| 1 | /* Core dump and executable file functions above target vector, for GDB. |
| 2 | |
| 3 | Copyright (C) 1986-2014 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 <string.h> |
| 22 | #include <errno.h> |
| 23 | #include <signal.h> |
| 24 | #include <fcntl.h> |
| 25 | #include "inferior.h" |
| 26 | #include "symtab.h" |
| 27 | #include "command.h" |
| 28 | #include "gdbcmd.h" |
| 29 | #include "bfd.h" |
| 30 | #include "target.h" |
| 31 | #include "gdbcore.h" |
| 32 | #include "dis-asm.h" |
| 33 | #include <sys/stat.h> |
| 34 | #include "completer.h" |
| 35 | #include "exceptions.h" |
| 36 | #include "observer.h" |
| 37 | #include "cli/cli-utils.h" |
| 38 | |
| 39 | /* Local function declarations. */ |
| 40 | |
| 41 | extern void _initialize_core (void); |
| 42 | static void call_extra_exec_file_hooks (char *filename); |
| 43 | |
| 44 | /* You can have any number of hooks for `exec_file_command' command to |
| 45 | call. If there's only one hook, it is set in exec_file_display |
| 46 | hook. If there are two or more hooks, they are set in |
| 47 | exec_file_extra_hooks[], and deprecated_exec_file_display_hook is |
| 48 | set to a function that calls all of them. This extra complexity is |
| 49 | needed to preserve compatibility with old code that assumed that |
| 50 | only one hook could be set, and which called |
| 51 | deprecated_exec_file_display_hook directly. */ |
| 52 | |
| 53 | typedef void (*hook_type) (char *); |
| 54 | |
| 55 | hook_type deprecated_exec_file_display_hook; /* The original hook. */ |
| 56 | static hook_type *exec_file_extra_hooks; /* Array of additional |
| 57 | hooks. */ |
| 58 | static int exec_file_hook_count = 0; /* Size of array. */ |
| 59 | |
| 60 | /* Binary file diddling handle for the core file. */ |
| 61 | |
| 62 | bfd *core_bfd = NULL; |
| 63 | |
| 64 | /* corelow.c target. It is never NULL after GDB initialization. */ |
| 65 | |
| 66 | struct target_ops *core_target; |
| 67 | \f |
| 68 | |
| 69 | /* Backward compatability with old way of specifying core files. */ |
| 70 | |
| 71 | void |
| 72 | core_file_command (char *filename, int from_tty) |
| 73 | { |
| 74 | dont_repeat (); /* Either way, seems bogus. */ |
| 75 | |
| 76 | gdb_assert (core_target != NULL); |
| 77 | |
| 78 | if (!filename) |
| 79 | (core_target->to_detach) (core_target, filename, from_tty); |
| 80 | else |
| 81 | (core_target->to_open) (filename, from_tty); |
| 82 | } |
| 83 | \f |
| 84 | |
| 85 | /* If there are two or more functions that wish to hook into |
| 86 | exec_file_command, this function will call all of the hook |
| 87 | functions. */ |
| 88 | |
| 89 | static void |
| 90 | call_extra_exec_file_hooks (char *filename) |
| 91 | { |
| 92 | int i; |
| 93 | |
| 94 | for (i = 0; i < exec_file_hook_count; i++) |
| 95 | (*exec_file_extra_hooks[i]) (filename); |
| 96 | } |
| 97 | |
| 98 | /* Call this to specify the hook for exec_file_command to call back. |
| 99 | This is called from the x-window display code. */ |
| 100 | |
| 101 | void |
| 102 | specify_exec_file_hook (void (*hook) (char *)) |
| 103 | { |
| 104 | hook_type *new_array; |
| 105 | |
