/*      $OpenBSD: db_break.c,v 1.24 2024/11/05 10:19:11 miod Exp $      */
/*      $NetBSD: db_break.c,v 1.7 1996/03/30 22:30:03 christos Exp $    */

/*
 * Mach Operating System
 * Copyright (c) 1993,1992,1991,1990 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 "AS IS"
 * 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 Mellon
 * the rights to redistribute these changes.
 *
 *      Author: David B. Golub, Carnegie Mellon University
 *      Date:   7/90
 */

/*
 * Breakpoints.
 */
#include <sys/param.h>
#include <sys/systm.h>

#include <machine/db_machdep.h>         /* type definitions */

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

#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(void);
void db_breakpoint_free(db_breakpoint_t);
void db_set_breakpoint(vaddr_t, int);
void db_delete_breakpoint(vaddr_t);
void db_list_breakpoints(void);

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

void
db_set_breakpoint(vaddr_t addr, int count)
{
        db_breakpoint_t bkpt;

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

#ifdef DB_VALID_BREAKPOINT
        if (!DB_VALID_BREAKPOINT(addr)) {
                db_printf("Not a valid address for a breakpoint.\n");
                return;
        }
#endif

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

        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(vaddr_t addr)
{
        db_breakpoint_t bkpt;
        db_breakpoint_t *prev;

        for (prev = &db_breakpoint_list; (bkpt = *prev) != 0;
            prev = &bkpt->link) {
                if (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(vaddr_t addr)
{
        db_breakpoint_t bkpt;

        for (bkpt = db_breakpoint_list; bkpt != 0; bkpt = bkpt->link)
                if (bkpt->address == addr)
                        return (bkpt);

        return (0);
}

int db_breakpoints_inserted = 1;

void
db_set_breakpoints(void)
{
        db_breakpoint_t bkpt;

        if (!db_breakpoints_inserted) {
                for (bkpt = db_breakpoint_list; bkpt != 0; bkpt = bkpt->link) {
                        bkpt->bkpt_inst =
                            db_get_value(bkpt->address, BKPT_SIZE, 0);
                        db_put_value(bkpt->address, BKPT_SIZE,
                            BKPT_SET(bkpt->bkpt_inst));
                }
                db_breakpoints_inserted = 1;
        }
}

void
db_clear_breakpoints(void)
{
        db_breakpoint_t bkpt;

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

/*
 * 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(vaddr_t addr)
{
        db_breakpoint_t bkpt;

#ifdef DB_VALID_BREAKPOINT
        if (!DB_VALID_BREAKPOINT(addr)) {
                db_printf("Not a valid address for a breakpoint.\n");
                return (0);
        }
#endif

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

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

        bkpt->bkpt_inst = db_get_value(bkpt->address, BKPT_SIZE, 0);
        db_put_value(bkpt->address, BKPT_SIZE, BKPT_SET(bkpt->bkpt_inst));
        return bkpt;
}

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

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

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

        db_printf(" Count    Address\n");
        for (bkpt = db_breakpoint_list; bkpt != 0; bkpt = bkpt->link) {
                db_printf(" %5d    ", bkpt->init_count);
                db_printsym(bkpt->address, DB_STGY_PROC, db_printf);
                db_printf("\n");
        }
}

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

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

        db_set_breakpoint((vaddr_t)addr, count);
}

/* list breakpoints */
void
db_listbreak_cmd(db_expr_t addr, int have_addr, db_expr_t count, char *modif)
{
        db_list_breakpoints();
}