| 1 | /* Reverse execution and reverse debugging. |
| 2 | |
| 3 | Copyright (C) 2006-2016 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 "target.h" |
| 22 | #include "top.h" |
| 23 | #include "cli/cli-cmds.h" |
| 24 | #include "cli/cli-decode.h" |
| 25 | #include "cli/cli-utils.h" |
| 26 | #include "inferior.h" |
| 27 | #include "infrun.h" |
| 28 | #include "regcache.h" |
| 29 | |
| 30 | /* User interface: |
| 31 | reverse-step, reverse-next etc. */ |
| 32 | |
| 33 | static void |
| 34 | exec_direction_default (void *notused) |
| 35 | { |
| 36 | /* Return execution direction to default state. */ |
| 37 | execution_direction = EXEC_FORWARD; |
| 38 | } |
| 39 | |
| 40 | /* exec_reverse_once -- accepts an arbitrary gdb command (string), |
| 41 | and executes it with exec-direction set to 'reverse'. |
| 42 | |
| 43 | Used to implement reverse-next etc. commands. */ |
| 44 | |
| 45 | static void |
| 46 | exec_reverse_once (char *cmd, char *args, int from_tty) |
| 47 | { |
| 48 | char *reverse_command; |
| 49 | enum exec_direction_kind dir = execution_direction; |
| 50 | struct cleanup *old_chain; |
| 51 | |
| 52 | if (dir == EXEC_REVERSE) |
| 53 | error (_("Already in reverse mode. Use '%s' or 'set exec-dir forward'."), |
| 54 | cmd); |
| 55 | |
| 56 | if (!target_can_execute_reverse) |
| 57 | error (_("Target %s does not support this command."), target_shortname); |
| 58 | |
| 59 | reverse_command = xstrprintf ("%s %s", cmd, args ? args : ""); |
| 60 | old_chain = make_cleanup (exec_direction_default, NULL); |
| 61 | make_cleanup (xfree, reverse_command); |
| 62 | execution_direction = EXEC_REVERSE; |
| 63 | execute_command (reverse_command, from_tty); |
| 64 | do_cleanups (old_chain); |
| 65 | } |
| 66 | |
| 67 | static void |
| 68 | reverse_step (char *args, int from_tty) |
| 69 | { |
| 70 | exec_reverse_once ("step", args, from_tty); |
| 71 | } |
| 72 | |
| 73 | static void |
| 74 | reverse_stepi (char *args, int from_tty) |
| 75 | { |
| 76 | exec_reverse_once ("stepi", args, from_tty); |
| 77 | } |
| 78 | |
| 79 | static void |
| 80 | reverse_next (char *args, int from_tty) |
| 81 | { |
| 82 | exec_reverse_once ("next", args, from_tty); |
| 83 | } |
| 84 | |
| 85 | static void |
| 86 | reverse_nexti (char *args, int from_tty) |
| 87 | { |
| 88 | exec_reverse_once ("nexti", args, from_tty); |
| 89 | } |
| 90 | |
| 91 | static void |
| 92 | reverse_continue (char *args, int from_tty) |
| 93 | { |
| 94 | exec_reverse_once ("continue", args, from_tty); |
| 95 | } |
| 96 | |
| 97 | static void |
| 98 | reverse_finish (char *args, int from_tty) |
| 99 | { |
| 100 | exec_reverse_once ("finish", args, from_tty); |
| 101 | } |
| 102 | |
| 103 | /* Data structures for a bookmark list. */ |
| 104 | |
| 105 | struct bookmark { |
| 106 | struct bookmark *next; |
| 107 | int number; |
| 108 | CORE_ADDR pc; |
| 109 | struct symtab_and_line sal; |
| 110 | gdb_byte *opaque_data; |
| 111 | }; |
| 112 | |
| 113 | static struct bookmark *bookmark_chain; |
| 114 | static int bookmark_count; |
| 115 | |
| 116 | #define ALL_BOOKMARKS(B) for ((B) = bookmark_chain; (B); (B) = (B)->next) |
| 117 | |
| 118 | #define ALL_BOOKMARKS_SAFE(B,TMP) \ |
| 119 | for ((B) = bookmark_chain; \ |
| 120 | (B) ? ((TMP) = (B)->next, 1) : 0; \ |
| 121 | (B) = (TMP)) |
| 122 | |
| 123 | /* save_bookmark_command -- implement "bookmark" command. |
