1/* Process record and replay target for GDB, the GNU debugger. 2 3 Copyright (C) 2008, 2009, 2010, 2011 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 "gdbcmd.h" 22#include "regcache.h" 23#include "gdbthread.h" 24#include "event-top.h" 25#include "exceptions.h" 26#include "completer.h" 27#include "arch-utils.h" 28#include "gdbcore.h" 29#include "exec.h" 30#include "record.h" 31#include "elf-bfd.h" 32#include "gcore.h" 33 34#include <signal.h> 35 36/* This module implements "target record", also known as "process 37 record and replay". This target sits on top of a "normal" target 38 (a target that "has execution"), and provides a record and replay 39 functionality, including reverse debugging. 40 41 Target record has two modes: recording, and replaying. 42 43 In record mode, we intercept the to_resume and to_wait methods. 44 Whenever gdb resumes the target, we run the target in single step 45 mode, and we build up an execution log in which, for each executed 46 instruction, we record all changes in memory and register state. 47 This is invisible to the user, to whom it just looks like an 48 ordinary debugging session (except for performance degredation). 49 50 In replay mode, instead of actually letting the inferior run as a 51 process, we simulate its execution by playing back the recorded 52 execution log. For each instruction in the log, we simulate the 53 instruction's side effects by duplicating the changes that it would 54 have made on memory and registers. */ 55 56#define DEFAULT_RECORD_INSN_MAX_NUM 200000 57 58#define RECORD_IS_REPLAY \ 59 (record_list->next || execution_direction == EXEC_REVERSE) 60 61#define RECORD_FILE_MAGIC netorder32(0x20091016) 62 63/* These are the core structs of the process record functionality. 64 65 A record_entry is a record of the value change of a register 66 ("record_reg") or a part of memory ("record_mem"). And each 67 instruction must have a struct record_entry ("record_end") that 68 indicates that this is the last struct record_entry of this 69 instruction. 70 71 Each struct record_entry is linked to "record_list" by "prev" and 72 "next" pointers. */ 73 74struct record_mem_entry 75{ 76 CORE_ADDR addr; 77 int len; 78 /* Set this flag if target memory for this entry 79 can no longer be accessed. */ 80 int mem_entry_not_accessible; 81 union 82 { 83 gdb_byte *ptr; 84 gdb_byte buf[sizeof (gdb_byte *)]; 85 } u; 86}; 87 88struct record_reg_entry 89{ 90 unsigned short num; 91 unsigned short len; 92 union 93 { 94 gdb_byte *ptr; 95 gdb_byte buf[2 * sizeof (gdb_byte *)]; 96 } u; 97}; 98 99struct record_end_entry 100{ 101 enum target_signal sigval; 102 ULONGEST insn_num; 103}; 104 105enum record_type 106{ 107 record_end = 0, 108 record_reg, 109 record_mem 110}; 111 112/* This is the data structure that makes up the execution log. 113 114 The execution log consists of a single linked list of entries 115 of type "struct record_entry". It is doubly linked so that it 116 can be traversed in either direction. 117 118 The start of the list is anchored by a struct called 119 "record_first". The pointer "record_list" either points to the 120 last entry that was added to the list (in record mode), or to the 121 next entry in the list that will be executed (in replay mode). 122 123 Each list element (struct record_entry), in addition to next and 124 prev pointers, consists of a union of three entry types: mem, reg, 125 and end. A field called "type" determines which entry type is 126 represented by a given list element. 127 128 Each instruction that is added to the execution log is represented 129 by a variable number of list elements ('entries'). The instruction 130 will have one "reg" entry for each register that is changed by 131 executing the instruction (including the PC in every case). It 132 will also have one "mem" entry for each memory change. Finally, 133 each instruction will have an "end" entry that separates it from 134 the changes associated with the next instruction. */ 135 136struct record_entry 137{ 138 struct record_entry *prev; 139 struct record_entry *next; 140 enum record_type type; 141 union 142 { 143 /* reg */ 144 struct record_reg_entry reg; 145 /* mem */ 146 struct record_mem_entry mem; 147 /* end */ 148 struct record_end_entry end; 149 } u; 150}; 151 152/* This is the debug switch for process record. */ 153int record_debug = 0; 154 155/* If true, query if PREC cannot record memory 156 change of next instruction. */ 157int record_memory_query = 0; 158 159struct record_core_buf_entry 160{ 161 struct record_core_buf_entry *prev; 162 struct target_section *p; 163 bfd_byte *buf; 164}; 165 166/* Record buf with core target. */ 167static gdb_byte *record_core_regbuf = NULL; 168static struct target_section *record_core_start; 169static struct target_section *record_core_end; 170static struct record_core_buf_entry *record_core_buf_list = NULL; 171 172/* The following variables are used for managing the linked list that 173 represents the execution log. 174 175 record_first is the anchor that holds down the beginning of the list. 176 177 record_list serves two functions: 178 1) In record mode, it anchors the end of the list. 179 2) In replay mode, it traverses the list and points to 180 the next instruction that must be emulated. 181 182 record_arch_list_head and record_arch_list_tail are used to manage 183 a separate list, which is used to build up the change elements of 184 the currently executing instruction during record mode. When this 185 instruction has been completely annotated in the "arch list", it 186 will be appended to the main execution log. */ 187 188static struct record_entry record_first; 189static struct record_entry *record_list = &record_first; 190static struct record_entry *record_arch_list_head = NULL; 191static struct record_entry *record_arch_list_tail = NULL; 192 193/* 1 ask user. 0 auto delete the last struct record_entry. */ 194static int record_stop_at_limit = 1; 195/* Maximum allowed number of insns in execution log. */ 196static unsigned int record_insn_max_num = DEFAULT_RECORD_INSN_MAX_NUM; 197/* Actual count of insns presently in execution log. */ 198static int record_insn_num = 0; 199/* Count of insns logged so far (may be larger 200 than count of insns presently in execution log). */ 201static ULONGEST record_insn_count; 202 203/* The target_ops of process record. */ 204static struct target_ops record_ops; 205static struct target_ops record_core_ops; 206 207/* The beneath function pointers. */ 208static struct target_ops *record_beneath_to_resume_ops; 209static void (*record_beneath_to_resume) (struct target_ops *, ptid_t, int, 210 enum target_signal); 211static struct target_ops *record_beneath_to_wait_ops; 212static ptid_t (*record_beneath_to_wait) (struct target_ops *, ptid_t, 213 struct target_waitstatus *, 214 int); 215static struct target_ops *record_beneath_to_store_registers_ops; 216static void (*record_beneath_to_store_registers) (struct target_ops *, 217 struct regcache *, 218 int regno); 219static struct target_ops *record_beneath_to_xfer_partial_ops; 220static LONGEST (*record_beneath_to_xfer_partial) (struct target_ops *ops, 221 enum target_object object, 222 const char *annex, 223 gdb_byte *readbuf, 224 const gdb_byte *writebuf, 225 ULONGEST offset, 226 LONGEST len); 227static int (*record_beneath_to_insert_breakpoint) (struct gdbarch *, 228 struct bp_target_info *); 229static int (*record_beneath_to_remove_breakpoint) (struct gdbarch *, 230 struct bp_target_info *); 231static int (*record_beneath_to_stopped_by_watchpoint) (void); 232static int (*record_beneath_to_stopped_data_address) (struct target_ops *, 233 CORE_ADDR *); 234 235/* Alloc and free functions for record_reg, record_mem, and record_end 236 entries. */ 237 238/* Alloc a record_reg record entry. */ 239 240static inline struct record_entry * 241record_reg_alloc (struct regcache *regcache, int regnum) 242{ 243 struct record_entry *rec; 244 struct gdbarch *gdbarch = get_regcache_arch (regcache); 245 246 rec = (struct record_entry *) xcalloc (1, sizeof (struct record_entry)); 247 rec->type = record_reg; 248 rec->u.reg.num = regnum; 249 rec->u.reg.len = register_size (gdbarch, regnum); 250 if (rec->u.reg.len > sizeof (rec->u.reg.u.buf)) 251 rec->u.reg.u.ptr = (gdb_byte *) xmalloc (rec->u.reg.len); 252 253 return rec; 254} 255 256/* Free a record_reg record entry. */ 257 258static inline void 259record_reg_release (struct record_entry *rec) 260{ 261 gdb_assert (rec->type == record_reg); 262 if (rec->u.reg.len > sizeof (rec->u.reg.u.buf)) 263 xfree (rec->u.reg.u.ptr); 264 xfree (rec); 265} 266 267/* Alloc a record_mem record entry. */ 268 269static inline struct record_entry * 270record_mem_alloc (CORE_ADDR addr, int len) 271{ 272 struct record_entry *rec; 273 274 rec = (struct record_entry *) xcalloc (1, sizeof (struct record_entry)); 275 rec->type = record_mem; 276 rec->u.mem.addr = addr; 277 rec->u.mem.len = len; 278 if (rec->u.mem.len > sizeof (rec->u.mem.u.buf)) 279 rec->u.mem.u.ptr = (gdb_byte *) xmalloc (len); 280 281 return rec; 282} 283 284/* Free a record_mem record entry. */ 285 286static inline void 287record_mem_release (struct record_entry *rec) 288{ 289 gdb_assert (rec->type == record_mem); 290 if (rec->u.mem.len > sizeof (rec->u.mem.u.buf)) 291 xfree (rec->u.mem.u.ptr); 292 xfree (rec); 293} 294 295/* Alloc a record_end record entry. */ 296 297static inline struct record_entry * 298record_end_alloc (void) 299{ 300 struct record_entry *rec; 301 302 rec = (struct record_entry *) xcalloc (1, sizeof (struct record_entry)); 303 rec->type = record_end; 304 305 return rec; 306} 307 308/* Free a record_end record entry. */ 309 310static inline void 311record_end_release (struct record_entry *rec) 312{ 313 xfree (rec); 314} 315 316/* Free one record entry, any type. 317 Return entry->type, in case caller wants to know. */ 318 319static inline enum record_type 320record_entry_release (struct record_entry *rec) 321{ 322 enum record_type type = rec->type; 323 324 switch (type) { 325 case record_reg: 326 record_reg_release (rec); 327 break; 328 case record_mem: 329 record_mem_release (rec); 330 break; 331 case record_end: 332 record_end_release (rec); 333 break; 334 } 335 return type; 336} 337 338/* Free all record entries in list pointed to by REC. */ 339 340static void 341record_list_release (struct record_entry *rec) 342{ 343 if (!rec) 344 return; 345 