Beginnings of python rewrite

6 files changed, 155 insertions, 0 deletions

diff --git a/.gitignore b/.gitignore
index d926099..64ae595 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,3 @@
 .*.swp
+*.pyc
 coverage/
diff --git a/example.rb b/legacy/example.rb
index 182ae1d..182ae1d 100644
--- a/example.rb
+++ b/legacy/example.rb
diff --git a/state.rb b/legacy/state.rb
index 02c1bf3..02c1bf3 100644
--- a/state.rb
+++ b/legacy/state.rb
diff --git a/test.rb b/legacy/test.rb
index 87cb5bf..87cb5bf 100644
--- a/test.rb
+++ b/legacy/test.rb
diff --git a/test2.rb b/legacy/test2.rb
index 0a43d58..0a43d58 100644
--- a/test2.rb
+++ b/legacy/test2.rb
diff --git a/state.py b/state.py
new file mode 100644
index 0000000..594b32a
--- /dev/null
+++ b/state.py
@@ -0,0 +1,154 @@
+# 
+class Category:
+    def __init__(self, name, **args):
+        self.args = args
+        self.name = name
+
+    def equiv(self, other):
+        if self.name != other.name: return False
+        for key, value in self.args.iteritems():
+            if not other.args.has_key(key): return False
+            if value == None: continue
+            if other.args[key] == None: continue
+            if not other.args[key] == value: return False
+        return True
+    
+    def intersect(self, other):
+        if self.name != other.name: return None
+        args = {}
+        for key in list(set(self.args.keys() + other.args.keys())):
+            if not self.args.has_key(key):
+                args[key] = other.args[key]
+            elif not other.args.has_key(key):
+                args[key] = self.args[key]
+            elif self.args[key] == None:
+                args[key] = other.args[key]
+            elif other.args[key] == None:
+                args[key] = self.args[key]
+            elif self.args[key] != other.args[key]:
+                return None
+            else: # self.args[key] == other.args[key]
+                args[key] = self.args[key]
+        return Category(self.name, **args)
+
+    def __str__(self):
+        string = self.name + "("
+        had = False
+        for key, val in self.args.iteritems():
+            if had:
+                string += ", "
+            had = True
+            if val == None:
+                string += "%%%s" % key
+            else:
+                string += "%s: %s" % (key, val)
+        return string + ")"
+
+    def __repr__(self):
+        return self.__str__()
+
+    def __hash__(self):
+        return hash((self.argstup(), self.name))
+
+    def __eq__(self, other):
+        return self.name == other.name and self.argstup() == other.argstup()
+
+    def argstup(self):
+        retval = []
+        keys = self.args.keys()
+        keys.sort()
+        for key in keys:
+            retval.append((key, self.args[key]))
+        return tuple(retval)
+
+    def filter(self, other):
+        if not other.name == self.name:
+            raise TypeError, "States must be the same class"
+        args = {}
+        for key, value in other.args.iteritems():
+            if value != None or not self.args.has_key(key):
+                args[key] = value
+            else:
+                args[key] = self.args[key]
+        return Category(self.name, **args)
+
+    def fill(self, info):
+        args = {}
+        for key, value in self.args.iteritems():
+            if value != None or not info.has_key(key):
+                args[key] = value
+            else:
+                args[key] = info[key]
+        return Category(self.name, **args)
+
+    def is_finite(self):
+        return not None in self.args.values()
+
+class StateMachine:
+    def __init__(self):
+        self.holds = {}
+        self.deps = []
+
+    def assert_state(self, cat):
+        found = None
+        for dependency in self.get_applicable_deps(cat):
+            res = self.get_satisfied_states(cat, dependency)
+            if len(res) == 0:
+                return False
+            if found == None:
+                found = res
+            else:
+                found = self.intersect_list(found, res)
+        if found == None:
+            self.add_hold(cat)
+            return True
+        if len(found) == 0:
+            return False
+        for x in found:
+            self.add_hold(x)
+        return True
+
+    def intersect_list(self, cats1, cats2):
+        retval = set()
+        found = set()
+        for x in cats1:
+            for y in cats2:
+                if x == y: continue
+                inter = x.intersect(y)
+                if inter != None:
+                    retval.add(inter)
+                    found.add(x)
+                    found.add(y)
+        if len(found) == 0:
+            return cats1 & cats2
+        return (retval | ((cats1 & cats2) - found))
+
+    def add_hold(self, cat):
+        if self.holds.has_key(cat):
+            self.holds[cat] = self.holds[cat] + 1
+        else:
+            self.holds[cat] = 1
+
+    def get_satisfied_states(self, dependents, dependencies):
+        retval = []
+        for key, val in self.holds.iteritems():
+            if dependencies.equiv(key) and val > 0:
+                retval.append(dependents.fill(key.args))
+        return set(retval)
+
+    def get_applicable_deps(self, cat):
+        retval = []
+        for (x, y) in self.deps:
+            if x.equiv(cat):
+                retval.append(y.fill(cat.filter(x).args))
+        return retval
+
+if __name__ == "__main__":
+    sm = StateMachine()
+    sm.deps.append((Category("mounted", type="nfs"), Category("network_up")))
+    sm.deps.append((Category("mounted", uuid=None, devname=None, label=None), Category("found_disk", uuid=None, devname=None, label=None)))
+    sm.deps.append((Category("mounted", uuid=None, devname=None, label=None), Category("vol_conf", uuid=None, devname=None, label=None)))
+    sm.assert_state(Category("vol_conf", uuid=None, devname=None, label="myroot", type="ext3", mountpoint="/"))
+    sm.assert_state(Category("found_disk", uuid="d3adb3ef", devname="/dev/sda", label="myroot"))
+    sm.assert_state(Category("mounted", uuid=None, type="ext3", devname=None, label=None, mountpoint=None))
+    print sm.holds