| 1 | /* Handle SunOS and SVR4 shared libraries for GDB, the GNU Debugger. |
| 2 | Copyright 1990, 91, 92, 93, 94, 95, 96, 98, 1999 |
| 3 | Free Software Foundation, Inc. |
| 4 | |
| 5 | This file is part of GDB. |
| 6 | |
| 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 2 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 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. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with this program; if not, write to the Free Software |
| 19 | Foundation, Inc., 59 Temple Place - Suite 330, |
| 20 | Boston, MA 02111-1307, USA. */ |
| 21 | |
| 22 | |
| 23 | #include "defs.h" |
| 24 | |
| 25 | /* This file is only compilable if link.h is available. */ |
| 26 | |
| 27 | #ifdef HAVE_LINK_H |
| 28 | |
| 29 | #include <sys/types.h> |
| 30 | #include <signal.h> |
| 31 | #include "gdb_string.h" |
| 32 | #include <sys/param.h> |
| 33 | #include <fcntl.h> |
| 34 | |
| 35 | #ifndef SVR4_SHARED_LIBS |
| 36 | /* SunOS shared libs need the nlist structure. */ |
| 37 | #include <a.out.h> |
| 38 | #else |
| 39 | #include "elf/external.h" |
| 40 | #endif |
| 41 | |
| 42 | #include <link.h> |
| 43 | |
| 44 | #include "symtab.h" |
| 45 | #include "bfd.h" |
| 46 | #include "symfile.h" |
| 47 | #include "objfiles.h" |
| 48 | #include "gdbcore.h" |
| 49 | #include "command.h" |
| 50 | #include "target.h" |
| 51 | #include "frame.h" |
| 52 | #include "gnu-regex.h" |
| 53 | #include "inferior.h" |
| 54 | #include "environ.h" |
| 55 | #include "language.h" |
| 56 | #include "gdbcmd.h" |
| 57 | |
| 58 | #define MAX_PATH_SIZE 512 /* FIXME: Should be dynamic */ |
| 59 | |
| 60 | /* On SVR4 systems, a list of symbols in the dynamic linker where |
| 61 | GDB can try to place a breakpoint to monitor shared library |
| 62 | events. |
| 63 | |
| 64 | If none of these symbols are found, or other errors occur, then |
| 65 | SVR4 systems will fall back to using a symbol as the "startup |
| 66 | mapping complete" breakpoint address. */ |
| 67 | |
| 68 | #ifdef SVR4_SHARED_LIBS |
| 69 | static char *solib_break_names[] = |
| 70 | { |
| 71 | "r_debug_state", |
| 72 | "_r_debug_state", |
| 73 | "_dl_debug_state", |
| 74 | "rtld_db_dlactivity", |
| 75 | NULL |
| 76 | }; |
| 77 | #endif |
| 78 | |
| 79 | #define BKPT_AT_SYMBOL 1 |
| 80 | |
| 81 | #if defined (BKPT_AT_SYMBOL) && defined (SVR4_SHARED_LIBS) |
| 82 | static char *bkpt_names[] = |
| 83 | { |
| 84 | #ifdef SOLIB_BKPT_NAME |
| 85 | SOLIB_BKPT_NAME, /* Prefer configured name if it exists. */ |
| 86 | #endif |
| 87 | "_start", |
| 88 | "main", |
| 89 | NULL |
| 90 | }; |
| 91 | #endif |
| 92 | |
| 93 | /* Symbols which are used to locate the base of the link map structures. */ |
| 94 | |
| 95 | #ifndef SVR4_SHARED_LIBS |
| 96 | static char *debug_base_symbols[] = |
| 97 | { |
| 98 | "_DYNAMIC", |
| 99 | "_DYNAMIC__MGC", |
| 100 | NULL |
| 101 | }; |
| 102 | #endif |
| 103 | |
| 104 | static char *main_name_list[] = |
| 105 | { |
| 106 | "main_$main", |
| 107 | NULL |
| 108 | }; |
| 109 | |
| 110 | /* local data declarations */ |
| 111 | |
| 112 | #ifndef SVR4_SHARED_LIBS |
| 113 | |
| 114 | #define LM_ADDR(so) ((so) -> lm.lm_addr) |
| 115 | #define LM_NEXT(so) ((so) -> lm.lm_next) |
| 116 | #define LM_NAME(so) ((so) -> lm.lm_name) |
| 117 | /* Test for first link map entry; first entry is a shared library. */ |
| 118 | #define IGNORE_FIRST_LINK_MAP_ENTRY(x) (0) |
| 119 | static struct link_dynamic dynamic_copy; |
| 120 | static struct link_dynamic_2 ld_2_copy; |
| 121 | static struct ld_debug debug_copy; |
| 122 | static CORE_ADDR debug_addr; |
| 123 | static CORE_ADDR flag_addr; |
| 124 | |
| 125 | #else /* SVR4_SHARED_LIBS */ |
| 126 | |
| 127 | #define LM_ADDR(so) ((so) -> lm.l_addr) |
| 128 | #define LM_NEXT(so) ((so) -> lm.l_next) |
| 129 | #define LM_NAME(so) ((so) -> lm.l_name) |
| 130 | /* Test for first link map entry; first entry is the exec-file. */ |
| 131 | #define IGNORE_FIRST_LINK_MAP_ENTRY(x) ((x).l_prev == NULL) |
| 132 | static struct r_debug debug_copy; |
| 133 | char shadow_contents[BREAKPOINT_MAX]; /* Stash old bkpt addr contents */ |
| 134 | |
| 135 | #endif /* !SVR4_SHARED_LIBS */ |
| 136 | |
| 137 | struct so_list |
| 138 | { |
| 139 | struct so_list *next; /* next structure in linked list */ |
| 140 | struct link_map lm; /* copy of link map from inferior */ |
| 141 | struct link_map *lmaddr; /* addr in inferior lm was read from */ |
| 142 | CORE_ADDR lmend; /* upper addr bound of mapped object */ |
| 143 | char so_name[MAX_PATH_SIZE]; /* shared object lib name (FIXME) */ |
| 144 | char symbols_loaded; /* flag: symbols read in yet? */ |
| 145 | char from_tty; /* flag: print msgs? */ |
| 146 | struct objfile *objfile; /* objfile for loaded lib */ |
| 147 | struct section_table *sections; |
| 148 | struct section_table *sections_end; |
| 149 | struct section_table *textsection; |
| 150 | bfd *abfd; |
| 151 | }; |
| 152 | |
| 153 | static struct so_list *so_list_head; /* List of known shared objects */ |
| 154 | static CORE_ADDR debug_base; /* Base of dynamic linker structures */ |
| 155 | static CORE_ADDR breakpoint_addr; /* Address where end bkpt is set */ |
| 156 | |
| 157 | static int solib_cleanup_queued = 0; /* make_run_cleanup called */ |
| 158 | |
| 159 | extern int |
| 160 | fdmatch PARAMS ((int, int)); /* In libiberty */ |
| 161 | |
| 162 | /* Local function prototypes */ |
| 163 | |
| 164 | static void |
| 165 | do_clear_solib PARAMS ((PTR)); |
| 166 | |
| 167 | static int |
| 168 | match_main PARAMS ((char *)); |
| 169 | |
| 170 | static void |
| 171 | special_symbol_handling PARAMS ((struct so_list *)); |
| 172 | |
| 173 | static void |
| 174 | sharedlibrary_command PARAMS ((char *, int)); |
| 175 | |
| 176 | static int |
| 177 | enable_break PARAMS ((void)); |
| 178 | |
| 179 | static void |
| 180 | info_sharedlibrary_command PARAMS ((char *, int)); |
| 181 | |
| 182 | static int symbol_add_stub PARAMS ((PTR)); |
| 183 | |
| 184 | static struct so_list * |
| 185 | find_solib PARAMS ((struct so_list *)); |
| 186 | |
| 187 | static struct link_map * |
| 188 | first_link_map_member PARAMS ((void)); |
| 189 | |
| 190 | static CORE_ADDR |
| 191 | locate_base PARAMS ((void)); |
| 192 | |
| 193 | static int solib_map_sections PARAMS ((PTR)); |
| 194 | |
| 195 | #ifdef SVR4_SHARED_LIBS |
| 196 | |
| 197 | static CORE_ADDR |
| 198 | elf_locate_base PARAMS ((void)); |
| 199 | |
| 200 | #else |
| 201 | |
| 202 | static int |
| 203 | disable_break PARAMS ((void)); |
| 204 | |
| 205 | static void |
| 206 | allocate_rt_common_objfile PARAMS ((void)); |
| 207 | |
| 208 | static void |
| 209 | solib_add_common_symbols PARAMS ((struct rtc_symb *)); |
| 210 | |
| 211 | #endif |
| 212 | |
| 213 | void _initialize_solib PARAMS ((void)); |
| 214 | |
| 215 | /* If non-zero, this is a prefix that will be added to the front of the name |
| 216 | shared libraries with an absolute filename for loading. */ |
| 217 | static char *solib_absolute_prefix = NULL; |
| 218 | |
| 219 | /* If non-empty, this is a search path for loading non-absolute shared library |
| 220 | symbol files. This takes precedence over the environment variables PATH |
| 221 | and LD_LIBRARY_PATH. */ |
| 222 | static char *solib_search_path = NULL; |
| 223 | |
| 224 | /* |
| 225 | |
| 226 | LOCAL FUNCTION |
| 227 | |
| 228 | solib_map_sections -- open bfd and build sections for shared lib |
| 229 | |
| 230 | SYNOPSIS |
| 231 | |
| 232 | static int solib_map_sections (struct so_list *so) |
| 233 | |
| 234 | DESCRIPTION |
| 235 | |
| 236 | Given a pointer to one of the shared objects in our list |
| 237 | of mapped objects, use the recorded name to open a bfd |
| 238 | descriptor for the object, build a section table, and then |
| 239 | relocate all the section addresses by the base address at |
| 240 | which the shared object was mapped. |
| 241 | |
| 242 | FIXMES |
| 243 | |
| 244 | In most (all?) cases the shared object file name recorded in the |
| 245 | dynamic linkage tables will be a fully qualified pathname. For |
| 246 | cases where it isn't, do we really mimic the systems search |
| 247 | mechanism correctly in the below code (particularly the tilde |
| 248 | expansion stuff?). |
| 249 | */ |
| 250 | |
| 251 | static int |
| 252 | solib_map_sections (arg) |
| 253 | PTR arg; |
| 254 | { |
| 255 | struct so_list *so = (struct so_list *) arg; /* catch_errors bogon */ |
| 256 | char *filename; |
| 257 | char *scratch_pathname; |
| 258 | int scratch_chan; |
| 259 | struct section_table *p; |
| 260 | struct cleanup *old_chain; |
| 261 | bfd *abfd; |
| 262 | |
| 263 | filename = tilde_expand (so->so_name); |
| 264 | |
| 265 | if (solib_absolute_prefix && ROOTED_P (filename)) |
| 266 | /* Prefix shared libraries with absolute filenames with |
