Changeset 1511

Timestamp:

Mar 4, 2014 10:27:24 AM (10 years ago)

Author:

kpetersn

Message:

Use fcntl.flock instead of fuser to determine if a workspace is locked to allow startCSS.py to correctly detect locked workspaces when running as the same user on different computers with a shared home directory.

File:

• cssboy_deployment/src/startCSS.py (modified) (5 diffs)

cssboy_deployment/src/startCSS.py

@@ -13 +13 @@
 
 import os
+import fcntl
 
 def main():
@@ -20 +21 @@
   except KeyError:
     print "CSS_WORKSPACES environment variable is undefined."
-        return
+    return
 
   # Verify that the CSS workspace diretory exists
@@ -37 +38 @@
   if not os.path.isfile(css_bin):
     print "CSS_BIN=%s doesn't exist." % css_bin
-    return
-  
-  # Get the location of the fuser binary
-  fuser_bin = which('fuser')
-  if fuser_bin == None:
-    print "'fuser' command not found"
     return
   
@@ -68 +63 @@
     lock_path = workspace + os.sep + '.metadata' + os.sep + '.lock'
   
-    cmd_str = "%s -s %s" % (fuser_bin, lock_path)
-    ret_val = os.system(cmd_str)
-  
+    if os.path.isfile(lock_path):
+      # Lock file exists
+      
+      lfd = open(lock_path, 'r+')
+      
+      # Determine if lock file is locked by trying to lock it
+      try:
+        fcntl.flock(lfd, fcntl.LOCK_EX | fcntl.LOCK_NB)
+      except:
+        # The file is locked
+        ret_val = 0
+      else:
+        # The file is NOT locked.
+        fcntl.flock(lfd, fcntl.LOCK_UN)
+        ret_val = 1
+      
+      lfd.close()
+      
+    else:
+      # lock file doesn't exist, workspace should be available
+      ret_val = 1
+
     #print "  ", os.path.basename(workspace), ret_val
     print "  ", os.path.basename(workspace)
@@ -91 +105 @@
 
 
-# http://stackoverflow.com/questions/377017/test-if-executable-exists-in-python
-def which(program):
-    import os
-    def is_exe(fpath):
-        return os.path.isfile(fpath) and os.access(fpath, os.X_OK)
-
-    fpath, fname = os.path.split(program)
-    if fpath:
-        if is_exe(program):
-            return program
-    else:
-        for path in os.environ["PATH"].split(os.pathsep):
-            exe_file = os.path.join(path, program)
-            if is_exe(exe_file):
-                return exe_file
-
-    return None
-
 if __name__ == '__main__':
   main()