynamic linker resolver code. */
797 if (lm
== 0 && ldsomap
== 0)
798 lm
= ldsomap
= solib_svr4_r_ldsomap ();
800 discard_cleanups (old_chain
);
804 return svr4_default_sos ();
809 /* Get the address of the link_map for a given OBJFILE. Loop through
810 the link maps, and return the address of the one corresponding to
811 the given objfile. Note that this function takes into account that
812 objfile can be the main executable, not just a shared library. The
813 main executable has always an empty name field in the linkmap. */
816 svr4_fetch_objfile_link_map (struct objfile
*objfile
)
820 if ((debug_base
= locate_base ()) == 0)
821 return 0; /* failed somehow... */
823 /* Position ourselves on the first link map. */
824 lm
= solib_svr4_r_map ();
827 /* Get info on the layout of the r_debug and link_map structures. */
828 struct link_map_offsets
*lmo
= svr4_fetch_link_map_offsets ();
831 struct lm_info objfile_lm_info
;
832 struct cleanup
*old_chain
;
833 CORE_ADDR name_address
;
834 int l_name_size
= TYPE_LENGTH (builtin_type_void_data_ptr
);
835 gdb_byte
*l_name_buf
= xmalloc (l_name_size
);
836 old_chain
= make_cleanup (xfree
, l_name_buf
);
838 /* Set up the buffer to contain the portion of the link_map
839 structure that gdb cares about. Note that this is not the
840 whole link_map structure. */
841 objfile_lm_info
.lm
= xzalloc (lmo
->link_map_size
);
842 make_cleanup (xfree
, objfile_lm_info
.lm
);
844 /* Read the link map into our internal structure. */
845 read_memory (lm
, objfile_lm_info
.lm
, lmo
->link_map_size
);
847 /* Read address of name from target memory to GDB. */
848 read_memory (lm
+ lmo
->l_name_offset
, l_name_buf
, l_name_size
);
850 /* Extract this object's name. */
851 name_address
= extract_typed_address (l_name_buf
,
852 builtin_type_void_data_ptr
);
853 target_read_string (name_address
, &buffer
,
854 SO_NAME_MAX_PATH_SIZE
- 1, &errcode
);
855 make_cleanup (xfree
, buffer
);
857 warning (_("Can't read pathname for load map: %s."),
858 safe_strerror (errcode
));
861 /* Is this the linkmap for the file we want? */
862 /* If the file is not a shared library and has no name,
863 we are sure it is the main executable, so we return that. */
864 if ((buffer
&& strcmp (buffer
, objfile
->name
) == 0)
865 || (!(objfile
->flags
& OBJF_SHARED
) && (strcmp (buffer
, "") == 0)))
867 do_cleanups (old_chain
);
871 /* Not the file we wanted, continue checking. */
872 lm
= extract_typed_address (objfile_lm_info
.lm
+ lmo
->l_next_offset
,
873 builtin_type_void_data_ptr
);
874 do_cleanups (old_chain
);
879 /* On some systems, the only way to recognize the link map entry for
880 the main executable file is by looking at its name. Return
881 non-zero iff SONAME matches one of the known main executable names. */
884 match_main (char *soname
)
888 for (mainp
= main_name_list
; *mainp
!= NULL
; mainp
++)
890 if (strcmp (soname
, *mainp
) == 0)
897 /* Return 1 if PC lies in the dynamic symbol resolution code of the
898 SVR4 run time loader. */
899 static CORE_ADDR interp_text_sect_low
;
900 static CORE_ADDR interp_text_sect_high
;
901 static CORE_ADDR interp_plt_sect_low
;
902 static CORE_ADDR interp_plt_sect_high
;
905 svr4_in_dynsym_resolve_code (CORE_ADDR pc
)
907 return ((pc
>= interp_text_sect_low
&& pc
< interp_text_sect_high
)
908 || (pc
>= interp_plt_sect_low
&& pc
< interp_plt_sect_high
)
909 || in_plt_section (pc
, NULL
));
912 /* Given an executable's ABFD and target, compute the entry-point
916 exec_entry_point (struct bfd
*abfd
, struct target_ops
*targ
)
918 /* KevinB wrote ... for most targets, the address returned by
919 bfd_get_start_address() is the entry point for the start
920 function. But, for some targets, bfd_get_start_address() returns
921 the address of a function descriptor from which the entry point
922 address may be extracted. This address is extracted by
923 gdbarch_convert_from_func_ptr_addr(). The method
924 gdbarch_convert_from_func_ptr_addr() is the merely the identify
925 function for targets which don't use function descriptors. */
926 return gdbarch_convert_from_func_ptr_addr (current_gdbarch
,
927 bfd_get_start_address (abfd
),
935 enable_break -- arrange for dynamic linker to hit breakpoint
939 int enable_break (void)
943 Both the SunOS and the SVR4 dynamic linkers have, as part of their
944 debugger interface, support for arranging for the inferior to hit
945 a breakpoint after mapping in the shared libraries. This function
946 enables that breakpoint.