| 267 | SOLIB_ABSOLUTE_PREFIX. */ |
| 268 | { |
| 269 | char *pfxed_fn; |
| 270 | int pfx_len; |
| 271 | |
| 272 | pfx_len = strlen (solib_absolute_prefix); |
| 273 | |
| 274 | /* Remove trailing slashes. */ |
| 275 | while (pfx_len > 0 && SLASH_P (solib_absolute_prefix[pfx_len - 1])) |
| 276 | pfx_len--; |
| 277 | |
| 278 | pfxed_fn = xmalloc (pfx_len + strlen (filename) + 1); |
| 279 | strcpy (pfxed_fn, solib_absolute_prefix); |
| 280 | strcat (pfxed_fn, filename); |
| 281 | free (filename); |
| 282 | |
| 283 | filename = pfxed_fn; |
| 284 | } |
| 285 | |
| 286 | old_chain = make_cleanup (free, filename); |
| 287 | |
| 288 | scratch_chan = -1; |
| 289 | |
| 290 | if (solib_search_path) |
| 291 | scratch_chan = openp (solib_search_path, |
| 292 | 1, filename, O_RDONLY, 0, &scratch_pathname); |
| 293 | if (scratch_chan < 0) |
| 294 | scratch_chan = openp (get_in_environ (inferior_environ, "PATH"), |
| 295 | 1, filename, O_RDONLY, 0, &scratch_pathname); |
| 296 | if (scratch_chan < 0) |
| 297 | { |
| 298 | scratch_chan = openp (get_in_environ |
| 299 | (inferior_environ, "LD_LIBRARY_PATH"), |
| 300 | 1, filename, O_RDONLY, 0, &scratch_pathname); |
| 301 | } |
| 302 | if (scratch_chan < 0) |
| 303 | { |
| 304 | perror_with_name (filename); |
| 305 | } |
| 306 | /* Leave scratch_pathname allocated. abfd->name will point to it. */ |
| 307 | |
| 308 | abfd = bfd_fdopenr (scratch_pathname, gnutarget, scratch_chan); |
| 309 | if (!abfd) |
| 310 | { |
| 311 | close (scratch_chan); |
| 312 | error ("Could not open `%s' as an executable file: %s", |
| 313 | scratch_pathname, bfd_errmsg (bfd_get_error ())); |
| 314 | } |
| 315 | /* Leave bfd open, core_xfer_memory and "info files" need it. */ |
| 316 | so->abfd = abfd; |
| 317 | abfd->cacheable = true; |
| 318 | |
| 319 | /* copy full path name into so_name, so that later symbol_file_add can find |
| 320 | it */ |
| 321 | if (strlen (scratch_pathname) >= MAX_PATH_SIZE) |
| 322 | error ("Full path name length of shared library exceeds MAX_PATH_SIZE in so_list structure."); |
| 323 | strcpy (so->so_name, scratch_pathname); |
| 324 | |
| 325 | if (!bfd_check_format (abfd, bfd_object)) |
| 326 | { |
| 327 | error ("\"%s\": not in executable format: %s.", |
| 328 | scratch_pathname, bfd_errmsg (bfd_get_error ())); |
| 329 | } |
| 330 | if (build_section_table (abfd, &so->sections, &so->sections_end)) |
| 331 | { |
| 332 | error ("Can't find the file sections in `%s': %s", |
| 333 | bfd_get_filename (abfd), bfd_errmsg (bfd_get_error ())); |
| 334 | } |
| 335 | |
| 336 | for (p = so->sections; p < so->sections_end; p++) |
| 337 | { |
| 338 | /* Relocate the section binding addresses as recorded in the shared |
| 339 | object's file by the base address to which the object was actually |
| 340 | mapped. */ |
| 341 | p->addr += (CORE_ADDR) LM_ADDR (so); |
| 342 | p->endaddr += (CORE_ADDR) LM_ADDR (so); |
| 343 | so->lmend = (CORE_ADDR) max (p->endaddr, so->lmend); |
| 344 | if (STREQ (p->the_bfd_section->name, ".text")) |
| 345 | { |
| 346 | so->textsection = p; |
| 347 | } |
| 348 | } |
| 349 | |
| 350 | /* Free the file names, close the file now. */ |
| 351 | do_cleanups (old_chain); |
| 352 | |
| 353 | return (1); |
| 354 | } |
| 355 | |
| 356 | #ifndef SVR4_SHARED_LIBS |
| 357 | |
| 358 | /* Allocate the runtime common object file. */ |
| 359 | |
| 360 | static void |
| 361 | allocate_rt_common_objfile () |
| 362 | { |
| 363 | struct objfile *objfile; |
| 364 | struct objfile *last_one; |
| 365 | |
| 366 | objfile = (struct objfile *) xmalloc (sizeof (struct objfile)); |
| 367 | memset (objfile, 0, sizeof (struct objfile)); |
| 368 | objfile->md = NULL; |
| 369 | obstack_specify_allocation (&objfile->psymbol_cache.cache, 0, 0, |
| 370 | xmalloc, free); |
| 371 | obstack_specify_allocation (&objfile->psymbol_obstack, 0, 0, xmalloc, |
| 372 | free); |
| 373 | obstack_specify_allocation (&objfile->symbol_obstack, 0, 0, xmalloc, |
| 374 | free); |
| 375 | obstack_specify_allocation (&objfile->type_obstack, 0, 0, xmalloc, |
| 376 | free); |
| 377 | objfile->name = mstrsave (objfile->md, "rt_common"); |
| 378 | |
| 379 | /* Add this file onto the tail of the linked list of other such files. */ |
| 380 | |
| 381 | objfile->next = NULL; |
| 382 | if (object_files == NULL) |
| 383 | object_files = objfile; |
| 384 | else |
| 385 | { |
| 386 | for (last_one = object_files; |
| 387 | last_one->next; |
| 388 | last_one = last_one->next); |
| 389 | last_one->next = objfile; |
| 390 | } |
| 391 | |
| 392 | rt_common_objfile = objfile; |
| 393 | } |
| 394 | |
| 395 | /* Read all dynamically loaded common symbol definitions from the inferior |
| 396 | and put them into the minimal symbol table for the runtime common |
| 397 | objfile. */ |
| 398 | |
| 399 | static void |
| 400 | solib_add_common_symbols (rtc_symp) |
| 401 | struct rtc_symb *rtc_symp; |
| 402 | { |
| 403 | struct rtc_symb inferior_rtc_symb; |
| 404 | struct nlist inferior_rtc_nlist; |
| 405 | int len; |
| 406 | char *name; |
| 407 | |
| 408 | /* Remove any runtime common symbols from previous runs. */ |
| 409 | |
| 410 | if (rt_common_objfile != NULL && rt_common_objfile->minimal_symbol_count) |
| 411 | { |
| 412 | obstack_free (&rt_common_objfile->symbol_obstack, 0); |
| 413 | obstack_specify_allocation (&rt_common_objfile->symbol_obstack, 0, 0, |
| 414 | xmalloc, free); |
| 415 | rt_common_objfile->minimal_symbol_count = 0; |
| 416 | rt_common_objfile->msymbols = NULL; |
| 417 | } |
| 418 | |
| 419 | init_minimal_symbol_collection (); |
| 420 | make_cleanup ((make_cleanup_func) discard_minimal_symbols, 0); |
| 421 | |
| 422 | while (rtc_symp) |
| 423 | { |
| 424 | read_memory ((CORE_ADDR) rtc_symp, |
| 425 | (char *) &inferior_rtc_symb, |
| 426 | sizeof (inferior_rtc_symb)); |
| 427 | read_memory ((CORE_ADDR) inferior_rtc_symb.rtc_sp, |
| 428 | (char *) &inferior_rtc_nlist, |
| 429 | sizeof (inferior_rtc_nlist)); |
| 430 | if (inferior_rtc_nlist.n_type == N_COMM) |
| 431 | { |
| 432 | /* FIXME: The length of the symbol name is not available, but in the |
| 433 | current implementation the common symbol is allocated immediately |
| 434 | behind the name of the symbol. */ |
| 435 | len = inferior_rtc_nlist.n_value - inferior_rtc_nlist.n_un.n_strx; |
| 436 | |
| 437 | name = xmalloc (len); |
| 438 | read_memory ((CORE_ADDR) inferior_rtc_nlist.n_un.n_name, name, len); |
| 439 | |
| 440 | /* Allocate the runtime common objfile if necessary. */ |
| 441 | if (rt_common_objfile == NULL) |
| 442 | allocate_rt_common_objfile (); |
| 443 | |
| 444 | prim_record_minimal_symbol (name, inferior_rtc_nlist.n_value, |
| 445 | mst_bss, rt_common_objfile); |
| 446 | free (name); |
| 447 | } |
| 448 | rtc_symp = inferior_rtc_symb.rtc_next; |
| 449 | } |
| 450 | |
| 451 | /* Install any minimal symbols that have been collected as the current |
| 452 | minimal symbols for the runtime common objfile. */ |
| 453 | |
| 454 | install_minimal_symbols (rt_common_objfile); |
| 455 | } |
| 456 | |
| 457 | #endif /* SVR4_SHARED_LIBS */ |
| 458 | |
| 459 | |
| 460 | #ifdef SVR4_SHARED_LIBS |
| 461 | |
| 462 | static CORE_ADDR |
| 463 | bfd_lookup_symbol PARAMS ((bfd *, char *)); |
| 464 | |
| 465 | /* |
| 466 | |
| 467 | LOCAL FUNCTION |
| 468 | |
| 469 | bfd_lookup_symbol -- lookup the value for a specific symbol |
| 470 | |
| 471 | SYNOPSIS |
| 472 | |
| 473 | CORE_ADDR bfd_lookup_symbol (bfd *abfd, char *symname) |
| 474 | |
| 475 | DESCRIPTION |
| 476 | |
| 477 | An expensive way to lookup the value of a single symbol for |
| 478 | bfd's that are only temporary anyway. This is used by the |
| 479 | shared library support to find the address of the debugger |
| 480 | interface structures in the shared library. |
| 481 | |
| 482 | Note that 0 is specifically allowed as an error return (no |
| 483 | such symbol). |
| 484 | */ |
| 485 | |
| 486 | static CORE_ADDR |
| 487 | bfd_lookup_symbol (abfd, symname) |
| 488 | bfd *abfd; |
| 489 | char *symname; |
| 490 | { |
| 491 | unsigned int storage_needed; |
| 492 | asymbol *sym; |
| 493 | asymbol **symbol_table; |
| 494 | unsigned int number_of_symbols; |
| 495 | unsigned int i; |
| 496 | struct cleanup *back_to; |
| 497 | CORE_ADDR symaddr = 0; |
| 498 | |
| 499 | storage_needed = bfd_get_symtab_upper_bound (abfd); |
| 500 | |
| 501 | if (storage_needed > 0) |
| 502 | { |
| 503 | symbol_table = (asymbol **) xmalloc (storage_needed); |
| 504 | back_to = make_cleanup (free, (PTR) symbol_table); |
| 505 | number_of_symbols = bfd_canonicalize_symtab (abfd, symbol_table); |
| 506 | |
| 507 | for (i = 0; i < number_of_symbols; i++) |
| 508 | { |
| 509 | sym = *symbol_table++; |
| 510 | if (STREQ (sym->name, symname)) |
| 511 | { |
| 512 | /* Bfd symbols are section relative. */ |
