[Qgis-developer] bug when calling QgsGeometry::setWkbAndOwnership from python (with patch)

Stefanie Tellex stefie10 at media.mit.edu
Tue Jun 3 08:54:22 EDT 2008


The attached patch (against r8576) fixes a bug I ran into when trying to 
call  QgsGeometry::setWkbAndOnwership from python.    When calling it 
from  python, the caller cannot release ownership of the input buffer, 
and I  would get a seg fault.   I put a wrapper around the method that 
makes a  copy before passing it to the C code.

There's no memory leak (I don't think), because python retains ownership
of the input string, and the qgsgeometry object owns the copy.


-------------- next part --------------
Index: qgis/qgis_unstable/python/core/qgsgeometry.sip
--- qgis.orig/qgis_unstable/python/core/qgsgeometry.sip	2008-05-02 13:23:54.000000000 -0400
+++ qgis/qgis_unstable/python/core/qgsgeometry.sip	2008-05-26 21:08:55.000000000 -0400
@@ -61,7 +61,12 @@
     // SIP: buffer will be transferred from python to C++
     // TODO: create pythonic interface that will receive wkb as a string
-    void setWkbAndOwnership(unsigned char * wkb /Transfer, Array/, size_t length /ArraySize/);
+    void setWkbAndOwnership(unsigned char * wkb /Array/, size_t length /ArraySize/);
+unsigned char * copy = (unsigned char * ) malloc(a1);
+memcpy(copy, a0, a1);
+sipCpp->setWkbAndOwnership(copy, a1);
        Returns the buffer containing this geometry in WKB format.

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