1 files changed, 390 insertions, 0 deletions
diff --git a/src/vnet/fib/fib_node_list.c b/src/vnet/fib/fib_node_list.c
new file mode 100644
index 00000000000..ceb951b466b
--- /dev/null
+++ b/src/vnet/fib/fib_node_list.c
@@ -0,0 +1,390 @@
+/*
+ * Copyright (c) 2016 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.
+ */
+/**
+ * @brief a hetrogeneous w.r.t. FIB node type, of FIB nodes.
+ * Since we cannot use C pointers, due to memeory reallocs, the next/prev
+ * are described as key:{type,index}.
+ */
+
+#include <vnet/fib/fib_node_list.h>
+
+/**
+ * @brief An element in the list
+ */
+typedef struct fib_node_list_elt_t_
+{
+    /**
+     * The index of the list this element is in
+     */
+    fib_node_list_t fnle_list;
+
+    /**
+     * The owner of this element
+     */
+    fib_node_ptr_t fnle_owner;
+
+    /**
+     * The next element in the list
+     */
+    u32 fnle_next;
+
+    /**
+     * The previous element in the list
+     */
+    u32 fnle_prev;
+} fib_node_list_elt_t;
+
+/**
+ * @brief A list of FIB nodes
+ */
+typedef struct fib_node_list_head_t_
+{
+    /**
+     * The head element
+     */
+    u32 fnlh_head;
+
+    /**
+     * Number of elements in the list
+     */
+    u32 fnlh_n_elts;
+} fib_node_list_head_t;
+
+/**
+ * Pools of list elements and heads
+ */
+static fib_node_list_elt_t *fib_node_list_elt_pool;
+static fib_node_list_head_t *fib_node_list_head_pool;
+
+static index_t
+fib_node_list_elt_get_index (fib_node_list_elt_t *elt)
+{
+    return (elt - fib_node_list_elt_pool);
+}
+
+static fib_node_list_elt_t *
+fib_node_list_elt_get (index_t fi)
+{
+    return (pool_elt_at_index(fib_node_list_elt_pool, fi));
+}
+
+static index_t
+fib_node_list_head_get_index (fib_node_list_head_t *head)
+{
+    return (head - fib_node_list_head_pool);
+}
+static fib_node_list_head_t *
+fib_node_list_head_get (fib_node_list_t fi)
+{
+    return (pool_elt_at_index(fib_node_list_head_pool, fi));
+}
+
+static fib_node_list_elt_t *
+fib_node_list_elt_create (fib_node_list_head_t *head,
+                          int id,
+                          fib_node_type_t type,
+                          fib_node_index_t index)
+{
+    fib_node_list_elt_t *elt;
+
+    pool_get(fib_node_list_elt_pool, elt);
+
+    elt->fnle_list = fib_node_list_head_get_index(head);
+    elt->fnle_owner.fnp_type  = type;
+    elt->fnle_owner.fnp_index = index;
+
+    elt->fnle_next = FIB_NODE_INDEX_INVALID;
+    elt->fnle_prev = FIB_NODE_INDEX_INVALID;
+
+    return (elt);
+}
+
+static void
+fib_node_list_head_init (fib_node_list_head_t *head)
+{
+    head->fnlh_n_elts = 0;
+    head->fnlh_head = FIB_NODE_INDEX_INVALID;
+}
+
+/**
+ * @brief Create a new node list.
+ */
+fib_node_list_t
+fib_node_list_create (void)
+{
+    fib_node_list_head_t *head;
+
+    pool_get(fib_node_list_head_pool, head);
+
+    fib_node_list_head_init(head);
+
+    return (fib_node_list_head_get_index(head));
+}
+
+void
+fib_node_list_destroy (fib_node_list_t *list)
+{
+    fib_node_list_head_t *head;
+
+    if (FIB_NODE_INDEX_INVALID == *list)
+        return;
+
+    head = fib_node_list_head_get(*list);
+    ASSERT(0 == head->fnlh_n_elts);
+
+    pool_put(fib_node_list_head_pool, head);
+    *list = FIB_NODE_INDEX_INVALID;
+}
+
+
+/**
+ * @brief Insert an element at the from of the list.
