1 /* Handle SVR4 shared libraries for GDB, the GNU Debugger.
3 Copyright 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999,
5 Free Software Foundation, Inc.
7 This file is part of GDB.
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program; if not, write to the Free Software
21 Foundation, Inc., 59 Temple Place - Suite 330,
22 Boston, MA 02111-1307, USA. */
26 #include "elf/external.h"
27 #include "elf/common.h"
39 #include "solib-svr4.h"
41 #include "bfd-target.h"
44 #ifndef SVR4_FETCH_LINK_MAP_OFFSETS
45 #define SVR4_FETCH_LINK_MAP_OFFSETS() svr4_fetch_link_map_offsets ()
48 static struct link_map_offsets
*svr4_fetch_link_map_offsets (void);
49 static struct link_map_offsets
*legacy_fetch_link_map_offsets (void);
50 static int svr4_have_link_map_offsets (void);
52 /* fetch_link_map_offsets_gdbarch_data is a handle used to obtain the
53 architecture specific link map offsets fetching function. */
55 static struct gdbarch_data
*fetch_link_map_offsets_gdbarch_data
;
57 /* legacy_svr4_fetch_link_map_offsets_hook is a pointer to a function
58 which is used to fetch link map offsets. It will only be set
59 by solib-legacy.c, if at all. */
61 struct link_map_offsets
*(*legacy_svr4_fetch_link_map_offsets_hook
)(void) = 0;
63 /* Link map info to include in an allocated so_list entry */
67 /* Pointer to copy of link map from inferior. The type is char *
68 rather than void *, so that we may use byte offsets to find the
69 various fields without the need for a cast. */
73 /* On SVR4 systems, a list of symbols in the dynamic linker where
74 GDB can try to place a breakpoint to monitor shared library
77 If none of these symbols are found, or other errors occur, then
78 SVR4 systems will fall back to using a symbol as the "startup
79 mapping complete" breakpoint address. */
81 static char *solib_break_names
[] =
89 /* On the 64-bit PowerPC, the linker symbol with the same name as
90 the C function points to a function descriptor, not to the entry
91 point. The linker symbol whose name is the C function name
92 prefixed with a '.' points to the function's entry point. So
93 when we look through this table, we ignore symbols that point
94 into the data section (thus skipping the descriptor's symbol),
95 and eventually try this one, giving us the real entry point
102 #define BKPT_AT_SYMBOL 1
104 #if defined (BKPT_AT_SYMBOL)
105 static char *bkpt_names
[] =
107 #ifdef SOLIB_BKPT_NAME
108 SOLIB_BKPT_NAME
, /* Prefer configured name if it exists. */
117 static char *main_name_list
[] =
123 /* Macro to extract an address from a solib structure. When GDB is
124 configured for some 32-bit targets (e.g. Solaris 2.7 sparc), BFD is
125 configured to handle 64-bit targets, so CORE_ADDR is 64 bits. We
126 have to extract only the significant bits of addresses to get the
127 right address when accessing the core file BFD.
129 Assume that the address is unsigned. */
131 #define SOLIB_EXTRACT_ADDRESS(MEMBER) \
132 extract_unsigned_integer (&(MEMBER), sizeof (MEMBER))
134 /* local data declarations */
136 /* link map access functions */
139 LM_ADDR (struct so_list
*so
)
141 struct link_map_offsets
*lmo
= SVR4_FETCH_LINK_MAP_OFFSETS ();
143 return (CORE_ADDR
) extract_signed_integer (so
->lm_info
->lm
+ lmo
->l_addr_offset
,
148 LM_NEXT (struct so_list
*so
)
150 struct link_map_offsets
*lmo
= SVR4_FETCH_LINK_MAP_OFFSETS ();
152 /* Assume that the address is unsigned. */
153 return extract_unsigned_integer (so
->lm_info
->lm
+ lmo
->l_next_offset
,
158 LM_NAME (struct so_list
*so
)
160 struct link_map_offsets
*lmo
= SVR4_FETCH_LINK_MAP_OFFSETS ();
162 /* Assume that the address is unsigned. */
163 return extract_unsigned_integer (so
->lm_info
->lm
+ lmo
->l_name_offset
,
168 IGNORE_FIRST_LINK_MAP_ENTRY (struct so_list
*so
)
170 struct link_map_offsets
*lmo
= SVR4_FETCH_LINK_MAP_OFFSETS ();
172 /* Assume that the address is unsigned. */
173 return extract_unsigned_integer (so
->lm_info
->lm
+ lmo
->l_prev_offset
,
174 lmo
->l_prev_size
) == 0;
177 static CORE_ADDR debug_base
; /* Base of dynamic linker structures */
178 static CORE_ADDR breakpoint_addr
; /* Address where end bkpt is set */
180 /* Local function prototypes */
182 static int match_main (char *);
184 static CORE_ADDR
bfd_lookup_symbol (bfd
*, char *, flagword
);
190 bfd_lookup_symbol -- lookup the value for a specific symbol
194 CORE_ADDR bfd_lookup_symbol (bfd *abfd, char *symname, flagword sect_flags)
198 An expensive way to lookup the value of a single symbol for
199 bfd's that are only temporary anyway. This is used by the
200 shared library support to find the address of the debugger
201 interface structures in the shared library.
203 If SECT_FLAGS is non-zero, only match symbols in sections whose
204 flags include all those in SECT_FLAGS.
