[json-glib] core: Add json_parser_steal_root()

[Emmanuele Bassi <ebassi src gnome org>]

commit 0f6e3d3eddc3bdb321283998924506d9184a0a2a
Author: Ole André Vadla Ravnås <oleavr gmail com>
Date:   Tue Mar 14 18:27:13 2017 +0100

    core: Add json_parser_steal_root()
    
    This avoids copying the root node for the parse-to-node use-case.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=774688

 doc/json-glib-sections.txt |    1 +
 json-glib/json-parser.c    |   26 ++++++++++++++++++++++++++
 json-glib/json-parser.h    |    2 ++
 3 files changed, 29 insertions(+), 0 deletions(-)
---
diff --git a/doc/json-glib-sections.txt b/doc/json-glib-sections.txt
index c3152ab..047f03e 100644
--- a/doc/json-glib-sections.txt
+++ b/doc/json-glib-sections.txt
@@ -186,6 +186,7 @@ json_parser_load_from_stream_finish
 
 <SUBSECTION>
 json_parser_get_root
+json_parser_steal_root
 
 <SUBSECTION>
 json_parser_get_current_line
diff --git a/json-glib/json-parser.c b/json-glib/json-parser.c
index dda3eeb..f2a99d9 100644
--- a/json-glib/json-parser.c
+++ b/json-glib/json-parser.c
@@ -1198,6 +1198,32 @@ json_parser_get_root (JsonParser *parser)
 }
 
 /**
+ * json_parser_steal_root:
+ * @parser: a #JsonParser
+ *
+ * Steals the top level node from the parsed JSON stream.
+ *
+ * Returns: (transfer full): the top level #JsonNode
+ *
+ * Since: 1.4
+ */
+JsonNode *
+json_parser_steal_root (JsonParser *parser)
+{
+  JsonParserPrivate *priv;
+  JsonNode *root;
+
+  g_return_val_if_fail (JSON_IS_PARSER (parser), NULL);
+
+  priv = parser->priv;
+
+  root = priv->root;
+  priv->root = NULL;
+
+  return root;
+}
+
+/**
  * json_parser_get_current_line:
  * @parser: a #JsonParser
  *
diff --git a/json-glib/json-parser.h b/json-glib/json-parser.h
index c7223d2..1470fbf 100644
--- a/json-glib/json-parser.h
+++ b/json-glib/json-parser.h
@@ -176,6 +176,8 @@ gboolean    json_parser_load_from_stream_finish (JsonParser           *parser,
 
 JSON_AVAILABLE_IN_1_0
 JsonNode *  json_parser_get_root                (JsonParser           *parser);
+JSON_AVAILABLE_IN_1_4
+JsonNode *  json_parser_steal_root              (JsonParser           *parser);
 
 JSON_AVAILABLE_IN_1_0
 guint       json_parser_get_current_line        (JsonParser           *parser);