| 124 | Call target method to get a bookmark identifier. |
| 125 | Insert bookmark identifier into list. |
| 126 | |
| 127 | Identifier will be a malloc string (gdb_byte *). |
| 128 | Up to us to free it as required. */ |
| 129 | |
| 130 | static void |
| 131 | save_bookmark_command (char *args, int from_tty) |
| 132 | { |
| 133 | /* Get target's idea of a bookmark. */ |
| 134 | gdb_byte *bookmark_id = target_get_bookmark (args, from_tty); |
| 135 | struct bookmark *b, *b1; |
| 136 | struct gdbarch *gdbarch = get_regcache_arch (get_current_regcache ()); |
| 137 | |
| 138 | /* CR should not cause another identical bookmark. */ |
| 139 | dont_repeat (); |
| 140 | |
| 141 | if (bookmark_id == NULL) |
| 142 | error (_("target_get_bookmark failed.")); |
| 143 | |
| 144 | /* Set up a bookmark struct. */ |
| 145 | b = XCNEW (struct bookmark); |
| 146 | b->number = ++bookmark_count; |
| 147 | init_sal (&b->sal); |
| 148 | b->pc = regcache_read_pc (get_current_regcache ()); |
| 149 | b->sal = find_pc_line (b->pc, 0); |
| 150 | b->sal.pspace = get_frame_program_space (get_current_frame ()); |
| 151 | b->opaque_data = bookmark_id; |
| 152 | b->next = NULL; |
| 153 | |
| 154 | /* Add this bookmark to the end of the chain, so that a list |
| 155 | of bookmarks will come out in order of increasing numbers. */ |
| 156 | |
| 157 | b1 = bookmark_chain; |
| 158 | if (b1 == 0) |
| 159 | bookmark_chain = b; |
| 160 | else |
| 161 | { |
| 162 | while (b1->next) |
| 163 | b1 = b1->next; |
| 164 | b1->next = b; |
| 165 | } |
| 166 | printf_filtered (_("Saved bookmark %d at %s\n"), b->number, |
| 167 | paddress (gdbarch, b->sal.pc)); |
| 168 | } |
| 169 | |
| 170 | /* Implement "delete bookmark" command. */ |
| 171 | |
| 172 | static int |
| 173 | delete_one_bookmark (int num) |
| 174 | { |
| 175 | struct bookmark *b1, *b; |
| 176 | |
| 177 | /* Find bookmark with corresponding number. */ |
| 178 | ALL_BOOKMARKS (b) |
| 179 | if (b->number == num) |
| 180 | break; |
| 181 | |
| 182 | /* Special case, first item in list. */ |
| 183 | if (b == bookmark_chain) |
| 184 | bookmark_chain = b->next; |
| 185 | |
| 186 | /* Find bookmark preceding "marked" one, so we can unlink. */ |
| 187 | if (b) |
| 188 | { |
| 189 | ALL_BOOKMARKS (b1) |
| 190 | if (b1->next == b) |
| 191 | { |
| 192 | /* Found designated bookmark. Unlink and delete. */ |
| 193 | b1->next = b->next; |
| 194 | break; |
| 195 | } |
| 196 | xfree (b->opaque_data); |
| 197 | xfree (b); |
| 198 | return 1; /* success */ |
| 199 | } |
| 200 | return 0; /* failure */ |
| 201 | } |
| 202 | |
| 203 | static void |
| 204 | delete_all_bookmarks (void) |
| 205 | { |
| 206 | struct bookmark *b, *b1; |
| 207 | |
| 208 | ALL_BOOKMARKS_SAFE (b, b1) |
| 209 | { |
| 210 | xfree (b->opaque_data); |
| 211 | xfree (b); |
| 212 | } |
| 213 | bookmark_chain = NULL; |
| 214 | } |
| 215 | |
| 216 | static void |
| 217 | delete_bookmark_command (char *args, int from_tty) |
| 218 | { |
| 219 | int num; |
| 220 | struct get_number_or_range_state state; |
| 221 | |
| 222 | if (bookmark_chain == NULL) |
| 223 | { |
| 224 | warning (_("No bookmarks.")); |
| 225 | return; |
| 226 | } |
| 227 | |
| 228 | if (args == NULL || args[0] == '\0') |
| 229 | { |
| 230 | if (from_tty && !query (_("Delete all bookmarks? "))) |
| 231 | return; |
| 232 | delete_all_bookmarks (); |