| 513 | symaddr = sym->value + sym->section->vma; |
| 514 | break; |
| 515 | } |
| 516 | } |
| 517 | do_cleanups (back_to); |
| 518 | } |
| 519 | return (symaddr); |
| 520 | } |
| 521 | |
| 522 | #ifdef HANDLE_SVR4_EXEC_EMULATORS |
| 523 | |
| 524 | /* |
| 525 | Solaris BCP (the part of Solaris which allows it to run SunOS4 |
| 526 | a.out files) throws in another wrinkle. Solaris does not fill |
| 527 | in the usual a.out link map structures when running BCP programs, |
| 528 | the only way to get at them is via groping around in the dynamic |
| 529 | linker. |
| 530 | The dynamic linker and it's structures are located in the shared |
| 531 | C library, which gets run as the executable's "interpreter" by |
| 532 | the kernel. |
| 533 | |
| 534 | Note that we can assume nothing about the process state at the time |
| 535 | we need to find these structures. We may be stopped on the first |
| 536 | instruction of the interpreter (C shared library), the first |
| 537 | instruction of the executable itself, or somewhere else entirely |
| 538 | (if we attached to the process for example). |
| 539 | */ |
| 540 | |
| 541 | static char *debug_base_symbols[] = |
| 542 | { |
| 543 | "r_debug", /* Solaris 2.3 */ |
| 544 | "_r_debug", /* Solaris 2.1, 2.2 */ |
| 545 | NULL |
| 546 | }; |
| 547 | |
| 548 | static int |
| 549 | look_for_base PARAMS ((int, CORE_ADDR)); |
| 550 | |
| 551 | /* |
| 552 | |
| 553 | LOCAL FUNCTION |
| 554 | |
| 555 | look_for_base -- examine file for each mapped address segment |
| 556 | |
| 557 | SYNOPSYS |
| 558 | |
| 559 | static int look_for_base (int fd, CORE_ADDR baseaddr) |
| 560 | |
| 561 | DESCRIPTION |
| 562 | |
| 563 | This function is passed to proc_iterate_over_mappings, which |
| 564 | causes it to get called once for each mapped address space, with |
| 565 | an open file descriptor for the file mapped to that space, and the |
| 566 | base address of that mapped space. |
| 567 | |
| 568 | Our job is to find the debug base symbol in the file that this |
| 569 | fd is open on, if it exists, and if so, initialize the dynamic |
| 570 | linker structure base address debug_base. |
| 571 | |
| 572 | Note that this is a computationally expensive proposition, since |
| 573 | we basically have to open a bfd on every call, so we specifically |
| 574 | avoid opening the exec file. |
| 575 | */ |
| 576 | |
| 577 | static int |
| 578 | look_for_base (fd, baseaddr) |
| 579 | int fd; |
| 580 | CORE_ADDR baseaddr; |
| 581 | { |
| 582 | bfd *interp_bfd; |
| 583 | CORE_ADDR address = 0; |
| 584 | char **symbolp; |
| 585 | |
| 586 | /* If the fd is -1, then there is no file that corresponds to this |
| 587 | mapped memory segment, so skip it. Also, if the fd corresponds |
| 588 | to the exec file, skip it as well. */ |
| 589 | |
| 590 | if (fd == -1 |
| 591 | || (exec_bfd != NULL |
| 592 | && fdmatch (fileno ((FILE *) (exec_bfd->iostream)), fd))) |
| 593 | { |
| 594 | return (0); |
| 595 | } |
| 596 | |
| 597 | /* Try to open whatever random file this fd corresponds to. Note that |
| 598 | we have no way currently to find the filename. Don't gripe about |
| 599 | any problems we might have, just fail. */ |
| 600 | |
| 601 | if ((interp_bfd = bfd_fdopenr ("unnamed", gnutarget, fd)) == NULL) |
| 602 | { |
| 603 | return (0); |
| 604 | } |
| 605 | if (!bfd_check_format (interp_bfd, bfd_object)) |
| 606 | { |
| 607 | /* FIXME-leak: on failure, might not free all memory associated with |
| 608 | interp_bfd. */ |
| 609 | bfd_close (interp_bfd); |
| 610 | return (0); |
| 611 | } |
| 612 | |
| 613 | /* Now try to find our debug base symbol in this file, which we at |
| 614 | least know to be a valid ELF executable or shared library. */ |
| 615 | |
| 616 | for (symbolp = debug_base_symbols; *symbolp != NULL; symbolp++) |
| 617 | { |
| 618 | address = bfd_lookup_symbol (interp_bfd, *symbolp); |
| 619 | if (address != 0) |
| 620 | { |
| 621 | break; |
| 622 | } |
| 623 | } |
| 624 | if (address == 0) |
| 625 | { |
| 626 | /* FIXME-leak: on failure, might not free all memory associated with |
| 627 | interp_bfd. */ |
| 628 | bfd_close (interp_bfd); |
| 629 | return (0); |
| 630 | } |
| 631 | |
| 632 | /* Eureka! We found the symbol. But now we may need to relocate it |
| 633 | by the base address. If the symbol's value is less than the base |
| 634 | address of the shared library, then it hasn't yet been relocated |
| 635 | by the dynamic linker, and we have to do it ourself. FIXME: Note |
| 636 | that we make the assumption that the first segment that corresponds |
| 637 | to the shared library has the base address to which the library |
| 638 | was relocated. */ |
| 639 | |
| 640 | if (address < baseaddr) |
| 641 | { |
| 642 | address += baseaddr; |
| 643 | } |
| 644 | debug_base = address; |
| 645 | /* FIXME-leak: on failure, might not free all memory associated with |
| 646 | interp_bfd. */ |
| 647 | bfd_close (interp_bfd); |
| 648 | return (1); |
| 649 | } |
| 650 | #endif /* HANDLE_SVR4_EXEC_EMULATORS */ |
| 651 | |
| 652 | /* |
| 653 | |
| 654 | LOCAL FUNCTION |
| 655 | |
| 656 | elf_locate_base -- locate the base address of dynamic linker structs |
| 657 | for SVR4 elf targets. |
| 658 | |
| 659 | SYNOPSIS |
| 660 | |
| 661 | CORE_ADDR elf_locate_base (void) |
| 662 | |
| 663 | DESCRIPTION |
| 664 | |
| 665 | For SVR4 elf targets the address of the dynamic linker's runtime |
| 666 | structure is contained within the dynamic info section in the |
| 667 | executable file. The dynamic section is also mapped into the |
| 668 | inferior address space. Because the runtime loader fills in the |
| 669 | real address before starting the inferior, we have to read in the |
| 670 | dynamic info section from the inferior address space. |
| 671 | If there are any errors while trying to find the address, we |
| 672 | silently return 0, otherwise the found address is returned. |
| 673 | |
| 674 | */ |
| 675 | |
| 676 | static CORE_ADDR |
| 677 | elf_locate_base () |
| 678 | { |
| 679 | sec_ptr dyninfo_sect; |
| 680 | int dyninfo_sect_size; |
| 681 | CORE_ADDR dyninfo_addr; |
| 682 | char *buf; |
| 683 | char *bufend; |
| 684 | |
| 685 | /* Find the start address of the .dynamic section. */ |
| 686 | dyninfo_sect = bfd_get_section_by_name (exec_bfd, ".dynamic"); |
| 687 | if (dyninfo_sect == NULL) |
| 688 | return 0; |
| 689 | dyninfo_addr = bfd_section_vma (exec_bfd, dyninfo_sect); |
| 690 | |
| 691 | /* Read in .dynamic section, silently ignore errors. */ |
| 692 | dyninfo_sect_size = bfd_section_size (exec_bfd, dyninfo_sect); |
| 693 | buf = alloca (dyninfo_sect_size); |
| 694 | if (target_read_memory (dyninfo_addr, buf, dyninfo_sect_size)) |
| 695 | return 0; |
| 696 | |
| 697 | /* Find the DT_DEBUG entry in the the .dynamic section. |
| 698 | For mips elf we look for DT_MIPS_RLD_MAP, mips elf apparently has |
| 699 | no DT_DEBUG entries. */ |
| 700 | #ifndef TARGET_ELF64 |
| 701 | for (bufend = buf + dyninfo_sect_size; |
| 702 | buf < bufend; |
| 703 | buf += sizeof (Elf32_External_Dyn)) |
| 704 | { |
| 705 | Elf32_External_Dyn *x_dynp = (Elf32_External_Dyn *) buf; |
| 706 | long dyn_tag; |
| 707 | CORE_ADDR dyn_ptr; |
| 708 | |
| 709 | dyn_tag = bfd_h_get_32 (exec_bfd, (bfd_byte *) x_dynp->d_tag); |
| 710 | if (dyn_tag == DT_NULL) |
| 711 | break; |
| 712 | else if (dyn_tag == DT_DEBUG) |
| 713 | { |
| 714 | dyn_ptr = bfd_h_get_32 (exec_bfd, (bfd_byte *) x_dynp->d_un.d_ptr); |
| 715 | return dyn_ptr; |
| 716 | } |
| 717 | #ifdef DT_MIPS_RLD_MAP |
| 718 | else if (dyn_tag == DT_MIPS_RLD_MAP) |
| 719 | { |
| 720 | char pbuf[TARGET_PTR_BIT / HOST_CHAR_BIT]; |
| 721 | |
| 722 | /* DT_MIPS_RLD_MAP contains a pointer to the address |
| 723 | of the dynamic link structure. */ |
| 724 | dyn_ptr = bfd_h_get_32 (exec_bfd, (bfd_byte *) x_dynp->d_un.d_ptr); |
| 725 | if (target_read_memory (dyn_ptr, pbuf, sizeof (pbuf))) |
| 726 | return 0; |
| 727 | return extract_unsigned_integer (pbuf, sizeof (pbuf)); |
| 728 | } |
| 729 | #endif |
| 730 | } |
| 731 | #else /* ELF64 */ |
| 732 | for (bufend = buf + dyninfo_sect_size; |
| 733 | buf < bufend; |
| 734 | buf += sizeof (Elf64_External_Dyn)) |
| 735 | { |
| 736 | Elf64_External_Dyn *x_dynp = (Elf64_External_Dyn *) buf; |
| 737 | long dyn_tag; |
| 738 | CORE_ADDR dyn_ptr; |
| 739 | |
| 740 | dyn_tag = bfd_h_get_64 (exec_bfd, (bfd_byte *) x_dynp->d_tag); |
| 741 | if (dyn_tag == DT_NULL) |
| 742 | break; |
| 743 | else if (dyn_tag == DT_DEBUG) |
| 744 | { |
| 745 | dyn_ptr = bfd_h_get_64 (exec_bfd, (bfd_byte *) x_dynp->d_un.d_ptr); |
| 746 | return dyn_ptr; |
| 747 | } |
| 748 | } |
| 749 | #endif |
| 750 | |
| 751 | /* DT_DEBUG entry not found. */ |
| 752 | return 0; |
| 753 | } |
| 754 | |
| 755 | #endif /* SVR4_SHARED_LIBS */ |
| 756 | |
| 757 | /* |
| 758 | |
