Index: trunk/web/templates/main.py
===================================================================
--- trunk/web/templates/main.py	(revision 182)
+++ trunk/web/templates/main.py	(revision 187)
@@ -16,5 +16,6 @@
 import getafsgroups
 
-sys.stderr = StringIO.StringIO()
+errio = StringIO.StringIO()
+sys.stderr = errio
 sys.path.append('/home/ecprice/.local/lib/python2.5/site-packages')
 
@@ -84,6 +85,14 @@
 MAX_VMS_ACTIVE = 4
 
-def getMachinesByOwner(owner):
-    """Return the machines owned by a given owner."""
+def getMachinesByOwner(user, machine=None):
+    """Return the machines owned by the same as a machine.
+    
+    If the machine is None, return the machines owned by the same
+    user.
+    """
+    if machine:
+        owner = machine.owner
+    else:
+        owner = user.username
     return Machine.select_by(owner=owner)
 
@@ -100,5 +109,5 @@
     if not on:
         return MAX_MEMORY_SINGLE
-    machines = getMachinesByOwner(user.username)
+    machines = getMachinesByOwner(user, machine)
     active_machines = [x for x in machines if g.uptimes[x]]
     mem_usage = sum([x.memory for x in active_machines if x != machine])
@@ -106,5 +115,5 @@
 
 def maxDisk(user, machine=None):
-    machines = getMachinesByOwner(user.username)
+    machines = getMachinesByOwner(user, machine)
     disk_usage = sum([sum([y.size for y in x.disks])
                       for x in machines if x != machine])
@@ -112,5 +121,5 @@
 
 def canAddVm(user):
-    machines = getMachinesByOwner(user.username)
+    machines = getMachinesByOwner(user)
     active_machines = [x for x in machines if g.uptimes[x]]
     return (len(machines) < MAX_VMS_TOTAL and
@@ -118,5 +127,15 @@
 
 def haveAccess(user, machine):
-    """Return whether a user has access to a machine"""
+    """Return whether a user has adminstrative access to a machine"""
+    if user.username == 'moo':
+        return True
+    if user.username in (machine.administrator, machine.owner):
+        return True
+    if checkAfsGroup(user, machine.administrator, 'athena.mit.edu'): #XXX Cell?
+        return True
+    return owns(user, machine)
+
+def owns(user, machine):
+    """Return whether a user owns a machine"""
     if user.username == 'moo':
         return True
@@ -573,7 +592,22 @@
     return Template(file="command.tmpl", searchList=[d, global_dict])
 
-def testOwner(user, owner, machine=None):
-    if owner == machine.owner:   #XXX What do we do when you lose access to the locker?
-        return owner
+def testAdmin(user, admin, machine):
+    if admin in (None, machine.administrator):
+        return None
+    if admin == user.username:
+        return admin
+    if getafsgroups.checkAfsGroup(user, admin, 'athena.mit.edu'):
+        return admin
+    if getafsgroups.checkAfsGroup(user, 'system:'+admin, 'athena.mit.edu'):
+        return 'system:'+admin
+    raise InvalidInput('admin', admin, 
+                       'You must control the group you move it to')
+    
+def testOwner(user, owner, machine):
+    if owner in (None, machine.owner):
+        return None
+    #XXX should you be able to transfer ownership if you don't already own it?
+    #if not owns(user, machine):
+    #    raise InvalidInput('owner', owner, "You don't own this machine, so you can't  transfer ownership")
     value = getafsgroups.checkLockerOwner(user.username, owner, verbose=True)
     if value == True:
@@ -582,4 +616,6 @@
 
 def testContact(user, contact, machine=None):
+    if contact in (None, machine.contact):
+        return None
     if not re.match("^[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,4}$", contact, re.I):
         raise InvalidInput('contact', contact, "Not a valid email")
@@ -590,9 +626,7 @@
 
 def testName(user, name, machine=None):
-    if name is None:
+    if name in (None, machine.name):
         return None
     if not Machine.select_by(name=name):
-        return name
-    if name == machine.name:
         return name
     raise InvalidInput('name', name, "Already taken")
@@ -618,7 +652,7 @@
         machine = testMachineId(user, fields.getfirst('machine_id'))
         owner = testOwner(user, fields.getfirst('owner'), machine)
-        contact = testContact(user, fields.getfirst('contact'))
-        hostname = testHostname(owner, fields.getfirst('hostname'),
-                                machine)
+        admin = testAdmin(user, fields.getfirst('administrator'), machine)
+        contact = testContact(user, fields.getfirst('contact'), machine)
+        hostname = testHostname(owner, fields.getfirst('hostname'), machine)
         name = testName(user, fields.getfirst('name'), machine)
         oldname = machine.name
@@ -644,8 +678,12 @@
             ctx.current.save(nic)
 
