1 /* Core dump and executable file functions above target vector, for GDB. 2 3 Copyright (C) 1986, 1987, 1989, 1991, 1992, 1993, 1994, 1996, 1997, 1998, 4 1999, 2000, 2001, 2003, 2006, 2007, 2008, 2009, 2010 5 Free Software Foundation, Inc. 6 7 This file is part of GDB. 8 9 This program is free software; you can redistribute it and/or modify 10 it under the terms of the GNU General Public License as published by 11 the Free Software Foundation; either version 3 of the License, or 12 (at your option) any later version. 13 14 This program is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License for more details. 18 19 You should have received a copy of the GNU General Public License 20 along with this program. If not, see <http://www.gnu.org/licenses/>. */ 21 22 #include "defs.h" 23 #include "gdb_string.h" 24 #include <errno.h> 25 #include <signal.h> 26 #include <fcntl.h> 27 #include "inferior.h" 28 #include "symtab.h" 29 #include "command.h" 30 #include "gdbcmd.h" 31 #include "bfd.h" 32 #include "target.h" 33 #include "gdbcore.h" 34 #include "dis-asm.h" 35 #include "gdb_stat.h" 36 #include "completer.h" 37 #include "exceptions.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 hooks */ 57 static int exec_file_hook_count = 0; /* size of array */ 58 59 /* Binary file diddling handle for the core file. */ 60 61 bfd *core_bfd = NULL; 62 63 64 /* Backward compatability with old way of specifying core files. */ 65 66 void 67 core_file_command (char *filename, int from_tty) 68 { 69 struct target_ops *t; 70 71 dont_repeat (); /* Either way, seems bogus. */ 72 73 t = find_core_target (); 74 if (t == NULL) 75 error (_("GDB can't read core files on this machine.")); 76 77 if (!filename) 78 (t->to_detach) (t, filename, from_tty); 79 else 80 (t->to_open) (filename, from_tty); 81 } 82 83 84 /* If there are two or more functions that wish to hook into 85 exec_file_command, this function will call all of the hook 86 functions. */ 87 88 static void 89 call_extra_exec_file_hooks (char *filename) 90 { 91 int i; 92 93 for (i = 0; i < exec_file_hook_count; i++) 94 (*exec_file_extra_hooks[i]) (filename); 95 } 96 97 /* Call this to specify the hook for exec_file_command to call back. 98 This is called from the x-window display code. */ 99 100 void 101 specify_exec_file_hook (void (*hook) (char *)) 102 { 103 hook_type *new_array; 104 105 if (deprecated_exec_file_display_hook != NULL) 106 { 107 /* There's already a hook installed. Arrange to have both it 108 * and the subsequent hooks called. */ 109 if (exec_file_hook_count == 0) 110 { 111 /* If this is the first extra hook, initialize the hook array. */ 112 exec_file_extra_hooks = (hook_type *) xmalloc (sizeof (hook_type)); 113 exec_file_extra_hooks[0] = deprecated_exec_file_display_hook; 114 deprecated_exec_file_display_hook = call_extra_exec_file_hooks; 115 exec_file_hook_count = 1; 116 } 117 118 /* Grow the hook array by one and add the new hook to the end. 119 Yes, it's inefficient to grow it by one each time but since 120 this is hardly ever called it's not a big deal. */ 121 exec_file_hook_count++; 122 new_array = 123 (hook_type *) xrealloc (exec_file_extra_hooks, 124 exec_file_hook_count * sizeof (hook_type)); 125 exec_file_extra_hooks = new_array; 126 exec_file_extra_hooks[exec_file_hook_count - 1] = hook; 127 } 128 else 129 deprecated_exec_file_display_hook = hook; 130 } 131 132 /* The exec file must be closed before running an inferior. 133 If it is needed again after the inferior dies, it must 134 be reopened. */ 135 136 void 137 close_exec_file (void) 138 { 139 #if 0 /* FIXME */ 140 if (exec_bfd) 141 bfd_tempclose (exec_bfd); 142 #endif 143 } 144 145 void 146 reopen_exec_file (void) 147 { 148 #if 0 /* FIXME */ 149 if (exec_bfd) 150 bfd_reopen (exec_bfd); 151 #else 152 char *filename; 153 int res; 154 struct stat st; 155 struct cleanup *cleanups; 156 157 /* Don't do anything if there isn't an exec file. */ 158 if (exec_bfd == NULL) 159 return; 160 161 /* If the timestamp of the exec file has changed, reopen it. */ 162 filename = xstrdup (bfd_get_filename (exec_bfd)); 163 cleanups = make_cleanup (xfree, filename); 164 res = stat (filename, &st); 165 166 if (exec_bfd_mtime && exec_bfd_mtime != st.st_mtime) 167 exec_file_attach (filename, 0); 168 else 169 /* If we accessed the file since last opening it, close it now; 170 this stops GDB from holding the executable open after it 171 exits. */ 172 bfd_cache_close_all (); 173 174 do_cleanups (cleanups); 175 #endif 176 } 177 178 /* If we have both a core file and an exec file, 179 print a warning if they don't go together. */ 180 181 void 182 validate_files (void) 183 { 184 if (exec_bfd && core_bfd) 185 { 186 if (!core_file_matches_executable_p (core_bfd, exec_bfd)) 187 warning (_("core file may not match specified executable file.")); 188 else if (bfd_get_mtime (exec_bfd) > bfd_get_mtime (core_bfd)) 189 warning (_("exec file is newer than core file.")); 190 } 191 } 192 193 /* Return the name of the executable file as a string. 194 ERR nonzero means get error if there is none specified; 195 otherwise return 0 in that case. */ 196 197 char * 198 get_exec_file (int err) 199 { 200 if (exec_bfd) 201 return bfd_get_filename (exec_bfd); 202 if (!err) 203 return NULL; 204 205 error (_("No executable file specified.\n\ 206 Use the \"file\" or \"exec-file\" command.")); 207 return NULL; 208 } 209 210 211 /* Report a memory error by throwing a MEMORY_ERROR error. */ 212 213 void 214 memory_error (int status, CORE_ADDR memaddr) 215 { 216 if (status == EIO) 217 /* Actually, address between memaddr and memaddr + len was out of 218 bounds. */ 219 throw_error (MEMORY_ERROR, 220 _("Cannot access memory at address %s"), 221 paddress (target_gdbarch, memaddr)); 222 else 223 throw_error (MEMORY_ERROR, 224 _("Error accessing memory address %s: %s."), 225 paddress (target_gdbarch, memaddr), 226 safe_strerror (status)); 227 } 228 229 /* Same as target_read_memory, but report an error if can't read. */ 230 231 void 232 read_memory (CORE_ADDR memaddr, gdb_byte *myaddr, int len) 233 { 234 int status; 235 236 status = target_read_memory (memaddr, myaddr, len); 237 if (status != 0) 238 memory_error (status, memaddr); 239 } 240 241 /* Same as target_read_stack, but report an error if can't read. */ 242 243 void 244 read_stack (CORE_ADDR memaddr, gdb_byte *myaddr, int len) 245 { 246 int status; 247 248 status = target_read_stack (memaddr, myaddr, len); 249 if (status != 0) 250 memory_error (status, memaddr); 251 } 252 253 /* Argument / return result struct for use with 254 do_captured_read_memory_integer(). MEMADDR and LEN are filled in 255 by gdb_read_memory_integer(). RESULT is the contents that were 256 successfully read from MEMADDR of length LEN. */ 257 258 struct captured_read_memory_integer_arguments 259 { 260 CORE_ADDR memaddr; 261 int len; 262 enum bfd_endian byte_order; 263 LONGEST result; 264 }; 265 266 /* Helper function for gdb_read_memory_integer(). DATA must be a 267 pointer to a captured_read_memory_integer_arguments struct. 268 Return 1 if successful. Note that the catch_errors() interface 269 will return 0 if an error occurred while reading memory. This 270 choice of return code is so that we can distinguish between 271 success and failure. */ 272 273 static int 274 do_captured_read_memory_integer (void *data) 275 { 276 struct captured_read_memory_integer_arguments *args = (struct captured_read_memory_integer_arguments*) data; 277 CORE_ADDR memaddr = args->memaddr; 278 int len = args->len; 279 enum bfd_endian byte_order = args->byte_order; 280 281 args->result = read_memory_integer (memaddr, len, byte_order); 282 283 return 1; 284 } 285 286 /* Read memory at MEMADDR of length LEN and put the contents in 287 RETURN_VALUE. Return 0 if MEMADDR couldn't be read and non-zero 288 if successful. */ 289 290 int 291 safe_read_memory_integer (CORE_ADDR memaddr, int len, 292 enum bfd_endian byte_order, 293 LONGEST *return_value) 294 { 295 int status; 296 struct captured_read_memory_integer_arguments args; 297 298 args.memaddr = memaddr; 299 args.len = len; 300 args.byte_order = byte_order; 301 302 status = catch_errors (do_captured_read_memory_integer, &args, 303 "", RETURN_MASK_ALL); 304 if (status) 305 *return_value = args.result; 306 307 return status; 308 } 309 310 LONGEST 311 read_memory_integer (CORE_ADDR memaddr, int len, enum bfd_endian byte_order) 312 { 313 gdb_byte buf[sizeof (LONGEST)]; 314 315 read_memory (memaddr, buf, len); 316 return extract_signed_integer (buf, len, byte_order); 317 } 318 319 ULONGEST 320 read_memory_unsigned_integer (CORE_ADDR memaddr, int len, enum bfd_endian byte_order) 321 { 322 gdb_byte buf[sizeof (ULONGEST)]; 323 324 read_memory (memaddr, buf, len); 325 return extract_unsigned_integer (buf, len, byte_order); 326 } 327 328 void 329 read_memory_string (CORE_ADDR memaddr, char *buffer, int max_len) 330 { 331 char *cp; 332 int i; 333 int cnt; 334 335 cp = buffer; 336 while (1) 337 { 338 if (cp - buffer >= max_len) 339 { 340 buffer[max_len - 1] = '\0'; 341 break; 342 } 343 cnt = max_len - (cp - buffer); 344 if (cnt > 8) 345 cnt = 8; 346 read_memory (memaddr + (int) (cp - buffer), cp, cnt); 347 for (i = 0; i < cnt && *cp; i++, cp++) 348 ; /* null body */ 349 350 if (i < cnt && !*cp) 351 break; 352 } 353 } 354 355 CORE_ADDR 356 read_memory_typed_address (CORE_ADDR addr, struct type *type) 357 { 358 gdb_byte *buf = alloca (TYPE_LENGTH (type)); 359 360 read_memory (addr, buf, TYPE_LENGTH (type)); 361 return extract_typed_address (buf, type); 362 } 363 364 /* Same as target_write_memory, but report an error if can't write. */ 365 void 366 write_memory (CORE_ADDR memaddr, const bfd_byte *myaddr, int len) 367 { 368 int status; 369 370 status = target_write_memory (memaddr, myaddr, len); 371 if (status != 0) 372 memory_error (status, memaddr); 373 } 374 375 /* Store VALUE at ADDR in the inferior as a LEN-byte unsigned integer. */ 376 void 377 write_memory_unsigned_integer (CORE_ADDR addr, int len, 378 enum bfd_endian byte_order, 379 ULONGEST value) 380 { 381 gdb_byte *buf = alloca (len); 382 383 store_unsigned_integer (buf, len, byte_order, value); 384 write_memory (addr, buf, len); 385 } 386 387 /* Store VALUE at ADDR in the inferior as a LEN-byte signed integer. */ 388 void 389 write_memory_signed_integer (CORE_ADDR addr, int len, 390 enum bfd_endian byte_order, 391 LONGEST value) 392 { 393 gdb_byte *buf = alloca (len); 394 395 store_signed_integer (buf, len, byte_order, value); 396 write_memory (addr, buf, len); 397 } 398 399 /* The current default bfd target. Points to storage allocated for 400 gnutarget_string. */ 401 char *gnutarget; 402 403 /* Same thing, except it is "auto" not NULL for the default case. */ 404 static char *gnutarget_string; 405 static void 406 show_gnutarget_string (struct ui_file *file, int from_tty, 407 struct cmd_list_element *c, const char *value) 408 { 409 fprintf_filtered (file, _("The current BFD target is \"%s\".\n"), value); 410 } 411 412 static void set_gnutarget_command (char *, int, struct cmd_list_element *); 413 414 static void 415 set_gnutarget_command (char *ignore, int from_tty, struct cmd_list_element *c) 416 { 417 if (strcmp (gnutarget_string, "auto") == 0) 418 gnutarget = NULL; 419 else 420 gnutarget = gnutarget_string; 421 } 422 423 /* Set the gnutarget. */ 424 void 425 set_gnutarget (char *newtarget) 426 { 427 if (gnutarget_string != NULL) 428 xfree (gnutarget_string); 429 gnutarget_string = xstrdup (newtarget); 430 set_gnutarget_command (NULL, 0, NULL); 431 } 432 433 void 434 _initialize_core (void) 435 { 436 struct cmd_list_element *c; 437 438 c = add_cmd ("core-file", class_files, core_file_command, _("\ 439 Use FILE as core dump for examining memory and registers.\n\ 440 No arg means have no core file. This command has been superseded by the\n\ 441 `target core' and `detach' commands."), &cmdlist); 442 set_cmd_completer (c, filename_completer); 443 444 445 add_setshow_string_noescape_cmd ("gnutarget", class_files, 446 &gnutarget_string, _("\ 447 Set the current BFD target."), _("\ 448 Show the current BFD target."), _("\ 449 Use `set gnutarget auto' to specify automatic detection."), 450 set_gnutarget_command, 451 show_gnutarget_string, 452 &setlist, &showlist); 453 454 if (getenv ("GNUTARGET")) 455 set_gnutarget (getenv ("GNUTARGET")); 456 else 457 set_gnutarget ("auto"); 458 } 459