wrap-json: Add clone facility

This adds 3 new facilities:

 - wrap_json_clone: clones any json object superficially
 - wrap_json_clone_deep: clones any json object deeply
 - wrap_json_add: adds to an object the fields of an other object

Change-Id: I3844d972aa6477c9dde6f66ad0b0604284a853a7
Signed-off-by: José Bollo <jose.bollo@iot.bzh>

3 files changed, 97 insertions, 1 deletions

diff --git a/wrap-json.c b/wrap-json.c
index eace887..e5090ac 100644
--- a/wrap-json.c
+++ b/wrap-json.c
@@ -17,6 +17,7 @@
 */
 
 #include <string.h>
+#include <limits.h>
 
 #include "wrap-json.h"
 
@@ -913,9 +914,92 @@ void wrap_json_for_all(struct json_object *object, void (*callback)(void*,struct
 	}
 }
 
+static struct json_object *clone_any(struct json_object *object, int deep);
+
+static struct json_object *clone_object(struct json_object *object, int subdeep)
+{
+	struct json_object *r = json_object_new_object();
+	struct json_object_iterator it = json_object_iter_begin(object);
+	struct json_object_iterator end = json_object_iter_end(object);
+	while (!json_object_iter_equal(&it, &end)) {
+		json_object_object_add(r,
+			json_object_iter_peek_name(&it),
+			clone_any(json_object_iter_peek_value(&it), subdeep));
+		json_object_iter_next(&it);
+	}
+	return r;
+}
+
+static struct json_object *clone_array(struct json_object *object, int subdeep)
+{
+	int n = json_object_array_length(object);
+	struct json_object *r = json_object_new_array();
+	while (n) {
+		n--;
+		json_object_array_put_idx(r, n,
+			clone_any(json_object_array_get_idx(object, n), subdeep));
+	}
+	return r;
+}
+
+static struct json_object *clone_any(struct json_object *object, int deep)
+{
+	if (deep) {
+		switch (json_object_get_type(object)) {
+		case json_type_object:
+			return clone_object(object, deep - 1);
+		case json_type_array:
+			return clone_array(object, deep - 1);
+		default:
+			break;
+		}
+	}
+	return json_object_get(object);
+}
+
+struct json_object *wrap_json_clone(struct json_object *object)
+{
+	return clone_any(object, 1);
+}
+
+struct json_object *wrap_json_clone_deep(struct json_object *object)
+{
+	return clone_any(object, INT_MAX);
+}
+
+void wrap_json_object_add(struct json_object *dest, struct json_object *added)
+{
+	struct json_object_iterator it, end;
+	if (json_object_is_type(dest, json_type_object) && json_object_is_type(added, json_type_object)) {
+		it = json_object_iter_begin(added);
+		end = json_object_iter_end(added);
+		while (!json_object_iter_equal(&it, &end)) {
+			json_object_object_add(dest,
+				json_object_iter_peek_name(&it),
+				json_object_get(json_object_iter_peek_value(&it)));
+			json_object_iter_next(&it);
+		}
+	}
+}
+
 #if defined(WRAP_JSON_TEST)
 #include <stdio.h>
 
+void tclone(struct json_object *obj)
+{
+	struct json_object *o;
+
+	o = wrap_json_clone(obj);
+	if (strcmp(json_object_to_json_string(obj), json_object_to_json_string(o)))
+		printf("ERROR in clone: %s VERSUS %s\n", json_object_to_json_string(obj), json_object_to_json_string(o));
+	json_object_put(o);
+
+	o = wrap_json_clone_deep(obj);
+	if (strcmp(json_object_to_json_string(obj), json_object_to_json_string(o)))
+		printf("ERROR in clone_deep: %s VERSUS %s\n", json_object_to_json_string(obj), json_object_to_json_string(o));
+	json_object_put(o);
+}
+
 void p(const char *desc, ...)
 {
 	int rc;
@@ -929,6 +1013,7 @@ void p(const char *desc, ...)
 		printf("  SUCCESS %s\n\n", json_object_to_json_string(result));
 	else
 		printf("  ERROR[char %d err %d] %s\n\n", wrap_json_get_error_position(rc), wrap_json_get_error_code(rc), wrap_json_get_error_string(rc));
+	tclone(result);
 	json_object_put(result);
 }
 
@@ -996,6 +1081,7 @@ void u(const char *value, const char *desc, ...)
 		va_end(args);
 		printf("\n\n");
 	}
+	tclone(obj);
 	json_object_put(obj);
 }
 
diff --git a/wrap-json.h b/wrap-json.h
index f5e6996..fd5b7c3 100644
--- a/wrap-json.h
+++ b/wrap-json.h
@@ -1,5 +1,5 @@
 /*
- Copyright (C) 2016, 2017 "IoT.bzh"
+ Copyright (C) 2016, 2017, 2018 "IoT.bzh"
 
  author: José Bollo <jose.bollo@iot.bzh>
 
@@ -48,6 +48,10 @@ extern void wrap_json_object_for_all(struct json_object *object, void (*callback
 extern void wrap_json_optobject_for_all(struct json_object *object, void (*callback)(void*,struct json_object*,const char*), void *closure);
 extern void wrap_json_for_all(struct json_object *object, void (*callback)(void*,struct json_object*,const char*), void *closure);
 
+extern struct json_object *wrap_json_clone(struct json_object *object);
+extern struct json_object *wrap_json_clone_deep(struct json_object *object);
+extern void wrap_json_object_add(struct json_object *dest, struct json_object *added);
+
 #ifdef __cplusplus
     }
 #endif
diff --git a/wrap-json.test.result b/wrap-json.test.result
index b7acbb5..0edaf75 100644
--- a/wrap-json.test.result
+++ b/wrap-json.test.result
@@ -394,6 +394,12 @@ unpack("{\"foo\":42}", "{s?isi!}", "baz", &xi[0], "foo", &xi[1])
 unpack("\"Pz8_Pz8_P2hlbGxvPj4-Pj4-Pg\"", "y", &xy[0], &xz[0])
   SUCCESS y/19:???????hello>>>>>>>
 
+unpack("\"\"", "y", &xy[0], &xz[0])
+  SUCCESS y/0:
+
+unpack("null", "y", &xy[0], &xz[0])
+  SUCCESS y/0:
+
 unpack("{\"foo\":\"Pz8_Pz8_P2hlbGxvPj4-Pj4-Pg\"}", "{s?y}", "foo", &xy[0], &xz[0])
   SUCCESS s:foo y/19:???????hello>>>>>>>