1 /* Handle OSF/1, Digital UNIX, and Tru64 shared libraries
2 for GDB, the GNU Debugger.
3 Copyright 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001
4 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., 59 Temple Place - Suite 330,
21 Boston, MA 02111-1307, USA. */
23 /* When handling shared libraries, GDB has to find out the pathnames
24 of all shared libraries that are currently loaded (to read in their
25 symbols) and where the shared libraries are loaded in memory
26 (to relocate them properly from their prelinked addresses to the
27 current load address).
29 Under OSF/1 there are two possibilities to get at this information:
31 1) Peek around in the runtime loader structures.
32 These are not documented, and they are not defined in the system
33 header files. The definitions below were obtained by experimentation,
34 but they seem stable enough.
36 2) Use the libxproc.a library, which contains the equivalent ldr_*
37 routines. The library is documented in Tru64 5.x, but as of 5.1, it
38 only allows a process to examine itself. On earlier versions, it
39 may require that the GDB executable be dynamically linked and that
40 NAT_CLIBS include -lxproc -Wl,-expect_unresolved,ldr_process_context
41 for GDB and all applications that are using libgdb.
43 We will use the peeking approach until libxproc.a works for other
48 #include <sys/types.h>
50 #include "gdb_string.h"
60 #ifdef USE_LDR_ROUTINES
64 #ifndef USE_LDR_ROUTINES
65 /* Definition of runtime loader structures, found by experimentation. */
66 #define RLD_CONTEXT_ADDRESS 0x3ffc0000000
68 /* Per-module information structure referenced by ldr_context_t.head. */
75 CORE_ADDR module_name;
76 CORE_ADDR modinfo_addr; /* used by next_link_map_member() to detect
77 the end of the shared module list */
82 CORE_ADDR regioninfo_addr;
86 /* Per-region structure referenced by ldr_module_info_t.regioninfo_addr. */
91 CORE_ADDR regionname_addr;
100 /* Structure at RLD_CONTEXT_ADDRESS specifying the start and finish addresses
101 of the shared module list. */
111 #endif /* !USE_LDR_ROUTINES */
113 /* Per-section information, stored in struct lm_info.secs. */
117 CORE_ADDR offset; /* difference between default and actual
118 virtual addresses of section .name */
119 CORE_ADDR nameaddr; /* address in inferior of section name */
120 const char *name; /* name of section, null if not fetched */
123 /* Per-module information, stored in struct so_list.lm_info. */
127 int isloader; /* whether the module is /sbin/loader */
128 int nsecs; /* length of .secs */
129 struct lm_sec secs[1]; /* variable-length array of sections, sorted
133 /* Context for iterating through the inferior's shared module list. */
137 #ifdef USE_LDR_ROUTINES
141 CORE_ADDR next; /* next element in module list */
142 CORE_ADDR tail; /* last element in module list */
146 /* Forward declaration for this module's autoinit function. */
148 extern void _initialize_osf_solib (void);
150 #ifdef USE_LDR_ROUTINES
152 /* This routine is intended to be called by ldr_* routines to read memory from
153 the current target. Usage:
155 ldr_process = ldr_core_process ();
156 ldr_set_core_reader (ldr_read_memory);
157 ldr_xdetach (ldr_process);
158 ldr_xattach (ldr_process);
160 ldr_core_process() and ldr_read_memory() are neither documented nor
161 declared in system header files. They work with OSF/1 2.x, and they might
162 work with later versions as well. */
165 ldr_read_memory (CORE_ADDR memaddr, char *myaddr, int len, int readstring)
172 target_read_string (memaddr, &buffer, len, &result);
174 strcpy (myaddr, buffer);
178 result = target_read_memory (memaddr, myaddr, len);
