sys/ddb/db_break.c

/*
 * Mach Operating System
 * Copyright (c) 1991,1990 Carnegie Mellon University
 * All Rights Reserved.
 *
 * Permission to use, copy, modify and distribute this software and its
 * documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 *
 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS
 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 *
 * Carnegie Mellon requests users of this software to return to
 *
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 *
 * any improvements or extensions that they make and grant Carnegie the
 * rights to redistribute these changes.
 *
 *      $Id: db_break.c,v 1.2 1993/10/16 16:47:07 rgrimes Exp $
 */

/*
 *      Author: David B. Golub, Carnegie Mellon University
 *      Date:   7/90
 */
/*
 * Breakpoints.
 */
#include "param.h"
#include "systm.h"
#include "proc.h"
#include "ddb/ddb.h"

#include <ddb/db_lex.h>
#include <ddb/db_break.h>
#include <ddb/db_access.h>
#include <ddb/db_sym.h>
#include <ddb/db_break.h>

extern boolean_t db_map_equal();
extern boolean_t db_map_current();
extern vm_map_t db_map_addr();

#define NBREAKPOINTS    100
struct db_breakpoint    db_break_table[NBREAKPOINTS];
db_breakpoint_t         db_next_free_breakpoint = &db_break_table[0];
db_breakpoint_t         db_free_breakpoints = 0;
db_breakpoint_t         db_breakpoint_list = 0;

db_breakpoint_t
db_breakpoint_alloc()
{
        register db_breakpoint_t        bkpt;

        if ((bkpt = db_free_breakpoints) != 0) {
            db_free_breakpoints = bkpt->link;
            return (bkpt);
        }
        if (db_next_free_breakpoint == &db_break_table[NBREAKPOINTS]) {
            db_printf("All breakpoints used.\n");
            return (0);
        }
        bkpt = db_next_free_breakpoint;
        db_next_free_breakpoint++;

        return (bkpt);
}

void
db_breakpoint_free(bkpt)
        register db_breakpoint_t        bkpt;
{
        bkpt->link = db_free_breakpoints;
        db_free_breakpoints = bkpt;
}

void
db_set_breakpoint(map, addr, count)
        vm_map_t        map;
        db_addr_t       addr;
        int             count;
{
        register db_breakpoint_t        bkpt;

        if (db_find_breakpoint(map, addr)) {
            db_printf("Already set.\n");
            return;
        }

        bkpt = db_breakpoint_alloc();
        if (bkpt == 0) {
            db_printf("Too many breakpoints.\n");
            return;
        }

        bkpt->map = map;
        bkpt->address = addr;
        bkpt->flags = 0;
        bkpt->init_count = count;
        bkpt->count = count;

        bkpt->link = db_breakpoint_list;
        db_breakpoint_list = bkpt;
}

void
db_delete_breakpoint(map, addr)
        vm_map_t        map;
        db_addr_t       addr;
{
        register db_breakpoint_t        bkpt;
        register db_breakpoint_t        *prev;

        for (prev = &db_breakpoint_list;
             (bkpt = *prev) != 0;
             prev = &bkpt->link) {
            if (db_map_equal(bkpt->map, map) &&
                (bkpt->address == addr)) {
                *prev = bkpt->link;
                break;
            }
        }
        if (bkpt == 0) {
            db_printf("Not set.\n");
            return;
        }

        db_breakpoint_free(bkpt);
}

db_breakpoint_t
db_find_breakpoint(map, addr)
        vm_map_t        map;
        db_addr_t       addr;
{
        register db_breakpoint_t        bkpt;

        for (bkpt = db_breakpoint_list;
             bkpt != 0;
             bkpt = bkpt->link)
        {
            if (db_map_equal(bkpt->map, map) &&
                (bkpt->address == addr))
                return (bkpt);
        }
        return (0);
}

db_breakpoint_t
db_find_breakpoint_here(addr)
        db_addr_t       addr;
{
    return db_find_breakpoint(db_map_addr(addr), addr);
}

boolean_t       db_breakpoints_inserted = TRUE;

void
db_set_breakpoints()
{
        register db_breakpoint_t        bkpt;

        if (!db_breakpoints_inserted) {

            for (bkpt = db_breakpoint_list;
                 bkpt != 0;
                 bkpt = bkpt->link)
                if (db_map_current(bkpt->map)) {
                    bkpt->bkpt_inst = db_get_value(bkpt->address,
                                                   BKPT_SIZE,
                                                   FALSE);
                    db_put_value(bkpt->address,
                                 BKPT_SIZE,
                                 BKPT_SET(bkpt->bkpt_inst));
                }
            db_breakpoints_inserted = TRUE;
        }
}

void
db_clear_breakpoints()
{
        register db_breakpoint_t        bkpt;

        if (db_breakpoints_inserted) {

            for (bkpt = db_breakpoint_list;
                 bkpt != 0;
                 bkpt = bkpt->link)
                if (db_map_current(bkpt->map)) {
                    db_put_value(bkpt->address, BKPT_SIZE, bkpt->bkpt_inst);
                }
            db_breakpoints_inserted = FALSE;
        }
}