206 Note that 0 is specifically allowed as an error return (no
211 bfd_lookup_symbol (bfd
*abfd
, char *symname
, flagword sect_flags
)
215 asymbol
**symbol_table
;
216 unsigned int number_of_symbols
;
218 struct cleanup
*back_to
;
219 CORE_ADDR symaddr
= 0;
221 storage_needed
= bfd_get_symtab_upper_bound (abfd
);
223 if (storage_needed
> 0)
225 symbol_table
= (asymbol
**) xmalloc (storage_needed
);
226 back_to
= make_cleanup (xfree
, symbol_table
);
227 number_of_symbols
= bfd_canonicalize_symtab (abfd
, symbol_table
);
229 for (i
= 0; i
< number_of_symbols
; i
++)
231 sym
= *symbol_table
++;
232 if (strcmp (sym
->name
, symname
) == 0
233 && (sym
->section
->flags
& sect_flags
) == sect_flags
)
235 /* Bfd symbols are section relative. */
236 symaddr
= sym
->value
+ sym
->section
->vma
;
240 do_cleanups (back_to
);
246 /* On FreeBSD, the dynamic linker is stripped by default. So we'll
247 have to check the dynamic string table too. */
249 storage_needed
= bfd_get_dynamic_symtab_upper_bound (abfd
);
251 if (storage_needed
> 0)
253 symbol_table
= (asymbol
**) xmalloc (storage_needed
);
254 back_to
= make_cleanup (xfree
, symbol_table
);
255 number_of_symbols
= bfd_canonicalize_dynamic_symtab (abfd
, symbol_table
);
257 for (i
= 0; i
< number_of_symbols
; i
++)
259 sym
= *symbol_table
++;
261 if (strcmp (sym
->name
, symname
) == 0
262 && (sym
->section
->flags
& sect_flags
) == sect_flags
)
264 /* Bfd symbols are section relative. */
265 symaddr
= sym
->value
+ sym
->section
->vma
;
269 do_cleanups (back_to
);
275 #ifdef HANDLE_SVR4_EXEC_EMULATORS
278 Solaris BCP (the part of Solaris which allows it to run SunOS4
279 a.out files) throws in another wrinkle. Solaris does not fill
280 in the usual a.out link map structures when running BCP programs,
281 the only way to get at them is via groping around in the dynamic
283 The dynamic linker and it's structures are located in the shared
284 C library, which gets run as the executable's "interpreter" by
287 Note that we can assume nothing about the process state at the time
288 we need to find these structures. We may be stopped on the first
289 instruction of the interpreter (C shared library), the first
290 instruction of the executable itself, or somewhere else entirely
291 (if we attached to the process for example).
294 static char *debug_base_symbols
[] =
296 "r_debug", /* Solaris 2.3 */
297 "_r_debug", /* Solaris 2.1, 2.2 */
301 static int look_for_base (int, CORE_ADDR
);
307 look_for_base -- examine file for each mapped address segment
311 static int look_for_base (int fd, CORE_ADDR baseaddr)
315 This function is passed to proc_iterate_over_mappings, which
316 causes it to get called once for each mapped address space, with
317 an open file descriptor for the file mapped to that space, and the
318 base address of that mapped space.
320 Our job is to find the debug base symbol in the file that this
321 fd is open on, if it exists, and if so, initialize the dynamic
322 linker structure base address debug_base.
324 Note that this is a computationally expensive proposition, since
325 we basically have to open a bfd on every call, so we specifically
326 avoid opening the exec file.
330 look_for_base (int fd
, CORE_ADDR baseaddr
)
333 CORE_ADDR address
= 0;
336 /* If the fd is -1, then there is no file that corresponds to this
337 mapped memory segment, so skip it. Also, if the fd corresponds
338 to the exec file, skip it as well. */
342 && fdmatch (fileno ((FILE *) (exec_bfd
->iostream
)), fd
)))
347 /* Try to open whatever random file this fd corresponds to. Note that
348 we have no way currently to find the filename. Don't gripe about
349 any problems we might have, just fail. */
351 if ((interp_bfd
= bfd_fdopenr ("unnamed", gnutarget
, fd
)) == NULL
)
355 if (!bfd_check_format (interp_bfd
, bfd_object
))
357 /* FIXME-leak: on failure, might not free all memory associated with
359 bfd_close (interp_bfd
);
363 /* Now try to find our debug base symbol in this file, which we at
364 least know to be a valid ELF executable or shared library. */
366 for (symbolp
= debug_base_symbols
; *symbolp
!= NULL
; symbolp
++)
368 address
= bfd_lookup_symbol (interp_bfd
, *symbolp
, 0);
376 /* FIXME-leak: on failure, might not free all memory associated with
378 bfd_close (interp_bfd
);
382 /* Eureka! We found the symbol. But now we may need to relocate it
383 by the base address. If the symbol's value is less than the base
384 address of the shared library, then it hasn't yet been relocated
385 by the dynamic linker, and we have to do it ourself. FIXME: Note
386 that we make the assumption that the first segment that corresponds
387 to the shared library has the base address to which the library
390 if (address
< baseaddr
)
394 debug_base
= address
;
395 /* FIXME-leak: on failure, might not free all memory associated with
397 bfd_close (interp_bfd
);
400 #endif /* HANDLE_SVR4_EXEC_EMULATORS */
406 elf_locate_base -- locate the base address of dynamic linker structs
407 for SVR4 elf targets.
411 CORE_ADDR elf_locate_base (void)
415 For SVR4 elf targets the address of the dynamic linker's runtime
416 structure is contained within the dynamic info section in the
417 executable file. The dynamic section is also mapped into the
418 inferior address space. Because the runtime loader fills in the
419 real address before starting the inferior, we have to read in the
420 dynamic info section from the inferior address space.
421 If there are any errors while trying to find the address, we
422 silently return 0, otherwise the found address is returned.
427 elf_locate_base (void)
429 struct bfd_section
*dyninfo_sect
;
430 int dyninfo_sect_size
;
431 CORE_ADDR dyninfo_addr
;
436 /* Find the start address of the .dynamic section. */
437 dyninfo_sect
= bfd_get_section_by_name (exec_bfd
, ".dynamic");
438 if (dyninfo_sect
== NULL
)
440 dyninfo_addr
= bfd_section_vma (exec_bfd
, dyninfo_sect
);
442 /* Read in .dynamic section, silently ignore errors. */
443 dyninfo_sect_size
= bfd_section_size (exec_bfd
, dyninfo_sect
);
444 buf
= alloca (dyninfo_sect_size
);
445 if (target_read_memory (dyninfo_addr
, buf
, dyninfo_sect_size
))
448 /* Find the DT_DEBUG entry in the the .dynamic section.
