copy version.py from pyutil

diff --git a/src/allmydata/util/version.py b/src/allmydata/util/version.py
new file mode 100644 (file)
index 0000000..d5cbb36
--- /dev/null
+++ b/src/allmydata/util/version.py
@@ -0,0 +1,129 @@
+# Copyright (c) 2004-2007 Bryce "Zooko" Wilcox-O'Hearn
+# mailto:zooko@zooko.com
+# http://zooko.com/repos/pyutil
+# Permission is hereby granted, free of charge, to any person obtaining a copy 
+# of this work to deal in this work without restriction (including the rights 
+# to use, modify, distribute, sublicense, and/or sell copies).
+
+"""
+extended version number class
+"""
+
+from distutils import version
+
+# End users see version strings like this:
+
+# "1.0.0"
+#  ^ ^ ^
+#  | | |
+#  | | '- micro version number
+#  | '- minor version number
+#  '- major version number
+
+# The first number is "major version number".  The second number is the "minor
+# version number" -- it gets bumped whenever we make a new release that adds or
+# changes functionality.  The third version is the "micro version number" -- it
+# gets bumped whenever we make a new release that doesn't add or change
+# functionality, but just fixes bugs (including performance issues).
+
+# Early-adopter end users see version strings like this:
+
+# "1.0.0a1"
+#  ^ ^ ^^^
+#  | | |||
+#  | | ||'- release number
+#  | | |'- alpha or beta (or none)
+#  | | '- micro version number
+#  | '- minor version number
+#  '- major version number
+
+# The optional "a" or "b" stands for "alpha release" or "beta release"
+# respectively.  The number after "a" or "b" gets bumped every time we
+# make a new alpha or beta release. This has the same form and the same
+# meaning as version numbers of releases of Python.
+
+# Developers see "full version strings", like this:
+
+# "1.0.0a1-55-UNSTABLE"
+#  ^ ^ ^^^  ^     ^
+#  | | |||  |     |
+#  | | |||  |     '- tags
+#  | | |||  '- nano version number
+#  | | ||'- release number
+#  | | |'- alpha or beta (or none)
+#  | | '- micro version number
+#  | '- minor version number
+#  '- major version number
+
+# The next number is the "nano version number".  It is meaningful only to
+# developers.  It gets bumped whenever a developer changes anything that another
+# developer might care about.
+
+# The last part is the "tags" separated by "_".  Standard tags are
+# "STABLE" and "UNSTABLE".
+
+class Tag(str):
+    def __cmp__(t1, t2):
+        if t1 == t2:
+            return 0
+        if t1 == "UNSTABLE" and t2 == "STABLE":
+            return 1
+        if t1 == "STABLE" and t2 == "UNSTABLE":
+            return -1
+        return -2 # who knows
+
+class Version:
+    def __init__(self, vstring=None):
+        if vstring:
+            self.parse(vstring)
+
+    def parse(self, vstring):
+        i = vstring.find('-')
+        if i:
+            svstring = vstring[:i]
+            estring = vstring[i+1:]
+        else:
+            svstring = vstring
+            estring = None
+
+        self.strictversion = version.StrictVersion(svstring)
+
+        if estring:
+            try:
+                (self.nanovernum, tags,) = estring.split('-')
+            except:
+                print estring
+                raise
+            self.tags = map(Tag, tags.split('_'))
+            self.tags.sort()
+
+        self.fullstr = '-'.join([str(self.strictversion), str(self.nanovernum), '_'.join(self.tags)])
+          
+    def tags(self):
+        return self.tags
+
+    def user_str(self):
+        return self.strictversion.__str__()
+
+    def full_str(self):
+        return self.fullstr
+
+    def __str__(self):
+        return self.full_str()
+
+    def __repr__(self):
+        return self.__str__()
+
+    def __cmp__ (self, other):
+        if isinstance(other, basestring):
+            other = Version(other)
+
+        res = cmp(self.strictversion, other.strictversion)
+        if res != 0:
+            return res
+
+        res = cmp(self.nanovernum, other.nanovernum)
+        if res != 0:
+            return res
+
+        return cmp(self.tags, other.tags)