+// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Graph data structure.
*
* --
* Copyright (C) 2016 Cumulus Networks, Inc.
- *
- * This file is part of GNU Zebra.
- *
- * GNU Zebra 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, or (at your option) any
- * later version.
- *
- * GNU Zebra 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 GNU Zebra; see the file COPYING. If not, write to the Free
- * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
- * 02111-1307, USA.
*/
#ifndef _ZEBRA_COMMAND_GRAPH_H
#define _ZEBRA_COMMAND_GRAPH_H
+#include <stdbool.h>
#include "vector.h"
+#include "buffer.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
-struct graph
-{
- vector nodes;
+struct graph {
+ vector nodes;
};
-struct graph_node
-{
- vector from; // nodes which have edges to this node
- vector to; // nodes which this node has edges to
+struct graph_node {
+ vector from; // nodes which have edges to this node
+ vector to; // nodes which this node has edges to
- void *data; // node data
- void (*del) (void *data); // deletion callback
+ void *data; // node data
+ void (*del)(void *data); // deletion callback
};
-struct graph *
-graph_new (void);
+struct graph *graph_new(void);
/**
* Creates a new node.
* @param[in] del data deletion callback
* @return the new node
*/
-struct graph_node *
-graph_new_node (struct graph *graph, void *data, void (*del) (void*));
+struct graph_node *graph_new_node(struct graph *graph, void *data,
+ void (*del)(void *));
/**
* Deletes a node.
* @param[in] graph the graph this node belongs to
* @param[out] node pointer to node to delete
*/
-void
-graph_delete_node (struct graph *graph, struct graph_node *node);
+void graph_delete_node(struct graph *graph, struct graph_node *node);
/**
* Makes a directed edge between two nodes.
* @param[in] to
* @return to
*/
-struct graph_node *
-graph_add_edge (struct graph_node *from, struct graph_node *to);
+struct graph_node *graph_add_edge(struct graph_node *from,
+ struct graph_node *to);
/**
* Removes a directed edge between two nodes.
* @param[in] from
* @param[in] to
*/
-void
-graph_remove_edge (struct graph_node *from, struct graph_node *to);
+void graph_remove_edge(struct graph_node *from, struct graph_node *to);
/**
* Deletes a graph.
*
* @param graph the graph to delete
*/
-void
-graph_delete_graph (struct graph *graph);
+void graph_delete_graph(struct graph *graph);
+
+/*
+ * Finds a node in the graph.
+ *
+ * @param[in] graph the graph to search in
+ * @param[in] data the data to key off
+ * @return the first graph node whose data pointer matches `data`
+ */
+struct graph_node *graph_find_node(struct graph *graph, void *data);
+
+
+/*
+ * Determines whether two nodes have a directed edge between them.
+ *
+ * @param from
+ * @param to
+ * @return whether there is a directed edge from `from` to `to`.
+ */
+bool graph_has_edge(struct graph_node *from, struct graph_node *to);
+
+/*
+ * Depth-first search.
+ *
+ * Performs a depth-first traversal of the given graph, visiting each node
+ * exactly once and calling the user-provided callback for each visit.
+ *
+ * @param graph the graph to operate on
+ * @param start the node to take as the root
+ * @param dfs_cb callback called for each node visited in the traversal
+ * @param arg argument to provide to dfs_cb
+ */
+void graph_dfs(struct graph *graph, struct graph_node *start,
+ void (*dfs_cb)(struct graph_node *, void *), void *arg);
+
+#ifndef BUILDING_CLIPPY
+/*
+ * Clippy relies on a small subset of sources in lib/, but it cannot link
+ * libfrr since clippy itself is required to build libfrr. Instead it directly
+ * includes the sources it needs. One of these is the command graph
+ * implementation, which wraps this graph implementation. Since we need to use
+ * the buffer.[ch] sources here, which indirectly rely on most of libfrr, we
+ * have to ignore them when compiling clippy to avoid build dependency issues.
+ *
+ * TODO: Fix clippy build.
+ */
+
+/*
+ * Default node printer for use with graph_dump_dot.
+ *
+ * @param gn the node to print
+ * @param buf the buffer to print into
+ */
+void graph_dump_dot_default_print_cb(struct graph_node *gn, struct buffer *buf);
+
+/*
+ * Prints a graph in the DOT language.
+ *
+ * The generated output is produced from a depth-first traversal of the graph.
+ *
+ * @param graph the graph to print
+ * @param start the node to take as the root
+ * @param pcb callback called for each node in the traversal that should
+ * print the node in the DOT language. Passing NULL for this argument
+ * will use the default printer. See graph_dump_dot_default_print_cb for
+ * an example.
+ * @return representation of graph in DOT language, allocated with MTYPE_TMP.
+ * Caller is responsible for freeing this string.
+ */
+char *graph_dump_dot(struct graph *graph, struct graph_node *start,
+ void (*pcb)(struct graph_node *, struct buffer *buf));
+
+#endif /* BUILDING_CLIPPY */
+
+#ifdef __cplusplus
+}
+#endif
#endif /* _ZEBRA_COMMAND_GRAPH_H */