| 1 | /* GDB routines for manipulating objfiles. |
| 2 | Copyright 1992 Free Software Foundation, Inc. |
| 3 | Contributed by Cygnus Support, using pieces from other GDB modules. |
| 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., 675 Mass Ave, Cambridge, MA 02139, USA. */ |
| 20 | |
| 21 | /* This file contains support routines for creating, manipulating, and |
| 22 | destroying objfile structures. */ |
| 23 | |
| 24 | #include "defs.h" |
| 25 | #include "bfd.h" /* Binary File Description */ |
| 26 | #include "symtab.h" |
| 27 | #include "symfile.h" |
| 28 | #include "objfiles.h" |
| 29 | |
| 30 | #include <sys/types.h> |
| 31 | #include <sys/stat.h> |
| 32 | #include <fcntl.h> |
| 33 | #include <obstack.h> |
| 34 | |
| 35 | /* Prototypes for local functions */ |
| 36 | |
| 37 | #if !defined(NO_MMALLOC) && defined(HAVE_MMAP) |
| 38 | |
| 39 | static int |
| 40 | open_existing_mapped_file PARAMS ((char *, long, int)); |
| 41 | |
| 42 | static int |
| 43 | open_mapped_file PARAMS ((char *filename, long mtime, int mapped)); |
| 44 | |
| 45 | static CORE_ADDR |
| 46 | map_to_address PARAMS ((void)); |
| 47 | |
| 48 | #endif /* !defined(NO_MMALLOC) && defined(HAVE_MMAP) */ |
| 49 | |
| 50 | /* Message to be printed before the error message, when an error occurs. */ |
| 51 | |
| 52 | extern char *error_pre_print; |
| 53 | |
| 54 | /* Externally visible variables that are owned by this module. |
| 55 | See declarations in objfile.h for more info. */ |
| 56 | |
| 57 | struct objfile *object_files; /* Linked list of all objfiles */ |
| 58 | struct objfile *current_objfile; /* For symbol file being read in */ |
| 59 | struct objfile *symfile_objfile; /* Main symbol table loaded from */ |
| 60 | |
| 61 | int mapped_symbol_files; /* Try to use mapped symbol files */ |
| 62 | |
| 63 | /* Locate all mappable sections of a BFD file. |
| 64 | objfile_p_char is a char * to get it through |
| 65 | bfd_map_over_sections; we cast it back to its proper type. */ |
| 66 | |
| 67 | static void |
| 68 | add_to_objfile_sections (abfd, asect, objfile_p_char) |
| 69 | bfd *abfd; |
| 70 | sec_ptr asect; |
| 71 | PTR objfile_p_char; |
| 72 | { |
| 73 | struct objfile *objfile = (struct objfile *) objfile_p_char; |
| 74 | struct obj_section section; |
| 75 | flagword aflag; |
| 76 | |
| 77 | aflag = bfd_get_section_flags (abfd, asect); |
| 78 | /* FIXME, we need to handle BSS segment here...it alloc's but doesn't load */ |
| 79 | if (!(aflag & SEC_LOAD)) |
| 80 | return; |
| 81 | if (0 == bfd_section_size (abfd, asect)) |
| 82 | return; |
| 83 | section.offset = 0; |
| 84 | section.objfile = objfile; |
| 85 | section.sec_ptr = asect; |
| 86 | section.addr = bfd_section_vma (abfd, asect); |
| 87 | section.endaddr = section.addr + bfd_section_size (abfd, asect); |
| 88 | obstack_grow (&objfile->psymbol_obstack, §ion, sizeof(section)); |
| 89 | objfile->sections_end = (struct obj_section *) (((int) objfile->sections_end) + 1); |
| 90 | } |
| 91 | |
| 92 | /* Builds a section table for OBJFILE. |
| 93 | Returns 0 if OK, 1 on error. */ |
| 94 | |
| 95 | static int |
| 96 | build_objfile_section_table (objfile) |
| 97 | struct objfile *objfile; |
| 98 | { |
| 99 | if (objfile->sections) |
| 100 | abort(); |
| 101 | |
| 102 | objfile->sections_end = 0; |
| 103 | bfd_map_over_sections (objfile->obfd, add_to_objfile_sections, (char *)objfile); |