449 For mips elf we look for DT_MIPS_RLD_MAP, mips elf apparently has
450 no DT_DEBUG entries. */
452 arch_size
= bfd_get_arch_size (exec_bfd
);
453 if (arch_size
== -1) /* failure */
458 for (bufend
= buf
+ dyninfo_sect_size
;
460 buf
+= sizeof (Elf32_External_Dyn
))
462 Elf32_External_Dyn
*x_dynp
= (Elf32_External_Dyn
*) buf
;
466 dyn_tag
= bfd_h_get_32 (exec_bfd
, (bfd_byte
*) x_dynp
->d_tag
);
467 if (dyn_tag
== DT_NULL
)
469 else if (dyn_tag
== DT_DEBUG
)
471 dyn_ptr
= bfd_h_get_32 (exec_bfd
,
472 (bfd_byte
*) x_dynp
->d_un
.d_ptr
);
475 else if (dyn_tag
== DT_MIPS_RLD_MAP
)
478 int pbuf_size
= TARGET_PTR_BIT
/ HOST_CHAR_BIT
;
480 pbuf
= alloca (pbuf_size
);
481 /* DT_MIPS_RLD_MAP contains a pointer to the address
482 of the dynamic link structure. */
483 dyn_ptr
= bfd_h_get_32 (exec_bfd
,
484 (bfd_byte
*) x_dynp
->d_un
.d_ptr
);
485 if (target_read_memory (dyn_ptr
, pbuf
, pbuf_size
))
487 return extract_unsigned_integer (pbuf
, pbuf_size
);
491 else /* 64-bit elf */
493 for (bufend
= buf
+ dyninfo_sect_size
;
495 buf
+= sizeof (Elf64_External_Dyn
))
497 Elf64_External_Dyn
*x_dynp
= (Elf64_External_Dyn
*) buf
;
501 dyn_tag
= bfd_h_get_64 (exec_bfd
, (bfd_byte
*) x_dynp
->d_tag
);
502 if (dyn_tag
== DT_NULL
)
504 else if (dyn_tag
== DT_DEBUG
)
506 dyn_ptr
= bfd_h_get_64 (exec_bfd
,
507 (bfd_byte
*) x_dynp
->d_un
.d_ptr
);
510 else if (dyn_tag
== DT_MIPS_RLD_MAP
)
513 int pbuf_size
= TARGET_PTR_BIT
/ HOST_CHAR_BIT
;
515 pbuf
= alloca (pbuf_size
);
516 /* DT_MIPS_RLD_MAP contains a pointer to the address
517 of the dynamic link structure. */
518 dyn_ptr
= bfd_h_get_64 (exec_bfd
,
519 (bfd_byte
*) x_dynp
->d_un
.d_ptr
);
520 if (target_read_memory (dyn_ptr
, pbuf
, pbuf_size
))
522 return extract_unsigned_integer (pbuf
, pbuf_size
);
527 /* DT_DEBUG entry not found. */
535 locate_base -- locate the base address of dynamic linker structs
539 CORE_ADDR locate_base (void)
543 For both the SunOS and SVR4 shared library implementations, if the
544 inferior executable has been linked dynamically, there is a single
545 address somewhere in the inferior's data space which is the key to
546 locating all of the dynamic linker's runtime structures. This
547 address is the value of the debug base symbol. The job of this
548 function is to find and return that address, or to return 0 if there
549 is no such address (the executable is statically linked for example).
551 For SunOS, the job is almost trivial, since the dynamic linker and
552 all of it's structures are statically linked to the executable at
553 link time. Thus the symbol for the address we are looking for has
554 already been added to the minimal symbol table for the executable's
555 objfile at the time the symbol file's symbols were read, and all we
556 have to do is look it up there. Note that we explicitly do NOT want
557 to find the copies in the shared library.
559 The SVR4 version is a bit more complicated because the address
560 is contained somewhere in the dynamic info section. We have to go
561 to a lot more work to discover the address of the debug base symbol.
562 Because of this complexity, we cache the value we find and return that
563 value on subsequent invocations. Note there is no copy in the
564 executable symbol tables.
571 /* Check to see if we have a currently valid address, and if so, avoid
572 doing all this work again and just return the cached address. If
573 we have no cached address, try to locate it in the dynamic info
574 section for ELF executables. There's no point in doing any of this
575 though if we don't have some link map offsets to work with. */
577 if (debug_base
== 0 && svr4_have_link_map_offsets ())
580 && bfd_get_flavour (exec_bfd
) == bfd_target_elf_flavour
)
581 debug_base
= elf_locate_base ();
582 #ifdef HANDLE_SVR4_EXEC_EMULATORS
583 /* Try it the hard way for emulated executables. */
584 else if (!ptid_equal (inferior_ptid
, null_ptid
) && target_has_execution
)
585 proc_iterate_over_mappings (look_for_base
);
595 first_link_map_member -- locate first member in dynamic linker's map
599 static CORE_ADDR first_link_map_member (void)
603 Find the first element in the inferior's dynamic link map, and
604 return its address in the inferior. This function doesn't copy the
605 link map entry itself into our address space; current_sos actually
609 first_link_map_member (void)
612 struct link_map_offsets
*lmo
= SVR4_FETCH_LINK_MAP_OFFSETS ();
613 char *r_map_buf
= xmalloc (lmo
->r_map_size
);
614 struct cleanup
*cleanups
= make_cleanup (xfree
, r_map_buf
);
616 read_memory (debug_base
+ lmo
->r_map_offset
, r_map_buf
, lmo
->r_map_size
);
618 /* Assume that the address is unsigned. */
619 lm
= extract_unsigned_integer (r_map_buf
, lmo
->r_map_size
);
621 /* FIXME: Perhaps we should validate the info somehow, perhaps by
622 checking r_version for a known version number, or r_state for
625 do_cleanups (cleanups
);
634 open_symbol_file_object
638 void open_symbol_file_object (void *from_tty)
642 If no open symbol file, attempt to locate and open the main symbol
643 file. On SVR4 systems, this is the first link map entry. If its
644 name is here, we can open it. Useful when attaching to a process
645 without first loading its symbol file.
