| 1 | /* Core dump and executable file functions below target vector, for GDB. |
| 2 | |
| 3 | Copyright 1986, 1987, 1989, 1991, 1992, 1993, 1994, 1995, 1996, |
| 4 | 1997, 1998, 1999, 2000, 2001, 2003 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 2 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, write to the Free Software |
| 20 | Foundation, Inc., 59 Temple Place - Suite 330, |
| 21 | Boston, MA 02111-1307, USA. */ |
| 22 | |
| 23 | #include "defs.h" |
| 24 | #include "gdb_string.h" |
| 25 | #include <errno.h> |
| 26 | #include <signal.h> |
| 27 | #include <fcntl.h> |
| 28 | #ifdef HAVE_SYS_FILE_H |
| 29 | #include <sys/file.h> /* needed for F_OK and friends */ |
| 30 | #endif |
| 31 | #include "frame.h" /* required by inferior.h */ |
| 32 | #include "inferior.h" |
| 33 | #include "symtab.h" |
| 34 | #include "command.h" |
| 35 | #include "bfd.h" |
| 36 | #include "target.h" |
| 37 | #include "gdbcore.h" |
| 38 | #include "gdbthread.h" |
| 39 | #include "regcache.h" |
| 40 | #include "symfile.h" |
| 41 | #include "exec.h" |
| 42 | #include <readline/readline.h> |
| 43 | |
| 44 | #ifndef O_BINARY |
| 45 | #define O_BINARY 0 |
| 46 | #endif |
| 47 | |
| 48 | /* List of all available core_fns. On gdb startup, each core file register |
| 49 | reader calls add_core_fns() to register information on each core format it |
| 50 | is prepared to read. */ |
| 51 | |
| 52 | static struct core_fns *core_file_fns = NULL; |
| 53 | |
| 54 | /* The core_fns for a core file handler that is prepared to read the core |
| 55 | file currently open on core_bfd. */ |
| 56 | |
| 57 | static struct core_fns *core_vec = NULL; |
| 58 | |
| 59 | static void core_files_info (struct target_ops *); |
| 60 | |
| 61 | #ifdef SOLIB_ADD |
| 62 | static int solib_add_stub (void *); |
| 63 | #endif |
| 64 | |
| 65 | static struct core_fns *sniff_core_bfd (bfd *); |
| 66 | |
| 67 | static int gdb_check_format (bfd *); |
| 68 | |
| 69 | static void core_open (char *, int); |
| 70 | |
| 71 | static void core_detach (char *, int); |
| 72 | |
| 73 | static void core_close (int); |
| 74 | |
| 75 | static void core_close_cleanup (void *ignore); |
| 76 | |
| 77 | static void get_core_registers (int); |
| 78 | |
| 79 | static void add_to_thread_list (bfd *, asection *, void *); |
| 80 | |
| 81 | static int ignore (CORE_ADDR, char *); |
| 82 | |
| 83 | static int core_file_thread_alive (ptid_t tid); |
| 84 | |
| 85 | static void init_core_ops (void); |
| 86 | |
| 87 | void _initialize_corelow (void); |
| 88 | |
| 89 | struct target_ops core_ops; |
| 90 | |
| 91 | /* Link a new core_fns into the global core_file_fns list. Called on gdb |
| 92 | startup by the _initialize routine in each core file register reader, to |
| 93 | register information about each format the the reader is prepared to |
| 94 | handle. */ |
| 95 | |
| 96 | void |
| 97 | add_core_fns (struct core_fns *cf) |
| 98 | { |
| 99 | cf->next = core_file_fns; |
| 100 | core_file_fns = cf; |
| 101 | } |
| 102 | |
| 103 | /* The default function that core file handlers can use to examine a |
| 104 | core file BFD and decide whether or not to accept the job of |
| 105 | reading the core file. */ |
| 106 | |
| 107 | int |
| 108 | default_core_sniffer (struct core_fns *our_fns, bfd *abfd) |
| 109 | { |
| 110 | int result; |
| 111 | |
| 112 | result = (bfd_get_flavour (abfd) == our_fns -> core_flavour); |
| 113 | return (result); |
| 114 | } |
| 115 | |
| 116 | /* Walk through the list of core functions to find a set that can |
| 117 | handle the core file open on ABFD. Default to the first one in the |
| 118 | list if nothing matches. Returns pointer to set that is |
| 119 | selected. */ |
