osfmk/ddb/db_cond.c

   1 /*
   2  * Copyright (c) 2000-2005 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * @OSF_COPYRIGHT@
  30  */
  31 /*
  32  * HISTORY
  33  *
  34  * Revision 1.1.1.1  1998/09/22 21:05:47  wsanchez
  35  * Import of Mac OS X kernel (~semeria)
  36  *
  37  * Revision 1.1.1.1  1998/03/07 02:26:09  wsanchez
  38  * Import of OSF Mach kernel (~mburg)
  39  *
  40  * Revision 1.2.18.1  1997/03/27  18:46:29  barbou
  41  *      ri-osc CR1558: enable use of breakpoint counts even when no
  42  *      condition given.
  43  *      [1995/09/20  15:24:24  bolinger]
  44  *      [97/02/25            barbou]
  45  *
  46  * Revision 1.2.6.2  1996/01/09  19:15:34  devrcs
  47  *      Change 'register c' to 'register int c'.
  48  *      [1995/12/01  21:42:00  jfraser]
  49  *
  50  *      Merged '64-bit safe' changes from DEC alpha port.
  51  *      [1995/11/21  18:02:54  jfraser]
  52  *
  53  * Revision 1.2.6.1  1994/09/23  01:18:27  ezf
  54  *      change marker to not FREE
  55  *      [1994/09/22  21:09:37  ezf]
  56  *
  57  * Revision 1.2.2.4  1993/08/11  20:37:33  elliston
  58  *      Add ANSI Prototypes.  CR #9523.
  59  *      [1993/08/11  03:32:57  elliston]
  60  *
  61  * Revision 1.2.2.3  1993/07/27  18:26:59  elliston
  62  *      Add ANSI prototypes.  CR #9523.
  63  *      [1993/07/27  18:11:12  elliston]
  64  *
  65  * Revision 1.2.2.2  1993/06/09  02:19:53  gm
  66  *      Added to OSF/1 R1.3 from NMK15.0.
  67  *      [1993/06/02  20:56:04  jeffc]
  68  *
  69  * Revision 1.2  1993/04/19  16:01:51  devrcs
  70  *      Changes from mk78:
  71  *      Changed errant call of db_error in db_cond_cmd() to db_printf/db_error.
  72  *      [92/05/20            jfriedl]
  73  *      [93/02/02            bruel]
  74  *
  75  * Revision 1.1  1992/09/30  02:00:58  robert
  76  *      Initial revision
  77  *
  78  * $EndLog$
  79  */
  80 /* CMU_HIST */
  81 /*
  82  * Revision 2.2  91/10/09  15:59:09  af
  83  *       Revision 2.1.3.1  91/10/05  13:05:38  jeffreyh
  84  *              Created to support conditional break point and command execution.
  85  *              [91/08/29            tak]
  86  *
  87  * Revision 2.1.3.1  91/10/05  13:05:38  jeffreyh
  88  *      Created to support conditional break point and command execution.
  89  *      [91/08/29            tak]
  90  *
  91  */
  92 /* CMU_ENDHIST */
  93 /*
  94  * Mach Operating System
  95  * Copyright (c) 1991,1990 Carnegie Mellon University
  96  * All Rights Reserved.
  97  *
  98  * Permission to use, copy, modify and distribute this software and its
  99  * documentation is hereby granted, provided that both the copyright
 100  * notice and this permission notice appear in all copies of the
 101  * software, derivative works or modified versions, and any portions
 102  * thereof, and that both notices appear in supporting documentation.
 103  *
 104  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 105  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 106  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 107  *
 108  * Carnegie Mellon requests users of this software to return to
 109  *
 110  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 111  *  School of Computer Science
 112  *  Carnegie Mellon University
 113  *  Pittsburgh PA 15213-3890
 114  *
 115  * any improvements or extensions that they make and grant Carnegie Mellon
 116  * the rights to redistribute these changes.
