Adding function compare_fqdn()

diff --git a/pp_lib/common.py b/pp_lib/common.py
index 22700e8cd294b2b7cb9091aaca8e3c4e68a403dd..cfcaa3e5524f1775e93e75b650209591c0415741 100644 (file)
--- a/pp_lib/common.py
+++ b/pp_lib/common.py
@@ -21,7 +21,7 @@ import six
 
 # Own modules
 
-__version__ = '0.4.2'
+__version__ = '0.5.1'
 
 LOG = logging.getLogger(__name__)
 
@@ -32,6 +32,9 @@ RE_TO_BOOL_TRUE = re.compile(PAT_TO_BOOL_TRUE)
 PAT_TO_BOOL_FALSE = locale.nl_langinfo(locale.NOEXPR)
 RE_TO_BOOL_FALSE = re.compile(PAT_TO_BOOL_FALSE)
 
+RE_DOT = re.compile(r'\.')
+RE_DOT_AT_END = re.compile(r'(\.)*$')
+
 
 # =============================================================================
 def pp(value, indent=4, width=99, depth=None):
@@ -286,6 +289,57 @@ def caller_search_path():
 
     return path_list
 
+# =============================================================================
+def compare_fqdn(x, y):
+
+    # First check for None values
+    if x is None and y is None:
+        return 0
+    if x is None:
+        return -1
+    if y is None:
+        return 1
+
+    xs = str(x).strip().lower()
+    ys = str(y).strip().lower()
+
+    if xs == '' and ys == '':
+        return 0
+    if xs == '':
+        return -1
+    if ys == '':
+        return 1
+
+    xs = RE_DOT_AT_END.sub('.', xs)
+    ys = RE_DOT_AT_END.sub('.', ys)
+
+    if xs == ys:
+        return 0
+
+    xa = RE_DOT.split(xs)
+    xa.reverse()
+    xa.pop(0)
+
+    ya = RE_DOT.split(ys)
+    ya.reverse()
+    ya.pop(0)
+
+    nr_tokens = min(len(xa), len(ya))
+    while nr_tokens > 0:
+        token_x = xa.pop(0)
+        token_y = ya.pop(0)
+        if token_x < token_y:
+            return -1
+        elif token_x > token_y:
+            return 1
+        nr_tokens -= 1
+
+    if len(xa):
+        return 1
+    if len(ya):
+        return -1
+
+    return 0
 
 # =============================================================================