1 files changed, 448 insertions, 0 deletions
diff --git a/hicn-light/src/hicn/processor/fib.c b/hicn-light/src/hicn/processor/fib.c
new file mode 100644
index 000000000..e7a680f9c
--- /dev/null
+++ b/hicn-light/src/hicn/processor/fib.c
@@ -0,0 +1,448 @@
+/*
+ * Copyright (c) 2017-2019 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.
+ */
+
+#include <src/hicn/config.h>
+#include <stdio.h>
+
+#include <hicn/processor/fib.h>
+
+#include <parc/algol/parc_Memory.h>
+#include <parc/algol/parc_Network.h>
+
+#include <parc/assert/parc_Assert.h>
+
+#define NULL_POS 128
+#define MSB_POS 127
+
+struct node;
+typedef struct node FibNode;
+
+struct node {
+  FibNode *left;
+  FibNode *right;
+  FibEntry *entry;
+  unsigned pos;
+};
+
+struct fib {
+  FibNode *root;
+  unsigned size;
+};
+
+// =====================================================
+// Public API
+
+FibNode *_createNode(FibNode *left, FibNode *right, FibEntry *entry,
+                     unsigned pos) {
+  FibNode *n = parcMemory_AllocateAndClear(sizeof(FibNode));
+  parcAssertNotNull(n, "parcMemory_AllocateAndClear(%zu) returned NULL",
+                    sizeof(FibNode));
+
+  n->left = left;
+  n->right = right;
+  n->entry = entry;
+  n->pos = pos;
+
+  return n;
+}
+
+FIB *fib_Create() {
+  FIB *hicnFib = parcMemory_AllocateAndClear(sizeof(FIB));
+  parcAssertNotNull(hicnFib, "parcMemory_AllocateAndClear(%zu) returned NULL",
+                    sizeof(FIB));
+
+  hicnFib->root =
+      _createNode(NULL, NULL, NULL,
+                  NULL_POS);  // the pos will decrease going down in the trie
+  hicnFib->root->left = hicnFib->root;
+  hicnFib->root->right = hicnFib->root;
+
+  hicnFib->size = 0;
+
+  return hicnFib;
+}
+
+void _destroyNode(FibNode *n) {
+  fibEntry_Release(&n->entry);
+  parcMemory_Deallocate((void **)&n);
+  n = NULL;
+}
+
+void _destroyFib(FIB *fib) {
+  // XXX
+  // to be done
+  return;
+}
+
+void fib_Destroy(FIB **fibPtr) {
+  parcAssertNotNull(fibPtr, "Parameter must be non-null double pointer");
+  parcAssertNotNull(*fibPtr, "Parameter must dereference to non-null pointer");
+
+  FIB *fib = *fibPtr;
+
+  _destroyFib(fib);
+  parcMemory_Deallocate((void **)&fib);
+  *fibPtr = NULL;
+}
+
+void fib_Add(FIB *fib, FibEntry *entry) {
+  parcAssertNotNull(fib, "Parameter must be non-null");
+  parcAssertNotNull(entry, "Parameter must be non-null");
+
+  NameBitvector *name = name_GetContentName(fibEntry_GetPrefix(entry));
+
+  // search the name
+  FibNode *prev = fib->root;
+  FibNode *curr;
+
+  if (nameBitvector_testBit(name, MSB_POS)) {
+    curr = fib->root->right;
+  } else {
+    curr = fib->root->left;
+  }
+
+  while (prev->pos > curr->pos) {
+    prev = curr;
+    if (nameBitvector_testBit(name, curr->pos)) {
+      curr = curr->right;
+    } else {
+      curr = curr->left;
+    }
+  }
+
+  if (curr->entry != NULL &&
+      nameBitvector_Equals(
+          name, name_GetContentName(fibEntry_GetPrefix(curr->entry)))) {
+    // there is already an entry with this name
+    // do nothing. Before call ADD we should check
+    // if the node exists, and, in that case update it
+    return;
+  }
+
+  // if the name is not in the FIB search for the first different bit between
+  // the new name to add and the node found in the trie
+  uint8_t pos = MSB_POS;
+  if (curr->entry != NULL)
+    pos = nameBitvector_firstDiff(
+        name, name_GetContentName(fibEntry_GetPrefix(curr->entry)));
+
+  // reset pointer and search the insertion point
+  prev = fib->root;
+  if (nameBitvector_testBit(name, MSB_POS))
+    curr = fib->root->right;
+  else
+    curr = fib->root->left;
+
+  while (prev->pos > curr->pos && curr->pos > pos) {
+    prev = curr;
+    if (nameBitvector_testBit(name, curr->pos)) {
+      curr = curr->right;
+    } else {
+      curr = curr->left;
+    }
+  }
+
+  // insert the node
+  fib->size++;
+  FibNode *n = _createNode(NULL, NULL, entry, pos);