948 For SunOS, there is a special flag location (in_debugger) which we
949 set to 1. When the dynamic linker sees this flag set, it will set
950 a breakpoint at a location known only to itself, after saving the
951 original contents of that place and the breakpoint address itself,
952 in it's own internal structures. When we resume the inferior, it
953 will eventually take a SIGTRAP when it runs into the breakpoint.
954 We handle this (in a different place) by restoring the contents of
955 the breakpointed location (which is only known after it stops),
956 chasing around to locate the shared libraries that have been
957 loaded, then resuming.
959 For SVR4, the debugger interface structure contains a member (r_brk)
960 which is statically initialized at the time the shared library is
961 built, to the offset of a function (_r_debug_state) which is guaran-
962 teed to be called once before mapping in a library, and again when
963 the mapping is complete. At the time we are examining this member,
964 it contains only the unrelocated offset of the function, so we have
965 to do our own relocation. Later, when the dynamic linker actually
966 runs, it relocates r_brk to be the actual address of _r_debug_state().
968 The debugger interface structure also contains an enumeration which
969 is set to either RT_ADD or RT_DELETE prior to changing the mapping,
970 depending upon whether or not the library is being mapped or unmapped,
971 and then set to RT_CONSISTENT after the library is mapped/unmapped.
977 #ifdef BKPT_AT_SYMBOL
979 struct minimal_symbol
*msymbol
;
981 asection
*interp_sect
;
983 /* First, remove all the solib event breakpoints. Their addresses
984 may have changed since the last time we ran the program. */
985 remove_solib_event_breakpoints ();
987 interp_text_sect_low
= interp_text_sect_high
= 0;
988 interp_plt_sect_low
= interp_plt_sect_high
= 0;
990 /* Find the .interp section; if not found, warn the user and drop
991 into the old breakpoint at symbol code. */
992 interp_sect
= bfd_get_section_by_name (exec_bfd
, ".interp");
995 unsigned int interp_sect_size
;
997 CORE_ADDR load_addr
= 0;
998 int load_addr_found
= 0;
1000 bfd
*tmp_bfd
= NULL
;
1001 struct target_ops
*tmp_bfd_target
;
1003 char *tmp_pathname
= NULL
;
1004 CORE_ADDR sym_addr
= 0;
1006 /* Read the contents of the .interp section into a local buffer;
1007 the contents specify the dynamic linker this program uses. */
1008 interp_sect_size
= bfd_section_size (exec_bfd
, interp_sect
);
1009 buf
= alloca (interp_sect_size
);
1010 bfd_get_section_contents (exec_bfd
, interp_sect
,
1011 buf
, 0, interp_sect_size
);
1013 /* Now we need to figure out where the dynamic linker was
1014 loaded so that we can load its symbols and place a breakpoint
1015 in the dynamic linker itself.
