lib: Add support for sets of UUIDs.

Part of the uuidset implementation is taken from the OVN codebase where
it was added via commit 0e77b3bcbfe2 ("ovn-northd-ddlog: New
implementation of ovn-northd based on ddlog.").

We now extend that, adding a few helpers and tests.

Co-authored-by: Leonid Ryzhyk <lryzhyk@vmware.com>
Signed-off-by: Leonid Ryzhyk <lryzhyk@vmware.com>
Co-authored-by: Justin Pettit <jpettit@ovn.org>
Signed-off-by: Justin Pettit <jpettit@ovn.org>
Co-authored-by: Ben Pfaff <blp@ovn.org>
Signed-off-by: Ben Pfaff <blp@ovn.org>
Signed-off-by: Dumitru Ceara <dceara@redhat.com>
Reviewed-by: Ales Musil <amusil@redhat.com>
Signed-off-by: Ilya Maximets <i.maximets@ovn.org>

lib/automake.mk

@@ -386,6 +386,8 @@ lib_libopenvswitch_la_SOURCES = \
 	lib/util.h \
 	lib/uuid.c \
 	lib/uuid.h \
+	lib/uuidset.c \
+	lib/uuidset.h \
 	lib/valgrind.h \
 	lib/vconn-provider.h \
 	lib/vconn-stream.c \

lib/uuidset.c

@@ -0,0 +1,99 @@
+/*
+ * Copyright (c) 2020, 2022 VMware, Inc.
+ * Copyright (c) 2022 Red Hat, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <config.h>
+
+#include "lib/uuidset.h"
+#include "lib/util.h"
+
+void
+uuidset_init(struct uuidset *set)
+{
+    hmap_init(&set->uuids);
+}
+
+void
+uuidset_destroy(struct uuidset *set)
+{
+    if (set) {
+        uuidset_clear(set);
+        hmap_destroy(&set->uuids);
+    }
+}
+
+void uuidset_clear(struct uuidset *set)
+{
+    struct uuidset_node *node;
+
+    HMAP_FOR_EACH_SAFE (node, hmap_node, &set->uuids) {
+        uuidset_delete(set, node);
+    }
+}
+
+struct uuidset_node *
+uuidset_find(const struct uuidset *set, const struct uuid *uuid)
+{
+    struct uuidset_node *node;
+
+    HMAP_FOR_EACH_WITH_HASH (node, hmap_node, uuid_hash(uuid), &set->uuids) {
+        if (uuid_equals(uuid, &node->uuid)) {
+            return node;
+        }
+    }
+
+    return NULL;
+}
+
+bool
+uuidset_find_and_delete(struct uuidset *set, const struct uuid *uuid)
+{
+    struct uuidset_node *node = uuidset_find(set, uuid);
+    if (node) {
+        uuidset_delete(set, node);
+    }
+    return !!node;
+}
+
+void
+uuidset_insert(struct uuidset *set, const struct uuid *uuid)
+{
+    if (!uuidset_find(set, uuid)) {
+        struct uuidset_node *node = xmalloc(sizeof *node);
+        node->uuid = *uuid;
+        hmap_insert(&set->uuids, &node->hmap_node, uuid_hash(&node->uuid));
+    }
+}
+
+void
+uuidset_delete(struct uuidset *set, struct uuidset_node *node)
+{
+    hmap_remove(&set->uuids, &node->hmap_node);
+    free(node);
+}
+
+struct uuid*
+uuidset_array(const struct uuidset *set)
+{
+    struct uuid *array = xmalloc(uuidset_count(set) * sizeof *array);
+    struct uuidset_node *node;
+    size_t i = 0;
+
+    UUIDSET_FOR_EACH (node, set) {
+        array[i++] = node->uuid;
+    }
+    return array;
+}