+
+  if (nameBitvector_testBit(name, pos)) {
+    n->left = curr;
+    n->right = n;
+  } else {
+    n->left = n;
+    n->right = curr;
+  }
+
+  uint8_t new_pos = prev->pos;
+  if (new_pos == NULL_POS) new_pos = MSB_POS;
+
+  if (nameBitvector_testBit(name, new_pos)) {
+    prev->right = n;
+  } else {
+    prev->left = n;
+  }
+}
+
+FibEntry *fib_Contains(const FIB *fib, const Name *prefix) {
+  parcAssertNotNull(fib, "Parameter must be non-null");
+  parcAssertNotNull(prefix, "Parameter must be non-null");
+
+  NameBitvector *name = name_GetContentName(prefix);
+
+  // this is the same as the first part of the add function
+  // we cannnot call this function inside the add because
+  // we need the pointer prev and curr for the insertion
+
+  FibNode *prev = fib->root;
+  FibNode *curr;
+
+  if (nameBitvector_testBit(name, MSB_POS))
+    curr = fib->root->right;
+  else
+    curr = fib->root->left;
+
+  while (prev->pos > curr->pos) {
+    prev = curr;
+
+    if (nameBitvector_testBit(name, curr->pos)) {
+      curr = curr->right;
+    } else {
+      curr = curr->left;
+    }
+  }
+
+  if (curr->entry != NULL &&
+      nameBitvector_Equals(
+          name, name_GetContentName(fibEntry_GetPrefix(curr->entry)))) {
+    return curr->entry;
+  } else {
+    return NULL;
+  }
+}
+
+void _removeNode(FIB *fib, const Name *prefix) {
+  parcAssertNotNull(fib, "Parameter must be non-null");
+  parcAssertNotNull(prefix, "Parameter must be non-null");
+
+  FibNode *grand = NULL;  // grandparent
+  FibNode *prev =
+      fib->root;  // parent: it will points to curr of the next hop in the trie
+  FibNode *curr;  // current node: the node to remove
+
+  NameBitvector *name = name_GetContentName(prefix);
+
+  if (nameBitvector_testBit(name, MSB_POS)) {
+    curr = fib->root->right;
+  } else {
+    curr = fib->root->left;
+  }
+
+  // in the first loop we always search the node to remove
+  while (prev->pos > curr->pos) {
+    grand = prev;
+    prev = curr;
+
+    if (nameBitvector_testBit(name, curr->pos)) {
+      curr = curr->right;
+    } else {
+      curr = curr->left;
+    }
+  }
+
+  if (!nameBitvector_Equals(
+          name, name_GetContentName(fibEntry_GetPrefix(curr->entry)))) {
+    // the node does not exists
+    return;
+  }
+
+  // search for the real parent of curr (*tmpPrev)
+  // prev points to curr or next node in the trie
+  // this is because of the loopback links
+
+  FibNode *tmpPrev = fib->root;
+  FibNode *tmpCurr;
+
+  if (nameBitvector_testBit(name, MSB_POS)) {
+    tmpCurr = fib->root->right;
+  } else {
+    tmpCurr = fib->root->left;
+  }
+
+  // here we compare pointer so we are sure to stop at the right potion
+  while (tmpCurr != curr) {
+    tmpPrev = tmpCurr;
+
+    if (nameBitvector_testBit(name, tmpCurr->pos)) {
+      tmpCurr = tmpCurr->right;
+    } else {
+      tmpCurr = tmpCurr->left;
+    }
+  }
+
+  // now curr is the node to remove and tmpPrev is the real parent of curr
+
+  if (curr == prev) {
+    // this is the case where curr is a leaf node
+    FibNode *next;  // child of curr (the loopback)
+
+    if (nameBitvector_testBit(name, curr->pos)) {
+      next = curr->left;
+    } else {
+      next = curr->right;
+    }
+
+    if (nameBitvector_testBit(name, tmpPrev->pos)) {
+      tmpPrev->right = next;
+    } else {
+      tmpPrev->left = next;
+    }
+
+  } else {
+    // curr is an internal node
+    FibNode *next;  // child of prev (loopback)
+
+    if (nameBitvector_testBit(name, prev->pos)) {
+      next = prev->left;
+    } else {
+      next = prev->right;
+    }
+
+    if (nameBitvector_testBit(name, grand->pos)) {
+      grand->right = next;
+    } else {
+      grand->left = next;
+    }
+
+    if (nameBitvector_testBit(name, tmpPrev->pos)) {
+      tmpPrev->right = prev;
+    } else {
+      tmpPrev->left = prev;
+    }
+
+    prev->left = curr->left;
