Use cmake_process_manifest_hook setup argument to clean destination folder

Delete DPCTLSyclInterface library shared objects from dpctl/ folder from previous
runs.

Monkey-patch skbuild.setuptools._copy_file to not follows symbolic links, to ensure
that versioned DPCTLSyclInterface ends up as the proper set of symbolic links pointing
to a single physical shared object file.

If symbolic links are followed, 3 identical copies of the library end up in the installation
folder. Downstream dpctl users may end up with several instances of the library in their
process space which may end up with errors is statuful functinality (queue manager) is used.

Author: oleksandr-pavlyk

setup.py

@@ -14,8 +14,14 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+import os.path
+import pathlib
+import shutil
+
+import skbuild
+import skbuild.setuptools_wrap
+import skbuild.utils
 from setuptools import find_packages
-from skbuild import setup
 
 import versioneer
 
@@ -29,7 +35,51 @@ def _get_cmdclass():
     return cmdclass
 
 
-setup(
+def cleanup_destination(cmake_manifest):
+    """Delete library files from dpctl/ folder before
+    letting skbuild copy them over to avoid errors.
+    """
+    _to_unlink = []
+    for fn in cmake_manifest:
+        bn = os.path.basename(fn)
+        # delete
+        if "DPCTLSyclInterface" in bn:
+            lib_fn = os.path.join("dpctl", bn)
+            if os.path.exists(lib_fn):
+                _to_unlink.append(lib_fn)
+    for fn in _to_unlink:
+        pathlib.Path(fn).unlink()
+    return cmake_manifest
+
+
+def _patched_copy_file(src_file, dest_file, hide_listing=True):
+    """Copy ``src_file`` to ``dest_file`` ensuring parent directory exists.
+
+    By default, message like `creating directory /path/to/package` and
+    `copying directory /src/path/to/package -> path/to/package` are displayed
+    on standard output. Setting ``hide_listing`` to False avoids message from
+    being displayed.
+
+    NB: Patched here to not follows symbolic links
+    """
+    # Create directory if needed
+    dest_dir = os.path.dirname(dest_file)
+    if dest_dir != "" and not os.path.exists(dest_dir):
+        if not hide_listing:
+            print("creating directory {}".format(dest_dir))
+        skbuild.utils.mkdir_p(dest_dir)
+
+    # Copy file
+    if not hide_listing:
+        print("copying {} -> {}".format(src_file, dest_file))
+    shutil.copyfile(src_file, dest_file, follow_symlinks=False)
+    shutil.copymode(src_file, dest_file, follow_symlinks=False)
+
+
+skbuild.setuptools_wrap._copy_file = _patched_copy_file
+
+
+skbuild.setup(
     name="dpctl",
     version=versioneer.get_version(),
     cmdclass=_get_cmdclass(),
@@ -54,4 +104,5 @@ def _get_cmdclass():
         "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
     ],
+    cmake_process_manifest_hook=cleanup_destination,
 )