| 106 | if (deprecated_exec_file_display_hook != NULL) |
| 107 | { |
| 108 | /* There's already a hook installed. Arrange to have both it |
| 109 | and the subsequent hooks called. */ |
| 110 | if (exec_file_hook_count == 0) |
| 111 | { |
| 112 | /* If this is the first extra hook, initialize the hook |
| 113 | array. */ |
| 114 | exec_file_extra_hooks = (hook_type *) |
| 115 | xmalloc (sizeof (hook_type)); |
| 116 | exec_file_extra_hooks[0] = deprecated_exec_file_display_hook; |
| 117 | deprecated_exec_file_display_hook = call_extra_exec_file_hooks; |
| 118 | exec_file_hook_count = 1; |
| 119 | } |
| 120 | |
| 121 | /* Grow the hook array by one and add the new hook to the end. |
| 122 | Yes, it's inefficient to grow it by one each time but since |
| 123 | this is hardly ever called it's not a big deal. */ |
| 124 | exec_file_hook_count++; |
| 125 | new_array = (hook_type *) |
| 126 | xrealloc (exec_file_extra_hooks, |
| 127 | exec_file_hook_count * sizeof (hook_type)); |
| 128 | exec_file_extra_hooks = new_array; |
| 129 | exec_file_extra_hooks[exec_file_hook_count - 1] = hook; |
| 130 | } |
| 131 | else |
| 132 | deprecated_exec_file_display_hook = hook; |
| 133 | } |
| 134 | |
| 135 | void |
| 136 | reopen_exec_file (void) |
| 137 | { |
| 138 | char *filename; |
| 139 | int res; |
| 140 | struct stat st; |
| 141 | struct cleanup *cleanups; |
| 142 | |
| 143 | /* Don't do anything if there isn't an exec file. */ |
| 144 | if (exec_bfd == NULL) |
| 145 | return; |
| 146 | |
| 147 | /* If the timestamp of the exec file has changed, reopen it. */ |
| 148 | filename = xstrdup (bfd_get_filename (exec_bfd)); |
| 149 | cleanups = make_cleanup (xfree, filename); |
| 150 | res = stat (filename, &st); |
| 151 | |
| 152 | if (exec_bfd_mtime && exec_bfd_mtime != st.st_mtime) |
| 153 | exec_file_attach (filename, 0); |
| 154 | else |
| 155 | /* If we accessed the file since last opening it, close it now; |
| 156 | this stops GDB from holding the executable open after it |
| 157 | exits. */ |
| 158 | bfd_cache_close_all (); |
| 159 | |
| 160 | do_cleanups (cleanups); |
| 161 | } |
| 162 | \f |
| 163 | /* If we have both a core file and an exec file, |
| 164 | print a warning if they don't go together. */ |
| 165 | |
| 166 | void |
| 167 | validate_files (void) |
| 168 | { |
| 169 | if (exec_bfd && core_bfd) |
| 170 | { |
| 171 | if (!core_file_matches_executable_p (core_bfd, exec_bfd)) |
| 172 | warning (_("core file may not match specified executable file.")); |
| 173 | else if (bfd_get_mtime (exec_bfd) > bfd_get_mtime (core_bfd)) |
| 174 | warning (_("exec file is newer than core file.")); |
| 175 | } |
| 176 | } |
| 177 | |
| 178 | /* Return the name of the executable file as a string. |
| 179 | ERR nonzero means get error if there is none specified; |
| 180 | otherwise return 0 in that case. */ |
| 181 | |
| 182 | char * |
| 183 | get_exec_file (int err) |
| 184 | { |
| 185 | if (exec_filename) |
| 186 | return exec_filename; |
| 187 | if (!err) |
| 188 | return NULL; |
| 189 | |
| 190 | error (_("No executable file specified.\n\ |
| 191 | Use the \"file\" or \"exec-file\" command.")); |
| 192 | return NULL; |
| 193 | } |
| 194 | \f |
| 195 | |
| 196 | char * |
| 197 | memory_error_message (enum target_xfer_status err, |
| 198 | struct gdbarch *gdbarch, CORE_ADDR memaddr) |
| 199 | { |
| 200 | switch (err) |
| 201 | { |
| 202 | case TARGET_XFER_E_IO: |
| 203 | /* Actually, address between memaddr and memaddr + len was out of |
| 204 | bounds. */ |
| 205 | return xstrprintf (_("Cannot access memory at address %s"), |
| 206 | paddress (gdbarch, memaddr)); |
| 207 | case TARGET_XFER_E_UNAVAILABLE: |
| 208 | return xstrprintf (_("Memory at address %s unavailable."), |
| 209 | paddress (gdbarch, memaddr)); |
| 210 | default: |
| 211 | internal_error (__FILE__, __LINE__, |
| 212 | "unhandled target_xfer_status: %s (%s)", |
| 213 | target_xfer_status_to_string (err), |
| 214 | plongest (err)); |
| 215 | } |
| 216 | } |
| 217 | |
| 218 | /* Report a memory error by throwing a suitable exception. */ |
| 219 | |
| 220 | void |
| 221 | memory_error (enum target_xfer_status err, CORE_ADDR memaddr) |
| 222 | { |
| 223 | char *str; |
| 224 | enum errors exception = GDB_NO_ERROR; |
| 225 | |
| 226 | /* Build error string. */ |
| 227 | str = memory_error_message (err, target_gdbarch (), memaddr); |
| 228 | make_cleanup (xfree, str); |
| 229 | |
| 230 | /* Choose the right error to throw. */ |
| 231 | switch (err) |
| 232 | { |
| 233 | case TARGET_XFER_E_IO: |
| 234 | exception = MEMORY_ERROR; |
| 235 | break; |
| 236 | case TARGET_XFER_E_UNAVAILABLE: |
| 237 | exception = NOT_AVAILABLE_ERROR; |
| 238 | break; |
| 239 | } |
| 240 | |
| 241 | /* Throw it. */ |
| 242 | throw_error (exception, ("%s"), str); |
| 243 | } |
| 244 | |
| 245 | /* Same as target_read_memory, but report an error if can't read. */ |
| 246 | |
| 247 | void |
| 248 | read_memory (CORE_ADDR memaddr, gdb_byte *myaddr, ssize_t len) |
| 249 | { |
| 250 | ULONGEST xfered = 0; |
| 251 | |
| 252 | while (xfered < len) |
| 253 | { |
| 254 | enum target_xfer_status status; |
| 255 | ULONGEST xfered_len; |
| 256 | |
| 257 | status = target_xfer_partial (current_target.beneath, |
| 258 | TARGET_OBJECT_MEMORY, NULL, |
| 259 | myaddr + xfered, NULL, |
| 260 | memaddr + xfered, len - xfered, |
| 261 | &xfered_len); |
| 262 | |
| 263 | if (status == TARGET_XFER_EOF) |
| 264 | memory_error (TARGET_XFER_E_IO, memaddr + xfered); |
| 265 | |
| 266 | if (TARGET_XFER_STATUS_ERROR_P (status)) |
| 267 | memory_error (status, memaddr + xfered); |
| 268 | |
| 269 | gdb_assert (status == TARGET_XFER_OK); |
| 270 | xfered += xfered_len; |
| 271 | QUIT; |
| 272 | } |
| 273 | } |
| 274 | |
| 275 | /* Same as target_read_stack, but report an error if can't read. */ |
| 276 | |
| 277 | void |
| 278 | read_stack (CORE_ADDR memaddr, gdb_byte *myaddr, ssize_t len) |
| 279 | { |
| 280 | int status; |
| 281 | |
| 282 | status = target_read_stack (memaddr, myaddr, len); |
| 283 | if (status != 0) |
| 284 | memory_error (status, memaddr); |
| 285 | } |
| 286 | |
| 287 | /* Same as target_read_code, but report an error if can't read. */ |
| 288 | |
| 289 | void |
| 290 | read_code (CORE_ADDR memaddr, gdb_byte *myaddr, ssize_t len) |
| 291 | { |
| 292 | int status; |
| 293 | |
| 294 | status = target_read_code (memaddr, myaddr, len); |
| 295 | if (status != 0) |
| 296 | memory_error (status, memaddr); |
| 297 | } |
| 298 | |
| 299 | /* Argument / return result struct for use with |
| 300 | do_captured_read_memory_integer(). MEMADDR and LEN are filled in |
| 301 | by gdb_read_memory_integer(). RESULT is the contents that were |
| 302 | successfully read from MEMADDR of length LEN. */ |
| 303 | |
| 304 | struct captured_read_memory_integer_arguments |
| 305 | { |
| 306 | CORE_ADDR memaddr; |
| 307 | int len; |
| 308 | enum bfd_endian byte_order; |
| 309 | LONGEST result; |
| 310 | }; |
| 311 | |
| 312 | /* Helper function for gdb_read_memory_integer(). DATA must be a |
| 313 | pointer to a captured_read_memory_integer_arguments struct. |
| 314 | Return 1 if successful. Note that the catch_errors() interface |
| 315 | will return 0 if an error occurred while reading memory. This |
| 316 | choice of return code is so that we can distinguish between |
| 317 | success and failure. */ |
| 318 | |
| 319 | static int |
| 320 | do_captured_read_memory_integer (void *data) |
| 321 | { |
| 322 | struct captured_read_memory_integer_arguments *args |
| 323 | = (struct captured_read_memory_integer_arguments*) data; |
| 324 | CORE_ADDR memaddr = args->memaddr; |
| 325 | int len = args->len; |
| 326 | enum bfd_endian byte_order = args->byte_order; |
| 327 | |
| 328 | args->result = read_memory_integer (memaddr, len, byte_order); |
| 329 | |
| 330 | return 1; |
| 331 | } |
| 332 | |
| 333 | /* Read memory at MEMADDR of length LEN and put the contents in |
| 334 | RETURN_VALUE. Return 0 if MEMADDR couldn't be read and non-zero |
| 335 | if successful. */ |
| 336 | |
| 337 | int |
| 338 | safe_read_memory_integer (CORE_ADDR memaddr, int len, |
| 339 | enum bfd_endian byte_order, |
| 340 | LONGEST *return_value) |
| 341 | { |
| 342 | int status; |
| 343 | struct captured_read_memory_integer_arguments args; |
| 344 | |
| 345 | args.memaddr = memaddr; |
| 346 | args.len = len; |
| 347 | args.byte_order = byte_order; |
| 348 | |
| 349 | status = catch_errors (do_captured_read_memory_integer, &args, |
| 350 | "", RETURN_MASK_ALL); |
| 351 | if (status) |
| 352 | *return_value = args.result; |
| 353 | |
| 354 | return status; |
| 355 | } |
| 356 | |
| 357 | LONGEST |
| 358 | read_memory_integer (CORE_ADDR memaddr, int len, |
| 359 | enum bfd_endian byte_order) |
| 360 | { |
| 361 | gdb_byte buf[sizeof (LONGEST)]; |
| 362 | |
| 363 | read_memory (memaddr, buf, len); |
| 364 | return extract_signed_integer (buf, len, byte_order); |
| 365 | } |
| 366 | |
| 367 | ULONGEST |
| 368 | read_memory_unsigned_integer (CORE_ADDR memaddr, int len, |
| 369 | enum bfd_endian byte_order) |
| 370 | { |
| 371 | gdb_byte buf[sizeof (ULONGEST)]; |
| 372 | |
| 373 | read_memory (memaddr, buf, len); |
| 374 | return extract_unsigned_integer (buf, len, byte_order); |
| 375 | } |
| 376 | |
| 377 | LONGEST |
| 378 | read_code_integer (CORE_ADDR memaddr, int len, |
| 379 | enum bfd_endian byte_order) |
| 380 | { |
| 381 | gdb_byte buf[sizeof (LONGEST)]; |
| 382 | |
| 383 | read_code (memaddr, buf, len); |
| 384 | return extract_signed_integer (buf, len, byte_order); |
| 385 | } |
| 386 | |
| 387 | ULONGEST |
| 388 | read_code_unsigned_integer (CORE_ADDR memaddr, int len, |
| 389 | enum bfd_endian byte_order) |
| 390 | { |
| 391 | gdb_byte buf[sizeof (ULONGEST)]; |
| 392 | |
| 393 | read_code (memaddr, buf, len); |
| 394 | return extract_unsigned_integer (buf, len, byte_order); |
| 395 | } |
| 396 | |
| 397 | void |
| 398 | read_memory_string (CORE_ADDR memaddr, char *buffer, int max_len) |
| 399 | { |
| 400 | char *cp; |
| 401 | int i; |
| 402 | int cnt; |
| 403 | |
| 404 | cp = buffer; |
| 405 | while (1) |
| 406 | { |
| 407 | if (cp - buffer >= max_len) |
| 408 | { |
| 409 | buffer[max_len - 1] = '\0'; |
| 410 | break; |
| 411 | } |
| 412 | cnt = max_len - (cp - buffer); |
| 413 | if (cnt > 8) |
| 414 | cnt = 8; |
| 415 | read_memory (memaddr + (int) (cp - buffer), (gdb_byte *) cp, cnt); |
| 416 | for (i = 0; i < cnt && *cp; i++, cp++) |
| 417 | ; /* null body */ |
| 418 | |
| 419 | if (i < cnt && !*cp) |
| 420 | break; |
| 421 | } |
| 422 | } |
| 423 | |
| 424 | CORE_ADDR |
| 425 | read_memory_typed_address (CORE_ADDR addr, struct type *type) |
| 426 | { |
| 427 | gdb_byte *buf = alloca (TYPE_LENGTH (type)); |
| 428 | |
| 429 | read_memory (addr, buf, TYPE_LENGTH (type)); |
| 430 | return extract_typed_address (buf, type); |
| 431 | } |
| 432 | |
| 433 | /* Same as target_write_memory, but report an error if can't |
| 434 | write. */ |
| 435 | void |
| 436 | write_memory (CORE_ADDR memaddr, |
| 437 | const bfd_byte *myaddr, ssize_t len) |
| 438 | { |
| 439 | int status; |
| 440 | |
| 441 | status = target_write_memory (memaddr, myaddr, len); |
| 442 | if (status != 0) |
| 443 | memory_error (status, memaddr); |
| 444 | } |
| 445 | |
| 446 | /* Same as write_memory, but notify 'memory_changed' observers. */ |
| 447 | |
| 448 | void |
| 449 | write_memory_with_notification (CORE_ADDR memaddr, const bfd_byte *myaddr, |
| 450 | ssize_t len) |
| 451 | { |
| 452 | write_memory (memaddr, myaddr, len); |
| 453 | observer_notify_memory_changed (current_inferior (), memaddr, len, myaddr); |
| 454 | } |
| 455 | |
| 456 | /* Store VALUE at ADDR in the inferior as a LEN-byte unsigned |
| 457 | integer. */ |
| 458 | void |
| 459 | write_memory_unsigned_integer (CORE_ADDR addr, int len, |
| 460 | enum bfd_endian byte_order, |
| 461 | ULONGEST value) |
| 462 | { |
| 463 | gdb_byte *buf = alloca (len); |
| 464 | |
| 465 | store_unsigned_integer (buf, len, byte_order, value); |
| 466 | write_memory (addr, buf, len); |
| 467 | } |
| 468 | |
| 469 | /* Store VALUE at ADDR in the inferior as a LEN-byte signed |
| 470 | integer. */ |
| 471 | void |
| 472 | write_memory_signed_integer (CORE_ADDR addr, int len, |
| 473 | enum bfd_endian byte_order, |
| 474 | LONGEST value) |
| 475 | { |
| 476 | gdb_byte *buf = alloca (len); |
| 477 | |
| 478 | store_signed_integer (buf, len, byte_order, value); |
| 479 | write_memory (addr, buf, len); |
| 480 | } |
| 481 | \f |
| 482 | /* The current default bfd target. Points to storage allocated for |
| 483 | gnutarget_string. */ |
| 484 | char *gnutarget; |
| 485 | |
| 486 | /* Same thing, except it is "auto" not NULL for the default case. */ |
| 487 | static char *gnutarget_string; |
| 488 | static void |
| 489 | show_gnutarget_string (struct ui_file *file, int from_tty, |
| 490 | struct cmd_list_element *c, |
| 491 | const char *value) |
| 492 | { |
| 493 | fprintf_filtered (file, |
| 494 | _("The current BFD target is \"%s\".\n"), value); |
| 495 | } |
| 496 | |
| 497 | static void set_gnutarget_command (char *, int, |
| 498 | struct cmd_list_element *); |
| 499 | |
| 500 | static void |
| 501 | set_gnutarget_command (char *ignore, int from_tty, |
| 502 | struct cmd_list_element *c) |
| 503 | { |
| 504 | char *gend = gnutarget_string + strlen (gnutarget_string); |
| 505 | |
| 506 | gend = remove_trailing_whitespace (gnutarget_string, gend); |
| 507 | *gend = '\0'; |
| 508 | |
| 509 | if (strcmp (gnutarget_string, "auto") == 0) |
| 510 | gnutarget = NULL; |
| 511 | else |
| 512 | gnutarget = gnutarget_string; |
| 513 | } |
| 514 | |
| 515 | /* A completion function for "set gnutarget". */ |
| 516 | |
| 517 | static VEC (char_ptr) * |
| 518 | complete_set_gnutarget (struct cmd_list_element *cmd, |
| 519 | const char *text, const char *word) |
| 520 | { |
| 521 | static const char **bfd_targets; |
| 522 | |
| 523 | if (bfd_targets == NULL) |
| 524 | { |
| 525 | int last; |
| 526 | |
| 527 | bfd_targets = bfd_target_list (); |
| 528 | for (last = 0; bfd_targets[last] != NULL; ++last) |
| 529 | ; |
| 530 | |
| 531 | bfd_targets = xrealloc (bfd_targets, (last + 2) * sizeof (const char **)); |
| 532 | bfd_targets[last] = "auto"; |
| 533 | bfd_targets[last + 1] = NULL; |
| 534 | } |
| 535 | |
| 536 | return complete_on_enum (bfd_targets, text, word); |
| 537 | } |
| 538 | |
| 539 | /* Set the gnutarget. */ |
| 540 | void |
| 541 | set_gnutarget (char *newtarget) |
| 542 | { |
| 543 | if (gnutarget_string != NULL) |
| 544 | xfree (gnutarget_string); |
| 545 | gnutarget_string = xstrdup (newtarget); |
| 546 | set_gnutarget_command (NULL, 0, NULL); |
| 547 | } |
| 548 | |
| 549 | void |
| 550 | _initialize_core (void) |
| 551 | { |
| 552 | struct cmd_list_element *c; |
| 553 | |
| 554 | c = add_cmd ("core-file", class_files, core_file_command, _("\ |
| 555 | Use FILE as core dump for examining memory and registers.\n\ |
| 556 | No arg means have no core file. This command has been superseded by the\n\ |
| 557 | `target core' and `detach' commands."), &cmdlist); |
| 558 | set_cmd_completer (c, filename_completer); |
| 559 | |
| 560 | |
| 561 | c = add_setshow_string_noescape_cmd ("gnutarget", class_files, |
| 562 | &gnutarget_string, _("\ |
| 563 | Set the current BFD target."), _("\ |
| 564 | Show the current BFD target."), _("\ |
| 565 | Use `set gnutarget auto' to specify automatic detection."), |
| 566 | set_gnutarget_command, |
| 567 | show_gnutarget_string, |
| 568 | &setlist, &showlist); |
| 569 | set_cmd_completer (c, complete_set_gnutarget); |
| 570 | |
| 571 | add_alias_cmd ("g", "gnutarget", class_files, 1, &setlist); |
| 572 | |
| 573 | if (getenv ("GNUTARGET")) |
| 574 | set_gnutarget (getenv ("GNUTARGET")); |
| 575 | else |
| 576 | set_gnutarget ("auto"); |
| 577 | } |