185 #endif /* USE_LDR_ROUTINES */
187 /* Comparison for qsort() and bsearch(): return -1, 0, or 1 according to
188 whether lm_sec *P1's name is lexically less than, equal to, or greater
192 lm_sec_cmp (const void *p1, const void *p2)
194 const struct lm_sec *lms1 = p1, *lms2 = p2;
195 return strcmp (lms1->name, lms2->name);
198 /* Sort LMI->secs so that osf_relocate_section_addresses() can binary-search
202 lm_secs_sort (struct lm_info *lmi)
204 qsort (lmi->secs, lmi->nsecs, sizeof *lmi->secs, lm_sec_cmp);
207 /* Populate name fields of LMI->secs. */
210 fetch_sec_names (struct lm_info *lmi)
212 #ifndef USE_LDR_ROUTINES
217 for (i = 0; i < lmi->nsecs; i++)
220 target_read_string (lms->nameaddr, &name, PATH_MAX, &errcode);
223 warning ("unable to read shared sec name at 0x%lx", lms->nameaddr);
232 /* target_so_ops callback. Adjust SEC's addresses after it's been mapped into
236 osf_relocate_section_addresses (struct so_list *so,
237 struct section_table *sec)
240 struct lm_sec lms_key, *lms;
242 /* Fetch SO's section names if we haven't done so already. */
244 if (lmi->nsecs && !lmi->secs[0].name)
245 fetch_sec_names (lmi);
247 /* Binary-search for offset information corresponding to SEC. */
248 lms_key.name = sec->the_bfd_section->name;
249 lms = bsearch (&lms_key, lmi->secs, lmi->nsecs, sizeof *lms, lm_sec_cmp);
252 sec->addr += lms->offset;
253 sec->endaddr += lms->offset;
257 /* target_so_ops callback. Free parts of SO allocated by this file. */
260 osf_free_so (struct so_list *so)
265 for (i = 0; i < so->lm_info->nsecs; i++)
267 name = so->lm_info->secs[i].name;
269 xfree ((void *) name);
274 /* target_so_ops callback. Discard information accumulated by this file and
275 not freed by osf_free_so(). */
278 osf_clear_solib (void)
283 /* target_so_ops callback. Prepare to handle shared libraries after the
284 inferior process has been created but before it's executed any
287 For a statically bound executable, the inferior's first instruction is the
288 one at "_start", or a similar text label. No further processing is needed
291 For a dynamically bound executable, this first instruction is somewhere
292 in the rld, and the actual user executable is not yet mapped in.
293 We continue the inferior again, rld then maps in the actual user
294 executable and any needed shared libraries and then sends
297 At that point we discover the names of all shared libraries and
298 read their symbols in.
302 This code does not properly handle hitting breakpoints which the
303 user might have set in the rld itself. Proper handling would have
304 to check if the SIGTRAP happened due to a kill call.
306 Also, what if child has exit()ed? Must exit loop somehow. */
309 osf_solib_create_inferior_hook (void)
311 /* Nothing to do for statically bound executables. */
313 if (symfile_objfile == NULL
314 || symfile_objfile->obfd == NULL
315 || ((bfd_get_file_flags (symfile_objfile->obfd) & DYNAMIC) == 0))
318 /* Now run the target. It will eventually get a SIGTRAP, at
319 which point all of the libraries will have been mapped in and we
320 can go groveling around in the rld structures to find
321 out what we need to know about them. */
323 clear_proceed_status ();
324 stop_soon = STOP_QUIETLY;
325 stop_signal = TARGET_SIGNAL_0;
328 target_resume (minus_one_ptid, 0, stop_signal);
329 wait_for_inferior ();
331 while (stop_signal != TARGET_SIGNAL_TRAP);
333 /* solib_add will call reinit_frame_cache.
334 But we are stopped in the runtime loader and we do not have symbols
335 for the runtime loader. So heuristic_proc_start will be called
336 and will put out an annoying warning.
