--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/planemo/lib/python3.7/site-packages/rdflib/plugins/sleepycat.py	Fri Jul 31 00:32:28 2020 -0400
@@ -0,0 +1,605 @@
+from rdflib.store import Store, VALID_STORE, NO_STORE
+from rdflib.term import URIRef
+from rdflib.py3compat import b
+
+
+def bb(u):
+    return u.encode('utf-8')
+
+
+try:
+    from bsddb import db
+    has_bsddb = True
+except ImportError:
+    try:
+        from bsddb3 import db
+        has_bsddb = True
+    except ImportError:
+        has_bsddb = False
+from os import mkdir
+from os.path import exists, abspath
+from urllib.request import pathname2url
+from threading import Thread
+
+if has_bsddb:
+    # These are passed to bsddb when creating DBs
+
+    # passed to db.DBEnv.set_flags
+    ENVSETFLAGS = db.DB_CDB_ALLDB
+    # passed to db.DBEnv.open
+    ENVFLAGS = db.DB_INIT_MPOOL | db.DB_INIT_CDB | db.DB_THREAD
+    CACHESIZE = 1024 * 1024 * 50
+
+    # passed to db.DB.Open()
+    DBOPENFLAGS = db.DB_THREAD
+
+import logging
+logger = logging.getLogger(__name__)
+
+__all__ = ['Sleepycat']
+
+
+class Sleepycat(Store):
+    context_aware = True
+    formula_aware = True
+    transaction_aware = False
+    graph_aware = True
+    db_env = None
+
+    def __init__(self, configuration=None, identifier=None):
+        if not has_bsddb:
+            raise ImportError(
+                "Unable to import bsddb/bsddb3, store is unusable.")
+        self.__open = False
+        self.__identifier = identifier
+        super(Sleepycat, self).__init__(configuration)
+        self._loads = self.node_pickler.loads
+        self._dumps = self.node_pickler.dumps
+
+    def __get_identifier(self):
+        return self.__identifier
+    identifier = property(__get_identifier)
+
+    def _init_db_environment(self, homeDir, create=True):
+        if not exists(homeDir):
+            if create is True:
+                mkdir(homeDir)
+                      # TODO: implement create method and refactor this to it
+                self.create(homeDir)
+            else:
+                return NO_STORE
+        db_env = db.DBEnv()
+        db_env.set_cachesize(0, CACHESIZE)  # TODO
+        # db_env.set_lg_max(1024*1024)
+        db_env.set_flags(ENVSETFLAGS, 1)
+        db_env.open(homeDir, ENVFLAGS | db.DB_CREATE)
+        return db_env
+
+    def is_open(self):
+        return self.__open
+
+    def open(self, path, create=True):
+        if not has_bsddb:
+            return NO_STORE
+        homeDir = path
+
+        if self.__identifier is None:
+            self.__identifier = URIRef(pathname2url(abspath(homeDir)))
+
+        db_env = self._init_db_environment(homeDir, create)
+        if db_env == NO_STORE:
+            return NO_STORE
+        self.db_env = db_env
+        self.__open = True
+
+        dbname = None
+        dbtype = db.DB_BTREE
+        # auto-commit ensures that the open-call commits when transactions
+        # are enabled
+
+        dbopenflags = DBOPENFLAGS
+        if self.transaction_aware is True:
+            dbopenflags |= db.DB_AUTO_COMMIT
+
+        if create:
+            dbopenflags |= db.DB_CREATE
+
+        dbmode = 0o660
+        dbsetflags = 0
+
+        # create and open the DBs
+        self.__indicies = [None, ] * 3
+        self.__indicies_info = [None, ] * 3
+        for i in range(0, 3):
+            index_name = to_key_func(
+                i)((b("s"), b("p"), b("o")), b("c")).decode()
+            index = db.DB(db_env)
+            index.set_flags(dbsetflags)
+            index.open(index_name, dbname, dbtype, dbopenflags, dbmode)
+            self.__indicies[i] = index
+            self.__indicies_info[i] = (index, to_key_func(i), from_key_func(i))
+
+        lookup = {}
+        for i in range(0, 8):
+            results = []
+            for start in range(0, 3):
+                score = 1
+                len = 0