| 233 | return; |
| 234 | } |
| 235 | |
| 236 | init_number_or_range (&state, args); |
| 237 | while (!state.finished) |
| 238 | { |
| 239 | num = get_number_or_range (&state); |
| 240 | if (!delete_one_bookmark (num)) |
| 241 | /* Not found. */ |
| 242 | warning (_("No bookmark #%d."), num); |
| 243 | } |
| 244 | } |
| 245 | |
| 246 | /* Implement "goto-bookmark" command. */ |
| 247 | |
| 248 | static void |
| 249 | goto_bookmark_command (char *args, int from_tty) |
| 250 | { |
| 251 | struct bookmark *b; |
| 252 | unsigned long num; |
| 253 | char *p = args; |
| 254 | |
| 255 | if (args == NULL || args[0] == '\0') |
| 256 | error (_("Command requires an argument.")); |
| 257 | |
| 258 | if (startswith (args, "start") |
| 259 | || startswith (args, "begin") |
| 260 | || startswith (args, "end")) |
| 261 | { |
| 262 | /* Special case. Give target opportunity to handle. */ |
| 263 | target_goto_bookmark ((gdb_byte *) args, from_tty); |
| 264 | return; |
| 265 | } |
| 266 | |
| 267 | if (args[0] == '\'' || args[0] == '\"') |
| 268 | { |
| 269 | /* Special case -- quoted string. Pass on to target. */ |
| 270 | if (args[strlen (args) - 1] != args[0]) |
| 271 | error (_("Unbalanced quotes: %s"), args); |
| 272 | target_goto_bookmark ((gdb_byte *) args, from_tty); |
| 273 | return; |
| 274 | } |
| 275 | |
| 276 | /* General case. Bookmark identified by bookmark number. */ |
| 277 | num = get_number (&args); |
| 278 | |
| 279 | if (num == 0) |
| 280 | error (_("goto-bookmark: invalid bookmark number '%s'."), p); |
| 281 | |
| 282 | ALL_BOOKMARKS (b) |
| 283 | if (b->number == num) |
| 284 | break; |
| 285 | |
| 286 | if (b) |
| 287 | { |
| 288 | /* Found. Send to target method. */ |
| 289 | target_goto_bookmark (b->opaque_data, from_tty); |
| 290 | return; |
| 291 | } |
| 292 | /* Not found. */ |
| 293 | error (_("goto-bookmark: no bookmark found for '%s'."), p); |
| 294 | } |
| 295 | |
| 296 | static int |
| 297 | bookmark_1 (int bnum) |
| 298 | { |
| 299 | struct gdbarch *gdbarch = get_regcache_arch (get_current_regcache ()); |
| 300 | struct bookmark *b; |
| 301 | int matched = 0; |
| 302 | |
| 303 | ALL_BOOKMARKS (b) |
| 304 | { |
| 305 | if (bnum == -1 || bnum == b->number) |
| 306 | { |
| 307 | printf_filtered (" %d %s '%s'\n", |
| 308 | b->number, |
| 309 | paddress (gdbarch, b->pc), |
| 310 | b->opaque_data); |
| 311 | matched++; |
| 312 | } |
| 313 | } |
| 314 | |
| 315 | if (bnum > 0 && matched == 0) |
| 316 | printf_filtered ("No bookmark #%d\n", bnum); |
| 317 | |
| 318 | return matched; |
| 319 | } |
| 320 | |
| 321 | /* Implement "info bookmarks" command. */ |
| 322 | |
| 323 | static void |
| 324 | bookmarks_info (char *args, int from_tty) |
| 325 | { |
| 326 | int bnum = -1; |
| 327 | |
| 328 | if (!bookmark_chain) |
| 329 | printf_filtered (_("No bookmarks.\n")); |
| 330 | else if (args == NULL || *args == '\0') |
| 331 | bookmark_1 (-1); |
| 332 | else |
| 333 | { |
| 334 | struct get_number_or_range_state state; |
| 335 | |
| 336 | init_number_or_range (&state, args); |
| 337 | while (!state.finished) |
| 338 | { |
| 339 | bnum = get_number_or_range (&state); |
| 340 | bookmark_1 (bnum); |
| 341 | } |
| 342 | } |
| 343 | } |
| 344 | |
| 345 | |
| 346 | /* Provide a prototype to silence -Wmissing-prototypes. */ |
| 347 | extern initialize_file_ftype _initialize_reverse; |
| 348 | |
