From e9346f6b8228dfe469a702674f447ba53915f519 Mon Sep 17 00:00:00 2001
From: steffen123 <steffen@schaumburger.info>
Date: Sat, 10 Jul 2010 20:10:04 +0200
Subject: [PATCH] make it record source of lock holding, print if required this
 is mostly intended for devs

---
 pyfpdb/GuiBulkImport.py |  2 +-
 pyfpdb/fpdb.pyw         | 10 ++++++----
 pyfpdb/interlocks.py    |  9 ++++++++-
 3 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/pyfpdb/GuiBulkImport.py b/pyfpdb/GuiBulkImport.py
index a25db1d2..83f841e2 100755
--- a/pyfpdb/GuiBulkImport.py
+++ b/pyfpdb/GuiBulkImport.py
@@ -50,7 +50,7 @@ class GuiBulkImport():
         ttime = None
         # Does the lock acquisition need to be more sophisticated for multiple dirs?
         # (see comment above about what to do if pipe already open)
-        if self.settings['global_lock'].acquire(False):   # returns false immediately if lock not acquired
+        if self.settings['global_lock'].acquire(wait=False, source="GuiBulkImport"):   # returns false immediately if lock not acquired
             #try:
                 print "\nGlobal lock taken ..."
                 self.progressbar.set_text("Importing...")
diff --git a/pyfpdb/fpdb.pyw b/pyfpdb/fpdb.pyw
index d734e418..fc5e9fb6 100755
--- a/pyfpdb/fpdb.pyw
+++ b/pyfpdb/fpdb.pyw
@@ -814,12 +814,13 @@ class fpdb:
     def not_implemented(self, widget, data=None):
         self.warning_box("Unimplemented menu entry")
 
-    def obtain_global_lock(self):
-        ret = self.lock.acquire(False) # will return false if lock is already held
+    def obtain_global_lock(self, source):
+        ret = self.lock.acquire(source=source) # will return false if lock is already held
         if ret:
-            print "\nGlobal lock taken ..."
+            print "\nGlobal lock taken by", source
+            self.lockTakenBy=source
         else:
-            print "\nFailed to get global lock."
+            print "\nFailed to get global lock, it is currently held by", source
         return ret
         # need to release it later:
         # self.lock.release()
@@ -841,6 +842,7 @@ class fpdb:
 
     def release_global_lock(self):
         self.lock.release()
+        self.lockTakenBy=None
         print "Global lock released.\n"
 
     def tab_auto_import(self, widget, data=None):
diff --git a/pyfpdb/interlocks.py b/pyfpdb/interlocks.py
index 4e427e7d..f6ef7857 100755
--- a/pyfpdb/interlocks.py
+++ b/pyfpdb/interlocks.py
@@ -1,3 +1,4 @@
+# -*- coding: utf-8 -*-
 
 # Code from http://ender.snowburst.org:4747/~jjohns/interlocks.py
 # Thanks JJ!
@@ -34,19 +35,24 @@ class InterProcessLockBase:
         if not name:
             name = sys.argv[0]
         self.name = name
+        self.heldBy = None
 
     def getHashedName(self):
         return base64.b64encode(self.name).replace('=','')
 
     def acquire_impl(self, wait): abstract
         
-    def acquire(self, wait=False, retry_time=1):
+    def acquire(self, wait=False, retry_time=1, source=None):
+        if source == None:
+            source="Unknown"
         if self._has_lock:             # make sure 2nd acquire in same process fails
+            print "lock already held by:",self.heldBy
             return False
         while not self._has_lock:
             try:
                 self.acquire_impl(wait)
                 self._has_lock = True
+                self.heldBy=source
                 #print 'i have the lock'
             except SingleInstanceError:
                 if not wait:
@@ -58,6 +64,7 @@ class InterProcessLockBase:
     def release(self):
         self.release_impl()
         self._has_lock = False
+        self.heldBy=None
 
     def locked(self):
         if self.acquire():