+\f
+static size_t
+json_string_serialized_length(const char *string)
+{
+ size_t length;
+ uint8_t c;
+
+ length = strlen("\"\"");
+
+ while ((c = *string++) != '\0') {
+ switch (c) {
+ case '"':
+ case '\\':
+ case '\b':
+ case '\f':
+ case '\n':
+ case '\r':
+ case '\t':
+ length += 2;
+ break;
+
+ default:
+ if (c >= 32) {
+ length++;
+ } else {
+ /* \uXXXX */
+ length += 6;
+ }
+ break;
+ }
+ }
+
+ return length;
+}
+
+static size_t
+json_object_serialized_length(const struct shash *object)
+{
+ size_t length = strlen("{}");
+
+ if (!shash_is_empty(object)) {
+ struct shash_node *node;
+
+ /* Commas and colons. */
+ length += 2 * shash_count(object) - 1;
+
+ SHASH_FOR_EACH (node, object) {
+ const struct json *value = node->data;
+
+ length += json_string_serialized_length(node->name);
+ length += json_serialized_length(value);
+ }
+ }
+
+ return length;
+}
+
+static size_t
+json_array_serialized_length(const struct json_array *array)
+{
+ size_t length = strlen("[]");
+
+ if (array->n) {
+ size_t i;
+
+ /* Commas. */
+ length += array->n - 1;
+
+ for (i = 0; i < array->n; i++) {
+ length += json_serialized_length(array->elems[i]);
+ }
+ }
+
+ return length;
+}
+
+/* Returns strlen(json_to_string(json, 0)), that is, the number of bytes in the
+ * JSON output by json_to_string() for 'json' when JSSF_PRETTY is not
+ * requested. (JSSF_SORT does not affect the length of json_to_string()'s
+ * output.) */
+size_t
+json_serialized_length(const struct json *json)
+{
+ switch (json->type) {
+ case JSON_NULL:
+ return strlen("null");
+
+ case JSON_FALSE:
+ return strlen("false");
+
+ case JSON_TRUE:
+ return strlen("true");
+
+ case JSON_OBJECT:
+ return json_object_serialized_length(json->u.object);
+
+ case JSON_ARRAY:
+ return json_array_serialized_length(&json->u.array);
+
+ case JSON_INTEGER:
+ return snprintf(NULL, 0, "%lld", json->u.integer);
+
+ case JSON_REAL:
+ return snprintf(NULL, 0, "%.*g", DBL_DIG, json->u.real);
+
+ case JSON_STRING:
+ return json_string_serialized_length(json->u.string);
+
+ case JSON_N_TYPES:
+ default:
+ NOT_REACHED();
+ }
+}