--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/pvl/hosts/dhcp.py	Thu Feb 26 14:40:37 2015 +0200
@@ -0,0 +1,80 @@
+import pvl.dhcp.config
+import pvl.hosts.host
+
+class HostDHCPError(pvl.hosts.host.HostError):
+    pass
+
+def dhcp_host_options (host, ethernet):
+    """
+        Yield specific dhcp.conf host { ... } parameters for build_block()
+    """
+
+    yield 'option', 'host-name', host.name
+    yield 'hardware', 'ethernet', ethernet
+
+    if host.ip:
+        yield 'fixed-address', str(host.ip)
+      
+    if not host.boot:
+        next_server = filename = None
+    elif ':' in host.boot :
+        next_server, filename = host.boot.split(':', 1)
+    elif host.boot.startswith('/') :
+        next_server = None
+        filename = host.boot
+    elif host.boot.endswith(':') :
+        next_server = host.boot
+        filename = None
+    else :
+        raise HostError(host, "invalid boot={host.boot}".format(host=host))
+
+    if next_server:
+        yield 'next-server', next_server
+    
+    if filename:
+        yield 'filename', filename
+
+def dhcp_host (host):
+    """
+        Yield (block, items, **opts) tuples for pvl.dhcp.config.build_block().
+    """
+
+    if set(host.ethernet) == set([None]) :
+        host_fmt = "{host.name}"
+    elif host.ethernet :
+        host_fmt = "{host.name}-{index}"
+    else :
+        # nothing to be seen here
+        return
+ 
+    if host.owner :
+        comment = u"Owner: {host.owner}".format(host=host)
+    else:
+        comment = None
+
+    for index, ethernet in host.ethernet.iteritems() :
+        name = host_fmt.format(host=host, index=index)
+
+        yield ('host', name), list(dhcp_host_options(host, ethernet)), dict(comment=comment)
+    
+def apply_hosts_dhcp (options, hosts):
+    """
+        Generate dhcp.conf output lines for the set of hosts.
+
+        Verifies that there are no dupliate hosts.
+    """
+
+    blocks = { }
+
+    for host in hosts:
+        for block, items, opts in dhcp_host(host):
+            if block in blocks:
+                raise HostDHCPError(host, "dupliate host block {block}: {other}".format(block=block, other=blocks[block]))
+
+            blocks[block] = block
+
+            for line in pvl.dhcp.config.build_block(block, items, **opts):
+                yield line
+            
+            yield ''
+