1017 This address is stored on the stack. However, I've been unable
1018 to find any magic formula to find it for Solaris (appears to
1019 be trivial on GNU/Linux). Therefore, we have to try an alternate
1020 mechanism to find the dynamic linker's base address. */
1022 /* TODO drow/2006-09-12: This is somewhat fragile, because it
1023 relies on read_pc. On both Solaris and GNU/Linux we can use
1024 the AT_BASE auxilliary entry, which GDB now knows how to
1025 access, to find the base address. */
1027 tmp_fd
= solib_open (buf
, &tmp_pathname
);
1029 tmp_bfd
= bfd_fopen (tmp_pathname
, gnutarget
, FOPEN_RB
, tmp_fd
);
1031 if (tmp_bfd
== NULL
)
1032 goto bkpt_at_symbol
;
1034 /* Make sure the dynamic linker's really a useful object. */
1035 if (!bfd_check_format (tmp_bfd
, bfd_object
))
1037 warning (_("Unable to grok dynamic linker %s as an object file"), buf
);
1038 bfd_close (tmp_bfd
);
1039 goto bkpt_at_symbol
;
1042 /* Now convert the TMP_BFD into a target. That way target, as
1043 well as BFD operations can be used. Note that closing the
1044 target will also close the underlying bfd. */
1045 tmp_bfd_target
= target_bfd_reopen (tmp_bfd
);
1047 /* On a running target, we can get the dynamic linker's base
1048 address from the shared library table. */
1049 solib_add (NULL
, 0, NULL
, auto_solib_add
);
1050 so
= master_so_list ();
1053 if (strcmp (buf
, so
->so_original_name
) == 0)
1055 load_addr_found
= 1;
1056 load_addr
= LM_ADDR_CHECK (so
, tmp_bfd
);
1062 /* Otherwise we find the dynamic linker's base address by examining
1063 the current pc (which should point at the entry point for the
1064 dynamic linker) and subtracting the offset of the entry point. */
1065 if (!load_addr_found
)
1067 load_addr
= (read_pc ()
1068 - exec_entry_point (tmp_bfd
, tmp_bfd_target
));
1069 debug_loader_name
= xstrdup (buf
);
1070 debug_loader_offset_p
= 1;
1071 debug_loader_offset
= load_addr
;
1072 solib_add (NULL
, 0, NULL
, auto_solib_add
);
1075 /* Record the relocated start and end address of the dynamic linker
1076 text and plt section for svr4_in_dynsym_resolve_code. */
1077 interp_sect
= bfd_get_section_by_name (tmp_bfd
, ".text");
1080 interp_text_sect_low
=
1081 bfd_section_vma (tmp_bfd
, interp_sect
) + load_addr
;
1082 interp_text_sect_high
=
1083 interp_text_sect_low
+ bfd_section_size (tmp_bfd
, interp_sect
);
1085 interp_sect
= bfd_get_section_by_name (tmp_bfd
, ".plt");
1088 interp_plt_sect_low
=
1089 bfd_section_vma (tmp_bfd
, interp_sect
) + load_addr
;
1090 interp_plt_sect_high
=
1091 interp_plt_sect_low
+ bfd_section_size (tmp_bfd
, interp_sect
);
1094 /* Now try to set a breakpoint in the dynamic linker. */
1095 for (bkpt_namep
= solib_break_names
; *bkpt_namep
!= NULL
; bkpt_namep
++)
1097 /* On ABI's that use function descriptors, there are usually
1098 two linker symbols associated with each C function: one
1099 pointing at the actual entry point of the machine code,
1100 and one pointing at the function's descriptor. The
1101 latter symbol has the same name as the C function.