| 759 | LOCAL FUNCTION |
| 760 | |
| 761 | locate_base -- locate the base address of dynamic linker structs |
| 762 | |
| 763 | SYNOPSIS |
| 764 | |
| 765 | CORE_ADDR locate_base (void) |
| 766 | |
| 767 | DESCRIPTION |
| 768 | |
| 769 | For both the SunOS and SVR4 shared library implementations, if the |
| 770 | inferior executable has been linked dynamically, there is a single |
| 771 | address somewhere in the inferior's data space which is the key to |
| 772 | locating all of the dynamic linker's runtime structures. This |
| 773 | address is the value of the debug base symbol. The job of this |
| 774 | function is to find and return that address, or to return 0 if there |
| 775 | is no such address (the executable is statically linked for example). |
| 776 | |
| 777 | For SunOS, the job is almost trivial, since the dynamic linker and |
| 778 | all of it's structures are statically linked to the executable at |
| 779 | link time. Thus the symbol for the address we are looking for has |
| 780 | already been added to the minimal symbol table for the executable's |
| 781 | objfile at the time the symbol file's symbols were read, and all we |
| 782 | have to do is look it up there. Note that we explicitly do NOT want |
| 783 | to find the copies in the shared library. |
| 784 | |
| 785 | The SVR4 version is a bit more complicated because the address |
| 786 | is contained somewhere in the dynamic info section. We have to go |
| 787 | to a lot more work to discover the address of the debug base symbol. |
| 788 | Because of this complexity, we cache the value we find and return that |
| 789 | value on subsequent invocations. Note there is no copy in the |
| 790 | executable symbol tables. |
| 791 | |
| 792 | */ |
| 793 | |
| 794 | static CORE_ADDR |
| 795 | locate_base () |
| 796 | { |
| 797 | |
| 798 | #ifndef SVR4_SHARED_LIBS |
| 799 | |
| 800 | struct minimal_symbol *msymbol; |
| 801 | CORE_ADDR address = 0; |
| 802 | char **symbolp; |
| 803 | |
| 804 | /* For SunOS, we want to limit the search for the debug base symbol to the |
| 805 | executable being debugged, since there is a duplicate named symbol in the |
| 806 | shared library. We don't want the shared library versions. */ |
| 807 | |
| 808 | for (symbolp = debug_base_symbols; *symbolp != NULL; symbolp++) |
| 809 | { |
| 810 | msymbol = lookup_minimal_symbol (*symbolp, NULL, symfile_objfile); |
| 811 | if ((msymbol != NULL) && (SYMBOL_VALUE_ADDRESS (msymbol) != 0)) |
| 812 | { |
| 813 | address = SYMBOL_VALUE_ADDRESS (msymbol); |
| 814 | return (address); |
| 815 | } |
| 816 | } |
| 817 | return (0); |
| 818 | |
| 819 | #else /* SVR4_SHARED_LIBS */ |
| 820 | |
| 821 | /* Check to see if we have a currently valid address, and if so, avoid |
| 822 | doing all this work again and just return the cached address. If |
| 823 | we have no cached address, try to locate it in the dynamic info |
| 824 | section for ELF executables. */ |
| 825 | |
| 826 | if (debug_base == 0) |
| 827 | { |
| 828 | if (exec_bfd != NULL |
| 829 | && bfd_get_flavour (exec_bfd) == bfd_target_elf_flavour) |
| 830 | debug_base = elf_locate_base (); |
| 831 | #ifdef HANDLE_SVR4_EXEC_EMULATORS |
| 832 | /* Try it the hard way for emulated executables. */ |
| 833 | else if (inferior_pid != 0 && target_has_execution) |
| 834 | proc_iterate_over_mappings (look_for_base); |
| 835 | #endif |
| 836 | } |
| 837 | return (debug_base); |
| 838 | |
| 839 | #endif /* !SVR4_SHARED_LIBS */ |
| 840 | |
| 841 | } |
| 842 | |
| 843 | /* |
| 844 | |
| 845 | LOCAL FUNCTION |
| 846 | |
| 847 | first_link_map_member -- locate first member in dynamic linker's map |
| 848 | |
| 849 | SYNOPSIS |
| 850 | |
| 851 | static struct link_map *first_link_map_member (void) |
| 852 | |
| 853 | DESCRIPTION |
| 854 | |
| 855 | Read in a copy of the first member in the inferior's dynamic |
| 856 | link map from the inferior's dynamic linker structures, and return |
| 857 | a pointer to the copy in our address space. |
| 858 | */ |
| 859 | |
| 860 | static struct link_map * |
| 861 | first_link_map_member () |
| 862 | { |
| 863 | struct link_map *lm = NULL; |
| 864 | |
| 865 | #ifndef SVR4_SHARED_LIBS |
| 866 | |
| 867 | read_memory (debug_base, (char *) &dynamic_copy, sizeof (dynamic_copy)); |
| 868 | if (dynamic_copy.ld_version >= 2) |
| 869 | { |
| 870 | /* It is a version that we can deal with, so read in the secondary |
| 871 | structure and find the address of the link map list from it. */ |
| 872 | read_memory ((CORE_ADDR) dynamic_copy.ld_un.ld_2, (char *) &ld_2_copy, |
| 873 | sizeof (struct link_dynamic_2)); |
| 874 | lm = ld_2_copy.ld_loaded; |
| 875 | } |
| 876 | |
| 877 | #else /* SVR4_SHARED_LIBS */ |
| 878 | |
| 879 | read_memory (debug_base, (char *) &debug_copy, sizeof (struct r_debug)); |
| 880 | /* FIXME: Perhaps we should validate the info somehow, perhaps by |
| 881 | checking r_version for a known version number, or r_state for |
| 882 | RT_CONSISTENT. */ |
| 883 | lm = debug_copy.r_map; |
| 884 | |
| 885 | #endif /* !SVR4_SHARED_LIBS */ |
| 886 | |
| 887 | return (lm); |
| 888 | } |
| 889 | |
| 890 | #ifdef SVR4_SHARED_LIBS |
| 891 | /* |
| 892 | |
| 893 | LOCAL FUNCTION |
| 894 | |
| 895 | open_exec_file_object |
| 896 | |
| 897 | SYNOPSIS |
| 898 | |
| 899 | void open_symbol_file_object (int from_tty) |
| 900 | |
| 901 | DESCRIPTION |
| 902 | |
| 903 | If no open symbol file, attempt to locate and open the main symbol |
| 904 | file. On SVR4 systems, this is the first link map entry. If its |
| 905 | name is here, we can open it. Useful when attaching to a process |
| 906 | without first loading its symbol file. |
| 907 | |
| 908 | */ |
| 909 | |
| 910 | int |
| 911 | open_symbol_file_object (arg) |
| 912 | PTR arg; |
| 913 | { |
| 914 | int from_tty = (int) arg; /* sneak past catch_errors */ |
| 915 | struct link_map *lm, lmcopy; |
| 916 | char *filename; |
| 917 | int errcode; |
| 918 | |
| 919 | if (symfile_objfile) |
| 920 | if (!query ("Attempt to reload symbols from process? ")) |
| 921 | return 0; |
| 922 | |
| 923 | if ((debug_base = locate_base ()) == 0) |
| 924 | return 0; /* failed somehow... */ |
| 925 | |
| 926 | /* First link map member should be the executable. */ |
| 927 | if ((lm = first_link_map_member ()) == NULL) |
| 928 | return 0; /* failed somehow... */ |
| 929 | |
| 930 | /* Read from target memory to GDB. */ |
| 931 | read_memory ((CORE_ADDR) lm, (void *) &lmcopy, sizeof (lmcopy)); |
| 932 | |
| 933 | if (lmcopy.l_name == 0) |
| 934 | return 0; /* no filename. */ |
| 935 | |
| 936 | /* Now fetch the filename from target memory. */ |
| 937 | target_read_string ((CORE_ADDR) lmcopy.l_name, &filename, |
| 938 | MAX_PATH_SIZE - 1, &errcode); |
| 939 | if (errcode) |
| 940 | { |
| 941 | warning ("failed to read exec filename from attached file: %s", |
| 942 | safe_strerror (errcode)); |
| 943 | return 0; |
| 944 | } |
| 945 | |
| 946 | make_cleanup ((make_cleanup_func) free, (void *) filename); |
| 947 | /* Have a pathname: read the symbol file. */ |
| 948 | symbol_file_command (filename, from_tty); |
| 949 | |
| 950 | return 1; |
| 951 | } |
| 952 | #endif /* SVR4_SHARED_LIBS */ |
| 953 | |
| 954 | /* |
| 955 | |
| 956 | LOCAL FUNCTION |
| 957 | |
| 958 | find_solib -- step through list of shared objects |
| 959 | |
| 960 | SYNOPSIS |
| 961 | |
| 962 | struct so_list *find_solib (struct so_list *so_list_ptr) |
| 963 | |
| 964 | DESCRIPTION |
| 965 | |
| 966 | This module contains the routine which finds the names of any |
| 967 | loaded "images" in the current process. The argument in must be |
| 968 | NULL on the first call, and then the returned value must be passed |
| 969 | in on subsequent calls. This provides the capability to "step" down |
| 970 | the list of loaded objects. On the last object, a NULL value is |
| 971 | returned. |
| 972 | |
| 973 | The arg and return value are "struct link_map" pointers, as defined |
| 974 | in <link.h>. |
| 975 | */ |
| 976 | |
| 977 | static struct so_list * |
| 978 | find_solib (so_list_ptr) |
| 979 | struct so_list *so_list_ptr; /* Last lm or NULL for first one */ |
| 980 | { |
| 981 | struct so_list *so_list_next = NULL; |
| 982 | struct link_map *lm = NULL; |
| 983 | struct so_list *new; |
| 984 | |
| 985 | if (so_list_ptr == NULL) |
| 986 | { |
| 987 | /* We are setting up for a new scan through the loaded images. */ |
| 988 | if ((so_list_next = so_list_head) == NULL) |
| 989 | { |
| 990 | /* We have not already read in the dynamic linking structures |
| 991 | from the inferior, lookup the address of the base structure. */ |
| 992 | debug_base = locate_base (); |
| 993 | if (debug_base != 0) |
| 994 | { |
| 995 | /* Read the base structure in and find the address of the first |
| 996 | link map list member. */ |
