From 92034d3d2f409da4b704fa004137b63e0741821c Mon Sep 17 00:00:00 2001
From: "J.A. de Jong - ASCEE" <j.a.dejong@ascee.nl>
Date: Tue, 7 Apr 2020 21:51:30 +0200
Subject: [PATCH] Running on Windows. WOOHOO!

---
 lasp/c/lasp_python.h | 22 ++++++++++++++++++++++
 lasp/wrappers.pyx    | 12 +++++++++---
 2 files changed, 31 insertions(+), 3 deletions(-)

diff --git a/lasp/c/lasp_python.h b/lasp/c/lasp_python.h
index 5b51cac..4ce31d6 100644
--- a/lasp/c/lasp_python.h
+++ b/lasp/c/lasp_python.h
@@ -17,6 +17,17 @@
 #define LASP_NUMPY_FLOAT_TYPE NPY_FLOAT32
 #endif
 
+#ifdef MS_WIN64
+/** 
+ * Function passed to Python to use for cleanup of
+ * foreignly obtained data.
+ **/
+static inline void capsule_cleanup(void* capsule) {
+	void *memory = PyCapsule_GetPointer(capsule, NULL);
+    free(memory);
+	}
+
+#endif
 /** 
  * Create a numpy array from an existing dmat.
  *
@@ -47,7 +58,18 @@ static inline PyObject* dmat_to_ndarray(dmat* mat,bool transfer_ownership) {
 
     if(transfer_ownership) {
         mat->_foreign_data = true;
+#ifdef MS_WIN64
+		// The default destructor of Python cannot free the data, as it is allocated
+		// with malloc. Therefore, with this code, we tell Numpy/Python to use
+		// the capsule_cleanup constructor. See:
+		// https://stackoverflow.com/questions/54269956/crash-of-jupyter-due-to-the-use-of-pyarray-enableflags/54278170#54278170
+		// Note that in general it was disadvised to build all C code with MinGW on Windows.
+		// We do it anyway, see if we find any problems on the way.
+		void* capsule = PyCapsule_New(mat->_data, NULL, capsule_cleanup);
+		PyArray_SetBaseObject( arr_t, capsule);
+#else		
         PyArray_ENABLEFLAGS(arr_t, NPY_OWNDATA);
+#endif
     }
 
     // Transpose the array
diff --git a/lasp/wrappers.pyx b/lasp/wrappers.pyx
index 4e0acd2..6d89325 100644
--- a/lasp/wrappers.pyx
+++ b/lasp/wrappers.pyx
@@ -2,6 +2,12 @@
 This file contains the Cython wrapper functions to C implementations.
 """
 include "config.pxi"
+from libc.stdio cimport printf
+from numpy cimport import_array
+
+import_array()
+
+
 IF LASP_FLOAT == "double":
     ctypedef  double d
     ctypedef double complex c
@@ -456,13 +462,13 @@ cdef class SosFilterBank:
         cdef dmat output
         with nogil:
             output = Sosfilterbank_filter(self.fb,&input_vd)
-
+        #printf('Came back from filter\n')
         # Steal the pointer from output
         result = dmat_to_ndarray(&output,True)
-
+        #printf('Converted to array\n')
         dmat_free(&output)
         vd_free(&input_vd)
-
+        #printf('Ready to return\n')
         return result
 
 cdef extern from "lasp_decimation.h":