osfmk/ddb/db_trap.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,
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  23  * Please see the License for the specific language governing rights and
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  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * @OSF_COPYRIGHT@
  30  */
  31 /*
  32  * Mach Operating System
  33  * Copyright (c) 1991,1990 Carnegie Mellon University
  34  * All Rights Reserved.
  35  *
  36  * Permission to use, copy, modify and distribute this software and its
  37  * documentation is hereby granted, provided that both the copyright
  38  * notice and this permission notice appear in all copies of the
  39  * software, derivative works or modified versions, and any portions
  40  * thereof, and that both notices appear in supporting documentation.
  41  *
  42  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  43  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  44  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  45  *
  46  * Carnegie Mellon requests users of this software to return to
  47  *
  48  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  49  *  School of Computer Science
  50  *  Carnegie Mellon University
  51  *  Pittsburgh PA 15213-3890
  52  *
  53  * any improvements or extensions that they make and grant Carnegie Mellon
  54  * the rights to redistribute these changes.
  55  */
  56 /*
  57  */
  58 /*
  59  *      Author: David B. Golub, Carnegie Mellon University
  60  *      Date:   7/90
  61  */
  62
  63 /*
  64  * Trap entry point to kernel debugger.
  65  */
  66 #include <mach/boolean.h>
  67 #include <machine/db_machdep.h>
  68 #include <kern/misc_protos.h>
  69 #include <ddb/db_access.h>
  70 #include <ddb/db_break.h>
  71 #include <ddb/db_command.h>
  72 #include <ddb/db_examine.h>
  73 #include <ddb/db_output.h>             /* For db_printf() */
  74 #include <ddb/db_run.h>
  75 #include <ddb/db_task_thread.h>
  76 #include <ddb/db_trap.h>
  77 #include <machine/setjmp.h>
  78
  79 extern jmp_buf_t *db_recover;
  80
  81 extern int              db_inst_count;
  82 extern int              db_load_count;
  83 extern int              db_store_count;
  84
  85 static task_t task_space;
  86 static task_t task;
  87 void
  88 db_task_trap(__unused int type, __unused int code, boolean_t user_space)
  89 {
  90         jmp_buf_t db_jmpbuf;
  91         jmp_buf_t *prev;
  92         boolean_t       bkpt;
  93         boolean_t       watchpt;
  94
  95         task = db_current_task();
  96         task_space = db_target_space(current_thread(), user_space);
  97         bkpt = IS_BREAKPOINT_TRAP(type, code);
  98         watchpt = IS_WATCHPOINT_TRAP(type, code);
  99
 100         /*
 101          * Note:  we look up PC values in an address space (task_space),
 102          * but print symbols using a (task-specific) symbol table, found
 103          * using task.
 104          */
 105
 106         /* Elided since walking the thread/task lists before setting up
 107          * safe recovery points is incorrect, and could
 108          * potentially cause us to loop and fault indefinitely.
 109          */
 110 #if 0
 111         db_init_default_act();
 112 #endif
 113         db_check_breakpoint_valid();
 114
 115         if (db_stop_at_pc(&bkpt, task, task_space)) {
 116             if (db_inst_count) {
 117                 db_printf("After %d instructions (%d loads, %d stores),\n",
 118                           db_inst_count, db_load_count, db_store_count);
 119             }
 120             if (bkpt)
 121                 db_printf("Breakpoint at  ");
 122             else if (watchpt)
 123                 db_printf("Watchpoint at  ");
 124             else
 125                 db_printf("Stopped at  ");
 126             db_dot = PC_REGS(DDB_REGS);
 127
 128             prev = db_recover;
 129             if (_setjmp(db_recover = &db_jmpbuf) == 0) {
 130 #if defined(__alpha)
 131                 db_print_loc(db_dot, task_space);
 132                 db_printf("\n\t");
 133                 db_print_inst(db_dot, task_space);
 134 #else /* !defined(__alpha) */
 135                 db_print_loc_and_inst(db_dot, task);
 136 #endif /* defined(__alpha) */
 137             } else
 138                 db_printf("Trouble printing location %#llX.\n", (unsigned long long)db_dot);
 139             db_recover = prev;
 140
 141             db_command_loop();
 142         }
 143
 144         db_restart_at_pc(watchpt, task_space);
 145 }