shiboken: de-virtualize the Python files

Since a while, the virtualization of the Python helper modules
in Shiboken is successfully active.

This patch de-virtualizes the files by creating them under the
shiboken6 directory, but only after a successful first start
of shiboken/PySide. On subsequent runs, the unpacked files will stay.

This way, the files are still safe against configuration
problems. They are no longer safe against tampering. As
an advantage, they can now easily be modified, and source
code debugging will work, again.
A simple reset can be done by clearing the files.dir folder.

Task-number: PYSIDE-962
Change-Id: I7bc003388c4d8a424faab9d7a87908bc05c4ecfb
Fixes: PYSIDE-1994
Pick-to: 6.4
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>

1 files changed, 35 insertions, 1 deletions

diff --git a/sources/shiboken6/libshiboken/embed/signature_bootstrap.py b/sources/shiboken6/libshiboken/embed/signature_bootstrap.py
index c11a0367a..72c042b46 100644
--- a/sources/shiboken6/libshiboken/embed/signature_bootstrap.py
+++ b/sources/shiboken6/libshiboken/embed/signature_bootstrap.py
@@ -26,6 +26,7 @@ recursion_trap = 0
 import base64
 import importlib
 import io
+import os
 import sys
 import traceback
 import zipfile
@@ -71,11 +72,44 @@ def bootstrap():
             sys.exit(-1)
         target.remove(support_path)
 
-    target, support_path = prepare_zipfile()
+    # Here we decide if re we-incarnate the embedded files or use embedding.
+    incarnated = re_incarnate_files()
+    if incarnated:
+        target, support_path = sys.path, os.fspath(incarnated)
+    else:
+        target, support_path = prepare_zipfile()
+    # PYSIDE-962: pre-load needed after re_incarnate_files [Windows, Py3.7.9]
+    ensure_shibokensupport(target, support_path)
     with ensure_shibokensupport(target, support_path):
         from shibokensupport.signature import loader
     return loader
 
+# Newer functionality:
+# This function checks if the support directory exist and returns it.
+# If does not exist, we try to create it and return it.
+# Otherwise, we return None.
+
+def re_incarnate_files():
+    import shiboken6 as root
+    files_dir = Path(root.__file__).resolve().parent / "files.dir"
+    if files_dir.exists():
+        return files_dir
+
+    target, zip = prepare_zipfile()
+    names = (_ for _ in zip.zfile.namelist() if _.endswith(".py"))
+    try:
+        # first check mkdir to get an error when we cannot write.
+        files_dir.mkdir()
+    except os.error:
+        return None
+    try:
+        # Then check for a real error when unpacking the zip file.
+        zip.zfile.extractall(path=files_dir, members=names)
+        return files_dir
+    except Exception as e:
+        print('Exception:', e)
+        traceback.print_exc(file=sys.stdout)
+        raise
 
 # New functionality: Loading from a zip archive.
 # There exists the zip importer, but as it is written, only real zip files are