osfmk/ddb/db_trap.c

   1 /*
   2  * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
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  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * @OSF_COPYRIGHT@
  24  */
  25 /*
  26  * Mach Operating System
  27  * Copyright (c) 1991,1990 Carnegie Mellon University
  28  * All Rights Reserved.
  29  *
  30  * Permission to use, copy, modify and distribute this software and its
  31  * documentation is hereby granted, provided that both the copyright
  32  * notice and this permission notice appear in all copies of the
  33  * software, derivative works or modified versions, and any portions
  34  * thereof, and that both notices appear in supporting documentation.
  35  *
  36  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  37  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  38  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  39  *
  40  * Carnegie Mellon requests users of this software to return to
  41  *
  42  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  43  *  School of Computer Science
  44  *  Carnegie Mellon University
  45  *  Pittsburgh PA 15213-3890
  46  *
  47  * any improvements or extensions that they make and grant Carnegie Mellon
  48  * the rights to redistribute these changes.
  49  */
  50 /*
  51  */
  52 /*
  53  *      Author: David B. Golub, Carnegie Mellon University
  54  *      Date:   7/90
  55  */
  56
  57 /*
  58  * Trap entry point to kernel debugger.
  59  */
  60 #include <mach/boolean.h>
  61 #include <machine/db_machdep.h>
  62 #include <kern/misc_protos.h>
  63 #include <ddb/db_access.h>
  64 #include <ddb/db_break.h>
  65 #include <ddb/db_command.h>
  66 #include <ddb/db_examine.h>
  67 #include <ddb/db_output.h>             /* For db_printf() */
  68 #include <ddb/db_run.h>
  69 #include <ddb/db_task_thread.h>
  70 #include <ddb/db_trap.h>
  71 #include <machine/setjmp.h>
  72
  73 extern jmp_buf_t *db_recover;
  74
  75 extern int              db_inst_count;
  76 extern int              db_load_count;
  77 extern int              db_store_count;
  78
  79 void
  80 db_task_trap(
  81         int             type,
  82         int             code,
  83         boolean_t       user_space)
  84 {
  85         jmp_buf_t db_jmpbuf;
  86         jmp_buf_t *prev;
  87         boolean_t       bkpt;
  88         boolean_t       watchpt;
  89         task_t          task;
  90         task_t          task_space;
  91
  92         task = db_current_task();
  93         task_space = db_target_space(current_thread(), user_space);
  94         bkpt = IS_BREAKPOINT_TRAP(type, code);
  95         watchpt = IS_WATCHPOINT_TRAP(type, code);
  96
  97         /*
  98          * Note:  we look up PC values in an address space (task_space),
  99          * but print symbols using a (task-specific) symbol table, found
 100          * using task.
 101          */
 102
 103         /* Elided since walking the thread/task lists before setting up
 104          * safe recovery points is incorrect, and could
 105          * potentially cause us to loop and fault indefinitely.
 106          */
 107 #if 0
 108         db_init_default_act();
 109 #endif
 110         db_check_breakpoint_valid();
 111
 112         if (db_stop_at_pc(&bkpt, task, task_space)) {
 113             if (db_inst_count) {
 114                 db_printf("After %d instructions (%d loads, %d stores),\n",
 115                           db_inst_count, db_load_count, db_store_count);
 116             }
 117             if (bkpt)
 118                 db_printf("Breakpoint at  ");
 119             else if (watchpt)
 120                 db_printf("Watchpoint at  ");
 121             else
 122                 db_printf("Stopped at  ");
 123             db_dot = PC_REGS(DDB_REGS);
 124
 125             prev = db_recover;
 126             if (_setjmp(db_recover = &db_jmpbuf) == 0) {
 127 #if defined(__alpha)
 128                 db_print_loc(db_dot, task_space);
 129                 db_printf("\n\t");
 130                 db_print_inst(db_dot, task_space);
 131 #else /* !defined(__alpha) */
 132 #if defined(__ppc__)
 133                 db_print_loc_and_inst(db_dot, task_space);
 134 #else   /* __ppc__ */
 135                 db_print_loc_and_inst(db_dot, task);
 136 #endif  /* __ppc__ */
 137 #endif /* defined(__alpha) */
 138             } else
 139                 db_printf("Trouble printing location %#llX.\n", (unsigned long long)db_dot);
 140             db_recover = prev;
 141
 142             db_command_loop();
 143         }
 144
 145         db_restart_at_pc(watchpt, task_space);
 146 }