Google Git
Sign in
qemu / qemu / 72dec1666fe92b5a5932d7f5c26bdfc72e238bcb / . / gdbstub / gdbstub.c
blob: b3574997ea2e9fcf6c80af56fc8a483a59a2e455 [file] [log] [blame]
/*
* gdb server stub
*
* This implements a subset of the remote protocol as described in:
*
* https://sourceware.org/gdb/onlinedocs/gdb/Remote-Protocol.html
*
* Copyright (c) 2003-2005 Fabrice Bellard
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*
* SPDX-License-Identifier: LGPL-2.0+
*/
#include "qemu/osdep.h"
#include "qemu/ctype.h"
#include "qemu/cutils.h"
#include "qemu/module.h"
#include "qemu/error-report.h"
#include "trace.h"
#include "exec/gdbstub.h"
#include "gdbstub/syscalls.h"
#ifdef CONFIG_USER_ONLY
#include "accel/tcg/vcpu-state.h"
#include "gdbstub/user.h"
#else
#include "hw/cpu/cluster.h"
#include "hw/boards.h"
#endif
#include "hw/core/cpu.h"
#include "sysemu/hw_accel.h"
#include "sysemu/runstate.h"
#include "exec/replay-core.h"
#include "exec/hwaddr.h"
#include "internals.h"
typedef struct GDBRegisterState {
int base_reg;
gdb_get_reg_cb get_reg;
gdb_set_reg_cb set_reg;
const GDBFeature *feature;
} GDBRegisterState;
GDBState gdbserver_state;
void gdb_init_gdbserver_state(void)
{
g_assert(!gdbserver_state.init);
memset(&gdbserver_state, 0, sizeof(GDBState));
gdbserver_state.init = true;
gdbserver_state.str_buf = g_string_new(NULL);
gdbserver_state.mem_buf = g_byte_array_sized_new(MAX_PACKET_LENGTH);
gdbserver_state.last_packet = g_byte_array_sized_new(MAX_PACKET_LENGTH + 4);
/*
* What single-step modes are supported is accelerator dependent.
* By default try to use no IRQs and no timers while single
* stepping so as to make single stepping like a typical ICE HW step.
*/
gdbserver_state.supported_sstep_flags = accel_supported_gdbstub_sstep_flags();
gdbserver_state.sstep_flags = SSTEP_ENABLE | SSTEP_NOIRQ | SSTEP_NOTIMER;
gdbserver_state.sstep_flags &= gdbserver_state.supported_sstep_flags;
}
/* writes 2*len+1 bytes in buf */
void gdb_memtohex(GString *buf, const uint8_t *mem, int len)
{
int i, c;
for(i = 0; i < len; i++) {
c = mem[i];
g_string_append_c(buf, tohex(c >> 4));
g_string_append_c(buf, tohex(c & 0xf));
}
g_string_append_c(buf, '\0');
}
void gdb_hextomem(GByteArray *mem, const char *buf, int len)
{
int i;
for(i = 0; i < len; i++) {
guint8 byte = fromhex(buf[0]) << 4 | fromhex(buf[1]);
g_byte_array_append(mem, &byte, 1);
buf += 2;
}
}
static void hexdump(const char *buf, int len,
void (*trace_fn)(size_t ofs, char const *text))
{
char line_buffer[3 * 16 + 4 + 16 + 1];
size_t i;
for (i = 0; i < len || (i & 0xF); ++i) {
size_t byte_ofs = i & 15;
if (byte_ofs == 0) {
memset(line_buffer, ' ', 3 * 16 + 4 + 16);
line_buffer[3 * 16 + 4 + 16] = 0;
}
size_t col_group = (i >> 2) & 3;
size_t hex_col = byte_ofs * 3 + col_group;
size_t txt_col = 3 * 16 + 4 + byte_ofs;
if (i < len) {
char value = buf[i];
line_buffer[hex_col + 0] = tohex((value >> 4) & 0xF);
line_buffer[hex_col + 1] = tohex((value >> 0) & 0xF);
line_buffer[txt_col + 0] = (value >= ' ' && value < 127)
? value
: '.';
}
if (byte_ofs == 0xF)
trace_fn(i & -16, line_buffer);
}
}
/* return -1 if error, 0 if OK */
int gdb_put_packet_binary(const char *buf, int len, bool dump)
{
int csum, i;
uint8_t footer[3];
if (dump && trace_event_get_state_backends(TRACE_GDBSTUB_IO_BINARYREPLY)) {
hexdump(buf, len, trace_gdbstub_io_binaryreply);
}
for(;;) {
g_byte_array_set_size(gdbserver_state.last_packet, 0);
g_byte_array_append(gdbserver_state.last_packet,
(const uint8_t *) "$", 1);
g_byte_array_append(gdbserver_state.last_packet,
(const uint8_t *) buf, len);
csum = 0;
for(i = 0; i < len; i++) {
csum += buf[i];
}
footer[0] = '#';
footer[1] = tohex((csum >> 4) & 0xf);
footer[2] = tohex((csum) & 0xf);
g_byte_array_append(gdbserver_state.last_packet, footer, 3);
gdb_put_buffer(gdbserver_state.last_packet->data,
gdbserver_state.last_packet->len);
if (gdb_got_immediate_ack()) {
break;
}
}
return 0;
}
/* return -1 if error, 0 if OK */
int gdb_put_packet(const char *buf)
{
trace_gdbstub_io_reply(buf);
return gdb_put_packet_binary(buf, strlen(buf), false);
}
void gdb_put_strbuf(void)
{
gdb_put_packet(gdbserver_state.str_buf->str);
}
/* Encode data using the encoding for 'x' packets. */
void gdb_memtox(GString *buf, const char *mem, int len)
{
char c;
while (len--) {
c = *(mem++);
switch (c) {
case '#': case '$': case '*': case '}':
g_string_append_c(buf, '}');
g_string_append_c(buf, c ^ 0x20);
break;
default:
g_string_append_c(buf, c);
break;
}
}
}
static uint32_t gdb_get_cpu_pid(CPUState *cpu)
{
#ifdef CONFIG_USER_ONLY
return getpid();
#else
if (cpu->cluster_index == UNASSIGNED_CLUSTER_INDEX) {
/* Return the default process' PID */
int index = gdbserver_state.process_num - 1;
return gdbserver_state.processes[index].pid;
}
return cpu->cluster_index + 1;
#endif
}
GDBProcess *gdb_get_process(uint32_t pid)
{
int i;
if (!pid) {
/* 0 means any process, we take the first one */
return &gdbserver_state.processes[0];
}
for (i = 0; i < gdbserver_state.process_num; i++) {
if (gdbserver_state.processes[i].pid == pid) {
return &gdbserver_state.processes[i];
}
}
return NULL;
}
static GDBProcess *gdb_get_cpu_process(CPUState *cpu)
{
return gdb_get_process(gdb_get_cpu_pid(cpu));
}
static CPUState *find_cpu(uint32_t thread_id)
{
CPUState *cpu;
CPU_FOREACH(cpu) {
if (gdb_get_cpu_index(cpu) == thread_id) {
return cpu;
}
}
return NULL;
}
CPUState *gdb_get_first_cpu_in_process(GDBProcess *process)
{
CPUState *cpu;
CPU_FOREACH(cpu) {
if (gdb_get_cpu_pid(cpu) == process->pid) {
return cpu;
}
}
return NULL;
}
static CPUState *gdb_next_cpu_in_process(CPUState *cpu)
{
uint32_t pid = gdb_get_cpu_pid(cpu);
cpu = CPU_NEXT(cpu);
while (cpu) {
if (gdb_get_cpu_pid(cpu) == pid) {
break;
}
cpu = CPU_NEXT(cpu);
}
return cpu;
}
/* Return the cpu following @cpu, while ignoring unattached processes. */
static CPUState *gdb_next_attached_cpu(CPUState *cpu)
{
cpu = CPU_NEXT(cpu);
while (cpu) {
if (gdb_get_cpu_process(cpu)->attached) {
break;
}
cpu = CPU_NEXT(cpu);
}
return cpu;
}
/* Return the first attached cpu */
CPUState *gdb_first_attached_cpu(void)
{
CPUState *cpu = first_cpu;
GDBProcess *process = gdb_get_cpu_process(cpu);
if (!process->attached) {
return gdb_next_attached_cpu(cpu);
}
return cpu;
}
static CPUState *gdb_get_cpu(uint32_t pid, uint32_t tid)
{
GDBProcess *process;
CPUState *cpu;
if (!pid && !tid) {
/* 0 means any process/thread, we take the first attached one */
return gdb_first_attached_cpu();
} else if (pid && !tid) {
/* any thread in a specific process */
process = gdb_get_process(pid);
if (process == NULL) {
return NULL;
}
if (!process->attached) {
return NULL;
}