| 104 | objfile->sections = (struct obj_section *) |
| 105 | obstack_finish (&objfile->psymbol_obstack); |
| 106 | objfile->sections_end = objfile->sections + (int) objfile->sections_end; |
| 107 | return(0); |
| 108 | } |
| 109 | |
| 110 | /* Given a pointer to an initialized bfd (ABFD) and a flag that indicates |
| 111 | whether or not an objfile is to be mapped (MAPPED), allocate a new objfile |
| 112 | struct, fill it in as best we can, link it into the list of all known |
| 113 | objfiles, and return a pointer to the new objfile struct. */ |
| 114 | |
| 115 | struct objfile * |
| 116 | allocate_objfile (abfd, mapped) |
| 117 | bfd *abfd; |
| 118 | int mapped; |
| 119 | { |
| 120 | struct objfile *objfile = NULL; |
| 121 | int fd; |
| 122 | void *md; |
| 123 | CORE_ADDR mapto; |
| 124 | |
| 125 | mapped |= mapped_symbol_files; |
| 126 | |
| 127 | #if !defined(NO_MMALLOC) && defined(HAVE_MMAP) |
| 128 | |
| 129 | /* If we can support mapped symbol files, try to open/reopen the mapped file |
| 130 | that corresponds to the file from which we wish to read symbols. If the |
| 131 | objfile is to be mapped, we must malloc the structure itself using the |
| 132 | mmap version, and arrange that all memory allocation for the objfile uses |
| 133 | the mmap routines. If we are reusing an existing mapped file, from which |
| 134 | we get our objfile pointer, we have to make sure that we update the |
| 135 | pointers to the alloc/free functions in the obstack, in case these |
| 136 | functions have moved within the current gdb. */ |
| 137 | |
| 138 | fd = open_mapped_file (bfd_get_filename (abfd), bfd_get_mtime (abfd), |
| 139 | mapped); |
| 140 | if (fd >= 0) |
| 141 | { |
| 142 | if (((mapto = map_to_address ()) == 0) || |
| 143 | ((md = mmalloc_attach (fd, (void *) mapto)) == NULL)) |
| 144 | { |
| 145 | close (fd); |
| 146 | } |
| 147 | else if ((objfile = (struct objfile *) mmalloc_getkey (md, 0)) != NULL) |
| 148 | { |
| 149 | /* Update memory corruption handler function addresses. */ |
| 150 | init_malloc (md); |
| 151 | objfile -> md = md; |
| 152 | objfile -> mmfd = fd; |
| 153 | /* Update pointers to functions to *our* copies */ |
| 154 | obstack_chunkfun (&objfile -> psymbol_obstack, xmmalloc); |
| 155 | obstack_freefun (&objfile -> psymbol_obstack, mfree); |
| 156 | obstack_chunkfun (&objfile -> symbol_obstack, xmmalloc); |
| 157 | obstack_freefun (&objfile -> symbol_obstack, mfree); |
| 158 | obstack_chunkfun (&objfile -> type_obstack, xmmalloc); |
| 159 | obstack_freefun (&objfile -> type_obstack, mfree); |
| 160 | /* If already in objfile list, unlink it. */ |
| 161 | unlink_objfile (objfile); |
| 162 | /* Forget things specific to a particular gdb, may have changed. */ |
| 163 | objfile -> sf = NULL; |
| 164 | } |
| 165 | else |
| 166 | { |
| 167 | /* Set up to detect internal memory corruption. MUST be done before |
| 168 | the first malloc. See comments in init_malloc() and mmcheck(). */ |
| 169 | init_malloc (md); |
| 170 | objfile = (struct objfile *) xmmalloc (md, sizeof (struct objfile)); |
| 171 | memset (objfile, 0, sizeof (struct objfile)); |
| 172 | objfile -> md = md; |
| 173 | objfile -> mmfd = fd; |
| 174 | objfile -> flags |= OBJF_MAPPED; |
| 175 | mmalloc_setkey (objfile -> md, 0, objfile); |
| 176 | obstack_specify_allocation_with_arg (&objfile -> psymbol_obstack, |
