gdbstub: Implement generic set/query (Q/q pkt) with new infra

The generic set/query packets contains implementation for varioius
sub-commands which are required for GDB and also additional commands
which are QEMU specific.

To see which QEMU specific commands are available use the command
gdb> maintenance packet qqemu.Supported

Currently the only implemented QEMU specific command is the command
that sets the single step behavior.

gdb> maintenance packet qqemu.sstepbits
Will display the MASK bits used to control the single stepping.

gdb> maintenance packet qqemu.sstep
Will display the current value of the mask used when single stepping.

gdb> maintenance packet Qqemu.sstep:HEX_VALUE
Will change the single step mask.

Signed-off-by: Jon Doron <arilou@gmail.com>
Message-Id: <20190529064148.19856-18-arilou@gmail.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
This commit is contained in:
Jon Doron 2019-05-29 09:41:45 +03:00 committed by Alex Bennée
parent 8536ec02fe
commit 2704efad51

557
gdbstub.c
View File

@ -1134,14 +1134,6 @@ static GDBThreadIdKind read_thread_id(const char *buf, const char **end_buf,
return GDB_ONE_THREAD;
}
static int is_query_packet(const char *p, const char *query, char separator)
{
unsigned int query_len = strlen(query);
return strncmp(p, query, query_len) == 0 &&
(p[query_len] == '\0' || p[query_len] == separator);
}
/**
* gdb_handle_vcont - Parses and handles a vCont packet.
* returns -ENOTSUP if a command is unsupported, -EINVAL or -ERANGE if there is
@ -1922,18 +1914,368 @@ static void handle_v_commands(GdbCmdContext *gdb_ctx, void *user_ctx)
}
}
static int gdb_handle_packet(GDBState *s, const char *line_buf)
static void handle_query_qemu_sstepbits(GdbCmdContext *gdb_ctx, void *user_ctx)
{
snprintf(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf),
"ENABLE=%x,NOIRQ=%x,NOTIMER=%x", SSTEP_ENABLE,
SSTEP_NOIRQ, SSTEP_NOTIMER);
put_packet(gdb_ctx->s, gdb_ctx->str_buf);
}
static void handle_set_qemu_sstep(GdbCmdContext *gdb_ctx, void *user_ctx)
{
if (!gdb_ctx->num_params) {
return;
}
sstep_flags = gdb_ctx->params[0].val_ul;
put_packet(gdb_ctx->s, "OK");
}
static void handle_query_qemu_sstep(GdbCmdContext *gdb_ctx, void *user_ctx)
{
snprintf(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf), "0x%x", sstep_flags);
put_packet(gdb_ctx->s, gdb_ctx->str_buf);
}
static void handle_query_curr_tid(GdbCmdContext *gdb_ctx, void *user_ctx)
{
CPUState *cpu;
GDBProcess *process;
char thread_id[16];
/*
* "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(gdb_ctx->s, gdb_ctx->s->g_cpu);
cpu = get_first_cpu_in_process(gdb_ctx->s, process);
gdb_fmt_thread_id(gdb_ctx->s, cpu, thread_id, sizeof(thread_id));
snprintf(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf), "QC%s", thread_id);
put_packet(gdb_ctx->s, gdb_ctx->str_buf);
}
static void handle_query_threads(GdbCmdContext *gdb_ctx, void *user_ctx)
{
char thread_id[16];
if (!gdb_ctx->s->query_cpu) {
put_packet(gdb_ctx->s, "l");
return;
}
gdb_fmt_thread_id(gdb_ctx->s, gdb_ctx->s->query_cpu, thread_id,
sizeof(thread_id));
snprintf(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf), "m%s", thread_id);
put_packet(gdb_ctx->s, gdb_ctx->str_buf);
gdb_ctx->s->query_cpu =
gdb_next_attached_cpu(gdb_ctx->s, gdb_ctx->s->query_cpu);
}
static void handle_query_first_threads(GdbCmdContext *gdb_ctx, void *user_ctx)
