| 1 | /* Core dump and executable file functions above target vector, for GDB. |
| 2 | |
| 3 | Copyright (C) 1986-1987, 1989, 1991-1994, 1996-2001, 2003, 2006-2012 |
| 4 | Free Software Foundation, Inc. |
| 5 | |
| 6 | This file is part of GDB. |
| 7 | |
| 8 | This program is free software; you can redistribute it and/or modify |
| 9 | it under the terms of the GNU General Public License as published by |
| 10 | the Free Software Foundation; either version 3 of the License, or |
| 11 | (at your option) any later version. |
| 12 | |
| 13 | This program is distributed in the hope that it will be useful, |
| 14 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | GNU General Public License for more details. |
| 17 | |
| 18 | You should have received a copy of the GNU General Public License |
| 19 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 20 | |
| 21 | #include "defs.h" |
| 22 | #include "gdb_string.h" |
| 23 | #include <errno.h> |
| 24 | #include <signal.h> |
| 25 | #include <fcntl.h> |
| 26 | #include "inferior.h" |
| 27 | #include "symtab.h" |
| 28 | #include "command.h" |
| 29 | #include "gdbcmd.h" |
| 30 | #include "bfd.h" |
| 31 | #include "target.h" |
| 32 | #include "gdbcore.h" |
| 33 | #include "dis-asm.h" |
| 34 | #include "gdb_stat.h" |
| 35 | #include "completer.h" |
| 36 | #include "exceptions.h" |
| 37 | #include "observer.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_bfd) |
| 186 | return bfd_get_filename (exec_bfd); |
| 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 | /* Report a memory error by throwing a MEMORY_ERROR error. */ |
| 197 | |
| 198 | void |
| 199 | memory_error (int status, CORE_ADDR memaddr) |
| 200 | { |
| 201 | if (status == EIO) |
| 202 | /* Actually, address between memaddr and memaddr + len was out of |
| 203 | bounds. */ |
| 204 | throw_error (MEMORY_ERROR, |
| 205 | _("Cannot access memory at address %s"), |
| 206 | paddress (target_gdbarch (), memaddr)); |
| 207 | else |
| 208 | throw_error (MEMORY_ERROR, |
| 209 | _("Error accessing memory address %s: %s."), |
| 210 | paddress (target_gdbarch (), memaddr), |
| 211 | safe_strerror (status)); |
| 212 | } |
| 213 | |
| 214 | /* Same as target_read_memory, but report an error if can't read. */ |
| 215 | |
| 216 | void |
| 217 | read_memory (CORE_ADDR memaddr, gdb_byte *myaddr, ssize_t len) |
| 218 | { |
| 219 | int status; |
| 220 | |
| 221 | status = target_read_memory (memaddr, myaddr, len); |
| 222 | if (status != 0) |
| 223 | memory_error (status, memaddr); |
| 224 | } |
| 225 | |
| 226 | /* Same as target_read_stack, but report an error if can't read. */ |
| 227 | |
| 228 | void |
| 229 | read_stack (CORE_ADDR memaddr, gdb_byte *myaddr, ssize_t len) |
| 230 | { |
| 231 | int status; |
| 232 | |
| 233 | status = target_read_stack (memaddr, myaddr, len); |
| 234 | if (status != 0) |
| 235 | memory_error (status, memaddr); |
| 236 | } |
| 237 | |
| 238 | /* Argument / return result struct for use with |
| 239 | do_captured_read_memory_integer(). MEMADDR and LEN are filled in |
| 240 | by gdb_read_memory_integer(). RESULT is the contents that were |
| 241 | successfully read from MEMADDR of length LEN. */ |
| 242 | |
| 243 | struct captured_read_memory_integer_arguments |
| 244 | { |
| 245 | CORE_ADDR memaddr; |
| 246 | int len; |
| 247 | enum bfd_endian byte_order; |
| 248 | LONGEST result; |
| 249 | }; |
| 250 | |
| 251 | /* Helper function for gdb_read_memory_integer(). DATA must be a |