+                for j in range(start, start + 3):
+                    if i & (1 << (j % 3)):
+                        score = score << 1
+                        len += 1
+                    else:
+                        break
+                tie_break = 2 - start
+                results.append(((score, tie_break), start, len))
+
+            results.sort()
+            score, start, len = results[-1]
+
+            def get_prefix_func(start, end):
+                def get_prefix(triple, context):
+                    if context is None:
+                        yield ""
+                    else:
+                        yield context
+                    i = start
+                    while i < end:
+                        yield triple[i % 3]
+                        i += 1
+                    yield ""
+                return get_prefix
+
+            lookup[i] = (
+                self.__indicies[start],
+                get_prefix_func(start, start + len),
+                from_key_func(start),
+                results_from_key_func(start, self._from_string))
+
+        self.__lookup_dict = lookup
+
+        self.__contexts = db.DB(db_env)
+        self.__contexts.set_flags(dbsetflags)
+        self.__contexts.open("contexts", dbname, dbtype, dbopenflags, dbmode)
+
+        self.__namespace = db.DB(db_env)
+        self.__namespace.set_flags(dbsetflags)
+        self.__namespace.open("namespace", dbname, dbtype, dbopenflags, dbmode)
+
+        self.__prefix = db.DB(db_env)
+        self.__prefix.set_flags(dbsetflags)
+        self.__prefix.open("prefix", dbname, dbtype, dbopenflags, dbmode)
+
+        self.__k2i = db.DB(db_env)
+        self.__k2i.set_flags(dbsetflags)
+        self.__k2i.open("k2i", dbname, db.DB_HASH, dbopenflags, dbmode)
+
+        self.__i2k = db.DB(db_env)
+        self.__i2k.set_flags(dbsetflags)
+        self.__i2k.open("i2k", dbname, db.DB_RECNO, dbopenflags, dbmode)
+
+        self.__needs_sync = False
+        t = Thread(target=self.__sync_run)
+        t.setDaemon(True)
+        t.start()
+        self.__sync_thread = t
+        return VALID_STORE
+
+    def __sync_run(self):
+        from time import sleep, time
+        try:
+            min_seconds, max_seconds = 10, 300
+            while self.__open:
+                if self.__needs_sync:
+                    t0 = t1 = time()
+                    self.__needs_sync = False
+                    while self.__open:
+                        sleep(.1)
+                        if self.__needs_sync:
+                            t1 = time()
+                            self.__needs_sync = False
+                        if time() - t1 > min_seconds \
+                                or time() - t0 > max_seconds:
+                            self.__needs_sync = False
+                            logger.debug("sync")
+                            self.sync()
+                            break
+                else:
+                    sleep(1)
+        except Exception as e:
+            logger.exception(e)
+
+    def sync(self):
+        if self.__open:
+            for i in self.__indicies:
+                i.sync()
+            self.__contexts.sync()
+            self.__namespace.sync()
+            self.__prefix.sync()
+            self.__i2k.sync()
+            self.__k2i.sync()
+
+    def close(self, commit_pending_transaction=False):
+        self.__open = False
+        self.__sync_thread.join()
+        for i in self.__indicies:
+            i.close()
+        self.__contexts.close()
+        self.__namespace.close()
+        self.__prefix.close()
+        self.__i2k.close()
+        self.__k2i.close()
+        self.db_env.close()
+
+    def add(self, triple, context, quoted=False, txn=None):
+        """\
+        Add a triple to the store of triples.
+        """
+        (subject, predicate, object) = triple
+        assert self.__open, "The Store must be open."
