util.is_ipv4: realize that 0 is a valid number in a ipv4 address.

Due to bug in function "cloudinit.util.is_ipv4" an IPv4 address with zero (0)
at any component wasn't evaluated as IPv4 address.

E.g.: having local datasource with 192.168.0.1 in meta-data/local-hostname. The
correct behaviour would be to generate ip-192-168-0-1 hostname. With this bug,
the hostname (with IPv4) was considered as FQDN (no IPv4 inside) and just first
component (supposed to be hostname there) was taken. It generated hostname
"192".

Fixes for SmartOS datasource

1. fixed conflation of user-data and cloud-init user-data. Cloud-init
   user-data is now namespaced as 'cloud-init:user-data'.
2. user-scripts (not user-data) are now fetched from the meta-data service
   each boot and executed as in the scripts directory
3. datacenter name is now namespaced as sdc:datacenter
4. user-scripts will now have '#!/bin/bash' magically prepended
   if the 'file' thinks its plain text and it does not start with '#!'


read_file_or_url: raise UrlError with 404 on ENOENT

This makes it easier to call read_file_or_url and handle file or url
errors.  Now read_file_or_url will raise a UrlError in either case
on errors.

2 files changed, 2 insertions, 1 deletions

diff --git a/ChangeLog b/ChangeLog
index e547426e..63d1d62e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -22,6 +22,7 @@
  - configdrive: consider partitions as possible datasources if they have
    theh correct filesystem label. [Paul Querna]
  - initial freebsd support [Harm Weites]
+ - fix in is_ipv4 to accept IP addresses with a '0' in them.
 0.7.4:
  - fix issue mounting 'ephemeral0' if ephemeral0 was an alias for a
    partitioned block device with target filesystem on ephemeral0.1.
diff --git a/cloudinit/util.py b/cloudinit/util.py
index b3332acd..61bcdeb1 100644
--- a/cloudinit/util.py
+++ b/cloudinit/util.py
@@ -369,7 +369,7 @@ def is_ipv4(instr):
         return False
 
     try:
-        toks = [x for x in toks if (int(x) < 256 and int(x) > 0)]
+        toks = [x for x in toks if (int(x) < 256 and int(x) >= 0)]
     except:
         return False