Fix crashes when creating large documents

Compact an object in regular intervals when inserting
data into it, to avoid the object becoming huge.
Compact an object/array before inserting into another
array or object.
Check that the document doesn't get so big it's overflowing
the internal data structures.

Task-number: QTBUG-29288
Change-Id: Id39d80dac1e7d5a11f40819f41b4b336bce16947
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/src/corelib/json/qjson_p.h b/src/corelib/json/qjson_p.h
index 81439a00ce..06885ad972 100644
--- a/src/corelib/json/qjson_p.h
+++ b/src/corelib/json/qjson_p.h
@@ -543,6 +543,9 @@ public:
 class Value
 {
 public:
+    enum {
+        MaxSize = (1<<27) - 1
+    };
     union {
         uint _dummy;
         qle_bitfield<0, 3> type;
@@ -564,7 +567,7 @@ public:
 
     bool isValid(const Base *b) const;
 
-    static int requiredStorage(const QJsonValue &v, bool *compressed);
+    static int requiredStorage(QJsonValue &v, bool *compressed);
     static uint valueToStore(const QJsonValue &v, uint offset);
     static void copyData(const QJsonValue &v, char *dest, bool compressed);
 };