lit/TestRunner.py: [Win32] Rework WinWaitReleased() again! "win32file" from Python Win32 Extensions.

We can simply confirm the handle released to open it with EXCLUSIVE. Attempting renaming was bad.

Disable win32file at ImportError. Thanks to Francois to let me know.

FIXME: Could we report warning or notification if win32file were not found?

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153172 91177308-0d34-0410-b5e6-96231b3b80d8

utils/lit/lit/TestRunner.py

@@ -23,42 +23,55 @@ kUseCloseFDs = not kIsWindows
 # Use temporary files to replace /dev/null on Windows.
 kAvoidDevNull = kIsWindows
 
+# Negate if win32file is not found.
+kHaveWin32File = kIsWindows
+
 def RemoveForce(f):
     try:
         os.remove(f)
     except OSError:
         pass
 
-def WinRename(f_o, f_n):
-    import time
-    retry_cnt = 256
-    while (True):
-        try:
-            os.rename(f_o, f_n)
-            break
-        except WindowsError, (winerror, strerror):
-            retry_cnt = retry_cnt - 1
-            if retry_cnt <= 0:
-                raise
-            elif winerror == 32: # ERROR_SHARING_VIOLATION
-                time.sleep(0.01)
-            else:
-                raise
-
 def WinWaitReleased(f):
-    import random
-    t = "%s%06d" % (f, random.randint(0, 999999))
-    RemoveForce(t)
+    global kHaveWin32File
+    if not kHaveWin32File:
+        return
     try:
-        WinRename(f, t) # rename
-        WinRename(t, f) # restore
-    except WindowsError, (winerror, strerror):
-        if winerror in (2, 3):
-            # 2: ERROR_FILE_NOT_FOUND
-            # 3: ERROR_PATH_NOT_FOUND
-            pass
-        else:
-            raise
+        import time
+        import win32file, pywintypes
+        retry_cnt = 256
+        while True:
+            try:
+                h = win32file.CreateFile(
+                    f,
+                    win32file.GENERIC_READ,
+                    0, # Exclusive
+                    None,
+                    win32file.OPEN_EXISTING,
+                    win32file.FILE_ATTRIBUTE_NORMAL,
+                    None)
+                h.close()
+                return
+            except WindowsError, (winerror, strerror):
+                retry_cnt = retry_cnt - 1
+                if retry_cnt <= 0:
+                    raise
+                elif winerror == 32: # ERROR_SHARING_VIOLATION
+                    pass
+                else:
+                    raise
+            except pywintypes.error, e:
+                retry_cnt = retry_cnt - 1
+                if retry_cnt <= 0:
+                    raise
+                elif e[0]== 32: # ERROR_SHARING_VIOLATION
+                    pass
+                else:
+                    raise
+            time.sleep(0.01)
+    except ImportError, e:
+        kHaveWin32File = False
+        return
 
 def executeCommand(command, cwd=None, env=None):
     p = subprocess.Popen(command, cwd=cwd,