| 177 | 0, 0, xmmalloc, mfree, |
| 178 | objfile -> md); |
| 179 | obstack_specify_allocation_with_arg (&objfile -> symbol_obstack, |
| 180 | 0, 0, xmmalloc, mfree, |
| 181 | objfile -> md); |
| 182 | obstack_specify_allocation_with_arg (&objfile -> type_obstack, |
| 183 | 0, 0, xmmalloc, mfree, |
| 184 | objfile -> md); |
| 185 | } |
| 186 | } |
| 187 | |
| 188 | if (mapped && (objfile == NULL)) |
| 189 | { |
| 190 | warning ("symbol table for '%s' will not be mapped", |
| 191 | bfd_get_filename (abfd)); |
| 192 | } |
| 193 | |
| 194 | #else /* defined(NO_MMALLOC) || !defined(HAVE_MMAP) */ |
| 195 | |
| 196 | if (mapped) |
| 197 | { |
| 198 | warning ("this version of gdb does not support mapped symbol tables."); |
| 199 | |
| 200 | /* Turn off the global flag so we don't try to do mapped symbol tables |
| 201 | any more, which shuts up gdb unless the user specifically gives the |
| 202 | "mapped" keyword again. */ |
| 203 | |
| 204 | mapped_symbol_files = 0; |
| 205 | } |
| 206 | |
| 207 | #endif /* !defined(NO_MMALLOC) && defined(HAVE_MMAP) */ |
| 208 | |
| 209 | /* If we don't support mapped symbol files, didn't ask for the file to be |
| 210 | mapped, or failed to open the mapped file for some reason, then revert |
| 211 | back to an unmapped objfile. */ |
| 212 | |
| 213 | if (objfile == NULL) |
| 214 | { |
| 215 | objfile = (struct objfile *) xmalloc (sizeof (struct objfile)); |
| 216 | memset (objfile, 0, sizeof (struct objfile)); |
| 217 | objfile -> md = NULL; |
| 218 | obstack_specify_allocation (&objfile -> psymbol_obstack, 0, 0, xmalloc, |
| 219 | free); |
| 220 | obstack_specify_allocation (&objfile -> symbol_obstack, 0, 0, xmalloc, |
| 221 | free); |
| 222 | obstack_specify_allocation (&objfile -> type_obstack, 0, 0, xmalloc, |
| 223 | free); |
| 224 | } |
| 225 | |
| 226 | /* Update the per-objfile information that comes from the bfd, ensuring |
| 227 | that any data that is reference is saved in the per-objfile data |
| 228 | region. */ |
| 229 | |
| 230 | objfile -> obfd = abfd; |
| 231 | if (objfile -> name != NULL) |
| 232 | { |
| 233 | mfree (objfile -> md, objfile -> name); |
| 234 | } |
| 235 | objfile -> name = mstrsave (objfile -> md, bfd_get_filename (abfd)); |
| 236 | objfile -> mtime = bfd_get_mtime (abfd); |
| 237 | |
| 238 | /* Build section table. */ |
| 239 | |
| 240 | if (build_objfile_section_table (objfile)) |
| 241 | { |
| 242 | error ("Can't find the file sections in `%s': %s", |
| 243 | objfile -> name, bfd_errmsg (bfd_error)); |
| 244 | } |
| 245 | |
| 246 | /* Push this file onto the head of the linked list of other such files. */ |
| 247 | |
| 248 | objfile -> next = object_files; |
| 249 | object_files = objfile; |
| 250 | |
| 251 | return (objfile); |
| 252 | } |
| 253 | |
| 254 | /* Unlink OBJFILE from the list of known objfiles, if it is found in the |
| 255 | list. |
| 256 | |
| 257 | It is not a bug, or error, to call this function if OBJFILE is not known |
| 258 | to be in the current list. This is done in the case of mapped objfiles, |
| 259 | for example, just to ensure that the mapped objfile doesn't appear twice |
| 260 | in the list. Since the list is threaded, linking in a mapped objfile |
| 261 | twice would create a circular list. |
| 262 | |
| 263 | If OBJFILE turns out to be in the list, we zap it's NEXT pointer after |