346 while (rec->next) 347 rec = rec->next; 348 349 while (rec->prev) 350 { 351 rec = rec->prev; 352 record_entry_release (rec->next); 353 } 354 355 if (rec == &record_first) 356 { 357 record_insn_num = 0; 358 record_first.next = NULL; 359 } 360 else 361 record_entry_release (rec); 362} 363 364/* Free all record entries forward of the given list position. */ 365 366static void 367record_list_release_following (struct record_entry *rec) 368{ 369 struct record_entry *tmp = rec->next; 370 371 rec->next = NULL; 372 while (tmp) 373 { 374 rec = tmp->next; 375 if (record_entry_release (tmp) == record_end) 376 { 377 record_insn_num--; 378 record_insn_count--; 379 } 380 tmp = rec; 381 } 382} 383 384/* Delete the first instruction from the beginning of the log, to make 385 room for adding a new instruction at the end of the log. 386 387 Note -- this function does not modify record_insn_num. */ 388 389static void 390record_list_release_first (void) 391{ 392 struct record_entry *tmp; 393 394 if (!record_first.next) 395 return; 396 397 /* Loop until a record_end. */ 398 while (1) 399 { 400 /* Cut record_first.next out of the linked list. */ 401 tmp = record_first.next; 402 record_first.next = tmp->next; 403 tmp->next->prev = &record_first; 404 405 /* tmp is now isolated, and can be deleted. */ 406 if (record_entry_release (tmp) == record_end) 407 break; /* End loop at first record_end. */ 408 409 if (!record_first.next) 410 { 411 gdb_assert (record_insn_num == 1); 412 break; /* End loop when list is empty. */ 413 } 414 } 415} 416 417/* Add a struct record_entry to record_arch_list. */ 418 419static void 420record_arch_list_add (struct record_entry *rec) 421{ 422 if (record_debug > 1) 423 fprintf_unfiltered (gdb_stdlog, 424 "Process record: record_arch_list_add %s.\n", 425 host_address_to_string (rec)); 426 427 if (record_arch_list_tail) 428 { 429 record_arch_list_tail->next = rec; 430 rec->prev = record_arch_list_tail; 431 record_arch_list_tail = rec; 432 } 433 else 434 { 435 record_arch_list_head = rec; 436 record_arch_list_tail = rec; 437 } 438} 439 440/* Return the value storage location of a record entry. */ 441static inline gdb_byte * 442record_get_loc (struct record_entry *rec) 443{ 444 switch (rec->type) { 445 case record_mem: 446 if (rec->u.mem.len > sizeof (rec->u.mem.u.buf)) 447 return rec->u.mem.u.ptr; 448 else 449 return rec->u.mem.u.buf; 450 case record_reg: 451 if (rec->u.reg.len > sizeof (rec->u.reg.u.buf)) 452 return rec->u.reg.u.ptr; 453 else 454 return rec->u.reg.u.buf; 455 case record_end: 456 default: 457 gdb_assert_not_reached ("unexpected record_entry type"); 458 return NULL; 459 } 460} 461 462/* Record the value of a register NUM to record_arch_list. */ 463 464int 465record_arch_list_add_reg (struct regcache *regcache, int regnum) 466{ 467 struct record_entry *rec; 468 469 if (record_debug > 1) 470 fprintf_unfiltered (gdb_stdlog, 471 "Process record: add register num = %d to " 472 "record list.\n", 473 regnum); 474 475 rec = record_reg_alloc (regcache, regnum); 476 477 regcache_raw_read (regcache, regnum, record_get_loc (rec)); 478 479 record_arch_list_add (rec); 480 481 return 0; 482} 483 484/* Record the value of a region of memory whose address is ADDR and 485 length is LEN to record_arch_list. */ 486 487int 488record_arch_list_add_mem (CORE_ADDR addr, int len) 489{ 490 struct record_entry *rec; 491 492 if (record_debug > 1) 493 fprintf_unfiltered (gdb_stdlog, 494 "Process record: add mem addr = %s len = %d to " 495 "record list.\n", 496 paddress (target_gdbarch, addr), len); 497 498 if (!addr) /* FIXME: Why? Some arch must permit it... */ 499 return 0; 500 501 rec = record_mem_alloc (addr, len); 502 503 if (target_read_memory (addr, record_get_loc (rec), len)) 504 { 505 if (record_debug) 506 fprintf_unfiltered (gdb_stdlog, 507 "Process record: error reading memory at " 508 "addr = %s len = %d.\n", 509 paddress (target_gdbarch, addr), len); 510 record_mem_release (rec); 511 return -1; 512 } 513 514 record_arch_list_add (rec); 515 516 return 0; 517} 518 519/* Add a record_end type struct record_entry to record_arch_list. */ 520 521int 522record_arch_list_add_end (void) 523{ 524 struct record_entry *rec; 525 526 if (record_debug > 1) 527 fprintf_unfiltered (gdb_stdlog, 528 "Process record: add end to arch list.\n"); 529 530 rec = record_end_alloc (); 531 rec->u.end.sigval = TARGET_SIGNAL_0; 532 rec->u.end.insn_num = ++record_insn_count; 533 534 record_arch_list_add (rec); 535 536 return 0; 537} 538 539static void 540record_check_insn_num (int set_terminal) 541{ 542 if (record_insn_max_num) 543 { 544 gdb_assert (record_insn_num <= record_insn_max_num); 545 if (record_insn_num == record_insn_max_num) 546 { 547 /* Ask user what to do. */ 548 if (record_stop_at_limit) 549 { 550 int q; 551 552 if (set_terminal) 553 target_terminal_ours (); 554 q = yquery (_("Do you want to auto delete previous execution " 555 "log entries when record/replay buffer becomes " 556 "full (record stop-at-limit)?")); 557 if (set_terminal) 558 target_terminal_inferior (); 559 if (q) 560 record_stop_at_limit = 0; 561 else 562 error (_("Process record: stopped by user.")); 563 } 564 } 565 } 566} 567 568static void 569record_arch_list_cleanups (void *ignore) 570{ 571 record_list_release (record_arch_list_tail); 572} 573 574/* Before inferior step (when GDB record the running message, inferior 575 only can step), GDB will call this function to record the values to 576 record_list. This function will call gdbarch_process_record to 577 record the running message of inferior and set them to 578 record_arch_list, and add it to record_list. */ 579 580static int 581record_message (struct regcache *regcache, enum target_signal signal) 582{ 583 int ret; 584 struct gdbarch *gdbarch = get_regcache_arch (regcache); 585 struct cleanup *old_cleanups = make_cleanup (record_arch_list_cleanups, 0); 586 587 record_arch_list_head = NULL; 588 record_arch_list_tail = NULL; 589 590 /* Check record_insn_num. */ 591 record_check_insn_num (1); 592 593 /* If gdb sends a signal value to target_resume, 594 save it in the 'end' field of the previous instruction. 595 596 Maybe process record should record what really happened, 597 rather than what gdb pretends has happened. 598 599 So if Linux delivered the signal to the child process during 600 the record mode, we will record it and deliver it again in 601 the replay mode. 602 603 If user says "ignore this signal" during the record mode, then 604 it will be ignored again during the replay mode (no matter if 605 the user says something different, like "deliver this signal" 606 during the replay mode). 607 608 User should understand that nothing he does during the replay 609 mode will change the behavior of the child. If he tries, 610 then that is a user error. 611 612 But we should still deliver the signal to gdb during the replay, 613 if we delivered it during the recording. Therefore we should 614 record the signal during record_wait, not record_resume. */ 615 if (record_list != &record_first) /* FIXME better way to check */ 616 { 617 gdb_assert (record_list->type == record_end); 618 record_list->u.end.sigval = signal; 619 } 620 621 if (signal == TARGET_SIGNAL_0 622 || !gdbarch_process_record_signal_p (gdbarch)) 623 ret = gdbarch_process_record (gdbarch, 624 regcache, 625 regcache_read_pc (regcache)); 626 else 627 ret = gdbarch_process_record_signal (gdbarch, 628 regcache, 629 signal); 630 631 if (ret > 0) 632 error (_("Process record: inferior program stopped.")); 633 if (ret < 0) 634 error (_("Process record: failed to record execution log.")); 635 636 discard_cleanups (old_cleanups); 637 638 record_list->next = record_arch_list_head; 639 record_arch_list_head->prev = record_list; 640 record_list = record_arch_list_tail; 641 642 if (record_insn_num == record_insn_max_num && record_insn_max_num) 643 record_list_release_first (); 644 else 645 record_insn_num++; 646 647 return 1; 648} 649 650struct record_message_args { 651 struct regcache *regcache; 652 enum target_signal signal; 653}; 654 655static int 656record_message_wrapper (void *args) 657{ 658 struct record_message_args *record_args = args; 659 660 return record_message (record_args->regcache, record_args->signal); 661} 662 663static int 664record_message_wrapper_safe (struct regcache *regcache, 665 enum target_signal signal) 666{ 667 struct record_message_args args; 668 669 args.regcache = regcache; 670 args.signal = signal; 671 672 return catch_errors (record_message_wrapper, &args, NULL, RETURN_MASK_ALL); 673} 674 675/* Set to 1 if record_store_registers and record_xfer_partial 676 doesn't need record. */ 677 678static int record_gdb_operation_disable = 0; 679 680struct cleanup * 681record_gdb_operation_disable_set (void) 682{ 683 struct cleanup *old_cleanups = NULL; 684 685 old_cleanups = 686 make_cleanup_restore_integer (&record_gdb_operation_disable); 687 record_gdb_operation_disable = 1; 688 689 return old_cleanups; 690} 691 692/* Flag set to TRUE for target_stopped_by_watchpoint. */ 693static int record_hw_watchpoint = 0; 694 695/* Execute one instruction from the record log. Each instruction in 696 the log will be represented by an arbitrary sequence of register 697 entries and memory entries, followed by an 'end' entry. */ 698 699static inline void 700record_exec_insn (struct regcache *regcache, struct gdbarch *gdbarch, 701 struct record_entry *entry) 702{ 703 switch (entry->type) 704 { 705 case record_reg: /* reg */ 706 { 707 gdb_byte reg[MAX_REGISTER_SIZE]; 708 709 if (record_debug > 1) 710 fprintf_unfiltered (gdb_stdlog, 711 "Process record: record_reg %s to " 712 "inferior num = %d.\n", 713 host_address_to_string (entry), 714 entry->u.reg.num); 715 716 regcache_cooked_read (regcache, entry->u.reg.num, reg); 717 regcache_cooked_write (regcache, entry->u.reg.num, 718 record_get_loc (entry)); 719 memcpy (record_get_loc (entry), reg, entry->u.reg.len); 720 } 721 break; 722 723 case record_mem: /* mem */ 724 { 725 /* Nothing to do if the entry is flagged not_accessible. */ 726 if (!entry->u.mem.mem_entry_not_accessible) 727 { 728 gdb_byte *mem = alloca (entry->u.mem.len); 729 730 if (record_debug > 1) 731 fprintf_unfiltered (gdb_stdlog, 732 "Process record: record_mem %s to " 733 "inferior addr = %s len = %d.