Ensure that signature strings never overflow again

The signature module used to use large strings with the signatures
of all functions in a class. This can lead to an overflow in MSVC,
because the maximum string length funnily still is 32K unicode
characters.

This patch solves that by using a single string per function.
Instead of a huge string, a list of strings is passed to each class.

To prevent any runtime increase, the string list creation is deferred
until the actual usage. At initialization time only a ssize_t holding
the structure address is passed.

As a result, the signature module should be even slightly faster.

Task-number: PYSIDE-955
Change-Id: I99faf942a3cca03456928b8aec5e8a4b9924b8b2
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>

1 files changed, 2 insertions, 2 deletions

diff --git a/sources/shiboken2/libshiboken/basewrapper.cpp b/sources/shiboken2/libshiboken/basewrapper.cpp
index db65ec696..3a043d849 100644
--- a/sources/shiboken2/libshiboken/basewrapper.cpp
+++ b/sources/shiboken2/libshiboken/basewrapper.cpp
@@ -744,7 +744,7 @@ introduceWrapperType(PyObject *enclosingObject,
                      const char *typeName,
                      const char *originalName,
                      PyType_Spec *typeSpec,
-                     const char *signaturesString,
+                     const char *signatureStrings[],
                      ObjectDestructor cppObjDtor,
                      SbkObjectType *baseType,
                      PyObject *baseTypes,
@@ -765,7 +765,7 @@ introduceWrapperType(PyObject *enclosingObject,
         }
     }
     // PYSIDE-510: Here is the single change to support signatures.
-    if (SbkSpecial_Type_Ready(enclosingObject, reinterpret_cast<PyTypeObject *>(type), signaturesString) < 0)
+    if (SbkSpecial_Type_Ready(enclosingObject, reinterpret_cast<PyTypeObject *>(type), signatureStrings) < 0)
         return nullptr;
 
     initPrivateData(type);