647 If FROM_TTYP dereferences to a non-zero integer, allow messages to
648 be printed. This parameter is a pointer rather than an int because
649 open_symbol_file_object() is called via catch_errors() and
650 catch_errors() requires a pointer argument. */
653 open_symbol_file_object (void *from_ttyp
)
655 CORE_ADDR lm
, l_name
;
658 int from_tty
= *(int *)from_ttyp
;
659 struct link_map_offsets
*lmo
= SVR4_FETCH_LINK_MAP_OFFSETS ();
660 char *l_name_buf
= xmalloc (lmo
->l_name_size
);
661 struct cleanup
*cleanups
= make_cleanup (xfree
, l_name_buf
);
664 if (!query ("Attempt to reload symbols from process? "))
667 if ((debug_base
= locate_base ()) == 0)
668 return 0; /* failed somehow... */
670 /* First link map member should be the executable. */
671 if ((lm
= first_link_map_member ()) == 0)
672 return 0; /* failed somehow... */
674 /* Read address of name from target memory to GDB. */
675 read_memory (lm
+ lmo
->l_name_offset
, l_name_buf
, lmo
->l_name_size
);
677 /* Convert the address to host format. Assume that the address is
679 l_name
= extract_unsigned_integer (l_name_buf
, lmo
->l_name_size
);
681 /* Free l_name_buf. */
682 do_cleanups (cleanups
);
685 return 0; /* No filename. */
687 /* Now fetch the filename from target memory. */
688 target_read_string (l_name
, &filename
, SO_NAME_MAX_PATH_SIZE
- 1, &errcode
);
692 warning ("failed to read exec filename from attached file: %s",
693 safe_strerror (errcode
));
697 make_cleanup (xfree
, filename
);
698 /* Have a pathname: read the symbol file. */
699 symbol_file_add_main (filename
, from_tty
);
706 current_sos -- build a list of currently loaded shared objects
710 struct so_list *current_sos ()
714 Build a list of `struct so_list' objects describing the shared
715 objects currently loaded in the inferior. This list does not
716 include an entry for the main executable file.
718 Note that we only gather information directly available from the
719 inferior --- we don't examine any of the shared library files
720 themselves. The declaration of `struct so_list' says which fields
721 we provide values for. */
723 static struct so_list
*
724 svr4_current_sos (void)
727 struct so_list
*head
= 0;
728 struct so_list
**link_ptr
= &head
;
730 /* Make sure we've looked up the inferior's dynamic linker's base
734 debug_base
= locate_base ();
736 /* If we can't find the dynamic linker's base structure, this
737 must not be a dynamically linked executable. Hmm. */
742 /* Walk the inferior's link map list, and build our list of
743 `struct so_list' nodes. */
744 lm
= first_link_map_member ();
747 struct link_map_offsets
*lmo
= SVR4_FETCH_LINK_MAP_OFFSETS ();
749 = (struct so_list
*) xmalloc (sizeof (struct so_list
));
750 struct cleanup
*old_chain
= make_cleanup (xfree
, new);
752 memset (new, 0, sizeof (*new));
754 new->lm_info
= xmalloc (sizeof (struct lm_info
));
755 make_cleanup (xfree
, new->lm_info
);
757 new->lm_info
->lm
= xmalloc (lmo
->link_map_size
);
758 make_cleanup (xfree
, new->lm_info
->lm
);
759 memset (new->lm_info
->lm
, 0, lmo
->link_map_size
);
761 read_memory (lm
, new->lm_info
->lm
, lmo
->link_map_size
);
765 /* For SVR4 versions, the first entry in the link map is for the
766 inferior executable, so we must ignore it. For some versions of
767 SVR4, it has no name. For others (Solaris 2.3 for example), it
768 does have a name, so we can no longer use a missing name to
769 decide when to ignore it. */
770 if (IGNORE_FIRST_LINK_MAP_ENTRY (new))
777 /* Extract this shared object's name. */
778 target_read_string (LM_NAME (new), &buffer
,
779 SO_NAME_MAX_PATH_SIZE
- 1, &errcode
);
782 warning ("current_sos: Can't read pathname for load map: %s\n",
783 safe_strerror (errcode
));
787 strncpy (new->so_name
, buffer
, SO_NAME_MAX_PATH_SIZE
- 1);
788 new->so_name
[SO_NAME_MAX_PATH_SIZE
- 1] = '\0';
790 strcpy (new->so_original_name
, new->so_name
);
793 /* If this entry has no name, or its name matches the name
794 for the main executable, don't include it in the list. */
795 if (! new->so_name
[0]
796 || match_main (new->so_name
))
802 link_ptr
= &new->next
;
806 discard_cleanups (old_chain
);
812 /* Get the address of the link_map for a given OBJFILE. Loop through
813 the link maps, and return the address of the one corresponding to
814 the given objfile. Note that this function takes into account that
815 objfile can be the main executable, not just a shared library. The
816 main executable has always an empty name field in the linkmap. */
819 svr4_fetch_objfile_link_map (struct objfile
*objfile
)
823 if ((debug_base
= locate_base ()) == 0)
824 return 0; /* failed somehow... */
826 /* Position ourselves on the first link map. */
827 lm
= first_link_map_member ();
830 /* Get info on the layout of the r_debug and link_map structures. */
831 struct link_map_offsets
*lmo
= SVR4_FETCH_LINK_MAP_OFFSETS ();
834 struct lm_info objfile_lm_info
;
835 struct cleanup
*old_chain
;
836 CORE_ADDR name_address
;
837 char *l_name_buf
= xmalloc (lmo
->l_name_size
);
838 old_chain
= make_cleanup (xfree
, l_name_buf
);
840 /* Set up the buffer to contain the portion of the link_map
841 structure that gdb cares about. Note that this is not the
842 whole link_map structure. */
843 objfile_lm_info
.lm
= xmalloc (lmo
->link_map_size
);
844 make_cleanup (xfree
, objfile_lm_info
.lm
);
845 memset (objfile_lm_info
.lm
, 0, lmo
->link_map_size
);
847 /* Read the link map into our internal structure. */
848 read_memory (lm
, objfile_lm_info
.lm
, lmo
->link_map_size
);
850 /* Read address of name from target memory to GDB. */
851 read_memory (lm
+ lmo
->l_name_offset
, l_name_buf
, lmo
->l_name_size
);