\n", 734 host_address_to_string (entry), 735 paddress (gdbarch, entry->u.mem.addr), 736 entry->u.mem.len); 737 738 if (target_read_memory (entry->u.mem.addr, mem, entry->u.mem.len)) 739 { 740 entry->u.mem.mem_entry_not_accessible = 1; 741 if (record_debug) 742 warning (_("Process record: error reading memory at " 743 "addr = %s len = %d."), 744 paddress (gdbarch, entry->u.mem.addr), 745 entry->u.mem.len); 746 } 747 else 748 { 749 if (target_write_memory (entry->u.mem.addr, 750 record_get_loc (entry), 751 entry->u.mem.len)) 752 { 753 entry->u.mem.mem_entry_not_accessible = 1; 754 if (record_debug) 755 warning (_("Process record: error writing memory at " 756 "addr = %s len = %d."), 757 paddress (gdbarch, entry->u.mem.addr), 758 entry->u.mem.len); 759 } 760 else 761 { 762 memcpy (record_get_loc (entry), mem, entry->u.mem.len); 763 764 /* We've changed memory --- check if a hardware 765 watchpoint should trap. Note that this 766 presently assumes the target beneath supports 767 continuable watchpoints. On non-continuable 768 watchpoints target, we'll want to check this 769 _before_ actually doing the memory change, and 770 not doing the change at all if the watchpoint 771 traps. */ 772 if (hardware_watchpoint_inserted_in_range 773 (get_regcache_aspace (regcache), 774 entry->u.mem.addr, entry->u.mem.len)) 775 record_hw_watchpoint = 1; 776 } 777 } 778 } 779 } 780 break; 781 } 782} 783 784static struct target_ops *tmp_to_resume_ops; 785static void (*tmp_to_resume) (struct target_ops *, ptid_t, int, 786 enum target_signal); 787static struct target_ops *tmp_to_wait_ops; 788static ptid_t (*tmp_to_wait) (struct target_ops *, ptid_t, 789 struct target_waitstatus *, 790 int); 791static struct target_ops *tmp_to_store_registers_ops; 792static void (*tmp_to_store_registers) (struct target_ops *, 793 struct regcache *, 794 int regno); 795static struct target_ops *tmp_to_xfer_partial_ops; 796static LONGEST (*tmp_to_xfer_partial) (struct target_ops *ops, 797 enum target_object object, 798 const char *annex, 799 gdb_byte *readbuf, 800 const gdb_byte *writebuf, 801 ULONGEST offset, 802 LONGEST len); 803static int (*tmp_to_insert_breakpoint) (struct gdbarch *, 804 struct bp_target_info *); 805static int (*tmp_to_remove_breakpoint) (struct gdbarch *, 806 struct bp_target_info *); 807static int (*tmp_to_stopped_by_watchpoint) (void); 808static int (*tmp_to_stopped_data_address) (struct target_ops *, CORE_ADDR *); 809 810static void record_restore (void); 811 812/* Open the process record target. */ 813 814static void 815record_core_open_1 (char *name, int from_tty) 816{ 817 struct regcache *regcache = get_current_regcache (); 818 int regnum = gdbarch_num_regs (get_regcache_arch (regcache)); 819 int i; 820 821 /* Get record_core_regbuf. */ 822 target_fetch_registers (regcache, -1); 823 record_core_regbuf = xmalloc (MAX_REGISTER_SIZE * regnum); 824 for (i = 0; i < regnum; i ++) 825 regcache_raw_collect (regcache, i, 826 record_core_regbuf + MAX_REGISTER_SIZE * i); 827 828 /* Get record_core_start and record_core_end. */ 829 if (build_section_table (core_bfd, &record_core_start, &record_core_end)) 830 { 831 xfree (record_core_regbuf); 832 record_core_regbuf = NULL; 833 error (_("\"%s\": Can't find sections: %s"), 834 bfd_get_filename (core_bfd), bfd_errmsg (bfd_get_error ())); 835 } 836 837 push_target (&record_core_ops); 838 record_restore (); 839} 840 841/* "to_open" target method for 'live' processes. */ 842 843static void 844record_open_1 (char *name, int from_tty) 845{ 846 if (record_debug) 847 fprintf_unfiltered (gdb_stdlog, "Process record: record_open\n"); 848 849 /* check exec */ 850 if (!target_has_execution) 851 error (_("Process record: the program is not being run.")); 852 if (non_stop) 853 error (_("Process record target can't debug inferior in non-stop mode " 854 "(non-stop).")); 855 if (target_async_permitted) 856 error (_("Process record target can't debug inferior in asynchronous " 857 "mode (target-async).")); 858 859 if (!gdbarch_process_record_p (target_gdbarch)) 860 error (_("Process record: the current architecture doesn't support " 861 "record function.")); 862 863 if (!tmp_to_resume) 864 error (_("Could not find 'to_resume' method on the target stack.")); 865 if (!tmp_to_wait) 866 error (_("Could not find 'to_wait' method on the target stack.")); 867 if (!tmp_to_store_registers) 868 error (_("Could not find 'to_store_registers' " 869 "method on the target stack.")); 870 if (!tmp_to_insert_breakpoint) 871 error (_("Could not find 'to_insert_breakpoint' " 872 "method on the target stack.")); 873 if (!tmp_to_remove_breakpoint) 874 error (_("Could not find 'to_remove_breakpoint' " 875 "method on the target stack.")); 876 if (!tmp_to_stopped_by_watchpoint) 877 error (_("Could not find 'to_stopped_by_watchpoint' " 878 "method on the target stack.")); 879 if (!tmp_to_stopped_data_address) 880 error (_("Could not find 'to_stopped_data_address' " 881 "method on the target stack.")); 882 883 push_target (&record_ops); 884} 885 886/* "to_open" target method. Open the process record target. */ 887 888static void 889record_open (char *name, int from_tty) 890{ 891 struct target_ops *t; 892 893 if (record_debug) 894 fprintf_unfiltered (gdb_stdlog, "Process record: record_open\n"); 895 896 /* Check if record target is already running. */ 897 if (current_target.to_stratum == record_stratum) 898 error (_("Process record target already running. Use \"record stop\" to " 899 "stop record target first.")); 900 901 /* Reset the tmp beneath pointers. */ 902 tmp_to_resume_ops = NULL; 903 tmp_to_resume = NULL; 904 tmp_to_wait_ops = NULL; 905 tmp_to_wait = NULL; 906 tmp_to_store_registers_ops = NULL; 907 tmp_to_store_registers = NULL; 908 tmp_to_xfer_partial_ops = NULL; 909 tmp_to_xfer_partial = NULL; 910 tmp_to_insert_breakpoint = NULL; 911 tmp_to_remove_breakpoint = NULL; 912 tmp_to_stopped_by_watchpoint = NULL; 913 tmp_to_stopped_data_address = NULL; 914 915 /* Set the beneath function pointers. */ 916 for (t = current_target.beneath; t != NULL; t = t->beneath) 917 { 918 if (!tmp_to_resume) 919 { 920 tmp_to_resume = t->to_resume; 921 tmp_to_resume_ops = t; 922 } 923 if (!tmp_to_wait) 924 { 925 tmp_to_wait = t->to_wait; 926 tmp_to_wait_ops = t; 927 } 928 if (!tmp_to_store_registers) 929 { 930 tmp_to_store_registers = t->to_store_registers; 931 tmp_to_store_registers_ops = t; 932 } 933 if (!tmp_to_xfer_partial) 934 { 935 tmp_to_xfer_partial = t->to_xfer_partial; 936 tmp_to_xfer_partial_ops = t; 937 } 938 if (!tmp_to_insert_breakpoint) 939 tmp_to_insert_breakpoint = t->to_insert_breakpoint; 940 if (!tmp_to_remove_breakpoint) 941 tmp_to_remove_breakpoint = t->to_remove_breakpoint; 942 if (!tmp_to_stopped_by_watchpoint) 943 tmp_to_stopped_by_watchpoint = t->to_stopped_by_watchpoint; 944 if (!tmp_to_stopped_data_address) 945 tmp_to_stopped_data_address = t->to_stopped_data_address; 946 } 947 if (!tmp_to_xfer_partial) 948 error (_("Could not find 'to_xfer_partial' method on the target stack.")); 949 950 /* Reset */ 951 record_insn_num = 0; 952 record_insn_count = 0; 953 record_list = &record_first; 954 record_list->next = NULL; 955 956 /* Set the tmp beneath pointers to beneath pointers. */ 957 record_beneath_to_resume_ops = tmp_to_resume_ops; 958 record_beneath_to_resume = tmp_to_resume; 959 record_beneath_to_wait_ops = tmp_to_wait_ops; 960 record_beneath_to_wait = tmp_to_wait; 961 record_beneath_to_store_registers_ops = tmp_to_store_registers_ops; 962 record_beneath_to_store_registers = tmp_to_store_registers; 963 record_beneath_to_xfer_partial_ops = tmp_to_xfer_partial_ops; 964 record_beneath_to_xfer_partial = tmp_to_xfer_partial; 965 record_beneath_to_insert_breakpoint = tmp_to_insert_breakpoint; 966 record_beneath_to_remove_breakpoint = tmp_to_remove_breakpoint; 967 record_beneath_to_stopped_by_watchpoint = tmp_to_stopped_by_watchpoint; 968 record_beneath_to_stopped_data_address = tmp_to_stopped_data_address; 969 970 if (core_bfd) 971 record_core_open_1 (name, from_tty); 972 else 973 record_open_1 (name, from_tty); 974} 975 976/* "to_close" target method. Close the process record target. */ 977 978static void 979record_close (int quitting) 980{ 981 struct record_core_buf_entry *entry; 982 983 if (record_debug) 984 fprintf_unfiltered (gdb_stdlog, "Process record: record_close\n"); 985 986 record_list_release (record_list); 987 988 /* Release record_core_regbuf. */ 989 if (record_core_regbuf) 990 { 991 xfree (record_core_regbuf); 992 record_core_regbuf = NULL; 993 } 994 995 /* Release record_core_buf_list. */ 996 if (record_core_buf_list) 997 { 998 for (entry = record_core_buf_list->prev; entry; entry = entry->prev) 999 { 1000 xfree (record_core_buf_list); 1001 record_core_buf_list = entry; 1002 } 1003 record_core_buf_list = NULL; 1004 } 1005} 1006 1007static int record_resume_step = 0; 1008 1009/* "to_resume" target method. Resume the process record target. */ 1010 1011static void 1012record_resume (struct target_ops *ops, ptid_t ptid, int step, 1013 enum target_signal signal) 1014{ 1015 record_resume_step = step; 1016 1017 if (!RECORD_IS_REPLAY) 1018 { 1019 struct gdbarch *gdbarch = target_thread_architecture (ptid); 1020 1021 record_message (get_current_regcache (), signal); 1022 1023 if (!step) 1024 { 1025 /* This is not hard single step. */ 1026 if (!gdbarch_software_single_step_p (gdbarch)) 1027 { 1028 /* This is a normal continue. */ 1029 step = 1; 1030 } 1031 else 1032 { 1033 /* This arch support soft sigle step. */ 1034 if (single_step_breakpoints_inserted ()) 1035 { 1036 /* This is a soft single step. */ 1037 record_resume_step = 1; 1038 } 1039 else 1040 { 1041 /* This is a continue. 1042 Try to insert a soft single step breakpoint. */ 1043 if (!gdbarch_software_single_step (gdbarch, 1044 get_current_frame ())) 1045 { 1046 /* This system don't want use soft single step. 1047 Use hard sigle step. */ 1048 step = 1; 1049 } 1050 } 1051 } 1052 } 1053 1054 record_beneath_to_resume (record_beneath_to_resume_ops, 1055 ptid, step, signal); 1056 } 1057} 1058 1059static int record_get_sig = 0; 1060 1061/* SIGINT signal handler, registered by "to_wait" method. */ 1062 1063static void 1064record_sig_handler (int signo) 1065{ 1066 if (record_debug) 1067 fprintf_unfiltered (gdb_stdlog, "Process record: get a signal\n"); 1068 1069 /* It will break the running inferior in replay mode. */ 1070 record_resume_step = 1; 1071 1072 /* It will let record_wait set inferior status to get the signal 1073 SIGINT. */ 1074 record_get_sig = 1; 1075} 1076 1077static void 1078record_wait_cleanups (void *ignore) 1079{ 1080 if (execution_direction == EXEC_REVERSE) 1081 { 1082 if (record_list->next) 1083 record_list = record_list->next; 1084 } 1085 else 1086 record_list = record_list->prev; 1087} 1088 1089/* "to_wait" target method for process record target. 