vppinfra: deprecate vppinfra/graph.[ch]

Type: refactor
Change-Id: Iba0466b60354955ba73f851435a7127435b7066d
Signed-off-by: Damjan Marion <damarion@cisco.com>

2 files changed, 309 insertions, 0 deletions

diff --git a/extras/deprecated/vppinfra/graph.c b/extras/deprecated/vppinfra/graph.c
new file mode 100644
index 00000000000..4c92f8ef45f
--- /dev/null
+++ b/extras/deprecated/vppinfra/graph.c
@@ -0,0 +1,182 @@
+/*
+ * Copyright (c) 2015 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 <vppinfra/graph.h>
+
+/* Set link distance, creating link if not found. */
+u32
+graph_set_link (graph_t * g, u32 src, u32 dst, u32 distance)
+{
+  graph_node_t *src_node, *dst_node;
+  graph_link_t *l;
+  u32 old_distance;
+
+  /* The following validate will not work if src or dst are on the
+     pool free list. */
+  if (src < vec_len (g->nodes))
+    ASSERT (!pool_is_free_index (g->nodes, src));
+  if (dst < vec_len (g->nodes))
+    ASSERT (!pool_is_free_index (g->nodes, dst));
+
+  /* Make new (empty) nodes to make src and dst valid. */
+  pool_validate_index (g->nodes, clib_max (src, dst));
+
+  src_node = pool_elt_at_index (g->nodes, src);
+  dst_node = pool_elt_at_index (g->nodes, dst);
+
+  l = graph_dir_get_link_to_node (&src_node->next, dst);
+  if (l)
+    {
+      old_distance = l->distance;
+      l->distance = distance;
+
+      l = graph_dir_get_link_to_node (&dst_node->prev, src);
+      l->distance = distance;
+    }
+  else
+    {
+      uword li_next, li_prev;
+
+      old_distance = ~0;
+
+      li_next = graph_dir_add_link (&src_node->next, dst, distance);
+      li_prev = graph_dir_add_link (&dst_node->prev, src, distance);
+
+      l = vec_elt_at_index (src_node->next.links, li_next);
+      l->link_to_self_index = li_prev;
+
+      l = vec_elt_at_index (dst_node->prev.links, li_prev);
+      l->link_to_self_index = li_next;
+    }
+
+  return old_distance;
+}
+
+void
+graph_del_link (graph_t * g, u32 src, u32 dst)
+{
+  graph_node_t *src_node, *dst_node;
+
+  src_node = pool_elt_at_index (g->nodes, src);
+  dst_node = pool_elt_at_index (g->nodes, dst);
+
+  graph_dir_del_link (&src_node->next, dst);
+  graph_dir_del_link (&dst_node->next, src);
+}
+
+/* Delete source node and all links from other nodes from/to source. */
+uword
+graph_del_node (graph_t * g, u32 src)
+{
+  graph_node_t *src_node, *n;
+  uword index;
+  graph_link_t *l;
+
+  src_node = pool_elt_at_index (g->nodes, src);
+
+  vec_foreach (l, src_node->next.links)
+  {
+    n = pool_elt_at_index (g->nodes, l->node_index);
+    graph_dir_del_link (&n->prev, src);
+  }
+
+  vec_foreach (l, src_node->prev.links)
+  {
+    n = pool_elt_at_index (g->nodes, l->node_index);
+    graph_dir_del_link (&n->next, src);
+  }
+
+  graph_dir_free (&src_node->next);
+  graph_dir_free (&src_node->prev);
+
+  index = src_node - g->nodes;
+  pool_put (g->nodes, src_node);
+  clib_memset (src_node, ~0, sizeof (src_node[0]));
+
+  return index;
+}
+
+uword
+unformat_graph (unformat_input_t * input, va_list * args)
+{
+  graph_t *g = va_arg (*args, graph_t *);
+  typedef struct
+  {
+    u32 src, dst, distance;
+  } T;
+  T *links = 0, *l;
+  uword result;
+
+  while (1)
+    {
+      vec_add2 (links, l, 1);
+      if (!unformat (input, "%d%d%d", &l->src, &l->dst, &l->distance))
+	break;
+    }
+  _vec_len (links) -= 1;
+  result = vec_len (links) > 0;
+  vec_foreach (l, links)
+  {
+    graph_set_link (g, l->src, l->dst, l->distance);
+    graph_set_link (g, l->dst, l->src, l->distance);
+  }
+
+  vec_free (links);
+  return result;
+}
+
+u8 *
+format_graph_node (u8 * s, va_list * args)
+{
+  graph_t *g = va_arg (*args, graph_t *);
+  u32 node_index = va_arg (*args, u32);
+
