[Qemu-devel] [PATCH v3 09/18] Revert "qjson: Simplify by using json-output-visitor"

[Eric Blake]

Showing two alternative approaches; revert approach 1 to
go forward with approach 2

This reverts commit 7af47db0b00e982231399a81a3af490d84aee010.
---
 qjson.c | 61 +++++++++++++++++++++++++++++++++++++++----------------------
 1 file changed, 39 insertions(+), 22 deletions(-)

diff --git a/qjson.c b/qjson.c
index 17cc962..d172b1f 100644
--- a/qjson.c
+++ b/qjson.c
@@ -12,85 +12,102 @@
  */

 #include "qemu/osdep.h"
+#include <qapi/qmp/qstring.h>
+#include <glib.h>
 #include <qjson.h>
 #include <qemu/module.h>
 #include <qom/object.h>
-#include "qapi/json-output-visitor.h"
-#include "qapi/error.h"

 struct QJSON {
     Object obj;
-    JsonOutputVisitor *jov;
-    char *str;
+    QString *str;
+    bool omit_comma;
 };

 #define QJSON(obj) OBJECT_CHECK(QJSON, (obj), TYPE_QJSON)

+static void json_emit_element(QJSON *json, const char *name)
+{
+    /* Check whether we need to print a , before an element */
+    if (json->omit_comma) {
+        json->omit_comma = false;
+    } else {
+        qstring_append(json->str, ", ");
+    }
+
+    if (name) {
+        qstring_append_json_string(json->str, name);
+        qstring_append(json->str, " : ");
+    }
+}
+
 void json_start_object(QJSON *json, const char *name)
 {
-    Visitor *v = json_output_get_visitor(json->jov);
-    visit_start_struct(v, name, NULL, 0, &error_abort);
+    json_emit_element(json, name);
+    qstring_append(json->str, "{ ");
+    json->omit_comma = true;
 }

 void json_end_object(QJSON *json)
 {
-    Visitor *v = json_output_get_visitor(json->jov);
-    visit_check_struct(v, &error_abort);
-    visit_end_struct(v);
+    qstring_append(json->str, " }");
+    json->omit_comma = false;
 }

 void json_start_array(QJSON *json, const char *name)
 {
-    Visitor *v = json_output_get_visitor(json->jov);
-    visit_start_list(v, name, NULL, 0, &error_abort);
+    json_emit_element(json, name);
+    qstring_append(json->str, "[ ");
+    json->omit_comma = true;
 }

 void json_end_array(QJSON *json)
 {
-    Visitor *v = json_output_get_visitor(json->jov);
-    visit_end_list(v);
+    qstring_append(json->str, " ]");
+    json->omit_comma = false;
 }

 void json_prop_int(QJSON *json, const char *name, int64_t val)
 {
-    Visitor *v = json_output_get_visitor(json->jov);
-    visit_type_int(v, name, &val, &error_abort);
+    json_emit_element(json, name);
+    qstring_append_format(json->str, "%" PRId64, val);
 }

 void json_prop_str(QJSON *json, const char *name, const char *str)
 {
-    Visitor *v = json_output_get_visitor(json->jov);
-    visit_type_str(v, name, (char **)&str, &error_abort);
+    json_emit_element(json, name);
+    qstring_append_json_string(json->str, str);
 }

 const char *qjson_get_str(QJSON *json)
 {
-    return json->str;
+    return qstring_get_str(json->str);
 }

 QJSON *qjson_new(void)
 {
     QJSON *json = QJSON(object_new(TYPE_QJSON));
-    json_start_object(json, NULL);
     return json;
 }

 void qjson_finish(QJSON *json)
 {
     json_end_object(json);
-    json->str = json_output_get_string(json->jov);
 }

 static void qjson_initfn(Object *obj)
 {
     QJSON *json = QJSON(obj);
-    json->jov = json_output_visitor_new();
+
+    json->str = qstring_from_str("{ ");
+    json->omit_comma = true;
 }

 static void qjson_finalizefn(Object *obj)
 {
     QJSON *json = QJSON(obj);
-    g_free(json->str);
+
+    qobject_decref(QOBJECT(json->str));
 }

 static const TypeInfo qjson_type_info = {
-- 
2.5.5