Source / Include Folder (#88)

Moved Source Files Into `src` Folder

1 files changed, 156 insertions, 0 deletions

diff --git a/src/trie.h b/src/trie.h
new file mode 100644
index 0000000..2d29ac7
--- /dev/null
+++ b/src/trie.h
@@ -0,0 +1,156 @@
+/****************************************************************************
+ * bfs                                                                      *
+ * Copyright (C) 2019 Tavian Barnes <tavianator@tavianator.com>             *
+ *                                                                          *
+ * Permission to use, copy, modify, and/or distribute this software for any *
+ * purpose with or without fee is hereby granted.                           *
+ *                                                                          *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES *
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF         *
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR  *
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES   *
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN    *
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF  *
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.           *
+ ****************************************************************************/
+
+#ifndef BFS_TRIE_H
+#define BFS_TRIE_H
+
+#include <stddef.h>
+#include <stdint.h>
+
+/**
+ * A trie that holds a set of fixed- or variable-length strings.
+ */
+struct trie {
+	uintptr_t root;
+};
+
+/**
+ * A leaf of a trie.
+ */
+struct trie_leaf {
+	/**
+	 * An arbitrary value associated with this leaf.
+	 */
+	void *value;
+
+	/**
+	 * The length of the key in bytes.
+	 */
+	size_t length;
+
+	/**
+	 * The key itself, stored inline.
+	 */
+	char key[];
+};
+
+/**
+ * Initialize an empty trie.
+ */
+void trie_init(struct trie *trie);
+
+/**
+ * Get the first (lexicographically earliest) leaf in the trie.
+ *
+ * @param trie
+ *         The trie to search.
+ * @return
+ *         The first leaf, or NULL if the trie is empty.
+ */
+struct trie_leaf *trie_first_leaf(const struct trie *trie);
+
+/**
+ * Find the leaf for a string key.
+ *
+ * @param trie
+ *         The trie to search.
+ * @param key
+ *         The key to look up.
+ * @return
+ *         The found leaf, or NULL if the key is not present.
+ */
+struct trie_leaf *trie_find_str(const struct trie *trie, const char *key);
+
+/**
+ * Find the leaf for a fixed-size key.
+ *
+ * @param trie
+ *         The trie to search.
+ * @param key
+ *         The key to look up.
+ * @param length
+ *         The length of the key in bytes.
+ * @return
+ *         The found leaf, or NULL if the key is not present.
+ */
+struct trie_leaf *trie_find_mem(const struct trie *trie, const void *key, size_t length);
+
+/**
+ * Find the shortest leaf that starts with a given key.
+ *
+ * @param trie
+ *         The trie to search.
+ * @param key
+ *         The key to look up.
+ * @return
+ *         A leaf that starts with the given key, or NULL.
+ */
+struct trie_leaf *trie_find_postfix(const struct trie *trie, const char *key);
+
+/**
+ * Find the leaf that is the longest prefix of the given key.
+ *
+ * @param trie
+ *         The trie to search.
+ * @param key
+ *         The key to look up.
+ * @return
+ *         The longest prefix match for the given key, or NULL.
+ */
+struct trie_leaf *trie_find_prefix(const struct trie *trie, const char *key);
+
+/**
+ * Insert a string key into the trie.
+ *
+ * @param trie
+ *         The trie to modify.
+ * @param key
+ *         The key to insert.
+ * @return
+ *         The inserted leaf, or NULL on failure.
+ */
+struct trie_leaf *trie_insert_str(struct trie *trie, const char *key);
+
+/**
+ * Insert a fixed-size key into the trie.
+ *
+ * @param trie
+ *         The trie to modify.
+ * @param key
+ *         The key to insert.
+ * @param length
+ *         The length of the key in bytes.
+ * @return
+ *         The inserted leaf, or NULL on failure.
+ */
+struct trie_leaf *trie_insert_mem(struct trie *trie, const void *key, size_t length);
+
+/**
+ * Remove a leaf from a trie.
+ *
+ * @param trie
+ *         The trie to modify.
+ * @param leaf
+ *         The leaf to remove.
+ */
+void trie_remove(struct trie *trie, struct trie_leaf *leaf);
+
+/**
+ * Destroy a trie and its contents.
+ */
+void trie_destroy(struct trie *trie);
+
+#endif // BFS_TRIE_H