create plugin infrastructure. move all caching related stuff to plugins.

1 files changed, 107 insertions, 0 deletions

diff --git a/src/py-libs/plugins/root_cache.py b/src/py-libs/plugins/root_cache.py
new file mode 100644
index 0000000..add7b19
--- /dev/null
+++ b/src/py-libs/plugins/root_cache.py
@@ -0,0 +1,107 @@
+#!/usr/bin/python -tt
+# vim:expandtab:autoindent:tabstop=4:shiftwidth=4:filetype=python:textwidth=0:
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU Library General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+# Written by Seth Vidal
+# Sections taken from Mach by Thomas Vander Stichele
+# revised and adapted by Michael Brown
+
+# python library imports
+import fcntl
+import logging
+import os
+import time
+
+# our imports
+from mock.trace_decorator import traceLog
+import mock.util
+
+# set up logging, module options
+moduleLog = logging.getLogger("mock")
+requires_api_version = "1.0"
+
+# plugin entry point
+def init(rootObj, conf):
+    rootCache = RootCache(rootObj, conf)
+
+# classes
+class RootCache(object):
+    """caches root environment in a tarball"""
+    @traceLog(moduleLog)
+    def __init__(self, rootObj, conf):
+        self.rootObj = rootObj
+        self.root_cache_opts = conf
+        self.rootSharedCachePath = os.path.join(rootObj.cachedir, "root_cache")
+        self.rootCacheFile = os.path.join(self.rootSharedCachePath, "cache.tar.gz")
+        self.rootCacheLock = None
+        self.state = rootObj.state
+        self.rootdir = rootObj.rootdir
+        rootObj.rootCacheObj = self
+        rootObj.addHook("preinit", self._rootCachePreInitHook)
+        rootObj.addHook("postinit", self._rootCachePostInitHook)
+
+    # =============
+    # 'Private' API
+    # =============
+    @traceLog(moduleLog)
+    def _rootCacheLock(self, shared=1):
+        lockType = fcntl.LOCK_EX
+        if shared: lockType = fcntl.LOCK_SH
+        try:
+            fcntl.lockf(self.rootCacheLock.fileno(), lockType | fcntl.LOCK_NB)
+        except IOError, e:
+            oldState = self.state()
+            self.state("Waiting for rootcache lock")
+            fcntl.lockf(self.rootCacheLock.fileno(), lockType)
+            self.state(oldState)
+
+    @traceLog(moduleLog)
+    def _rootCacheUnlock(self):
+        fcntl.lockf(self.rootCacheLock.fileno(), fcntl.LOCK_UN)
+
+    @traceLog(moduleLog)
+    def _rootCachePreInitHook(self):
+        mock.util.mkdirIfAbsent(self.rootSharedCachePath)
+        # lock so others dont accidentally use root cache while we operate on it.
+        if self.rootCacheLock is None:
+            self.rootCacheLock = open(os.path.join(self.rootSharedCachePath, "rootcache.lock"), "a+")
+
+        # check cache age:
+        self.state("enabling root cache")
+        try:
+            statinfo = os.stat(self.rootCacheFile)
+            file_age_days = (time.time() - statinfo.st_ctime) / (60 * 60 * 24)
+            if file_age_days > self.root_cache_opts['max_age_days']:
+                os.unlink(self.rootCacheFile)
+        except OSError:
+            pass
+
+        if os.path.exists(self.rootCacheFile):
+            self.state("unpacking cache")
+            self._rootCacheLock()
+            mock.util.do("tar xzf %s -C %s" % (self.rootCacheFile, self.rootdir))
+            self._rootCacheUnlock()
+            self.chroot_setup_cmd = "update"
+            self.chrootWasCleaned = False
+
+    @traceLog(moduleLog)
+    def _rootCachePostInitHook(self):
+        # never rebuild cache unless it was a clean build.
+        if self.chrootWasCleaned:
+            self.state("creating cache")
+            self._rootCacheLock(shared=0)
+            mock.util.do("tar czf %s -C %s ." % (self.rootCacheFile, self.rootdir))
+            self._rootCacheUnlock()
+