853 /* Extract this object's name. Assume that the address is
855 name_address
= extract_unsigned_integer (l_name_buf
, lmo
->l_name_size
);
856 target_read_string (name_address
, &buffer
,
857 SO_NAME_MAX_PATH_SIZE
- 1, &errcode
);
858 make_cleanup (xfree
, buffer
);
861 warning ("svr4_fetch_objfile_link_map: Can't read pathname for load map: %s\n",
862 safe_strerror (errcode
));
866 /* Is this the linkmap for the file we want? */
867 /* If the file is not a shared library and has no name,
868 we are sure it is the main executable, so we return that. */
869 if ((buffer
&& strcmp (buffer
, objfile
->name
) == 0)
870 || (!(objfile
->flags
& OBJF_SHARED
) && (strcmp (buffer
, "") == 0)))
872 do_cleanups (old_chain
);
876 /* Not the file we wanted, continue checking. Assume that the
877 address is unsigned. */
878 lm
= extract_unsigned_integer (objfile_lm_info
.lm
+ lmo
->l_next_offset
,
880 do_cleanups (old_chain
);
885 /* On some systems, the only way to recognize the link map entry for
886 the main executable file is by looking at its name. Return
887 non-zero iff SONAME matches one of the known main executable names. */
890 match_main (char *soname
)
894 for (mainp
= main_name_list
; *mainp
!= NULL
; mainp
++)
896 if (strcmp (soname
, *mainp
) == 0)
903 /* Return 1 if PC lies in the dynamic symbol resolution code of the
904 SVR4 run time loader. */
905 static CORE_ADDR interp_text_sect_low
;
906 static CORE_ADDR interp_text_sect_high
;
907 static CORE_ADDR interp_plt_sect_low
;
908 static CORE_ADDR interp_plt_sect_high
;
911 svr4_in_dynsym_resolve_code (CORE_ADDR pc
)
913 return ((pc
>= interp_text_sect_low
&& pc
< interp_text_sect_high
)
914 || (pc
>= interp_plt_sect_low
&& pc
< interp_plt_sect_high
)
915 || in_plt_section (pc
, NULL
));
918 /* Given an executable's ABFD and target, compute the entry-point
922 exec_entry_point (struct bfd
*abfd
, struct target_ops
*targ
)
924 /* KevinB wrote ... for most targets, the address returned by
925 bfd_get_start_address() is the entry point for the start
926 function. But, for some targets, bfd_get_start_address() returns
927 the address of a function descriptor from which the entry point
928 address may be extracted. This address is extracted by
929 gdbarch_convert_from_func_ptr_addr(). The method
930 gdbarch_convert_from_func_ptr_addr() is the merely the identify
931 function for targets which don't use function descriptors. */
932 return gdbarch_convert_from_func_ptr_addr (current_gdbarch
,
933 bfd_get_start_address (abfd
),
941 enable_break -- arrange for dynamic linker to hit breakpoint
945 int enable_break (void)
949 Both the SunOS and the SVR4 dynamic linkers have, as part of their
950 debugger interface, support for arranging for the inferior to hit
951 a breakpoint after mapping in the shared libraries. This function
952 enables that breakpoint.
954 For SunOS, there is a special flag location (in_debugger) which we
955 set to 1. When the dynamic linker sees this flag set, it will set
956 a breakpoint at a location known only to itself, after saving the
957 original contents of that place and the breakpoint address itself,
958 in it's own internal structures. When we resume the inferior, it
959 will eventually take a SIGTRAP when it runs into the breakpoint.
960 We handle this (in a different place) by restoring the contents of
961 the breakpointed location (which is only known after it stops),
962 chasing around to locate the shared libraries that have been
963 loaded, then resuming.
965 For SVR4, the debugger interface structure contains a member (r_brk)
966 which is statically initialized at the time the shared library is
967 built, to the offset of a function (_r_debug_state) which is guaran-
968 teed to be called once before mapping in a library, and again when
969 the mapping is complete. At the time we are examining this member,
970 it contains only the unrelocated offset of the function, so we have
971 to do our own relocation. Later, when the dynamic linker actually
972 runs, it relocates r_brk to be the actual address of _r_debug_state().
974 The debugger interface structure also contains an enumeration which
975 is set to either RT_ADD or RT_DELETE prior to changing the mapping,
976 depending upon whether or not the library is being mapped or unmapped,
977 and then set to RT_CONSISTENT after the library is mapped/unmapped.
985 #ifdef BKPT_AT_SYMBOL
987 struct minimal_symbol
*msymbol
;
989 asection
*interp_sect
;
991 /* First, remove all the solib event breakpoints. Their addresses
992 may have changed since the last time we ran the program. */
993 remove_solib_event_breakpoints ();
995 interp_text_sect_low
= interp_text_sect_high
= 0;
996 interp_plt_sect_low
= interp_plt_sect_high
= 0;
998 /* Find the .interp section; if not found, warn the user and drop
999 into the old breakpoint at symbol code. */
1000 interp_sect
= bfd_get_section_by_name (exec_bfd
, ".interp");
1003 unsigned int interp_sect_size
;
1005 CORE_ADDR load_addr
= 0;
1006 int load_addr_found
= 0;
1007 struct so_list
*inferior_sos
;
1008 bfd
*tmp_bfd
= NULL
;
1009 struct target_ops
*tmp_bfd_target
;
1011 char *tmp_pathname
= NULL
;
1012 CORE_ADDR sym_addr
= 0;
1014 /* Read the contents of the .interp section into a local buffer;
1015 the contents specify the dynamic linker this program uses. */
1016 interp_sect_size
= bfd_section_size (exec_bfd
, interp_sect
);
1017 buf
= alloca (interp_sect_size
);
1018 bfd_get_section_contents (exec_bfd
, interp_sect
,
1019 buf
, 0, interp_sect_size
);
1021 /* Now we need to figure out where the dynamic linker was
1022 loaded so that we can load its symbols and place a breakpoint
1023 in the dynamic linker itself.
