From 2704efad514da6600481bef8686ddb786c10c62b Mon Sep 17 00:00:00 2001 From: Jon Doron Date: Wed, 29 May 2019 09:41:45 +0300 Subject: [PATCH] gdbstub: Implement generic set/query (Q/q pkt) with new infra MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 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 Message-Id: <20190529064148.19856-18-arilou@gmail.com> Signed-off-by: Alex Bennée --- gdbstub.c | 559 ++++++++++++++++++++++++++++++++++++------------------ 1 file changed, 373 insertions(+), 186 deletions(-) diff --git a/gdbstub.c b/gdbstub.c index 8864c3a392..6ccfec9ef3 100644 --- a/gdbstub.c +++ b/gdbstub.c @@ -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); - } - break; + { + static const GdbCmdParseEntry gen_set_cmd_desc = { + .handler = handle_gen_set, + .cmd = "Q", + .cmd_startswith = 1, + .schema = "s0" + }; + cmd_parser = &gen_set_cmd_desc; } -#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; - + break; default: - unknown_command: /* put empty packet */ buf[0] = '\0'; put_packet(s, buf);