lib/uuidset.h

@@ -0,0 +1,71 @@
+/*
+ * Copyright (c) 2020, 2022 VMware, Inc.
+ * Copyright (c) 2022 Red Hat, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef OVN_UUIDSET_H
+#define OVN_UUIDSET_H 1
+
+#include "lib/uuid.h"
+#include "openvswitch/hmap.h"
+
+/* A node within a set of uuids. */
+struct uuidset_node {
+    struct hmap_node hmap_node;
+    struct uuid uuid;
+};
+
+/* A set of UUIDs. */
+struct uuidset {
+    struct hmap uuids;
+};
+
+#define UUIDSET_INITIALIZER(UUIDSET) \
+    { .uuids = HMAP_INITIALIZER(&(UUIDSET)->uuids) }
+
+#define UUIDSET_FOR_EACH(NODE, SET) \
+    HMAP_FOR_EACH (NODE, hmap_node, &(SET)->uuids)
+
+#define UUIDSET_FOR_EACH_SAFE(NODE, SET) \
+    HMAP_FOR_EACH_SAFE (NODE, hmap_node, &(SET)->uuids)
+
+void uuidset_init(struct uuidset *);
+void uuidset_destroy(struct uuidset *);
+void uuidset_clear(struct uuidset *);
+struct uuidset_node *uuidset_find(const struct uuidset *, const struct uuid *);
+bool uuidset_find_and_delete(struct uuidset *, const struct uuid *);
+void uuidset_insert(struct uuidset *, const struct uuid *);
+void uuidset_delete(struct uuidset *, struct uuidset_node *);
+struct uuid *uuidset_array(const struct uuidset *);
+
+static inline bool
+uuidset_is_empty(const struct uuidset *set)
+{
+    return hmap_is_empty(&set->uuids);
+}
+
+static inline size_t
+uuidset_count(const struct uuidset *set)
+{
+    return hmap_count(&set->uuids);
+}
+
+static inline bool
+uuidset_contains(const struct uuidset *set, const struct uuid *uuid)
+{
+    return !!uuidset_find(set, uuid);
+}
+
+#endif /* lib/uuidset.h */

tests/.gitignore

@@ -67,6 +67,7 @@
 /test-unix-socket
 /test-util
 /test-uuid
+/test-uuidset
 /test-vconn
 /testsuite
 /testsuite.dir/

tests/automake.mk

@@ -483,6 +483,7 @@ tests_ovstest_SOURCES = \
 	tests/test-unixctl.c \
 	tests/test-util.c \
 	tests/test-uuid.c \
+	tests/test-uuidset.c \
 	tests/test-bitmap.c \
 	tests/test-vconn.c \
 	tests/test-aa.c \

tests/library.at

@@ -274,3 +274,7 @@ AT_CLEANUP
 AT_SETUP([id-fpool module])
 AT_CHECK([ovstest test-id-fpool check], [0], [])
 AT_CLEANUP
+
+AT_SETUP([uuidset module])
+AT_CHECK([ovstest test-uuidset], [0], [], [ignore])
+AT_CLEANUP

tests/test-uuidset.c

@@ -0,0 +1,72 @@
+/*
+ * Copyright (c) 2022 Red Hat, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <config.h>
+
+#include "lib/util.h"
+#include "lib/uuidset.h"
+
+#include "ovstest.h"
+
+static void
+test_uuidset_main(int argc OVS_UNUSED, char *argv[] OVS_UNUSED)
+{
+    struct uuidset set = UUIDSET_INITIALIZER(&set);
+    struct uuid uuids[2];
+
+    for (size_t i = 0; i < ARRAY_SIZE(uuids); i++) {
+        uuid_generate(&uuids[i]);
+    }
+
+    ovs_assert(uuidset_is_empty(&set));
+
+    for (size_t i = 0; i < ARRAY_SIZE(uuids); i++) {
+        struct uuid *u = &uuids[i];
+
+        if (i == 0) {
+            ovs_assert(uuidset_is_empty(&set));
+        } else {
+            ovs_assert(!uuidset_is_empty(&set));
+        }
+        ovs_assert(uuidset_count(&set) == i);
+        ovs_assert(!uuidset_contains(&set, u));
+        ovs_assert(!uuidset_find_and_delete(&set, u));
+
+        /* Insert twice to check set property. */
+        uuidset_insert(&set, u);
+        uuidset_insert(&set, u);
+        ovs_assert(uuidset_count(&set) == i + 1);
+
+        struct uuidset_node *n = uuidset_find(&set, u);
+        ovs_assert(n);
+        uuidset_delete(&set, n);
+        ovs_assert(uuidset_count(&set) == i);
+        ovs_assert(!uuidset_contains(&set, u));
+
+        uuidset_insert(&set, u);
+        ovs_assert(uuidset_count(&set) == i + 1);
+        ovs_assert(uuidset_contains(&set, u));
+        ovs_assert(uuidset_find_and_delete(&set, u));
+        ovs_assert(uuidset_count(&set) == i);
+        ovs_assert(!uuidset_contains(&set, u));
+
+        uuidset_insert(&set, u);
+    }
+
+    uuidset_destroy(&set);
+}
+
+OVSTEST_REGISTER("test-uuidset", test_uuidset_main);