1 /* Reverse execution and reverse debugging. 2 3 Copyright (C) 2006, 2007, 2008, 2009 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 28 /* User interface: 29 reverse-step, reverse-next etc. */ 30 31 static void 32 exec_direction_default (void *notused) 33 { 34 /* Return execution direction to default state. */ 35 execution_direction = EXEC_FORWARD; 36 } 37 38 /* exec_reverse_once -- accepts an arbitrary gdb command (string), 39 and executes it with exec-direction set to 'reverse'. 40 41 Used to implement reverse-next etc. commands. */ 42 43 static void 44 exec_reverse_once (char *cmd, char *args, int from_tty) 45 { 46 char *reverse_command; 47 enum exec_direction_kind dir = execution_direction; 48 struct cleanup *old_chain; 49 50 if (dir == EXEC_ERROR) 51 error (_("Target %s does not support this command."), target_shortname); 52 53 if (dir == EXEC_REVERSE) 54 error (_("Already in reverse mode. Use '%s' or 'set exec-dir forward'."), 55 cmd); 56 57 if (!target_can_execute_reverse) 58 error (_("Target %s does not support this command."), target_shortname); 59 60 reverse_command = xstrprintf ("%s %s", cmd, args ? args : ""); 61 old_chain = make_cleanup (exec_direction_default, NULL); 62 make_cleanup (xfree, reverse_command); 63 execution_direction = EXEC_REVERSE; 64 execute_command (reverse_command, from_tty); 65 do_cleanups (old_chain); 66 } 67 68 static void 69 reverse_step (char *args, int from_tty) 70 { 71 exec_reverse_once ("step", args, from_tty); 72 } 73 74 static void 75 reverse_stepi (char *args, int from_tty) 76 { 77 exec_reverse_once ("stepi", args, from_tty); 78 } 79 80 static void 81 reverse_next (char *args, int from_tty) 82 { 83 exec_reverse_once ("next", args, from_tty); 84 } 85 86 static void 87 reverse_nexti (char *args, int from_tty) 88 { 89 exec_reverse_once ("nexti", args, from_tty); 90 } 91 92 static void 93 reverse_continue (char *args, int from_tty) 94 { 95 exec_reverse_once ("continue", args, from_tty); 96 } 97 98 static void 99 reverse_finish (char *args, int from_tty) 100 { 101 exec_reverse_once ("finish", args, from_tty); 102 } 103 104 /* Provide a prototype to silence -Wmissing-prototypes. */ 105 extern initialize_file_ftype _initialize_reverse; 106 107 void 108 _initialize_reverse (void) 109 { 110 add_com ("reverse-step", class_run, reverse_step, _("\ 111 Step program backward until it reaches the beginning of another source line.\n\ 112 Argument N means do this N times (or till program stops for another reason).") 113 ); 114 add_com_alias ("rs", "reverse-step", class_alias, 1); 115 116 add_com ("reverse-next", class_run, reverse_next, _("\ 117 Step program backward, proceeding through subroutine calls.\n\ 118 Like the \"reverse-step\" command as long as subroutine calls do not happen;\n\ 119 when they do, the call is treated as one instruction.\n\ 120 Argument N means do this N times (or till program stops for another reason).") 121 ); 122 add_com_alias ("rn", "reverse-next", class_alias, 1); 123 124 add_com ("reverse-stepi", class_run, reverse_stepi, _("\ 125 Step backward exactly one instruction.\n\ 126 Argument N means do this N times (or till program stops for another reason).") 127 ); 128 add_com_alias ("rsi", "reverse-stepi", class_alias, 0); 129 130 add_com ("reverse-nexti", class_run, reverse_nexti, _("\ 131 Step backward one instruction, but proceed through called subroutines.\n\ 132 Argument N means do this N times (or till program stops for another reason).") 133 ); 134 add_com_alias ("rni", "reverse-nexti", class_alias, 0); 135 136 add_com ("reverse-continue", class_run, reverse_continue, _("\ 137 Continue program being debugged but run it in reverse.\n\ 138 If proceeding from breakpoint, a number N may be used as an argument,\n\ 139 which means to set the ignore count of that breakpoint to N - 1 (so that\n\ 140 the breakpoint won't break until the Nth time it is reached).")); 141 add_com_alias ("rc", "reverse-continue", class_alias, 0); 142 143 add_com ("reverse-finish", class_run, reverse_finish, _("\ 144 Execute backward until just before selected stack frame is called.")); 145 } 146