1025 This address is stored on the stack. However, I've been unable
1026 to find any magic formula to find it for Solaris (appears to
1027 be trivial on GNU/Linux). Therefore, we have to try an alternate
1028 mechanism to find the dynamic linker's base address. */
1030 tmp_fd
= solib_open (buf
, &tmp_pathname
);
1032 tmp_bfd
= bfd_fdopenr (tmp_pathname
, gnutarget
, tmp_fd
);
1034 if (tmp_bfd
== NULL
)
1035 goto bkpt_at_symbol
;
1037 /* Make sure the dynamic linker's really a useful object. */
1038 if (!bfd_check_format (tmp_bfd
, bfd_object
))
1040 warning ("Unable to grok dynamic linker %s as an object file", buf
);
1041 bfd_close (tmp_bfd
);
1042 goto bkpt_at_symbol
;
1045 /* Now convert the TMP_BFD into a target. That way target, as
1046 well as BFD operations can be used. Note that closing the
1047 target will also close the underlying bfd. */
1048 tmp_bfd_target
= target_bfd_reopen (tmp_bfd
);
1050 /* If the entry in _DYNAMIC for the dynamic linker has already
1051 been filled in, we can read its base address from there. */
1052 inferior_sos
= svr4_current_sos ();
1055 /* Connected to a running target. Update our shared library table. */
1056 solib_add (NULL
, 0, NULL
, auto_solib_add
);
1058 while (inferior_sos
)
1060 if (strcmp (buf
, inferior_sos
->so_original_name
) == 0)
1062 load_addr_found
= 1;
1063 load_addr
= LM_ADDR (inferior_sos
);
1066 inferior_sos
= inferior_sos
->next
;
1069 /* Otherwise we find the dynamic linker's base address by examining
1070 the current pc (which should point at the entry point for the
1071 dynamic linker) and subtracting the offset of the entry point. */
1072 if (!load_addr_found
)
1073 load_addr
= (read_pc ()
1074 - exec_entry_point (tmp_bfd
, tmp_bfd_target
));
1076 /* Record the relocated start and end address of the dynamic linker
1077 text and plt section for svr4_in_dynsym_resolve_code. */
1078 interp_sect
= bfd_get_section_by_name (tmp_bfd
, ".text");
1081 interp_text_sect_low
=
1082 bfd_section_vma (tmp_bfd
, interp_sect
) + load_addr
;
1083 interp_text_sect_high
=
1084 interp_text_sect_low
+ bfd_section_size (tmp_bfd
, interp_sect
);
1086 interp_sect
= bfd_get_section_by_name (tmp_bfd
, ".plt");
1089 interp_plt_sect_low
=
1090 bfd_section_vma (tmp_bfd
, interp_sect
) + load_addr
;
1091 interp_plt_sect_high
=
1092 interp_plt_sect_low
+ bfd_section_size (tmp_bfd
, interp_sect
);
1095 /* Now try to set a breakpoint in the dynamic linker. */
1096 for (bkpt_namep
= solib_break_names
; *bkpt_namep
!= NULL
; bkpt_namep
++)
1098 /* On ABI's that use function descriptors, there are usually
1099 two linker symbols associated with each C function: one
1100 pointing at the actual entry point of the machine code,
1101 and one pointing at the function's descriptor. The
1102 latter symbol has the same name as the C function.
1104 What we're looking for here is the machine code entry
1105 point, so we are only interested in symbols in code
1107 sym_addr
= bfd_lookup_symbol (tmp_bfd
, *bkpt_namep
, SEC_CODE
);
1112 /* We're done with both the temporary bfd and target. Remember,
1113 closing the target closes the underlying bfd. */
1114 target_close (tmp_bfd_target
, 0);
1118 create_solib_event_breakpoint (load_addr
+ sym_addr
);
1122 /* For whatever reason we couldn't set a breakpoint in the dynamic
1123 linker. Warn and drop into the old code. */
1125 warning ("Unable to find dynamic linker breakpoint function.\nGDB will be unable to debug shared library initializers\nand track explicitly loaded dynamic code.");
1128 /* Scan through the list of symbols, trying to look up the symbol and
1129 set a breakpoint there. Terminate loop when we/if we succeed. */
1131 breakpoint_addr
= 0;
1132 for (bkpt_namep
= bkpt_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 /* Nothing good happened. */
1145 #endif /* BKPT_AT_SYMBOL */
1154 special_symbol_handling -- additional shared library symbol handling
1158 void special_symbol_handling ()
1162 Once the symbols from a shared object have been loaded in the usual
1163 way, we are called to do any system specific symbol handling that
1166 For SunOS4, this consisted of grunging around in the dynamic
1167 linkers structures to find symbol definitions for "common" symbols
1168 and adding them to the minimal symbol table for the runtime common
1171 However, for SVR4, there's nothing to do.
1176 svr4_special_symbol_handling (void)
1180 /* Relocate the main executable. This function should be called upon
1181 stopping the inferior process at the entry point to the program.
1182 The entry point from BFD is compared to the PC and if they are
1183 different, the main executable is relocated by the proper amount.
1185 As written it will only attempt to relocate executables which
1186 lack interpreter sections. It seems likely that only dynamic
1187 linker executables will get relocated, though it should work
1188 properly for a position-independent static executable as well. */
1191 svr4_relocate_main_executable (void)
1193 asection
*interp_sect
;
1194 CORE_ADDR pc
= read_pc ();
1196 /* Decide if the objfile needs to be relocated. As indicated above,
1197 we will only be here when execution is stopped at the beginning
1198 of the program. Relocation is necessary if the address at which
1199 we are presently stopped differs from the start address stored in
1200 the executable AND there's no interpreter section. The condition
1201 regarding the interpreter section is very important because if
1202 there *is* an interpreter section, execution will begin there
1203 instead. When there is an interpreter section, the start address
1204 is (presumably) used by the interpreter at some point to start
1205 execution of the program.
1207 If there is an interpreter, it is normal for it to be set to an
1208 arbitrary address at the outset. The job of finding it is
1209 handled in enable_break().
1211 So, to summarize, relocations are necessary when there is no
1212 interpreter section and the start address obtained from the
1213 executable is different from the address at which GDB is
1216 [ The astute reader will note that we also test to make sure that
1217 the executable in question has the DYNAMIC flag set. It is my
1218 opinion that this test is unnecessary (undesirable even). It
1219 was added to avoid inadvertent relocation of an executable
1220 whose e_type member in the ELF header is not ET_DYN. There may
1221 be a time in the future when it is desirable to do relocations
1222 on other types of files as well in which case this condition
1223 should either be removed or modified to accomodate the new file
1224 type. (E.g, an ET_EXEC executable which has been built to be
1225 position-independent could safely be relocated by the OS if
1226 desired. It is true that this violates the ABI, but the ABI
1227 has been known to be bent from time to time.) - Kevin, Nov 2000. ]
1230 interp_sect
= bfd_get_section_by_name (exec_bfd
, ".interp");
1231 if (interp_sect
== NULL
1232 && (bfd_get_file_flags (exec_bfd
) & DYNAMIC
) != 0
1233 && (exec_entry_point (exec_bfd
, &exec_ops
) != pc
))
1235 struct cleanup
*old_chain
;
1236 struct section_offsets
*new_offsets
;
1238 CORE_ADDR displacement
;
1240 /* It is necessary to relocate the objfile. The amount to
1241 relocate by is simply the address at which we are stopped
1242 minus the starting address from the executable.
