1 files changed, 82 insertions, 0 deletions
diff --git a/src/lib/Bcfg2/Server/FileMonitor/Fam.py b/src/lib/Bcfg2/Server/FileMonitor/Fam.py
new file mode 100644
index 000000000..1a00fffa0
--- /dev/null
+++ b/src/lib/Bcfg2/Server/FileMonitor/Fam.py
@@ -0,0 +1,82 @@
+""" Fam provides FAM support for file alteration events """
+
+import os
+import _fam
+import stat
+import logging
+from time import time
+from Bcfg2.Server.FileMonitor import FileMonitor
+
+logger = logging.getLogger(__name__)
+
+class Fam(FileMonitor):
+    __priority__ = 90
+
+    def __init__(self, ignore=None, debug=False):
+        FileMonitor.__init__(self, ignore=ignore, debug=debug)
+        self.fm = _fam.open()
+        self.users = {}
+
+    def fileno(self):
+        """Return fam file handle number."""
+        return self.fm.fileno()
+
+    def handle_event_set(self, _):
+        self.Service()
+
+    def handle_events_in_interval(self, interval):
+        now = time()
+        while (time() - now) < interval:
+            if self.Service():
+                now = time()
+
+    def AddMonitor(self, path, obj):
+        """Add a monitor to path, installing a callback to obj.HandleEvent."""
+        mode = os.stat(path)[stat.ST_MODE]
+        if stat.S_ISDIR(mode):
+            handle = self.fm.monitorDirectory(path, None)
+        else:
+            handle = self.fm.monitorFile(path, None)
+        self.handles[handle.requestID()] = handle
+        if obj != None:
+            self.users[handle.requestID()] = obj
+        return handle.requestID()
+
+    def Service(self, interval=0.50):
+        """Handle all fam work."""
+        count = 0
+        collapsed = 0
+        rawevents = []
+        start = time()
+        now = time()
+        while (time() - now) < interval:
+            if self.fm.pending():
+                while self.fm.pending():
+                    count += 1
+                    rawevents.append(self.fm.nextEvent())
+                now = time()
+        unique = []
+        bookkeeping = []
+        for event in rawevents:
+            if self.should_ignore(event):
+                continue
+            if event.code2str() != 'changed':
+                # process all non-change events
+                unique.append(event)
+            else:
+                if (event.filename, event.requestID) not in bookkeeping:
+                    bookkeeping.append((event.filename, event.requestID))
+                    unique.append(event)
+                else:
+                    collapsed += 1
+        for event in unique:
+            if event.requestID in self.users:
+                try:
+                    self.users[event.requestID].HandleEvent(event)
+                except:
+                    logger.error("Handling event for file %s" % event.filename,
+                                 exc_info=1)
+        end = time()
+        logger.info("Processed %s fam events in %03.03f seconds. %s coalesced" %
+                    (count, (end - start), collapsed))
+        return count