1 /* Reverse execution and reverse debugging. 2 3 Copyright (C) 2006, 2007, 2008, 2009, 2010 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 "gdb_string.h" 22 #include "target.h" 23 #include "top.h" 24 #include "cli/cli-cmds.h" 25 #include "cli/cli-decode.h" 26 #include "inferior.h" 27 #include "regcache.h" 28 29 /* User interface: 30 reverse-step, reverse-next etc. */ 31 32 static void 33 exec_direction_default (void *notused) 34 { 35 /* Return execution direction to default state. */ 36 execution_direction = EXEC_FORWARD; 37 } 38 39 /* exec_reverse_once -- accepts an arbitrary gdb command (string), 40 and executes it with exec-direction set to 'reverse'. 41 42 Used to implement reverse-next etc. commands. */ 43 44 static void 45 exec_reverse_once (char *cmd, char *args, int from_tty) 46 { 47 char *reverse_command; 48 enum exec_direction_kind dir = execution_direction; 49 struct cleanup *old_chain; 50 51 if (dir == EXEC_ERROR) 52 error (_("Target %s does not support this command."), target_shortname); 53 54 if (dir == EXEC_REVERSE) 55 error (_("Already in reverse mode. Use '%s' or 'set exec-dir forward'."), 56 cmd); 57 58 if (!target_can_execute_reverse) 59 error (_("Target %s does not support this command."), target_shortname); 60 61 reverse_command = xstrprintf ("%s %s", cmd, args ? args : ""); 62 old_chain = make_cleanup (exec_direction_default, NULL); 63 make_cleanup (xfree, reverse_command); 64 execution_direction = EXEC_REVERSE; 65 execute_command (reverse_command, from_tty); 66 do_cleanups (old_chain); 67 } 68 69 static void 70 reverse_step (char *args, int from_tty) 71 { 72 exec_reverse_once ("step", args, from_tty); 73 } 74 75 static void 76 reverse_stepi (char *args, int from_tty) 77 { 78 exec_reverse_once ("stepi", args, from_tty); 79 } 80 81 static void 82 reverse_next (char *args, int from_tty) 83 { 84 exec_reverse_once ("next", args, from_tty); 85 } 86 87 static void 88 reverse_nexti (char *args, int from_tty) 89 { 90 exec_reverse_once ("nexti", args, from_tty); 91 } 92 93 static void 94 reverse_continue (char *args, int from_tty) 95 { 96 exec_reverse_once ("continue", args, from_tty); 97 } 98 99 static void 100 reverse_finish (char *args, int from_tty) 101 { 102 exec_reverse_once ("finish", args, from_tty); 103 } 104 105 /* Data structures for a bookmark list. */ 106 107 struct bookmark { 108 struct bookmark *next; 109 int number; 110 CORE_ADDR pc; 111 struct symtab_and_line sal; 112 gdb_byte *opaque_data; 113 }; 114 115 static struct bookmark *bookmark_chain; 116 static int bookmark_count; 117 118 #define ALL_BOOKMARKS(B) for ((B) = bookmark_chain; (B); (B) = (B)->next) 119 120 #define ALL_BOOKMARKS_SAFE(B,TMP) \ 121 for ((B) = bookmark_chain; \ 122 (B) ? ((TMP) = (B)->next, 1) : 0; \ 123 (B) = (TMP)) 124 125 /* save_bookmark_command -- implement "bookmark" command. 126 Call target method to get a bookmark identifier. 127 Insert bookmark identifier into list. 128 129 Identifier will be a malloc string (gdb_byte *). 130 Up to us to free it as required. */ 131 132 static void 133 save_bookmark_command (char *args, int from_tty) 134 { 135 /* Get target's idea of a bookmark. */ 136 gdb_byte *bookmark_id = target_get_bookmark (args, from_tty); 137 struct bookmark *b, *b1; 138 struct gdbarch *gdbarch = get_regcache_arch (get_current_regcache ()); 139 140 /* CR should not cause another identical bookmark. */ 141 dont_repeat (); 142 143 if (bookmark_id == NULL) 144 error (_("target_get_bookmark failed.")); 145 146 /* Set up a bookmark struct. */ 147 b = xcalloc (1, sizeof (struct