337 Delaying the resetting of stop_soon until after symbol loading
338 suppresses the warning. */
339 solib_add ((char *) 0, 0, (struct target_ops *) 0, auto_solib_add);
340 stop_soon = NO_STOP_QUIETLY;
342 /* Enable breakpoints disabled (unnecessarily) by clear_solib(). */
343 re_enable_breakpoints_in_shlibs ();
346 /* target_so_ops callback. Do additional symbol handling, lookup, etc. after
347 symbols for a shared object have been loaded. */
350 osf_special_symbol_handling (void)
355 /* Initialize CTXT in preparation for iterating through the inferior's module
356 list using read_map(). Return success. */
359 open_map (struct read_map_ctxt *ctxt)
361 #ifdef USE_LDR_ROUTINES
362 /* Note: As originally written, ldr_my_process() was used to obtain
363 the value for ctxt->proc. This is incorrect, however, since
364 ldr_my_process() retrieves the "unique identifier" associated
365 with the current process (i.e. GDB) and not the one being
366 debugged. Presumably, the pid of the process being debugged is
367 compatible with the "unique identifier" used by the ldr_
368 routines, so we use that. */
369 ctxt->proc = ptid_get_pid (inferior_ptid);
370 if (ldr_xattach (ctxt->proc) != 0)
372 ctxt->next = LDR_NULL_MODULE;
374 CORE_ADDR ldr_context_addr, prev, next;
375 ldr_context_t ldr_context;
377 if (target_read_memory ((CORE_ADDR) RLD_CONTEXT_ADDRESS,
378 (char *) &ldr_context_addr,
379 sizeof (CORE_ADDR)) != 0)
381 if (target_read_memory (ldr_context_addr,
382 (char *) &ldr_context,
383 sizeof (ldr_context_t)) != 0)
385 ctxt->next = ldr_context.head;
386 ctxt->tail = ldr_context.tail;
391 /* Initialize SO to have module NAME, /sbin/loader indicator ISLOADR, and
392 space for NSECS sections. */
395 init_so (struct so_list *so, char *name, int isloader, int nsecs)
399 /* solib.c requires various fields to be initialized to 0. */
400 memset (so, 0, sizeof *so);
403 namelen = strlen (name);
404 if (namelen >= SO_NAME_MAX_PATH_SIZE)
405 namelen = SO_NAME_MAX_PATH_SIZE - 1;
407 memcpy (so->so_original_name, name, namelen);
408 so->so_original_name[namelen] = '\0';
409 memcpy (so->so_name, so->so_original_name, namelen + 1);
411 /* Allocate section space. */
412 so->lm_info = xmalloc ((unsigned) &(((struct lm_info *)0)->secs) +
413 nsecs * sizeof *so->lm_info);
414 so->lm_info->isloader = isloader;
415 so->lm_info->nsecs = nsecs;
416 for (i = 0; i < nsecs; i++)
417 so->lm_info->secs[i].name = NULL;
420 /* Initialize SO's section SECIDX with name address NAMEADDR, name string
421 NAME, default virtual address VADDR, and actual virtual address
425 init_sec (struct so_list *so, int secidx, CORE_ADDR nameaddr,
426 const char *name, CORE_ADDR vaddr, CORE_ADDR mapaddr)
430 lms = so->lm_info->secs + secidx;
431 lms->nameaddr = nameaddr;
433 lms->offset = mapaddr - vaddr;
436 /* If there are more elements starting at CTXT in inferior's module list,
437 store the next element in SO, advance CTXT to the next element, and return
441 read_map (struct read_map_ctxt *ctxt, struct so_list *so)
443 ldr_module_info_t minf;
444 ldr_region_info_t rinf;
446 #ifdef USE_LDR_ROUTINES
450 /* Retrieve the next element. */
451 if (ldr_next_module (ctxt->proc, &ctxt->next) != 0)
453 if (ctxt->next == LDR_NULL_MODULE)
455 if (ldr_inq_module (ctxt->proc, ctxt->next, &minf, sizeof minf, &size) != 0)
458 /* Initialize the module name and section count. */
459 init_so (so, minf.lmi_name, 0, minf.lmi_nregion);
