| 1 | /* Work with executable files, for GDB. |
| 2 | |
| 3 | Copyright (C) 1988-2019 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 3 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, see <http://www.gnu.org/licenses/>. */ |
| 19 | |
| 20 | #include "defs.h" |
| 21 | #include "frame.h" |
| 22 | #include "inferior.h" |
| 23 | #include "target.h" |
| 24 | #include "gdbcmd.h" |
| 25 | #include "language.h" |
| 26 | #include "filenames.h" |
| 27 | #include "symfile.h" |
| 28 | #include "objfiles.h" |
| 29 | #include "completer.h" |
| 30 | #include "value.h" |
| 31 | #include "exec.h" |
| 32 | #include "observable.h" |
| 33 | #include "arch-utils.h" |
| 34 | #include "gdbthread.h" |
| 35 | #include "progspace.h" |
| 36 | #include "gdb_bfd.h" |
| 37 | #include "gcore.h" |
| 38 | #include "source.h" |
| 39 | |
| 40 | #include <fcntl.h> |
| 41 | #include "readline/readline.h" |
| 42 | #include "gdbcore.h" |
| 43 | |
| 44 | #include <ctype.h> |
| 45 | #include <sys/stat.h> |
| 46 | #include "solist.h" |
| 47 | #include <algorithm> |
| 48 | #include "common/pathstuff.h" |
| 49 | |
| 50 | void (*deprecated_file_changed_hook) (const char *); |
| 51 | |
| 52 | static const target_info exec_target_info = { |
| 53 | "exec", |
| 54 | N_("Local exec file"), |
| 55 | N_("Use an executable file as a target.\n\ |
| 56 | Specify the filename of the executable file.") |
| 57 | }; |
| 58 | |
| 59 | /* The target vector for executable files. */ |
| 60 | |
| 61 | struct exec_target final : public target_ops |
| 62 | { |
| 63 | const target_info &info () const override |
| 64 | { return exec_target_info; } |
| 65 | |
| 66 | strata stratum () const override { return file_stratum; } |
| 67 | |
| 68 | void close () override; |
| 69 | enum target_xfer_status xfer_partial (enum target_object object, |
| 70 | const char *annex, |
| 71 | gdb_byte *readbuf, |
| 72 | const gdb_byte *writebuf, |
| 73 | ULONGEST offset, ULONGEST len, |
| 74 | ULONGEST *xfered_len) override; |
| 75 | struct target_section_table *get_section_table () override; |
| 76 | void files_info () override; |
| 77 | |
| 78 | bool has_memory () override; |
| 79 | char *make_corefile_notes (bfd *, int *) override; |
| 80 | int find_memory_regions (find_memory_region_ftype func, void *data) override; |
| 81 | }; |
| 82 | |
| 83 | static exec_target exec_ops; |
| 84 | |
| 85 | /* Whether to open exec and core files read-only or read-write. */ |
| 86 | |
| 87 | int write_files = 0; |
| 88 | static void |
| 89 | show_write_files (struct ui_file *file, int from_tty, |
| 90 | struct cmd_list_element *c, const char *value) |
| 91 | { |
| 92 | fprintf_filtered (file, _("Writing into executable and core files is %s.\n"), |
| 93 | value); |
| 94 | } |
| 95 | |
| 96 | |
| 97 | static void |
| 98 | exec_target_open (const char *args, int from_tty) |
| 99 | { |
| 100 | target_preopen (from_tty); |
| 101 | exec_file_attach (args, from_tty); |
| 102 | } |
| 103 | |
| 104 | /* Close and clear exec_bfd. If we end up with no target sections to |
| 105 | read memory from, this unpushes the exec_ops target. */ |
| 106 | |
| 107 | void |
| 108 | exec_close (void) |
| 109 | { |
| 110 | if (exec_bfd) |
| 111 | { |
| 112 | bfd *abfd = exec_bfd; |
| 113 | |
| 114 | gdb_bfd_unref (abfd); |
| 115 | |
| 116 | /* Removing target sections may close the exec_ops target. |
| 117 | Clear exec_bfd before doing so to prevent recursion. */ |
| 118 | exec_bfd = NULL; |
| 119 | exec_bfd_mtime = 0; |
| 120 | |
| 121 | remove_target_sections (&exec_bfd); |
| 122 | |
| 123 | xfree (exec_filename); |
| 124 | exec_filename = NULL; |
| 125 | } |
| 126 | } |
| 127 | |
| 128 | /* This is the target_close implementation. Clears all target |
| 129 | sections and closes all executable bfds from all program spaces. */ |
| 130 | |
| 131 | void |
| 132 | exec_target::close () |
| 133 | { |
| 134 | struct program_space *ss; |
| 135 | scoped_restore_current_program_space restore_pspace; |
| 136 | |
| 137 | ALL_PSPACES (ss) |
| 138 | { |
| 139 | set_current_program_space (ss); |
| 140 | clear_section_table (current_target_sections); |
| 141 | exec_close (); |
| 142 | } |
| 143 | } |
| 144 | |
| 145 | /* See gdbcore.h. */ |
| 146 | |
| 147 | void |
| 148 | try_open_exec_file (const char *exec_file_host, struct inferior *inf, |
| 149 | symfile_add_flags add_flags) |
| 150 | { |
| 151 | struct gdb_exception prev_err = exception_none; |
| 152 | |
| 153 | /* exec_file_attach and symbol_file_add_main may throw an error if the file |
| 154 | cannot be opened either locally or remotely. |
| 155 | |
| 156 | This happens for example, when the file is first found in the local |