1090 1091 In record mode, the target is always run in singlestep mode 1092 (even when gdb says to continue). The to_wait method intercepts 1093 the stop events and determines which ones are to be passed on to 1094 gdb. Most stop events are just singlestep events that gdb is not 1095 to know about, so the to_wait method just records them and keeps 1096 singlestepping. 1097 1098 In replay mode, this function emulates the recorded execution log, 1099 one instruction at a time (forward or backward), and determines 1100 where to stop. */ 1101 1102static ptid_t 1103record_wait (struct target_ops *ops, 1104 ptid_t ptid, struct target_waitstatus *status, 1105 int options) 1106{ 1107 struct cleanup *set_cleanups = record_gdb_operation_disable_set (); 1108 1109 if (record_debug) 1110 fprintf_unfiltered (gdb_stdlog, 1111 "Process record: record_wait " 1112 "record_resume_step = %d\n", 1113 record_resume_step); 1114 1115 record_get_sig = 0; 1116 signal (SIGINT, record_sig_handler); 1117 1118 if (!RECORD_IS_REPLAY && ops != &record_core_ops) 1119 { 1120 if (record_resume_step) 1121 { 1122 /* This is a single step. */ 1123 return record_beneath_to_wait (record_beneath_to_wait_ops, 1124 ptid, status, options); 1125 } 1126 else 1127 { 1128 /* This is not a single step. */ 1129 ptid_t ret; 1130 CORE_ADDR tmp_pc; 1131 struct gdbarch *gdbarch = target_thread_architecture (inferior_ptid); 1132 1133 while (1) 1134 { 1135 ret = record_beneath_to_wait (record_beneath_to_wait_ops, 1136 ptid, status, options); 1137 1138 if (single_step_breakpoints_inserted ()) 1139 remove_single_step_breakpoints (); 1140 1141 if (record_resume_step) 1142 return ret; 1143 1144 /* Is this a SIGTRAP? */ 1145 if (status->kind == TARGET_WAITKIND_STOPPED 1146 && status->value.sig == TARGET_SIGNAL_TRAP) 1147 { 1148 struct regcache *regcache; 1149 struct address_space *aspace; 1150 1151 /* Yes -- this is likely our single-step finishing, 1152 but check if there's any reason the core would be 1153 interested in the event. */ 1154 1155 registers_changed (); 1156 regcache = get_current_regcache (); 1157 tmp_pc = regcache_read_pc (regcache); 1158 aspace = get_regcache_aspace (regcache); 1159 1160 if (target_stopped_by_watchpoint ()) 1161 { 1162 /* Always interested in watchpoints. */ 1163 } 1164 else if (breakpoint_inserted_here_p (aspace, tmp_pc)) 1165 { 1166 /* There is a breakpoint here. Let the core 1167 handle it. */ 1168 if (software_breakpoint_inserted_here_p (aspace, tmp_pc)) 1169 { 1170 struct gdbarch *gdbarch 1171 = get_regcache_arch (regcache); 1172 CORE_ADDR decr_pc_after_break 1173 = gdbarch_decr_pc_after_break (gdbarch); 1174 if (decr_pc_after_break) 1175 regcache_write_pc (regcache, 1176 tmp_pc + decr_pc_after_break); 1177 } 1178 } 1179 else 1180 { 1181 /* This is a single-step trap. Record the 1182 insn and issue another step. 1183 FIXME: this part can be a random SIGTRAP too. 1184 But GDB cannot handle it. */ 1185 int step = 1; 1186 1187 if (!record_message_wrapper_safe (regcache, 1188 TARGET_SIGNAL_0)) 1189 { 1190 status->kind = TARGET_WAITKIND_STOPPED; 1191 status->value.sig = TARGET_SIGNAL_0; 1192 break; 1193 } 1194 1195 if (gdbarch_software_single_step_p (gdbarch)) 1196 { 1197 /* Try to insert the software single step breakpoint. 1198 If insert success, set step to 0. */ 1199 set_executing (inferior_ptid, 0); 1200 reinit_frame_cache (); 1201 if (gdbarch_software_single_step (gdbarch, 1202 get_current_frame ())) 1203 step = 0; 1204 set_executing (inferior_ptid, 1); 1205 } 1206 1207 record_beneath_to_resume (record_beneath_to_resume_ops, 1208 ptid, step, 1209 TARGET_SIGNAL_0); 1210 continue; 1211 } 1212 } 1213 1214 /* The inferior is broken by a breakpoint or a signal. */ 1215 break; 1216 } 1217 1218 return ret; 1219 } 1220 } 1221 else 1222 { 1223 struct regcache *regcache = get_current_regcache (); 1224 struct gdbarch *gdbarch = get_regcache_arch (regcache); 1225 struct address_space *aspace = get_regcache_aspace (regcache); 1226 int continue_flag = 1; 1227 int first_record_end = 1; 1228 struct cleanup *old_cleanups = make_cleanup (record_wait_cleanups, 0); 1229 CORE_ADDR tmp_pc; 1230 1231 record_hw_watchpoint = 0; 1232 status->kind = TARGET_WAITKIND_STOPPED; 1233 1234 /* Check breakpoint when forward execute. */ 1235 if (execution_direction == EXEC_FORWARD) 1236 { 1237 tmp_pc = regcache_read_pc (regcache); 1238 if (breakpoint_inserted_here_p (aspace, tmp_pc)) 1239 { 1240 int decr_pc_after_break = gdbarch_decr_pc_after_break (gdbarch); 1241 1242 if (record_debug) 1243 fprintf_unfiltered (gdb_stdlog, 1244 "Process record: break at %s.\n", 1245 paddress (gdbarch, tmp_pc)); 1246 1247 if (decr_pc_after_break 1248 && !record_resume_step 1249 && software_breakpoint_inserted_here_p (aspace, tmp_pc)) 1250 regcache_write_pc (regcache, 1251 tmp_pc + decr_pc_after_break); 1252 goto replay_out; 1253 } 1254 } 1255 1256 /* If GDB is in terminal_inferior mode, it will not get the signal. 1257 And in GDB replay mode, GDB doesn't need to be in terminal_inferior 1258 mode, because inferior will not executed. 1259 Then set it to terminal_ours to make GDB get the signal. */ 1260 target_terminal_ours (); 1261 1262 /* In EXEC_FORWARD mode, record_list points to the tail of prev 1263 instruction. */ 1264 if (execution_direction == EXEC_FORWARD && record_list->next) 1265 record_list = record_list->next; 1266 1267 /* Loop over the record_list, looking for the next place to 1268 stop. */ 1269 do 1270 { 1271 /* Check for beginning and end of log. */ 1272 if (execution_direction == EXEC_REVERSE 1273 && record_list == &record_first) 1274 { 1275 /* Hit beginning of record log in reverse. */ 1276 status->kind = TARGET_WAITKIND_NO_HISTORY; 1277 break; 1278 } 1279 if (execution_direction != EXEC_REVERSE && !record_list->next) 1280 { 1281 /* Hit end of record log going forward. */ 1282 status->kind = TARGET_WAITKIND_NO_HISTORY; 1283 break; 1284 } 1285 1286 record_exec_insn (regcache, gdbarch, record_list); 1287 1288 if (record_list->type == record_end) 1289 { 1290 if (record_debug > 1) 1291 fprintf_unfiltered (gdb_stdlog, 1292 "Process record: record_end %s to " 1293 "inferior.\n", 1294 host_address_to_string (record_list)); 1295 1296 if (first_record_end && execution_direction == EXEC_REVERSE) 1297 { 1298 /* When reverse excute, the first record_end is the part of 1299 current instruction. */ 1300 first_record_end = 0; 1301 } 1302 else 1303 { 1304 /* In EXEC_REVERSE mode, this is the record_end of prev 1305 instruction. 1306 In EXEC_FORWARD mode, this is the record_end of current 1307 instruction. */ 1308 /* step */ 1309 if (record_resume_step) 1310 { 1311 if (record_debug > 1) 1312 fprintf_unfiltered (gdb_stdlog, 1313 "Process record: step.\n"); 1314 continue_flag = 0; 1315 } 1316 1317 /* check breakpoint */ 1318 tmp_pc = regcache_read_pc (regcache); 1319 if (breakpoint_inserted_here_p (aspace, tmp_pc)) 1320 { 1321 int decr_pc_after_break 1322 = gdbarch_decr_pc_after_break (gdbarch); 1323 1324 if (record_debug) 1325 fprintf_unfiltered (gdb_stdlog, 1326 "Process record: break " 1327 "at %s.\n", 1328 paddress (gdbarch, tmp_pc)); 1329 if (decr_pc_after_break 1330 && execution_direction == EXEC_FORWARD 1331 && !record_resume_step 1332 && software_breakpoint_inserted_here_p (aspace, 1333 tmp_pc)) 1334 regcache_write_pc (regcache, 1335 tmp_pc + decr_pc_after_break); 1336 continue_flag = 0; 1337 } 1338 1339 if (record_hw_watchpoint) 1340 { 1341 if (record_debug) 1342 fprintf_unfiltered (gdb_stdlog, 1343 "Process record: hit hw " 1344 "watchpoint.\n"); 1345 continue_flag = 0; 1346 } 1347 /* Check target signal */ 1348 if (record_list->u.end.sigval != TARGET_SIGNAL_0) 1349 /* FIXME: better way to check */ 1350 continue_flag = 0; 1351 } 1352 } 1353 1354 if (continue_flag) 1355 { 1356 if (execution_direction == EXEC_REVERSE) 1357 { 1358 if (record_list->prev) 1359 record_list = record_list->prev; 1360 } 1361 else 1362 { 1363 if (record_list->next) 1364 record_list = record_list->next; 1365 } 1366 } 1367 } 1368 while (continue_flag); 1369 1370replay_out: 1371 if (record_get_sig) 1372 status->value.sig = TARGET_SIGNAL_INT; 1373 else if (record_list->u.end.sigval != TARGET_SIGNAL_0) 1374 /* FIXME: better way to check */ 1375 status->value.sig = record_list->u.end.sigval; 1376 else 1377 status->value.sig = TARGET_SIGNAL_TRAP; 1378 1379 discard_cleanups (old_cleanups); 1380 } 1381 1382 signal (SIGINT, handle_sigint); 1383 1384 do_cleanups (set_cleanups); 1385 return inferior_ptid; 1386} 1387 1388static int 1389record_stopped_by_watchpoint (void) 1390{ 1391 if (RECORD_IS_REPLAY) 1392 return record_hw_watchpoint; 1393 else 1394 return record_beneath_to_stopped_by_watchpoint (); 1395} 1396 1397static int 1398record_stopped_data_address (struct target_ops *ops, CORE_ADDR *addr_p) 1399{ 1400 if (RECORD_IS_REPLAY) 1401 return 0; 1402 else 1403 return record_beneath_to_stopped_data_address (ops, addr_p); 1404} 1405 1406/* "to_disconnect" method for process record target. */ 1407 1408static void 1409record_disconnect (struct target_ops *target, char *args, int from_tty) 1410{ 1411 if (record_debug) 1412 fprintf_unfiltered (gdb_stdlog, "Process record: record_disconnect\n"); 1413 1414 unpush_target (&record_ops); 1415 target_disconnect (args, from_tty); 1416} 1417 1418/* "to_detach" method for process record target. */ 1419 1420static void 1421record_detach (struct target_ops *ops, char *args, int from_tty) 1422{ 1423 if (record_debug) 1424 fprintf_unfiltered (gdb_stdlog, "Process record: record_detach\n"); 1425 1426 unpush_target (&record_ops); 1427 target_detach (args, from_tty); 1428} 1429 1430/* "to_mourn_inferior" method for process record target. */ 1431 1432static void 1433record_mourn_inferior (struct target_ops *ops) 1434{ 1435 if (record_debug) 1436 fprintf_unfiltered (gdb_stdlog, "Process record: " 1437 "record_mourn_inferior\n"); 1438 1439 unpush_target (&record_ops); 1440 target_mourn_inferior (); 1441} 1442 1443/* Close process record target before killing the inferior process. */ 1444 1445static void 1446record_kill (struct target_ops *ops) 1447{ 1448 if (record_debug) 1449 fprintf_unfiltered (gdb_stdlog, "Process