{
gdb_ctx->s->query_cpu = gdb_first_attached_cpu(gdb_ctx->s);
handle_query_threads(gdb_ctx, user_ctx);
}
static void handle_query_thread_extra(GdbCmdContext *gdb_ctx, void *user_ctx)
{
CPUState *cpu;
int len;
if (!gdb_ctx->num_params ||
gdb_ctx->params[0].thread_id.kind == GDB_READ_THREAD_ERR) {
put_packet(gdb_ctx->s, "E22");
return;
}
cpu = gdb_get_cpu(gdb_ctx->s, gdb_ctx->params[0].thread_id.pid,
gdb_ctx->params[0].thread_id.tid);
if (!cpu) {
return;
}
cpu_synchronize_state(cpu);
if (gdb_ctx->s->multiprocess && (gdb_ctx->s->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);
char *cpu_name = object_get_canonical_path_component(OBJECT(cpu));
len = snprintf((char *)gdb_ctx->mem_buf, sizeof(gdb_ctx->str_buf) / 2,
"%s %s [%s]", cpu_model, cpu_name,
cpu->halted ? "halted " : "running");
g_free(cpu_name);
} else {
/* memtohex() doubles the required space */
len = snprintf((char *)gdb_ctx->mem_buf, sizeof(gdb_ctx->str_buf) / 2,
"CPU#%d [%s]", cpu->cpu_index,
cpu->halted ? "halted " : "running");
}
trace_gdbstub_op_extra_info((char *)gdb_ctx->mem_buf);
memtohex(gdb_ctx->str_buf, gdb_ctx->mem_buf, len);
put_packet(gdb_ctx->s, gdb_ctx->str_buf);
}
#ifdef CONFIG_USER_ONLY
static void handle_query_offsets(GdbCmdContext *gdb_ctx, void *user_ctx)
{
TaskState *ts;
ts = gdb_ctx->s->c_cpu->opaque;
snprintf(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf),
"Text=" TARGET_ABI_FMT_lx ";Data=" TARGET_ABI_FMT_lx
";Bss=" TARGET_ABI_FMT_lx,
ts->info->code_offset,
ts->info->data_offset,
ts->info->data_offset);
put_packet(gdb_ctx->s, gdb_ctx->str_buf);
}
#else
static void handle_query_rcmd(GdbCmdContext *gdb_ctx, void *user_ctx)
{
int len;
if (!gdb_ctx->num_params) {
put_packet(gdb_ctx->s, "E22");
return;
}
len = strlen(gdb_ctx->params[0].data);
if (len % 2) {
put_packet(gdb_ctx->s, "E01");
return;
}
len = len / 2;
hextomem(gdb_ctx->mem_buf, gdb_ctx->params[0].data, len);
gdb_ctx->mem_buf[len++] = 0;
qemu_chr_be_write(gdb_ctx->s->mon_chr, gdb_ctx->mem_buf, len);
put_packet(gdb_ctx->s, "OK");
}
#endif
static void handle_query_supported(GdbCmdContext *gdb_ctx, void *user_ctx)
{
CPUClass *cc;
snprintf(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf), "PacketSize=%x",
MAX_PACKET_LENGTH);
cc = CPU_GET_CLASS(first_cpu);
if (cc->gdb_core_xml_file) {
pstrcat(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf),
";qXfer:features:read+");
}
if (gdb_ctx->num_params &&
strstr(gdb_ctx->params[0].data, "multiprocess+")) {
gdb_ctx->s->multiprocess = true;
}
pstrcat(gdb_ctx->str_buf, sizeof(gdb_ctx->str_buf), ";multiprocess+");
put_packet(gdb_ctx->s, gdb_ctx->str_buf);
}
static void handle_query_xfer_features(GdbCmdContext *gdb_ctx, void *user_ctx)
{
GDBProcess *process;
CPUClass *cc;
unsigned long len, total_len, addr;
const char *xml;
const char *p;
uint32_t pid, tid;
int ch, type;
if (gdb_ctx->num_params < 3) {
put_packet(gdb_ctx->s, "E22");
return;
}
process = gdb_get_cpu_process(gdb_ctx->s, gdb_ctx->s->g_cpu);
cc = CPU_GET_CLASS(gdb_ctx->s->g_cpu);
if (!cc->gdb_core_xml_file) {
put_packet(gdb_ctx->s, "");
return;
}
gdb_has_xml = true;
p = gdb_ctx->params[0].data;
xml = get_feature_xml(gdb_ctx->s, p, &p, process);
if (!xml) {
put_packet(gdb_ctx->s, "E00");
return;
}
addr = gdb_ctx->params[1].val_ul;
len = gdb_ctx->params[2].val_ul;
total_len = strlen(xml);
if (addr > total_len) {
put_packet(gdb_ctx->s, "E00");
return;
}
if (len > (MAX_PACKET_LENGTH - 5) / 2) {
len = (MAX_PACKET_LENGTH - 5) / 2;
}
if (len < total_len - addr) {
gdb_ctx->str_buf[0] = 'm';
len = memtox(gdb_ctx->str_buf + 1, xml + addr, len);
} else {
gdb_ctx->str_buf[0] = 'l';
len = memtox(gdb_ctx->str_buf + 1, xml + addr, total_len - addr);
}
put_packet_binary(gdb_ctx->s, gdb_ctx->str_buf, len + 1, true);
}
static void handle_query_attached(GdbCmdContext *gdb_ctx, void *user_ctx)
{
put_packet(gdb_ctx->s, GDB_ATTACHED);
}
static void handle_query_qemu_supported(GdbCmdContext *gdb_ctx, void *user_ctx)
{
put_packet(gdb_ctx->s, "sstepbits;sstep");
}
static 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 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 = handle_query_offsets,
.cmd = "Offsets",
},
#else
{
.handler = 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"
},
{
.handler = handle_query_attached,
.cmd = "Attached:",
.cmd_startswith = 1
},
{
.handler = handle_query_attached,
.cmd = "Attached",
},
{
.handler = handle_query_qemu_supported,
.cmd = "qemu.Supported",
},
};
static 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"
},
};
static void handle_gen_query(GdbCmdContext *gdb_ctx, void *user_ctx)
{
if (!gdb_ctx->num_params) {
return;
}
if (!process_string_cmd(gdb_ctx->s, NULL, gdb_ctx->params[0].data,
gdb_gen_query_set_common_table,
ARRAY_SIZE(gdb_gen_query_set_common_table))) {
return;
}
if (process_string_cmd(gdb_ctx->s, NULL, gdb_ctx->params[0].data,
gdb_gen_query_table,
ARRAY_SIZE(gdb_gen_query_table))) {
put_packet(gdb_ctx->s, "");
}
}
static void handle_gen_set(GdbCmdContext *gdb_ctx, void *user_ctx)
{
if (!gdb_ctx->num_params) {
return;
}
if (!process_string_cmd(gdb_ctx->s, NULL, gdb_ctx->params[0].data,
gdb_gen_query_set_common_table,
ARRAY_SIZE(gdb_gen_query_set_common_table))) {
return;
}
if (process_string_cmd(gdb_ctx->s, NULL, gdb_ctx->params[0].data,
gdb_gen_set_table,
ARRAY_SIZE(gdb_gen_set_table))) {
put_packet(gdb_ctx->s, "");
}
}
static int gdb_handle_packet(GDBState *s, const char *line_buf)
{
const char *p;
int ch;
uint8_t mem_buf[MAX_PACKET_LENGTH];
char buf[sizeof(mem_buf) + 1 /* trailing NUL */];
char thread_id[16];
target_ulong addr, len;
const GdbCmdParseEntry *cmd_parser = NULL;
trace_gdbstub_io_command(line_buf);
@ -2135,183 +2477,28 @@ static int gdb_handle_packet(GDBState *s, const char *line_buf)
}
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':
/* parse any 'q' packets here */
if (!strcmp(p,"qemu.sstepbits")) {
/* Query Breakpoint bit definitions */
snprintf(buf, sizeof(buf), "ENABLE=%x,NOIRQ=%x,NOTIMER=%x",
SSTEP_ENABLE,
SSTEP_NOIRQ,
SSTEP_NOTIMER);
put_packet(s, buf);
break;
} else if (is_query_packet(p, "qemu.sstep", '=')) {
/* Display or change the sstep_flags */
p += 10;
if (*p != '=') {
/* Display current setting */
snprintf(buf, sizeof(buf), "0x%x", sstep_flags);
put_packet(s, buf);
break;
}
p++;
type = strtoul(p, (char **)&p, 16);
sstep_flags = type;
put_packet(s, "OK");
break;
} else if (strcmp(p,"C") == 0) {
/*
* "Current thread" remains vague in the spec, so always return
* the first thread of the current process (gdb returns the
* first thread).
*/
cpu = get_first_cpu_in_process(s, gdb_get_cpu_process(s, s->g_cpu));
snprintf(buf, sizeof(buf), "QC%s",
gdb_fmt_thread_id(s, cpu, thread_id, sizeof(thread_id)));
put_packet(s, buf);