1103 What we're looking for here is the machine code entry
1104 point, so we are only interested in symbols in code
1106 sym_addr
= bfd_lookup_symbol (tmp_bfd
, *bkpt_namep
, SEC_CODE
);
1111 /* We're done with both the temporary bfd and target. Remember,
1112 closing the target closes the underlying bfd. */
1113 target_close (tmp_bfd_target
, 0);
1117 create_solib_event_breakpoint (load_addr
+ sym_addr
);
1121 /* For whatever reason we couldn't set a breakpoint in the dynamic
1122 linker. Warn and drop into the old code. */
1124 warning (_("Unable to find dynamic linker breakpoint function.\n"
1125 "GDB will be unable to debug shared library initializers\n"
1126 "and track explicitly loaded dynamic code."));
1129 /* Scan through the lists of symbols, trying to look up the symbol and
1130 set a breakpoint there. Terminate loop when we/if we succeed. */
1132 for (bkpt_namep
= solib_break_names
; *bkpt_namep
!= NULL
; bkpt_namep
++)
1134 msymbol
= lookup_minimal_symbol (*bkpt_namep
, NULL
, symfile_objfile
);
1135 if ((msymbol
!= NULL
) && (SYMBOL_VALUE_ADDRESS (msymbol
) != 0))
1137 create_solib_event_breakpoint (SYMBOL_VALUE_ADDRESS (msymbol
));
1142 for (bkpt_namep
= bkpt_names
; *bkpt_namep
!= NULL
; bkpt_namep
++)
1144 msymbol
= lookup_minimal_symbol (*bkpt_namep
, NULL
, symfile_objfile
);
1145 if ((msymbol
!= NULL
) && (SYMBOL_VALUE_ADDRESS (msymbol
) != 0))
1147 create_solib_event_breakpoint (SYMBOL_VALUE_ADDRESS (msymbol
));
1151 #endif /* BKPT_AT_SYMBOL */
1160 special_symbol_handling -- additional shared library symbol handling
1164 void special_symbol_handling ()
1168 Once the symbols from a shared object have been loaded in the usual
1169 way, we are called to do any system specific symbol handling that
1172 For SunOS4, this consisted of grunging around in the dynamic
1173 linkers structures to find symbol definitions for "common" symbols
1174 and adding them to the minimal symbol table for the runtime common
1177 However, for SVR4, there's nothing to do.
1182 svr4_special_symbol_handling (void)
1186 /* Relocate the main executable. This function should be called upon
1187 stopping the inferior process at the entry point to the program.
1188 The entry point from BFD is compared to the PC and if they are
1189 different, the main executable is relocated by the proper amount.
1191 As written it will only attempt to relocate executables which
1192 lack interpreter sections. It seems likely that only dynamic
1193 linker executables will get relocated, though it should work
1194 properly for a position-independent static executable as well. */
1197 svr4_relocate_main_executable (void)
1199 asection
*interp_sect
;
1200 CORE_ADDR pc
= read_pc ();
1202 /* Decide if the objfile needs to be relocated. As indicated above,
1203 we will only be here when execution is stopped at the beginning
1204 of the program. Relocation is necessary if the address at which
1205 we are presently stopped differs from the start address stored in
1206 the executable AND there's no interpreter section. The condition
1207 regarding the interpreter section is very important because if
1208 there *is* an interpreter section, execution will begin there
1209 instead. When there is an interpreter section, the start address
1210 is (presumably) used by the interpreter at some point to start
1211 execution of the program.
1213 If there is an interpreter, it is normal for it to be set to an
1214 arbitrary address at the outset. The job of finding it is
1215 handled in enable_break().
1217 So, to summarize, relocations are necessary when there is no
1218 interpreter section and the start address obtained from the
1219 executable is different from the address at which GDB is
1222 [ The astute reader will note that we also test to make sure that
1223 the executable in question has the DYNAMIC flag set. It is my
1224 opinion that this test is unnecessary (undesirable even). It
1225 was added to avoid inadvertent relocation of an executable
1226 whose e_type member in the ELF header is not ET_DYN. There may
1227 be a time in the future when it is desirable to do relocations
1228 on other types of files as well in which case this condition
1229 should either be removed or modified to accomodate the new file
1230 type. (E.g, an ET_EXEC executable which has been built to be
1231 position-independent could safely be relocated by the OS if
1232 desired. It is true that this violates the ABI, but the ABI
1233 has been known to be bent from time to time.) - Kevin, Nov 2000. ]
1236 interp_sect
= bfd_get_section_by_name (exec_bfd
, ".interp");
1237 if (interp_sect
== NULL
1238 && (bfd_get_file_flags (exec_bfd
) & DYNAMIC
) != 0
1239 && (exec_entry_point (exec_bfd
, &exec_ops
) != pc
))
1241 struct cleanup
*old_chain
;
1242 struct section_offsets
*new_offsets
;
1244 CORE_ADDR displacement
;
1246 /* It is necessary to relocate the objfile. The amount to
1247 relocate by is simply the address at which we are stopped
1248 minus the starting address from the executable.
