import tempfile
import threading
import fcntl
+import commands
import logger
finally: f.close()
return temporary_filename
+# utilities functions to get (cached) information from the node
+
+# get node_id from /etc/planetlab/node_id and cache it
+_node_id=None
+def node_id():
+ global _node_id
+ if _node_id is None:
+ try:
+ _node_id=int(file("/etc/planetlab/node_id").read())
+ except:
+ _node_id=""
+ return _node_id
+
+# get slicefamily from /etc/planetlab/slicefamily and cache it
+# http://svn.planet-lab.org/wiki/SliceFamily
+_slicefamily=None
+def slicefamily():
+ global _slicefamily
+ if _slicefamily is None:
+ try:
+ _slicefamily=file("/etc/planetlab/slicefamily").read().strip()
+ except:
+ _slicefamily=""
+ return _slicefamily
+
+_root_context_arch=None
+def root_context_arch():
+ global _root_context_arch
+ if not _root_context_arch:
+ _root_context_arch=commands.getoutput("uname -i")
+ return _root_context_arch
+
class NMLock:
def __init__(self, file):
+ logger.log("Lock %s initialized." % file, 2)
self.fd = os.open(file, os.O_RDWR|os.O_CREAT, 0600)
flags = fcntl.fcntl(self.fd, fcntl.F_GETFD)
flags |= fcntl.FD_CLOEXEC
def __del__(self):
os.close(self.fd)
def acquire(self):
- fcntl.lockf(self.fd, fcntl.LOCK_EX)
+ logger.log("Lock acquired.", 2)
+ fcntl.lockf(self.fd, fcntl.LOCK_SH)
def release(self):
+ logger.log("Lock released.", 2)
fcntl.lockf(self.fd, fcntl.LOCK_UN)