+        assert context != self, "Can not add triple directly to store"
+        Store.add(self, (subject, predicate, object), context, quoted)
+
+        _to_string = self._to_string
+
+        s = _to_string(subject, txn=txn)
+        p = _to_string(predicate, txn=txn)
+        o = _to_string(object, txn=txn)
+        c = _to_string(context, txn=txn)
+
+        cspo, cpos, cosp = self.__indicies
+
+        value = cspo.get(bb("%s^%s^%s^%s^" % (c, s, p, o)), txn=txn)
+        if value is None:
+            self.__contexts.put(bb(c), "", txn=txn)
+
+            contexts_value = cspo.get(
+                bb("%s^%s^%s^%s^" % ("", s, p, o)), txn=txn) or b("")
+            contexts = set(contexts_value.split(b("^")))
+            contexts.add(bb(c))
+            contexts_value = b("^").join(contexts)
+            assert contexts_value is not None
+
+            cspo.put(bb("%s^%s^%s^%s^" % (c, s, p, o)), "", txn=txn)
+            cpos.put(bb("%s^%s^%s^%s^" % (c, p, o, s)), "", txn=txn)
+            cosp.put(bb("%s^%s^%s^%s^" % (c, o, s, p)), "", txn=txn)
+            if not quoted:
+                cspo.put(bb(
+                    "%s^%s^%s^%s^" % ("", s, p, o)), contexts_value, txn=txn)
+                cpos.put(bb(
+                    "%s^%s^%s^%s^" % ("", p, o, s)), contexts_value, txn=txn)
+                cosp.put(bb(
+                    "%s^%s^%s^%s^" % ("", o, s, p)), contexts_value, txn=txn)
+
+            self.__needs_sync = True
+
+    def __remove(self, xxx_todo_changeme, c, quoted=False, txn=None):
+        (s, p, o) = xxx_todo_changeme
+        cspo, cpos, cosp = self.__indicies
+        contexts_value = cspo.get(
+            b("^").join([b(""), s, p, o, b("")]), txn=txn) or b("")
+        contexts = set(contexts_value.split(b("^")))
+        contexts.discard(c)
+        contexts_value = b("^").join(contexts)
+        for i, _to_key, _from_key in self.__indicies_info:
+            i.delete(_to_key((s, p, o), c), txn=txn)
+        if not quoted:
+            if contexts_value:
+                for i, _to_key, _from_key in self.__indicies_info:
+                    i.put(_to_key((s, p, o), b("")), contexts_value, txn=txn)
+            else:
+                for i, _to_key, _from_key in self.__indicies_info:
+                    try:
+                        i.delete(_to_key((s, p, o), b("")), txn=txn)
+                    except db.DBNotFoundError:
+                        pass  # TODO: is it okay to ignore these?
+
+    def remove(self, xxx_todo_changeme1, context, txn=None):
+        (subject, predicate, object) = xxx_todo_changeme1
+        assert self.__open, "The Store must be open."
+        Store.remove(self, (subject, predicate, object), context)
+        _to_string = self._to_string
+
+        if context is not None:
+            if context == self:
+                context = None
+
+        if subject is not None \
+                and predicate is not None \
+                and object is not None \
+                and context is not None:
+            s = _to_string(subject, txn=txn)
+            p = _to_string(predicate, txn=txn)
+            o = _to_string(object, txn=txn)
+            c = _to_string(context, txn=txn)
+            value = self.__indicies[0].get(bb("%s^%s^%s^%s^" %
+                                           (c, s, p, o)), txn=txn)
+            if value is not None:
+                self.__remove((bb(s), bb(p), bb(o)), bb(c), txn=txn)
+                self.__needs_sync = True
+        else:
+            cspo, cpos, cosp = self.__indicies
+            index, prefix, from_key, results_from_key = self.__lookup(
+                (subject, predicate, object), context, txn=txn)
+
+            cursor = index.cursor(txn=txn)
+            try:
+                current = cursor.set_range(prefix)
+                needs_sync = True
+            except db.DBNotFoundError:
+                current = None
+                needs_sync = False
+            cursor.close()
+            while current:
+                key, value = current
+                cursor = index.cursor(txn=txn)
+                try:
+                    cursor.set_range(key)
+                    # Hack to stop 2to3 converting this to next(cursor)
+                    current = getattr(cursor, 'next')()
+                except db.DBNotFoundError:
+                    current = None
+                cursor.close()
+                if key.startswith(prefix):
+                    c, s, p, o = from_key(key)
+                    if context is None:
+                        contexts_value = index.get(key, txn=txn) or b("")
+                        # remove triple from all non quoted contexts
+                        contexts = set(contexts_value.split(b("^")))
+                        # and from the conjunctive index
+                        contexts.add(b(""))
+                        for c in contexts:
+                            for i, _to_key, _ in self.__indicies_info:
+                                i.delete(_to_key((s, p, o), c), txn=txn)
+                    else:
+                        self.__remove((s, p, o), c, txn=txn)
+                else:
+                    break
+
+            if context is not None:
+                if subject is None and predicate is None and object is None:
+                    # TODO: also if context becomes empty and not just on
+                    # remove((None, None, None), c)
+                    try:
+                        self.__contexts.delete(
+                            bb(_to_string(context, txn=txn)), txn=txn)
+                    except db.DBNotFoundError:
+                        pass
+
+            self.__needs_sync = needs_sync
+
+    def triples(self, xxx_todo_changeme2, context=None, txn=None):
+        """A generator over all the triples matching """
+        (subject, predicate, object) = xxx_todo_changeme2
+        assert self.__open, "The Store must be open."