| 157 | sysroot (above), and then disappears (a TOCTOU race), or when it doesn't |
| 158 | exist in the target filesystem, or when the file does exist, but |
| 159 | is not readable. |
| 160 | |
| 161 | Even without a symbol file, the remote-based debugging session should |
| 162 | continue normally instead of ending abruptly. Hence we catch thrown |
| 163 | errors/exceptions in the following code. */ |
| 164 | std::string saved_message; |
| 165 | TRY |
| 166 | { |
| 167 | /* We must do this step even if exec_file_host is NULL, so that |
| 168 | exec_file_attach will clear state. */ |
| 169 | exec_file_attach (exec_file_host, add_flags & SYMFILE_VERBOSE); |
| 170 | } |
| 171 | CATCH (err, RETURN_MASK_ERROR) |
| 172 | { |
| 173 | if (err.message != NULL) |
| 174 | warning ("%s", err.message); |
| 175 | |
| 176 | prev_err = err; |
| 177 | |
| 178 | /* Save message so it doesn't get trashed by the catch below. */ |
| 179 | if (err.message != NULL) |
| 180 | { |
| 181 | saved_message = err.message; |
| 182 | prev_err.message = saved_message.c_str (); |
| 183 | } |
| 184 | } |
| 185 | END_CATCH |
| 186 | |
| 187 | if (exec_file_host != NULL) |
| 188 | { |
| 189 | TRY |
| 190 | { |
| 191 | symbol_file_add_main (exec_file_host, add_flags); |
| 192 | } |
| 193 | CATCH (err, RETURN_MASK_ERROR) |
| 194 | { |
| 195 | if (!exception_print_same (prev_err, err)) |
| 196 | warning ("%s", err.message); |
| 197 | } |
| 198 | END_CATCH |
| 199 | } |
| 200 | } |
| 201 | |
| 202 | /* See gdbcore.h. */ |
| 203 | |
| 204 | void |
| 205 | exec_file_locate_attach (int pid, int defer_bp_reset, int from_tty) |
| 206 | { |
| 207 | char *exec_file_target; |
| 208 | symfile_add_flags add_flags = 0; |
| 209 | |
| 210 | /* Do nothing if we already have an executable filename. */ |
| 211 | if (get_exec_file (0) != NULL) |
| 212 | return; |
| 213 | |
| 214 | /* Try to determine a filename from the process itself. */ |
| 215 | exec_file_target = target_pid_to_exec_file (pid); |
| 216 | if (exec_file_target == NULL) |
| 217 | { |
| 218 | warning (_("No executable has been specified and target does not " |
| 219 | "support\n" |
| 220 | "determining executable automatically. " |
| 221 | "Try using the \"file\" command.")); |
| 222 | return; |
| 223 | } |
| 224 | |
| 225 | gdb::unique_xmalloc_ptr<char> exec_file_host |
| 226 | = exec_file_find (exec_file_target, NULL); |
| 227 | |
| 228 | if (defer_bp_reset) |
| 229 | add_flags |= SYMFILE_DEFER_BP_RESET; |
| 230 | |
| 231 | if (from_tty) |
| 232 | add_flags |= SYMFILE_VERBOSE; |
| 233 | |
| 234 | /* Attempt to open the exec file. */ |
| 235 | try_open_exec_file (exec_file_host.get (), current_inferior (), add_flags); |
| 236 | } |
| 237 | |
| 238 | /* Set FILENAME as the new exec file. |
| 239 | |
| 240 | This function is intended to be behave essentially the same |
| 241 | as exec_file_command, except that the latter will detect when |
| 242 | a target is being debugged, and will ask the user whether it |
| 243 | should be shut down first. (If the answer is "no", then the |
| 244 | new file is ignored.) |
| 245 | |
| 246 | This file is used by exec_file_command, to do the work of opening |
| 247 | and processing the exec file after any prompting has happened. |
| 248 | |
| 249 | And, it is used by child_attach, when the attach command was |
| 250 | given a pid but not a exec pathname, and the attach command could |
| 251 | figure out the pathname from the pid. (In this case, we shouldn't |
| 252 | ask the user whether the current target should be shut down -- |
| 253 | we're supplying the exec pathname late for good reason.) */ |
| 254 | |
| 255 | void |
| 256 | exec_file_attach (const char *filename, int from_tty) |
| 257 | { |
| 258 | /* First, acquire a reference to the current exec_bfd. We release |
| 259 | this at the end of the function; but acquiring it now lets the |
| 260 | BFD cache return it if this call refers to the same file. */ |
| 261 | gdb_bfd_ref_ptr exec_bfd_holder = gdb_bfd_ref_ptr::new_reference (exec_bfd); |
| 262 | |
| 263 | /* Remove any previous exec file. */ |
| 264 | exec_close (); |
| 265 | |
| 266 | /* Now open and digest the file the user requested, if any. */ |
| 267 | |
| 268 | if (!filename) |
| 269 | { |
| 270 | if (from_tty) |
| 271 | printf_unfiltered (_("No executable file now.\n")); |
| 272 | |
| 273 | set_gdbarch_from_file (NULL); |
| 274 | } |
| 275 | else |
| 276 | { |
| 277 | int load_via_target = 0; |
| 278 | const char *scratch_pathname, *canonical_pathname; |
| 279 | int scratch_chan; |
| 280 | struct target_section *sections = NULL, *sections_end = NULL; |
| 281 | char **matching; |
| 282 | |
| 283 | if (is_target_filename (filename)) |
