freebsd-dev/sys/ddb/db_break.c
Jake Burkholder edb333eef8 - Add a function db_alt_break which recognizes the character sequence used to
implement ALT_BREAK_TO_DEBUGGER.  The caller provides a pointer to a state
  variable to allow different state to be maintained for separate instances of
  a device.
- Use struct vm_map * instead of vm_map_t in db_break.h to avoid its users
  needing to include vm headers.

Requested by:	njl
2002-12-31 06:51:19 +00:00

410 lines
8.3 KiB
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.
*
* $FreeBSD$
*/
/*
* Author: David B. Golub, Carnegie Mellon University
* Date: 7/90
*/
/*
* Breakpoints.
*/
#include "opt_comconsole.h"
#include <sys/param.h>
#include <vm/vm.h>
#include <vm/vm_kern.h>
#include <ddb/ddb.h>
#include <ddb/db_break.h>
#include <ddb/db_access.h>
#include <ddb/db_sym.h>
#define NBREAKPOINTS 100
static struct db_breakpoint db_break_table[NBREAKPOINTS];
static db_breakpoint_t db_next_free_breakpoint = &db_break_table[0];
static db_breakpoint_t db_free_breakpoints = 0;
static db_breakpoint_t db_breakpoint_list = 0;
static db_breakpoint_t db_breakpoint_alloc(void);
static void db_breakpoint_free(db_breakpoint_t bkpt);
static void db_delete_breakpoint(vm_map_t map, db_addr_t addr);
static db_breakpoint_t db_find_breakpoint(vm_map_t map, db_addr_t addr);
static void db_list_breakpoints(void);
static void db_set_breakpoint(vm_map_t map, db_addr_t addr, int count);
static 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);
}
static void
db_breakpoint_free(bkpt)
register db_breakpoint_t bkpt;
{
bkpt->link = db_free_breakpoints;
db_free_breakpoints = bkpt;
}
static 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;
}
static 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);
}
static 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);
}
static boolean_t db_breakpoints_inserted = TRUE;
#ifndef BKPT_WRITE
#define BKPT_WRITE(addr, storage) \
do { \
*storage = db_get_value(addr, BKPT_SIZE, FALSE); \
db_put_value(addr, BKPT_SIZE, BKPT_SET(*storage)); \
} while (0)
#endif
#ifndef BKPT_CLEAR
#define BKPT_CLEAR(addr, storage) \
db_put_value(addr, BKPT_SIZE, *storage)
#endif
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_WRITE(bkpt->address, &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)) {
BKPT_CLEAR(bkpt->address, &bkpt->bkpt_inst);
}
db_breakpoints_inserted = FALSE;
}
}
#ifdef SOFTWARE_SSTEP
/*
* 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_WRITE(bkpt->address, &bkpt->bkpt_inst);
return bkpt;
}
void
db_delete_temp_breakpoint(bkpt)
db_breakpoint_t bkpt;
{
BKPT_CLEAR(bkpt->address, &bkpt->bkpt_inst);
db_breakpoint_free(bkpt);
}
#endif /* SOFTWARE_SSTEP */
/*
* List breakpoints.
*/
static 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%8p %5d ",
db_map_current(bkpt->map) ? "*" : " ",
(void *)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;
boolean_t 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;
boolean_t 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(dummy1, dummy2, dummy3, dummy4)
db_expr_t dummy1;
boolean_t dummy2;
db_expr_t dummy3;
char * dummy4;
{
db_list_breakpoints();
}
/*
* 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;
}
#ifdef ALT_BREAK_TO_DEBUGGER
/*
* Solaris implements a new BREAK which is initiated by a character sequence
* CR ~ ^b which is similar to a familiar pattern used on Sun servers by the
* Remote Console.
*
* Note that this function may be called from almost anywhere, with interrupts
* disabled and with unknown locks held, so it must not access data other than
* its arguments. Its up to the caller to ensure that the state variable is
* consistent.
*/
#define KEY_CR 13 /* CR '\r' */
#define KEY_TILDE 126 /* ~ */
#define KEY_CRTLB 2 /* ^B */
int
db_alt_break(int data, int *state)
{
int brk = 0;
switch (data) {
case KEY_CR:
*state = KEY_TILDE;
break;
case KEY_TILDE:
if (*state == KEY_TILDE)
*state = KEY_CRTLB;
else
*state = 0;
break;
case KEY_CRTLB:
if (*state == KEY_CRTLB)
brk = 1;
default:
*state = 0;
break;
}
return (brk);
}
#endif