minor error fixes

src/runtime/native/ABI.cs

@@ -36,8 +36,8 @@ namespace Python.Runtime.Native
 
         static unsafe int GetRefCountOffset()
         {
-            IntPtr tempObject = Runtime.PyList_New(0);
-            IntPtr* tempPtr = (IntPtr*)tempObject;
+            using var tempObject = Runtime.PyList_New(0);
+            IntPtr* tempPtr = (IntPtr*)tempObject.DangerousGetAddress();
             int offset = 0;
             while(tempPtr[offset] != (IntPtr)1)
             {
@@ -45,7 +45,6 @@ namespace Python.Runtime.Native
                 if (offset > 100)
                     throw new InvalidProgramException("PyObject_HEAD could not be found withing reasonable distance from the start of PyObject");
             }
-            Runtime.XDecref(tempObject);
             return offset * IntPtr.Size;
         }
     }

src/runtime/pybuffer.cs

@@ -15,7 +15,7 @@ namespace Python.Runtime
         {
             _view = new Py_buffer();
 
-            if (Runtime.PyObject_GetBuffer(exporter.Handle, ref _view, (int)flags) < 0)
+            if (Runtime.PyObject_GetBuffer(exporter, out _view, (int)flags) < 0)
             {
                 throw PythonException.ThrowLastAsClrException();
             }
@@ -46,25 +46,25 @@ namespace Python.Runtime
         public int Dimensions => _view.ndim;
         public bool ReadOnly => _view._readonly;
         public IntPtr Buffer => _view.buf;
-        public string Format => _view.format;
+        public string? Format => _view.format;
 
         /// <summary>
         /// An array of length <see cref="Dimensions"/> indicating the shape of the memory as an n-dimensional array.
         /// </summary>
-        public long[] Shape { get; private set; }
+        public long[]? Shape { get; private set; }
 
         /// <summary>
         /// An array of length <see cref="Dimensions"/> giving the number of bytes to skip to get to a new element in each dimension.
         /// Will be null except when PyBUF_STRIDES or PyBUF_INDIRECT flags in GetBuffer/>.
         /// </summary>
-        public long[] Strides { get; private set; }
+        public long[]? Strides { get; private set; }
 
         /// <summary>
         /// An array of Py_ssize_t of length ndim. If suboffsets[n] >= 0,
         /// the values stored along the nth dimension are pointers and the suboffset value dictates how many bytes to add to each pointer after de-referencing.
         /// A suboffset value that is negative indicates that no de-referencing should occur (striding in a contiguous memory block).
         /// </summary>
-        public long[] SubOffsets { get; private set; }
+        public long[]? SubOffsets { get; private set; }
 
         private static char OrderStyleToChar(BufferOrderStyle order, bool eitherOneValid)
         {
@@ -162,7 +162,7 @@ namespace Python.Runtime
         /// If this function is used as part of a getbufferproc, exporter MUST be set to the exporting object and flags must be passed unmodified.Otherwise, exporter MUST be NULL.
         /// </remarks>
         /// <returns>On success, set view->obj to a new reference to exporter and return 0. Otherwise, raise PyExc_BufferError, set view->obj to NULL and return -1;</returns>
-        internal void FillInfo(IntPtr exporter, IntPtr buf, long len, bool _readonly, int flags)
+        internal void FillInfo(BorrowedReference exporter, IntPtr buf, long len, bool _readonly, int flags)
         {
             if (disposedValue)
                 throw new ObjectDisposedException(nameof(PyBuffer));
@@ -213,9 +213,19 @@ namespace Python.Runtime
             return copylen;
         }
 
+        ~PyBuffer()
+        {
+            this.Dispose();
+            Finalizer.Instance.AddFinalizedObject(ref _view.obj);
+        }
+
         private bool disposedValue = false; // To detect redundant calls
 
-        private void Dispose(bool disposing)
+        /// <summary>
+        /// Release the buffer view and decrement the reference count for view->obj. This function MUST be called when the buffer is no longer being used, otherwise reference leaks may occur.
+        /// It is an error to call this function on a buffer that was not obtained via <see cref="PyObject.GetBuffer"/>.
+        /// </summary>
+        public void Dispose()
         {
             if (!disposedValue)
             {
@@ -225,31 +235,13 @@ namespace Python.Runtime
                 // this also decrements ref count for _view->obj
                 Runtime.PyBuffer_Release(ref _view);
 
-                _exporter = null;
+                _exporter = null!;
                 Shape = null;
                 Strides = null;
                 SubOffsets = null;
 
                 disposedValue = true;
             }
-        }
-
-        ~PyBuffer()
-        {
-            if (disposedValue)
-            {
-                return;
-            }
-            Finalizer.Instance.AddFinalizedObject(ref _view.obj);
-        }
-
-        /// <summary>
-        /// Release the buffer view and decrement the reference count for view->obj. This function MUST be called when the buffer is no longer being used, otherwise reference leaks may occur.
-        /// It is an error to call this function on a buffer that was not obtained via <see cref="PyObject.GetBuffer"/>.
-        /// </summary>
-        public void Dispose()
-        {
-            Dispose(true);
             GC.SuppressFinalize(this);
         }
     }