| 284 | { |
| 285 | if (target_filesystem_is_local ()) |
| 286 | filename += strlen (TARGET_SYSROOT_PREFIX); |
| 287 | else |
| 288 | load_via_target = 1; |
| 289 | } |
| 290 | |
| 291 | gdb::unique_xmalloc_ptr<char> canonical_storage, scratch_storage; |
| 292 | if (load_via_target) |
| 293 | { |
| 294 | /* gdb_bfd_fopen does not support "target:" filenames. */ |
| 295 | if (write_files) |
| 296 | warning (_("writing into executable files is " |
| 297 | "not supported for %s sysroots"), |
| 298 | TARGET_SYSROOT_PREFIX); |
| 299 | |
| 300 | scratch_pathname = filename; |
| 301 | scratch_chan = -1; |
| 302 | canonical_pathname = scratch_pathname; |
| 303 | } |
| 304 | else |
| 305 | { |
| 306 | scratch_chan = openp (getenv ("PATH"), OPF_TRY_CWD_FIRST, |
| 307 | filename, write_files ? |
| 308 | O_RDWR | O_BINARY : O_RDONLY | O_BINARY, |
| 309 | &scratch_storage); |
| 310 | #if defined(__GO32__) || defined(_WIN32) || defined(__CYGWIN__) |
| 311 | if (scratch_chan < 0) |
| 312 | { |
| 313 | char *exename = (char *) alloca (strlen (filename) + 5); |
| 314 | |
| 315 | strcat (strcpy (exename, filename), ".exe"); |
| 316 | scratch_chan = openp (getenv ("PATH"), OPF_TRY_CWD_FIRST, |
| 317 | exename, write_files ? |
| 318 | O_RDWR | O_BINARY |
| 319 | : O_RDONLY | O_BINARY, |
| 320 | &scratch_storage); |
| 321 | } |
| 322 | #endif |
| 323 | if (scratch_chan < 0) |
| 324 | perror_with_name (filename); |
| 325 | |
| 326 | scratch_pathname = scratch_storage.get (); |
| 327 | |
| 328 | /* gdb_bfd_open (and its variants) prefers canonicalized |
| 329 | pathname for better BFD caching. */ |
| 330 | canonical_storage = gdb_realpath (scratch_pathname); |
| 331 | canonical_pathname = canonical_storage.get (); |
| 332 | } |
| 333 | |
| 334 | gdb_bfd_ref_ptr temp; |
| 335 | if (write_files && !load_via_target) |
| 336 | temp = gdb_bfd_fopen (canonical_pathname, gnutarget, |
| 337 | FOPEN_RUB, scratch_chan); |
| 338 | else |
| 339 | temp = gdb_bfd_open (canonical_pathname, gnutarget, scratch_chan); |
| 340 | exec_bfd = temp.release (); |
| 341 | |
| 342 | if (!exec_bfd) |
| 343 | { |
| 344 | error (_("\"%s\": could not open as an executable file: %s."), |
| 345 | scratch_pathname, bfd_errmsg (bfd_get_error ())); |
| 346 | } |
| 347 | |
| 348 | /* gdb_realpath_keepfile resolves symlinks on the local |
| 349 | filesystem and so cannot be used for "target:" files. */ |
| 350 | gdb_assert (exec_filename == NULL); |
| 351 | if (load_via_target) |
| 352 | exec_filename = xstrdup (bfd_get_filename (exec_bfd)); |
| 353 | else |
| 354 | exec_filename = gdb_realpath_keepfile (scratch_pathname).release (); |
| 355 | |
| 356 | if (!bfd_check_format_matches (exec_bfd, bfd_object, &matching)) |
| 357 | { |
| 358 | /* Make sure to close exec_bfd, or else "run" might try to use |
| 359 | it. */ |
| 360 | exec_close (); |
| 361 | error (_("\"%s\": not in executable format: %s"), |
| 362 | scratch_pathname, |
| 363 | gdb_bfd_errmsg (bfd_get_error (), matching).c_str ()); |
| 364 | } |
| 365 | |
| 366 | if (build_section_table (exec_bfd, §ions, §ions_end)) |
| 367 | { |
| 368 | /* Make sure to close exec_bfd, or else "run" might try to use |
| 369 | it. */ |
| 370 | exec_close (); |
| 371 | error (_("\"%s\": can't find the file sections: %s"), |
| 372 | scratch_pathname, bfd_errmsg (bfd_get_error ())); |
| 373 | } |
| 374 | |
| 375 | exec_bfd_mtime = bfd_get_mtime (exec_bfd); |
| 376 | |
| 377 | validate_files (); |
| 378 | |
| 379 | set_gdbarch_from_file (exec_bfd); |
| 380 | |
| 381 | /* Add the executable's sections to the current address spaces' |
| 382 | list of sections. This possibly pushes the exec_ops |
| 383 | target. */ |
| 384 | add_target_sections (&exec_bfd, sections, sections_end); |
| 385 | xfree (sections); |
| 386 | |
| 387 | /* Tell display code (if any) about the changed file name. */ |
| 388 | if (deprecated_exec_file_display_hook) |
| 389 | (*deprecated_exec_file_display_hook) (filename); |
| 390 | } |
| 391 | |
| 392 | bfd_cache_close_all (); |
| 393 | gdb::observers::executable_changed.notify (); |
| 394 | } |
| 395 | |
| 396 | /* Process the first arg in ARGS as the new exec file. |
| 397 | |
| 398 | Note that we have to explicitly ignore additional args, since we can |
| 399 | be called from file_command(), which also calls symbol_file_command() |
| 400 | which can take multiple args. |
| 401 | |
| 402 | If ARGS is NULL, we just want to close the exec file. */ |
| 403 | |
| 404 | static void |
| 405 | exec_file_command (const char *args, int from_tty) |
| 406 | { |
| 407 | if (from_tty && target_has_execution |
| 408 | && !query (_("A program is being debugged already.\n" |
| 409 | "Are you sure you want to change the file? "))) |
| 410 | error (_("File not changed.")); |
| 411 | |
| 412 | if (args) |
| 413 | { |
| 414 | /* Scan through the args and pick up the first non option arg |
| 415 | as the filename. */ |
| 416 | |
| 417 | gdb_argv built_argv (args); |
| 418 | char **argv = built_argv.get (); |
| 419 | |
| 420 | for (; (*argv != NULL) && (**argv == '-'); argv++) |
| 421 | {; |
| 422 | } |
| 423 | if (*argv == NULL) |
| 424 | error (_("No executable file name was specified")); |
| 425 | |
| 426 | gdb::unique_xmalloc_ptr<char> filename (tilde_expand (*argv)); |
| 427 | exec_file_attach (filename.get (), from_tty); |
| 428 | } |
| 429 | else |
| 430 | exec_file_attach (NULL, from_tty); |
| 431 | } |
| 432 | |
| 433 | /* Set both the exec file and the symbol file, in one command. |
| 434 | What a novelty. Why did GDB go through four major releases before this |
| 435 | command was added? */ |
| 436 | |
| 437 | static void |
| 438 | file_command (const char *arg, int from_tty) |
| 439 | { |
| 440 | /* FIXME, if we lose on reading the symbol file, we should revert |
| 441 | the exec file, but that's rough. */ |
| 442 | exec_file_command (arg, from_tty); |
| 443 | symbol_file_command (arg, from_tty); |
| 444 | if (deprecated_file_changed_hook) |
| 445 | deprecated_file_changed_hook (arg); |
| 446 | } |
| 447 | \f |
| 448 | |
| 449 | /* Locate all mappable sections of a BFD file. |
| 450 | table_pp_char is a char * to get it through bfd_map_over_sections; |
| 451 | we cast it back to its proper type. */ |
| 452 | |
| 453 | static void |
| 454 | add_to_section_table (bfd *abfd, struct bfd_section *asect, |
| 455 | void *table_pp_char) |
| 456 | { |
| 457 | struct target_section **table_pp = (struct target_section **) table_pp_char; |
| 458 | flagword aflag; |
| 459 | |
| 460 | gdb_assert (abfd == asect->owner); |
| 461 | |
| 462 | /* Check the section flags, but do not discard zero-length sections, since |
| 463 | some symbols may still be attached to this section. For instance, we |
| 464 | encountered on sparc-solaris 2.10 a shared library with an empty .bss |
| 465 | section to which a symbol named "_end" was attached. The address |
| 466 | of this symbol still needs to be relocated. */ |
| 467 | aflag = bfd_get_section_flags (abfd, asect); |
| 468 | if (!(aflag & SEC_ALLOC)) |
| 469 | return; |
| 470 | |
| 471 | (*table_pp)->owner = NULL; |
| 472 | (*table_pp)->the_bfd_section = asect; |
| 473 | (*table_pp)->addr = bfd_section_vma (abfd, asect); |
| 474 | (*table_pp)->endaddr = (*table_pp)->addr + bfd_section_size (abfd, asect); |
| 475 | (*table_pp)++; |
| 476 | } |
| 477 | |
| 478 | /* See exec.h. */ |
| 479 | |
| 480 | void |
| 481 | clear_section_table (struct target_section_table *table) |
| 482 | { |
| 483 | xfree (table->sections); |
| 484 | table->sections = table->sections_end = NULL; |
| 485 | } |
| 486 | |
| 487 | /* Resize section table TABLE by ADJUSTMENT. |
| 488 | ADJUSTMENT may be negative, in which case the caller must have already |
| 489 | removed the sections being deleted. |
| 490 | Returns the old size. */ |
| 491 | |
| 492 | static int |
| 493 | resize_section_table (struct target_section_table *table, int adjustment) |
| 494 | { |
| 495 | int old_count; |
| 496 | int new_count; |
| 497 | |
| 498 | old_count = table->sections_end - table->sections; |
| 499 | |
| 500 | new_count = adjustment + old_count; |
| 501 | |
| 502 | if (new_count) |
| 503 | { |
| 504 | table->sections = XRESIZEVEC (struct target_section, table->sections, |
| 505 | new_count); |
| 506 | table->sections_end = table->sections + new_count; |
| 507 | } |
| 508 | else |
| 509 | clear_section_table (table); |
| 510 | |
| 511 | return old_count; |
| 512 | } |
| 513 | |
| 514 | /* Builds a section table, given args BFD, SECTABLE_PTR, SECEND_PTR. |
| 515 | Returns 0 if OK, 1 on error. */ |
| 516 | |
| 517 | int |
| 518 | build_section_table (struct bfd *some_bfd, struct target_section **start, |
| 519 | struct target_section **end) |
| 520 | { |
| 521 | unsigned count; |
| 522 | |
| 523 | count = bfd_count_sections (some_bfd); |
| 524 | if (*start) |
| 525 | xfree (* start); |
| 526 | *start = XNEWVEC (struct target_section, count); |
| 527 | *end = *start; |
| 528 | bfd_map_over_sections (some_bfd, add_to_section_table, (char *) end); |
| 529 | if (*end > *start + count) |
| 530 | internal_error (__FILE__, __LINE__, |
| 531 | _("failed internal consistency check")); |
| 532 | /* We could realloc the table, but it probably loses for most files. */ |
| 533 | return 0; |
| 534 | } |
| 535 | |
| 536 | /* Add the sections array defined by [SECTIONS..SECTIONS_END[ to the |
| 537 | current set of target sections. */ |
| 538 | |
| 539 | void |
| 540 | add_target_sections (void *owner, |
| 541 | struct target_section *sections, |
| 542 | struct target_section *sections_end) |
| 543 | { |
| 544 | int count; |
| 545 | struct target_section_table *table = current_target_sections; |
| 546 | |
| 547 | count = sections_end - sections; |
| 548 | |
| 549 | if (count > 0) |
| 550 | { |
| 551 | int space = resize_section_table (table, count); |
| 552 | int i; |
| 553 | |
| 554 | for (i = 0; i < count; ++i) |
| 555 | { |
| 556 | table->sections[space + i] = sections[i]; |
| 557 | table->sections[space + i].owner = owner; |
| 558 | } |
| 559 | |
| 560 | /* If these are the first file sections we can provide memory |
| 561 | from, push the file_stratum target. */ |
| 562 | if (!target_is_pushed (&exec_ops)) |
| 563 | push_target (&exec_ops); |
| 564 | } |
| 565 | } |
| 566 | |
| 567 | /* Add the sections of OBJFILE to the current set of target sections. */ |
| 568 | |
| 569 | void |
| 570 | add_target_sections_of_objfile (struct objfile *objfile) |
| 571 | { |
| 572 | struct target_section_table *table = current_target_sections; |
| 573 | struct obj_section *osect; |
| 574 | int space; |
| 575 | unsigned count = 0; |
| 576 | struct target_section *ts; |
| 577 | |
| 578 | if (objfile == NULL) |
| 579 | return; |
| 580 | |
| 581 | /* Compute the number of sections to add. */ |
| 582 | ALL_OBJFILE_OSECTIONS (objfile, osect) |
| 583 | { |
| 584 | if (bfd_get_section_size (osect->the_bfd_section) == 0) |
| 585 | continue; |
| 586 | count++; |
| 587 | } |
| 588 | |
| 589 | if (count == 0) |
| 590 | return; |
| 591 | |
| 592 | space = resize_section_table (table, count); |
| 593 | |
| 594 | ts = table->sections + space; |
| 595 | |
| 596 | ALL_OBJFILE_OSECTIONS (objfile, osect) |
| 597 | { |
| 598 | if (bfd_get_section_size (osect->the_bfd_section) == 0) |
| 599 | continue; |
| 600 | |
| 601 | gdb_assert (ts < table->sections + space + count); |
| 602 | |
| 603 | ts->addr = obj_section_addr (osect); |
| 604 | ts->endaddr = obj_section_endaddr (osect); |
| 605 | ts->the_bfd_section = osect->the_bfd_section; |
| 606 | ts->owner = (void *) objfile; |
| 607 | |
| 608 | ts++; |
| 609 | } |
| 610 | } |
| 611 | |
| 612 | /* Remove all target sections owned by OWNER. |
| 613 | OWNER must be the same value passed to add_target_sections. */ |
| 614 | |
| 615 | void |
| 616 | remove_target_sections (void *owner) |
| 617 | { |
| 618 | struct target_section *src, *dest; |
| 619 | struct target_section_table *table = current_target_sections; |
| 620 | |
| 621 | gdb_assert (owner != NULL); |
| 622 | |
| 623 | dest = table->sections; |
| 624 | for (src = table->sections; src < table->sections_end; src++) |
| 625 | if (src->owner != owner) |
| 626 | { |
| 627 | /* Keep this section. */ |
| 628 | if (dest < src) |
| 629 | *dest = *src; |
| 630 | dest++; |
| 631 | } |
| 632 | |
| 633 | /* If we've dropped any sections, resize the section table. */ |
| 634 | if (dest < src) |
| 635 | { |
| 636 | int old_count; |
| 637 | |
| 638 | old_count = resize_section_table (table, dest - src); |
| 639 | |
| 640 | /* If we don't have any more sections to read memory from, |
| 641 | remove the file_stratum target from the stack. */ |
| 642 | if (old_count + (dest - src) == 0) |
| 643 | { |
| 644 | struct program_space *pspace; |
| 645 | |
| 646 | ALL_PSPACES (pspace) |
| 647 | if (pspace->target_sections.sections |
| 648 | != pspace->target_sections.sections_end) |
| 649 | return; |
| 650 | |
| 651 | unpush_target (&exec_ops); |
| 652 | } |
| 653 | } |
| 654 | } |
| 655 | |
| 656 | \f |
| 657 | |
| 658 | enum target_xfer_status |
| 659 | exec_read_partial_read_only (gdb_byte *readbuf, ULONGEST offset, |
| 660 | ULONGEST len, ULONGEST *xfered_len) |
| 661 | { |
| 662 | /* It's unduly pedantic to refuse to look at the executable for |
| 663 | read-only pieces; so do the equivalent of readonly regions aka |
| 664 | QTro packet. */ |
| 665 | if (exec_bfd != NULL) |
| 666 | { |
| 667 | asection *s; |
| 668 | bfd_size_type size; |
| 669 | bfd_vma vma; |
| 670 | |
| 671 | for (s = exec_bfd->sections; s; s = s->next) |
| 672 | { |
| 673 | if ((s->flags & SEC_LOAD) == 0 |
| 674 | || (s->flags & SEC_READONLY) == 0) |
| 675 | continue; |
| 676 | |
| 677 | vma = s->vma; |
| 678 | size = bfd_get_section_size (s); |
| 679 | if (vma <= offset && offset < (vma + size)) |
| 680 | { |
| 681 | ULONGEST amt; |
| 682 | |
| 683 | amt = (vma + size) - offset; |
| 684 | if (amt > len) |
| 685 | amt = len; |
| 686 | |
| 687 | amt = bfd_get_section_contents (exec_bfd, s, |
| 688 | readbuf, offset - vma, amt); |
| 689 | |
| 690 | if (amt == 0) |
| 691 | return TARGET_XFER_EOF; |
| 692 | else |
| 693 | { |
| 694 | *xfered_len = amt; |
| 695 | return TARGET_XFER_OK; |
| 696 | } |
| 697 | } |
| 698 | } |
| 699 | } |
| 700 | |
| 701 | /* Indicate failure to find the requested memory block. */ |
| 702 | return TARGET_XFER_E_IO; |
| 703 | } |
| 704 | |
| 705 | /* Return all read-only memory ranges found in the target section |
| 706 | table defined by SECTIONS and SECTIONS_END, starting at (and |
| 707 | intersected with) MEMADDR for LEN bytes. */ |
| 708 | |
| 709 | static std::vector<mem_range> |
| 710 | section_table_available_memory (CORE_ADDR memaddr, ULONGEST len, |
| 711 | struct target_section *sections, |
| 712 | struct target_section *sections_end) |
| 713 | { |
| 714 | std::vector<mem_range> memory; |
| 715 | |
| 716 | for (target_section *p = sections; p < sections_end; p++) |
| 717 | { |
| 718 | if ((bfd_get_section_flags (p->the_bfd_section->owner, |
| 719 | p->the_bfd_section) |
| 720 | & SEC_READONLY) == 0) |
| 721 | continue; |
| 722 | |
| 723 | /* Copy the meta-data, adjusted. */ |
| 724 | if (mem_ranges_overlap (p->addr, p->endaddr - p->addr, memaddr, len)) |
| 725 | { |
| 726 | ULONGEST lo1, hi1, lo2, hi2; |
| 727 | |
| 728 | lo1 = memaddr; |
| 729 | hi1 = memaddr + len; |
| 730 | |
| 731 | lo2 = p->addr; |
| 732 | hi2 = p->endaddr; |
| 733 | |
| 734 | CORE_ADDR start = std::max (lo1, lo2); |
| 735 | int length = std::min (hi1, hi2) - start; |
| 736 | |
| 737 | memory.emplace_back (start, length); |
| 738 | } |
| 739 | } |
| 740 | |
| 741 | return memory; |
| 742 | } |
| 743 | |
| 744 | enum target_xfer_status |
| 745 | section_table_read_available_memory (gdb_byte *readbuf, ULONGEST offset, |
| 746 | ULONGEST len, ULONGEST *xfered_len) |
| 747 | { |
| 748 | target_section_table *table = target_get_section_table (&exec_ops); |
| 749 | std::vector<mem_range> available_memory |
| 750 | = section_table_available_memory (offset, len, |
| 751 | table->sections, table->sections_end); |
| 752 | |
| 753 | normalize_mem_ranges (&available_memory); |
| 754 | |
| 755 | for (const mem_range &r : available_memory) |
| 756 | { |
| 757 | if (mem_ranges_overlap (r.start, r.length, offset, len)) |
| 758 | { |
| 759 | CORE_ADDR end; |
| 760 | enum target_xfer_status status; |
| 761 | |
| 762 | /* Get the intersection window. */ |
| 763 | end = std::min<CORE_ADDR> (offset + len, r.start + r.length); |
| 764 | |
| 765 | gdb_assert (end - offset <= len); |
| 766 | |
| 767 | if (offset >= r.start) |
| 768 | status = exec_read_partial_read_only (readbuf, offset, |
| 769 | end - offset, |
| 770 | xfered_len); |
| 771 | else |
| 772 | { |
| 773 | *xfered_len = r.start - offset; |
| 774 | status = TARGET_XFER_UNAVAILABLE; |
| 775 | } |
| 776 | return status; |
| 777 | } |
| 778 | } |
| 779 | |
| 780 | *xfered_len = len; |
| 781 | return TARGET_XFER_UNAVAILABLE; |
| 782 | } |
| 783 | |
| 784 | enum target_xfer_status |
| 785 | section_table_xfer_memory_partial (gdb_byte *readbuf, const gdb_byte *writebuf, |
| 786 | ULONGEST offset, ULONGEST len, |
| 787 | ULONGEST *xfered_len, |
| 788 | struct target_section *sections, |
| 789 | struct target_section *sections_end, |
| 790 | const char *section_name) |
| 791 | { |
| 792 | int res; |
| 793 | struct target_section *p; |
| 794 | ULONGEST memaddr = offset; |
| 795 | ULONGEST memend = memaddr + len; |
| 796 | |
| 797 | if (len == 0) |
| 798 | internal_error (__FILE__, __LINE__, |
| 799 | _("failed internal consistency check")); |
| 800 | |
| 801 | for (p = sections; p < sections_end; p++) |
| 802 | { |
| 803 | struct bfd_section *asect = p->the_bfd_section; |
| 804 | bfd *abfd = asect->owner; |
| 805 | |
| 806 | if (section_name && strcmp (section_name, asect->name) != 0) |
| 807 | continue; /* not the section we need. */ |
| 808 | if (memaddr >= p->addr) |
| 809 | { |
| 810 | if (memend <= p->endaddr) |
| 811 | { |
| 812 | /* Entire transfer is within this section. */ |
| 813 | if (writebuf) |
| 814 | res = bfd_set_section_contents (abfd, asect, |
| 815 | writebuf, memaddr - p->addr, |
| 816 | len); |
| 817 | else |
| 818 | res = bfd_get_section_contents (abfd, asect, |
| 819 | readbuf, memaddr - p->addr, |
| 820 | len); |
| 821 | |
| 822 | if (res != 0) |
| 823 | { |
| 824 | *xfered_len = len; |
| 825 | return TARGET_XFER_OK; |
| 826 | } |
| 827 | else |
| 828 | return TARGET_XFER_EOF; |
| 829 | } |
| 830 | else if (memaddr >= p->endaddr) |
| 831 | { |
| 832 | /* This section ends before the transfer starts. */ |
| 833 | continue; |
| 834 | } |
| 835 | else |
| 836 | { |
| 837 | /* This section overlaps the transfer. Just do half. */ |
| 838 | len = p->endaddr - memaddr; |
| 839 | if (writebuf) |
| 840 | res = bfd_set_section_contents (abfd, asect, |
| 841 | writebuf, memaddr - p->addr, |
| 842 | len); |
| 843 | else |
| 844 | res = bfd_get_section_contents (abfd, asect, |
| 845 | readbuf, memaddr - p->addr, |
| 846 | len); |
| 847 | if (res != 0) |
| 848 | { |
| 849 | *xfered_len = len; |
| 850 | return TARGET_XFER_OK; |
| 851 | } |
| 852 | else |
| 853 | return TARGET_XFER_EOF; |
| 854 | } |
| 855 | } |
| 856 | } |
| 857 | |
| 858 | return TARGET_XFER_EOF; /* We can't help. */ |
| 859 | } |
| 860 | |
| 861 | struct target_section_table * |
| 862 | exec_target::get_section_table () |
| 863 | { |
| 864 | return current_target_sections; |
| 865 | } |
| 866 | |
| 867 | enum target_xfer_status |
| 868 | exec_target::xfer_partial (enum target_object object, |
| 869 | const char *annex, gdb_byte *readbuf, |
| 870 | const gdb_byte *writebuf, |
| 871 | ULONGEST offset, ULONGEST len, ULONGEST *xfered_len) |
| 872 | { |
| 873 | struct target_section_table *table = get_section_table (); |
| 874 | |
| 875 | if (object == TARGET_OBJECT_MEMORY) |
| 876 | return section_table_xfer_memory_partial (readbuf, writebuf, |
| 877 | offset, len, xfered_len, |
| 878 | table->sections, |
| 879 | table->sections_end, |
| 880 | NULL); |
| 881 | else |
| 882 | return TARGET_XFER_E_IO; |
| 883 | } |
| 884 | \f |
| 885 | |
| 886 | void |
| 887 | print_section_info (struct target_section_table *t, bfd *abfd) |
| 888 | { |
| 889 | struct gdbarch *gdbarch = gdbarch_from_bfd (abfd); |
| 890 | struct target_section *p; |
| 891 | /* FIXME: 16 is not wide enough when gdbarch_addr_bit > 64. */ |
| 892 | int wid = gdbarch_addr_bit (gdbarch) <= 32 ? 8 : 16; |
| 893 | |
| 894 | printf_filtered ("\t`%s', ", bfd_get_filename (abfd)); |
| 895 | wrap_here (" "); |
| 896 | printf_filtered (_("file type %s.\n"), bfd_get_target (abfd)); |
| 897 | if (abfd == exec_bfd) |
| 898 | { |
| 899 | /* gcc-3.4 does not like the initialization in |
| 900 | <p == t->sections_end>. */ |
| 901 | bfd_vma displacement = 0; |
| 902 | bfd_vma entry_point; |
| 903 | |
| 904 | for (p = t->sections; p < t->sections_end; p++) |
| 905 | { |
| 906 | struct bfd_section *psect = p->the_bfd_section; |
| 907 | bfd *pbfd = psect->owner; |
| 908 | |
| 909 | if ((bfd_get_section_flags (pbfd, psect) & (SEC_ALLOC | SEC_LOAD)) |
| 910 | != (SEC_ALLOC | SEC_LOAD)) |
| 911 | continue; |
| 912 | |
| 913 | if (bfd_get_section_vma (pbfd, psect) <= abfd->start_address |
| 914 | && abfd->start_address < (bfd_get_section_vma (pbfd, psect) |
| 915 | + bfd_get_section_size (psect))) |
| 916 | { |
| 917 | displacement = p->addr - bfd_get_section_vma (pbfd, psect); |
| 918 | break; |
| 919 | } |
| 920 | } |
| 921 | if (p == t->sections_end) |
| 922 | warning (_("Cannot find section for the entry point of %s."), |
| 923 | bfd_get_filename (abfd)); |
| 924 | |
| 925 | entry_point = gdbarch_addr_bits_remove (gdbarch, |
| 926 | bfd_get_start_address (abfd) |
| 927 | + displacement); |
| 928 | printf_filtered (_("\tEntry point: %s\n"), |
| 929 | paddress (gdbarch, entry_point)); |
| 930 | } |
| 931 | for (p = t->sections; p < t->sections_end; p++) |
| 932 | { |
| 933 | struct bfd_section *psect = p->the_bfd_section; |
| 934 | bfd *pbfd = psect->owner; |
| 935 | |
| 936 | printf_filtered ("\t%s", hex_string_custom (p->addr, wid)); |
| 937 | printf_filtered (" - %s", hex_string_custom (p->endaddr, wid)); |
| 938 | |
| 939 | /* FIXME: A format of "08l" is not wide enough for file offsets |
| 940 | larger than 4GB. OTOH, making it "016l" isn't desirable either |
| 941 | since most output will then be much wider than necessary. It |
| 942 | may make sense to test the size of the file and choose the |
| 943 | format string accordingly. */ |
| 944 | /* FIXME: i18n: Need to rewrite this sentence. */ |
| 945 | if (info_verbose) |
| 946 | printf_filtered (" @ %s", |
| 947 | hex_string_custom (psect->filepos, 8)); |
| 948 | printf_filtered (" is %s", bfd_section_name (pbfd, psect)); |
| 949 | if (pbfd != abfd) |
| 950 | printf_filtered (" in %s", bfd_get_filename (pbfd)); |
| 951 | printf_filtered ("\n"); |
| 952 | } |
| 953 | } |
| 954 | |
| 955 | void |
| 956 | exec_target::files_info () |
| 957 | { |
| 958 | if (exec_bfd) |
| 959 | print_section_info (current_target_sections, exec_bfd); |
| 960 | else |
| 961 | puts_filtered (_("\t<no file loaded>\n")); |
| 962 | } |
| 963 | |
| 964 | static void |
| 965 | set_section_command (const char *args, int from_tty) |
| 966 | { |
| 967 | struct target_section *p; |
| 968 | const char *secname; |
| 969 | unsigned seclen; |
| 970 | unsigned long secaddr; |
| 971 | char secprint[100]; |
| 972 | long offset; |
| 973 | struct target_section_table *table; |
| 974 | |
| 975 | if (args == 0) |
| 976 | error (_("Must specify section name and its virtual address")); |
| 977 | |
| 978 | /* Parse out section name. */ |
| 979 | for (secname = args; !isspace (*args); args++); |
| 980 | seclen = args - secname; |
| 981 | |
| 982 | /* Parse out new virtual address. */ |
| 983 | secaddr = parse_and_eval_address (args); |
| 984 | |
| 985 | table = current_target_sections; |
| 986 | for (p = table->sections; p < table->sections_end; p++) |
| 987 | { |
| 988 | if (!strncmp (secname, bfd_section_name (p->bfd, |
| 989 | p->the_bfd_section), seclen) |
| 990 | && bfd_section_name (p->bfd, p->the_bfd_section)[seclen] == '\0') |
| 991 | { |
| 992 | offset = secaddr - p->addr; |
| 993 | p->addr += offset; |
| 994 | p->endaddr += offset; |
| 995 | if (from_tty) |
| 996 | exec_ops.files_info (); |
| 997 | return; |
| 998 | } |
| 999 | } |
| 1000 | if (seclen >= sizeof (secprint)) |
| 1001 | seclen = sizeof (secprint) - 1; |
| 1002 | strncpy (secprint, secname, seclen); |
| 1003 | secprint[seclen] = '\0'; |
| 1004 | error (_("Section %s not found"), secprint); |
| 1005 | } |
| 1006 | |
| 1007 | /* If we can find a section in FILENAME with BFD index INDEX, adjust |
| 1008 | it to ADDRESS. */ |
| 1009 | |
| 1010 | void |
| 1011 | exec_set_section_address (const char *filename, int index, CORE_ADDR address) |
| 1012 | { |
| 1013 | struct target_section *p; |
| 1014 | struct target_section_table *table; |
| 1015 | |
| 1016 | table = current_target_sections; |
| 1017 | for (p = table->sections; p < table->sections_end; p++) |
| 1018 | { |
| 1019 | if (filename_cmp (filename, p->the_bfd_section->owner->filename) == 0 |
| 1020 | && index == p->the_bfd_section->index) |
| 1021 | { |
| 1022 | p->endaddr += address - p->addr; |
| 1023 | p->addr = address; |
| 1024 | } |
| 1025 | } |
| 1026 | } |
| 1027 | |
| 1028 | bool |
| 1029 | exec_target::has_memory () |
| 1030 | { |
| 1031 | /* We can provide memory if we have any file/target sections to read |
| 1032 | from. */ |
| 1033 | return (current_target_sections->sections |
| 1034 | != current_target_sections->sections_end); |
| 1035 | } |
| 1036 | |
| 1037 | char * |
| 1038 | exec_target::make_corefile_notes (bfd *obfd, int *note_size) |
| 1039 | { |
| 1040 | error (_("Can't create a corefile")); |
| 1041 | } |
| 1042 | |
| 1043 | int |
| 1044 | exec_target::find_memory_regions (find_memory_region_ftype func, void *data) |
| 1045 | { |
| 1046 | return objfile_find_memory_regions (this, func, data); |
| 1047 | } |
| 1048 | |
| 1049 | void |
| 1050 | _initialize_exec (void) |
| 1051 | { |
| 1052 | struct cmd_list_element *c; |
| 1053 | |
| 1054 | if (!dbx_commands) |
| 1055 | { |
| 1056 | c = add_cmd ("file", class_files, file_command, _("\ |
| 1057 | Use FILE as program to be debugged.\n\ |
| 1058 | It is read for its symbols, for getting the contents of pure memory,\n\ |
| 1059 | and it is the program executed when you use the `run' command.\n\ |
| 1060 | If FILE cannot be found as specified, your execution directory path\n\ |
| 1061 | ($PATH) is searched for a command of that name.\n\ |
| 1062 | No arg means to have no executable file and no symbols."), &cmdlist); |
| 1063 | set_cmd_completer (c, filename_completer); |
| 1064 | } |
| 1065 | |
| 1066 | c = add_cmd ("exec-file", class_files, exec_file_command, _("\ |
| 1067 | Use FILE as program for getting contents of pure memory.\n\ |
| 1068 | If FILE cannot be found as specified, your execution directory path\n\ |
| 1069 | is searched for a command of that name.\n\ |
| 1070 | No arg means have no executable file."), &cmdlist); |
| 1071 | set_cmd_completer (c, filename_completer); |
| 1072 | |
| 1073 | add_com ("section", class_files, set_section_command, _("\ |
| 1074 | Change the base address of section SECTION of the exec file to ADDR.\n\ |
| 1075 | This can be used if the exec file does not contain section addresses,\n\ |
| 1076 | (such as in the a.out format), or when the addresses specified in the\n\ |
| 1077 | file itself are wrong. Each section must be changed separately. The\n\ |
| 1078 | ``info files'' command lists all the sections and their addresses.")); |
| 1079 | |
| 1080 | add_setshow_boolean_cmd ("write", class_support, &write_files, _("\ |
| 1081 | Set writing into executable and core files."), _("\ |
| 1082 | Show writing into executable and core files."), NULL, |
| 1083 | NULL, |
| 1084 | show_write_files, |
| 1085 | &setlist, &showlist); |
| 1086 | |
| 1087 | add_target (exec_target_info, exec_target_open, filename_completer); |
| 1088 | } |