| 120 | |
| 121 | static struct core_fns * |
| 122 | sniff_core_bfd (bfd *abfd) |
| 123 | { |
| 124 | struct core_fns *cf; |
| 125 | struct core_fns *yummy = NULL; |
| 126 | int matches = 0;; |
| 127 | |
| 128 | for (cf = core_file_fns; cf != NULL; cf = cf->next) |
| 129 | { |
| 130 | if (cf->core_sniffer (cf, abfd)) |
| 131 | { |
| 132 | yummy = cf; |
| 133 | matches++; |
| 134 | } |
| 135 | } |
| 136 | if (matches > 1) |
| 137 | { |
| 138 | warning ("\"%s\": ambiguous core format, %d handlers match", |
| 139 | bfd_get_filename (abfd), matches); |
| 140 | } |
| 141 | else if (matches == 0) |
| 142 | { |
| 143 | warning ("\"%s\": no core file handler recognizes format, using default", |
| 144 | bfd_get_filename (abfd)); |
| 145 | } |
| 146 | if (yummy == NULL) |
| 147 | { |
| 148 | yummy = core_file_fns; |
| 149 | } |
| 150 | return (yummy); |
| 151 | } |
| 152 | |
| 153 | /* The default is to reject every core file format we see. Either |
| 154 | BFD has to recognize it, or we have to provide a function in the |
| 155 | core file handler that recognizes it. */ |
| 156 | |
| 157 | int |
| 158 | default_check_format (bfd *abfd) |
| 159 | { |
| 160 | return (0); |
| 161 | } |
| 162 | |
| 163 | /* Attempt to recognize core file formats that BFD rejects. */ |
| 164 | |
| 165 | static int |
| 166 | gdb_check_format (bfd *abfd) |
| 167 | { |
| 168 | struct core_fns *cf; |
| 169 | |
| 170 | for (cf = core_file_fns; cf != NULL; cf = cf->next) |
| 171 | { |
| 172 | if (cf->check_format (abfd)) |
| 173 | { |
| 174 | return (1); |
| 175 | } |
| 176 | } |
| 177 | return (0); |
| 178 | } |
| 179 | |
| 180 | /* Discard all vestiges of any previous core file and mark data and stack |
| 181 | spaces as empty. */ |
| 182 | |
| 183 | static void |
| 184 | core_close (int quitting) |
| 185 | { |
| 186 | char *name; |
| 187 | |
| 188 | if (core_bfd) |
| 189 | { |
| 190 | inferior_ptid = null_ptid; /* Avoid confusion from thread stuff */ |
| 191 | |
| 192 | /* Clear out solib state while the bfd is still open. See |
| 193 | comments in clear_solib in solib.c. */ |
| 194 | #ifdef CLEAR_SOLIB |
| 195 | CLEAR_SOLIB (); |
| 196 | #endif |
| 197 | |
| 198 | name = bfd_get_filename (core_bfd); |
| 199 | if (!bfd_close (core_bfd)) |
| 200 | warning ("cannot close \"%s\": %s", |
| 201 | name, bfd_errmsg (bfd_get_error ())); |
| 202 | xfree (name); |
| 203 | core_bfd = NULL; |
| 204 | if (core_ops.to_sections) |
| 205 | { |
| 206 | xfree (core_ops.to_sections); |
| 207 | core_ops.to_sections = NULL; |
| 208 | core_ops.to_sections_end = NULL; |
| 209 | } |
| 210 | } |
| 211 | core_vec = NULL; |
| 212 | } |
| 213 | |
| 214 | static void |
| 215 | core_close_cleanup (void *ignore) |
| 216 | { |
| 217 | core_close (0/*ignored*/); |
| 218 | } |
| 219 | |
| 220 | #ifdef SOLIB_ADD |
| 221 | /* Stub function for catch_errors around shared library hacking. FROM_TTYP |
| 222 | is really an int * which points to from_tty. */ |
| 223 | |
| 224 | static int |
| 225 | solib_add_stub (void *from_ttyp) |
| 226 | { |
| 227 | SOLIB_ADD (NULL, *(int *) from_ttyp, ¤t_target, auto_solib_add); |
| 228 | re_enable_breakpoints_in_shlibs (); |
| 229 | return 0; |
| 230 | } |
| 231 | #endif /* SOLIB_ADD */ |
| 232 | |
| 233 | /* Look for sections whose names start with `.reg/' so that we can extract the |
| 234 | list of threads in a core file. */ |
| 235 | |
| 236 | static void |
| 237 | add_to_thread_list (bfd *abfd, asection *asect, void *reg_sect_arg) |
| 238 | { |
| 239 | int thread_id; |
| 240 | asection *reg_sect = (asection *) reg_sect_arg; |
| 241 | |
| 242 | if (strncmp (bfd_section_name (abfd, asect), ".reg/", 5) != 0) |
| 243 | return; |
| 244 | |
| 245 | thread_id = atoi (bfd_section_name (abfd, asect) + 5); |
| 246 | |
| 247 | add_thread (pid_to_ptid (thread_id)); |
| 248 | |
| 249 | /* Warning, Will Robinson, looking at BFD private data! */ |
| 250 | |
| 251 | if (reg_sect != NULL |
| 252 | && asect->filepos == reg_sect->filepos) /* Did we find .reg? */ |
| 253 | inferior_ptid = pid_to_ptid (thread_id); /* Yes, make it current */ |
| 254 | } |
| 255 | |
| 256 | /* This routine opens and sets up the core file bfd. */ |
| 257 | |
| 258 | static void |
| 259 | core_open (char *filename, int from_tty) |
| 260 | { |
| 261 | const char *p; |
| 262 | int siggy; |
| 263 | struct cleanup *old_chain; |
| 264 | char *temp; |
| 265 | bfd *temp_bfd; |
| 266 | int ontop; |
| 267 | int scratch_chan; |
| 268 | |
| 269 | target_preopen (from_tty); |
| 270 | if (!filename) |
| 271 | { |
| 272 | error (core_bfd ? |
| 273 | "No core file specified. (Use `detach' to stop debugging a core file.)" |
| 274 | : "No core file specified."); |
| 275 | } |
| 276 | |
| 277 | filename = tilde_expand (filename); |
| 278 | if (filename[0] != '/') |
| 279 | { |
| 280 | temp = concat (current_directory, "/", filename, NULL); |
| 281 | xfree (filename); |
| 282 | filename = temp; |
| 283 | } |
| 284 | |
| 285 | old_chain = make_cleanup (xfree, filename); |
| 286 | |
| 287 | scratch_chan = open (filename, O_BINARY | ( write_files ? O_RDWR : O_RDONLY ), 0); |
| 288 | if (scratch_chan < 0) |
| 289 | perror_with_name (filename); |
| 290 | |
| 291 | temp_bfd = bfd_fdopenr (filename, gnutarget, scratch_chan); |
| 292 | if (temp_bfd == NULL) |
| 293 | perror_with_name (filename); |
| 294 | |
| 295 | if (!bfd_check_format (temp_bfd, bfd_core) && |
| 296 | !gdb_check_format (temp_bfd)) |
| 297 | { |
| 298 | /* Do it after the err msg */ |
| 299 | /* FIXME: should be checking for errors from bfd_close (for one thing, |
| 300 | on error it does not free all the storage associated with the |
| 301 | bfd). */ |
| 302 | make_cleanup_bfd_close (temp_bfd); |
| 303 | error ("\"%s\" is not a core dump: %s", |
| 304 | filename, bfd_errmsg (bfd_get_error ())); |
| 305 | } |
| 306 | |
| 307 | /* Looks semi-reasonable. Toss the old core file and work on the new. */ |
| 308 | |
| 309 | discard_cleanups (old_chain); /* Don't free filename any more */ |
| 310 | unpush_target (&core_ops); |
| 311 | core_bfd = temp_bfd; |
| 312 | old_chain = make_cleanup (core_close_cleanup, 0 /*ignore*/); |
| 313 | |
| 314 | /* Find a suitable core file handler to munch on core_bfd */ |
| 315 | core_vec = sniff_core_bfd (core_bfd); |
| 316 | |
| 317 | validate_files (); |
| 318 | |
| 319 | /* Find the data section */ |
| 320 | if (build_section_table (core_bfd, &core_ops.to_sections, |
| 321 | &core_ops.to_sections_end)) |
| 322 | error ("\"%s\": Can't find sections: %s", |
| 323 | bfd_get_filename (core_bfd), bfd_errmsg (bfd_get_error ())); |
| 324 | |
| 325 | /* If we have no exec file, try to set the architecture from the |
| 326 | core file. We don't do this unconditionally since an exec file |
| 327 | typically contains more information that helps us determine the |
| 328 | architecture than a core file. */ |
| 329 | if (!exec_bfd) |
| 330 | set_gdbarch_from_file (core_bfd); |
| 331 | |
| 332 | ontop = !push_target (&core_ops); |
| 333 | discard_cleanups (old_chain); |
| 334 | |
| 335 | p = bfd_core_file_failing_command (core_bfd); |
| 336 | if (p) |
| 337 | printf_filtered ("Core was generated by `%s'.\n", p); |
| 338 | |
| 339 | siggy = bfd_core_file_failing_signal (core_bfd); |
| 340 | if (siggy > 0) |
| 341 | /* NOTE: target_signal_from_host() converts a target signal value |
| 342 | into gdb's internal signal value. Unfortunately gdb's internal |
