1 /* Handle PA64 shared libraries for GDB, the GNU Debugger.
3 Copyright (C) 2004, 2007, 2008, 2009 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>.
20 HP in their infinite stupidity choose not to use standard ELF dynamic
21 linker interfaces. They also choose not to make their ELF dymamic
22 linker interfaces compatible with the SOM dynamic linker. The
23 net result is we can not use either of the existing somsolib.c or
24 solib.c. What a crock.
26 Even more disgusting. This file depends on functions provided only
27 in certain PA64 libraries. Thus this file is supposed to only be
28 used native. When will HP ever learn that they need to provide the
29 same functionality in all their libraries! */
41 #include "hppa-tdep.h"
44 #include "solib-pa64.h"
48 /* We can build this file only when running natively on 64-bit HP/UX.
49 We check for that by checking for the elf_hp.h header file. */
50 #if defined(HAVE_ELF_HP_H) && defined(__LP64__)
52 /* FIXME: kettenis/20041213: These includes should be eliminated. */
58 struct load_module_desc desc
;
62 /* When adding fields, be sure to clear them in _initialize_pa64_solib. */
65 CORE_ADDR dld_flags_addr
;
67 struct bfd_section
*dyninfo_sect
;
68 int have_read_dld_descriptor
;
71 CORE_ADDR load_map_addr
;
72 struct load_module_desc dld_desc
;
76 static dld_cache_t dld_cache
;
79 read_dynamic_info (asection
*dyninfo_sect
, dld_cache_t
*dld_cache_p
);
82 pa64_relocate_section_addresses (struct so_list
*so
,
83 struct target_section
*sec
)
85 asection
*asec
= sec
->the_bfd_section
;
86 CORE_ADDR load_offset
;
88 /* Relocate all the sections based on where they got loaded. */
90 load_offset
= bfd_section_vma (so
->abfd
, asec
) - asec
->filepos
;
92 if (asec
->flags
& SEC_CODE
)
94 sec
->addr
+= so
->lm_info
->desc
.text_base
- load_offset
;
95 sec
->endaddr
+= so
->lm_info
->desc
.text_base
- load_offset
;
97 else if (asec
->flags
& SEC_DATA
)
99 sec
->addr
+= so
->lm_info
->desc
.data_base
- load_offset
;
100 sec
->endaddr
+= so
->lm_info
->desc
.data_base
- load_offset
;
105 pa64_free_so (struct so_list
*so
)
111 pa64_clear_solib (void)
115 /* Wrapper for target_read_memory for dlgetmodinfo. */
118 pa64_target_read_memory (void *buffer
, CORE_ADDR ptr
, size_t bufsiz
, int ident
)
120 if (target_read_memory (ptr
, buffer
, bufsiz
) != 0)
125 /* Read the dynamic linker's internal shared library descriptor.
127 This must happen after dld starts running, so we can't do it in
128 read_dynamic_info. Record the fact that we have loaded the
129 descriptor. If the library is archive bound or the load map
130 hasn't been setup, then return zero; else return nonzero. */
133 read_dld_descriptor (void)
136 asection
*dyninfo_sect
;
138 /* If necessary call read_dynamic_info to extract the contents of the
139 .dynamic section from the shared library. */
140 if (!dld_cache
.is_valid
)
142 if (symfile_objfile
== NULL
)
143 error (_("No object file symbols."));
145 dyninfo_sect
= bfd_get_section_by_name (symfile_objfile
->obfd
,
152 if (!read_dynamic_info (dyninfo_sect
, &dld_cache
))
153 error (_("Unable to read in .dynamic section information."));
156 /* Read the load map pointer. */
157 if (target_read_memory (dld_cache
.load_map_addr
,
158 (char *) &dld_cache
.load_map
,
159 sizeof (dld_cache
.load_map
))
162 error (_("Error while reading in load map pointer."));
165 if (!dld_cache
.load_map
)
168 /* Read in the dld load module descriptor */
169 if (dlgetmodinfo (-1,
171 sizeof (dld_cache
.dld_desc
),
172 pa64_target_read_memory
,
177 error (_("Error trying to get information about dynamic linker."));
180 /* Indicate that we have loaded the dld descriptor. */
181 dld_cache
.have_read_dld_descriptor
= 1;
187 /* Read the .dynamic section and extract the information of interest,
188 which is stored in dld_cache. The routine elf_locate_base in solib.c
189 was used as a model for this. */
192 read_dynamic_info (asection
*dyninfo_sect
, dld_cache_t
*dld_cache_p
)
196 CORE_ADDR dyninfo_addr
;
197 int dyninfo_sect_size
;
198 CORE_ADDR entry_addr
;
200 /* Read in .dynamic section, silently ignore errors. */
201 dyninfo_addr
= bfd_section_vma (symfile_objfile
->obfd
, dyninfo_sect
);
202 dyninfo_sect_size
= bfd_section_size (exec_bfd
, dyninfo_sect
);
203 buf
= alloca (dyninfo_sect_size
);
204 if (target_read_memory (dyninfo_addr
, buf
, dyninfo_sect_size
))
207 /* Scan the .dynamic section and record the items of interest.