| 264 | unlinking it, just to ensure that we have completely severed any linkages |
| 265 | between the OBJFILE and the list. */ |
| 266 | |
| 267 | void |
| 268 | unlink_objfile (objfile) |
| 269 | struct objfile *objfile; |
| 270 | { |
| 271 | struct objfile** objpp; |
| 272 | |
| 273 | for (objpp = &object_files; *objpp != NULL; objpp = &((*objpp) -> next)) |
| 274 | { |
| 275 | if (*objpp == objfile) |
| 276 | { |
| 277 | *objpp = (*objpp) -> next; |
| 278 | objfile -> next = NULL; |
| 279 | break; |
| 280 | } |
| 281 | } |
| 282 | } |
| 283 | |
| 284 | |
| 285 | /* Destroy an objfile and all the symtabs and psymtabs under it. Note |
| 286 | that as much as possible is allocated on the symbol_obstack and |
| 287 | psymbol_obstack, so that the memory can be efficiently freed. |
| 288 | |
| 289 | Things which we do NOT free because they are not in malloc'd memory |
| 290 | or not in memory specific to the objfile include: |
| 291 | |
| 292 | objfile -> sf |
| 293 | |
| 294 | FIXME: If the objfile is using reusable symbol information (via mmalloc), |
| 295 | then we need to take into account the fact that more than one process |
| 296 | may be using the symbol information at the same time (when mmalloc is |
| 297 | extended to support cooperative locking). When more than one process |
| 298 | is using the mapped symbol info, we need to be more careful about when |
| 299 | we free objects in the reusable area. */ |
| 300 | |
| 301 | void |
| 302 | free_objfile (objfile) |
| 303 | struct objfile *objfile; |
| 304 | { |
| 305 | int mmfd; |
| 306 | |
| 307 | /* First do any symbol file specific actions required when we are |
| 308 | finished with a particular symbol file. Note that if the objfile |
| 309 | is using reusable symbol information (via mmalloc) then each of |
| 310 | these routines is responsible for doing the correct thing, either |
| 311 | freeing things which are valid only during this particular gdb |
| 312 | execution, or leaving them to be reused during the next one. */ |
| 313 | |
| 314 | if (objfile -> sf != NULL) |
| 315 | { |
| 316 | (*objfile -> sf -> sym_finish) (objfile); |
| 317 | } |
| 318 | |
| 319 | /* We always close the bfd. */ |
| 320 | |
| 321 | if (objfile -> obfd != NULL) |
| 322 | { |
| 323 | char *name = bfd_get_filename (objfile->obfd); |
| 324 | bfd_close (objfile -> obfd); |
| 325 | free (name); |
| 326 | } |
| 327 | |
| 328 | /* Remove it from the chain of all objfiles. */ |
| 329 | |
| 330 | unlink_objfile (objfile); |
| 331 | |
| 332 | /* Before the symbol table code was redone to make it easier to |
| 333 | selectively load and remove information particular to a specific |
| 334 | linkage unit, gdb used to do these things whenever the monolithic |
| 335 | symbol table was blown away. How much still needs to be done |
| 336 | is unknown, but we play it safe for now and keep each action until |
| 337 | it is shown to be no longer needed. */ |
| 338 | |
| 339 | #if defined (CLEAR_SOLIB) |
| 340 | CLEAR_SOLIB (); |
| 341 | #endif |
| 342 | clear_pc_function_cache (); |
| 343 | |
| 344 | /* The last thing we do is free the objfile struct itself for the |
| 345 | non-reusable case, or detach from the mapped file for the reusable |
| 346 | case. Note that the mmalloc_detach or the mfree is the last thing |
| 347 | we can do with this objfile. */ |