record: record_kill\n"); 1450 1451 unpush_target (&record_ops); 1452 target_kill (); 1453} 1454 1455/* Record registers change (by user or by GDB) to list as an instruction. */ 1456 1457static void 1458record_registers_change (struct regcache *regcache, int regnum) 1459{ 1460 /* Check record_insn_num. */ 1461 record_check_insn_num (0); 1462 1463 record_arch_list_head = NULL; 1464 record_arch_list_tail = NULL; 1465 1466 if (regnum < 0) 1467 { 1468 int i; 1469 1470 for (i = 0; i < gdbarch_num_regs (get_regcache_arch (regcache)); i++) 1471 { 1472 if (record_arch_list_add_reg (regcache, i)) 1473 { 1474 record_list_release (record_arch_list_tail); 1475 error (_("Process record: failed to record execution log.")); 1476 } 1477 } 1478 } 1479 else 1480 { 1481 if (record_arch_list_add_reg (regcache, regnum)) 1482 { 1483 record_list_release (record_arch_list_tail); 1484 error (_("Process record: failed to record execution log.")); 1485 } 1486 } 1487 if (record_arch_list_add_end ()) 1488 { 1489 record_list_release (record_arch_list_tail); 1490 error (_("Process record: failed to record execution log.")); 1491 } 1492 record_list->next = record_arch_list_head; 1493 record_arch_list_head->prev = record_list; 1494 record_list = record_arch_list_tail; 1495 1496 if (record_insn_num == record_insn_max_num && record_insn_max_num) 1497 record_list_release_first (); 1498 else 1499 record_insn_num++; 1500} 1501 1502/* "to_store_registers" method for process record target. */ 1503 1504static void 1505record_store_registers (struct target_ops *ops, struct regcache *regcache, 1506 int regno) 1507{ 1508 if (!record_gdb_operation_disable) 1509 { 1510 if (RECORD_IS_REPLAY) 1511 { 1512 int n; 1513 1514 /* Let user choose if he wants to write register or not. */ 1515 if (regno < 0) 1516 n = 1517 query (_("Because GDB is in replay mode, changing the " 1518 "value of a register will make the execution " 1519 "log unusable from this point onward. " 1520 "Change all registers?")); 1521 else 1522 n = 1523 query (_("Because GDB is in replay mode, changing the value " 1524 "of a register will make the execution log unusable " 1525 "from this point onward. Change register %s?"), 1526 gdbarch_register_name (get_regcache_arch (regcache), 1527 regno)); 1528 1529 if (!n) 1530 { 1531 /* Invalidate the value of regcache that was set in function 1532 "regcache_raw_write". */ 1533 if (regno < 0) 1534 { 1535 int i; 1536 1537 for (i = 0; 1538 i < gdbarch_num_regs (get_regcache_arch (regcache)); 1539 i++) 1540 regcache_invalidate (regcache, i); 1541 } 1542 else 1543 regcache_invalidate (regcache, regno); 1544 1545 error (_("Process record canceled the operation.")); 1546 } 1547 1548 /* Destroy the record from here forward. */ 1549 record_list_release_following (record_list); 1550 } 1551 1552 record_registers_change (regcache, regno); 1553 } 1554 record_beneath_to_store_registers (record_beneath_to_store_registers_ops, 1555 regcache, regno); 1556} 1557 1558/* "to_xfer_partial" method. Behavior is conditional on RECORD_IS_REPLAY. 1559 In replay mode, we cannot write memory unles we are willing to 1560 invalidate the record/replay log from this point forward. */ 1561 1562static LONGEST 1563record_xfer_partial (struct target_ops *ops, enum target_object object, 1564 const char *annex, gdb_byte *readbuf, 1565 const gdb_byte *writebuf, ULONGEST offset, LONGEST len) 1566{ 1567 if (!record_gdb_operation_disable 1568 && (object == TARGET_OBJECT_MEMORY 1569 || object == TARGET_OBJECT_RAW_MEMORY) && writebuf) 1570 { 1571 if (RECORD_IS_REPLAY) 1572 { 1573 /* Let user choose if he wants to write memory or not. */ 1574 if (!query (_("Because GDB is in replay mode, writing to memory " 1575 "will make the execution log unusable from this " 1576 "point onward. Write memory at address %s?"), 1577 paddress (target_gdbarch, offset))) 1578 error (_("Process record canceled the operation.")); 1579 1580 /* Destroy the record from here forward. */ 1581 record_list_release_following (record_list); 1582 } 1583 1584 /* Check record_insn_num */ 1585 record_check_insn_num (0); 1586 1587 /* Record registers change to list as an instruction. */ 1588 record_arch_list_head = NULL; 1589 record_arch_list_tail = NULL; 1590 if (record_arch_list_add_mem (offset, len)) 1591 { 1592 record_list_release (record_arch_list_tail); 1593 if (record_debug) 1594 fprintf_unfiltered (gdb_stdlog, 1595 "Process record: failed to record " 1596 "execution log."); 1597 return -1; 1598 } 1599 if (record_arch_list_add_end ()) 1600 { 1601 record_list_release (record_arch_list_tail); 1602 if (record_debug) 1603 fprintf_unfiltered (gdb_stdlog, 1604 "Process record: failed to record " 1605 "execution log."); 1606 return -1; 1607 } 1608 record_list->next = record_arch_list_head; 1609 record_arch_list_head->prev = record_list; 1610 record_list = record_arch_list_tail; 1611 1612 if (record_insn_num == record_insn_max_num && record_insn_max_num) 1613 record_list_release_first (); 1614 else 1615 record_insn_num++; 1616 } 1617 1618 return record_beneath_to_xfer_partial (record_beneath_to_xfer_partial_ops, 1619 object, annex, readbuf, writebuf, 1620 offset, len); 1621} 1622 1623/* Behavior is conditional on RECORD_IS_REPLAY. 1624 We will not actually insert or remove breakpoints when replaying, 1625 nor when recording. */ 1626 1627static int 1628record_insert_breakpoint (struct gdbarch *gdbarch, 1629 struct bp_target_info *bp_tgt) 1630{ 1631 if (!RECORD_IS_REPLAY) 1632 { 1633 struct cleanup *old_cleanups = record_gdb_operation_disable_set (); 1634 int ret = record_beneath_to_insert_breakpoint (gdbarch, bp_tgt); 1635 1636 do_cleanups (old_cleanups); 1637 1638 return ret; 1639 } 1640 1641 return 0; 1642} 1643 1644/* "to_remove_breakpoint" method for process record target. */ 1645 1646static int 1647record_remove_breakpoint (struct gdbarch *gdbarch, 1648 struct bp_target_info *bp_tgt) 1649{ 1650 if (!RECORD_IS_REPLAY) 1651 { 1652 struct cleanup *old_cleanups = record_gdb_operation_disable_set (); 1653 int ret = record_beneath_to_remove_breakpoint (gdbarch, bp_tgt); 1654 1655 do_cleanups (old_cleanups); 1656 1657 return ret; 1658 } 1659 1660 return 0; 1661} 1662 1663/* "to_can_execute_reverse" method for process record target. */ 1664 1665static int 1666record_can_execute_reverse (void) 1667{ 1668 return 1; 1669} 1670 1671/* "to_get_bookmark" method for process record and prec over core. */ 1672 1673static gdb_byte * 1674record_get_bookmark (char *args, int from_tty) 1675{ 1676 gdb_byte *ret = NULL; 1677 1678 /* Return stringified form of instruction count. */ 1679 if (record_list && record_list->type == record_end) 1680 ret = xstrdup (pulongest (record_list->u.end.insn_num)); 1681 1682 if (record_debug) 1683 { 1684 if (ret) 1685 fprintf_unfiltered (gdb_stdlog, 1686 "record_get_bookmark returns %s\n", ret); 1687 else 1688 fprintf_unfiltered (gdb_stdlog, 1689 "record_get_bookmark returns NULL\n"); 1690 } 1691 return ret; 1692} 1693 1694/* The implementation of the command "record goto". */ 1695static void cmd_record_goto (char *, int); 1696 1697/* "to_goto_bookmark" method for process record and prec over core. */ 1698 1699static void 1700record_goto_bookmark (gdb_byte *bookmark, int from_tty) 1701{ 1702 if (record_debug) 1703 fprintf_unfiltered (gdb_stdlog, 1704 "record_goto_bookmark receives %s\n", bookmark); 1705 1706 if (bookmark[0] == '\'' || bookmark[0] == '\"') 1707 { 1708 if (bookmark[strlen (bookmark) - 1] != bookmark[0]) 1709 error (_("Unbalanced quotes: %s"), bookmark); 1710 1711 /* Strip trailing quote. */ 1712 bookmark[strlen (bookmark) - 1] = '\0'; 1713 /* Strip leading quote. */ 1714 bookmark++; 1715 /* Pass along to cmd_record_goto. */ 1716 } 1717 1718 cmd_record_goto ((char *) bookmark, from_tty); 1719 return; 1720} 1721 1722static void 1723init_record_ops (void) 1724{ 1725 record_ops.to_shortname = "record"; 1726 record_ops.to_longname = "Process record and replay target"; 1727 record_ops.to_doc = 1728 "Log program while executing and replay execution from log."; 1729 record_ops.to_open = record_open; 1730 record_ops.to_close = record_close; 1731 record_ops.to_resume = record_resume; 1732 record_ops.to_wait = record_wait; 1733 record_ops.to_disconnect = record_disconnect; 1734 record_ops.to_detach = record_detach; 1735 record_ops.to_mourn_inferior = record_mourn_inferior; 1736 record_ops.to_kill = record_kill; 1737 record_ops.to_create_inferior = find_default_create_inferior; 1738 record_ops.to_store_registers = record_store_registers; 1739 record_ops.to_xfer_partial = record_xfer_partial; 1740 record_ops.to_insert_breakpoint = record_insert_breakpoint; 1741 record_ops.to_remove_breakpoint = record_remove_breakpoint; 1742 record_ops.to_stopped_by_watchpoint = record_stopped_by_watchpoint; 1743 record_ops.to_stopped_data_address = record_stopped_data_address; 1744 record_ops.to_can_execute_reverse = record_can_execute_reverse; 1745 record_ops.to_stratum = record_stratum; 1746 /* Add bookmark target methods. */ 1747 record_ops.to_get_bookmark = record_get_bookmark; 1748 record_ops.to_goto_bookmark = record_goto_bookmark; 1749 record_ops.to_magic = OPS_MAGIC; 1750} 1751 1752/* "to_resume" method for prec over corefile. */ 1753 1754static void 1755record_core_resume (struct target_ops *ops, ptid_t ptid, int step, 1756 enum target_signal signal) 1757{ 1758 record_resume_step = step; 1759} 1760 1761/* "to_kill" method for prec over corefile. */ 1762 1763static void 1764record_core_kill (struct target_ops *ops) 1765{ 1766 if (record_debug) 1767 fprintf_unfiltered (gdb_stdlog, "Process record: record_core_kill\n"); 1768 1769 unpush_target (&record_core_ops); 1770} 1771 1772/* "to_fetch_registers" method for prec over corefile. */ 1773 1774static void 1775record_core_fetch_registers (struct target_ops *ops, 1776 struct regcache *regcache, 1777 int regno) 1778{ 1779 if (regno < 0) 1780 { 1781 int num = gdbarch_num_regs (get_regcache_arch (regcache)); 1782 int i; 1783 1784 for (i = 0; i < num; i ++) 1785 regcache_raw_supply (regcache, i, 1786 record_core_regbuf + MAX_REGISTER_SIZE * i); 1787 } 1788 else 1789 regcache_raw_supply (regcache, regno, 1790 record_core_regbuf + MAX_REGISTER_SIZE * regno); 1791} 1792 1793/* "to_prepare_to_store" method for prec over corefile. */ 1794 1795static void 1796record_core_prepare_to_store (struct regcache *regcache) 1797{ 1798} 1799 1800/* "to_store_registers" method for prec