| 997 | lm = first_link_map_member (); |
| 998 | } |
| 999 | } |
| 1000 | } |
| 1001 | else |
| 1002 | { |
| 1003 | /* We have been called before, and are in the process of walking |
| 1004 | the shared library list. Advance to the next shared object. */ |
| 1005 | if ((lm = LM_NEXT (so_list_ptr)) == NULL) |
| 1006 | { |
| 1007 | /* We have hit the end of the list, so check to see if any were |
| 1008 | added, but be quiet if we can't read from the target any more. */ |
| 1009 | int status = target_read_memory ((CORE_ADDR) so_list_ptr->lmaddr, |
| 1010 | (char *) &(so_list_ptr->lm), |
| 1011 | sizeof (struct link_map)); |
| 1012 | if (status == 0) |
| 1013 | { |
| 1014 | lm = LM_NEXT (so_list_ptr); |
| 1015 | } |
| 1016 | else |
| 1017 | { |
| 1018 | lm = NULL; |
| 1019 | } |
| 1020 | } |
| 1021 | so_list_next = so_list_ptr->next; |
| 1022 | } |
| 1023 | if ((so_list_next == NULL) && (lm != NULL)) |
| 1024 | { |
| 1025 | /* Get next link map structure from inferior image and build a local |
| 1026 | abbreviated load_map structure */ |
| 1027 | new = (struct so_list *) xmalloc (sizeof (struct so_list)); |
| 1028 | memset ((char *) new, 0, sizeof (struct so_list)); |
| 1029 | new->lmaddr = lm; |
| 1030 | /* Add the new node as the next node in the list, or as the root |
| 1031 | node if this is the first one. */ |
| 1032 | if (so_list_ptr != NULL) |
| 1033 | { |
| 1034 | so_list_ptr->next = new; |
| 1035 | } |
| 1036 | else |
| 1037 | { |
| 1038 | so_list_head = new; |
| 1039 | |
| 1040 | if (!solib_cleanup_queued) |
| 1041 | { |
| 1042 | make_run_cleanup (do_clear_solib, NULL); |
| 1043 | solib_cleanup_queued = 1; |
| 1044 | } |
| 1045 | |
| 1046 | } |
| 1047 | so_list_next = new; |
| 1048 | read_memory ((CORE_ADDR) lm, (char *) &(new->lm), |
| 1049 | sizeof (struct link_map)); |
| 1050 | /* For SVR4 versions, the first entry in the link map is for the |
| 1051 | inferior executable, so we must ignore it. For some versions of |
| 1052 | SVR4, it has no name. For others (Solaris 2.3 for example), it |
| 1053 | does have a name, so we can no longer use a missing name to |
| 1054 | decide when to ignore it. */ |
| 1055 | if (!IGNORE_FIRST_LINK_MAP_ENTRY (new->lm)) |
| 1056 | { |
| 1057 | int errcode; |
| 1058 | char *buffer; |
| 1059 | target_read_string ((CORE_ADDR) LM_NAME (new), &buffer, |
| 1060 | MAX_PATH_SIZE - 1, &errcode); |
| 1061 | if (errcode != 0) |
| 1062 | { |
| 1063 | warning ("find_solib: Can't read pathname for load map: %s\n", |
| 1064 | safe_strerror (errcode)); |
| 1065 | return (so_list_next); |
| 1066 | } |
| 1067 | strncpy (new->so_name, buffer, MAX_PATH_SIZE - 1); |
| 1068 | new->so_name[MAX_PATH_SIZE - 1] = '\0'; |
| 1069 | free (buffer); |
| 1070 | catch_errors (solib_map_sections, new, |
| 1071 | "Error while mapping shared library sections:\n", |
| 1072 | RETURN_MASK_ALL); |
| 1073 | } |
| 1074 | } |
| 1075 | return (so_list_next); |
| 1076 | } |
| 1077 | |
| 1078 | /* A small stub to get us past the arg-passing pinhole of catch_errors. */ |
| 1079 | |
| 1080 | static int |
| 1081 | symbol_add_stub (arg) |
| 1082 | PTR arg; |
| 1083 | { |
| 1084 | register struct so_list *so = (struct so_list *) arg; /* catch_errs bogon */ |
| 1085 | CORE_ADDR text_addr = 0; |
| 1086 | |
| 1087 | if (so->textsection) |
| 1088 | text_addr = so->textsection->addr; |
| 1089 | else if (so->abfd != NULL) |
| 1090 | { |
| 1091 | asection *lowest_sect; |
| 1092 | |
| 1093 | /* If we didn't find a mapped non zero sized .text section, set up |
| 1094 | text_addr so that the relocation in symbol_file_add does no harm. */ |
| 1095 | |
| 1096 | lowest_sect = bfd_get_section_by_name (so->abfd, ".text"); |
| 1097 | if (lowest_sect == NULL) |
| 1098 | bfd_map_over_sections (so->abfd, find_lowest_section, |
| 1099 | (PTR) &lowest_sect); |
| 1100 | if (lowest_sect) |
| 1101 | text_addr = bfd_section_vma (so->abfd, lowest_sect) |
| 1102 | + (CORE_ADDR) LM_ADDR (so); |
| 1103 | } |
| 1104 | |
| 1105 | ALL_OBJFILES (so->objfile) |
| 1106 | { |
| 1107 | if (strcmp (so->objfile->name, so->so_name) == 0) |
| 1108 | return 1; |
| 1109 | } |
| 1110 | so->objfile = |
| 1111 | symbol_file_add (so->so_name, so->from_tty, |
| 1112 | text_addr, |
| 1113 | 0, 0, 0, 0, 1); |
| 1114 | return (1); |
| 1115 | } |
| 1116 | |
| 1117 | /* This function will check the so name to see if matches the main list. |
| 1118 | In some system the main object is in the list, which we want to exclude */ |
| 1119 | |
| 1120 | static int |
| 1121 | match_main (soname) |
| 1122 | char *soname; |
| 1123 | { |
| 1124 | char **mainp; |
| 1125 | |
| 1126 | for (mainp = main_name_list; *mainp != NULL; mainp++) |
| 1127 | { |
| 1128 | if (strcmp (soname, *mainp) == 0) |
| 1129 | return (1); |
| 1130 | } |
| 1131 | |
| 1132 | return (0); |
| 1133 | } |
| 1134 | |
| 1135 | /* |
| 1136 | |
| 1137 | GLOBAL FUNCTION |
| 1138 | |
| 1139 | solib_add -- add a shared library file to the symtab and section list |
| 1140 | |
| 1141 | SYNOPSIS |
| 1142 | |
| 1143 | void solib_add (char *arg_string, int from_tty, |
| 1144 | struct target_ops *target) |
| 1145 | |
| 1146 | DESCRIPTION |
| 1147 | |
| 1148 | */ |
| 1149 | |
| 1150 | void |
| 1151 | solib_add (arg_string, from_tty, target) |
| 1152 | char *arg_string; |
| 1153 | int from_tty; |
| 1154 | struct target_ops *target; |
| 1155 | { |
| 1156 | register struct so_list *so = NULL; /* link map state variable */ |
| 1157 | |
| 1158 | /* Last shared library that we read. */ |
| 1159 | struct so_list *so_last = NULL; |
| 1160 | |
| 1161 | char *re_err; |
| 1162 | int count; |
| 1163 | int old; |
| 1164 | |
| 1165 | #ifdef SVR4_SHARED_LIBS |
| 1166 | /* If we are attaching to a running process for which we |
| 1167 | have not opened a symbol file, we may be able to get its |
| 1168 | symbols now! */ |
| 1169 | if (attach_flag && |
| 1170 | symfile_objfile == NULL) |
| 1171 | catch_errors (open_symbol_file_object, (PTR) from_tty, |
| 1172 | "Error reading attached process's symbol file.\n", |
| 1173 | RETURN_MASK_ALL); |
| 1174 | |
| 1175 | #endif SVR4_SHARED_LIBS |
| 1176 | |
| 1177 | if ((re_err = re_comp (arg_string? arg_string : ".")) != NULL) |
| 1178 | { |
| 1179 | error ("Invalid regexp: %s", re_err); |
| 1180 | } |
| 1181 | |
| 1182 | /* Add the shared library sections to the section table of the |
| 1183 | specified target, if any. */ |
| 1184 | if (target) |
| 1185 | { |
| 1186 | /* Count how many new section_table entries there are. */ |
| 1187 | so = NULL; |
| 1188 | count = 0; |
| 1189 | while ((so = find_solib (so)) != NULL) |
| 1190 | { |
| 1191 | if (so->so_name[0] && !match_main (so->so_name)) |
| 1192 | { |
| 1193 | count += so->sections_end - so->sections; |
| 1194 | } |
| 1195 | } |
| 1196 | |
| 1197 | if (count) |
| 1198 | { |
| 1199 | |
| 1200 | /* Add these section table entries to the target's table. */ |
| 1201 | old = target_resize_to_sections (target, count); |
| 1202 | while ((so = find_solib (so)) != NULL) |
| 1203 | { |
| 1204 | if (so->so_name[0]) |
| 1205 | { |
| 1206 | count = so->sections_end - so->sections; |
| 1207 | memcpy ((char *) (target->to_sections + old), |
| 1208 | so->sections, |
| 1209 | (sizeof (struct section_table)) * count); |
| 1210 | old += count; |
| 1211 | } |
| 1212 | } |
| 1213 | } |
| 1214 | } |
| 1215 | |
| 1216 | /* Now add the symbol files. */ |
| 1217 | while ((so = find_solib (so)) != NULL) |
| 1218 | { |
| 1219 | if (so->so_name[0] && re_exec (so->so_name) && |
| 1220 | !match_main (so->so_name)) |
| 1221 | { |
| 1222 | so->from_tty = from_tty; |
| 1223 | if (so->symbols_loaded) |
| 1224 | { |
| 1225 | if (from_tty) |
| 1226 | { |
| 1227 | printf_unfiltered ("Symbols already loaded for %s\n", so->so_name); |
| 1228 | } |
| 1229 | } |
| 1230 | else if (catch_errors |
| 1231 | (symbol_add_stub, so, |
| 1232 | "Error while reading shared library symbols:\n", |
| 1233 | RETURN_MASK_ALL)) |
| 1234 | { |
| 1235 | so_last = so; |
| 1236 | so->symbols_loaded = 1; |
| 1237 | } |
| 1238 | } |
| 1239 | } |
| 1240 | |
| 1241 | /* Getting new symbols may change our opinion about what is |
| 1242 | frameless. */ |
| 1243 | if (so_last) |
| 1244 | reinit_frame_cache (); |
| 1245 | |
| 1246 | if (so_last) |
| 1247 | special_symbol_handling (so_last); |
| 1248 | } |
| 1249 | |
| 1250 | /* |
| 1251 | |
| 1252 | LOCAL FUNCTION |
| 1253 | |
| 1254 | info_sharedlibrary_command -- code for "info sharedlibrary" |
| 1255 | |
| 1256 | SYNOPSIS |
| 1257 | |
| 1258 | static void info_sharedlibrary_command () |
| 1259 | |
| 1260 | DESCRIPTION |
| 1261 | |
| 1262 | Walk through the shared library list and print information |
| 1263 | about each attached library. |
| 1264 | */ |
| 1265 | |
| 1266 | static void |
| 1267 | info_sharedlibrary_command (ignore, from_tty) |