| 252 | pointer to a captured_read_memory_integer_arguments struct. |
| 253 | Return 1 if successful. Note that the catch_errors() interface |
| 254 | will return 0 if an error occurred while reading memory. This |
| 255 | choice of return code is so that we can distinguish between |
| 256 | success and failure. */ |
| 257 | |
| 258 | static int |
| 259 | do_captured_read_memory_integer (void *data) |
| 260 | { |
| 261 | struct captured_read_memory_integer_arguments *args |
| 262 | = (struct captured_read_memory_integer_arguments*) data; |
| 263 | CORE_ADDR memaddr = args->memaddr; |
| 264 | int len = args->len; |
| 265 | enum bfd_endian byte_order = args->byte_order; |
| 266 | |
| 267 | args->result = read_memory_integer (memaddr, len, byte_order); |
| 268 | |
| 269 | return 1; |
| 270 | } |
| 271 | |
| 272 | /* Read memory at MEMADDR of length LEN and put the contents in |
| 273 | RETURN_VALUE. Return 0 if MEMADDR couldn't be read and non-zero |
| 274 | if successful. */ |
| 275 | |
| 276 | int |
| 277 | safe_read_memory_integer (CORE_ADDR memaddr, int len, |
| 278 | enum bfd_endian byte_order, |
| 279 | LONGEST *return_value) |
| 280 | { |
| 281 | int status; |
| 282 | struct captured_read_memory_integer_arguments args; |
| 283 | |
| 284 | args.memaddr = memaddr; |
| 285 | args.len = len; |
| 286 | args.byte_order = byte_order; |
| 287 | |
| 288 | status = catch_errors (do_captured_read_memory_integer, &args, |
| 289 | "", RETURN_MASK_ALL); |
| 290 | if (status) |
| 291 | *return_value = args.result; |
| 292 | |
| 293 | return status; |
| 294 | } |
| 295 | |
| 296 | LONGEST |
| 297 | read_memory_integer (CORE_ADDR memaddr, int len, |
| 298 | enum bfd_endian byte_order) |
| 299 | { |
| 300 | gdb_byte buf[sizeof (LONGEST)]; |
| 301 | |
| 302 | read_memory (memaddr, buf, len); |
| 303 | return extract_signed_integer (buf, len, byte_order); |
| 304 | } |
| 305 | |
| 306 | ULONGEST |
| 307 | read_memory_unsigned_integer (CORE_ADDR memaddr, int len, |
| 308 | enum bfd_endian byte_order) |
| 309 | { |
| 310 | gdb_byte buf[sizeof (ULONGEST)]; |
| 311 | |
| 312 | read_memory (memaddr, buf, len); |
| 313 | return extract_unsigned_integer (buf, len, byte_order); |
| 314 | } |
| 315 | |
| 316 | void |
| 317 | read_memory_string (CORE_ADDR memaddr, char *buffer, int max_len) |
| 318 | { |
| 319 | char *cp; |
| 320 | int i; |
| 321 | int cnt; |
| 322 | |
| 323 | cp = buffer; |
| 324 | while (1) |
| 325 | { |
| 326 | if (cp - buffer >= max_len) |
| 327 | { |
| 328 | buffer[max_len - 1] = '\0'; |
| 329 | break; |
| 330 | } |
| 331 | cnt = max_len - (cp - buffer); |
| 332 | if (cnt > 8) |
| 333 | cnt = 8; |
| 334 | read_memory (memaddr + (int) (cp - buffer), cp, cnt); |
| 335 | for (i = 0; i < cnt && *cp; i++, cp++) |
| 336 | ; /* null body */ |
| 337 | |
| 338 | if (i < cnt && !*cp) |
| 339 | break; |
| 340 | } |
| 341 | } |
| 342 | |
| 343 | CORE_ADDR |
| 344 | read_memory_typed_address (CORE_ADDR addr, struct type *type) |
| 345 | { |
| 346 | gdb_byte *buf = alloca (TYPE_LENGTH (type)); |
| 347 | |
| 348 | read_memory (addr, buf, TYPE_LENGTH (type)); |
| 349 | return extract_typed_address (buf, type); |
| 350 | } |
| 351 | |
| 352 | /* Same as target_write_memory, but report an error if can't |
| 353 | write. */ |
| 354 | void |
| 355 | write_memory (CORE_ADDR memaddr, |
| 356 | const bfd_byte *myaddr, ssize_t len) |
| 357 | { |
| 358 | int status; |
| 359 | |
| 360 | status = target_write_memory (memaddr, myaddr, len); |
| 361 | if (status != 0) |
| 362 | memory_error (status, memaddr); |