| 349 | void |
| 350 | _initialize_reverse (void) |
| 351 | { |
| 352 | add_com ("reverse-step", class_run, reverse_step, _("\ |
| 353 | Step program backward until it reaches the beginning of another source line.\n\ |
| 354 | Argument N means do this N times (or till program stops for another reason).") |
| 355 | ); |
| 356 | add_com_alias ("rs", "reverse-step", class_alias, 1); |
| 357 | |
| 358 | add_com ("reverse-next", class_run, reverse_next, _("\ |
| 359 | Step program backward, proceeding through subroutine calls.\n\ |
| 360 | Like the \"reverse-step\" command as long as subroutine calls do not happen;\n\ |
| 361 | when they do, the call is treated as one instruction.\n\ |
| 362 | Argument N means do this N times (or till program stops for another reason).") |
| 363 | ); |
| 364 | add_com_alias ("rn", "reverse-next", class_alias, 1); |
| 365 | |
| 366 | add_com ("reverse-stepi", class_run, reverse_stepi, _("\ |
| 367 | Step backward exactly one instruction.\n\ |
| 368 | Argument N means do this N times (or till program stops for another reason).") |
| 369 | ); |
| 370 | add_com_alias ("rsi", "reverse-stepi", class_alias, 0); |
| 371 | |
| 372 | add_com ("reverse-nexti", class_run, reverse_nexti, _("\ |
| 373 | Step backward one instruction, but proceed through called subroutines.\n\ |
| 374 | Argument N means do this N times (or till program stops for another reason).") |
| 375 | ); |
| 376 | add_com_alias ("rni", "reverse-nexti", class_alias, 0); |
| 377 | |
| 378 | add_com ("reverse-continue", class_run, reverse_continue, _("\ |
| 379 | Continue program being debugged but run it in reverse.\n\ |
| 380 | If proceeding from breakpoint, a number N may be used as an argument,\n\ |
| 381 | which means to set the ignore count of that breakpoint to N - 1 (so that\n\ |
| 382 | the breakpoint won't break until the Nth time it is reached).")); |
| 383 | add_com_alias ("rc", "reverse-continue", class_alias, 0); |
| 384 | |
| 385 | add_com ("reverse-finish", class_run, reverse_finish, _("\ |
| 386 | Execute backward until just before selected stack frame is called.")); |
| 387 | |
| 388 | add_com ("bookmark", class_bookmark, save_bookmark_command, _("\ |
| 389 | Set a bookmark in the program's execution history.\n\ |
| 390 | A bookmark represents a point in the execution history \n\ |
| 391 | that can be returned to at a later point in the debug session.")); |
| 392 | add_info ("bookmarks", bookmarks_info, _("\ |
| 393 | Status of user-settable bookmarks.\n\ |
| 394 | Bookmarks are user-settable markers representing a point in the \n\ |
| 395 | execution history that can be returned to later in the same debug \n\ |
| 396 | session.")); |
| 397 | add_cmd ("bookmark", class_bookmark, delete_bookmark_command, _("\ |
| 398 | Delete a bookmark from the bookmark list.\n\ |
| 399 | Argument is a bookmark number or numbers,\n\ |
| 400 | or no argument to delete all bookmarks.\n"), |
| 401 | &deletelist); |
| 402 | add_com ("goto-bookmark", class_bookmark, goto_bookmark_command, _("\ |
| 403 | Go to an earlier-bookmarked point in the program's execution history.\n\ |
| 404 | Argument is the bookmark number of a bookmark saved earlier by using \n\ |
| 405 | the 'bookmark' command, or the special arguments:\n\ |
| 406 | start (beginning of recording)\n\ |
| 407 | end (end of recording)\n")); |
| 408 | } |