fix possible IOError (pemission denied) 2 users are writing to the same log file

diff --git a/sfa/util/sfalogging.py b/sfa/util/sfalogging.py
index 3991d33..199066d 100755 (executable)
--- a/sfa/util/sfalogging.py
+++ b/sfa/util/sfalogging.py
@@ -28,6 +28,14 @@ class _SfaLogger:
             # This is usually a permissions error becaue the file is
             # owned by root, but httpd is trying to access it.
             tmplogfile=os.getenv("TMPDIR", "/tmp") + os.path.sep + os.path.basename(logfile)
+            # In strange uses, 2 users on same machine might use same code,
+            # meaning they would clobber each others files
+            # We could (a) rename the tmplogfile, or (b)
+            # just log to the console in that case.
+            # Here we default to the console.
+            if os.path.exists(tmplogfile) and not os.access(tmplogfile,os.W_OK):
+                loggername = loggername + "-console"
+                handler = logging.StreamHandler()
             handler=logging.handlers.RotatingFileHandler(tmplogfile,maxBytes=1000000, backupCount=5) 
         handler.setFormatter(logging.Formatter("%(asctime)s - %(levelname)s - %(message)s"))
         self.logger=logging.getLogger(loggername)