return gdb_get_first_cpu_in_process(process);
} else {
/* a specific thread */
cpu = find_cpu(tid);
if (cpu == NULL) {
return NULL;
}
process = gdb_get_cpu_process(cpu);
if (pid && process->pid != pid) {
return NULL;
}
if (!process->attached) {
return NULL;
}
return cpu;
}
}
static const char *get_feature_xml(const char *p, const char **newp,
GDBProcess *process)
{
CPUState *cpu = gdb_get_first_cpu_in_process(process);
CPUClass *cc = CPU_GET_CLASS(cpu);
GDBRegisterState *r;
size_t len;
/*
* qXfer:features:read:ANNEX:OFFSET,LENGTH'
* ^p ^newp
*/
char *term = strchr(p, ':');
*newp = term + 1;
len = term - p;
/* Is it the main target xml? */
if (strncmp(p, "target.xml", len) == 0) {
if (!process->target_xml) {
g_autoptr(GPtrArray) xml = g_ptr_array_new_with_free_func(g_free);
g_ptr_array_add(
xml,
g_strdup("<?xml version=\"1.0\"?>"
"<!DOCTYPE target SYSTEM \"gdb-target.dtd\">"
"<target>"));
if (cc->gdb_arch_name) {
g_ptr_array_add(
xml,
g_markup_printf_escaped("<architecture>%s</architecture>",
cc->gdb_arch_name(cpu)));
}
for (guint i = 0; i < cpu->gdb_regs->len; i++) {
r = &g_array_index(cpu->gdb_regs, GDBRegisterState, i);
g_ptr_array_add(
xml,
g_markup_printf_escaped("<xi:include href=\"%s\"/>",
r->feature->xmlname));
}
g_ptr_array_add(xml, g_strdup("</target>"));
g_ptr_array_add(xml, NULL);
process->target_xml = g_strjoinv(NULL, (void *)xml->pdata);
}
return process->target_xml;
}
/* Is it one of the features? */
for (guint i = 0; i < cpu->gdb_regs->len; i++) {
r = &g_array_index(cpu->gdb_regs, GDBRegisterState, i);
if (strncmp(p, r->feature->xmlname, len) == 0) {
return r->feature->xml;
}
}
/* failed */
return NULL;
}
void gdb_feature_builder_init(GDBFeatureBuilder *builder, GDBFeature *feature,
const char *name, const char *xmlname,
int base_reg)
{
char *header = g_markup_printf_escaped(
"<?xml version=\"1.0\"?>"
"<!DOCTYPE feature SYSTEM \"gdb-target.dtd\">"
"<feature name=\"%s\">",
name);
builder->feature = feature;
builder->xml = g_ptr_array_new();
g_ptr_array_add(builder->xml, header);
builder->regs = g_ptr_array_new();
builder->base_reg = base_reg;
feature->xmlname = xmlname;
feature->name = name;
}
void gdb_feature_builder_append_tag(const GDBFeatureBuilder *builder,
const char *format, ...)
{
va_list ap;
va_start(ap, format);
g_ptr_array_add(builder->xml, g_markup_vprintf_escaped(format, ap));
va_end(ap);
}
void gdb_feature_builder_append_reg(const GDBFeatureBuilder *builder,
const char *name,
int bitsize,
int regnum,
const char *type,
const char *group)
{
if (builder->regs->len <= regnum) {
g_ptr_array_set_size(builder->regs, regnum + 1);
}
builder->regs->pdata[regnum] = (gpointer *)name;
if (group) {
gdb_feature_builder_append_tag(
builder,
"<reg name=\"%s\" bitsize=\"%d\" regnum=\"%d\" type=\"%s\" group=\"%s\"/>",
name, bitsize, builder->base_reg + regnum, type, group);
} else {
gdb_feature_builder_append_tag(
builder,
"<reg name=\"%s\" bitsize=\"%d\" regnum=\"%d\" type=\"%s\"/>",
name, bitsize, builder->base_reg + regnum, type);
}
}
void gdb_feature_builder_end(const GDBFeatureBuilder *builder)
{
g_ptr_array_add(builder->xml, (void *)"</feature>");
g_ptr_array_add(builder->xml, NULL);
builder->feature->xml = g_strjoinv(NULL, (void *)builder->xml->pdata);
for (guint i = 0; i < builder->xml->len - 2; i++) {
g_free(g_ptr_array_index(builder->xml, i));
}
g_ptr_array_free(builder->xml, TRUE);
builder->feature->num_regs = builder->regs->len;
builder->feature->regs = (void *)g_ptr_array_free(builder->regs, FALSE);
}
const GDBFeature *gdb_find_static_feature(const char *xmlname)
{
const GDBFeature *feature;
for (feature = gdb_static_features; feature->xmlname; feature++) {
if (!strcmp(feature->xmlname, xmlname)) {
return feature;
}
}
g_assert_not_reached();
}
GArray *gdb_get_register_list(CPUState *cpu)
{
GArray *results = g_array_new(true, true, sizeof(GDBRegDesc));
/* registers are only available once the CPU is initialised */
if (!cpu->gdb_regs) {
return results;
}
for (int f = 0; f < cpu->gdb_regs->len; f++) {
GDBRegisterState *r = &g_array_index(cpu->gdb_regs, GDBRegisterState, f);
for (int i = 0; i < r->feature->num_regs; i++) {
const char *name = r->feature->regs[i];
GDBRegDesc desc = {
r->base_reg + i,
name,
r->feature->name
};
g_array_append_val(results, desc);
}
}
return results;
}
int gdb_read_register(CPUState *cpu, GByteArray *buf, int reg)
{
CPUClass *cc = CPU_GET_CLASS(cpu);
GDBRegisterState *r;
if (reg < cc->gdb_num_core_regs) {
return cc->gdb_read_register(cpu, buf, reg);
}
for (guint i = 0; i < cpu->gdb_regs->len; i++) {
r = &g_array_index(cpu->gdb_regs, GDBRegisterState, i);
if (r->base_reg <= reg && reg < r->base_reg + r->feature->num_regs) {
return r->get_reg(cpu, buf, reg - r->base_reg);
}
}
return 0;
}
static int gdb_write_register(CPUState *cpu, uint8_t *mem_buf, int reg)
{
CPUClass *cc = CPU_GET_CLASS(cpu);
GDBRegisterState *r;
if (reg < cc->gdb_num_core_regs) {
return cc->gdb_write_register(cpu, mem_buf, reg);
}
for (guint i = 0; i < cpu->gdb_regs->len; i++) {
r = &g_array_index(cpu->gdb_regs, GDBRegisterState, i);
if (r->base_reg <= reg && reg < r->base_reg + r->feature->num_regs) {
return r->set_reg(cpu, mem_buf, reg - r->base_reg);
}
}
return 0;
}
static void gdb_register_feature(CPUState *cpu, int base_reg,
gdb_get_reg_cb get_reg, gdb_set_reg_cb set_reg,
const GDBFeature *feature)
{
GDBRegisterState s = {
.base_reg = base_reg,
.get_reg = get_reg,
.set_reg = set_reg,
.feature = feature
};
g_array_append_val(cpu->gdb_regs, s);
}
void gdb_init_cpu(CPUState *cpu)
{
CPUClass *cc = CPU_GET_CLASS(cpu);
const GDBFeature *feature;
cpu->gdb_regs = g_array_new(false, false, sizeof(GDBRegisterState));
if (cc->gdb_core_xml_file) {
feature = gdb_find_static_feature(cc->gdb_core_xml_file);
gdb_register_feature(cpu, 0,
cc->gdb_read_register, cc->gdb_write_register,
feature);
cpu->gdb_num_regs = cpu->gdb_num_g_regs = feature->num_regs;
}
if (cc->gdb_num_core_regs) {
cpu->gdb_num_regs = cpu->gdb_num_g_regs = cc->gdb_num_core_regs;
}
}
void gdb_register_coprocessor(CPUState *cpu,
gdb_get_reg_cb get_reg, gdb_set_reg_cb set_reg,
const GDBFeature *feature, int g_pos)
{
GDBRegisterState *s;
guint i;
int base_reg = cpu->gdb_num_regs;
for (i = 0; i < cpu->gdb_regs->len; i++) {
/* Check for duplicates. */
s = &g_array_index(cpu->gdb_regs, GDBRegisterState, i);
if (s->feature == feature) {
return;
}
}
gdb_register_feature(cpu, base_reg, get_reg, set_reg, feature);
/* Add to end of list. */
cpu->gdb_num_regs += feature->num_regs;
if (g_pos) {
if (g_pos != base_reg) {
error_report("Error: Bad gdb register numbering for '%s', "
"expected %d got %d", feature->xml, g_pos, base_reg);
} else {
cpu->gdb_num_g_regs = cpu->gdb_num_regs;
}
}
}
static void gdb_process_breakpoint_remove_all(GDBProcess *p)
{
CPUState *cpu = gdb_get_first_cpu_in_process(p);
while (cpu) {
gdb_breakpoint_remove_all(cpu);
cpu = gdb_next_cpu_in_process(cpu);
}
}
static void gdb_set_cpu_pc(vaddr pc)
{
CPUState *cpu = gdbserver_state.c_cpu;
cpu_synchronize_state(cpu);
cpu_set_pc(cpu, pc);
}
void gdb_append_thread_id(CPUState *cpu, GString *buf)
{
if (gdbserver_state.multiprocess) {
g_string_append_printf(buf, "p%02x.%02x",
gdb_get_cpu_pid(cpu), gdb_get_cpu_index(cpu));
} else {
g_string_append_printf(buf, "%02x", gdb_get_cpu_index(cpu));
}
}
static GDBThreadIdKind read_thread_id(const char *buf, const char **end_buf,
uint32_t *pid, uint32_t *tid)
{
unsigned long p, t;
int ret;
if (*buf == 'p') {
buf++;
ret = qemu_strtoul(buf, &buf, 16, &p);
if (ret) {
return GDB_READ_THREAD_ERR;
}
/* Skip '.' */
buf++;
} else {
p = 0;
}
ret = qemu_strtoul(buf, &buf, 16, &t);
if (ret) {
return GDB_READ_THREAD_ERR;
}
*end_buf = buf;
if (p == -1) {
return GDB_ALL_PROCESSES;
}
if (pid) {
*pid = p;
}
if (t == -1) {
return GDB_ALL_THREADS;
}
if (tid) {
*tid = t;
}
return GDB_ONE_THREAD;
}
/**
* gdb_handle_vcont - Parses and handles a vCont packet.
* returns -ENOTSUP if a command is unsupported, -EINVAL or -ERANGE if there is
* a format error, 0 on success.
*/
static int gdb_handle_vcont(const char *p)
{
int res, signal = 0;
char cur_action;
unsigned long tmp;
uint32_t pid, tid;
GDBProcess *process;
CPUState *cpu;
GDBThreadIdKind kind;
unsigned int max_cpus = gdb_get_max_cpus();
/* uninitialised CPUs stay 0 */
g_autofree char *newstates = g_new0(char, max_cpus);
/* mark valid CPUs with 1 */
CPU_FOREACH(cpu) {
newstates[cpu->cpu_index] = 1;
}
/*
* res keeps track of what error we are returning, with -ENOTSUP meaning
* that the command is unknown or unsupported, thus returning an empty
* packet, while -EINVAL and -ERANGE cause an E22 packet, due to invalid,
* or incorrect parameters passed.
*/
res = 0;
/*
* target_count and last_target keep track of how many CPUs we are going to
* step or resume, and a pointer to the state structure of one of them,
* respectively
*/
int target_count = 0;
CPUState *last_target = NULL;
while (*p) {
if (*p++ != ';') {
return -ENOTSUP;
}
cur_action = *p++;
if (cur_action == 'C' || cur_action == 'S') {
cur_action = qemu_tolower(cur_action);
res = qemu_strtoul(p, &p, 16, &tmp);
if (res) {
return res;
}
signal = gdb_signal_to_target(tmp);
} else if (cur_action != 'c' && cur_action != 's') {
/* unknown/invalid/unsupported command */
return -ENOTSUP;
}
if (*p == '\0' || *p == ';') {
/*
* No thread specifier, action is on "all threads". The
* specification is unclear regarding the process to act on. We
* choose all processes.
*/
kind = GDB_ALL_PROCESSES;
} else if (*p++ == ':') {
kind = read_thread_id(p, &p, &pid, &tid);
} else {
return -ENOTSUP;
}
switch (kind) {
case GDB_READ_THREAD_ERR:
return -EINVAL;
case GDB_ALL_PROCESSES:
cpu = gdb_first_attached_cpu();
while (cpu) {
if (newstates[cpu->cpu_index] == 1) {
newstates[cpu->cpu_index] = cur_action;
target_count++;
last_target = cpu;
}
cpu = gdb_next_attached_cpu(cpu);
}
break;
case GDB_ALL_THREADS:
process = gdb_get_process(pid);
if (!process->attached) {
return -EINVAL;
}
cpu = gdb_get_first_cpu_in_process(process);
while (cpu) {
if (newstates[cpu->cpu_index] == 1) {
newstates[cpu->cpu_index] = cur_action;
target_count++;
last_target = cpu;
}
cpu = gdb_next_cpu_in_process(cpu);
}
break;
case GDB_ONE_THREAD:
cpu = gdb_get_cpu(pid, tid);
/* invalid CPU/thread specified */
if (!cpu) {
return -EINVAL;
}
/* only use if no previous match occourred */
if (newstates[cpu->cpu_index] == 1) {
newstates[cpu->cpu_index] = cur_action;
target_count++;
last_target = cpu;
}
break;
}
}
/*
* if we're about to resume a specific set of CPUs/threads, make it so that
* in case execution gets interrupted, we can send GDB a stop reply with a
* correct value. it doesn't really matter which CPU we tell GDB the signal
* happened in (VM pauses stop all of them anyway), so long as it is one of
* the ones we resumed/single stepped here.
*/
if (target_count > 0) {
gdbserver_state.c_cpu = last_target;
}
gdbserver_state.signal = signal;
gdb_continue_partial(newstates);
return res;
}
static const char *cmd_next_param(const char *param, const char delimiter)
{
static const char all_delimiters[] = ",;:=";
char curr_delimiters[2] = {0};
const char *delimiters;
if (delimiter == '?') {
delimiters = all_delimiters;
} else if (delimiter == '0') {
return strchr(param, '\0');
} else if (delimiter == '.' && *param) {
return param + 1;
} else {
curr_delimiters[0] = delimiter;
delimiters = curr_delimiters;
}
param += strcspn(param, delimiters);
if (*param) {
param++;
}
return param;
}
static int cmd_parse_params(const char *data, const char *schema,
GArray *params)
{
const char *curr_schema, *curr_data;
g_assert(schema);
g_assert(params->len == 0);
curr_schema = schema;
curr_data = data;
while (curr_schema[0] && curr_schema[1] && *curr_data) {
GdbCmdVariant this_param;
switch (curr_schema[0]) {
case 'l':
if (qemu_strtoul(curr_data, &curr_data, 16,
&this_param.val_ul)) {
return -EINVAL;
}
curr_data = cmd_next_param(curr_data, curr_schema[1]);
g_array_append_val(params, this_param);
break;
case 'L':
if (qemu_strtou64(curr_data, &curr_data, 16,
(uint64_t *)&this_param.val_ull)) {
return -EINVAL;
}
curr_data = cmd_next_param(curr_data, curr_schema[1]);
g_array_append_val(params, this_param);
break;
case 's':
this_param.data = curr_data;
curr_data = cmd_next_param(curr_data, curr_schema[1]);
g_array_append_val(params, this_param);
break;
case 'o':
this_param.opcode = *(uint8_t *)curr_data;
curr_data = cmd_next_param(curr_data, curr_schema[1]);
g_array_append_val(params, this_param);
break;
case 't':
this_param.thread_id.kind =
read_thread_id(curr_data, &curr_data,
&this_param.thread_id.pid,
&this_param.thread_id.tid);
curr_data = cmd_next_param(curr_data, curr_schema[1]);
g_array_append_val(params, this_param);
break;
case '?':
curr_data = cmd_next_param(curr_data, curr_schema[1]);
break;
default:
return -EINVAL;
}
curr_schema += 2;
}
return 0;
}
typedef void (*GdbCmdHandler)(GArray *params, void *user_ctx);
/*
* cmd_startswith -> cmd is compared using startswith
*
* allow_stop_reply -> true iff the gdbstub can respond to this command with a
* "stop reply" packet. The list of commands that accept such response is
* defined at the GDB Remote Serial Protocol documentation. see:
* https://sourceware.org/gdb/onlinedocs/gdb/Stop-Reply-Packets.html#Stop-Reply-Packets.
*
* schema definitions:
* Each schema parameter entry consists of 2 chars,
* the first char represents the parameter type handling
* the second char represents the delimiter for the next parameter
*
* Currently supported schema types:
* 'l' -> unsigned long (stored in .val_ul)
* 'L' -> unsigned long long (stored in .val_ull)
* 's' -> string (stored in .data)
* 'o' -> single char (stored in .opcode)
* 't' -> thread id (stored in .thread_id)
* '?' -> skip according to delimiter
*
* Currently supported delimiters:
* '?' -> Stop at any delimiter (",;:=\0")
* '0' -> Stop at "\0"
* '.' -> Skip 1 char unless reached "\0"
* Any other value is treated as the delimiter value itself
*/
typedef struct GdbCmdParseEntry {
GdbCmdHandler handler;
const char *cmd;
bool cmd_startswith;
const char *schema;
bool allow_stop_reply;
} GdbCmdParseEntry;
static inline int startswith(const char *string, const char *pattern)
{
return !strncmp(string, pattern, strlen(pattern));
}
static int process_string_cmd(const char *data,
const GdbCmdParseEntry *cmds, int num_cmds)
{
int i;
g_autoptr(GArray) params = g_array_new(false, true, sizeof(GdbCmdVariant));
if (!cmds) {
return -1;
}
for (i = 0; i < num_cmds; i++) {
const GdbCmdParseEntry *cmd = &cmds[i];
g_assert(cmd->handler && cmd->cmd);
if ((cmd->cmd_startswith && !startswith(data, cmd->cmd)) ||
(!cmd->cmd_startswith && strcmp(cmd->cmd, data))) {
continue;
}
if (cmd->schema) {
if (cmd_parse_params(&data[strlen(cmd->cmd)],
cmd->schema, params)) {
return -1;
}
}
gdbserver_state.allow_stop_reply = cmd->allow_stop_reply;
cmd->handler(params, NULL);
return 0;
}
return -1;
}
static void run_cmd_parser(const char *data, const GdbCmdParseEntry *cmd)
{
if (!data) {
return;
}
g_string_set_size(gdbserver_state.str_buf, 0);
g_byte_array_set_size(gdbserver_state.mem_buf, 0);
/* In case there was an error during the command parsing we must
* send a NULL packet to indicate the command is not supported */
if (process_string_cmd(data, cmd, 1)) {
gdb_put_packet("");
}
}
static void handle_detach(GArray *params, void *user_ctx)
{
GDBProcess *process;
uint32_t pid = 1;
if (gdbserver_state.multiprocess) {
if (!params->len) {
gdb_put_packet("E22");
return;
}
pid = get_param(params, 0)->val_ul;
}
#ifdef CONFIG_USER_ONLY
if (gdb_handle_detach_user(pid)) {
return;
}
#endif
process = gdb_get_process(pid);
gdb_process_breakpoint_remove_all(process);
process->attached = false;
if (pid == gdb_get_cpu_pid(gdbserver_state.c_cpu)) {
gdbserver_state.c_cpu = gdb_first_attached_cpu();
}
if (pid == gdb_get_cpu_pid(gdbserver_state.g_cpu)) {
gdbserver_state.g_cpu = gdb_first_attached_cpu();
}
if (!gdbserver_state.c_cpu) {
/* No more process attached */
gdb_disable_syscalls();
gdb_continue();
}
gdb_put_packet("OK");
}
static void handle_thread_alive(GArray *params, void *user_ctx)
{
CPUState *cpu;
if (!params->len) {
gdb_put_packet("E22");
return;
}
if (get_param(params, 0)->thread_id.kind == GDB_READ_THREAD_ERR) {
gdb_put_packet("E22");
return;
}
cpu = gdb_get_cpu(get_param(params, 0)->thread_id.pid,
get_param(params, 0)->thread_id.tid);
if (!cpu) {
gdb_put_packet("E22");
return;
}
gdb_put_packet("OK");
}
static void handle_continue(GArray *params, void *user_ctx)
{
if (params->len) {
gdb_set_cpu_pc(get_param(params, 0)->val_ull);
}
gdbserver_state.signal = 0;
gdb_continue();
}
static void handle_cont_with_sig(GArray *params, void *user_ctx)
{
unsigned long signal = 0;
/*
* Note: C sig;[addr] is currently unsupported and we simply
* omit the addr parameter
*/
if (params->len) {
signal = get_param(params, 0)->val_ul;
}
gdbserver_state.signal = gdb_signal_to_target(signal);
if (gdbserver_state.signal == -1) {
gdbserver_state.signal = 0;
}
gdb_continue();
}
static void handle_set_thread(GArray *params, void *user_ctx)
{
uint32_t pid, tid;
CPUState *cpu;
if (params->len != 2) {
gdb_put_packet("E22");
return;
}
if (get_param(params, 1)->thread_id.kind == GDB_READ_THREAD_ERR) {
gdb_put_packet("E22");
return;
}
if (get_param(params, 1)->thread_id.kind != GDB_ONE_THREAD) {
gdb_put_packet("OK");
return;
}
pid = get_param(params, 1)->thread_id.pid;
tid = get_param(params, 1)->thread_id.tid;
#ifdef CONFIG_USER_ONLY
if (gdb_handle_set_thread_user(pid, tid)) {
return;
}
#endif
cpu = gdb_get_cpu(pid, tid);
if (!cpu) {
gdb_put_packet("E22");
return;
}
/*
* Note: This command is deprecated and modern gdb's will be using the
* vCont command instead.
*/
switch (get_param(params, 0)->opcode) {
case 'c':
gdbserver_state.c_cpu = cpu;
gdb_put_packet("OK");
break;
case 'g':
gdbserver_state.g_cpu = cpu;
gdb_put_packet("OK");
break;
default:
gdb_put_packet("E22");
break;
}
}
static void handle_insert_bp(GArray *params, void *user_ctx)
{
int res;
if (params->len != 3) {
gdb_put_packet("E22");
return;
}
res = gdb_breakpoint_insert(gdbserver_state.c_cpu,
get_param(params, 0)->val_ul,
get_param(params, 1)->val_ull,
get_param(params, 2)->val_ull);
if (res >= 0) {
gdb_put_packet("OK");
return;
} else if (res == -ENOSYS) {
gdb_put_packet("");
return;
}
gdb_put_packet("E22");
}
static void handle_remove_bp(GArray *params, void *user_ctx)
{
int res;
if (params->len != 3) {
gdb_put_packet("E22");
return;
}
res = gdb_breakpoint_remove(gdbserver_state.c_cpu,
get_param(params, 0)->val_ul,
get_param(params, 1)->val_ull,
get_param(params, 2)->val_ull);
if (res >= 0) {
gdb_put_packet("OK");
return;
} else if (res == -ENOSYS) {
gdb_put_packet("");
return;
}
gdb_put_packet("E22");
}
/*
* handle_set/get_reg
*
* Older gdb are really dumb, and don't use 'G/g' if 'P/p' is available.
* This works, but can be very slow. Anything new enough to understand
* XML also knows how to use this properly. However to use this we
* need to define a local XML file as well as be talking to a
* reasonably modern gdb. Responding with an empty packet will cause
* the remote gdb to fallback to older methods.