1250 We relocate all of the sections by the same amount. This
1251 behavior is mandated by recent editions of the System V ABI.
1252 According to the System V Application Binary Interface,
1253 Edition 4.1, page 5-5:
1255 ... Though the system chooses virtual addresses for
1256 individual processes, it maintains the segments' relative
1257 positions. Because position-independent code uses relative
1258 addressesing between segments, the difference between
1259 virtual addresses in memory must match the difference
1260 between virtual addresses in the file. The difference
1261 between the virtual address of any segment in memory and
1262 the corresponding virtual address in the file is thus a
1263 single constant value for any one executable or shared
1264 object in a given process. This difference is the base
1265 address. One use of the base address is to relocate the
1266 memory image of the program during dynamic linking.
1268 The same language also appears in Edition 4.0 of the System V
1269 ABI and is left unspecified in some of the earlier editions. */
1271 displacement
= pc
- exec_entry_point (exec_bfd
, &exec_ops
);
1274 new_offsets
= xcalloc (symfile_objfile
->num_sections
,
1275 sizeof (struct section_offsets
));
1276 old_chain
= make_cleanup (xfree
, new_offsets
);
1278 for (i
= 0; i
< symfile_objfile
->num_sections
; i
++)
1280 if (displacement
!= ANOFFSET (symfile_objfile
->section_offsets
, i
))
1282 new_offsets
->offsets
[i
] = displacement
;
1286 objfile_relocate (symfile_objfile
, new_offsets
);
1288 do_cleanups (old_chain
);
1296 svr4_solib_create_inferior_hook -- shared library startup support
1300 void svr4_solib_create_inferior_hook ()
1304 When gdb starts up the inferior, it nurses it along (through the
1305 shell) until it is ready to execute it's first instruction. At this
1306 point, this function gets called via expansion of the macro
1307 SOLIB_CREATE_INFERIOR_HOOK.
1309 For SunOS executables, this first instruction is typically the
1310 one at "_start", or a similar text label, regardless of whether
1311 the executable is statically or dynamically linked. The runtime
1312 startup code takes care of dynamically linking in any shared
1313 libraries, once gdb allows the inferior to continue.
1315 For SVR4 executables, this first instruction is either the first
1316 instruction in the dynamic linker (for dynamically linked
1317 executables) or the instruction at "start" for statically linked
1318 executables. For dynamically linked executables, the system
1319 first exec's /lib/libc.so.N, which contains the dynamic linker,
1320 and starts it running. The dynamic linker maps in any needed
1321 shared libraries, maps in the actual user executable, and then
1322 jumps to "start" in the user executable.
1324 For both SunOS shared libraries, and SVR4 shared libraries, we
1325 can arrange to cooperate with the dynamic linker to discover the
1326 names of shared libraries that are dynamically linked, and the
1327 base addresses to which they are linked.
1329 This function is responsible for discovering those names and
1330 addresses, and saving sufficient information about them to allow
1331 their symbols to be read at a later time.
1335 Between enable_break() and disable_break(), this code does not
1336 properly handle hitting breakpoints which the user might have
1337 set in the startup code or in the dynamic linker itself. Proper
1338 handling will probably have to wait until the implementation is
1339 changed to use the "breakpoint handler function" method.
