diff lockfile-0.10.2/lockfile/mkdirlockfile.py @ 33:7ceb967147c3

start xena with no gui add library files

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lockfile-0.10.2/lockfile/mkdirlockfile.py	Wed Jul 22 13:24:44 2015 -0700
@@ -0,0 +1,83 @@
+from __future__ import absolute_import, division
+
+import time
+import os
+import sys
+import errno
+
+from . import (LockBase, LockFailed, NotLocked, NotMyLock, LockTimeout,
+               AlreadyLocked)
+
+class MkdirLockFile(LockBase):
+    """Lock file by creating a directory."""
+    def __init__(self, path, threaded=True, timeout=None):
+        """
+        >>> lock = MkdirLockFile('somefile')
+        >>> lock = MkdirLockFile('somefile', threaded=False)
+        """
+        LockBase.__init__(self, path, threaded, timeout)
+        # Lock file itself is a directory.  Place the unique file name into
+        # it.
+        self.unique_name  = os.path.join(self.lock_file,
+                                         "%s.%s%s" % (self.hostname,
+                                                      self.tname,
+                                                      self.pid))
+
+    def acquire(self, timeout=None):
+        timeout = timeout is not None and timeout or self.timeout
+        end_time = time.time()
+        if timeout is not None and timeout > 0:
+            end_time += timeout
+
+        if timeout is None:
+            wait = 0.1
+        else:
+            wait = max(0, timeout / 10)
+
+        while True:
+            try:
+                os.mkdir(self.lock_file)
+            except OSError:
+                err = sys.exc_info()[1]
+                if err.errno == errno.EEXIST:
+                    # Already locked.
+                    if os.path.exists(self.unique_name):
+                        # Already locked by me.
+                        return
+                    if timeout is not None and time.time() > end_time:
+                        if timeout > 0:
+                            raise LockTimeout("Timeout waiting to acquire"
+                                              " lock for %s" %
+                                              self.path)
+                        else:
+                            # Someone else has the lock.
+                            raise AlreadyLocked("%s is already locked" %
+                                                self.path)
+                    time.sleep(wait)
+                else:
+                    # Couldn't create the lock for some other reason
+                    raise LockFailed("failed to create %s" % self.lock_file)
+            else:
+                open(self.unique_name, "wb").close()
+                return
+
+    def release(self):
+        if not self.is_locked():
+            raise NotLocked("%s is not locked" % self.path)
+        elif not os.path.exists(self.unique_name):
+            raise NotMyLock("%s is locked, but not by me" % self.path)
+        os.unlink(self.unique_name)
+        os.rmdir(self.lock_file)
+
+    def is_locked(self):
+        return os.path.exists(self.lock_file)
+
+    def i_am_locking(self):
+        return (self.is_locked() and
+                os.path.exists(self.unique_name))
+
+    def break_lock(self):
+        if os.path.exists(self.lock_file):
+            for name in os.listdir(self.lock_file):
+                os.unlink(os.path.join(self.lock_file, name))
+            os.rmdir(self.lock_file)