| 348 | |
| 349 | #if !defined(NO_MMALLOC) && defined(HAVE_MMAP) |
| 350 | |
| 351 | if (objfile -> flags & OBJF_MAPPED) |
| 352 | { |
| 353 | /* Remember the fd so we can close it. We can't close it before |
| 354 | doing the detach, and after the detach the objfile is gone. */ |
| 355 | mmfd = objfile -> mmfd; |
| 356 | mmalloc_detach (objfile -> md); |
| 357 | objfile = NULL; |
| 358 | close (mmfd); |
| 359 | } |
| 360 | |
| 361 | #endif /* !defined(NO_MMALLOC) && defined(HAVE_MMAP) */ |
| 362 | |
| 363 | /* If we still have an objfile, then either we don't support reusable |
| 364 | objfiles or this one was not reusable. So free it normally. */ |
| 365 | |
| 366 | if (objfile != NULL) |
| 367 | { |
| 368 | if (objfile -> name != NULL) |
| 369 | { |
| 370 | mfree (objfile -> md, objfile -> name); |
| 371 | } |
| 372 | if (objfile->global_psymbols.list) |
| 373 | mfree (objfile->md, objfile->global_psymbols.list); |
| 374 | if (objfile->static_psymbols.list) |
| 375 | mfree (objfile->md, objfile->static_psymbols.list); |
| 376 | /* Free the obstacks for non-reusable objfiles */ |
| 377 | obstack_free (&objfile -> psymbol_obstack, 0); |
| 378 | obstack_free (&objfile -> symbol_obstack, 0); |
| 379 | obstack_free (&objfile -> type_obstack, 0); |
| 380 | mfree (objfile -> md, objfile); |
| 381 | objfile = NULL; |
| 382 | } |
| 383 | } |
| 384 | |
| 385 | |
| 386 | /* Free all the object files at once and clean up their users. */ |
| 387 | |
| 388 | void |
| 389 | free_all_objfiles () |
| 390 | { |
| 391 | struct objfile *objfile, *temp; |
| 392 | |
| 393 | ALL_OBJFILES_SAFE (objfile, temp) |
| 394 | { |
| 395 | free_objfile (objfile); |
| 396 | } |
| 397 | clear_symtab_users (); |
| 398 | } |
| 399 | \f |
| 400 | /* Relocate OBJFILE to NEW_OFFSETS. There should be OBJFILE->NUM_SECTIONS |
| 401 | entries in new_offsets. */ |
| 402 | void |
| 403 | objfile_relocate (objfile, new_offsets) |
| 404 | struct objfile *objfile; |
| 405 | struct section_offsets *new_offsets; |
| 406 | { |
| 407 | struct section_offsets *delta = (struct section_offsets *) alloca |
| 408 | (sizeof (struct section_offsets) |
| 409 | + objfile->num_sections * sizeof (delta->offsets)); |
| 410 | |
| 411 | { |
| 412 | int i; |
| 413 | int something_changed = 0; |
| 414 | for (i = 0; i < objfile->num_sections; ++i) |
| 415 | { |
| 416 | ANOFFSET (delta, i) = |
| 417 | ANOFFSET (new_offsets, i) - ANOFFSET (objfile->section_offsets, i); |
| 418 | if (ANOFFSET (delta, i) != 0) |
| 419 | something_changed = 1; |
| 420 | } |
| 421 | if (!something_changed) |
| 422 | return; |
| 423 | } |
| 424 | |
| 425 | /* OK, get all the symtabs. */ |
| 426 | { |
| 427 | struct symtab *s; |
| 428 | |
| 429 | for (s = objfile->symtabs; s; s = s->next) |
| 430 | { |
| 431 | struct linetable *l; |
| 432 | struct blockvector *bv; |
| 433 | int i; |
| 434 | |
| 435 | /* First the line table. */ |
| 436 | l = LINETABLE (s); |
| 437 | if (l) |
| 438 | { |
| 439 | for (i = 0; i < l->nitems; ++i) |
| 440 | l->item[i].pc += ANOFFSET (delta, s->block_line_section); |
| 441 | } |
| 442 | |
| 443 | /* Don't relocate a shared blockvector more than once. */ |
| 444 | if (!s->primary) |
| 445 | continue; |
| 446 | |
| 447 | bv = BLOCKVECTOR (s); |
| 448 | for (i = 0; i < BLOCKVECTOR_NBLOCKS (bv); ++i) |
| 449 | { |
| 450 | struct block *b; |