over corefile. */ 1801 1802static void 1803record_core_store_registers (struct target_ops *ops, 1804 struct regcache *regcache, 1805 int regno) 1806{ 1807 if (record_gdb_operation_disable) 1808 regcache_raw_collect (regcache, regno, 1809 record_core_regbuf + MAX_REGISTER_SIZE * regno); 1810 else 1811 error (_("You can't do that without a process to debug.")); 1812} 1813 1814/* "to_xfer_partial" method for prec over corefile. */ 1815 1816static LONGEST 1817record_core_xfer_partial (struct target_ops *ops, enum target_object object, 1818 const char *annex, gdb_byte *readbuf, 1819 const gdb_byte *writebuf, ULONGEST offset, 1820 LONGEST len) 1821{ 1822 if (object == TARGET_OBJECT_MEMORY) 1823 { 1824 if (record_gdb_operation_disable || !writebuf) 1825 { 1826 struct target_section *p; 1827 1828 for (p = record_core_start; p < record_core_end; p++) 1829 { 1830 if (offset >= p->addr) 1831 { 1832 struct record_core_buf_entry *entry; 1833 ULONGEST sec_offset; 1834 1835 if (offset >= p->endaddr) 1836 continue; 1837 1838 if (offset + len > p->endaddr) 1839 len = p->endaddr - offset; 1840 1841 sec_offset = offset - p->addr; 1842 1843 /* Read readbuf or write writebuf p, offset, len. */ 1844 /* Check flags. */ 1845 if (p->the_bfd_section->flags & SEC_CONSTRUCTOR 1846 || (p->the_bfd_section->flags & SEC_HAS_CONTENTS) == 0) 1847 { 1848 if (readbuf) 1849 memset (readbuf, 0, len); 1850 return len; 1851 } 1852 /* Get record_core_buf_entry. */ 1853 for (entry = record_core_buf_list; entry; 1854 entry = entry->prev) 1855 if (entry->p == p) 1856 break; 1857 if (writebuf) 1858 { 1859 if (!entry) 1860 { 1861 /* Add a new entry. */ 1862 entry = (struct record_core_buf_entry *) 1863 xmalloc (sizeof (struct record_core_buf_entry)); 1864 entry->p = p; 1865 if (!bfd_malloc_and_get_section (p->bfd, 1866 p->the_bfd_section, 1867 &entry->buf)) 1868 { 1869 xfree (entry); 1870 return 0; 1871 } 1872 entry->prev = record_core_buf_list; 1873 record_core_buf_list = entry; 1874 } 1875 1876 memcpy (entry->buf + sec_offset, writebuf, 1877 (size_t) len); 1878 } 1879 else 1880 { 1881 if (!entry) 1882 return record_beneath_to_xfer_partial 1883 (record_beneath_to_xfer_partial_ops, 1884 object, annex, readbuf, writebuf, 1885 offset, len); 1886 1887 memcpy (readbuf, entry->buf + sec_offset, 1888 (size_t) len); 1889 } 1890 1891 return len; 1892 } 1893 } 1894 1895 return -1; 1896 } 1897 else 1898 error (_("You can't do that without a process to debug.")); 1899 } 1900 1901 return record_beneath_to_xfer_partial (record_beneath_to_xfer_partial_ops, 1902 object, annex, readbuf, writebuf, 1903 offset, len); 1904} 1905 1906/* "to_insert_breakpoint" method for prec over corefile. */ 1907 1908static int 1909record_core_insert_breakpoint (struct gdbarch *gdbarch, 1910 struct bp_target_info *bp_tgt) 1911{ 1912 return 0; 1913} 1914 1915/* "to_remove_breakpoint" method for prec over corefile. */ 1916 1917static int 1918record_core_remove_breakpoint (struct gdbarch *gdbarch, 1919 struct bp_target_info *bp_tgt) 1920{ 1921 return 0; 1922} 1923 1924/* "to_has_execution" method for prec over corefile. */ 1925 1926static int 1927record_core_has_execution (struct target_ops *ops, ptid_t the_ptid) 1928{ 1929 return 1; 1930} 1931 1932static void 1933init_record_core_ops (void) 1934{ 1935 record_core_ops.to_shortname = "record-core"; 1936 record_core_ops.to_longname = "Process record and replay target"; 1937 record_core_ops.to_doc = 1938 "Log program while executing and replay execution from log."; 1939 record_core_ops.to_open = record_open; 1940 record_core_ops.to_close = record_close; 1941 record_core_ops.to_resume = record_core_resume; 1942 record_core_ops.to_wait = record_wait; 1943 record_core_ops.to_kill = record_core_kill; 1944 record_core_ops.to_fetch_registers = record_core_fetch_registers; 1945 record_core_ops.to_prepare_to_store = record_core_prepare_to_store; 1946 record_core_ops.to_store_registers = record_core_store_registers; 1947 record_core_ops.to_xfer_partial = record_core_xfer_partial; 1948 record_core_ops.to_insert_breakpoint = record_core_insert_breakpoint; 1949 record_core_ops.to_remove_breakpoint = record_core_remove_breakpoint; 1950 record_core_ops.to_stopped_by_watchpoint = record_stopped_by_watchpoint; 1951 record_core_ops.to_stopped_data_address = record_stopped_data_address; 1952 record_core_ops.to_can_execute_reverse = record_can_execute_reverse; 1953 record_core_ops.to_has_execution = record_core_has_execution; 1954 record_core_ops.to_stratum = record_stratum; 1955 /* Add bookmark target methods. */ 1956 record_core_ops.to_get_bookmark = record_get_bookmark; 1957 record_core_ops.to_goto_bookmark = record_goto_bookmark; 1958 record_core_ops.to_magic = OPS_MAGIC; 1959} 1960 1961/* Implement "show record debug" command. */ 1962 1963static void 1964show_record_debug (struct ui_file *file, int from_tty, 1965 struct cmd_list_element *c, const char *value) 1966{ 1967 fprintf_filtered (file, _("Debugging of process record target is %s.\n"), 1968 value); 1969} 1970 1971/* Alias for "target record". */ 1972 1973static void 1974cmd_record_start (char *args, int from_tty) 1975{ 1976 execute_command ("target record", from_tty); 1977} 1978 1979/* Truncate the record log from the present point 1980 of replay until the end. */ 1981 1982static void 1983cmd_record_delete (char *args, int from_tty) 1984{ 1985 if (current_target.to_stratum == record_stratum) 1986 { 1987 if (RECORD_IS_REPLAY) 1988 { 1989 if (!from_tty || query (_("Delete the log from this point forward " 1990 "and begin to record the running message " 1991 "at current PC?"))) 1992 record_list_release_following (record_list); 1993 } 1994 else 1995 printf_unfiltered (_("Already at end of record list.\n")); 1996 1997 } 1998 else 1999 printf_unfiltered (_("Process record is not started.\n")); 2000} 2001 2002/* Implement the "stoprecord" or "record stop" command. */ 2003 2004static void 2005cmd_record_stop (char *args, int from_tty) 2006{ 2007 if (current_target.to_stratum == record_stratum) 2008 { 2009 unpush_target (&record_ops); 2010 printf_unfiltered (_("Process record is stopped and all execution " 2011 "logs are deleted.\n")); 2012 } 2013 else 2014 printf_unfiltered (_("Process record is not started.\n")); 2015} 2016 2017/* Set upper limit of record log size. */ 2018 2019static void 2020set_record_insn_max_num (char *args, int from_tty, struct cmd_list_element *c) 2021{ 2022 if (record_insn_num > record_insn_max_num && record_insn_max_num) 2023 { 2024 /* Count down record_insn_num while releasing records from list. */ 2025 while (record_insn_num > record_insn_max_num) 2026 { 2027 record_list_release_first (); 2028 record_insn_num--; 2029 } 2030 } 2031} 2032 2033static struct cmd_list_element *record_cmdlist, *set_record_cmdlist, 2034 *show_record_cmdlist, *info_record_cmdlist; 2035 2036static void 2037set_record_command (char *args, int from_tty) 2038{ 2039 printf_unfiltered (_("\"set record\" must be followed " 2040 "by an apporpriate subcommand.\n")); 2041 help_list (set_record_cmdlist, "set record ", all_commands, gdb_stdout); 2042} 2043 2044static void 2045show_record_command (char *args, int from_tty) 2046{ 2047 cmd_show_list (show_record_cmdlist, from_tty, ""); 2048} 2049 2050/* Display some statistics about the execution log. */ 2051 2052static void 2053info_record_command (char *args, int from_tty) 2054{ 2055 struct record_entry *p; 2056 2057 if (current_target.to_stratum == record_stratum) 2058 { 2059 if (RECORD_IS_REPLAY) 2060 printf_filtered (_("Replay mode:\n")); 2061 else 2062 printf_filtered (_("Record mode:\n")); 2063 2064 /* Find entry for first actual instruction in the log. */ 2065 for (p = record_first.next; 2066 p != NULL && p->type != record_end; 2067 p = p->next) 2068 ; 2069 2070 /* Do we have a log at all? */ 2071 if (p != NULL && p->type == record_end) 2072 { 2073 /* Display instruction number for first instruction in the log. */ 2074 printf_filtered (_("Lowest recorded instruction number is %s.\n"), 2075 pulongest (p->u.end.insn_num)); 2076 2077 /* If in replay mode, display where we are in the log. */ 2078 if (RECORD_IS_REPLAY) 2079 printf_filtered (_("Current instruction number is %s.\n"), 2080 pulongest (record_list->u.end.insn_num)); 2081 2082 /* Display instruction number for last instruction in the log. */ 2083 printf_filtered (_("Highest recorded instruction number is %s.\n"), 2084 pulongest (record_insn_count)); 2085 2086 /* Display log count. */ 2087 printf_filtered (_("Log contains %d instructions.\n"), 2088 record_insn_num); 2089 } 2090 else 2091 { 2092 printf_filtered (_("No instructions have been logged.\n")); 2093 } 2094 } 2095 else 2096 { 2097 printf_filtered (_("target record is not active.\n")); 2098 } 2099 2100 /* Display max log size. */ 2101 printf_filtered (_("Max logged instructions is %d.\n"), 2102 record_insn_max_num); 2103} 2104 2105/* Record log save-file format 2106 Version 1 (never released) 2107 2108 Header: 2109 4 bytes: magic number htonl(0x20090829). 2110 NOTE: be sure to change whenever this file format changes! 2111 2112 Records: 2113 record_end: 2114 1 byte: record type (record_end, see enum record_type). 2115 record_reg: 2116 1 byte: record type (record_reg, see enum record_type). 2117 8 bytes: register id (network byte order). 2118 MAX_REGISTER_SIZE bytes: register value. 2119 record_mem: 2120 1 byte: record type (record_mem, see enum record_type). 2121 8 bytes: memory length (network byte order). 2122 8 bytes: memory address (network byte order). 2123 n bytes: memory value (n == memory length). 2124 2125 Version 2 2126 4 bytes: magic number netorder32(0x20091016). 2127 NOTE: be sure to change whenever this file format changes! 2128 2129 Records: 2130 record_end: 2131 1 byte: record type (record_end, see enum record_type). 2132 4 bytes: signal 2133 4 bytes: instruction count 2134 record_reg: 2135 1 byte: record type (record_reg, see enum record_type). 2136 4 bytes: register id (network byte order). 2137 n bytes: register value (n == actual register size). 2138 (eg. 4 bytes for x86 general registers). 2139 record_mem: 2140 1 byte: record type (record_mem, see enum record_type). 2141 4 bytes: memory length (network byte order). 2142 8 bytes: memory address (network byte order). 2143 n bytes: memory value (n == memory length). 