1341 Also, what if child has exit()ed? Must exit loop somehow.
1345 svr4_solib_create_inferior_hook (void)
1347 /* Relocate the main executable if necessary. */
1348 svr4_relocate_main_executable ();
1350 if (!svr4_have_link_map_offsets ())
1353 if (!enable_break ())
1356 #if defined(_SCO_DS)
1357 /* SCO needs the loop below, other systems should be using the
1358 special shared library breakpoints and the shared library breakpoint
1361 Now run the target. It will eventually hit the breakpoint, at
1362 which point all of the libraries will have been mapped in and we
1363 can go groveling around in the dynamic linker structures to find
1364 out what we need to know about them. */
1366 clear_proceed_status ();
1367 stop_soon
= STOP_QUIETLY
;
1368 stop_signal
= TARGET_SIGNAL_0
;
1371 target_resume (pid_to_ptid (-1), 0, stop_signal
);
1372 wait_for_inferior ();
1374 while (stop_signal
!= TARGET_SIGNAL_TRAP
);
1375 stop_soon
= NO_STOP_QUIETLY
;
1376 #endif /* defined(_SCO_DS) */
1380 svr4_clear_solib (void)
1383 debug_loader_offset_p
= 0;
1384 debug_loader_offset
= 0;
1385 xfree (debug_loader_name
);
1386 debug_loader_name
= NULL
;
1390 svr4_free_so (struct so_list
*so
)
1392 xfree (so
->lm_info
->lm
);
1393 xfree (so
->lm_info
);
1397 /* Clear any bits of ADDR that wouldn't fit in a target-format
1398 data pointer. "Data pointer" here refers to whatever sort of
1399 address the dynamic linker uses to manage its sections. At the
1400 moment, we don't support shared libraries on any processors where
1401 code and data pointers are different sizes.
1403 This isn't really the right solution. What we really need here is
1404 a way to do arithmetic on CORE_ADDR values that respects the
1405 natural pointer/address correspondence. (For example, on the MIPS,
1406 converting a 32-bit pointer to a 64-bit CORE_ADDR requires you to
1407 sign-extend the value. There, simply truncating the bits above
1408 TARGET_PTR_BIT, as we do below, is no good.) This should probably
1409 be a new gdbarch method or something. */
1411 svr4_truncate_ptr (CORE_ADDR addr
)
1413 if (TARGET_PTR_BIT
== sizeof (CORE_ADDR
) * 8)
1414 /* We don't need to truncate anything, and the bit twiddling below
1415 will fail due to overflow problems. */
1418 return addr
& (((CORE_ADDR
) 1 << TARGET_PTR_BIT
) - 1);
1423 svr4_relocate_section_addresses (struct so_list
*so
,
1424 struct section_table
*sec
)
1426 sec
->addr
= svr4_truncate_ptr (sec
->addr
+ LM_ADDR_CHECK (so
,
1428 sec
->endaddr
= svr4_truncate_ptr (sec
->endaddr
+ LM_ADDR_CHECK (so
,
1433 /* Architecture-specific operations. */
1435 /* Per-architecture data key. */
1436 static struct gdbarch_data
*solib_svr4_data
;
1438 struct solib_svr4_ops
1440 /* Return a description of the layout of `struct link_map'. */
1441 struct link_map_offsets
*(*fetch_link_map_offsets
)(void);
1444 /* Return a default for the architecture-specific operations. */
1447 solib_svr4_init (struct obstack
*obstack
)
1449 struct solib_svr4_ops
*ops
;
1451 ops
= OBSTACK_ZALLOC (obstack
, struct solib_svr4_ops
);
1452 ops
->fetch_link_map_offsets
= legacy_svr4_fetch_link_map_offsets_hook
;
1456 /* Set the architecture-specific `struct link_map_offsets' fetcher for