+ */
+u32
+fib_node_list_push_front (fib_node_list_t list,
+                          int owner_id,
+                          fib_node_type_t type,
+                          fib_node_index_t index)
+{
+    fib_node_list_elt_t *elt, *next;
+    fib_node_list_head_t *head;
+
+    head = fib_node_list_head_get(list);
+    elt = fib_node_list_elt_create(head, owner_id, type, index);
+
+    elt->fnle_prev = FIB_NODE_INDEX_INVALID;
+    elt->fnle_next = head->fnlh_head;
+
+    if (FIB_NODE_INDEX_INVALID != head->fnlh_head)
+    {
+        next = fib_node_list_elt_get(head->fnlh_head);
+        next->fnle_prev = fib_node_list_elt_get_index(elt);
+    }
+    head->fnlh_head = fib_node_list_elt_get_index(elt);
+
+    head->fnlh_n_elts++;
+
+    return (fib_node_list_elt_get_index(elt));
+}
+
+u32
+fib_node_list_push_back (fib_node_list_t list,
+                        int owner_id,
+                        fib_node_type_t type,
+                        fib_node_index_t index)
+{
+    ASSERT(0);
+    return (FIB_NODE_INDEX_INVALID);
+}
+
+static void
+fib_node_list_extract (fib_node_list_head_t *head,
+                       fib_node_list_elt_t *elt)
+{
+    fib_node_list_elt_t *next, *prev;
+
+    if (FIB_NODE_INDEX_INVALID != elt->fnle_next)
+    {
+        next = fib_node_list_elt_get(elt->fnle_next);
+        next->fnle_prev = elt->fnle_prev;
+    }
+
+    if (FIB_NODE_INDEX_INVALID != elt->fnle_prev)
+    {
+        prev = fib_node_list_elt_get(elt->fnle_prev);
+        prev->fnle_next = elt->fnle_next;
+    }
+    else
+    {
+        ASSERT (fib_node_list_elt_get_index(elt) == head->fnlh_head);
+        head->fnlh_head = elt->fnle_next;
+    }
+}
+
+static void
+fib_node_list_insert_after (fib_node_list_head_t *head,
+                            fib_node_list_elt_t *prev,
+                            fib_node_list_elt_t *elt)
+{
+    fib_node_list_elt_t *next;
+
+    elt->fnle_next = prev->fnle_next;
+    if (FIB_NODE_INDEX_INVALID != prev->fnle_next)
+    {
+        next = fib_node_list_elt_get(prev->fnle_next);
+        next->fnle_prev = fib_node_list_elt_get_index(elt);
+    }
+    prev->fnle_next = fib_node_list_elt_get_index(elt);
+    elt->fnle_prev = fib_node_list_elt_get_index(prev);
+}
+
+void
+fib_node_list_remove (fib_node_list_t list,
+                      u32 sibling)
+{
+    fib_node_list_head_t *head;
+    fib_node_list_elt_t *elt;
+
+    head = fib_node_list_head_get(list);
+    elt  = fib_node_list_elt_get(sibling);
+
+    fib_node_list_extract(head, elt);
+
+    head->fnlh_n_elts--;
+    pool_put(fib_node_list_elt_pool, elt);
+}
+
+void
+fib_node_list_elt_remove (u32 sibling)
+{
+    fib_node_list_elt_t *elt;
+
+    elt = fib_node_list_elt_get(sibling);
+
+    fib_node_list_remove(elt->fnle_list, sibling);
+}
+
+/**
+ * @brief Advance the sibling one step (toward the tail) in the list.
+ * return 0 if at the end of the list, 1 otherwise.
+ */
+int
+fib_node_list_advance (u32 sibling)
+{
+    fib_node_list_elt_t *elt, *next;
+    fib_node_list_head_t *head;
+
+    elt = fib_node_list_elt_get(sibling);
+    head = fib_node_list_head_get(elt->fnle_list);
+
+    if (FIB_NODE_INDEX_INVALID != elt->fnle_next)
+    {
+        /*
+         * not at the end of the list
+         */
+        next = fib_node_list_elt_get(elt->fnle_next);
+
+        fib_node_list_extract(head, elt);
+        fib_node_list_insert_after(head, next, elt);
+
+        return (1);
+    }
+    else
+    {
+        return (0);
+    }
+}
+
+int
+fib_node_list_elt_get_next (u32 sibling,
+                            fib_node_ptr_t *ptr)
+{
+    fib_node_list_elt_t *elt, *next;
+
+    elt = fib_node_list_elt_get(sibling);
+
+    if (FIB_NODE_INDEX_INVALID != elt->fnle_next)
+    {
+        next = fib_node_list_elt_get(elt->fnle_next);
+
+        *ptr = next->fnle_owner;
+        return (1);
+    }
+    else
+    {
+        ptr->fnp_index = FIB_NODE_INDEX_INVALID;
+        return (0);
+    }
+}
+
+u32
+fib_node_list_get_size (fib_node_list_t list)
+{
+    fib_node_list_head_t *head;
+
+    if (FIB_NODE_INDEX_INVALID == list)
+    {
+        return (0);
+    }
+
+    head = fib_node_list_head_get(list);
+
+    return (head->fnlh_n_elts);
+}
+
+int
+fib_node_list_get_front (fib_node_list_t list,
+                         fib_node_ptr_t *ptr)
+{
+    fib_node_list_head_t *head;
+    fib_node_list_elt_t *elt;
+
+
+    if (0 == fib_node_list_get_size(list))
+    {
+        ptr->fnp_index = FIB_NODE_INDEX_INVALID;
+        return (0);
+    }
+
+    head = fib_node_list_head_get(list);
+    elt = fib_node_list_elt_get(head->fnlh_head);
+    
+    *ptr = elt->fnle_owner;
+
+    return (1);
+}
+
+/**
+ * @brief Walk the list of node. This must be safe w.r.t. the removal
+ * of nodes during the walk.
+ */
+void
+fib_node_list_walk (fib_node_list_t list,
+                    fib_node_list_walk_cb_t fn,
+                    void *args)
+{
+    fib_node_list_elt_t *elt;
+    fib_node_list_head_t *head;
+    u32 sibling;
+
+    if (FIB_NODE_INDEX_INVALID == list)
+    {
+        return;
+    }
+
+    head = fib_node_list_head_get(list);
+    sibling = head->fnlh_head;
+
+    while (FIB_NODE_INDEX_INVALID != sibling)
+    {
+        elt = fib_node_list_elt_get(sibling);
+        sibling = elt->fnle_next;
+
+        fn(&elt->fnle_owner, args);
+    }
+}
+
+void
+fib_node_list_memory_show (void)
+{
+    fib_show_memory_usage("Node-list elements",
+			  pool_elts(fib_node_list_elt_pool),
+			  pool_len(fib_node_list_elt_pool),
+			  sizeof(fib_node_list_elt_t));
+    fib_show_memory_usage("Node-list heads",
+			  pool_elts(fib_node_list_head_pool),
+			  pool_len(fib_node_list_head_pool),
+			  sizeof(fib_node_list_head_t));
+}