Added in a number of python exposed vserver constants.

[util-vserver.git] / python / vserver.py

diff --git a/python/vserver.py b/python/vserver.py
index da58e2a..1c85a94 100644 (file)
--- a/python/vserver.py
+++ b/python/vserver.py
@@ -17,6 +17,7 @@ import vserverimpl, vduimpl
 import cpulimit, bwlimit
 
 from vserverimpl import VS_SCHED_CPU_GUARANTEED as SCHED_CPU_GUARANTEED
+from vserverimpl import DLIMIT_INF
 
 
 
@@ -34,19 +35,23 @@ FLAGS_NAMESPACE = 128
 
 
 
+class NoSuchVServer(Exception): pass
+
+
+
 class VServer:
 
     INITSCRIPTS = [('/etc/rc.vinit', 'start'),
                    ('/etc/rc.d/rc', '%(runlevel)d')]
 
-    def __init__(self, name, vm_id, vm_running = False):
+    def __init__(self, name, vm_id = None, vm_running = False):
 
         self.name = name
         self.config_file = "/etc/vservers/%s.conf" % name
         self.dir = "%s/%s" % (vserverimpl.VSERVER_BASEDIR, name)
         if not (os.path.isdir(self.dir) and
                 os.access(self.dir, os.R_OK | os.W_OK | os.X_OK)):
-            raise Exception, "no such vserver: " + name
+            raise NoSuchVServer, "no such vserver: " + name
         self.config = {}
         for config_file in ["/etc/vservers.conf", self.config_file]:
             try:
@@ -55,6 +60,8 @@ class VServer:
                 if ex.errno != errno.ENOENT:
                     raise
         self.remove_caps = ~vserverimpl.CAP_SAFE;
+        if vm_id == None:
+            vm_id = int(self.config['S_CONTEXT'])
         self.ctx = vm_id
         self.vm_running = vm_running
 
@@ -79,11 +86,13 @@ class VServer:
         f.close()
         todo = newvars.copy()
         changed = False
+        offset = 0
         for m in self.config_var_re.finditer(data):
             (key, val) = m.groups()
             newval = todo.pop(key, None)
             if newval != None:
-                data = data[:m.start(2)] + str(newval) + data[m.end(2):]
+                data = data[:offset+m.start(2)] + str(newval) + data[offset+m.end(2):]
+                offset += len(str(newval)) - (m.end(2)-m.start(2))
                 changed = True
         for (newkey, newval) in todo.items():
             data += "%s=%s\n" % (newkey, newval)
@@ -98,14 +107,7 @@ class VServer:
         f.write(data)
         f.close()
 
-        # 'copy' original file, rename new to original
-        backup = filename + ".old"
-        try:
-            os.unlink(backup)
-        except OSError, ex:
-            if ex.errno != errno.ENOENT:
-                raise
-        os.link(filename, backup)
+        # replace old file with new
         os.rename(newfile, filename)
 
     def __do_chroot(self):
@@ -166,17 +168,25 @@ class VServer:
 
         return block_limit
 
-    def set_sched(self, cpu_share, sched_flags = 0):
+    def set_sched_config(self, cpu_share, sched_flags):
+
+        """ Write current CPU scheduler parameters to the vserver
+        configuration file. This method does not modify the kernel CPU
+        scheduling parameters for this context. """
 
         if cpu_share == int(self.config.get("CPULIMIT", -1)):
             return
         cpu_guaranteed = sched_flags & SCHED_CPU_GUARANTEED
-        #cpu_guaranteed = int(self.resources.get("nm_sched_flags",
-        #                                        None) == "guaranteed")
         cpu_config = { "CPULIMIT": cpu_share, "CPUGUARANTEED": cpu_guaranteed }
-        self.__update_config_file(self.config_file, cpu_config)
+        self.update_resources(cpu_config)
         if self.vm_running:
-            vserverimpl.setsched(self.ctx, cpu_share, sched_flags)
+            self.set_sched(cpu_share, sched_flags)
+
+    def set_sched(self, cpu_share, sched_flags = 0):
+
+        """ Update kernel CPU scheduling parameters for this context. """
+
+        vserverimpl.setsched(self.ctx, cpu_share, sched_flags)
 
     def get_sched(self):
         # have no way of querying scheduler right now on a per vserver basis
@@ -198,17 +208,23 @@ class VServer:
         ret = vserverimpl.getrlimit(self.ctx,6)
         return ret
 
-    def set_bwlimit(self, maxrate, minrate = 1, share = None, dev = "eth0"):
+    def set_bwlimit(self, minrate = bwlimit.bwmin, maxrate = None,
+                    exempt_min = None, exempt_max = None,
+                    share = None, dev = "eth0"):
 
-        if maxrate != 0:
-            bwlimit.on(self.ctx, dev, share, minrate, maxrate)
-        else:
+        if minrate is None:
             bwlimit.off(self.ctx, dev)
+        else:
+            bwlimit.on(self.ctx, dev, share,
+                       minrate, maxrate, exempt_min, exempt_max)
 
     def get_bwlimit(self, dev = "eth0"):
 
+        result = bwlimit.get(self.ctx)
         # result of bwlimit.get is (ctx, share, minrate, maxrate)
-        return bwlimit.get(self.ctx)[1:]
+        if result:
+            result = result[1:]
+        return result
 
     def open(self, filename, mode = "r", bufsize = -1):