-        if owner is not None and owner != machine.owner:
+        if owner is not None:
             machine.owner = owner
-        if name is not None and name != machine.name:
+        if name is not None:
             machine.name = name
+        if admin is not None:
+            machine.administrator = admin
+        if contact is not None:
+            machine.contact = contact
             
         ctx.current.save(machine)
@@ -656,8 +694,7 @@
     for diskname in olddisk:
         remctl("web", "lvresize", oldname, diskname, str(olddisk[diskname]))
-    if name is not None and name != oldname:
+    if name is not None:
         for disk in machine.disks:
-            if oldname != name:
-                remctl("web", "lvrename", oldname, disk.guest_device_name, name)
+            remctl("web", "lvrename", oldname, disk.guest_device_name, name)
         remctl("web", "moveregister", oldname, name)
     d = dict(user=user,
@@ -681,10 +718,18 @@
 want an HVM virtualized machine.""",
                    cpu_weight="""Don't ask us!  We're as mystified as you are.""",
-                   owner="""The Owner must be the name of a locker that you are an AFS
-administrator of.  In particular, you or an AFS group you are a member
-of must have AFS rlidwka bits on the locker.  You can check see who
-administers the LOCKER locker using the command 'fs la /mit/LOCKER' on
-Athena.)""")
-    
+                   owner="""The owner field is used to determine <a href="help?subject=quotas">quotas</a>.  It must be the name
+of a locker that you are an AFS administrator of.  In particular, you
+or an AFS group you are a member of must have AFS rlidwka bits on the
+locker.  You can check see who administers the LOCKER locker using the
+command 'fs la /mit/LOCKER' on Athena.)  See also <a href="help?subject=administrator">administrator</a>.""",
+                   administrator="""The administrator field determines who can access the console and power on and off the machine.  This can be either a user or a moira group.""",
+                   quotas="""Quotas are determined on a per-locker basis.  Each 
+quota may have a maximum of 512 megabytes of active ram, 50 gigabytes of disk, and 4 active machines."""
+
+                   )
+    
+    if not subjects:
+        subjects = sorted(mapping.keys())
+        
     d = dict(user=user,
              simple=simple,
@@ -715,4 +760,5 @@
     display_fields = [('name', 'Name'),
                       ('owner', 'Owner'),
+                      ('administrator', 'Administrator'),
                       ('contact', 'Contact'),
                       ('type', 'Type'),
@@ -736,4 +782,5 @@
     machine_info['type'] = machine.type.hvm and 'HVM' or 'ParaVM'
     machine_info['owner'] = machine.owner
+    machine_info['administrator'] = machine.administrator
     machine_info['contact'] = machine.contact
 
@@ -817,7 +864,7 @@
         output = fun(u, fields)
         print 'Content-Type: text/html\n'
-        sys.stderr.seek(0)
-        e = sys.stderr.read()
         sys.stderr=sys.stdout
+        errio.seek(0)
+        e = errio.read()
         if e:
             output = str(output)
@@ -826,20 +873,20 @@
     except CodeError, err:
         print 'Content-Type: text/html\n'
-        sys.stderr.seek(0)
-        e = sys.stderr.read()
         sys.stderr=sys.stdout
+        errio.seek(0)
+        e = errio.read()
         print error(operation, u, fields, err, e)
     except InvalidInput, err:
         print 'Content-Type: text/html\n'
-        sys.stderr.seek(0)
-        e = sys.stderr.read()
         sys.stderr=sys.stdout
+        errio.seek(0)
+        e = errio.read()
         print invalidInput(operation, u, fields, err, e)
     except:
         print 'Content-Type: text/plain\n'
-        sys.stderr.seek(0)
-        e = sys.stderr.read()
+        sys.stderr=sys.stdout
+        errio.seek(0)
+        e = errio.read()
         print e
         print '----'
-        sys.stderr = sys.stdout
         raise
