lib, ipcpd: Add hashtable and PDU Forwarding Function

This adds a hash table that takes 64-bit integers as key and uses
separate chaining on collision. It also adds the PDU Forwarding
Function, which the Flow Manager can use to lookup the fd towards the
next hop. Routing policies will add/update/remove entries in the PFF.

1 files changed, 55 insertions, 0 deletions

diff --git a/src/ipcpd/normal/pff.h b/src/ipcpd/normal/pff.h
new file mode 100644
index 00000000..b9ea1971
--- /dev/null
+++ b/src/ipcpd/normal/pff.h
@@ -0,0 +1,55 @@
+/*
+ * Ouroboros - Copyright (C) 2016
+ *
+ * PDU Forwarding Function
+ *
+ *    Sander Vrijders   <[email protected]>
+ *    Dimitri Staessens <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#ifndef OUROBOROS_IPCPD_NORMAL_PFF_H
+#define OUROBOROS_IPCPD_NORMAL_PFF_H
+
+#include <stdint.h>
+
+struct pff;
+
+/*
+ * PFF will take a type in the future,
+ * to allow different policies.
+ * Only 1 fd per next hop for now.
+ */
+struct pff * pff_create(void);
+
+int          pff_destroy(struct pff * instance);
+
+int          pff_add(struct pff * instance,
+                     uint64_t     addr,
+                     int          fd);
+
+int          pff_update(struct pff * instance,
+                        uint64_t     addr,
+                        int          fd);
+
+int          pff_remove(struct pff * instance,
+                        uint64_t     addr);
+
+/* Returns fd towards next hop */
+int          pff_nhop(struct pff * instance,
+                      uint64_t     addr);
+
+#endif /* OUROBOROS_IPCPD_NORMAL_PFF_H */