1244 We relocate all of the sections by the same amount. This
1245 behavior is mandated by recent editions of the System V ABI.
1246 According to the System V Application Binary Interface,
1247 Edition 4.1, page 5-5:
1249 ... Though the system chooses virtual addresses for
1250 individual processes, it maintains the segments' relative
1251 positions. Because position-independent code uses relative
1252 addressesing between segments, the difference between
1253 virtual addresses in memory must match the difference
1254 between virtual addresses in the file. The difference
1255 between the virtual address of any segment in memory and
1256 the corresponding virtual address in the file is thus a
1257 single constant value for any one executable or shared
1258 object in a given process. This difference is the base
1259 address. One use of the base address is to relocate the
1260 memory image of the program during dynamic linking.
1262 The same language also appears in Edition 4.0 of the System V
1263 ABI and is left unspecified in some of the earlier editions. */
1265 displacement
= pc
- exec_entry_point (exec_bfd
, &exec_ops
);
1268 new_offsets
= xcalloc (symfile_objfile
->num_sections
,
1269 sizeof (struct section_offsets
));
1270 old_chain
= make_cleanup (xfree
, new_offsets
);
1272 for (i
= 0; i
< symfile_objfile
->num_sections
; i
++)
1274 if (displacement
!= ANOFFSET (symfile_objfile
->section_offsets
, i
))
1276 new_offsets
->offsets
[i
] = displacement
;
1280 objfile_relocate (symfile_objfile
, new_offsets
);
1282 do_cleanups (old_chain
);
1290 svr4_solib_create_inferior_hook -- shared library startup support
1294 void svr4_solib_create_inferior_hook()
1298 When gdb starts up the inferior, it nurses it along (through the
1299 shell) until it is ready to execute it's first instruction. At this
1300 point, this function gets called via expansion of the macro
1301 SOLIB_CREATE_INFERIOR_HOOK.
1303 For SunOS executables, this first instruction is typically the
1304 one at "_start", or a similar text label, regardless of whether
1305 the executable is statically or dynamically linked. The runtime
1306 startup code takes care of dynamically linking in any shared
1307 libraries, once gdb allows the inferior to continue.
1309 For SVR4 executables, this first instruction is either the first
1310 instruction in the dynamic linker (for dynamically linked
1311 executables) or the instruction at "start" for statically linked
1312 executables. For dynamically linked executables, the system
1313 first exec's /lib/libc.so.N, which contains the dynamic linker,
1314 and starts it running. The dynamic linker maps in any needed
1315 shared libraries, maps in the actual user executable, and then
1316 jumps to "start" in the user executable.
1318 For both SunOS shared libraries, and SVR4 shared libraries, we
1319 can arrange to cooperate with the dynamic linker to discover the
1320 names of shared libraries that are dynamically linked, and the
1321 base addresses to which they are linked.
1323 This function is responsible for discovering those names and
1324 addresses, and saving sufficient information about them to allow
1325 their symbols to be read at a later time.
1329 Between enable_break() and disable_break(), this code does not
1330 properly handle hitting breakpoints which the user might have
1331 set in the startup code or in the dynamic linker itself. Proper
1332 handling will probably have to wait until the implementation is
1333 changed to use the "breakpoint handler function" method.
1335 Also, what if child has exit()ed? Must exit loop somehow.
1339 svr4_solib_create_inferior_hook (void)
1341 /* Relocate the main executable if necessary. */
1342 svr4_relocate_main_executable ();
1344 if (!svr4_have_link_map_offsets ())
1346 warning ("no shared library support for this OS / ABI");
1351 if (!enable_break ())
1353 warning ("shared library handler failed to enable breakpoint");
1357 #if defined(_SCO_DS)
1358 /* SCO needs the loop below, other systems should be using the
1359 special shared library breakpoints and the shared library breakpoint
1362 Now run the target. It will eventually hit the breakpoint, at
1363 which point all of the libraries will have been mapped in and we
1364 can go groveling around in the dynamic linker structures to find
1365 out what we need to know about them. */
1367 clear_proceed_status ();
1368 stop_soon
= STOP_QUIETLY
;
1369 stop_signal
= TARGET_SIGNAL_0
;
1372 target_resume (pid_to_ptid (-1), 0, stop_signal
);
1373 wait_for_inferior ();
1375 while (stop_signal
!= TARGET_SIGNAL_TRAP
);
1376 stop_soon
= NO_STOP_QUIETLY
;
1377 #endif /* defined(_SCO_DS) */
1381 svr4_clear_solib (void)
1387 svr4_free_so (struct so_list
*so
)
1389 xfree (so
->lm_info
->lm
);
1390 xfree (so
->lm_info
);
1394 /* Clear any bits of ADDR that wouldn't fit in a target-format
1395 data pointer. "Data pointer" here refers to whatever sort of
1396 address the dynamic linker uses to manage its sections. At the
1397 moment, we don't support shared libraries on any processors where
1398 code and data pointers are different sizes.
1400 This isn't really the right solution. What we really need here is
1401 a way to do arithmetic on CORE_ADDR values that respects the
1402 natural pointer/address correspondence. (For example, on the MIPS,
1403 converting a 32-bit pointer to a 64-bit CORE_ADDR requires you to
1404 sign-extend the value. There, simply truncating the bits above
1405 TARGET_PTR_BIT, as we do below, is no good.) This should probably
1406 be a new gdbarch method or something. */
1408 svr4_truncate_ptr (CORE_ADDR addr
)
1410 if (TARGET_PTR_BIT
== sizeof (CORE_ADDR
) * 8)
1411 /* We don't need to truncate anything, and the bit twiddling below
1412 will fail due to overflow problems. */
1415 return addr
& (((CORE_ADDR
) 1 << TARGET_PTR_BIT
) - 1);
1420 svr4_relocate_section_addresses (struct so_list
*so
,
1421 struct section_table
*sec
)
1423 sec
->addr
= svr4_truncate_ptr (sec
->addr
+ LM_ADDR (so
));
1424 sec
->endaddr
= svr4_truncate_ptr (sec
->endaddr
+ LM_ADDR (so
));
1428 /* Fetch a link_map_offsets structure for native targets using struct
1429 definitions from link.h. See solib-legacy.c for the function
1430 which does the actual work.