| 451 | int j; |
| 452 | |
| 453 | b = BLOCKVECTOR_BLOCK (bv, i); |
| 454 | BLOCK_START (b) += ANOFFSET (delta, s->block_line_section); |
| 455 | BLOCK_END (b) += ANOFFSET (delta, s->block_line_section); |
| 456 | |
| 457 | for (j = 0; j < BLOCK_NSYMS (b); ++j) |
| 458 | { |
| 459 | struct symbol *sym = BLOCK_SYM (b, j); |
| 460 | /* The RS6000 code from which this was taken skipped |
| 461 | any symbols in STRUCT_NAMESPACE or UNDEF_NAMESPACE. |
| 462 | But I'm leaving out that test, on the theory that |
| 463 | they can't possibly pass the tests below. */ |
| 464 | if ((SYMBOL_CLASS (sym) == LOC_LABEL |
| 465 | || SYMBOL_CLASS (sym) == LOC_STATIC) |
| 466 | && SYMBOL_SECTION (sym) >= 0) |
| 467 | { |
| 468 | SYMBOL_VALUE_ADDRESS (sym) += |
| 469 | ANOFFSET (delta, SYMBOL_SECTION (sym)); |
| 470 | } |
| 471 | } |
| 472 | } |
| 473 | } |
| 474 | } |
| 475 | |
| 476 | { |
| 477 | struct minimal_symbol *msym; |
| 478 | ALL_OBJFILE_MSYMBOLS (objfile, msym) |
| 479 | SYMBOL_VALUE_ADDRESS (msym) += ANOFFSET (delta, SYMBOL_SECTION (msym)); |
| 480 | } |
| 481 | |
| 482 | { |
| 483 | int i; |
| 484 | for (i = 0; i < objfile->num_sections; ++i) |
| 485 | ANOFFSET (objfile->section_offsets, i) = ANOFFSET (new_offsets, i); |
| 486 | } |
| 487 | } |
| 488 | \f |
| 489 | /* Many places in gdb want to test just to see if we have any partial |
| 490 | symbols available. This function returns zero if none are currently |
| 491 | available, nonzero otherwise. */ |
| 492 | |
| 493 | int |
| 494 | have_partial_symbols () |
| 495 | { |
| 496 | struct objfile *ofp; |
| 497 | |
| 498 | ALL_OBJFILES (ofp) |
| 499 | { |
| 500 | if (ofp -> psymtabs != NULL) |
| 501 | { |
| 502 | return 1; |
| 503 | } |
| 504 | } |
| 505 | return 0; |
| 506 | } |
| 507 | |
| 508 | /* Many places in gdb want to test just to see if we have any full |
| 509 | symbols available. This function returns zero if none are currently |
| 510 | available, nonzero otherwise. */ |
| 511 | |
| 512 | int |
| 513 | have_full_symbols () |
| 514 | { |
| 515 | struct objfile *ofp; |
| 516 | |
| 517 | ALL_OBJFILES (ofp) |
| 518 | { |
| 519 | if (ofp -> symtabs != NULL) |
| 520 | { |
| 521 | return 1; |
| 522 | } |
| 523 | } |
| 524 | return 0; |
| 525 | } |
| 526 | |
| 527 | /* Many places in gdb want to test just to see if we have any minimal |
| 528 | symbols available. This function returns zero if none are currently |
| 529 | available, nonzero otherwise. */ |
| 530 | |
| 531 | int |
| 532 | have_minimal_symbols () |
| 533 | { |
| 534 | struct objfile *ofp; |
| 535 | |
| 536 | ALL_OBJFILES (ofp) |
| 537 | { |
| 538 | if (ofp -> msymbols != NULL) |
| 539 | { |
| 540 | return 1; |
| 541 | } |
| 542 | } |
| 543 | return 0; |
| 544 | } |
| 545 | |
| 546 | #if !defined(NO_MMALLOC) && defined(HAVE_MMAP) |
| 547 | |
| 548 | /* Given the name of a mapped symbol file in SYMSFILENAME, and the timestamp |
| 549 | of the corresponding symbol file in MTIME, try to open an existing file |
| 550 | with the name SYMSFILENAME and verify it is more recent than the base |
| 551 | file by checking it's timestamp against MTIME. |
| 552 | |
| 553 | If SYMSFILENAME does not exist (or can't be stat'd), simply returns -1. |
| 554 | |
| 555 | If SYMSFILENAME does exist, but is out of date, we check to see if the |
| 556 | user has specified creation of a mapped file. If so, we don't issue |