208 In particular, DT_HP_DLD_FLAGS */
209 for (bufend
= buf
+ dyninfo_sect_size
, entry_addr
= dyninfo_addr
;
211 buf
+= sizeof (Elf64_Dyn
), entry_addr
+= sizeof (Elf64_Dyn
))
213 Elf64_Dyn
*x_dynp
= (Elf64_Dyn
*)buf
;
214 Elf64_Sxword dyn_tag
;
218 pbuf
= alloca (gdbarch_ptr_bit (current_gdbarch
) / HOST_CHAR_BIT
);
219 dyn_tag
= bfd_h_get_64 (symfile_objfile
->obfd
,
220 (bfd_byte
*) &x_dynp
->d_tag
);
222 /* We can't use a switch here because dyn_tag is 64 bits and HP's
223 lame comiler does not handle 64bit items in switch statements. */
224 if (dyn_tag
== DT_NULL
)
226 else if (dyn_tag
== DT_HP_DLD_FLAGS
)
228 /* Set dld_flags_addr and dld_flags in *dld_cache_p */
229 dld_cache_p
->dld_flags_addr
= entry_addr
+ offsetof(Elf64_Dyn
, d_un
);
230 if (target_read_memory (dld_cache_p
->dld_flags_addr
,
231 (char*) &dld_cache_p
->dld_flags
,
232 sizeof (dld_cache_p
->dld_flags
))
235 error (_("Error while reading in .dynamic section of the program."));
238 else if (dyn_tag
== DT_HP_LOAD_MAP
)
240 /* Dld will place the address of the load map at load_map_addr
241 after it starts running. */
242 if (target_read_memory (entry_addr
+ offsetof(Elf64_Dyn
,
244 (char*) &dld_cache_p
->load_map_addr
,
245 sizeof (dld_cache_p
->load_map_addr
))
248 error (_("Error while reading in .dynamic section of the program."));
253 /* tag is not of interest */
257 /* Record other information and set is_valid to 1. */
258 dld_cache_p
->dyninfo_sect
= dyninfo_sect
;
260 /* Verify that we read in required info. These fields are re-set to zero
261 in pa64_solib_restart. */
263 if (dld_cache_p
->dld_flags_addr
!= 0 && dld_cache_p
->load_map_addr
!= 0)
264 dld_cache_p
->is_valid
= 1;
272 bfd_lookup_symbol -- lookup the value for a specific symbol
274 An expensive way to lookup the value of a single symbol for
275 bfd's that are only temporary anyway. This is used by the
276 shared library support to find the address of the debugger
277 interface structures in the shared library.
279 Note that 0 is specifically allowed as an error return (no
284 bfd_lookup_symbol (bfd
*abfd
, char *symname
)
286 unsigned int storage_needed
;
288 asymbol
**symbol_table
;
289 unsigned int number_of_symbols
;
291 struct cleanup
*back_to
;
292 CORE_ADDR symaddr
= 0;
294 storage_needed
= bfd_get_symtab_upper_bound (abfd
);
296 if (storage_needed
> 0)
298 symbol_table
= (asymbol
**) xmalloc (storage_needed
);
299 back_to
= make_cleanup (xfree
, symbol_table
);
300 number_of_symbols
= bfd_canonicalize_symtab (abfd
, symbol_table
);
302 for (i
= 0; i
< number_of_symbols
; i
++)
304 sym
= *symbol_table
++;
305 if (strcmp (sym
->name
, symname
) == 0)
307 /* Bfd symbols are section relative. */
308 symaddr
= sym
->value
+ sym
->section
->vma
;
312 do_cleanups (back_to
);
318 /* This hook gets called just before the first instruction in the
319 inferior process is executed.