+    prev->right = curr->right;
+    prev->pos = curr->pos;
+  }
+
+  fib->size--;
+  _destroyNode(curr);
+}
+
+void fib_Remove(FIB *fib, const Name *name, unsigned connId) {
+  parcAssertNotNull(fib, "Parameter must be non-null");
+  parcAssertNotNull(name, "Parameter must be non-null");
+
+  FibEntry *entry = fib_Contains(fib, name);
+
+  if (entry == NULL) {
+    return;
+  }
+
+  fibEntry_RemoveNexthopByConnectionId(entry, connId);
+  if (fibEntry_NexthopCount(entry) == 0) {
+    _removeNode(fib, name);
+  }
+}
+
+void _removeConnectionId(FibNode *n, unsigned pos, unsigned connectionId,
+                         FibEntryList *list) {
+  if (n->pos < pos) {
+    fibEntry_RemoveNexthopByConnectionId(n->entry, connectionId);
+    if (fibEntry_NexthopCount(n->entry) == 0) {
+      fibEntryList_Append(list, n->entry);
+    }
+    _removeConnectionId(n->left, n->pos, connectionId, list);
+    _removeConnectionId(n->right, n->pos, connectionId, list);
+  }
+}
+
+void fib_RemoveConnectionId(FIB *fib, unsigned connectionId) {
+  parcAssertNotNull(fib, "Parameter must be non-null");
+
+  // 1 - we vist the tree to remove the connection id
+  // 2 - during the visit we collect the fib entry with 0 nexthop
+  // 3 - after the visit we remove this entries
+
+  FibEntryList *list = fibEntryList_Create();
+
+  _removeConnectionId(fib->root->left, fib->root->pos, connectionId, list);
+  _removeConnectionId(fib->root->right, fib->root->pos, connectionId, list);
+
+  for (int i = 0; i < fibEntryList_Length(list); i++) {
+    _removeNode(fib, fibEntry_GetPrefix(fibEntryList_Get(list, i)));
+  }
+
+  fibEntryList_Destroy(&list);
+}
+
+size_t fib_Length(const FIB *fib) {
+  parcAssertNotNull(fib, "Parameter must be non-null");
+  return fib->size;
+}
+
+FibEntry *fib_Match(const FIB *fib, const Message *interestMessage) {
+  parcAssertNotNull(fib, "Parameter must be non-null");
+  parcAssertNotNull(interestMessage, "Parameter must be non-null");
+
+  NameBitvector *name = name_GetContentName(message_GetName(interestMessage));
+
+  FibNode *prev = fib->root;
+  FibNode *curr;
+
+  FibNode *match = NULL;
+  unsigned len = 0;
+
+  if (nameBitvector_testBit(name, MSB_POS))
+    curr = fib->root->right;
+  else
+    curr = fib->root->left;
+
+  while (prev->pos > curr->pos) {
+    prev = curr;
+
+    if (curr->entry != NULL) {
+      if (nameBitvector_StartsWith(
+              name, name_GetContentName(fibEntry_GetPrefix(curr->entry))) &&
+          nameBitvector_GetLength(
+              name_GetContentName(fibEntry_GetPrefix(curr->entry))) > len) {
+        match = curr;
+        len = nameBitvector_GetLength(
+            name_GetContentName(fibEntry_GetPrefix(curr->entry)));
+      }
+    }
+
+    if (nameBitvector_testBit(name, curr->pos))
+      curr = curr->right;
+    else
+      curr = curr->left;
+  }
+
+  if (curr->entry != NULL) {
+    if (nameBitvector_StartsWith(
+            name, name_GetContentName(fibEntry_GetPrefix(curr->entry))) &&
+        nameBitvector_GetLength(
+            name_GetContentName(fibEntry_GetPrefix(curr->entry))) > len) {
+      match = curr;
+      len = nameBitvector_GetLength(
+          name_GetContentName(fibEntry_GetPrefix(curr->entry)));
+    }
+  }
+
+  if (match != NULL && match->entry != NULL) {
+    return match->entry;
+  } else {
+    return NULL;
+  }
+}
+
+void _collectFibEntries(FibNode *n, int pos, FibEntryList *list) {
+  if (n->pos < (unsigned)pos) {
+    fibEntryList_Append(list, n->entry);
+    _collectFibEntries(n->left, n->pos, list);
+    _collectFibEntries(n->right, n->pos, list);
+  }
+}
+
+FibEntryList *fib_GetEntries(const FIB *fib) {
+  parcAssertNotNull(fib, "Parameter must be non-null");
+
+  FibEntryList *list = fibEntryList_Create();
+
+  _collectFibEntries(fib->root->left, fib->root->pos, list);
+  _collectFibEntries(fib->root->right, fib->root->pos, list);
+
+  return list;
+}