gdbstub: Add infrastructure to parse cmd packets
Signed-off-by: Jon Doron <arilou@gmail.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20190529064148.19856-2-arilou@gmail.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
diff --git a/gdbstub.c b/gdbstub.c
index 17dcd91..22ee2de 100644
--- a/gdbstub.c
+++ b/gdbstub.c
@@ -1272,6 +1272,201 @@
return res;
}
+typedef union GdbCmdVariant {
+ const char *data;
+ uint8_t opcode;
+ unsigned long val_ul;
+ unsigned long long val_ull;
+ struct {
+ GDBThreadIdKind kind;
+ uint32_t pid;
+ uint32_t tid;
+ } thread_id;
+} GdbCmdVariant;
+
+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,
+ GdbCmdVariant *params, int *num_params)
+{
+ int curr_param;
+ const char *curr_schema, *curr_data;
+
+ *num_params = 0;
+
+ if (!schema) {
+ return 0;
+ }
+
+ curr_schema = schema;
+ curr_param = 0;
+ curr_data = data;
+ while (curr_schema[0] && curr_schema[1] && *curr_data) {
+ switch (curr_schema[0]) {
+ case 'l':
+ if (qemu_strtoul(curr_data, &curr_data, 16,
+ ¶ms[curr_param].val_ul)) {
+ return -EINVAL;
+ }
+ curr_param++;
+ curr_data = cmd_next_param(curr_data, curr_schema[1]);
+ break;
+ case 'L':
+ if (qemu_strtou64(curr_data, &curr_data, 16,
+ (uint64_t *)¶ms[curr_param].val_ull)) {
+ return -EINVAL;
+ }
+ curr_param++;
+ curr_data = cmd_next_param(curr_data, curr_schema[1]);
+ break;
+ case 's':
+ params[curr_param].data = curr_data;
+ curr_param++;
+ curr_data = cmd_next_param(curr_data, curr_schema[1]);
+ break;
+ case 'o':
+ params[curr_param].opcode = *(uint8_t *)curr_data;
+ curr_param++;
+ curr_data = cmd_next_param(curr_data, curr_schema[1]);
+ break;
+ case 't':
+ params[curr_param].thread_id.kind =
+ read_thread_id(curr_data, &curr_data,
+ ¶ms[curr_param].thread_id.pid,
+ ¶ms[curr_param].thread_id.tid);
+ curr_param++;
+ curr_data = cmd_next_param(curr_data, curr_schema[1]);
+ break;
+ case '?':
+ curr_data = cmd_next_param(curr_data, curr_schema[1]);
+ break;
+ default:
+ return -EINVAL;
+ }
+ curr_schema += 2;
+ }
+
+ *num_params = curr_param;
+ return 0;
+}
+
+typedef struct GdbCmdContext {
+ GDBState *s;
+ GdbCmdVariant *params;
+ int num_params;
+ uint8_t mem_buf[MAX_PACKET_LENGTH];
+ char str_buf[MAX_PACKET_LENGTH + 1];
+} GdbCmdContext;
+
+typedef void (*GdbCmdHandler)(GdbCmdContext *gdb_ctx, void *user_ctx);
+
+/*
+ * cmd_startswith -> cmd is compared using startswith
+ *
+ *
+ * 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;
+} GdbCmdParseEntry;
+
+static inline int startswith(const char *string, const char *pattern)
+{
+ return !strncmp(string, pattern, strlen(pattern));
+}
+
+static int process_string_cmd(
+ GDBState *s, void *user_ctx, const char *data,
+ const GdbCmdParseEntry *cmds, int num_cmds)
+ __attribute__((unused));
+
+static int process_string_cmd(GDBState *s, void *user_ctx, const char *data,
+ const GdbCmdParseEntry *cmds, int num_cmds)
+{
+ int i, schema_len, max_num_params = 0;
+ GdbCmdContext gdb_ctx;
+
+ 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) {
+ schema_len = strlen(cmd->schema);
+ if (schema_len % 2) {
+ return -2;
+ }
+
+ max_num_params = schema_len / 2;
+ }
+
+ gdb_ctx.params =
+ (GdbCmdVariant *)alloca(sizeof(*gdb_ctx.params) * max_num_params);
+ memset(gdb_ctx.params, 0, sizeof(*gdb_ctx.params) * max_num_params);
+
+ if (cmd_parse_params(&data[strlen(cmd->cmd)], cmd->schema,
+ gdb_ctx.params, &gdb_ctx.num_params)) {
+ return -1;
+ }
+
+ gdb_ctx.s = s;
+ cmd->handler(&gdb_ctx, user_ctx);
+ return 0;
+ }
+
+ return -1;
+}
+
static int gdb_handle_packet(GDBState *s, const char *line_buf)
{
CPUState *cpu;