 117  */
 118 /*
 119  */
 120
 121 #include <machine/db_machdep.h>
 122 #include <machine/setjmp.h>
 123 #include <kern/misc_protos.h>
 124
 125 #include <ddb/db_lex.h>
 126 #include <ddb/db_break.h>
 127 #include <ddb/db_command.h>
 128 #include <ddb/db_cond.h>
 129 #include <ddb/db_expr.h>
 130 #include <ddb/db_output.h>              /* For db_printf() */
 131
 132 #define DB_MAX_COND     10              /* maximum conditions to be set */
 133
 134 int   db_ncond_free = DB_MAX_COND;                      /* free condition */
 135 struct db_cond {
 136         int     c_size;                                 /* size of cond */
 137         char    c_cond_cmd[DB_LEX_LINE_SIZE];           /* cond & cmd */
 138 } db_cond[DB_MAX_COND];
 139
 140 void
 141 db_cond_free(db_thread_breakpoint_t bkpt)
 142 {
 143         if (bkpt->tb_cond > 0) {
 144             db_cond[bkpt->tb_cond-1].c_size = 0;
 145             db_ncond_free++;
 146             bkpt->tb_cond = 0;
 147         }
 148 }
 149
 150 extern jmp_buf_t *db_recover;
 151
 152 boolean_t
 153 db_cond_check(db_thread_breakpoint_t bkpt)
 154 {
 155         register  struct db_cond *cp;
 156         db_expr_t value;
 157         int       t;
 158         jmp_buf_t db_jmpbuf;
 159
 160         if (bkpt->tb_cond <= 0) {               /* no condition */
 161                 if (--(bkpt->tb_count) > 0)
 162                         return(FALSE);
 163                 bkpt->tb_count = bkpt->tb_init_count;
 164             return(TRUE);
 165         }
 166         db_dot = PC_REGS(DDB_REGS);
 167         db_prev = db_dot;
 168         db_next = db_dot;
 169         if (_setjmp(db_recover = &db_jmpbuf)) {
 170             /*
 171              * in case of error, return true to enter interactive mode
 172              */
 173             return(TRUE);
 174         }
 175
 176         /*
 177          * switch input, and evalutate condition
 178          */
 179         cp = &db_cond[bkpt->tb_cond - 1];
 180         db_switch_input(cp->c_cond_cmd, cp->c_size);
 181         if (!db_expression(&value)) {
 182             db_printf("error: condition evaluation error\n");
 183             return(TRUE);
 184         }
 185         if (value == 0 || --(bkpt->tb_count) > 0)
 186             return(FALSE);
 187
 188         /*
 189          * execute a command list if exist
 190          */
 191         bkpt->tb_count = bkpt->tb_init_count;
 192         if ((t = db_read_token()) != tEOL) {
 193             db_unread_token(t);
 194             return(db_exec_cmd_nest(0, 0));
 195         }
 196         return(TRUE);
 197 }
 198
 199 void
 200 db_cond_print(db_thread_breakpoint_t bkpt)
 201 {
 202         register char *p, *ep;
 203         register struct db_cond *cp;
 204
 205         if (bkpt->tb_cond <= 0)
 206             return;
 207         cp = &db_cond[bkpt->tb_cond-1];
 208         p = cp->c_cond_cmd;
 209         ep = p + cp->c_size;
 210         while (p < ep) {
 211             if (*p == '\n' || *p == 0)
 212                 break;
 213             db_putchar(*p++);
 214         }
 215 }
 216
 217 void
 218 db_cond_cmd(void)
 219 {
 220         register  int c;
 221         register  struct db_cond *cp;
 222         register  char *p;
 223         db_expr_t value;
 224         db_thread_breakpoint_t bkpt;
 225
 226         if (db_read_token() != tHASH || db_read_token() != tNUMBER) {
 227             db_printf("#<number> expected instead of \"%s\"\n", db_tok_string);
 228             db_error(0);
 229             return;
 230         }
 231         if ((bkpt = db_find_breakpoint_number((int)db_tok_number, 0)) == 0) {
 232             db_printf("No such break point #%d\n", db_tok_number);
 233             db_error(0);
 234             return;
 235         }
 236         /*
 237          * if the break point already has a condition, free it first
 238          */
 239         if (bkpt->tb_cond > 0) {
 240             cp = &db_cond[bkpt->tb_cond - 1];
 241             db_cond_free(bkpt);
 242         } else {
 243             if (db_ncond_free <= 0) {
 244                 db_error("Too many conditions\n");
 245                 return;
 246             }
 247             for (cp = db_cond; cp < &db_cond[DB_MAX_COND]; cp++)
 248                 if (cp->c_size == 0)
 249                     break;
 250             if (cp >= &db_cond[DB_MAX_COND])
 251                 panic("bad db_cond_free");
 252         }
 253         for (c = db_read_char(); c == ' ' || c == '\t'; c = db_read_char());
 254         for (p = cp->c_cond_cmd; c >= 0; c = db_read_char())
 255             *p++ = c;
 256         /*
 257          * switch to saved data and call db_expression to check the condition.
 258          * If no condition is supplied, db_expression will return false.
 259          * In this case, clear previous condition of the break point.
 260          * If condition is supplied, set the condition to the permanent area.
 261          * Note: db_expression will not return here, if the condition
 262          *       expression is wrong.
 263          */
 264         db_switch_input(cp->c_cond_cmd, p - cp->c_cond_cmd);
 265         if (!db_expression(&value)) {
 266             /* since condition is already freed, do nothing */
 267             db_flush_lex();
 268             return;
 269         }
 270         db_flush_lex();
 271         db_ncond_free--;
 272         cp->c_size = p - cp->c_cond_cmd;
 273         bkpt->tb_cond = (cp - db_cond) + 1;
 274 }