321 This is our opportunity to set magic flags in the inferior so
322 that GDB can be notified when a shared library is mapped in and
323 to tell the dynamic linker that a private copy of the library is
324 needed (so GDB can set breakpoints in the library).
326 We need to set DT_HP_DEBUG_CALLBACK to indicate that we want the
327 dynamic linker to call the breakpoint routine for significant events.
328 We used to set DT_HP_DEBUG_PRIVATE to indicate that shared libraries
329 should be mapped private. However, this flag can be set using
330 "chatr +dbg enable". Not setting DT_HP_DEBUG_PRIVATE allows debugging
331 with shared libraries mapped shareable. */
334 pa64_solib_create_inferior_hook (void)
336 struct minimal_symbol
*msymbol
;
337 unsigned int dld_flags
, status
;
338 asection
*shlib_info
, *interp_sect
;
340 struct objfile
*objfile
;
343 /* First, remove all the solib event breakpoints. Their addresses
344 may have changed since the last time we ran the program. */
345 remove_solib_event_breakpoints ();
347 if (symfile_objfile
== NULL
)
350 /* First see if the objfile was dynamically linked. */
351 shlib_info
= bfd_get_section_by_name (symfile_objfile
->obfd
, ".dynamic");
355 /* It's got a .dynamic section, make sure it's not empty. */
356 if (bfd_section_size (symfile_objfile
->obfd
, shlib_info
) == 0)
359 /* Read in the .dynamic section. */
360 if (! read_dynamic_info (shlib_info
, &dld_cache
))
361 error (_("Unable to read the .dynamic section."));
363 /* If the libraries were not mapped private, warn the user. */
364 if ((dld_cache
.dld_flags
& DT_HP_DEBUG_PRIVATE
) == 0)
366 (_("Private mapping of shared library text was not specified\n"
367 "by the executable; setting a breakpoint in a shared library which\n"
368 "is not privately mapped will not work. See the HP-UX 11i v3 chatr\n"
369 "manpage for methods to privately map shared library text."));
371 /* Turn on the flags we care about. */
372 dld_cache
.dld_flags
|= DT_HP_DEBUG_CALLBACK
;
373 status
= target_write_memory (dld_cache
.dld_flags_addr
,
374 (char *) &dld_cache
.dld_flags
,
375 sizeof (dld_cache
.dld_flags
));
377 error (_("Unable to modify dynamic linker flags."));
379 /* Now we have to create a shared library breakpoint in the dynamic
380 linker. This can be somewhat tricky since the symbol is inside
381 the dynamic linker (for which we do not have symbols or a base
382 load address! Luckily I wrote this code for solib.c years ago. */
383 interp_sect
= bfd_get_section_by_name (exec_bfd
, ".interp");
386 unsigned int interp_sect_size
;
390 CORE_ADDR sym_addr
= 0;
392 /* Read the contents of the .interp section into a local buffer;
393 the contents specify the dynamic linker this program uses. */
394 interp_sect_size
= bfd_section_size (exec_bfd
, interp_sect
);
395 buf
= alloca (interp_sect_size
);
396 bfd_get_section_contents (exec_bfd
, interp_sect
,
397 buf
, 0, interp_sect_size
);
399 /* Now we need to figure out where the dynamic linker was
400 loaded so that we can load its symbols and place a breakpoint
401 in the dynamic linker itself.
403 This address is stored on the stack. However, I've been unable
404 to find any magic formula to find it for Solaris (appears to
405 be trivial on GNU/Linux). Therefore, we have to try an alternate
406 mechanism to find the dynamic linker's base address. */
407 tmp_bfd
= bfd_openr (buf
, gnutarget
);
411 /* Make sure the dynamic linker's really a useful object. */
412 if (!bfd_check_format (tmp_bfd
, bfd_object
))
414 warning (_("Unable to grok dynamic linker %s as an object file"), buf
);
419 /* We find the dynamic linker's base address by examining the
420 current pc (which point at the entry point for the dynamic
421 linker) and subtracting the offset of the entry point.
