From dd2a5c4a353d0feb6b7c1dbf081643a57f85fde5 Mon Sep 17 00:00:00 2001
From: Vassilii Khachaturov <vassilii@tarunz.org>
Date: Thu, 26 Dec 2013 18:45:18 +0200
Subject: [PATCH] 7327: clean up file open/lock/close code

In preparation for fixing the bug, discovered minor glitches
in the open/lock/close logic on error paths. Using the RAII syntax
for xml_file and removing redundant unlock-before-close.
---
 src/RecentFiles.py | 57 +++++++++++++++++++++-------------------------
 1 file changed, 26 insertions(+), 31 deletions(-)

diff --git a/src/RecentFiles.py b/src/RecentFiles.py
index f436edbae..dea9088e7 100644
--- a/src/RecentFiles.py
+++ b/src/RecentFiles.py
@@ -162,25 +162,23 @@ class RecentFiles(object):
         """
         Saves the current GRAMPS RecentFiles collection to the associated file.
         """
-        xml_file = file(os.path.expanduser(GRAMPS_FILENAME),'w')
-        if use_lock:
-            fcntl.lockf(xml_file,fcntl.LOCK_EX)
-        xml_file.write("<?xml version=\"1.0\" encoding=\"utf-8\"?>\n")
-        xml_file.write('<RecentFiles>\n')
-        index = 0
-        for item in self.gramps_recent_files:
-            index += 1
-            if index > MAX_GRAMPS_ITEMS:
-                break
-            xml_file.write('  <RecentItem>\n')
-            xml_file.write('    <Path><![CDATA[%s]]></Path>\n' % item.get_path())
-            xml_file.write('    <Name><![CDATA[%s]]></Name>\n' % item.get_name())
-            xml_file.write('    <Timestamp>%d</Timestamp>\n' % item.get_time())
-            xml_file.write('  </RecentItem>\n')
-        xml_file.write('</RecentFiles>\n')
-        if use_lock:
-            fcntl.lockf(xml_file,fcntl.LOCK_UN)
-        xml_file.close()
+        with open(os.path.expanduser(GRAMPS_FILENAME), 'w') as xml_file:
+            if use_lock:
+                fcntl.lockf(xml_file,fcntl.LOCK_EX)
+            xml_file.write("<?xml version=\"1.0\" encoding=\"utf-8\"?>\n")
+            xml_file.write('<RecentFiles>\n')
+            index = 0
+            for item in self.gramps_recent_files:
+                index += 1
+                if index > MAX_GRAMPS_ITEMS:
+                    break
+                xml_file.write('  <RecentItem>\n')
+                xml_file.write('    <Path><![CDATA[%s]]></Path>\n' % item.get_path())
+                xml_file.write('    <Name><![CDATA[%s]]></Name>\n' % item.get_name())
+                xml_file.write('    <Timestamp>%d</Timestamp>\n' % item.get_time())
+                xml_file.write('  </RecentItem>\n')
+            xml_file.write('</RecentFiles>\n')
+            # all advisory locks on a file are released on close
 
 #-------------------------------------------------------------------------
 #
@@ -196,19 +194,16 @@ class RecentParser(object):
         self.recent_files = []
 
         try:
-            xml_file = open(os.path.expanduser(GRAMPS_FILENAME))
-            if use_lock:
-                fcntl.lockf(xml_file,fcntl.LOCK_SH)
+            with open(os.path.expanduser(GRAMPS_FILENAME)) as xml_file:
+                if use_lock:
+                    fcntl.lockf(xml_file,fcntl.LOCK_SH)
 
-            p = ParserCreate()
-            p.StartElementHandler = self.startElement
-            p.EndElementHandler = self.endElement
-            p.CharacterDataHandler = self.characters
-            p.ParseFile(xml_file)
-
-            if use_lock:
-                fcntl.lockf(xml_file,fcntl.LOCK_UN)
-            xml_file.close()
+                p = ParserCreate()
+                p.StartElementHandler = self.startElement
+                p.EndElementHandler = self.endElement
+                p.CharacterDataHandler = self.characters
+                p.ParseFile(xml_file)
+            # all advisory locks on a file are released on close
         except:
             pass