git-p4: Fix p4 user cache population on Windows.

diff --git a/contrib/fast-import/git-p4 b/contrib/fast-import/git-p4
index e3404ca853c8b54f1a0c64be7038d282746652a7..1f5a56ee7ffcedb854d84023fdf61570dcffe67e 100755 (executable)
--- a/contrib/fast-import/git-p4
+++ b/contrib/fast-import/git-p4
@@ -901,7 +901,8 @@ class P4Sync(Command):
                            % (labelDetails["label"], change))
 
     def getUserCacheFilename(self):
-        return os.environ["HOME"] + "/.gitp4-usercache.txt"
+        home = os.environ.get("HOME", os.environ.get("USERPROFILE"))
+        return home + "/.gitp4-usercache.txt"
 
     def getUserMapFromPerforceServer(self):
         if self.userMapFromPerforceServer: