1 files changed, 74 insertions, 0 deletions
diff --git a/hicn-light/src/hicn/core/pit.c b/hicn-light/src/hicn/core/pit.c
new file mode 100644
index 000000000..322e53674
--- /dev/null
+++ b/hicn-light/src/hicn/core/pit.c
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+/*
+ * Copyright (c) 2021 Cisco and/or its affiliates.
+ * 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.
+ */
+
+/**
+ * The pending interest table.
+ *
+ * Interest aggregation strategy:
+ * - The first Interest for a name is forwarded
+ * - A second Interest for a name from a different reverse path may be
+ * aggregated
+ * - A second Interest for a name from an existing Interest is forwarded
+ * - The Interest Lifetime is like a subscription time.  A reverse path entry is
+ * removed once the lifetime is exceeded.
+ * - Whan an Interest arrives or is aggregated, the Lifetime for that reverse
+ * hop is extended.  As a simplification, we only keep a single lifetime not per
+ * reverse hop.
+ *
+ */
+
+#include "pit.h"
+
+Ticks pit_calculate_lifetime(pit_t* pit, const msgbuf_t* msgbuf) {
+  uint64_t lifetime = msgbuf_get_lifetime(msgbuf);
+  if (lifetime == 0) lifetime = NSEC_TO_TICKS(DEFAULT_INTEREST_LIFETIME);
+
+  return ticks_now() + lifetime;
+}
+
+/* This is only used as a hint for first allocation, as the table is resizeable
+ */
+#define DEFAULT_PIT_SIZE 65535
+
+pit_t* _pit_create(size_t init_size, size_t max_size) {
+  pit_t* pit = malloc(sizeof(pit_t));
+  if (!pit) return NULL;
+
+  if (init_size == 0) init_size = DEFAULT_PIT_SIZE;
+
+  pit->max_size = max_size;
+  return pit;
+}
+
+void pit_free(pit_t* pit) {
+  assert(pit);
+  free(pit);
+}
+
+// void pit_print(const pit_t *pit) {
+//   const Name *k;
+//   unsigned v;
+//   pit_entry_t * entry;
+//   Ticks expire_ts;
+
+//   printf("*** PIT ***\n");
+//   kh_foreach(pit->index_by_name, k, v, {
+//     char *name_str = name_ToString(k);
+//     entry = pit_at(pit, v);
+//     expire_ts = pit_entry_get_expire_ts(entry);
+//     printf("%s\t\t\texpire=%lu\n", name_str, expire_ts);
+//     free(name_str);
+//   })
+// }