1 files changed, 118 insertions, 0 deletions
diff --git a/hicn-light/src/hicn/core/subscription.c b/hicn-light/src/hicn/core/subscription.c
new file mode 100644
index 000000000..fb954a245
--- /dev/null
+++ b/hicn-light/src/hicn/core/subscription.c
@@ -0,0 +1,118 @@
+/*
+ * Copyright (c) 2021 Cisco and/or its affiliates.
+ */
+
+#include "subscription.h"
+#include <hicn/util/vector.h>
+#include <hicn/util/log.h>
+
+/*----------------------------------------------------------------------------*
+ * Topics and events
+ *----------------------------------------------------------------------------*/
+
+bool topics_contains(hc_topics_t topic_list, hc_topic_t topic) {
+  return ((topic_list) & (topic));
+}
+
+#define topic_is_set(topic_list, topic_index) \
+  ((topic_list) & (1 << (topic_index)))
+
+/*----------------------------------------------------------------------------*
+ * Subscriptions
+ *----------------------------------------------------------------------------*/
+
+struct subscription_table_s {
+  unsigned *table[TOPIC_N];
+};
+
+subscription_table_t *subscription_table_create() {
+  subscription_table_t *subscriptions = malloc(sizeof(subscription_table_t));
+  for (int i = 0; i < NUM_TOPICS; i++)
+    vector_init(subscriptions->table[i], 0, 0);
+
+  return subscriptions;
+}
+
+void subscription_table_free(subscription_table_t *subscriptions) {
+  for (int i = 0; i < NUM_TOPICS; i++) vector_free(subscriptions->table[i]);
+  free(subscriptions);
+}
+
+int subscription_table_add_topics_for_connection(
+    subscription_table_t *subscriptions, hc_topics_t topics,
+    unsigned connection_id) {
+  bool is_subscription_already_present = false;
+  for (int topic_index = 0; topic_index < NUM_TOPICS; topic_index++) {
+    if (topic_is_set(topics, topic_index)) {
+      int num_duplicates = vector_remove_unordered(
+          subscriptions->table[topic_index], connection_id);
+
+      int ret = vector_push(subscriptions->table[topic_index], connection_id);
+      if (ret < 0) {
+        ERROR("Unable to perform subscription for connection %d, topic %s",
+              connection_id, object_type_str(topic_index));
+        return -1;
+      }
+
+      if (num_duplicates > 0) {
+        DEBUG("Connection %d had already a subscription for topic %s",
+              connection_id, object_type_str(topic_index));
+        is_subscription_already_present = true;
+      }
+    }
+  }
+  return is_subscription_already_present ? -2 : 0;
+}
+
+int subscription_table_remove_topics_for_connection(
+    subscription_table_t *subscriptions, hc_topics_t topics,
+    unsigned connection_id) {
+  int num_subscriptions_removed = 0;
+  for (int topic_index = 0; topic_index < NUM_TOPICS; topic_index++) {
+    if (topic_is_set(topics, topic_index)) {
+      int num_duplicates = vector_remove_unordered(
+          subscriptions->table[topic_index], connection_id);
+      if (num_duplicates <= 0) {
+        continue;
+      }
+      num_subscriptions_removed++;
+    }
+  }
+  return num_subscriptions_removed;
+}
+
+hc_topics_t subscription_table_get_topics_for_connection(
+    subscription_table_t *subscriptions, unsigned connection_id) {
+  hc_topics_t topics = 0;
+  for (int topic_index = 0; topic_index < NUM_TOPICS; topic_index++) {
+    unsigned *conn_id;
+    bool found = false;
+    vector_foreach(subscriptions->table[topic_index], conn_id, {
+      if (*conn_id == connection_id) {
+        found = true;
+        break;
+      }
+    });
+    if (found) topics |= (1 << topic_index);
+  }
+  return topics;
+}
+
+unsigned *subscription_table_get_connections_for_topic(
+    subscription_table_t *subscriptions, hc_topic_t topic) {
+  int topic_index = object_from_topic(topic);
+  return subscriptions->table[topic_index];
+}
+
+void subscription_table_print(subscription_table_t *subscriptions) {
+  for (int topic_index = OBJECT_TYPE_UNDEFINED + 1; topic_index < NUM_TOPICS;
+       topic_index++) {
+    printf("topic %s (%lu subscription/s) from connection/s: [ ",
+           object_type_str(topic_index),
+           (unsigned long)vector_len(subscriptions->table[topic_index]));
+    unsigned *connection_id;
+    vector_foreach(subscriptions->table[topic_index], connection_id,
+                   { printf("%d ", *connection_id); });
+    printf("]\n");
+  }
+}