bookmark)); 148 b->number = ++bookmark_count; 149 init_sal (&b->sal); 150 b->pc = regcache_read_pc (get_current_regcache ()); 151 b->sal = find_pc_line (b->pc, 0); 152 b->sal.pspace = get_frame_program_space (get_current_frame ()); 153 b->opaque_data = bookmark_id; 154 b->next = NULL; 155 156 /* Add this bookmark to the end of the chain, so that a list 157 of bookmarks will come out in order of increasing numbers. */ 158 159 b1 = bookmark_chain; 160 if (b1 == 0) 161 bookmark_chain = b; 162 else 163 { 164 while (b1->next) 165 b1 = b1->next; 166 b1->next = b; 167 } 168 printf_filtered (_("Saved bookmark %d at %s\n"), b->number, 169 paddress (gdbarch, b->sal.pc)); 170 } 171 172 /* Implement "delete bookmark" command. */ 173 174 static int 175 delete_one_bookmark (struct bookmark *b) 176 { 177 struct bookmark *b1; 178 179 /* Special case, first item in list. */ 180 if (b == bookmark_chain) 181 bookmark_chain = b->next; 182 183 /* Find bookmark preceeding "marked" one, so we can unlink. */ 184 if (b) 185 { 186 ALL_BOOKMARKS (b1) 187 if (b1->next == b) 188 { 189 /* Found designated bookmark. Unlink and delete. */ 190 b1->next = b->next; 191 break; 192 } 193 xfree (b->opaque_data); 194 xfree (b); 195 return 1; /* success */ 196 } 197 return 0; /* failure */ 198 } 199 200 static void 201 delete_all_bookmarks (void) 202 { 203 struct bookmark *b, *b1; 204 205 ALL_BOOKMARKS_SAFE (b, b1) 206 { 207 xfree (b->opaque_data); 208 xfree (b); 209 } 210 bookmark_chain = NULL; 211 } 212 213 static void 214 delete_bookmark_command (char *args, int from_tty) 215 { 216 struct bookmark *b; 217 unsigned long num; 218 219 if (bookmark_chain == NULL) 220 { 221 warning (_("No bookmarks.")); 222 return; 223 } 224 225 if (args == NULL || args[0] == '\0') 226 { 227 if (from_tty && !query (_("Delete all bookmarks? "))) 228 return; 229 delete_all_bookmarks (); 230 return; 231 } 232 233 num = strtoul (args, NULL, 0); 234 /* Find bookmark with corresponding number. */ 235 ALL_BOOKMARKS (b) 236 if (b->number == num) 237 break; 238 239 if (!delete_one_bookmark (b)) 240 /* Not found. */ 241 error (_("delete bookmark: no bookmark found for '%s'."), args); 242 } 243 244 /* Implement "goto-bookmark" command. */ 245 246 static void 247 goto_bookmark_command (char *args, int from_tty) 248 { 249 struct bookmark *b; 250 unsigned long num; 251 252 if (args == NULL || args[0] == '\0') 253 error (_("Command requires an argument.")); 254 255 if (strncmp (args, "start", strlen ("start")) == 0 256 || strncmp (args, "begin", strlen ("begin")) == 0 257 || strncmp (args, "end", strlen ("end")) == 0) 258 { 259 /* Special case. Give target opportunity to handle. */ 260 target_goto_bookmark (args, from_tty); 261 return; 262 } 263 264 if (args[0] == '\'' || args[0] == '\"') 265 { 266 /* Special case -- quoted string. Pass on to target. */ 267 if (args[strlen (args) - 1] != args[0]) 268 error (_("Unbalanced quotes: %s"), args); 269 target_goto_bookmark (args, from_tty); 270 return; 271 } 272 273 /* General case. Bookmark identified by bookmark number. */ 274 num = strtoul (args, NULL, 0); 275 ALL_BOOKMARKS (b) 276 if (b->number == num) 277 break; 278 279 if (b) 280 { 281 /* Found. Send to target method. */ 282 target_goto_bookmark (b->opaque_data, from_tty); 283 return; 284 } 285 /* Not found. */ 286 error (_("goto-bookmark: no bookmark found for '%s'."), args); 287 } 288 289 /* Implement "info bookmarks" command. */ 290 291 static void 292 bookmarks_info (char *args, int from_tty) 293 { 294 struct bookmark *b; 295 int bnum = -1; 296 struct gdbarch *gdbarch; 297 298 if (args) 299 bnum = parse_and_eval_long (args); 300 301 if (!bookmark_chain) 302 { 303 printf_filtered (_("No bookmarks.