break;
} else if (strcmp(p,"fThreadInfo") == 0) {
s->query_cpu = gdb_first_attached_cpu(s);
goto report_cpuinfo;
} else if (strcmp(p,"sThreadInfo") == 0) {
report_cpuinfo:
if (s->query_cpu) {
snprintf(buf, sizeof(buf), "m%s",
gdb_fmt_thread_id(s, s->query_cpu,
thread_id, sizeof(thread_id)));
put_packet(s, buf);
s->query_cpu = gdb_next_attached_cpu(s, s->query_cpu);
} else
put_packet(s, "l");
break;
} else if (strncmp(p,"ThreadExtraInfo,", 16) == 0) {
if (read_thread_id(p + 16, &p, &pid, &tid) == GDB_READ_THREAD_ERR) {
put_packet(s, "E22");
break;
}
cpu = gdb_get_cpu(s, pid, tid);
if (cpu != NULL) {
cpu_synchronize_state(cpu);
if (s->multiprocess && (s->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);
char *cpu_name =
object_get_canonical_path_component(OBJECT(cpu));
len = snprintf((char *)mem_buf, sizeof(buf) / 2,
"%s %s [%s]", cpu_model, cpu_name,
cpu->halted ? "halted " : "running");
g_free(cpu_name);
} else {
/* memtohex() doubles the required space */
len = snprintf((char *)mem_buf, sizeof(buf) / 2,
"CPU#%d [%s]", cpu->cpu_index,
cpu->halted ? "halted " : "running");
}
trace_gdbstub_op_extra_info((char *)mem_buf);
memtohex(buf, mem_buf, len);
put_packet(s, buf);
{
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;
}
#ifdef CONFIG_USER_ONLY
else if (strcmp(p, "Offsets") == 0) {
TaskState *ts = s->c_cpu->opaque;
snprintf(buf, sizeof(buf),
"Text=" TARGET_ABI_FMT_lx ";Data=" TARGET_ABI_FMT_lx
";Bss=" TARGET_ABI_FMT_lx,
ts->info->code_offset,
ts->info->data_offset,
ts->info->data_offset);
put_packet(s, buf);
break;
}
#else /* !CONFIG_USER_ONLY */
else if (strncmp(p, "Rcmd,", 5) == 0) {
int len = strlen(p + 5);
if ((len % 2) != 0) {
put_packet(s, "E01");
break;
}
len = len / 2;
hextomem(mem_buf, p + 5, len);
mem_buf[len++] = 0;
qemu_chr_be_write(s->mon_chr, mem_buf, len);
put_packet(s, "OK");
break;
}
#endif /* !CONFIG_USER_ONLY */
if (is_query_packet(p, "Supported", ':')) {
snprintf(buf, sizeof(buf), "PacketSize=%x", MAX_PACKET_LENGTH);
cc = CPU_GET_CLASS(first_cpu);
if (cc->gdb_core_xml_file != NULL) {
pstrcat(buf, sizeof(buf), ";qXfer:features:read+");
}
if (strstr(p, "multiprocess+")) {
s->multiprocess = true;
}
pstrcat(buf, sizeof(buf), ";multiprocess+");
put_packet(s, buf);
break;
}
if (strncmp(p, "Xfer:features:read:", 19) == 0) {
const char *xml;
target_ulong total_len;
process = gdb_get_cpu_process(s, s->g_cpu);
cc = CPU_GET_CLASS(s->g_cpu);
if (cc->gdb_core_xml_file == NULL) {
goto unknown_command;
}
gdb_has_xml = true;
p += 19;
xml = get_feature_xml(s, p, &p, process);
if (!xml) {
snprintf(buf, sizeof(buf), "E00");
put_packet(s, buf);
break;
}
if (*p == ':')
p++;
addr = strtoul(p, (char **)&p, 16);
if (*p == ',')
p++;
len = strtoul(p, (char **)&p, 16);
total_len = strlen(xml);
if (addr > total_len) {
snprintf(buf, sizeof(buf), "E00");
put_packet(s, buf);
break;
}
if (len > (MAX_PACKET_LENGTH - 5) / 2)
len = (MAX_PACKET_LENGTH - 5) / 2;
if (len < total_len - addr) {
buf[0] = 'm';
len = memtox(buf + 1, xml + addr, len);
} else {
buf[0] = 'l';
len = memtox(buf + 1, xml + addr, total_len - addr);
}
put_packet_binary(s, buf, len + 1, true);
break;
}
if (is_query_packet(p, "Attached", ':')) {
put_packet(s, GDB_ATTACHED);
break;
}
/* Unrecognised 'q' command. */
goto unknown_command;
default:
unknown_command:
/* put empty packet */
buf[0] = '\0';
put_packet(s, buf);