*/
static void handle_set_reg(GArray *params, void *user_ctx)
{
int reg_size;
if (params->len != 2) {
gdb_put_packet("E22");
return;
}
reg_size = strlen(get_param(params, 1)->data) / 2;
gdb_hextomem(gdbserver_state.mem_buf, get_param(params, 1)->data, reg_size);
gdb_write_register(gdbserver_state.g_cpu, gdbserver_state.mem_buf->data,
get_param(params, 0)->val_ull);
gdb_put_packet("OK");
}
static void handle_get_reg(GArray *params, void *user_ctx)
{
int reg_size;
if (!params->len) {
gdb_put_packet("E14");
return;
}
reg_size = gdb_read_register(gdbserver_state.g_cpu,
gdbserver_state.mem_buf,
get_param(params, 0)->val_ull);
if (!reg_size) {
gdb_put_packet("E14");
return;
} else {
g_byte_array_set_size(gdbserver_state.mem_buf, reg_size);
}
gdb_memtohex(gdbserver_state.str_buf,
gdbserver_state.mem_buf->data, reg_size);
gdb_put_strbuf();
}
static void handle_write_mem(GArray *params, void *user_ctx)
{
if (params->len != 3) {
gdb_put_packet("E22");
return;
}
/* gdb_hextomem() reads 2*len bytes */
if (get_param(params, 1)->val_ull >
strlen(get_param(params, 2)->data) / 2) {
gdb_put_packet("E22");
return;
}
gdb_hextomem(gdbserver_state.mem_buf, get_param(params, 2)->data,
get_param(params, 1)->val_ull);
if (gdb_target_memory_rw_debug(gdbserver_state.g_cpu,
get_param(params, 0)->val_ull,
gdbserver_state.mem_buf->data,
gdbserver_state.mem_buf->len, true)) {
gdb_put_packet("E14");
return;
}
gdb_put_packet("OK");
}
static void handle_read_mem(GArray *params, void *user_ctx)
{
if (params->len != 2) {
gdb_put_packet("E22");
return;
}
/* gdb_memtohex() doubles the required space */
if (get_param(params, 1)->val_ull > MAX_PACKET_LENGTH / 2) {
gdb_put_packet("E22");
return;
}
g_byte_array_set_size(gdbserver_state.mem_buf,
get_param(params, 1)->val_ull);
if (gdb_target_memory_rw_debug(gdbserver_state.g_cpu,
get_param(params, 0)->val_ull,
gdbserver_state.mem_buf->data,
gdbserver_state.mem_buf->len, false)) {
gdb_put_packet("E14");
return;
}
gdb_memtohex(gdbserver_state.str_buf, gdbserver_state.mem_buf->data,
gdbserver_state.mem_buf->len);
gdb_put_strbuf();
}
static void handle_write_all_regs(GArray *params, void *user_ctx)
{
int reg_id;
size_t len;
uint8_t *registers;
int reg_size;
if (!params->len) {
return;
}
cpu_synchronize_state(gdbserver_state.g_cpu);
len = strlen(get_param(params, 0)->data) / 2;
gdb_hextomem(gdbserver_state.mem_buf, get_param(params, 0)->data, len);
registers = gdbserver_state.mem_buf->data;
for (reg_id = 0;
reg_id < gdbserver_state.g_cpu->gdb_num_g_regs && len > 0;
reg_id++) {
reg_size = gdb_write_register(gdbserver_state.g_cpu, registers, reg_id);
len -= reg_size;
registers += reg_size;
}
gdb_put_packet("OK");
}
static void handle_read_all_regs(GArray *params, void *user_ctx)
{
int reg_id;
size_t len;
cpu_synchronize_state(gdbserver_state.g_cpu);
g_byte_array_set_size(gdbserver_state.mem_buf, 0);
len = 0;
for (reg_id = 0; reg_id < gdbserver_state.g_cpu->gdb_num_g_regs; reg_id++) {
len += gdb_read_register(gdbserver_state.g_cpu,
gdbserver_state.mem_buf,
reg_id);
}
g_assert(len == gdbserver_state.mem_buf->len);
gdb_memtohex(gdbserver_state.str_buf, gdbserver_state.mem_buf->data, len);
gdb_put_strbuf();
}
static void handle_step(GArray *params, void *user_ctx)
{
if (params->len) {
gdb_set_cpu_pc(get_param(params, 0)->val_ull);
}
cpu_single_step(gdbserver_state.c_cpu, gdbserver_state.sstep_flags);
gdb_continue();
}
static void handle_backward(GArray *params, void *user_ctx)
{
if (!gdb_can_reverse()) {
gdb_put_packet("E22");
}
if (params->len == 1) {
switch (get_param(params, 0)->opcode) {
case 's':
if (replay_reverse_step()) {
gdb_continue();
} else {
gdb_put_packet("E14");
}
return;
case 'c':
if (replay_reverse_continue()) {
gdb_continue();
} else {
gdb_put_packet("E14");
}
return;
}
}
/* Default invalid command */
gdb_put_packet("");
}
static void handle_v_cont_query(GArray *params, void *user_ctx)
{
gdb_put_packet("vCont;c;C;s;S");
}
static void handle_v_cont(GArray *params, void *user_ctx)
{
int res;
if (!params->len) {
return;
}
res = gdb_handle_vcont(get_param(params, 0)->data);
if ((res == -EINVAL) || (res == -ERANGE)) {
gdb_put_packet("E22");
} else if (res) {
gdb_put_packet("");
}
}
static void handle_v_attach(GArray *params, void *user_ctx)
{
GDBProcess *process;
CPUState *cpu;
g_string_assign(gdbserver_state.str_buf, "E22");
if (!params->len) {
goto cleanup;
}
process = gdb_get_process(get_param(params, 0)->val_ul);
if (!process) {
goto cleanup;
}
cpu = gdb_get_first_cpu_in_process(process);
if (!cpu) {
goto cleanup;
}
process->attached = true;
gdbserver_state.g_cpu = cpu;
gdbserver_state.c_cpu = cpu;
if (gdbserver_state.allow_stop_reply) {
g_string_printf(gdbserver_state.str_buf, "T%02xthread:", GDB_SIGNAL_TRAP);
gdb_append_thread_id(cpu, gdbserver_state.str_buf);
g_string_append_c(gdbserver_state.str_buf, ';');
gdbserver_state.allow_stop_reply = false;
cleanup:
gdb_put_strbuf();
}
}
static void handle_v_kill(GArray *params, void *user_ctx)
{
/* Kill the target */
gdb_put_packet("OK");
error_report("QEMU: Terminated via GDBstub");
gdb_exit(0);
gdb_qemu_exit(0);
}
static const GdbCmdParseEntry gdb_v_commands_table[] = {
/* Order is important if has same prefix */
{
.handler = handle_v_cont_query,
.cmd = "Cont?",
.cmd_startswith = 1
},
{
.handler = handle_v_cont,
.cmd = "Cont",
.cmd_startswith = 1,
.allow_stop_reply = true,
.schema = "s0"
},
{
.handler = handle_v_attach,
.cmd = "Attach;",
.cmd_startswith = 1,
.allow_stop_reply = true,
.schema = "l0"
},
{
.handler = handle_v_kill,
.cmd = "Kill;",
.cmd_startswith = 1
},
#ifdef CONFIG_USER_ONLY
/*
* Host I/O Packets. See [1] for details.