+  if (g->format_node)
+    s = format (s, "%U", g->format_node, g, node_index);
+  else
+    s = format (s, "%d", node_index);
+
+  return s;
+}
+
+u8 *
+format_graph (u8 * s, va_list * args)
+{
+  graph_t *g = va_arg (*args, graph_t *);
+  graph_node_t *n;
+  graph_link_t *l;
+  u32 indent = format_get_indent (s);
+
+  s = format (s, "graph %d nodes", pool_elts (g->nodes));
+  /* *INDENT-OFF* */
+  pool_foreach (n, g->nodes)  {
+    s = format (s, "\n%U", format_white_space, indent + 2);
+    s = format (s, "%U -> ", format_graph_node, g, n - g->nodes);
+    vec_foreach (l, n->next.links)
+      s = format (s, "%U (%d), ",
+		  format_graph_node, g, l->node_index,
+		  l->distance);
+  }
+  /* *INDENT-ON* */
+
+  return s;
+}
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/extras/deprecated/vppinfra/graph.h b/extras/deprecated/vppinfra/graph.h
new file mode 100644
index 00000000000..1c26118f76c
--- /dev/null
+++ b/extras/deprecated/vppinfra/graph.h
@@ -0,0 +1,127 @@
+/*
+ * Copyright (c) 2015 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.
+ */
+#ifndef included_clib_graph_h
+#define included_clib_graph_h
+
+#include <vppinfra/format.h>
+#include <vppinfra/hash.h>
+#include <vppinfra/pool.h>
+
+/* Generic graphs. */
+typedef struct
+{
+  /* Next node along this link. */
+  u32 node_index;
+
+  /* Other direction link index to reach back to current node. */
+  u32 link_to_self_index;
+
+  /* Distance to next node. */
+  u32 distance;
+} graph_link_t;
+
+/* Direction on graph: either next or previous. */
+typedef struct
+{
+  /* Vector of links. */
+  graph_link_t *links;
+
+  /* Hash mapping node index to link which visits this node. */
+  uword *link_index_by_node_index;
+} graph_dir_t;
+
+always_inline void
+graph_dir_free (graph_dir_t * d)
+{
+  vec_free (d->links);
+  hash_free (d->link_index_by_node_index);
+}
+
+always_inline graph_link_t *
+graph_dir_get_link_to_node (graph_dir_t * d, u32 node_index)
+{
+  uword *p = hash_get (d->link_index_by_node_index, node_index);
+  return p ? vec_elt_at_index (d->links, p[0]) : 0;
+}
+
+always_inline uword
+graph_dir_add_link (graph_dir_t * d, u32 node_index, u32 distance)
+{
+  graph_link_t *l;
+  ASSERT (!graph_dir_get_link_to_node (d, node_index));
+  vec_add2 (d->links, l, 1);
+  l->node_index = node_index;
+  l->distance = distance;
+  hash_set (d->link_index_by_node_index, node_index, l - d->links);
+  return l - d->links;
+}
+
+always_inline void
+graph_dir_del_link (graph_dir_t * d, u32 node_index)
+{
+  graph_link_t *l = graph_dir_get_link_to_node (d, node_index);
+  uword li = l - d->links;
+  uword n_links = vec_len (d->links);
+
+  ASSERT (l != 0);
+  hash_unset (d->link_index_by_node_index, node_index);
+  n_links -= 1;
+  if (li < n_links)
+    d->links[li] = d->links[n_links];
+  _vec_len (d->links) = n_links;
+}
+
+typedef struct
+{
+  /* Nodes we are connected to plus distances. */
+  graph_dir_t next, prev;
+} graph_node_t;
+
+typedef struct
+{
+  /* Pool of nodes. */
+  graph_node_t *nodes;
+
+  void *opaque;
+
+  format_function_t *format_node;
+} graph_t;
+
+/* Set link distance, creating link if not found. */
+u32 graph_set_link (graph_t * g, u32 src, u32 dst, u32 distance);
+
+always_inline void
+graph_set_bidirectional_link (graph_t * g, u32 src, u32 dst, u32 distance)
+{
+  graph_set_link (g, src, dst, distance);
+  graph_set_link (g, dst, src, distance);
+}
+
+void graph_del_link (graph_t * g, u32 src, u32 dst);
+uword graph_del_node (graph_t * g, u32 src);
+
+unformat_function_t unformat_graph;
+format_function_t format_graph;
+format_function_t format_graph_node;
+
+#endif /* included_clib_graph_h */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */