[minion-cvs] Add new replaceContents method to Lockfile so that the ...

[nickm@seul.org (Nick Mathewson)]

Update of /home/minion/cvsroot/src/minion/lib/mixminion
In directory moria.mit.edu:/tmp/cvs-serv28868/lib/mixminion

Modified Files:
	Common.py 
Log Message:
Add new replaceContents method to Lockfile so that the pidfile can change its contents after locking and forking.

Index: Common.py
===================================================================
RCS file: /home/minion/cvsroot/src/minion/lib/mixminion/Common.py,v
retrieving revision 1.117
retrieving revision 1.118
diff -u -d -r1.117 -r1.118
--- Common.py	24 Nov 2003 19:59:04 -0000	1.117
+++ Common.py	25 Nov 2003 02:14:33 -0000	1.118
@@ -868,11 +868,8 @@
             self.addHandler(_ConsoleLogHandler(sys.stderr))
         else:
             self.setMinSeverity(config['Server'].get('LogLevel', "WARN"))
-            logfile = config['Server'].get('LogFile')
-            if logfile is None:
-                homedir = config['Server'].get('Homedir')
-                if homedir:
-                    logfile = os.path.join(homedir, "log")
+            #XXXX006 ensure parent.
+            logfile = config.getLogFile()
             self.addHandler(_ConsoleLogHandler(sys.stderr))
             if logfile:
                 try:
@@ -1443,7 +1440,7 @@
         """Return the contents of the lock file."""
         return readFile(self.filename)
 
-    def acquire(self, contents="", blocking=0):
+    def acquire(self, contents="", blocking=0, mode=0600):
         """Acquire this lock.  If we're acquiring the lock for the first time,
            write 'contents' to the lockfile.  If 'blocking' is true, wait
            until we can acquire the lock.  If 'blocking' is false, raise
@@ -1454,7 +1451,7 @@
             return
 
         assert self.fd is None
-        self.fd = os.open(self.filename, os.O_RDWR|os.O_CREAT, 0600)
+        self.fd = os.open(self.filename, os.O_RDWR|os.O_CREAT, mode)
         try:
             self._lock(self.fd, blocking)
             self.count += 1
@@ -1464,6 +1461,16 @@
             os.close(self.fd)
             self.fd = None
             raise
+
+    def replaceContents(self, contents):
+        """Replace the current contents of the lockfile with 'contents',
+           without releasing the lock.  Invokers must hold the lock."""
+        assert self.count > 0 and self.fd is not None
+        SEEK_SET = 0
+        os.lseek(self.fd, 0, SEEK_SET)
+        os.ftruncate(self.fd, 0)
+        os.write(self.fd, contents)
+        os.fsync(self.fd)
 
     def release(self):
         """Release the lock."""