423 Also note the breakpoint is the second instruction in the
425 load_addr
= regcache_read_pc (get_current_regcache ())
426 - tmp_bfd
->start_address
;
427 sym_addr
= bfd_lookup_symbol (tmp_bfd
, "__dld_break");
428 sym_addr
= load_addr
+ sym_addr
+ 4;
430 /* Create the shared library breakpoint. */
433 = create_solib_event_breakpoint (sym_addr
);
435 /* The breakpoint is actually hard-coded into the dynamic linker,
436 so we don't need to actually insert a breakpoint instruction
437 there. In fact, the dynamic linker's code is immutable, even to
438 ttrace, so we shouldn't even try to do that. For cases like
439 this, we have "permanent" breakpoints. */
440 make_breakpoint_permanent (b
);
443 /* We're done with the temporary bfd. */
449 pa64_special_symbol_handling (void)
453 static struct so_list
*
454 pa64_current_sos (void)
456 struct so_list
*head
= 0;
457 struct so_list
**link_ptr
= &head
;
460 /* Read in the load map pointer if we have not done so already. */
461 if (! dld_cache
.have_read_dld_descriptor
)
462 if (! read_dld_descriptor ())
465 for (dll_index
= -1; ; dll_index
++)
467 struct load_module_desc dll_desc
;
470 struct cleanup
*old_chain
;
475 /* Read in the load module descriptor. */
476 if (dlgetmodinfo (dll_index
, &dll_desc
, sizeof (dll_desc
),
477 pa64_target_read_memory
, 0, dld_cache
.load_map
)
481 /* Get the name of the shared library. */
482 dll_path
= (char *)dlgetname (&dll_desc
, sizeof (dll_desc
),
483 pa64_target_read_memory
,
484 0, dld_cache
.load_map
);
486 new = (struct so_list
*) xmalloc (sizeof (struct so_list
));
487 memset (new, 0, sizeof (struct so_list
));
488 new->lm_info
= (struct lm_info
*) xmalloc (sizeof (struct lm_info
));
489 memset (new->lm_info
, 0, sizeof (struct lm_info
));
491 strncpy (new->so_name
, dll_path
, SO_NAME_MAX_PATH_SIZE
- 1);
492 new->so_name
[SO_NAME_MAX_PATH_SIZE
- 1] = '\0';
493 strcpy (new->so_original_name
, new->so_name
);
495 memcpy (&new->lm_info
->desc
, &dll_desc
, sizeof (dll_desc
));
497 #ifdef SOLIB_PA64_DBG
499 struct load_module_desc
*d
= &new->lm_info
->desc
;
500 printf ("\n+ library \"%s\" is described at index %d\n", new->so_name
,
502 printf (" text_base = 0x%llx\n", d
->text_base
);
503 printf (" text_size = 0x%llx\n", d
->text_size
);
504 printf (" data_base = 0x%llx\n", d
->data_base
);
505 printf (" data_size = 0x%llx\n", d
->data_size
);
506 printf (" unwind_base = 0x%llx\n", d
->unwind_base
);
507 printf (" linkage_ptr = 0x%llx\n", d
->linkage_ptr
);
508 printf (" phdr_base = 0x%llx\n", d
->phdr_base
);
509 printf (" tls_size = 0x%llx\n", d
->tls_size
);
510 printf (" tls_start_addr = 0x%llx\n", d
->tls_start_addr
);
511 printf (" unwind_size = 0x%llx\n", d
->unwind_size
);
512 printf (" tls_index = 0x%llx\n", d
->tls_index
);
516 /* Link the new object onto the list. */
519 link_ptr
= &new->next
;
526 pa64_open_symbol_file_object (void *from_ttyp
)
528 int from_tty
= *(int *)from_ttyp
;
530 struct load_module_desc dll_desc
;
534 if (!query (_("Attempt to reload symbols from process? ")))
537 /* Read in the load map pointer if we have not done so already. */
538 if (! dld_cache
.have_read_dld_descriptor
)
539 if (! read_dld_descriptor ())
542 /* Read in the load module descriptor. */
543 if (dlgetmodinfo (0, &dll_desc
, sizeof (dll_desc
),
544 pa64_target_read_memory
, 0, dld_cache
.load_map
) == 0)
547 /* Get the name of the shared library. */
548 dll_path
= (char *)dlgetname (&dll_desc
, sizeof (dll_desc
),
549 pa64_target_read_memory
,
550 0, dld_cache
.load_map
);
552 /* Have a pathname: read the symbol file. */
553 symbol_file_add_main (dll_path
, from_tty
);
558 /* Return nonzero if PC is an address inside the dynamic linker. */
560 pa64_in_dynsym_resolve_code (CORE_ADDR pc
)
562 asection
*shlib_info
;
564 if (symfile_objfile
== NULL
)
567 if (!dld_cache
.have_read_dld_descriptor
)
568 if (!read_dld_descriptor ())
571 return (pc
>= dld_cache
.dld_desc
.text_base
572 && pc
< dld_cache
.dld_desc
.text_base
+ dld_cache
.dld_desc
.text_size
);
576 /* Return the GOT value for the shared library in which ADDR belongs. If
577 ADDR isn't in any known shared library, return zero. */
580 pa64_solib_get_got_by_pc (CORE_ADDR addr
)
582 struct so_list
*so_list
= master_so_list ();
583 CORE_ADDR got_value
= 0;
587 if (so_list
->lm_info
->desc
.text_base
<= addr
588 && ((so_list
->lm_info
->desc
.text_base
589 + so_list
->lm_info
->desc
.text_size
)
592 got_value
= so_list
->lm_info
->desc
.linkage_ptr
;
595 so_list
= so_list
->next
;
600 /* Get some HPUX-specific data from a shared lib. */
602 pa64_solib_thread_start_addr (struct so_list
*so
)
604 return so
->lm_info
->desc
.tls_start_addr
;
608 /* Return the address of the handle of the shared library in which ADDR
609 belongs. If ADDR isn't in any known shared library, return zero. */
612 pa64_solib_get_solib_by_pc (CORE_ADDR addr
)
614 struct so_list
*so_list
= master_so_list ();
615 CORE_ADDR retval
= 0;
619 if (so_list
->lm_info
->desc
.text_base
<= addr
620 && ((so_list
->lm_info
->desc
.text_base
621 + so_list
->lm_info
->desc
.text_size
)
624 retval
= so_list
->lm_info
->desc_addr
;
627 so_list
= so_list
->next
;
632 /* pa64 libraries do not seem to set the section offsets in a standard (i.e.
633 SVr4) way; the text section offset stored in the file doesn't correspond
634 to the place where the library is actually loaded into memory. Instead,
635 we rely on the dll descriptor to tell us where things were loaded. */
637 pa64_solib_get_text_base (struct objfile
*objfile
)
641 for (so
= master_so_list (); so
; so
= so
->next
)
642 if (so
->objfile
== objfile
)
643 return so
->lm_info
->desc
.text_base
;
648 static struct target_so_ops pa64_so_ops
;
650 extern initialize_file_ftype _initialize_pa64_solib
; /* -Wmissing-prototypes */
653 _initialize_pa64_solib (void)
655 pa64_so_ops
.relocate_section_addresses
= pa64_relocate_section_addresses
;
656 pa64_so_ops
.free_so
= pa64_free_so
;
657 pa64_so_ops
.clear_solib
= pa64_clear_solib
;
658 pa64_so_ops
.solib_create_inferior_hook
= pa64_solib_create_inferior_hook
;
659 pa64_so_ops
.special_symbol_handling
= pa64_special_symbol_handling
;
660 pa64_so_ops
.current_sos
= pa64_current_sos
;
661 pa64_so_ops
.open_symbol_file_object
= pa64_open_symbol_file_object
;
662 pa64_so_ops
.in_dynsym_resolve_code
= pa64_in_dynsym_resolve_code
;
664 memset (&dld_cache
, 0, sizeof (dld_cache
));
667 void pa64_solib_select (struct gdbarch
*gdbarch
)
669 struct gdbarch_tdep
*tdep
= gdbarch_tdep (gdbarch
);
670 set_solib_ops (gdbarch
, &pa64_so_ops
);
672 tdep
->solib_thread_start_addr
= pa64_solib_thread_start_addr
;
673 tdep
->solib_get_got_by_pc
= pa64_solib_get_got_by_pc
;
674 tdep
->solib_get_solib_by_pc
= pa64_solib_get_solib_by_pc
;
675 tdep
->solib_get_text_base
= pa64_solib_get_text_base
;
678 #else /* HAVE_ELF_HP_H */
680 extern initialize_file_ftype _initialize_pa64_solib
; /* -Wmissing-prototypes */
683 _initialize_pa64_solib (void)
687 void pa64_solib_select (struct gdbarch
*gdbarch
)
689 /* For a SOM-only target, there is no pa64 solib support. This is needed
690 for hppa-hpux-tdep.c to build. */
691 error (_("Cannot select pa64 solib support for this configuration."));