| 343 | value is called ``target_signal'' and this function got the |
| 344 | name ..._from_host(). */ |
| 345 | printf_filtered ("Program terminated with signal %d, %s.\n", siggy, |
| 346 | target_signal_to_string (target_signal_from_host (siggy))); |
| 347 | |
| 348 | /* Build up thread list from BFD sections. */ |
| 349 | |
| 350 | init_thread_list (); |
| 351 | bfd_map_over_sections (core_bfd, add_to_thread_list, |
| 352 | bfd_get_section_by_name (core_bfd, ".reg")); |
| 353 | |
| 354 | if (ontop) |
| 355 | { |
| 356 | /* Fetch all registers from core file. */ |
| 357 | target_fetch_registers (-1); |
| 358 | |
| 359 | /* Add symbols and section mappings for any shared libraries. */ |
| 360 | #ifdef SOLIB_ADD |
| 361 | catch_errors (solib_add_stub, &from_tty, (char *) 0, |
| 362 | RETURN_MASK_ALL); |
| 363 | #endif |
| 364 | |
| 365 | /* Now, set up the frame cache, and print the top of stack. */ |
| 366 | flush_cached_frames (); |
| 367 | select_frame (get_current_frame ()); |
| 368 | print_stack_frame (deprecated_selected_frame, |
| 369 | frame_relative_level (deprecated_selected_frame), 1); |
| 370 | } |
| 371 | else |
| 372 | { |
| 373 | warning ( |
| 374 | "you won't be able to access this core file until you terminate\n\ |
| 375 | your %s; do ``info files''", target_longname); |
| 376 | } |
| 377 | } |
| 378 | |
| 379 | static void |
| 380 | core_detach (char *args, int from_tty) |
| 381 | { |
| 382 | if (args) |
| 383 | error ("Too many arguments"); |
| 384 | unpush_target (&core_ops); |
| 385 | reinit_frame_cache (); |
| 386 | if (from_tty) |
| 387 | printf_filtered ("No core file now.\n"); |
| 388 | } |
| 389 | |
| 390 | |
| 391 | /* Try to retrieve registers from a section in core_bfd, and supply |
| 392 | them to core_vec->core_read_registers, as the register set numbered |
| 393 | WHICH. |
| 394 | |
| 395 | If inferior_ptid is zero, do the single-threaded thing: look for a |
| 396 | section named NAME. If inferior_ptid is non-zero, do the |
| 397 | multi-threaded thing: look for a section named "NAME/PID", where |
| 398 | PID is the shortest ASCII decimal representation of inferior_ptid. |
| 399 | |
| 400 | HUMAN_NAME is a human-readable name for the kind of registers the |
| 401 | NAME section contains, for use in error messages. |
| 402 | |
| 403 | If REQUIRED is non-zero, print an error if the core file doesn't |
| 404 | have a section by the appropriate name. Otherwise, just do nothing. */ |
| 405 | |
| 406 | static void |
| 407 | get_core_register_section (char *name, |
| 408 | int which, |
| 409 | char *human_name, |
| 410 | int required) |
| 411 | { |
| 412 | char section_name[100]; |
| 413 | sec_ptr section; |
| 414 | bfd_size_type size; |
| 415 | char *contents; |
| 416 | |
| 417 | if (PIDGET (inferior_ptid)) |
| 418 | sprintf (section_name, "%s/%d", name, PIDGET (inferior_ptid)); |
| 419 | else |
| 420 | strcpy (section_name, name); |
| 421 | |
| 422 | section = bfd_get_section_by_name (core_bfd, section_name); |
| 423 | if (! section) |
| 424 | { |
| 425 | if (required) |
| 426 | warning ("Couldn't find %s registers in core file.\n", human_name); |
| 427 | return; |
| 428 | } |
| 429 | |
| 430 | size = bfd_section_size (core_bfd, section); |
| 431 | contents = alloca (size); |
| 432 | if (! bfd_get_section_contents (core_bfd, section, contents, |
| 433 | (file_ptr) 0, size)) |
| 434 | { |
| 435 | warning ("Couldn't read %s registers from `%s' section in core file.\n", |
| 436 | human_name, name); |
| 437 | return; |
| 438 | } |
| 439 | |
| 440 | core_vec->core_read_registers (contents, size, which, |
| 441 | ((CORE_ADDR) |
| 442 | bfd_section_vma (core_bfd, section))); |
