freebsd-dev/sys/gdb/gdb_main.c
Pedro F. Giffuni 497b6b2a86 sys/gdb: further adoption of SPDX licensing ID tags.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
2017-11-27 15:16:59 +00:00

340 lines
8.0 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (c) 2004 Marcel Moolenaar
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kdb.h>
#include <sys/kernel.h>
#include <sys/pcpu.h>
#include <sys/proc.h>
#include <sys/reboot.h>
#include <machine/gdb_machdep.h>
#include <machine/kdb.h>
#include <gdb/gdb.h>
#include <gdb/gdb_int.h>
static dbbe_init_f gdb_init;
static dbbe_trap_f gdb_trap;
KDB_BACKEND(gdb, gdb_init, NULL, NULL, gdb_trap);
static struct gdb_dbgport null_gdb_dbgport;
DATA_SET(gdb_dbgport_set, null_gdb_dbgport);
SET_DECLARE(gdb_dbgport_set, struct gdb_dbgport);
struct gdb_dbgport *gdb_cur = NULL;
int gdb_listening = 0;
static unsigned char gdb_bindata[64];
static int
gdb_init(void)
{
struct gdb_dbgport *dp, **iter;
int cur_pri, pri;
gdb_cur = NULL;
cur_pri = -1;
SET_FOREACH(iter, gdb_dbgport_set) {
dp = *iter;
pri = (dp->gdb_probe != NULL) ? dp->gdb_probe() : -1;
dp->gdb_active = (pri >= 0) ? 0 : -1;
if (pri > cur_pri) {
cur_pri = pri;
gdb_cur = dp;
}
}
if (gdb_cur != NULL) {
printf("GDB: debug ports:");
SET_FOREACH(iter, gdb_dbgport_set) {
dp = *iter;
if (dp->gdb_active == 0)
printf(" %s", dp->gdb_name);
}
printf("\n");
} else
printf("GDB: no debug ports present\n");
if (gdb_cur != NULL) {
gdb_cur->gdb_init();
printf("GDB: current port: %s\n", gdb_cur->gdb_name);
}
if (gdb_cur != NULL) {
cur_pri = (boothowto & RB_GDB) ? 2 : 0;
gdb_consinit();
} else
cur_pri = -1;
return (cur_pri);
}
static void
gdb_do_mem_search(void)
{
size_t patlen;
intmax_t addr, size;
const unsigned char *found;
if (gdb_rx_varhex(&addr) || gdb_rx_char() != ';' ||
gdb_rx_varhex(&size) || gdb_rx_char() != ';' ||
gdb_rx_bindata(gdb_bindata, sizeof(gdb_bindata), &patlen)) {
gdb_tx_err(EINVAL);
return;
}
if (gdb_search_mem((char *)(uintptr_t)addr, size, gdb_bindata,
patlen, &found)) {
if (found == 0ULL)
gdb_tx_begin('0');
else {
gdb_tx_begin('1');
gdb_tx_char(',');
gdb_tx_hex((intmax_t)(uintptr_t)found, 8);
}
gdb_tx_end();
} else
gdb_tx_err(EIO);
}
static int
gdb_trap(int type, int code)
{
jmp_buf jb;
struct thread *thr_iter;
void *prev_jb;
prev_jb = kdb_jmpbuf(jb);
if (setjmp(jb) != 0) {
printf("%s bailing, hopefully back to ddb!\n", __func__);
gdb_listening = 0;
(void)kdb_jmpbuf(prev_jb);
return (1);
}
gdb_listening = 0;
/*
* Send a T packet. We currently do not support watchpoints (the
* awatch, rwatch or watch elements).
*/
gdb_tx_begin('T');
gdb_tx_hex(gdb_cpu_signal(type, code), 2);
gdb_tx_varhex(GDB_REG_PC);
gdb_tx_char(':');
gdb_tx_reg(GDB_REG_PC);
gdb_tx_char(';');
gdb_tx_str("thread:");
gdb_tx_varhex((long)kdb_thread->td_tid);
gdb_tx_char(';');
gdb_tx_end(); /* XXX check error condition. */
thr_iter = NULL;
while (gdb_rx_begin() == 0) {
/* printf("GDB: got '%s'\n", gdb_rxp); */
switch (gdb_rx_char()) {
case '?': /* Last signal. */
gdb_tx_begin('S');
gdb_tx_hex(gdb_cpu_signal(type, code), 2);
gdb_tx_end();
break;
case 'c': { /* Continue. */
uintmax_t addr;
register_t pc;
if (!gdb_rx_varhex(&addr)) {
pc = addr;
gdb_cpu_setreg(GDB_REG_PC, &pc);
}
kdb_cpu_clear_singlestep();
gdb_listening = 1;
return (1);
}
case 'C': { /* Continue with signal. */
uintmax_t addr, sig;
register_t pc;
if (!gdb_rx_varhex(&sig) && gdb_rx_char() == ';' &&
!gdb_rx_varhex(&addr)) {
pc = addr;
gdb_cpu_setreg(GDB_REG_PC, &pc);
}
kdb_cpu_clear_singlestep();
gdb_listening = 1;
return (1);
}
case 'D': { /* Detach */
gdb_tx_ok();
kdb_cpu_clear_singlestep();
return (1);
}
case 'g': { /* Read registers. */
size_t r;
gdb_tx_begin(0);
for (r = 0; r < GDB_NREGS; r++)
gdb_tx_reg(r);
gdb_tx_end();
break;
}
case 'G': /* Write registers. */
gdb_tx_err(0);
break;
case 'H': { /* Set thread. */
intmax_t tid;
struct thread *thr;
gdb_rx_char();
if (gdb_rx_varhex(&tid)) {
gdb_tx_err(EINVAL);
break;
}
if (tid > 0) {
thr = kdb_thr_lookup(tid);
if (thr == NULL) {
gdb_tx_err(ENOENT);
break;
}
kdb_thr_select(thr);
}
gdb_tx_ok();
break;
}
case 'k': /* Kill request. */
kdb_cpu_clear_singlestep();
gdb_listening = 1;
return (1);
case 'm': { /* Read memory. */
uintmax_t addr, size;
if (gdb_rx_varhex(&addr) || gdb_rx_char() != ',' ||
gdb_rx_varhex(&size)) {
gdb_tx_err(EINVAL);
break;
}
gdb_tx_begin(0);
if (gdb_tx_mem((char *)(uintptr_t)addr, size))
gdb_tx_end();
else
gdb_tx_err(EIO);
break;
}
case 'M': { /* Write memory. */
uintmax_t addr, size;
if (gdb_rx_varhex(&addr) || gdb_rx_char() != ',' ||
gdb_rx_varhex(&size) || gdb_rx_char() != ':') {
gdb_tx_err(EINVAL);
break;
}
if (gdb_rx_mem((char *)(uintptr_t)addr, size) == 0)
gdb_tx_err(EIO);
else
gdb_tx_ok();
break;
}
case 'P': { /* Write register. */
char *val;
uintmax_t reg;
val = gdb_rxp;
if (gdb_rx_varhex(&reg) || gdb_rx_char() != '=' ||
!gdb_rx_mem(val, gdb_cpu_regsz(reg))) {
gdb_tx_err(EINVAL);
break;
}
gdb_cpu_setreg(reg, val);
gdb_tx_ok();
break;
}
case 'q': /* General query. */
if (gdb_rx_equal("fThreadInfo")) {
thr_iter = kdb_thr_first();
gdb_tx_begin('m');
gdb_tx_hex((long)thr_iter->td_tid, 8);
gdb_tx_end();
} else if (gdb_rx_equal("sThreadInfo")) {
if (thr_iter == NULL) {
gdb_tx_err(ENXIO);
break;
}
thr_iter = kdb_thr_next(thr_iter);
if (thr_iter != NULL) {
gdb_tx_begin('m');
gdb_tx_hex((long)thr_iter->td_tid, 8);
gdb_tx_end();
} else {
gdb_tx_begin('l');
gdb_tx_end();
}
} else if (gdb_rx_equal("Search:memory:")) {
gdb_do_mem_search();
} else if (!gdb_cpu_query())
gdb_tx_empty();
break;
case 's': { /* Step. */
uintmax_t addr;
register_t pc;
if (!gdb_rx_varhex(&addr)) {
pc = addr;
gdb_cpu_setreg(GDB_REG_PC, &pc);
}
kdb_cpu_set_singlestep();
gdb_listening = 1;
return (1);
}
case 'S': { /* Step with signal. */
uintmax_t addr, sig;
register_t pc;
if (!gdb_rx_varhex(&sig) && gdb_rx_char() == ';' &&
!gdb_rx_varhex(&addr)) {
pc = addr;
gdb_cpu_setreg(GDB_REG_PC, &pc);
}
kdb_cpu_set_singlestep();
gdb_listening = 1;
return (1);
}
case 'T': { /* Thread alive. */
intmax_t tid;
if (gdb_rx_varhex(&tid)) {
gdb_tx_err(EINVAL);
break;
}
if (kdb_thr_lookup(tid) != NULL)
gdb_tx_ok();
else
gdb_tx_err(ENOENT);
break;
}
case -1:
/* Empty command. Treat as unknown command. */
/* FALLTHROUGH */
default:
/* Unknown command. Send empty response. */
gdb_tx_empty();
break;
}
}
(void)kdb_jmpbuf(prev_jb);
return (0);
}