2144 2145*/ 2146 2147/* bfdcore_read -- read bytes from a core file section. */ 2148 2149static inline void 2150bfdcore_read (bfd *obfd, asection *osec, void *buf, int len, int *offset) 2151{ 2152 int ret = bfd_get_section_contents (obfd, osec, buf, *offset, len); 2153 2154 if (ret) 2155 *offset += len; 2156 else 2157 error (_("Failed to read %d bytes from core file %s ('%s')."), 2158 len, bfd_get_filename (obfd), 2159 bfd_errmsg (bfd_get_error ())); 2160} 2161 2162static inline uint64_t 2163netorder64 (uint64_t input) 2164{ 2165 uint64_t ret; 2166 2167 store_unsigned_integer ((gdb_byte *) &ret, sizeof (ret), 2168 BFD_ENDIAN_BIG, input); 2169 return ret; 2170} 2171 2172static inline uint32_t 2173netorder32 (uint32_t input) 2174{ 2175 uint32_t ret; 2176 2177 store_unsigned_integer ((gdb_byte *) &ret, sizeof (ret), 2178 BFD_ENDIAN_BIG, input); 2179 return ret; 2180} 2181 2182static inline uint16_t 2183netorder16 (uint16_t input) 2184{ 2185 uint16_t ret; 2186 2187 store_unsigned_integer ((gdb_byte *) &ret, sizeof (ret), 2188 BFD_ENDIAN_BIG, input); 2189 return ret; 2190} 2191 2192/* Restore the execution log from a core_bfd file. */ 2193static void 2194record_restore (void) 2195{ 2196 uint32_t magic; 2197 struct cleanup *old_cleanups; 2198 struct record_entry *rec; 2199 asection *osec; 2200 uint32_t osec_size; 2201 int bfd_offset = 0; 2202 struct regcache *regcache; 2203 2204 /* We restore the execution log from the open core bfd, 2205 if there is one. */ 2206 if (core_bfd == NULL) 2207 return; 2208 2209 /* "record_restore" can only be called when record list is empty. */ 2210 gdb_assert (record_first.next == NULL); 2211 2212 if (record_debug) 2213 fprintf_unfiltered (gdb_stdlog, "Restoring recording from core file.\n"); 2214 2215 /* Now need to find our special note section. */ 2216 osec = bfd_get_section_by_name (core_bfd, "null0"); 2217 if (record_debug) 2218 fprintf_unfiltered (gdb_stdlog, "Find precord section %s.\n", 2219 osec ? "succeeded" : "failed"); 2220 if (osec == NULL) 2221 return; 2222 osec_size = bfd_section_size (core_bfd, osec); 2223 if (record_debug) 2224 fprintf_unfiltered (gdb_stdlog, "%s", bfd_section_name (core_bfd, osec)); 2225 2226 /* Check the magic code. */ 2227 bfdcore_read (core_bfd, osec, &magic, sizeof (magic), &bfd_offset); 2228 if (magic != RECORD_FILE_MAGIC) 2229 error (_("Version mis-match or file format error in core file %s."), 2230 bfd_get_filename (core_bfd)); 2231 if (record_debug) 2232 fprintf_unfiltered (gdb_stdlog, 2233 " Reading 4-byte magic cookie " 2234 "RECORD_FILE_MAGIC (0x%s)\n", 2235 phex_nz (netorder32 (magic), 4)); 2236 2237 /* Restore the entries in recfd into record_arch_list_head and 2238 record_arch_list_tail. */ 2239 record_arch_list_head = NULL; 2240 record_arch_list_tail = NULL; 2241 record_insn_num = 0; 2242 old_cleanups = make_cleanup (record_arch_list_cleanups, 0); 2243 regcache = get_current_regcache (); 2244 2245 while (1) 2246 { 2247 uint8_t rectype; 2248 uint32_t regnum, len, signal, count; 2249 uint64_t addr; 2250 2251 /* We are finished when offset reaches osec_size. */ 2252 if (bfd_offset >= osec_size) 2253 break; 2254 bfdcore_read (core_bfd, osec, &rectype, sizeof (rectype), &bfd_offset); 2255 2256 switch (rectype) 2257 { 2258 case record_reg: /* reg */ 2259 /* Get register number to regnum. */ 2260 bfdcore_read (core_bfd, osec, ®num, 2261 sizeof (regnum), &bfd_offset); 2262 regnum = netorder32 (regnum); 2263 2264 rec = record_reg_alloc (regcache, regnum); 2265 2266 /* Get val. */ 2267 bfdcore_read (core_bfd, osec, record_get_loc (rec), 2268 rec->u.reg.len, &bfd_offset); 2269 2270 if (record_debug) 2271 fprintf_unfiltered (gdb_stdlog, 2272 " Reading register %d (1 " 2273 "plus %lu plus %d bytes)\n", 2274 rec->u.reg.num, 2275 (unsigned long) sizeof (regnum), 2276 rec->u.reg.len); 2277 break; 2278 2279 case record_mem: /* mem */ 2280 /* Get len. */ 2281 bfdcore_read (core_bfd, osec, &len, 2282 sizeof (len), &bfd_offset); 2283 len = netorder32 (len); 2284 2285 /* Get addr. */ 2286 bfdcore_read (core_bfd, osec, &addr, 2287 sizeof (addr), &bfd_offset); 2288 addr = netorder64 (addr); 2289 2290 rec = record_mem_alloc (addr, len); 2291 2292 /* Get val. */ 2293 bfdcore_read (core_bfd, osec, record_get_loc (rec), 2294 rec->u.mem.len, &bfd_offset); 2295 2296 if (record_debug) 2297 fprintf_unfiltered (gdb_stdlog, 2298 " Reading memory %s (1 plus " 2299 "%lu plus %lu plus %d bytes)\n", 2300 paddress (get_current_arch (), 2301 rec->u.mem.addr), 2302 (unsigned long) sizeof (addr), 2303 (unsigned long) sizeof (len), 2304 rec->u.mem.len); 2305 break; 2306 2307 case record_end: /* end */ 2308 rec = record_end_alloc (); 2309 record_insn_num ++; 2310 2311 /* Get signal value. */ 2312 bfdcore_read (core_bfd, osec, &signal, 2313 sizeof (signal), &bfd_offset); 2314 signal = netorder32 (signal); 2315 rec->u.end.sigval = signal; 2316 2317 /* Get insn count. */ 2318 bfdcore_read (core_bfd, osec, &count, 2319 sizeof (count), &bfd_offset); 2320 count = netorder32 (count); 2321 rec->u.end.insn_num = count; 2322 record_insn_count = count + 1; 2323 if (record_debug) 2324 fprintf_unfiltered (gdb_stdlog, 2325 " Reading record_end (1 + " 2326 "%lu + %lu bytes), offset == %s\n", 2327 (unsigned long) sizeof (signal), 2328 (unsigned long) sizeof (count), 2329 paddress (get_current_arch (), 2330 bfd_offset)); 2331 break; 2332 2333 default: 2334 error (_("Bad entry type in core file %s."), 2335 bfd_get_filename (core_bfd)); 2336 break; 2337 } 2338 2339 /* Add rec to record arch list. */ 2340 record_arch_list_add (rec); 2341 } 2342 2343 discard_cleanups (old_cleanups); 2344 2345 /* Add record_arch_list_head to the end of record list. */ 2346 record_first.next = record_arch_list_head; 2347 record_arch_list_head->prev = &record_first; 2348 record_arch_list_tail->next = NULL; 2349 record_list = &record_first; 2350 2351 /* Update record_insn_max_num. */ 2352 if (record_insn_num > record_insn_max_num) 2353 { 2354 record_insn_max_num = record_insn_num; 2355 warning (_("Auto increase record/replay buffer limit to %d."), 2356 record_insn_max_num); 2357 } 2358 2359 /* Succeeded. */ 2360 printf_filtered (_("Restored records from core file %s.\n"), 2361 bfd_get_filename (core_bfd)); 2362 2363 print_stack_frame (get_selected_frame (NULL), 1, SRC_AND_LOC); 2364} 2365 2366/* bfdcore_write -- write bytes into a core file section. */ 2367 2368static inline void 2369bfdcore_write (bfd *obfd, asection *osec, void *buf, int len, int *offset) 2370{ 2371 int ret = bfd_set_section_contents (obfd, osec, buf, *offset, len); 2372 2373 if (ret) 2374 *offset += len; 2375 else 2376 error (_("Failed to write %d bytes to core file %s ('%s')."), 2377 len, bfd_get_filename (obfd), 2378 bfd_errmsg (bfd_get_error ())); 2379} 2380 2381/* Restore the execution log from a file. We use a modified elf 2382 corefile format, with an extra section for our data. */ 2383 2384static void 2385cmd_record_restore (char *args, int from_tty) 2386{ 2387 core_file_command (args, from_tty); 2388 record_open (args, from_tty); 2389} 2390 2391static void 2392record_save_cleanups (void *data) 2393{ 2394 bfd *obfd = data; 2395 char *pathname = xstrdup (bfd_get_filename (obfd)); 2396 2397 bfd_close (obfd); 2398 unlink (pathname); 2399 xfree (pathname); 2400} 2401 2402/* Save the execution log to a file. We use a modified elf corefile 2403 format, with an extra section for our data. */ 2404 2405static void 2406cmd_record_save (char *args, int from_tty) 2407{ 2408 char *recfilename, recfilename_buffer[40]; 2409 struct record_entry *cur_record_list; 2410 uint32_t magic; 2411 struct regcache *regcache; 2412 struct gdbarch *gdbarch; 2413 struct cleanup *old_cleanups; 2414 struct cleanup *set_cleanups; 2415 bfd *obfd; 2416 int save_size = 0; 2417 asection *osec = NULL; 2418 int bfd_offset = 0; 2419 2420 if (strcmp (current_target.to_shortname, "record") != 0) 2421 error (_("This command can only be used with target 'record'.\n" 2422 "Use 'target record' first.\n")); 2423 2424 if (args && *args) 2425 recfilename = args; 2426 else 2427 { 2428 /* Default recfile name is "gdb_record.PID". */ 2429 snprintf (recfilename_buffer, sizeof (recfilename_buffer), 2430 "gdb_record.%d", PIDGET (inferior_ptid)); 2431 recfilename = recfilename_buffer; 2432 } 2433 2434 /* Open the save file. */ 2435 if (record_debug) 2436 fprintf_unfiltered (gdb_stdlog, "Saving execution log to core file '%s'\n", 2437 recfilename); 2438 2439 /* Open the output file. */ 2440 obfd = create_gcore_bfd (recfilename); 2441 old_cleanups = make_cleanup (record_save_cleanups, obfd); 2442 2443 /* Save the current record entry to "cur_record_list". */ 2444 cur_record_list = record_list; 2445 2446 /* Get the values of regcache and gdbarch. */ 2447 regcache = get_current_regcache (); 2448 gdbarch = get_regcache_arch (regcache); 2449 2450 /* Disable the GDB operation record. */ 2451 set_cleanups = record_gdb_operation_disable_set (); 2452 2453 /* Reverse execute to the begin of record list. */ 2454 while (1) 2455 { 2456 /* Check for beginning and end of log. */ 2457 if (record_list == &record_first) 2458 break; 2459 2460 record_exec_insn (regcache, gdbarch, record_list); 2461 2462 if (record_list->prev) 2463 record_list = record_list->prev; 2464 } 2465 2466 /* Compute the size needed for the extra bfd section. */ 2467 save_size = 4; /* magic cookie */ 2468 for (record_list = record_first.next; record_list; 2469 record_list = record_list->next) 2470 switch (record_list->type) 2471 { 2472 case record_end: 2473 save_size += 1 + 4 + 4; 2474 break; 2475 case record_reg: 2476 save_size += 1 + 4 + record_list->u.reg.len; 2477 break; 2478 case record_mem: 2479 save_size += 1 + 4 + 8 + record_list->u.mem.len; 2480 break; 2481 } 2482 2483 /* Make the new bfd section. */ 2484 osec = bfd_make_section_anyway_with_flags (obfd, "precord", 2485 SEC_HAS_CONTENTS 2486 | SEC_READONLY); 2487 if (osec == NULL) 2488 error (_("Failed to create 'precord' section for corefile %s: %s"), 2489 recfilename, 2490 bfd_errmsg (bfd_get_error ())); 2491 bfd_set_section_size (obfd, osec, save_size); 2492 bfd_set_section_vma (obfd, osec, 0); 2493 bfd_set_section_alignment (obfd, osec, 0); 2494 bfd_section_lma (obfd, osec) = 0; 2495 2496 /* Save corefile state. */ 2497 write_gcore_file (obfd); 2498 2499 /* Write out the record log. */ 2500 /* Write the magic code. */ 2501 magic = RECORD_FILE_MAGIC; 2502 if (record_debug) 2503 fprintf_unfiltered (gdb_stdlog, 2504 " Writing 4-byte magic cookie " 2505 "RECORD_FILE_MAGIC (0x%s)\n", 2506 phex_nz (magic, 4)); 2507 bfdcore_write (obfd, osec, &magic, sizeof (magic), &bfd_offset); 2508 2509 /* Save the entries to recfd and forward execute to the end of 2510 record list. */ 2511 record_list = &record_first; 2512 while (1) 2513 { 2514 /* Save entry. */ 2515 if (record_list != &record_first) 2516 { 2517 uint8_t type; 2518 uint32_t regnum, len, signal, count; 2519 uint64_t addr; 2520 2521 type = record_list->type; 2522 bfdcore_write (obfd, osec, &type, sizeof (type), &bfd_offset); 2523 2524 switch (record_list->type) 2525 { 2526 case record_reg: /* reg */ 2527 if (record_debug) 2528 fprintf_unfiltered (gdb_stdlog, 2529 " Writing register %d (1 " 2530 "plus %lu plus %d bytes)\n", 2531 record_list->u.reg.num, 2532 (unsigned long) sizeof (regnum), 2533 record_list->u.reg.len); 2534 2535 /* Write regnum. */ 2536 regnum = netorder32 (record_list->u.reg.num); 2537 bfdcore_write (obfd, osec, ®num, 2538 sizeof (regnum), &bfd_offset); 2539 2540 /* Write regval. */ 2541 bfdcore_write (obfd, osec, record_get_loc (record_list), 2542 record_list->u.reg.len, &bfd_offset); 2543 break; 2544 2545 case record_mem: /* mem */ 2546 if (record_debug) 2547 fprintf_unfiltered (gdb_stdlog, 2548 " Writing memory %s (1 plus " 2549 "%lu plus %lu plus %d bytes)\n", 2550 paddress (gdbarch, 2551 record_list->u.mem.addr), 2552 (unsigned long) sizeof (addr), 2553 (unsigned long) sizeof (len), 2554 record_list->u.mem.len); 2555 2556 /* Write memlen. */ 2557 len = netorder32 (record_list->u.mem.len); 2558 bfdcore_write (obfd, osec, &len, sizeof (len), &bfd_offset); 2559 2560 /* Write memaddr. */ 2561 addr = netorder64 (record_list->u.mem.addr); 2562 bfdcore_write (obfd, osec, &addr, 2563 sizeof (addr), &bfd_offset); 2564 2565 /* Write memval. */ 2566 bfdcore_write (obfd, osec, record_get_loc (record_list), 2567 record_list->u.mem.len, &bfd_offset); 2568 break; 2569 2570 case record_end: 2571 if (record_debug) 2572 fprintf_unfiltered (gdb_stdlog, 2573 " Writing record_end (1 + " 2574 "%lu + %lu bytes)\n", 2575 (unsigned long) sizeof (signal), 2576 (unsigned long) sizeof (count)); 2577 /* Write signal value. */ 2578 signal = netorder32 (record_list->u.end.sigval); 2579 bfdcore_write (obfd, osec, &signal, 2580 sizeof (signal), &bfd_offset); 2581 2582 /* Write insn count. */ 2583 count = netorder32 (record_list->u.end.insn_num); 2584 bfdcore_write (obfd, osec, &count, 2585 sizeof (count), &bfd_offset); 2586 break; 2587 } 2588 } 2589 2590 /* Execute entry. */ 2591 record_exec_insn (regcache, gdbarch, record_list); 2592 2593 if (record_list->next) 2594 record_list = record_list->next; 2595 else 2596 break; 2597 } 2598 2599 /* Reverse execute to cur_record_list. */ 2600 while (1) 2601 { 2602 /* Check for beginning and end of log. */ 2603 if (record_list == cur_record_list) 2604 break; 2605 2606 record_exec_insn (regcache, gdbarch, record_list); 2607 2608 if (record_list->prev) 2609 record_list = record_list->prev; 2610 } 2611 2612 do_cleanups (set_cleanups); 2613 bfd_close (obfd); 2614 discard_cleanups (old_cleanups); 2615 2616 /* Succeeded. */ 2617 printf_filtered (_("Saved core file %s with execution log.\n"), 2618 recfilename); 2619} 2620 2621/* record_goto_insn -- rewind the record log (forward or backward, 2622 depending on DIR) to the given entry, changing the program state 2623 correspondingly. */ 2624 2625static void 2626record_goto_insn (struct record_entry *entry, 2627 enum exec_direction_kind dir) 2628{ 2629 struct cleanup *set_cleanups = record_gdb_operation_disable_set (); 2630 struct regcache *regcache = get_current_regcache (); 2631 struct gdbarch *gdbarch = get_regcache_arch (regcache); 2632 2633 /* Assume everything is valid: we will hit the entry, 2634 and we will not hit the end of the recording. */ 2635 2636 if (dir == EXEC_FORWARD) 2637 record_list = record_list->next; 2638 2639 do 2640 { 2641 record_exec_insn (regcache, gdbarch, record_list); 2642 if (dir == EXEC_REVERSE) 2643 record_list = record_list->prev; 2644 else 2645 record_list = record_list->next; 2646 } while (record_list != entry); 2647 do_cleanups (set_cleanups); 2648} 2649 2650/* "record goto" command. Argument is an instruction number, 2651 as given by "info record". 2652 2653 Rewinds the recording (forward or backward) to the given instruction. */ 2654 2655static void 2656cmd_record_goto (char *arg, int from_tty) 2657{ 2658 struct record_entry *p = NULL; 2659 ULONGEST target_insn = 0; 2660 2661 if (arg == NULL || *arg == '\0') 2662 error (_("Command requires an argument (insn number to go to).")); 2663 2664 if (strncmp (arg, "start", strlen ("start")) == 0 2665 || strncmp (arg, "begin", strlen ("begin")) == 0) 2666 { 2667 /* Special case. Find first insn. */ 2668 for (p = &record_first; p != NULL; p = p->next) 2669 if (p->type == record_end) 2670 break; 2671 if (p) 2672 target_insn = p->u.end.insn_num; 2673 } 2674 else if (strncmp (arg, "end", strlen ("end")) == 0) 2675 { 2676 /* Special case. Find last insn. */ 2677 for (p = record_list; p->next != NULL; p = p->next) 2678 ; 2679 for (; p!= NULL; p = p->prev) 2680 if (p->type == record_end) 2681 break; 2682 if (p) 2683 target_insn = p->u.end.insn_num; 2684 } 2685 else 2686 { 2687 /* General case. Find designated insn. */ 2688 target_insn = parse_and_eval_long (arg); 2689 2690 for (p = &record_first; p != NULL; p = p->next) 2691 if (p->type == record_end && p->u.end.insn_num == target_insn) 2692 break; 2693 } 2694 2695 if (p == NULL) 2696 error (_("Target insn '%s' not found."), arg); 2697 else if (p == record_list) 2698 error (_("Already at insn '%s'."), arg); 2699 else if (p->u.end.insn_num > record_list->u.end.insn_num) 2700 { 2701 printf_filtered (_("Go forward to insn number %s\n"), 2702 pulongest (target_insn)); 2703 record_goto_insn (p, EXEC_FORWARD); 2704 } 2705 else 2706 { 2707 printf_filtered (_("Go backward to insn number %s\n"), 2708 pulongest (target_insn)); 2709 record_goto_insn (p, EXEC_REVERSE); 2710 } 2711 registers_changed (); 2712 reinit_frame_cache (); 2713 print_stack_frame (get_selected_frame (NULL), 1, SRC_AND_LOC); 2714} 2715 2716void 2717_initialize_record (void) 2718{ 2719 struct cmd_list_element *c; 2720 2721 /* Init record_first. */ 2722 record_first.prev = NULL; 2723 record_first.next = NULL; 2724 record_first.type = record_end; 2725 2726 init_record_ops (); 2727 add_target (&record_ops); 2728 init_record_core_ops (); 2729 add_target (&record_core_ops); 2730 2731 add_setshow_zinteger_cmd ("record", no_class, &record_debug, 2732 _("Set debugging of record/replay feature."), 2733 _("Show debugging of record/replay feature."), 2734 _("When enabled, debugging output for " 2735 "record/replay feature is displayed."), 2736 NULL, show_record_debug, &setdebuglist, 2737 &showdebuglist); 2738 2739 c = add_prefix_cmd ("record", class_obscure, cmd_record_start, 2740 _("Abbreviated form of \"target record\" command."), 2741 &record_cmdlist, "record ", 0, &cmdlist); 2742 set_cmd_completer (c, filename_completer); 2743 2744 add_com_alias ("rec", "record", class_obscure, 1); 2745 add_prefix_cmd ("record", class_support, set_record_command, 2746 _("Set record options"), &set_record_cmdlist, 2747 "set record ", 0, &setlist); 2748 add_alias_cmd ("rec", "record", class_obscure, 1, &setlist); 2749 add_prefix_cmd ("record", class_support, show_record_command, 2750 _("Show record options"), &show_record_cmdlist, 2751 "show record ", 0, &showlist); 2752 add_alias_cmd ("rec", "record", class_obscure, 1, &showlist); 2753 add_prefix_cmd ("record", class_support, info_record_command, 2754 _("Info record options"), &info_record_cmdlist, 2755 "info record ", 0, &infolist); 2756 add_alias_cmd ("rec", "record", class_obscure, 1, &infolist); 2757 2758 c = add_cmd ("save", class_obscure, cmd_record_save, 2759 _("Save the execution log to a file.\n\ 2760Argument is optional filename.\n\ 2761Default filename is 'gdb_record.<process_id>'."), 2762 &record_cmdlist); 2763 set_cmd_completer (c, filename_completer); 2764 2765 c = add_cmd ("restore", class_obscure, cmd_record_restore, 2766 _("Restore the execution log from a file.\n\ 2767Argument is filename. File must be created with 'record save'."), 2768 &record_cmdlist); 2769 set_cmd_completer (c, filename_completer); 2770 2771 add_cmd ("delete", class_obscure, cmd_record_delete, 2772 _("Delete the rest of execution log and start recording it anew."), 2773 &record_cmdlist); 2774 add_alias_cmd ("d", "delete", class_obscure, 1, &record_cmdlist); 2775 add_alias_cmd ("del", "delete", class_obscure, 1, &record_cmdlist); 2776 2777 add_cmd ("stop", class_obscure, cmd_record_stop, 2778 _("Stop the record/replay target."), 2779 &record_cmdlist); 2780 add_alias_cmd ("s", "stop", class_obscure, 1, &record_cmdlist); 2781 2782 /* Record instructions number limit command. */ 2783 add_setshow_boolean_cmd ("stop-at-limit", no_class, 2784 &record_stop_at_limit, _("\ 2785Set whether record/replay stops when record/replay buffer becomes full."), _("\ 2786Show whether record/replay stops when record/replay buffer becomes full."), 2787 _("Default is ON.\n\ 2788When ON, if the record/replay buffer becomes full, ask user what to do.\n\ 2789When OFF, if the record/replay buffer becomes full,\n\ 2790delete the oldest recorded instruction to make room for each new one."), 2791 NULL, NULL, 2792 &set_record_cmdlist, &show_record_cmdlist); 2793 add_setshow_uinteger_cmd ("insn-number-max", no_class, 2794 &record_insn_max_num, 2795 _("Set record/replay buffer limit."), 2796 _("Show record/replay buffer limit."), _("\ 2797Set the maximum number of instructions to be stored in the\n\ 2798record/replay buffer. Zero means unlimited. Default is 200000."), 2799 set_record_insn_max_num, 2800 NULL, &set_record_cmdlist, &show_record_cmdlist); 2801 2802 add_cmd ("goto", class_obscure, cmd_record_goto, _("\ 2803Restore the program to its state at instruction number N.\n\ 2804Argument is instruction number, as shown by 'info record'."), 2805 &record_cmdlist); 2806 2807 add_setshow_boolean_cmd ("memory-query", no_class, 2808 &record_memory_query, _("\ 2809Set whether query if PREC cannot record memory change of next instruction."), 2810 _("\ 2811Show whether query if PREC cannot record memory change of next instruction."), 2812 _("\ 2813Default is OFF.\n\ 2814When ON, query if PREC cannot record memory change of next instruction."), 2815 NULL, NULL, 2816 &set_record_cmdlist, &show_record_cmdlist); 2817 2818} 2819