| 443 | } |
| 444 | |
| 445 | |
| 446 | /* Get the registers out of a core file. This is the machine- |
| 447 | independent part. Fetch_core_registers is the machine-dependent |
| 448 | part, typically implemented in the xm-file for each architecture. */ |
| 449 | |
| 450 | /* We just get all the registers, so we don't use regno. */ |
| 451 | |
| 452 | static void |
| 453 | get_core_registers (int regno) |
| 454 | { |
| 455 | int status; |
| 456 | |
| 457 | if (core_vec == NULL |
| 458 | || core_vec->core_read_registers == NULL) |
| 459 | { |
| 460 | fprintf_filtered (gdb_stderr, |
| 461 | "Can't fetch registers from this type of core file\n"); |
| 462 | return; |
| 463 | } |
| 464 | |
| 465 | get_core_register_section (".reg", 0, "general-purpose", 1); |
| 466 | get_core_register_section (".reg2", 2, "floating-point", 0); |
| 467 | get_core_register_section (".reg-xfp", 3, "extended floating-point", 0); |
| 468 | |
| 469 | deprecated_registers_fetched (); |
| 470 | } |
| 471 | |
| 472 | static void |
| 473 | core_files_info (struct target_ops *t) |
| 474 | { |
| 475 | print_section_info (t, core_bfd); |
| 476 | } |
| 477 | \f |
| 478 | /* If mourn is being called in all the right places, this could be say |
| 479 | `gdb internal error' (since generic_mourn calls breakpoint_init_inferior). */ |
| 480 | |
| 481 | static int |
| 482 | ignore (CORE_ADDR addr, char *contents) |
| 483 | { |
| 484 | return 0; |
| 485 | } |
| 486 | |
| 487 | |
| 488 | /* Okay, let's be honest: threads gleaned from a core file aren't |
| 489 | exactly lively, are they? On the other hand, if we don't claim |
| 490 | that each & every one is alive, then we don't get any of them |
| 491 | to appear in an "info thread" command, which is quite a useful |
| 492 | behaviour. |
| 493 | */ |
| 494 | static int |
| 495 | core_file_thread_alive (ptid_t tid) |
| 496 | { |
| 497 | return 1; |
| 498 | } |
| 499 | |
| 500 | /* Fill in core_ops with its defined operations and properties. */ |
| 501 | |
| 502 | static void |
| 503 | init_core_ops (void) |
| 504 | { |
| 505 | core_ops.to_shortname = "core"; |
| 506 | core_ops.to_longname = "Local core dump file"; |
| 507 | core_ops.to_doc = |
| 508 | "Use a core file as a target. Specify the filename of the core file."; |
| 509 | core_ops.to_open = core_open; |
| 510 | core_ops.to_close = core_close; |
| 511 | core_ops.to_attach = find_default_attach; |
| 512 | core_ops.to_detach = core_detach; |
| 513 | core_ops.to_fetch_registers = get_core_registers; |
| 514 | core_ops.to_xfer_memory = xfer_memory; |
| 515 | core_ops.to_files_info = core_files_info; |
| 516 | core_ops.to_insert_breakpoint = ignore; |
| 517 | core_ops.to_remove_breakpoint = ignore; |
| 518 | core_ops.to_create_inferior = find_default_create_inferior; |
| 519 | core_ops.to_thread_alive = core_file_thread_alive; |
| 520 | core_ops.to_stratum = core_stratum; |
| 521 | core_ops.to_has_memory = 1; |
| 522 | core_ops.to_has_stack = 1; |
| 523 | core_ops.to_has_registers = 1; |
| 524 | core_ops.to_magic = OPS_MAGIC; |
| 525 | } |
| 526 | |
| 527 | /* non-zero if we should not do the add_target call in |
| 528 | _initialize_corelow; not initialized (i.e., bss) so that |
| 529 | the target can initialize it (i.e., data) if appropriate. |
| 530 | This needs to be set at compile time because we don't know |
| 531 | for sure whether the target's initialize routine is called |
| 532 | before us or after us. */ |
| 533 | int coreops_suppress_target; |
| 534 | |
| 535 | void |
| 536 | _initialize_corelow (void) |
| 537 | { |
| 538 | init_core_ops (); |
| 539 | |
| 540 | if (!coreops_suppress_target) |
| 541 | add_target (&core_ops); |
| 542 | } |