Merge pull request #27785 from drodriguez/windows-update-checkout-symlink

[windows] Provide a symlink alternative for Windows.

Author: drodriguez

utils/update_checkout/update_checkout/update_checkout.py

@@ -400,6 +400,28 @@ def skip_list_for_platform(config):
     return skip_list
 
 
+# Python 2.7 in Windows doesn't support os.symlink
+os_symlink = getattr(os, "symlink", None)
+if callable(os_symlink):
+    pass
+else:
+    def symlink_ms(source, link_name):
+        source = os.path.normpath(source)
+        link_name = os.path.normpath(link_name)
+        if os.path.isdir(link_name):
+            os.rmdir(link_name)
+        elif os.exists(link_name):
+            os.remove(link_name)
+        import ctypes
+        csl = ctypes.windll.kernel32.CreateSymbolicLinkW
+        csl.argtypes = (ctypes.c_wchar_p, ctypes.c_wchar_p, ctypes.c_uint32)
+        csl.restype = ctypes.c_ubyte
+        flags = 1 if os.path.isdir(source) else 0
+        if csl(link_name, source, flags) == 0:
+            raise ctypes.WinError()
+    os.symlink = symlink_ms
+
+
 def symlink_llvm_monorepo(args):
     print("Create symlink for LLVM Project")
     llvm_projects = ['clang',