/*
 * Set a temporary breakpoint.
 * The instruction is changed immediately,
 * so the breakpoint does not have to be on the breakpoint list.
 */
db_breakpoint_t
db_set_temp_breakpoint(addr)
        db_addr_t       addr;
{
        register db_breakpoint_t        bkpt;

        bkpt = db_breakpoint_alloc();
        if (bkpt == 0) {
            db_printf("Too many breakpoints.\n");
            return 0;
        }

        bkpt->map = NULL;
        bkpt->address = addr;
        bkpt->flags = BKPT_TEMP;
        bkpt->init_count = 1;
        bkpt->count = 1;

        bkpt->bkpt_inst = db_get_value(bkpt->address, BKPT_SIZE, FALSE);
        db_put_value(bkpt->address, BKPT_SIZE, BKPT_SET(bkpt->bkpt_inst));
        return bkpt;
}

void
db_delete_temp_breakpoint(bkpt)
        db_breakpoint_t bkpt;
{
        db_put_value(bkpt->address, BKPT_SIZE, bkpt->bkpt_inst);
        db_breakpoint_free(bkpt);
}

/*
 * List breakpoints.
 */
void
db_list_breakpoints()
{
        register db_breakpoint_t        bkpt;

        if (db_breakpoint_list == 0) {
            db_printf("No breakpoints set\n");
            return;
        }

        db_printf(" Map      Count    Address\n");
        for (bkpt = db_breakpoint_list;
             bkpt != 0;
             bkpt = bkpt->link)
        {
            db_printf("%s%8x %5d    ",
                      db_map_current(bkpt->map) ? "*" : " ",
                      bkpt->map, bkpt->init_count);
            db_printsym(bkpt->address, DB_STGY_PROC);
            db_printf("\n");
        }
}

/* Delete breakpoint */
/*ARGSUSED*/
void
db_delete_cmd(addr, have_addr, count, modif)
        db_expr_t       addr;
        int             have_addr;
        db_expr_t       count;
        char *          modif;
{
        db_delete_breakpoint(db_map_addr(addr), (db_addr_t)addr);
}

/* Set breakpoint with skip count */
/*ARGSUSED*/
void
db_breakpoint_cmd(addr, have_addr, count, modif)
        db_expr_t       addr;
        int             have_addr;
        db_expr_t       count;
        char *          modif;
{
        if (count == -1)
            count = 1;

        db_set_breakpoint(db_map_addr(addr), (db_addr_t)addr, count);
}

/* list breakpoints */
void
db_listbreak_cmd(db_expr_t dummy1, int dummy2, db_expr_t dummy3, char *dummy4)
{
        db_list_breakpoints();
}

#include <vm/vm_kern.h>

/*
 *      We want ddb to be usable before most of the kernel has been
 *      initialized.  In particular, current_thread() or kernel_map
 *      (or both) may be null.
 */

boolean_t
db_map_equal(map1, map2)
        vm_map_t        map1, map2;
{
        return ((map1 == map2) ||
                ((map1 == NULL) && (map2 == kernel_map)) ||
                ((map1 == kernel_map) && (map2 == NULL)));
}

boolean_t
db_map_current(map)
        vm_map_t        map;
{
#if 0
        thread_t        thread;

        return ((map == NULL) ||
                (map == kernel_map) ||
                (((thread = current_thread()) != NULL) &&
                 (map == thread->task->map)));
#else
        return (1);
#endif
}

vm_map_t
db_map_addr(addr)
        vm_offset_t addr;
{
#if 0
        thread_t        thread;

        /*
         *      We want to return kernel_map for all
         *      non-user addresses, even when debugging
         *      kernel tasks with their own maps.
         */

        if ((VM_MIN_ADDRESS <= addr) &&
            (addr < VM_MAX_ADDRESS) &&
            ((thread = current_thread()) != NULL))
            return thread->task->map;
        else
#endif
            return kernel_map;
}