461 /* Retrieve section names and offsets. */
462 for (i = 0; i < minf.lmi_nregion; i++)
464 if (ldr_inq_region (ctxt->proc, ctxt->next, i, &rinf,
465 sizeof rinf, &size) != 0)
467 init_sec (so, (int) i, 0, xstrdup (rinf.lri_name),
468 (CORE_ADDR) rinf.lri_vaddr, (CORE_ADDR) rinf.lri_mapaddr);
470 lm_secs_sort (so->lm_info);
475 /* Retrieve the next element. */
478 if (target_read_memory (ctxt->next, (char *) &minf, sizeof minf) != 0)
480 if (ctxt->next == ctxt->tail)
483 ctxt->next = minf.next;
485 /* Initialize the module name and section count. */
486 target_read_string (minf.module_name, &name, PATH_MAX, &errcode);
489 init_so (so, name, !minf.modinfo_addr, minf.region_count);
492 /* Retrieve section names and offsets. */
493 for (i = 0; i < minf.region_count; i++)
495 if (target_read_memory (minf.regioninfo_addr + i * sizeof rinf,
496 (char *) &rinf, sizeof rinf) != 0)
498 init_sec (so, i, rinf.regionname_addr, NULL, rinf.vaddr, rinf.mapaddr);
500 #endif /* !USE_LDR_ROUTINES */
508 /* Free resources allocated by open_map (CTXT). */
511 close_map (struct read_map_ctxt *ctxt)
513 #ifdef USE_LDR_ROUTINES
514 ldr_xdetach (ctxt->proc);
518 /* target_so_ops callback. Return a list of shared objects currently loaded
521 static struct so_list *
522 osf_current_sos (void)
524 struct so_list *head = NULL, *tail, *newtail, so;
525 struct read_map_ctxt ctxt;
528 if (!open_map (&ctxt))
531 /* Read subsequent elements. */
532 for (skipped_main = 0;;)
534 if (!read_map (&ctxt, &so))
537 /* Skip the main program module, which is first in the list after
539 if (!so.lm_info->isloader && !skipped_main)
546 newtail = xmalloc (sizeof *newtail);
550 tail->next = newtail;
553 memcpy (tail, &so, sizeof so);
562 /* target_so_ops callback. Attempt to locate and open the main symbol
566 osf_open_symbol_file_object (void *from_ttyp)
568 struct read_map_ctxt ctxt;
573 if (!query ("Attempt to reload symbols from process? "))
576 /* The first module after /sbin/loader is the main program. */
577 if (!open_map (&ctxt))
579 for (found = 0; !found;)
581 if (!read_map (&ctxt, &so))
583 found = !so.lm_info->isloader;
589 symbol_file_add_main (so.so_name, *(int *) from_ttyp);
593 /* target_so_ops callback. Return whether PC is in the dynamic linker. */
596 osf_in_dynsym_resolve_code (CORE_ADDR pc)
598 /* This function currently always return False. This is a temporary
599 solution which only consequence is to introduce a minor incovenience
600 for the user: When stepping inside a subprogram located in a shared
601 library, gdb might stop inside the dynamic loader code instead of
602 inside the subprogram itself. See the explanations in infrun.c about
603 the IN_SOLIB_DYNSYM_RESOLVE_CODE macro for more details. */
607 static struct target_so_ops osf_so_ops;
610 _initialize_osf_solib (void)
612 osf_so_ops.relocate_section_addresses = osf_relocate_section_addresses;
613 osf_so_ops.free_so = osf_free_so;
614 osf_so_ops.clear_solib = osf_clear_solib;
615 osf_so_ops.solib_create_inferior_hook = osf_solib_create_inferior_hook;
616 osf_so_ops.special_symbol_handling = osf_special_symbol_handling;
617 osf_so_ops.current_sos = osf_current_sos;
618 osf_so_ops.open_symbol_file_object = osf_open_symbol_file_object;
619 osf_so_ops.in_dynsym_resolve_code = osf_in_dynsym_resolve_code;
621 /* FIXME: Don't do this here. *_gdbarch_init() should set so_ops. */
622 current_target_so_ops = &osf_so_ops;