1432 Note: For non-native targets (i.e. cross-debugging situations),
1433 a target specific fetch_link_map_offsets() function should be
1434 defined and registered via set_solib_svr4_fetch_link_map_offsets(). */
1436 static struct link_map_offsets
*
1437 legacy_fetch_link_map_offsets (void)
1439 if (legacy_svr4_fetch_link_map_offsets_hook
)
1440 return legacy_svr4_fetch_link_map_offsets_hook ();
1443 internal_error (__FILE__
, __LINE__
,
1444 "legacy_fetch_link_map_offsets called without legacy "
1445 "link_map support enabled.");
1450 /* Fetch a link_map_offsets structure using the method registered in the
1451 architecture vector. */
1453 static struct link_map_offsets
*
1454 svr4_fetch_link_map_offsets (void)
1456 struct link_map_offsets
*(*flmo
)(void) =
1457 gdbarch_data (current_gdbarch
, fetch_link_map_offsets_gdbarch_data
);
1461 internal_error (__FILE__
, __LINE__
,
1462 "svr4_fetch_link_map_offsets: fetch_link_map_offsets "
1463 "method not defined for this architecture.");
1470 /* Return 1 if a link map offset fetcher has been defined, 0 otherwise. */
1472 svr4_have_link_map_offsets (void)
1474 struct link_map_offsets
*(*flmo
)(void) =
1475 gdbarch_data (current_gdbarch
, fetch_link_map_offsets_gdbarch_data
);
1477 || (flmo
== legacy_fetch_link_map_offsets
1478 && legacy_svr4_fetch_link_map_offsets_hook
== NULL
))
1484 /* set_solib_svr4_fetch_link_map_offsets() is intended to be called by
1485 a <arch>_gdbarch_init() function. It is used to establish an
1486 architecture specific link_map_offsets fetcher for the architecture
1490 set_solib_svr4_fetch_link_map_offsets (struct gdbarch
*gdbarch
,
1491 struct link_map_offsets
*(*flmo
) (void))
1493 set_gdbarch_data (gdbarch
, fetch_link_map_offsets_gdbarch_data
, flmo
);
1496 /* Initialize the architecture-specific link_map_offsets fetcher.
1497 This is called after <arch>_gdbarch_init() has set up its `struct
1498 gdbarch' for the new architecture, and is only called if the
1499 link_map_offsets fetcher isn't already initialized (which is
1500 usually done by calling set_solib_svr4_fetch_link_map_offsets()
1501 above in <arch>_gdbarch_init()). Therefore we attempt to provide a
1502 reasonable alternative (for native targets anyway) if the
1503 <arch>_gdbarch_init() fails to call
1504 set_solib_svr4_fetch_link_map_offsets(). */
1507 init_fetch_link_map_offsets (struct gdbarch
*gdbarch
)
1509 return legacy_fetch_link_map_offsets
;
1512 /* Most OS'es that have SVR4-style ELF dynamic libraries define a
1513 `struct r_debug' and a `struct link_map' that are binary compatible
1514 with the origional SVR4 implementation. */
1516 /* Fetch (and possibly build) an appropriate `struct link_map_offsets'
1517 for an ILP32 SVR4 system. */
1519 struct link_map_offsets
*
1520 svr4_ilp32_fetch_link_map_offsets (void)
1522 static struct link_map_offsets lmo
;
1523 static struct link_map_offsets
*lmp
= NULL
;
1529 /* Everything we need is in the first 8 bytes. */
1530 lmo
.r_debug_size
= 8;
1531 lmo
.r_map_offset
= 4;
1534 /* Everything we need is in the first 20 bytes. */
1535 lmo
.link_map_size
= 20;
1536 lmo
.l_addr_offset
= 0;
1537 lmo
.l_addr_size
= 4;
1538 lmo
.l_name_offset
= 4;
1539 lmo
.l_name_size
= 4;
1540 lmo
.l_next_offset
= 12;
1541 lmo
.l_next_size
= 4;
1542 lmo
.l_prev_offset
= 16;
1543 lmo
.l_prev_size
= 4;
1549 /* Fetch (and possibly build) an appropriate `struct link_map_offsets'
1550 for an LP64 SVR4 system. */
1552 struct link_map_offsets
*
1553 svr4_lp64_fetch_link_map_offsets (void)
1555 static struct link_map_offsets lmo
;
1556 static struct link_map_offsets
*lmp
= NULL
;
1562 /* Everything we need is in the first 16 bytes. */
1563 lmo
.r_debug_size
= 16;
1564 lmo
.r_map_offset
= 8;
1567 /* Everything we need is in the first 40 bytes. */
1568 lmo
.link_map_size
= 40;
1569 lmo
.l_addr_offset
= 0;
1570 lmo
.l_addr_size
= 8;
1571 lmo
.l_name_offset
= 8;
1572 lmo
.l_name_size
= 8;
1573 lmo
.l_next_offset
= 24;
1574 lmo
.l_next_size
= 8;
1575 lmo
.l_prev_offset
= 32;
1576 lmo
.l_prev_size
= 8;
1583 static struct target_so_ops svr4_so_ops
;
1585 extern initialize_file_ftype _initialize_svr4_solib
; /* -Wmissing-prototypes */
1588 _initialize_svr4_solib (void)
1590 fetch_link_map_offsets_gdbarch_data
=
1591 register_gdbarch_data (init_fetch_link_map_offsets
);
1593 svr4_so_ops
.relocate_section_addresses
= svr4_relocate_section_addresses
;
1594 svr4_so_ops
.free_so
= svr4_free_so
;
1595 svr4_so_ops
.clear_solib
= svr4_clear_solib
;
1596 svr4_so_ops
.solib_create_inferior_hook
= svr4_solib_create_inferior_hook
;
1597 svr4_so_ops
.special_symbol_handling
= svr4_special_symbol_handling
;
1598 svr4_so_ops
.current_sos
= svr4_current_sos
;
1599 svr4_so_ops
.open_symbol_file_object
= open_symbol_file_object
;
1600 svr4_so_ops
.in_dynsym_resolve_code
= svr4_in_dynsym_resolve_code
;
1602 /* FIXME: Don't do this here. *_gdbarch_init() should set so_ops. */
1603 current_target_so_ops
= &svr4_so_ops
;