* [1] https://sourceware.org/gdb/onlinedocs/gdb/Host-I_002fO-Packets.html
*/
{
.handler = gdb_handle_v_file_open,
.cmd = "File:open:",
.cmd_startswith = 1,
.schema = "s,L,L0"
},
{
.handler = gdb_handle_v_file_close,
.cmd = "File:close:",
.cmd_startswith = 1,
.schema = "l0"
},
{
.handler = gdb_handle_v_file_pread,
.cmd = "File:pread:",
.cmd_startswith = 1,
.schema = "l,L,L0"
},
{
.handler = gdb_handle_v_file_readlink,
.cmd = "File:readlink:",
.cmd_startswith = 1,
.schema = "s0"
},
#endif
};
static void handle_v_commands(GArray *params, void *user_ctx)
{
if (!params->len) {
return;
}
if (process_string_cmd(get_param(params, 0)->data,
gdb_v_commands_table,
ARRAY_SIZE(gdb_v_commands_table))) {
gdb_put_packet("");
}
}
static void handle_query_qemu_sstepbits(GArray *params, void *user_ctx)
{
g_string_printf(gdbserver_state.str_buf, "ENABLE=%x", SSTEP_ENABLE);
if (gdbserver_state.supported_sstep_flags & SSTEP_NOIRQ) {
g_string_append_printf(gdbserver_state.str_buf, ",NOIRQ=%x",
SSTEP_NOIRQ);
}
if (gdbserver_state.supported_sstep_flags & SSTEP_NOTIMER) {
g_string_append_printf(gdbserver_state.str_buf, ",NOTIMER=%x",
SSTEP_NOTIMER);
}
gdb_put_strbuf();
}
static void handle_set_qemu_sstep(GArray *params, void *user_ctx)
{
int new_sstep_flags;
if (!params->len) {
return;
}
new_sstep_flags = get_param(params, 0)->val_ul;
if (new_sstep_flags & ~gdbserver_state.supported_sstep_flags) {
gdb_put_packet("E22");
return;
}
gdbserver_state.sstep_flags = new_sstep_flags;
gdb_put_packet("OK");
}
static void handle_query_qemu_sstep(GArray *params, void *user_ctx)
{
g_string_printf(gdbserver_state.str_buf, "0x%x",
gdbserver_state.sstep_flags);
gdb_put_strbuf();
}
static void handle_query_curr_tid(GArray *params, void *user_ctx)
{
CPUState *cpu;
GDBProcess *process;
/*
* "Current thread" remains vague in the spec, so always return
* the first thread of the current process (gdb returns the
* first thread).
*/
process = gdb_get_cpu_process(gdbserver_state.g_cpu);
cpu = gdb_get_first_cpu_in_process(process);
g_string_assign(gdbserver_state.str_buf, "QC");
gdb_append_thread_id(cpu, gdbserver_state.str_buf);
gdb_put_strbuf();
}
static void handle_query_threads(GArray *params, void *user_ctx)
{
if (!gdbserver_state.query_cpu) {
gdb_put_packet("l");
return;
}
g_string_assign(gdbserver_state.str_buf, "m");
gdb_append_thread_id(gdbserver_state.query_cpu, gdbserver_state.str_buf);
gdb_put_strbuf();
gdbserver_state.query_cpu = gdb_next_attached_cpu(gdbserver_state.query_cpu);
}
static void handle_query_first_threads(GArray *params, void *user_ctx)
{
gdbserver_state.query_cpu = gdb_first_attached_cpu();
handle_query_threads(params, user_ctx);
}
static void handle_query_thread_extra(GArray *params, void *user_ctx)
{
g_autoptr(GString) rs = g_string_new(NULL);
CPUState *cpu;
if (!params->len ||
get_param(params, 0)->thread_id.kind == GDB_READ_THREAD_ERR) {
gdb_put_packet("E22");
return;
}
cpu = gdb_get_cpu(get_param(params, 0)->thread_id.pid,
get_param(params, 0)->thread_id.tid);
if (!cpu) {
return;
}
cpu_synchronize_state(cpu);
if (gdbserver_state.multiprocess && (gdbserver_state.process_num > 1)) {
/* Print the CPU model and name in multiprocess mode */
ObjectClass *oc = object_get_class(OBJECT(cpu));
const char *cpu_model = object_class_get_name(oc);
const char *cpu_name =
object_get_canonical_path_component(OBJECT(cpu));
g_string_printf(rs, "%s %s [%s]", cpu_model, cpu_name,
cpu->halted ? "halted " : "running");
} else {
g_string_printf(rs, "CPU#%d [%s]", cpu->cpu_index,
cpu->halted ? "halted " : "running");
}
trace_gdbstub_op_extra_info(rs->str);
gdb_memtohex(gdbserver_state.str_buf, (uint8_t *)rs->str, rs->len);
gdb_put_strbuf();
}
static void handle_query_supported(GArray *params, void *user_ctx)
{
CPUClass *cc;
g_string_printf(gdbserver_state.str_buf, "PacketSize=%x", MAX_PACKET_LENGTH);
cc = CPU_GET_CLASS(first_cpu);
if (cc->gdb_core_xml_file) {
g_string_append(gdbserver_state.str_buf, ";qXfer:features:read+");
}
if (gdb_can_reverse()) {
g_string_append(gdbserver_state.str_buf,
";ReverseStep+;ReverseContinue+");
}
#if defined(CONFIG_USER_ONLY)
#if defined(CONFIG_LINUX)
if (get_task_state(gdbserver_state.c_cpu)) {
g_string_append(gdbserver_state.str_buf, ";qXfer:auxv:read+");
}
g_string_append(gdbserver_state.str_buf, ";QCatchSyscalls+");
g_string_append(gdbserver_state.str_buf, ";qXfer:siginfo:read+");
#endif
g_string_append(gdbserver_state.str_buf, ";qXfer:exec-file:read+");
#endif
if (params->len) {
const char *gdb_supported = get_param(params, 0)->data;
if (strstr(gdb_supported, "multiprocess+")) {
gdbserver_state.multiprocess = true;
}
#if defined(CONFIG_USER_ONLY)
gdb_handle_query_supported_user(gdb_supported);
#endif
}
g_string_append(gdbserver_state.str_buf, ";vContSupported+;multiprocess+");
gdb_put_strbuf();
}
static void handle_query_xfer_features(GArray *params, void *user_ctx)
{
GDBProcess *process;
CPUClass *cc;
unsigned long len, total_len, addr;
const char *xml;
const char *p;
if (params->len < 3) {
gdb_put_packet("E22");
return;
}
process = gdb_get_cpu_process(gdbserver_state.g_cpu);
cc = CPU_GET_CLASS(gdbserver_state.g_cpu);
if (!cc->gdb_core_xml_file) {
gdb_put_packet("");
return;
}
p = get_param(params, 0)->data;
xml = get_feature_xml(p, &p, process);
if (!xml) {
gdb_put_packet("E00");
return;
}
addr = get_param(params, 1)->val_ul;
len = get_param(params, 2)->val_ul;
total_len = strlen(xml);
if (addr > total_len) {
gdb_put_packet("E00");
return;
}
if (len > (MAX_PACKET_LENGTH - 5) / 2) {
len = (MAX_PACKET_LENGTH - 5) / 2;
}
if (len < total_len - addr) {
g_string_assign(gdbserver_state.str_buf, "m");
gdb_memtox(gdbserver_state.str_buf, xml + addr, len);
} else {
g_string_assign(gdbserver_state.str_buf, "l");
gdb_memtox(gdbserver_state.str_buf, xml + addr, total_len - addr);
}
gdb_put_packet_binary(gdbserver_state.str_buf->str,
gdbserver_state.str_buf->len, true);
}
static void handle_query_qemu_supported(GArray *params, void *user_ctx)
{
g_string_printf(gdbserver_state.str_buf, "sstepbits;sstep");
#ifndef CONFIG_USER_ONLY
g_string_append(gdbserver_state.str_buf, ";PhyMemMode");
#endif
gdb_put_strbuf();
}
static const GdbCmdParseEntry gdb_gen_query_set_common_table[] = {
/* Order is important if has same prefix */
{
.handler = handle_query_qemu_sstepbits,
.cmd = "qemu.sstepbits",
},
{
.handler = handle_query_qemu_sstep,
.cmd = "qemu.sstep",
},
{
.handler = handle_set_qemu_sstep,
.cmd = "qemu.sstep=",
.cmd_startswith = 1,
.schema = "l0"
},
};
static const GdbCmdParseEntry gdb_gen_query_table[] = {
{
.handler = handle_query_curr_tid,
.cmd = "C",
},
{
.handler = handle_query_threads,
.cmd = "sThreadInfo",
},
{
.handler = handle_query_first_threads,
.cmd = "fThreadInfo",
},
{
.handler = handle_query_thread_extra,
.cmd = "ThreadExtraInfo,",
.cmd_startswith = 1,
.schema = "t0"
},
#ifdef CONFIG_USER_ONLY
{
.handler = gdb_handle_query_offsets,
.cmd = "Offsets",
},
#else
{
.handler = gdb_handle_query_rcmd,
.cmd = "Rcmd,",
.cmd_startswith = 1,
.schema = "s0"
},
#endif
{
.handler = handle_query_supported,
.cmd = "Supported:",
.cmd_startswith = 1,
.schema = "s0"
},
{
.handler = handle_query_supported,
.cmd = "Supported",
.schema = "s0"
},
{