| 363 | } |
| 364 | |
| 365 | /* Same as write_memory, but notify 'memory_changed' observers. */ |
| 366 | |
| 367 | void |
| 368 | write_memory_with_notification (CORE_ADDR memaddr, const bfd_byte *myaddr, |
| 369 | ssize_t len) |
| 370 | { |
| 371 | write_memory (memaddr, myaddr, len); |
| 372 | observer_notify_memory_changed (current_inferior (), memaddr, len, myaddr); |
| 373 | } |
| 374 | |
| 375 | /* Store VALUE at ADDR in the inferior as a LEN-byte unsigned |
| 376 | integer. */ |
| 377 | void |
| 378 | write_memory_unsigned_integer (CORE_ADDR addr, int len, |
| 379 | enum bfd_endian byte_order, |
| 380 | ULONGEST value) |
| 381 | { |
| 382 | gdb_byte *buf = alloca (len); |
| 383 | |
| 384 | store_unsigned_integer (buf, len, byte_order, value); |
| 385 | write_memory (addr, buf, len); |
| 386 | } |
| 387 | |
| 388 | /* Store VALUE at ADDR in the inferior as a LEN-byte signed |
| 389 | integer. */ |
| 390 | void |
| 391 | write_memory_signed_integer (CORE_ADDR addr, int len, |
| 392 | enum bfd_endian byte_order, |
| 393 | LONGEST value) |
| 394 | { |
| 395 | gdb_byte *buf = alloca (len); |
| 396 | |
| 397 | store_signed_integer (buf, len, byte_order, value); |
| 398 | write_memory (addr, buf, len); |
| 399 | } |
| 400 | \f |
| 401 | /* The current default bfd target. Points to storage allocated for |
| 402 | gnutarget_string. */ |
| 403 | char *gnutarget; |
| 404 | |
| 405 | /* Same thing, except it is "auto" not NULL for the default case. */ |
| 406 | static char *gnutarget_string; |
| 407 | static void |
| 408 | show_gnutarget_string (struct ui_file *file, int from_tty, |
| 409 | struct cmd_list_element *c, |
| 410 | const char *value) |
| 411 | { |
| 412 | fprintf_filtered (file, |
| 413 | _("The current BFD target is \"%s\".\n"), value); |
| 414 | } |
| 415 | |
| 416 | static void set_gnutarget_command (char *, int, |
| 417 | struct cmd_list_element *); |
| 418 | |
| 419 | static void |
| 420 | set_gnutarget_command (char *ignore, int from_tty, |
| 421 | struct cmd_list_element *c) |
| 422 | { |
| 423 | if (strcmp (gnutarget_string, "auto") == 0) |
| 424 | gnutarget = NULL; |
| 425 | else |
| 426 | gnutarget = gnutarget_string; |
| 427 | } |
| 428 | |
| 429 | /* Set the gnutarget. */ |
| 430 | void |
| 431 | set_gnutarget (char *newtarget) |
| 432 | { |
| 433 | if (gnutarget_string != NULL) |
| 434 | xfree (gnutarget_string); |
| 435 | gnutarget_string = xstrdup (newtarget); |
| 436 | set_gnutarget_command (NULL, 0, NULL); |
| 437 | } |
| 438 | |
| 439 | void |
| 440 | _initialize_core (void) |
| 441 | { |
| 442 | struct cmd_list_element *c; |
| 443 | |
| 444 | c = add_cmd ("core-file", class_files, core_file_command, _("\ |
| 445 | Use FILE as core dump for examining memory and registers.\n\ |
| 446 | No arg means have no core file. This command has been superseded by the\n\ |
| 447 | `target core' and `detach' commands."), &cmdlist); |
| 448 | set_cmd_completer (c, filename_completer); |
| 449 | |
| 450 | |
| 451 | add_setshow_string_noescape_cmd ("gnutarget", class_files, |
| 452 | &gnutarget_string, _("\ |
| 453 | Set the current BFD target."), _("\ |
| 454 | Show the current BFD target."), _("\ |
| 455 | Use `set gnutarget auto' to specify automatic detection."), |
| 456 | set_gnutarget_command, |
| 457 | show_gnutarget_string, |
| 458 | &setlist, &showlist); |
| 459 | |
| 460 | if (getenv ("GNUTARGET")) |
| 461 | set_gnutarget (getenv ("GNUTARGET")); |
| 462 | else |
| 463 | set_gnutarget ("auto"); |
| 464 | } |