From eab1349dff367e1aa546b08cbfc47bf9074dfcdb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marcus=20H=C3=BCwe?= <suse-tux@gmx.de>
Date: Tue, 29 Sep 2009 12:32:26 +0000
Subject: [PATCH] - util/debquery.py: implemented dpkg's version comparison
 algorithm - util/packagequery.py: added epoch() method

---
 osc/util/debquery.py     | 55 +++++++++++++++++++++++++++++++++++++---
 osc/util/packagequery.py |  3 +++
 2 files changed, 55 insertions(+), 3 deletions(-)

diff --git a/osc/util/debquery.py b/osc/util/debquery.py
index a201eb7c..2e5969ee 100644
--- a/osc/util/debquery.py
+++ b/osc/util/debquery.py
@@ -45,7 +45,13 @@ class DebQuery(packagequery.PackageQuery):
             self.fields['version'] = versrel[0]
             self.fields['release'] = versrel[1]
         else:
-            self.fields['release'] = None
+            self.fields['release'] = '0'
+        verep = self.fields['version'].split(':', 1)
+        if len(verep) == 2:
+            self.fields['epoch'] = verep[0]
+            self.fields['version'] = verep[1]
+        else:
+            self.fields['epoch'] = '0'
         self.fields['provides'] = [ i.strip() for i in re.split(',\s*', self.fields.get('provides', '')) if i ]
         self.fields['depends'] = [ i.strip() for i in re.split(',\s*', self.fields.get('depends', '')) if i ]
         self.fields['pre_depends'] = [ i.strip() for i in re.split(',\s*', self.fields.get('pre_depends', '')) if i ]
@@ -53,8 +59,14 @@ class DebQuery(packagequery.PackageQuery):
         self.fields['provides'].append('%s = %s' % (self.name(), '-'.join(versrel)))
 
     def vercmp(self, debq):
-        # XXX: just a dummy - the implementation will follow soon
-        return 0
+        res = cmp(int(self.epoch()), int(debq.epoch()))
+        if res != 0:
+            return res
+        res = DebQuery.debvercmp(self.version(), debq.version())
+        if res != 0:
+            return res
+        res = DebQuery.debvercmp(self.release(), debq.release())
+        return res
 
     def name(self):
         return self.fields['package']
@@ -65,6 +77,9 @@ class DebQuery(packagequery.PackageQuery):
     def release(self):
         return self.fields['release']
 
+    def epoch(self):
+        return self.fields['epoch']
+
     def arch(self):
         return self.fields['architecture']
 
@@ -88,6 +103,40 @@ class DebQuery(packagequery.PackageQuery):
         f.close()
         return debq
 
+    @staticmethod
+    def debvercmp(ver1, ver2):
+        """
+        implementation of dpkg's version comparison algorithm
+        """
+        # 32 is arbitrary - it is needed for the "longer digit string wins" handling
+        # (found this nice approach in Build/Deb.pm (build package))
+        ver1 = re.sub('(\d+)', lambda m: (32 * '0' + m.group(1))[-32:], ver1)
+        ver2 = re.sub('(\d+)', lambda m: (32 * '0' + m.group(1))[-32:], ver2)
+        vers = map(lambda x, y: (x or '', y or ''), ver1, ver2)
+        for v1, v2 in vers:
+            if v1 == v2:
+                continue
+            if (v1.isalpha() and v2.isalpha()) or (v1.isdigit() and v2.isdigit()):
+                res = cmp(v1, v2)
+                if res != 0:
+                    return res
+            else:
+                if v1 == '~' or not v1:
+                    return -1
+                elif v2 == '~' or not v2:
+                    return 1
+                ord1 = ord(v1)
+                if not (v1.isalpha() or v1.isdigit()):
+                    ord1 += 256
+                ord2 = ord(v2)
+                if not (v2.isalpha() or v2.isdigit()):
+                    ord2 += 256
+                if ord1 > ord2:
+                    return 1
+                else:
+                    return -1
+        return 0
+
 if __name__ == '__main__':
     import sys
     try:
diff --git a/osc/util/packagequery.py b/osc/util/packagequery.py
index 18d59377..3516b91c 100644
--- a/osc/util/packagequery.py
+++ b/osc/util/packagequery.py
@@ -18,6 +18,9 @@ class PackageQuery:
     def release(self):
         raise NotImplementedError
 
+    def epoch(self):
+        raise NotImplementedError
+
     def arch(self):
         raise NotImplementedError