.handler = handle_query_xfer_features,
.cmd = "Xfer:features:read:",
.cmd_startswith = 1,
.schema = "s:l,l0"
},
#if defined(CONFIG_USER_ONLY)
#if defined(CONFIG_LINUX)
{
.handler = gdb_handle_query_xfer_auxv,
.cmd = "Xfer:auxv:read::",
.cmd_startswith = 1,
.schema = "l,l0"
},
{
.handler = gdb_handle_query_xfer_siginfo,
.cmd = "Xfer:siginfo:read::",
.cmd_startswith = 1,
.schema = "l,l0"
},
#endif
{
.handler = gdb_handle_query_xfer_exec_file,
.cmd = "Xfer:exec-file:read:",
.cmd_startswith = 1,
.schema = "l:l,l0"
},
#endif
{
.handler = gdb_handle_query_attached,
.cmd = "Attached:",
.cmd_startswith = 1
},
{
.handler = gdb_handle_query_attached,
.cmd = "Attached",
},
{
.handler = handle_query_qemu_supported,
.cmd = "qemu.Supported",
},
#ifndef CONFIG_USER_ONLY
{
.handler = gdb_handle_query_qemu_phy_mem_mode,
.cmd = "qemu.PhyMemMode",
},
#endif
};
static const GdbCmdParseEntry gdb_gen_set_table[] = {
/* Order is important if has same prefix */
{
.handler = handle_set_qemu_sstep,
.cmd = "qemu.sstep:",
.cmd_startswith = 1,
.schema = "l0"
},
#ifndef CONFIG_USER_ONLY
{
.handler = gdb_handle_set_qemu_phy_mem_mode,
.cmd = "qemu.PhyMemMode:",
.cmd_startswith = 1,
.schema = "l0"
},
#endif
#if defined(CONFIG_USER_ONLY)
{
.handler = gdb_handle_set_catch_syscalls,
.cmd = "CatchSyscalls:",
.cmd_startswith = 1,
.schema = "s0",
},
#endif
};
static void handle_gen_query(GArray *params, void *user_ctx)
{
if (!params->len) {
return;
}
if (!process_string_cmd(get_param(params, 0)->data,
gdb_gen_query_set_common_table,
ARRAY_SIZE(gdb_gen_query_set_common_table))) {
return;
}
if (process_string_cmd(get_param(params, 0)->data,
gdb_gen_query_table,
ARRAY_SIZE(gdb_gen_query_table))) {
gdb_put_packet("");
}
}
static void handle_gen_set(GArray *params, void *user_ctx)
{
if (!params->len) {
return;
}
if (!process_string_cmd(get_param(params, 0)->data,
gdb_gen_query_set_common_table,
ARRAY_SIZE(gdb_gen_query_set_common_table))) {
return;
}
if (process_string_cmd(get_param(params, 0)->data,
gdb_gen_set_table,
ARRAY_SIZE(gdb_gen_set_table))) {
gdb_put_packet("");
}
}
static void handle_target_halt(GArray *params, void *user_ctx)
{
if (gdbserver_state.allow_stop_reply) {
g_string_printf(gdbserver_state.str_buf, "T%02xthread:", GDB_SIGNAL_TRAP);
gdb_append_thread_id(gdbserver_state.c_cpu, gdbserver_state.str_buf);
g_string_append_c(gdbserver_state.str_buf, ';');
gdb_put_strbuf();
gdbserver_state.allow_stop_reply = false;
}
/*
* Remove all the breakpoints when this query is issued,
* because gdb is doing an initial connect and the state
* should be cleaned up.
*/
gdb_breakpoint_remove_all(gdbserver_state.c_cpu);
}
static int gdb_handle_packet(const char *line_buf)
{
const GdbCmdParseEntry *cmd_parser = NULL;
trace_gdbstub_io_command(line_buf);
switch (line_buf[0]) {
case '!':
gdb_put_packet("OK");
break;
case '?':
{
static const GdbCmdParseEntry target_halted_cmd_desc = {
.handler = handle_target_halt,
.cmd = "?",
.cmd_startswith = 1,
.allow_stop_reply = true,
};
cmd_parser = &target_halted_cmd_desc;
}
break;
case 'c':
{
static const GdbCmdParseEntry continue_cmd_desc = {
.handler = handle_continue,
.cmd = "c",
.cmd_startswith = 1,
.allow_stop_reply = true,
.schema = "L0"
};
cmd_parser = &continue_cmd_desc;
}
break;
case 'C':
{
static const GdbCmdParseEntry cont_with_sig_cmd_desc = {
.handler = handle_cont_with_sig,
.cmd = "C",
.cmd_startswith = 1,
.allow_stop_reply = true,
.schema = "l0"
};
cmd_parser = &cont_with_sig_cmd_desc;
}
break;
case 'v':
{
static const GdbCmdParseEntry v_cmd_desc = {
.handler = handle_v_commands,
.cmd = "v",
.cmd_startswith = 1,
.schema = "s0"
};
cmd_parser = &v_cmd_desc;
}
break;
case 'k':
/* Kill the target */
error_report("QEMU: Terminated via GDBstub");
gdb_exit(0);
gdb_qemu_exit(0);
break;
case 'D':
{
static const GdbCmdParseEntry detach_cmd_desc = {
.handler = handle_detach,
.cmd = "D",
.cmd_startswith = 1,
.schema = "?.l0"
};
cmd_parser = &detach_cmd_desc;
}
break;
case 's':
{
static const GdbCmdParseEntry step_cmd_desc = {
.handler = handle_step,
.cmd = "s",
.cmd_startswith = 1,
.allow_stop_reply = true,
.schema = "L0"
};
cmd_parser = &step_cmd_desc;
}
break;
case 'b':
{
static const GdbCmdParseEntry backward_cmd_desc = {
.handler = handle_backward,
.cmd = "b",
.cmd_startswith = 1,
.allow_stop_reply = true,
.schema = "o0"
};
cmd_parser = &backward_cmd_desc;
}
break;
case 'F':
{
static const GdbCmdParseEntry file_io_cmd_desc = {
.handler = gdb_handle_file_io,
.cmd = "F",
.cmd_startswith = 1,
.schema = "L,L,o0"
};
cmd_parser = &file_io_cmd_desc;
}
break;
case 'g':
{
static const GdbCmdParseEntry read_all_regs_cmd_desc = {
.handler = handle_read_all_regs,
.cmd = "g",
.cmd_startswith = 1
};
cmd_parser = &read_all_regs_cmd_desc;
}
break;
case 'G':
{
static const GdbCmdParseEntry write_all_regs_cmd_desc = {
.handler = handle_write_all_regs,
.cmd = "G",
.cmd_startswith = 1,
.schema = "s0"
};
cmd_parser = &write_all_regs_cmd_desc;
}
break;
case 'm':
{
static const GdbCmdParseEntry read_mem_cmd_desc = {
.handler = handle_read_mem,
.cmd = "m",
.cmd_startswith = 1,
.schema = "L,L0"
};
cmd_parser = &read_mem_cmd_desc;
}
break;
case 'M':
{
static const GdbCmdParseEntry write_mem_cmd_desc = {
.handler = handle_write_mem,
.cmd = "M",
.cmd_startswith = 1,
.schema = "L,L:s0"
};
cmd_parser = &write_mem_cmd_desc;
}
break;
case 'p':
{
static const GdbCmdParseEntry get_reg_cmd_desc = {
.handler = handle_get_reg,
.cmd = "p",
.cmd_startswith = 1,
.schema = "L0"
};
cmd_parser = &get_reg_cmd_desc;
}
break;
case 'P':
{
static const GdbCmdParseEntry set_reg_cmd_desc = {
.handler = handle_set_reg,
.cmd = "P",
.cmd_startswith = 1,
.schema = "L?s0"
};
cmd_parser = &set_reg_cmd_desc;
}
break;
case 'Z':
{
static const GdbCmdParseEntry insert_bp_cmd_desc = {
.handler = handle_insert_bp,
.cmd = "Z",
.cmd_startswith = 1,
.schema = "l?L?L0"
};
cmd_parser = &insert_bp_cmd_desc;
}
break;
case 'z':
{
static const GdbCmdParseEntry remove_bp_cmd_desc = {
.handler = handle_remove_bp,
.cmd = "z",
.cmd_startswith = 1,
.schema = "l?L?L0"
};
cmd_parser = &remove_bp_cmd_desc;
}
break;
case 'H':
{
static const GdbCmdParseEntry set_thread_cmd_desc = {
.handler = handle_set_thread,
.cmd = "H",
.cmd_startswith = 1,
.schema = "o.t0"
};
cmd_parser = &set_thread_cmd_desc;
}
break;
case 'T':
{
static const GdbCmdParseEntry thread_alive_cmd_desc = {
.handler = handle_thread_alive,
.cmd = "T",
.cmd_startswith = 1,
.schema = "t0"
};
cmd_parser = &thread_alive_cmd_desc;
}
break;
case 'q':
{
static const GdbCmdParseEntry gen_query_cmd_desc = {
.handler = handle_gen_query,
.cmd = "q",
.cmd_startswith = 1,
.schema = "s0"
};
cmd_parser = &gen_query_cmd_desc;
}
break;
case 'Q':
{
static const GdbCmdParseEntry gen_set_cmd_desc = {
.handler = handle_gen_set,
.cmd = "Q",
.cmd_startswith = 1,
.schema = "s0"
};
cmd_parser = &gen_set_cmd_desc;
}
break;
default:
/* put empty packet */
gdb_put_packet("");
break;
}
if (cmd_parser) {
run_cmd_parser(line_buf, cmd_parser);
}
return RS_IDLE;
}
void gdb_set_stop_cpu(CPUState *cpu)
{
GDBProcess *p = gdb_get_cpu_process(cpu);
if (!p->attached) {
/*
* Having a stop CPU corresponding to a process that is not attached
* confuses GDB. So we ignore the request.