+
+        if context is not None:
+            if context == self:
+                context = None
+
+        # _from_string = self._from_string ## UNUSED
+        index, prefix, from_key, results_from_key = self.__lookup(
+            (subject, predicate, object), context, txn=txn)
+
+        cursor = index.cursor(txn=txn)
+        try:
+            current = cursor.set_range(prefix)
+        except db.DBNotFoundError:
+            current = None
+        cursor.close()
+        while current:
+            key, value = current
+            cursor = index.cursor(txn=txn)
+            try:
+                cursor.set_range(key)
+                # Cheap hack so 2to3 doesn't convert to next(cursor)
+                current = getattr(cursor, 'next')()
+            except db.DBNotFoundError:
+                current = None
+            cursor.close()
+            if key and key.startswith(prefix):
+                contexts_value = index.get(key, txn=txn)
+                yield results_from_key(
+                    key, subject, predicate, object, contexts_value)
+            else:
+                break
+
+    def __len__(self, context=None):
+        assert self.__open, "The Store must be open."
+        if context is not None:
+            if context == self:
+                context = None
+
+        if context is None:
+            prefix = b("^")
+        else:
+            prefix = bb("%s^" % self._to_string(context))
+
+        index = self.__indicies[0]
+        cursor = index.cursor()
+        current = cursor.set_range(prefix)
+        count = 0
+        while current:
+            key, value = current
+            if key.startswith(prefix):
+                count += 1
+                # Hack to stop 2to3 converting this to next(cursor)
+                current = getattr(cursor, 'next')()
+            else:
+                break
+        cursor.close()
+        return count
+
+    def bind(self, prefix, namespace):
+        prefix = prefix.encode("utf-8")
+        namespace = namespace.encode("utf-8")
+        bound_prefix = self.__prefix.get(namespace)
+        if bound_prefix:
+            self.__namespace.delete(bound_prefix)
+        self.__prefix[namespace] = prefix
+        self.__namespace[prefix] = namespace
+
+    def namespace(self, prefix):
+        prefix = prefix.encode("utf-8")
+        ns = self.__namespace.get(prefix, None)
+        if ns is not None:
+            return URIRef(ns.decode('utf-8'))
+        return None
+
+    def prefix(self, namespace):
+        namespace = namespace.encode("utf-8")
+        prefix = self.__prefix.get(namespace, None)
+        if prefix is not None:
+            return prefix.decode('utf-8')
+        return None
+
+    def namespaces(self):
+        cursor = self.__namespace.cursor()
+        results = []
+        current = cursor.first()
+        while current:
+            prefix, namespace = current
+            results.append((prefix.decode('utf-8'), namespace.decode('utf-8')))
+            # Hack to stop 2to3 converting this to next(cursor)
+            current = getattr(cursor, 'next')()
+        cursor.close()
+        for prefix, namespace in results:
+            yield prefix, URIRef(namespace)
+
+    def contexts(self, triple=None):
+        _from_string = self._from_string
+        _to_string = self._to_string
+
+        if triple:
+            s, p, o = triple
+            s = _to_string(s)
+            p = _to_string(p)
+            o = _to_string(o)
+            contexts = self.__indicies[0].get(bb(
+                "%s^%s^%s^%s^" % ("", s, p, o)))
+            if contexts:
+                for c in contexts.split(b("^")):
+                    if c:
+                        yield _from_string(c)
+        else:
+            index = self.__contexts
+            cursor = index.cursor()
+            current = cursor.first()
+            cursor.close()