| 557 | any warning message because we will be creating a new mapped file anyway, |
| 558 | overwriting the old one. If not, then we issue a warning message so that |
| 559 | the user will know why we aren't using this existing mapped symbol file. |
| 560 | In either case, we return -1. |
| 561 | |
| 562 | If SYMSFILENAME does exist and is not out of date, but can't be opened for |
| 563 | some reason, then prints an appropriate system error message and returns -1. |
| 564 | |
| 565 | Otherwise, returns the open file descriptor. */ |
| 566 | |
| 567 | static int |
| 568 | open_existing_mapped_file (symsfilename, mtime, mapped) |
| 569 | char *symsfilename; |
| 570 | long mtime; |
| 571 | int mapped; |
| 572 | { |
| 573 | int fd = -1; |
| 574 | struct stat sbuf; |
| 575 | |
| 576 | if (stat (symsfilename, &sbuf) == 0) |
| 577 | { |
| 578 | if (sbuf.st_mtime < mtime) |
| 579 | { |
| 580 | if (!mapped) |
| 581 | { |
| 582 | warning ("mapped symbol file `%s' is out of date, ignored it", |
| 583 | symsfilename); |
| 584 | } |
| 585 | } |
| 586 | else if ((fd = open (symsfilename, O_RDWR)) < 0) |
| 587 | { |
| 588 | if (error_pre_print) |
| 589 | { |
| 590 | printf (error_pre_print); |
| 591 | } |
| 592 | print_sys_errmsg (symsfilename, errno); |
| 593 | } |
| 594 | } |
| 595 | return (fd); |
| 596 | } |
| 597 | |
| 598 | /* Look for a mapped symbol file that corresponds to FILENAME and is more |
| 599 | recent than MTIME. If MAPPED is nonzero, the user has asked that gdb |
| 600 | use a mapped symbol file for this file, so create a new one if one does |
| 601 | not currently exist. |
| 602 | |
| 603 | If found, then return an open file descriptor for the file, otherwise |
| 604 | return -1. |
| 605 | |
| 606 | This routine is responsible for implementing the policy that generates |
| 607 | the name of the mapped symbol file from the name of a file containing |
| 608 | symbols that gdb would like to read. Currently this policy is to append |
| 609 | ".syms" to the name of the file. |
| 610 | |
| 611 | This routine is also responsible for implementing the policy that |
| 612 | determines where the mapped symbol file is found (the search path). |
| 613 | This policy is that when reading an existing mapped file, a file of |
| 614 | the correct name in the current directory takes precedence over a |
| 615 | file of the correct name in the same directory as the symbol file. |
| 616 | When creating a new mapped file, it is always created in the current |
| 617 | directory. This helps to minimize the chances of a user unknowingly |
| 618 | creating big mapped files in places like /bin and /usr/local/bin, and |
| 619 | allows a local copy to override a manually installed global copy (in |
| 620 | /bin for example). */ |
| 621 | |
| 622 | static int |
| 623 | open_mapped_file (filename, mtime, mapped) |
| 624 | char *filename; |
| 625 | long mtime; |
| 626 | int mapped; |
| 627 | { |
| 628 | int fd; |
| 629 | char *symsfilename; |
| 630 | |
| 631 | /* First try to open an existing file in the current directory, and |
| 632 | then try the directory where the symbol file is located. */ |
| 633 | |
| 634 | symsfilename = concat ("./", basename (filename), ".syms", (char *) NULL); |
| 635 | if ((fd = open_existing_mapped_file (symsfilename, mtime, mapped)) < 0) |
| 636 | { |