1460 set_solib_svr4_fetch_link_map_offsets (struct gdbarch
*gdbarch
,
1461 struct link_map_offsets
*(*flmo
) (void))
1463 struct solib_svr4_ops
*ops
= gdbarch_data (gdbarch
, solib_svr4_data
);
1465 ops
->fetch_link_map_offsets
= flmo
;
1468 /* Fetch a link_map_offsets structure using the architecture-specific
1469 `struct link_map_offsets' fetcher. */
1471 static struct link_map_offsets
*
1472 svr4_fetch_link_map_offsets (void)
1474 struct solib_svr4_ops
*ops
= gdbarch_data (current_gdbarch
, solib_svr4_data
);
1476 gdb_assert (ops
->fetch_link_map_offsets
);
1477 return ops
->fetch_link_map_offsets ();
1480 /* Return 1 if a link map offset fetcher has been defined, 0 otherwise. */
1483 svr4_have_link_map_offsets (void)
1485 struct solib_svr4_ops
*ops
= gdbarch_data (current_gdbarch
, solib_svr4_data
);
1486 return (ops
->fetch_link_map_offsets
!= NULL
);
1490 /* Most OS'es that have SVR4-style ELF dynamic libraries define a
1491 `struct r_debug' and a `struct link_map' that are binary compatible
1492 with the origional SVR4 implementation. */
1494 /* Fetch (and possibly build) an appropriate `struct link_map_offsets'
1495 for an ILP32 SVR4 system. */
1497 struct link_map_offsets
*
1498 svr4_ilp32_fetch_link_map_offsets (void)
1500 static struct link_map_offsets lmo
;
1501 static struct link_map_offsets
*lmp
= NULL
;
1507 lmo
.r_version_offset
= 0;
1508 lmo
.r_version_size
= 4;
1509 lmo
.r_map_offset
= 4;
1510 lmo
.r_ldsomap_offset
= 20;
1512 /* Everything we need is in the first 20 bytes. */
1513 lmo
.link_map_size
= 20;
1514 lmo
.l_addr_offset
= 0;
1515 lmo
.l_name_offset
= 4;
1516 lmo
.l_ld_offset
= 8;
1517 lmo
.l_next_offset
= 12;
1518 lmo
.l_prev_offset
= 16;
1524 /* Fetch (and possibly build) an appropriate `struct link_map_offsets'
1525 for an LP64 SVR4 system. */
1527 struct link_map_offsets
*
1528 svr4_lp64_fetch_link_map_offsets (void)
1530 static struct link_map_offsets lmo
;
1531 static struct link_map_offsets
*lmp
= NULL
;
1537 lmo
.r_version_offset
= 0;
1538 lmo
.r_version_size
= 4;
1539 lmo
.r_map_offset
= 8;
1540 lmo
.r_ldsomap_offset
= 40;
1542 /* Everything we need is in the first 40 bytes. */
1543 lmo
.link_map_size
= 40;
1544 lmo
.l_addr_offset
= 0;
1545 lmo
.l_name_offset
= 8;
1546 lmo
.l_ld_offset
= 16;
1547 lmo
.l_next_offset
= 24;
1548 lmo
.l_prev_offset
= 32;
1555 struct target_so_ops svr4_so_ops
;
1557 extern initialize_file_ftype _initialize_svr4_solib
; /* -Wmissing-prototypes */
1560 _initialize_svr4_solib (void)
1562 solib_svr4_data
= gdbarch_data_register_pre_init (solib_svr4_init
);
1564 svr4_so_ops
.relocate_section_addresses
= svr4_relocate_section_addresses
;
1565 svr4_so_ops
.free_so
= svr4_free_so
;
1566 svr4_so_ops
.clear_solib
= svr4_clear_solib
;
1567 svr4_so_ops
.solib_create_inferior_hook
= svr4_solib_create_inferior_hook
;
1568 svr4_so_ops
.special_symbol_handling
= svr4_special_symbol_handling
;
1569 svr4_so_ops
.current_sos
= svr4_current_sos
;
1570 svr4_so_ops
.open_symbol_file_object
= open_symbol_file_object
;
1571 svr4_so_ops
.in_dynsym_resolve_code
= svr4_in_dynsym_resolve_code
;
1573 /* FIXME: Don't do this here. *_gdbarch_init() should set so_ops. */
1574 current_target_so_ops
= &svr4_so_ops
;