+            while current:
+                key, value = current
+                context = _from_string(key)
+                yield context
+                cursor = index.cursor()
+                try:
+                    cursor.set_range(key)
+                    # Hack to stop 2to3 converting this to next(cursor)
+                    current = getattr(cursor, 'next')()
+                except db.DBNotFoundError:
+                    current = None
+                cursor.close()
+
+    def add_graph(self, graph):
+        self.__contexts.put(bb(self._to_string(graph)), "")
+
+    def remove_graph(self, graph):
+        self.remove((None, None, None), graph)
+
+    def _from_string(self, i):
+        k = self.__i2k.get(int(i))
+        return self._loads(k)
+
+    def _to_string(self, term, txn=None):
+        k = self._dumps(term)
+        i = self.__k2i.get(k, txn=txn)
+        if i is None:
+            # weird behavoir from bsddb not taking a txn as a keyword argument
+            # for append
+            if self.transaction_aware:
+                i = "%s" % self.__i2k.append(k, txn)
+            else:
+                i = "%s" % self.__i2k.append(k)
+
+            self.__k2i.put(k, i, txn=txn)
+        else:
+            i = i.decode()
+        return i
+
+    def __lookup(self, xxx_todo_changeme3, context, txn=None):
+        (subject, predicate, object) = xxx_todo_changeme3
+        _to_string = self._to_string
+        if context is not None:
+            context = _to_string(context, txn=txn)
+        i = 0
+        if subject is not None:
+            i += 1
+            subject = _to_string(subject, txn=txn)
+        if predicate is not None:
+            i += 2
+            predicate = _to_string(predicate, txn=txn)
+        if object is not None:
+            i += 4
+            object = _to_string(object, txn=txn)
+        index, prefix_func, from_key, results_from_key = self.__lookup_dict[i]
+        # print (subject, predicate, object), context, prefix_func, index
+        # #DEBUG
+        prefix = bb(
+            "^".join(prefix_func((subject, predicate, object), context)))
+        return index, prefix, from_key, results_from_key
+
+
+def to_key_func(i):
+    def to_key(triple, context):
+        "Takes a string; returns key"
+        return b("^").join(
+            (context,
+             triple[i % 3],
+             triple[(i + 1) % 3],
+             triple[(i + 2) % 3], b("")))  # "" to tac on the trailing ^
+    return to_key
+
+
+def from_key_func(i):
+    def from_key(key):
+        "Takes a key; returns string"
+        parts = key.split(b("^"))
+        return \
+            parts[0], \
+            parts[(3 - i + 0) % 3 + 1], \
+            parts[(3 - i + 1) % 3 + 1], \
+            parts[(3 - i + 2) % 3 + 1]
+    return from_key
+
+
+def results_from_key_func(i, from_string):
+    def from_key(key, subject, predicate, object, contexts_value):
+        "Takes a key and subject, predicate, object; returns tuple for yield"
+        parts = key.split(b("^"))
+        if subject is None:
+            # TODO: i & 1: # dis assemble and/or measure to see which is faster
+            # subject is None or i & 1
+            s = from_string(parts[(3 - i + 0) % 3 + 1])
+        else:
+            s = subject
+        if predicate is None:  # i & 2:
+            p = from_string(parts[(3 - i + 1) % 3 + 1])
+        else:
+            p = predicate
+        if object is None:  # i & 4:
+            o = from_string(parts[(3 - i + 2) % 3 + 1])
+        else:
+            o = object
+        return (s, p, o), (
+            from_string(c) for c in contexts_value.split(b("^")) if c)
+    return from_key
+
+
+def readable_index(i):
+    s, p, o = "?" * 3
+    if i & 1:
+        s = "s"
+    if i & 2:
+        p = "p"
+    if i & 4:
+        o = "o"
+    return "%s,%s,%s" % (s, p, o)