Python: Remove Win32 support from FileHandle

Removes supporting Win32 from FileHandle. FileHandle was designed
to manage opening & closing its own file reference. Python does
not provide a public API to open a file which returns a Win32 handle.
This leads to a contrived process of opening a file, getting a file
descriptor, and converting it to a Win32 handle. To be clear,
os.open() on Windows provides a POSIX FD.

FileHandle does not currently support a user providing an already
open file resource, which at this time seems to be the only
plausible use case of a Win32 handle being used.

For the sake of simplicity and getting out an initial release, we
will just error if the OPAQUE_WIN32 handle type is set.

(This however will leave Win32 support in the Cython layer as that
is a trivial switch that gets passed into the C library.)

Author: riley-dixon

python/hipfile/_hipfile.pyx

@@ -163,13 +163,13 @@ def hipFileGetVersion():
 #  File handles
 # ---------------------------------------------------------------------------
 
-def hipFileHandleRegister(int fd, int handle_type):
+def hipFileHandleRegister(uintptr_t handle_value, int handle_type):
     """Wrapper for ``hipFileHandleRegister``.
 
     Parameters
     ----------
-    fd : int
-        POSIX file descriptor.
+    handle_value : int
+        POSIX file descriptor or Win32 HANDLE, depending on *handle_type*.
     handle_type : int
         Value from ``hipFileFileHandleType_t``.
 
@@ -180,7 +180,10 @@ def hipFileHandleRegister(int fd, int handle_type):
     cdef _c.hipFileDescr_t descr
     memset(&descr, 0, sizeof(descr))
     descr.type = <_c.hipFileFileHandleType_t>handle_type
-    descr.fd = fd
+    if handle_type == <int>_c.hipFileHandleTypeOpaqueWin32:
+        descr.hFile = <void *>handle_value
+    else:
+        descr.fd = <int>handle_value
     cdef _c.hipFileError_t e = _c.hipFileHandleRegister(&fh, &descr)
     return (<uintptr_t>fh, _err(e))
 

python/hipfile/file.py

@@ -11,17 +11,10 @@
 from hipfile.enums import FileHandleType
 from hipfile.error import HipFileException
 
-default_handle_type = None
-if os.name == "posix":
-    default_handle_type = FileHandleType.OPAQUE_FD
-elif os.name == "nt":
-    default_handle_type = FileHandleType.OPAQUE_WIN32
-
-
 class FileHandle:
     DEFAULT_MODE = stat.S_IRUSR | stat.S_IWUSR | stat.S_IRGRP | stat.S_IROTH
 
-    def __init__(self, path, flags, mode=DEFAULT_MODE, handle_type=default_handle_type):
+    def __init__(self, path, flags, mode=DEFAULT_MODE, handle_type=FileHandleType.OPAQUE_FD):
         self._fd = None
         self._flags = flags
         self._handle = None
@@ -55,8 +48,12 @@ def handle_type(self):
 
     @handle_type.setter
     def handle_type(self, _handle_type):
+        if self._handle is not None:
+            raise RuntimeError("Cannot modify handle_type while FileHandle is open")
         if _handle_type not in FileHandleType:
             raise ValueError(f"'{_handle_type}' is not a member of enum FileHandleType")
+        if _handle_type == FileHandleType.OPAQUE_WIN32:
+            raise NotImplementedError(f"FileHandle does not currently support Win32 Handles")
         self._handle_type = _handle_type
 
     @property