| 1268 | char *ignore; |
| 1269 | int from_tty; |
| 1270 | { |
| 1271 | register struct so_list *so = NULL; /* link map state variable */ |
| 1272 | int header_done = 0; |
| 1273 | int addr_width; |
| 1274 | char *addr_fmt; |
| 1275 | |
| 1276 | if (exec_bfd == NULL) |
| 1277 | { |
| 1278 | printf_unfiltered ("No exec file.\n"); |
| 1279 | return; |
| 1280 | } |
| 1281 | |
| 1282 | #ifndef TARGET_ELF64 |
| 1283 | addr_width = 8 + 4; |
| 1284 | addr_fmt = "08l"; |
| 1285 | #else |
| 1286 | addr_width = 16 + 4; |
| 1287 | addr_fmt = "016l"; |
| 1288 | #endif |
| 1289 | |
| 1290 | while ((so = find_solib (so)) != NULL) |
| 1291 | { |
| 1292 | if (so->so_name[0]) |
| 1293 | { |
| 1294 | if (!header_done) |
| 1295 | { |
| 1296 | printf_unfiltered ("%-*s%-*s%-12s%s\n", addr_width, "From", |
| 1297 | addr_width, "To", "Syms Read", |
| 1298 | "Shared Object Library"); |
| 1299 | header_done++; |
| 1300 | } |
| 1301 | |
| 1302 | printf_unfiltered ("%-*s", addr_width, |
| 1303 | local_hex_string_custom ((unsigned long) LM_ADDR (so), |
| 1304 | addr_fmt)); |
| 1305 | printf_unfiltered ("%-*s", addr_width, |
| 1306 | local_hex_string_custom ((unsigned long) so->lmend, |
| 1307 | addr_fmt)); |
| 1308 | printf_unfiltered ("%-12s", so->symbols_loaded ? "Yes" : "No"); |
| 1309 | printf_unfiltered ("%s\n", so->so_name); |
| 1310 | } |
| 1311 | } |
| 1312 | if (so_list_head == NULL) |
| 1313 | { |
| 1314 | printf_unfiltered ("No shared libraries loaded at this time.\n"); |
| 1315 | } |
| 1316 | } |
| 1317 | |
| 1318 | /* |
| 1319 | |
| 1320 | GLOBAL FUNCTION |
| 1321 | |
| 1322 | solib_address -- check to see if an address is in a shared lib |
| 1323 | |
| 1324 | SYNOPSIS |
| 1325 | |
| 1326 | char * solib_address (CORE_ADDR address) |
| 1327 | |
| 1328 | DESCRIPTION |
| 1329 | |
| 1330 | Provides a hook for other gdb routines to discover whether or |
| 1331 | not a particular address is within the mapped address space of |
| 1332 | a shared library. Any address between the base mapping address |
| 1333 | and the first address beyond the end of the last mapping, is |
| 1334 | considered to be within the shared library address space, for |
| 1335 | our purposes. |
| 1336 | |
| 1337 | For example, this routine is called at one point to disable |
| 1338 | breakpoints which are in shared libraries that are not currently |
| 1339 | mapped in. |
| 1340 | */ |
| 1341 | |
| 1342 | char * |
| 1343 | solib_address (address) |
| 1344 | CORE_ADDR address; |
| 1345 | { |
| 1346 | register struct so_list *so = 0; /* link map state variable */ |
| 1347 | |
| 1348 | while ((so = find_solib (so)) != NULL) |
| 1349 | { |
| 1350 | if (so->so_name[0]) |
| 1351 | { |
| 1352 | if ((address >= (CORE_ADDR) LM_ADDR (so)) && |
| 1353 | (address < (CORE_ADDR) so->lmend)) |
| 1354 | return (so->so_name); |
| 1355 | } |
| 1356 | } |
| 1357 | return (0); |
| 1358 | } |
| 1359 | |
| 1360 | /* Called by free_all_symtabs */ |
| 1361 | |
| 1362 | void |
| 1363 | clear_solib () |
| 1364 | { |
| 1365 | struct so_list *next; |
| 1366 | char *bfd_filename; |
| 1367 | |
| 1368 | /* This function is expected to handle ELF shared libraries. It is |
| 1369 | also used on Solaris, which can run either ELF or a.out binaries |
| 1370 | (for compatibility with SunOS 4), both of which can use shared |
| 1371 | libraries. So we don't know whether we have an ELF executable or |
| 1372 | an a.out executable until the user chooses an executable file. |
| 1373 | |
| 1374 | ELF shared libraries don't get mapped into the address space |
| 1375 | until after the program starts, so we'd better not try to insert |
| 1376 | breakpoints in them immediately. We have to wait until the |
| 1377 | dynamic linker has loaded them; we'll hit a bp_shlib_event |
| 1378 | breakpoint (look for calls to create_solib_event_breakpoint) when |
| 1379 | it's ready. |
| 1380 | |
| 1381 | SunOS shared libraries seem to be different --- they're present |
| 1382 | as soon as the process begins execution, so there's no need to |
| 1383 | put off inserting breakpoints. There's also nowhere to put a |
| 1384 | bp_shlib_event breakpoint, so if we put it off, we'll never get |
| 1385 | around to it. |
| 1386 | |
| 1387 | So: disable breakpoints only if we're using ELF shared libs. */ |
| 1388 | if (exec_bfd != NULL |
| 1389 | && bfd_get_flavour (exec_bfd) != bfd_target_aout_flavour) |
| 1390 | disable_breakpoints_in_shlibs (1); |
| 1391 | |
| 1392 | while (so_list_head) |
| 1393 | { |
| 1394 | if (so_list_head->sections) |
| 1395 | { |
| 1396 | free ((PTR) so_list_head->sections); |
| 1397 | } |
| 1398 | if (so_list_head->abfd) |
| 1399 | { |
| 1400 | bfd_filename = bfd_get_filename (so_list_head->abfd); |
| 1401 | if (!bfd_close (so_list_head->abfd)) |
| 1402 | warning ("cannot close \"%s\": %s", |
| 1403 | bfd_filename, bfd_errmsg (bfd_get_error ())); |
| 1404 | } |
| 1405 | else |
| 1406 | /* This happens for the executable on SVR4. */ |
| 1407 | bfd_filename = NULL; |
| 1408 | |
| 1409 | next = so_list_head->next; |
| 1410 | if (bfd_filename) |
| 1411 | free ((PTR) bfd_filename); |
| 1412 | free ((PTR) so_list_head); |
| 1413 | so_list_head = next; |
| 1414 | } |
| 1415 | debug_base = 0; |
| 1416 | } |
| 1417 | |
| 1418 | static void |
| 1419 | do_clear_solib (dummy) |
| 1420 | PTR dummy; |
| 1421 | { |
| 1422 | solib_cleanup_queued = 0; |
| 1423 | clear_solib (); |
| 1424 | } |
| 1425 | |
| 1426 | #ifdef SVR4_SHARED_LIBS |
| 1427 | |
| 1428 | /* Return 1 if PC lies in the dynamic symbol resolution code of the |
| 1429 | SVR4 run time loader. */ |
| 1430 | |
| 1431 | static CORE_ADDR interp_text_sect_low; |
| 1432 | static CORE_ADDR interp_text_sect_high; |
| 1433 | static CORE_ADDR interp_plt_sect_low; |
| 1434 | static CORE_ADDR interp_plt_sect_high; |
| 1435 | |
| 1436 | int |
| 1437 | in_svr4_dynsym_resolve_code (pc) |
| 1438 | CORE_ADDR pc; |
| 1439 | { |
| 1440 | return ((pc >= interp_text_sect_low && pc < interp_text_sect_high) |
| 1441 | || (pc >= interp_plt_sect_low && pc < interp_plt_sect_high) |
| 1442 | || in_plt_section (pc, NULL)); |
| 1443 | } |
| 1444 | #endif |
| 1445 | |
| 1446 | /* |
| 1447 | |
| 1448 | LOCAL FUNCTION |
| 1449 | |
| 1450 | disable_break -- remove the "mapping changed" breakpoint |
| 1451 | |
| 1452 | SYNOPSIS |
| 1453 | |
| 1454 | static int disable_break () |
| 1455 | |
| 1456 | DESCRIPTION |
| 1457 | |
| 1458 | Removes the breakpoint that gets hit when the dynamic linker |
| 1459 | completes a mapping change. |
| 1460 | |
| 1461 | */ |
| 1462 | |
| 1463 | #ifndef SVR4_SHARED_LIBS |
| 1464 | |
| 1465 | static int |
| 1466 | disable_break () |
| 1467 | { |
| 1468 | int status = 1; |
| 1469 | |
| 1470 | #ifndef SVR4_SHARED_LIBS |
| 1471 | |
| 1472 | int in_debugger = 0; |
| 1473 | |
| 1474 | /* Read the debugger structure from the inferior to retrieve the |
| 1475 | address of the breakpoint and the original contents of the |
| 1476 | breakpoint address. Remove the breakpoint by writing the original |
| 1477 | contents back. */ |
| 1478 | |
| 1479 | read_memory (debug_addr, (char *) &debug_copy, sizeof (debug_copy)); |
| 1480 | |
| 1481 | /* Set `in_debugger' to zero now. */ |
| 1482 | |
| 1483 | write_memory (flag_addr, (char *) &in_debugger, sizeof (in_debugger)); |
| 1484 | |
| 1485 | breakpoint_addr = (CORE_ADDR) debug_copy.ldd_bp_addr; |
| 1486 | write_memory (breakpoint_addr, (char *) &debug_copy.ldd_bp_inst, |
| 1487 | sizeof (debug_copy.ldd_bp_inst)); |
| 1488 | |
| 1489 | #else /* SVR4_SHARED_LIBS */ |
| 1490 | |
| 1491 | /* Note that breakpoint address and original contents are in our address |
| 1492 | space, so we just need to write the original contents back. */ |
| 1493 | |
| 1494 | if (memory_remove_breakpoint (breakpoint_addr, shadow_contents) != 0) |
| 1495 | { |
| 1496 | status = 0; |
| 1497 | } |
| 1498 | |
| 1499 | #endif /* !SVR4_SHARED_LIBS */ |
| 1500 | |
| 1501 | /* For the SVR4 version, we always know the breakpoint address. For the |
| 1502 | SunOS version we don't know it until the above code is executed. |
| 1503 | Grumble if we are stopped anywhere besides the breakpoint address. */ |
| 1504 | |
| 1505 | if (stop_pc != breakpoint_addr) |
| 1506 | { |
| 1507 | warning ("stopped at unknown breakpoint while handling shared libraries"); |
| 1508 | } |
| 1509 | |
| 1510 | return (status); |
| 1511 | } |
| 1512 | |
| 1513 | #endif /* #ifdef SVR4_SHARED_LIBS */ |
| 1514 | |
| 1515 | /* |
| 1516 | |
| 1517 | LOCAL FUNCTION |
| 1518 | |
| 1519 | enable_break -- arrange for dynamic linker to hit breakpoint |
| 1520 | |
| 1521 | SYNOPSIS |
| 1522 | |
| 1523 | int enable_break (void) |
| 1524 | |
| 1525 | DESCRIPTION |
| 1526 | |
| 1527 | Both the SunOS and the SVR4 dynamic linkers have, as part of their |
