gdbstub: Implement set_thread (H pkt) with new infra

Signed-off-by: Jon Doron <arilou@gmail.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20190529064148.19856-7-arilou@gmail.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
diff --git a/gdbstub.c b/gdbstub.c
index 25ee936..aad43c0 100644
--- a/gdbstub.c
+++ b/gdbstub.c
@@ -1564,6 +1564,51 @@
     gdb_continue(gdb_ctx->s);
 }
 
+static void handle_set_thread(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    CPUState *cpu;
+
+    if (gdb_ctx->num_params != 2) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    if (gdb_ctx->params[1].thread_id.kind == GDB_READ_THREAD_ERR) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    if (gdb_ctx->params[1].thread_id.kind != GDB_ONE_THREAD) {
+        put_packet(gdb_ctx->s, "OK");
+        return;
+    }
+
+    cpu = gdb_get_cpu(gdb_ctx->s, gdb_ctx->params[1].thread_id.pid,
+                      gdb_ctx->params[1].thread_id.tid);
+    if (!cpu) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    /*
+     * Note: This command is deprecated and modern gdb's will be using the
+     *       vCont command instead.
+     */
+    switch (gdb_ctx->params[0].opcode) {
+    case 'c':
+        gdb_ctx->s->c_cpu = cpu;
+        put_packet(gdb_ctx->s, "OK");
+        break;
+    case 'g':
+        gdb_ctx->s->g_cpu = cpu;
+        put_packet(gdb_ctx->s, "OK");
+        break;
+    default:
+        put_packet(gdb_ctx->s, "E22");
+        break;
+    }
+}
+
 static int gdb_handle_packet(GDBState *s, const char *line_buf)
 {
     CPUState *cpu;
@@ -1577,7 +1622,6 @@
     char thread_id[16];
     uint8_t *registers;
     target_ulong addr, len;
-    GDBThreadIdKind thread_kind;
     const GdbCmdParseEntry *cmd_parser = NULL;
 
     trace_gdbstub_io_command(line_buf);
@@ -1840,35 +1884,14 @@
             put_packet(s, "E22");
         break;
     case 'H':
-        type = *p++;
-
-        thread_kind = read_thread_id(p, &p, &pid, &tid);
-        if (thread_kind == GDB_READ_THREAD_ERR) {
-            put_packet(s, "E22");
-            break;
-        }
-
-        if (thread_kind != GDB_ONE_THREAD) {
-            put_packet(s, "OK");
-            break;
-        }
-        cpu = gdb_get_cpu(s, pid, tid);
-        if (cpu == NULL) {
-            put_packet(s, "E22");
-            break;
-        }
-        switch (type) {
-        case 'c':
-            s->c_cpu = cpu;
-            put_packet(s, "OK");
-            break;
-        case 'g':
-            s->g_cpu = cpu;
-            put_packet(s, "OK");
-            break;
-        default:
-             put_packet(s, "E22");
-             break;
+        {
+            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':