1 files changed, 156 insertions, 0 deletions
diff --git a/tools/python/xen/xend/XendRoot.py b/tools/python/xen/xend/XendRoot.py
new file mode 100644
index 0000000000..665f5df29e
--- /dev/null
+++ b/tools/python/xen/xend/XendRoot.py
@@ -0,0 +1,156 @@
+# Copyright (C) 2004 Mike Wray <mike.wray@hp.com>
+
+"""Xend root class.
+Creates the event server and handles configuration.
+"""
+
+import os
+import os.path
+import sys
+import EventServer
+
+# Initial create of the event server.
+eserver = EventServer.instance()
+
+import sxp
+
+def reboots():
+    """Get a list of system reboots from wtmp.
+    """
+    out = os.popen('/usr/bin/last reboot', 'r')
+    list = [ x.strip() for x in out if x.startswith('reboot') ]
+    return list
+
+def last_reboot():
+    """Get the last known system reboot.
+    """
+    l = reboots()
+    return (l and l[-1]) or None
+
+class XendRoot:
+    """Root of the management classes."""
+
+    lastboot_default = "/var/xen/lastboot"
+
+    """Default path to the root of the database."""
+    dbroot_default = "/var/xen/xend-db"
+
+    """Default path to the config file."""
+    config_default = "/etc/xen/xend-config.sxp"
+
+    """Environment variable used to override config_default."""
+    config_var     = "XEND_CONFIG"
+
+    def __init__(self):
+        self.rebooted = 0
+        self.last_reboot = None
+        self.dbroot = None
+        self.config_path = None
+        self.config = None
+        self.configure()
+        self.check_lastboot()
+        eserver.subscribe('xend.*', self.event_handler)
+        #eserver.subscribe('xend.domain.created', self.event_handler)
+        #eserver.subscribe('xend.domain.died', self.event_handler)
+
+    def start(self):
+        eserver.inject('xend.start', self.rebooted)
+
+    def event_handler(self, event, val):
+        print >> sys.stderr, "EVENT>", event, val
+
+    def read_lastboot(self):
+        try:
+            val = file(self.lastboot, 'rb').readlines()[0]
+        except StandardError, ex:
+            print 'warning: Error reading', self.lastboot, ex
+            val = None
+        return val
+
+    def write_lastboot(self, val):
+        if not val: return
+        try:
+            fdir = os.path.dirname(self.lastboot)
+            if not os.path.isdir(fdir):
+                os.makedirs(fdir)
+            out = file(self.lastboot, 'wb+')
+            out.write(val)
+            out.close()
+        except IOError, ex:
+            print 'warning: Error writing', self.lastboot, ex
+            pass
+
+    def check_lastboot(self):
+        """Check if there has been a system reboot since we saved lastboot.
+        """
+        last_val = self.read_lastboot()
+        this_val = last_reboot()
+        if this_val == last_val:
+            self.rebooted = 0
+        else:
+            self.rebooted = 1
+            self.write_lastboot(this_val)
+        self.last_reboot = this_val
+
+    def get_last_reboot(self):
+        return self.last_reboot
+
+    def get_rebooted(self):
+        return self.rebooted
+
+    def configure(self):
+        self.set_config()
+        self.dbroot = self.get_config_value("dbroot", self.dbroot_default)
+        self.lastboot = self.get_config_value("lastboot", self.lastboot_default)
+
+    def get_dbroot(self):
+        """Get the path to the database root.
+        """
+        return self.dbroot
+
+    def set_config(self):
+        """If the config file exists, read it. If not, ignore it.
+
+        The config file is a sequence of sxp forms.
+        """
+        self.config_path = os.getenv(self.config_var, self.config_default)
+        if os.path.exists(self.config_path):
+            fin = file(self.config_path, 'rb')
+            try:
+                config = sxp.parse(fin)
+                config.insert(0, 'config')
+                self.config = config
+            finally:
+                fin.close()
+        else:
+            self.config = ['config']
+
+    def get_config(self, name=None):
+        """Get the configuration element with the given name, or
+        the whole configuration if no name is given.
+
+        name	element name (optional)
+        returns config or none
+        """
+        if name is None:
+            val = self.config
+        else:
+            val = sxp.child(self.config, name)
+        return val
+
+    def get_config_value(self, name, val=None):
+        """Get the value of an atomic configuration element.
+
+        name	element name
+        val	default value (optional, defaults to None)
+        returns value
+        """
+        return sxp.child_value(self.config, name, val=val)
+
+def instance():
+    global inst
+    try:
+        inst
+    except:
+        inst = XendRoot()
+    return inst