*/
return;
}
gdbserver_state.c_cpu = cpu;
gdbserver_state.g_cpu = cpu;
}
void gdb_read_byte(uint8_t ch)
{
uint8_t reply;
gdbserver_state.allow_stop_reply = false;
#ifndef CONFIG_USER_ONLY
if (gdbserver_state.last_packet->len) {
/* Waiting for a response to the last packet. If we see the start
of a new command then abandon the previous response. */
if (ch == '-') {
trace_gdbstub_err_got_nack();
gdb_put_buffer(gdbserver_state.last_packet->data,
gdbserver_state.last_packet->len);
} else if (ch == '+') {
trace_gdbstub_io_got_ack();
} else {
trace_gdbstub_io_got_unexpected(ch);
}
if (ch == '+' || ch == '$') {
g_byte_array_set_size(gdbserver_state.last_packet, 0);
}
if (ch != '$')
return;
}
if (runstate_is_running()) {
/*
* When the CPU is running, we cannot do anything except stop
* it when receiving a char. This is expected on a Ctrl-C in the
* gdb client. Because we are in all-stop mode, gdb sends a
* 0x03 byte which is not a usual packet, so we handle it specially
* here, but it does expect a stop reply.
*/
if (ch != 0x03) {
trace_gdbstub_err_unexpected_runpkt(ch);
} else {
gdbserver_state.allow_stop_reply = true;
}
vm_stop(RUN_STATE_PAUSED);
} else
#endif
{
switch(gdbserver_state.state) {
case RS_IDLE:
if (ch == '$') {
/* start of command packet */
gdbserver_state.line_buf_index = 0;
gdbserver_state.line_sum = 0;
gdbserver_state.state = RS_GETLINE;
} else if (ch == '+') {
/*
* do nothing, gdb may preemptively send out ACKs on
* initial connection
*/
} else {
trace_gdbstub_err_garbage(ch);
}
break;
case RS_GETLINE:
if (ch == '}') {
/* start escape sequence */
gdbserver_state.state = RS_GETLINE_ESC;
gdbserver_state.line_sum += ch;
} else if (ch == '*') {
/* start run length encoding sequence */
gdbserver_state.state = RS_GETLINE_RLE;
gdbserver_state.line_sum += ch;
} else if (ch == '#') {
/* end of command, start of checksum*/
gdbserver_state.state = RS_CHKSUM1;
} else if (gdbserver_state.line_buf_index >= sizeof(gdbserver_state.line_buf) - 1) {
trace_gdbstub_err_overrun();
gdbserver_state.state = RS_IDLE;
} else {
/* unescaped command character */
gdbserver_state.line_buf[gdbserver_state.line_buf_index++] = ch;
gdbserver_state.line_sum += ch;
}
break;
case RS_GETLINE_ESC:
if (ch == '#') {
/* unexpected end of command in escape sequence */
gdbserver_state.state = RS_CHKSUM1;
} else if (gdbserver_state.line_buf_index >= sizeof(gdbserver_state.line_buf) - 1) {
/* command buffer overrun */
trace_gdbstub_err_overrun();
gdbserver_state.state = RS_IDLE;
} else {
/* parse escaped character and leave escape state */
gdbserver_state.line_buf[gdbserver_state.line_buf_index++] = ch ^ 0x20;
gdbserver_state.line_sum += ch;
gdbserver_state.state = RS_GETLINE;
}
break;
case RS_GETLINE_RLE:
/*
* Run-length encoding is explained in "Debugging with GDB /
* Appendix E GDB Remote Serial Protocol / Overview".
*/
if (ch < ' ' || ch == '#' || ch == '$' || ch > 126) {
/* invalid RLE count encoding */
trace_gdbstub_err_invalid_repeat(ch);
gdbserver_state.state = RS_GETLINE;
} else {
/* decode repeat length */
int repeat = ch - ' ' + 3;
if (gdbserver_state.line_buf_index + repeat >= sizeof(gdbserver_state.line_buf) - 1) {
/* that many repeats would overrun the command buffer */
trace_gdbstub_err_overrun();
gdbserver_state.state = RS_IDLE;
} else if (gdbserver_state.line_buf_index < 1) {
/* got a repeat but we have nothing to repeat */
trace_gdbstub_err_invalid_rle();
gdbserver_state.state = RS_GETLINE;
} else {
/* repeat the last character */
memset(gdbserver_state.line_buf + gdbserver_state.line_buf_index,
gdbserver_state.line_buf[gdbserver_state.line_buf_index - 1], repeat);
gdbserver_state.line_buf_index += repeat;
gdbserver_state.line_sum += ch;
gdbserver_state.state = RS_GETLINE;
}
}
break;
case RS_CHKSUM1:
/* get high hex digit of checksum */
if (!isxdigit(ch)) {
trace_gdbstub_err_checksum_invalid(ch);
gdbserver_state.state = RS_GETLINE;
break;
}
gdbserver_state.line_buf[gdbserver_state.line_buf_index] = '\0';
gdbserver_state.line_csum = fromhex(ch) << 4;
gdbserver_state.state = RS_CHKSUM2;
break;
case RS_CHKSUM2:
/* get low hex digit of checksum */
if (!isxdigit(ch)) {
trace_gdbstub_err_checksum_invalid(ch);
gdbserver_state.state = RS_GETLINE;
break;
}
gdbserver_state.line_csum |= fromhex(ch);
if (gdbserver_state.line_csum != (gdbserver_state.line_sum & 0xff)) {
trace_gdbstub_err_checksum_incorrect(gdbserver_state.line_sum, gdbserver_state.line_csum);
/* send NAK reply */
reply = '-';
gdb_put_buffer(&reply, 1);
gdbserver_state.state = RS_IDLE;
} else {
/* send ACK reply */
reply = '+';
gdb_put_buffer(&reply, 1);
gdbserver_state.state = gdb_handle_packet(gdbserver_state.line_buf);
}
break;
default:
abort();
}
}
}
/*
* Create the process that will contain all the "orphan" CPUs (that are not
* part of a CPU cluster). Note that if this process contains no CPUs, it won't
* be attachable and thus will be invisible to the user.
*/
void gdb_create_default_process(GDBState *s)
{
GDBProcess *process;
int pid;
#ifdef CONFIG_USER_ONLY
assert(gdbserver_state.process_num == 0);
pid = getpid();
#else
if (gdbserver_state.process_num) {
pid = s->processes[s->process_num - 1].pid;
} else {
pid = 0;
}
/* We need an available PID slot for this process */
assert(pid < UINT32_MAX);
pid++;
#endif
s->processes = g_renew(GDBProcess, s->processes, ++s->process_num);
process = &s->processes[s->process_num - 1];
process->pid = pid;
process->attached = false;
process->target_xml = NULL;
}