switch to using hashlib.md5 or md5 (if python 2.4) instead of a os call

library/setup

@@ -33,6 +33,13 @@ import subprocess
 import traceback
 import syslog
 
+try:
+    import hashlib
+    HAVE_HASHLIB=True
+except ImportError:
+    import md5
+    HAVE_HASHLIB=False
+
 try:
     import selinux
     HAVE_SELINUX=True
@@ -311,9 +318,20 @@ def ansible_facts():
     get_service_facts(facts)
     return facts
 
-def md5_sum(f):
-    md5sum = os.popen("/usr/bin/md5sum %(file)s 2>/dev/null || /sbin/md5 -q %(file)s 2>/dev/null || /usr/bin/digest -a md5 -v %(file)s 2>/dev/null" % {"file": f}).read().split()[0]
-    return md5sum
+def local_md5(filename):
+     ''' compute local md5sum, return None if file is not present '''
+     if os.path.exists(filename):
+         md5val=None
+         if os.path.exists(filename):
+             if HAVE_HASHLIB:
+                 md5val=hashlib.md5(file(filename).read()).hexdigest()
+             else:
+                 md5val=md5.new(file(filename).read()).hexdigest()
+         return md5val
+     else:
+         return None
+
+# ===========================================
 
 # load config & template variables
 
@@ -351,7 +369,7 @@ md5sum = None
 if not os.path.exists(ansible_file):
     changed = True
 else:
-    md5sum = md5_sum(ansible_file)
+    md5sum = local_md5(ansible_file)
 
 # Get some basic facts in case facter or ohai are not installed
 for (k, v) in ansible_facts().items():
@@ -400,7 +418,7 @@ reformat = json.dumps(setup_options, sort_keys=True, indent=4)
 f.write(reformat)
 f.close()
 
-md5sum2 = md5_sum(ansible_file)
+md5sum2 = local_md5(ansible_file)
 
 if md5sum != md5sum2:
    changed = True