\n")); 304 return; 305 } 306 307 gdbarch = get_regcache_arch (get_current_regcache ()); 308 printf_filtered (_("Bookmark Address Opaque\n")); 309 printf_filtered (_(" ID Data\n")); 310 311 ALL_BOOKMARKS (b) 312 printf_filtered (" %d %s '%s'\n", 313 b->number, 314 paddress (gdbarch, b->pc), 315 b->opaque_data); 316 } 317 318 319 /* Provide a prototype to silence -Wmissing-prototypes. */ 320 extern initialize_file_ftype _initialize_reverse; 321 322 void 323 _initialize_reverse (void) 324 { 325 add_com ("reverse-step", class_run, reverse_step, _("\ 326 Step program backward until it reaches the beginning of another source line.\n\ 327 Argument N means do this N times (or till program stops for another reason).") 328 ); 329 add_com_alias ("rs", "reverse-step", class_alias, 1); 330 331 add_com ("reverse-next", class_run, reverse_next, _("\ 332 Step program backward, proceeding through subroutine calls.\n\ 333 Like the \"reverse-step\" command as long as subroutine calls do not happen;\n\ 334 when they do, the call is treated as one instruction.\n\ 335 Argument N means do this N times (or till program stops for another reason).") 336 ); 337 add_com_alias ("rn", "reverse-next", class_alias, 1); 338 339 add_com ("reverse-stepi", class_run, reverse_stepi, _("\ 340 Step backward exactly one instruction.\n\ 341 Argument N means do this N times (or till program stops for another reason).") 342 ); 343 add_com_alias ("rsi", "reverse-stepi", class_alias, 0); 344 345 add_com ("reverse-nexti", class_run, reverse_nexti, _("\ 346 Step backward one instruction, but proceed through called subroutines.\n\ 347 Argument N means do this N times (or till program stops for another reason).") 348 ); 349 add_com_alias ("rni", "reverse-nexti", class_alias, 0); 350 351 add_com ("reverse-continue", class_run, reverse_continue, _("\ 352 Continue program being debugged but run it in reverse.\n\ 353 If proceeding from breakpoint, a number N may be used as an argument,\n\ 354 which means to set the ignore count of that breakpoint to N - 1 (so that\n\ 355 the breakpoint won't break until the Nth time it is reached).")); 356 add_com_alias ("rc", "reverse-continue", class_alias, 0); 357 358 add_com ("reverse-finish", class_run, reverse_finish, _("\ 359 Execute backward until just before selected stack frame is called.")); 360 361 add_com ("bookmark", class_bookmark, save_bookmark_command, _("\ 362 Set a bookmark in the program's execution history.\n\ 363 A bookmark represents a point in the execution history \n\ 364 that can be returned to at a later point in the debug session.")); 365 add_info ("bookmarks", bookmarks_info, _("\ 366 Status of user-settable bookmarks.\n\ 367 Bookmarks are user-settable markers representing a point in the \n\ 368 execution history that can be returned to later in the same debug \n\ 369 session.")); 370 add_cmd ("bookmark", class_bookmark, delete_bookmark_command, _("\ 371 Delete a bookmark from the bookmark list.\n\ 372 Argument is a bookmark number, or no argument to delete all bookmarks.\n"), 373 &deletelist); 374 add_com ("goto-bookmark", class_bookmark, goto_bookmark_command, _("\ 375 Go to an earlier-bookmarked point in the program's execution history.\n\ 376 Argument is the bookmark number of a bookmark saved earlier by using \n\ 377 the 'bookmark' command, or the special arguments:\n\ 378 start (beginning of recording)\n\ 379 end (end of recording)\n")); 380 } 381