| 1528 | debugger interface, support for arranging for the inferior to hit |
| 1529 | a breakpoint after mapping in the shared libraries. This function |
| 1530 | enables that breakpoint. |
| 1531 | |
| 1532 | For SunOS, there is a special flag location (in_debugger) which we |
| 1533 | set to 1. When the dynamic linker sees this flag set, it will set |
| 1534 | a breakpoint at a location known only to itself, after saving the |
| 1535 | original contents of that place and the breakpoint address itself, |
| 1536 | in it's own internal structures. When we resume the inferior, it |
| 1537 | will eventually take a SIGTRAP when it runs into the breakpoint. |
| 1538 | We handle this (in a different place) by restoring the contents of |
| 1539 | the breakpointed location (which is only known after it stops), |
| 1540 | chasing around to locate the shared libraries that have been |
| 1541 | loaded, then resuming. |
| 1542 | |
| 1543 | For SVR4, the debugger interface structure contains a member (r_brk) |
| 1544 | which is statically initialized at the time the shared library is |
| 1545 | built, to the offset of a function (_r_debug_state) which is guaran- |
| 1546 | teed to be called once before mapping in a library, and again when |
| 1547 | the mapping is complete. At the time we are examining this member, |
| 1548 | it contains only the unrelocated offset of the function, so we have |
| 1549 | to do our own relocation. Later, when the dynamic linker actually |
| 1550 | runs, it relocates r_brk to be the actual address of _r_debug_state(). |
| 1551 | |
| 1552 | The debugger interface structure also contains an enumeration which |
| 1553 | is set to either RT_ADD or RT_DELETE prior to changing the mapping, |
| 1554 | depending upon whether or not the library is being mapped or unmapped, |
| 1555 | and then set to RT_CONSISTENT after the library is mapped/unmapped. |
| 1556 | */ |
| 1557 | |
| 1558 | static int |
| 1559 | enable_break () |
| 1560 | { |
| 1561 | int success = 0; |
| 1562 | |
| 1563 | #ifndef SVR4_SHARED_LIBS |
| 1564 | |
| 1565 | int j; |
| 1566 | int in_debugger; |
| 1567 | |
| 1568 | /* Get link_dynamic structure */ |
| 1569 | |
| 1570 | j = target_read_memory (debug_base, (char *) &dynamic_copy, |
| 1571 | sizeof (dynamic_copy)); |
| 1572 | if (j) |
| 1573 | { |
| 1574 | /* unreadable */ |
| 1575 | return (0); |
| 1576 | } |
| 1577 | |
| 1578 | /* Calc address of debugger interface structure */ |
| 1579 | |
| 1580 | debug_addr = (CORE_ADDR) dynamic_copy.ldd; |
| 1581 | |
| 1582 | /* Calc address of `in_debugger' member of debugger interface structure */ |
| 1583 | |
| 1584 | flag_addr = debug_addr + (CORE_ADDR) ((char *) &debug_copy.ldd_in_debugger - |
| 1585 | (char *) &debug_copy); |
| 1586 | |
| 1587 | /* Write a value of 1 to this member. */ |
| 1588 | |
| 1589 | in_debugger = 1; |
| 1590 | write_memory (flag_addr, (char *) &in_debugger, sizeof (in_debugger)); |
| 1591 | success = 1; |
| 1592 | |
| 1593 | #else /* SVR4_SHARED_LIBS */ |
| 1594 | |
| 1595 | #ifdef BKPT_AT_SYMBOL |
| 1596 | |
| 1597 | struct minimal_symbol *msymbol; |
| 1598 | char **bkpt_namep; |
| 1599 | asection *interp_sect; |
| 1600 | |
| 1601 | /* First, remove all the solib event breakpoints. Their addresses |
| 1602 | may have changed since the last time we ran the program. */ |
| 1603 | remove_solib_event_breakpoints (); |
| 1604 | |
| 1605 | #ifdef SVR4_SHARED_LIBS |
| 1606 | interp_text_sect_low = interp_text_sect_high = 0; |
| 1607 | interp_plt_sect_low = interp_plt_sect_high = 0; |
| 1608 | |
| 1609 | /* Find the .interp section; if not found, warn the user and drop |
| 1610 | into the old breakpoint at symbol code. */ |
| 1611 | interp_sect = bfd_get_section_by_name (exec_bfd, ".interp"); |
| 1612 | if (interp_sect) |
| 1613 | { |
| 1614 | unsigned int interp_sect_size; |
| 1615 | char *buf; |
| 1616 | CORE_ADDR load_addr; |
| 1617 | bfd *tmp_bfd; |
| 1618 | CORE_ADDR sym_addr = 0; |
| 1619 | |
| 1620 | /* Read the contents of the .interp section into a local buffer; |
| 1621 | the contents specify the dynamic linker this program uses. */ |
| 1622 | interp_sect_size = bfd_section_size (exec_bfd, interp_sect); |
| 1623 | buf = alloca (interp_sect_size); |
| 1624 | bfd_get_section_contents (exec_bfd, interp_sect, |
| 1625 | buf, 0, interp_sect_size); |
| 1626 | |
| 1627 | /* Now we need to figure out where the dynamic linker was |
| 1628 | loaded so that we can load its symbols and place a breakpoint |
| 1629 | in the dynamic linker itself. |
| 1630 | |
| 1631 | This address is stored on the stack. However, I've been unable |
| 1632 | to find any magic formula to find it for Solaris (appears to |
| 1633 | be trivial on GNU/Linux). Therefore, we have to try an alternate |
| 1634 | mechanism to find the dynamic linker's base address. */ |
| 1635 | tmp_bfd = bfd_openr (buf, gnutarget); |
| 1636 | if (tmp_bfd == NULL) |
| 1637 | goto bkpt_at_symbol; |
| 1638 | |
| 1639 | /* Make sure the dynamic linker's really a useful object. */ |
| 1640 | if (!bfd_check_format (tmp_bfd, bfd_object)) |
| 1641 | { |
| 1642 | warning ("Unable to grok dynamic linker %s as an object file", buf); |
| 1643 | bfd_close (tmp_bfd); |
| 1644 | goto bkpt_at_symbol; |
| 1645 | } |
| 1646 | |
| 1647 | /* We find the dynamic linker's base address by examining the |
| 1648 | current pc (which point at the entry point for the dynamic |
| 1649 | linker) and subtracting the offset of the entry point. */ |
| 1650 | load_addr = read_pc () - tmp_bfd->start_address; |
| 1651 | |
| 1652 | /* Record the relocated start and end address of the dynamic linker |
| 1653 | text and plt section for in_svr4_dynsym_resolve_code. */ |
| 1654 | interp_sect = bfd_get_section_by_name (tmp_bfd, ".text"); |
| 1655 | if (interp_sect) |
| 1656 | { |
| 1657 | interp_text_sect_low = |
| 1658 | bfd_section_vma (tmp_bfd, interp_sect) + load_addr; |
| 1659 | interp_text_sect_high = |
| 1660 | interp_text_sect_low + bfd_section_size (tmp_bfd, interp_sect); |
| 1661 | } |
| 1662 | interp_sect = bfd_get_section_by_name (tmp_bfd, ".plt"); |
| 1663 | if (interp_sect) |
| 1664 | { |
| 1665 | interp_plt_sect_low = |
| 1666 | bfd_section_vma (tmp_bfd, interp_sect) + load_addr; |
| 1667 | interp_plt_sect_high = |
| 1668 | interp_plt_sect_low + bfd_section_size (tmp_bfd, interp_sect); |
| 1669 | } |
| 1670 | |
| 1671 | /* Now try to set a breakpoint in the dynamic linker. */ |
| 1672 | for (bkpt_namep = solib_break_names; *bkpt_namep != NULL; bkpt_namep++) |
| 1673 | { |
| 1674 | sym_addr = bfd_lookup_symbol (tmp_bfd, *bkpt_namep); |
| 1675 | if (sym_addr != 0) |
| 1676 | break; |
| 1677 | } |
| 1678 | |
| 1679 | /* We're done with the temporary bfd. */ |
| 1680 | bfd_close (tmp_bfd); |
| 1681 | |
| 1682 | if (sym_addr != 0) |
| 1683 | { |
| 1684 | create_solib_event_breakpoint (load_addr + sym_addr); |
| 1685 | return 1; |
| 1686 | } |
| 1687 | |
| 1688 | /* For whatever reason we couldn't set a breakpoint in the dynamic |
| 1689 | linker. Warn and drop into the old code. */ |
| 1690 | bkpt_at_symbol: |
| 1691 | warning ("Unable to find dynamic linker breakpoint function.\nGDB will be unable to debug shared library initializers\nand track explicitly loaded dynamic code."); |
| 1692 | } |
| 1693 | #endif |
| 1694 | |
| 1695 | /* Scan through the list of symbols, trying to look up the symbol and |
| 1696 | set a breakpoint there. Terminate loop when we/if we succeed. */ |
| 1697 | |
| 1698 | breakpoint_addr = 0; |
| 1699 | for (bkpt_namep = bkpt_names; *bkpt_namep != NULL; bkpt_namep++) |
| 1700 | { |
| 1701 | msymbol = lookup_minimal_symbol (*bkpt_namep, NULL, symfile_objfile); |
| 1702 | if ((msymbol != NULL) && (SYMBOL_VALUE_ADDRESS (msymbol) != 0)) |
| 1703 | { |
| 1704 | create_solib_event_breakpoint (SYMBOL_VALUE_ADDRESS (msymbol)); |
| 1705 | return 1; |
| 1706 | } |
| 1707 | } |
| 1708 | |
| 1709 | /* Nothing good happened. */ |
| 1710 | success = 0; |
| 1711 | |
| 1712 | #endif /* BKPT_AT_SYMBOL */ |
| 1713 | |
| 1714 | #endif /* !SVR4_SHARED_LIBS */ |
| 1715 | |
| 1716 | return (success); |
| 1717 | } |
| 1718 | |
| 1719 | /* |
| 1720 | |
| 1721 | GLOBAL FUNCTION |
| 1722 | |
| 1723 | solib_create_inferior_hook -- shared library startup support |
| 1724 | |
| 1725 | SYNOPSIS |
| 1726 | |
| 1727 | void solib_create_inferior_hook() |
| 1728 | |
| 1729 | DESCRIPTION |
| 1730 | |
| 1731 | When gdb starts up the inferior, it nurses it along (through the |
| 1732 | shell) until it is ready to execute it's first instruction. At this |
| 1733 | point, this function gets called via expansion of the macro |
| 1734 | SOLIB_CREATE_INFERIOR_HOOK. |
| 1735 | |
| 1736 | For SunOS executables, this first instruction is typically the |
| 1737 | one at "_start", or a similar text label, regardless of whether |
| 1738 | the executable is statically or dynamically linked. The runtime |
| 1739 | startup code takes care of dynamically linking in any shared |
| 1740 | libraries, once gdb allows the inferior to continue. |
| 1741 | |
| 1742 | For SVR4 executables, this first instruction is either the first |
| 1743 | instruction in the dynamic linker (for dynamically linked |
| 1744 | executables) or the instruction at "start" for statically linked |
| 1745 | executables. For dynamically linked executables, the system |
| 1746 | first exec's /lib/libc.so.N, which contains the dynamic linker, |
| 1747 | and starts it running. The dynamic linker maps in any needed |
| 1748 | shared libraries, maps in the actual user executable, and then |
| 1749 | jumps to "start" in the user executable. |
| 1750 | |
| 1751 | For both SunOS shared libraries, and SVR4 shared libraries, we |
| 1752 | can arrange to cooperate with the dynamic linker to discover the |
| 1753 | names of shared libraries that are dynamically linked, and the |
| 1754 | base addresses to which they are linked. |
| 1755 | |
| 1756 | This function is responsible for discovering those names and |
| 1757 | addresses, and saving sufficient information about them to allow |
| 1758 | their symbols to be read at a later time. |
| 1759 | |
| 1760 | FIXME |
| 1761 | |
| 1762 | Between enable_break() and disable_break(), this code does not |
| 1763 | properly handle hitting breakpoints which the user might have |
| 1764 | set in the startup code or in the dynamic linker itself. Proper |
| 1765 | handling will probably have to wait until the implementation is |
| 1766 | changed to use the "breakpoint handler function" method. |
| 1767 | |
| 1768 | Also, what if child has exit()ed? Must exit loop somehow. |
| 1769 | */ |
| 1770 | |
| 1771 | void |
| 1772 | solib_create_inferior_hook () |
| 1773 | { |
| 1774 | /* If we are using the BKPT_AT_SYMBOL code, then we don't need the base |
| 1775 | yet. In fact, in the case of a SunOS4 executable being run on |
| 1776 | Solaris, we can't get it yet. find_solib will get it when it needs |
| 1777 | it. */ |
| 1778 | #if !(defined (SVR4_SHARED_LIBS) && defined (BKPT_AT_SYMBOL)) |
| 1779 | if ((debug_base = locate_base ()) == 0) |
| 1780 | { |
| 1781 | /* Can't find the symbol or the executable is statically linked. */ |
| 1782 | return; |
| 1783 | } |
| 1784 | #endif |
| 1785 | |
| 1786 | if (!enable_break ()) |
| 1787 | { |
| 1788 | warning ("shared library handler failed to enable breakpoint"); |
| 1789 | return; |
| 1790 | } |
| 1791 | |
| 1792 | #if !defined(SVR4_SHARED_LIBS) || defined(_SCO_DS) |
| 1793 | /* SCO and SunOS need the loop below, other systems should be using the |
| 1794 | special shared library breakpoints and the shared library breakpoint |
| 1795 | service routine. |
| 1796 | |
| 1797 | Now run the target. It will eventually hit the breakpoint, at |
| 1798 | which point all of the libraries will have been mapped in and we |
| 1799 | can go groveling around in the dynamic linker structures to find |
| 1800 | out what we need to know about them. */ |
| 1801 | |
| 1802 | clear_proceed_status (); |
| 1803 | stop_soon_quietly = 1; |
| 1804 | stop_signal = TARGET_SIGNAL_0; |
| 1805 | do |
| 1806 | { |
| 1807 | target_resume (-1, 0, stop_signal); |
| 1808 | wait_for_inferior (); |
| 1809 | } |
| 1810 | while (stop_signal != TARGET_SIGNAL_TRAP); |
| 1811 | stop_soon_quietly = 0; |
| 1812 | |
| 1813 | #if !defined(_SCO_DS) |
| 1814 | /* We are now either at the "mapping complete" breakpoint (or somewhere |
| 1815 | else, a condition we aren't prepared to deal with anyway), so adjust |
| 1816 | the PC as necessary after a breakpoint, disable the breakpoint, and |
| 1817 | add any shared libraries that were mapped in. */ |
| 1818 | |
| 1819 | if (DECR_PC_AFTER_BREAK) |
| 1820 | { |
| 1821 | stop_pc -= DECR_PC_AFTER_BREAK; |
| 1822 | write_register (PC_REGNUM, stop_pc); |
| 1823 | } |
| 1824 | |
| 1825 | if (!disable_break ()) |
| 1826 | { |
| 1827 | warning ("shared library handler failed to disable breakpoint"); |
| 1828 | } |
| 1829 | |
| 1830 | if (auto_solib_add) |
| 1831 | solib_add ((char *) 0, 0, (struct target_ops *) 0); |
| 1832 | #endif /* ! _SCO_DS */ |
| 1833 | #endif |
| 1834 | } |
| 1835 | |
| 1836 | /* |
| 1837 | |
| 1838 | LOCAL FUNCTION |
| 1839 | |
| 1840 | special_symbol_handling -- additional shared library symbol handling |
| 1841 | |
| 1842 | SYNOPSIS |
| 1843 | |
| 1844 | void special_symbol_handling (struct so_list *so) |
| 1845 | |
| 1846 | DESCRIPTION |
| 1847 | |
| 1848 | Once the symbols from a shared object have been loaded in the usual |
| 1849 | way, we are called to do any system specific symbol handling that |
| 1850 | is needed. |
| 1851 | |
| 1852 | For SunOS4, this consists of grunging around in the dynamic |
| 1853 | linkers structures to find symbol definitions for "common" symbols |
| 1854 | and adding them to the minimal symbol table for the runtime common |
| 1855 | objfile. |
| 1856 | |
| 1857 | */ |
| 1858 | |
| 1859 | static void |
| 1860 | special_symbol_handling (so) |
| 1861 | struct so_list *so; |
| 1862 | { |
| 1863 | #ifndef SVR4_SHARED_LIBS |
| 1864 | int j; |
| 1865 | |
| 1866 | if (debug_addr == 0) |
| 1867 | { |
| 1868 | /* Get link_dynamic structure */ |
| 1869 | |
| 1870 | j = target_read_memory (debug_base, (char *) &dynamic_copy, |
| 1871 | sizeof (dynamic_copy)); |
| 1872 | if (j) |
| 1873 | { |
| 1874 | /* unreadable */ |
| 1875 | return; |
| 1876 | } |
| 1877 | |
| 1878 | /* Calc address of debugger interface structure */ |
| 1879 | /* FIXME, this needs work for cross-debugging of core files |
| 1880 | (byteorder, size, alignment, etc). */ |
| 1881 | |
| 1882 | debug_addr = (CORE_ADDR) dynamic_copy.ldd; |
| 1883 | } |
| 1884 | |
| 1885 | /* Read the debugger structure from the inferior, just to make sure |
| 1886 | we have a current copy. */ |
| 1887 | |
| 1888 | j = target_read_memory (debug_addr, (char *) &debug_copy, |
| 1889 | sizeof (debug_copy)); |
| 1890 | if (j) |
| 1891 | return; /* unreadable */ |
| 1892 | |
| 1893 | /* Get common symbol definitions for the loaded object. */ |
| 1894 | |
| 1895 | if (debug_copy.ldd_cp) |
| 1896 | { |
| 1897 | solib_add_common_symbols (debug_copy.ldd_cp); |
| 1898 | } |
| 1899 | |
| 1900 | #endif /* !SVR4_SHARED_LIBS */ |
| 1901 | } |
| 1902 | |
| 1903 | |
| 1904 | /* |
| 1905 | |
| 1906 | LOCAL FUNCTION |
| 1907 | |
| 1908 | sharedlibrary_command -- handle command to explicitly add library |
| 1909 | |
| 1910 | SYNOPSIS |
| 1911 | |
| 1912 | static void sharedlibrary_command (char *args, int from_tty) |
| 1913 | |
| 1914 | DESCRIPTION |
| 1915 | |
| 1916 | */ |
| 1917 | |
| 1918 | static void |
| 1919 | sharedlibrary_command (args, from_tty) |
| 1920 | char *args; |
| 1921 | int from_tty; |
| 1922 | { |
| 1923 | dont_repeat (); |
| 1924 | solib_add (args, from_tty, (struct target_ops *) 0); |
| 1925 | } |
| 1926 | |
| 1927 | #endif /* HAVE_LINK_H */ |
| 1928 | |
| 1929 | void |
| 1930 | _initialize_solib () |
| 1931 | { |
| 1932 | #ifdef HAVE_LINK_H |
| 1933 | |
| 1934 | add_com ("sharedlibrary", class_files, sharedlibrary_command, |
| 1935 | "Load shared object library symbols for files matching REGEXP."); |
| 1936 | add_info ("sharedlibrary", info_sharedlibrary_command, |
| 1937 | "Status of loaded shared object libraries."); |
| 1938 | |
| 1939 | add_show_from_set |
| 1940 | (add_set_cmd ("auto-solib-add", class_support, var_zinteger, |
| 1941 | (char *) &auto_solib_add, |
| 1942 | "Set autoloading of shared library symbols.\n\ |
| 1943 | If nonzero, symbols from all shared object libraries will be loaded\n\ |
| 1944 | automatically when the inferior begins execution or when the dynamic linker\n\ |
| 1945 | informs gdb that a new library has been loaded. Otherwise, symbols\n\ |
| 1946 | must be loaded manually, using `sharedlibrary'.", |
| 1947 | &setlist), |
| 1948 | &showlist); |
| 1949 | |
| 1950 | add_show_from_set |
| 1951 | (add_set_cmd ("solib-absolute-prefix", class_support, var_filename, |
| 1952 | (char *) &solib_absolute_prefix, |
| 1953 | "Set prefix for loading absolute shared library symbol files.\n\ |
| 1954 | For other (relative) files, you can add values using `set solib-search-path'.", |
| 1955 | &setlist), |
| 1956 | &showlist); |
| 1957 | add_show_from_set |
| 1958 | (add_set_cmd ("solib-search-path", class_support, var_string, |
| 1959 | (char *) &solib_search_path, |
| 1960 | "Set the search path for loading non-absolute shared library symbol files.\n\ |
| 1961 | This takes precedence over the environment variables PATH and LD_LIBRARY_PATH.", |
| 1962 | &setlist), |
| 1963 | &showlist); |
| 1964 | |
| 1965 | #endif /* HAVE_LINK_H */ |
| 1966 | } |