| 637 | free (symsfilename); |
| 638 | symsfilename = concat (filename, ".syms", (char *) NULL); |
| 639 | fd = open_existing_mapped_file (symsfilename, mtime, mapped); |
| 640 | } |
| 641 | |
| 642 | /* If we don't have an open file by now, then either the file does not |
| 643 | already exist, or the base file has changed since it was created. In |
| 644 | either case, if the user has specified use of a mapped file, then |
| 645 | create a new mapped file, truncating any existing one. If we can't |
| 646 | create one, print a system error message saying why we can't. |
| 647 | |
| 648 | By default the file is rw for everyone, with the user's umask taking |
| 649 | care of turning off the permissions the user wants off. */ |
| 650 | |
| 651 | if ((fd < 0) && mapped) |
| 652 | { |
| 653 | free (symsfilename); |
| 654 | symsfilename = concat ("./", basename (filename), ".syms", |
| 655 | (char *) NULL); |
| 656 | if ((fd = open (symsfilename, O_RDWR | O_CREAT | O_TRUNC, 0666)) < 0) |
| 657 | { |
| 658 | if (error_pre_print) |
| 659 | { |
| 660 | printf (error_pre_print); |
| 661 | } |
| 662 | print_sys_errmsg (symsfilename, errno); |
| 663 | } |
| 664 | } |
| 665 | |
| 666 | free (symsfilename); |
| 667 | return (fd); |
| 668 | } |
| 669 | |
| 670 | /* Return the base address at which we would like the next objfile's |
| 671 | mapped data to start. |
| 672 | |
| 673 | For now, we use the kludge that the configuration specifies a base |
| 674 | address to which it is safe to map the first mmalloc heap, and an |
| 675 | increment to add to this address for each successive heap. There are |
| 676 | a lot of issues to deal with here to make this work reasonably, including: |
| 677 | |
| 678 | Avoid memory collisions with existing mapped address spaces |
| 679 | |
| 680 | Reclaim address spaces when their mmalloc heaps are unmapped |
| 681 | |
| 682 | When mmalloc heaps are shared between processes they have to be |
| 683 | mapped at the same addresses in each |
| 684 | |
| 685 | Once created, a mmalloc heap that is to be mapped back in must be |
| 686 | mapped at the original address. I.E. each objfile will expect to |
| 687 | be remapped at it's original address. This becomes a problem if |
| 688 | the desired address is already in use. |
| 689 | |
| 690 | etc, etc, etc. |
| 691 | |
| 692 | */ |
| 693 | |
| 694 | |
| 695 | static CORE_ADDR |
| 696 | map_to_address () |
| 697 | { |
| 698 | |
| 699 | #if defined(MMAP_BASE_ADDRESS) && defined (MMAP_INCREMENT) |
| 700 | |
| 701 | static CORE_ADDR next = MMAP_BASE_ADDRESS; |
| 702 | CORE_ADDR mapto = next; |
| 703 | |
| 704 | next += MMAP_INCREMENT; |
| 705 | return (mapto); |
| 706 | |
| 707 | #else |
| 708 | |
| 709 | return (0); |
| 710 | |
| 711 | #endif |
| 712 | |
| 713 | } |
| 714 | |
| 715 | #endif /* !defined(NO_MMALLOC) && defined(HAVE_MMAP) */ |
| 716 | |
| 717 | /* Returns a section whose range includes PC or NULL if none found. */ |
| 718 | |
| 719 | struct obj_section * |
| 720 | find_pc_section(pc) |
| 721 | CORE_ADDR pc; |
| 722 | { |
| 723 | struct obj_section *s; |
| 724 | struct objfile *objfile; |
| 725 | |
| 726 | ALL_OBJFILES (objfile) |
| 727 | for (s = objfile->sections; s < objfile->sections_end; ++s) |
| 728 | if (s->addr <= pc |
| 729 | && pc < s->endaddr) |
| 730 | return(s); |
| 731 | |
| 732 | return(NULL); |
| 733 | } |