1 files changed, 70 insertions, 0 deletions
diff --git a/src/hashtbl.h b/src/hashtbl.h
new file mode 100644
index 0000000..03eae65
--- /dev/null
+++ b/src/hashtbl.h
@@ -0,0 +1,70 @@
+/*
+ * Copyright (c) 2016-2021, OARC, Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * 3. Neither the name of the copyright holder nor the names of its
+ *    contributors may be used to endorse or promote products derived
+ *    from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef __dnscap_hashtbl_h
+#define __dnscap_hashtbl_h
+
+#define HASHTBL_EARGS -1
+#define HASHTBL_ENOMEM -2
+
+typedef struct hashitem hashitem;
+
+struct hashitem {
+    const void* key;
+    void*       data;
+    hashitem*   next;
+};
+
+typedef unsigned int (*hashkey_func)(const void* key);
+typedef int (*hashkeycmp_func)(const void* a, const void* b);
+typedef void (*hashfree_func)(void* data);
+
+typedef struct hashtbl hashtbl;
+struct hashtbl {
+    unsigned int modulus;
+    hashitem**   items;
+
+    hashkey_func    hasher;
+    hashkeycmp_func keycmp;
+    hashfree_func   datafree;
+};
+
+hashtbl* hash_create(unsigned int N, hashkey_func hasher, hashkeycmp_func cmp, hashfree_func datafree);
+int      hash_add(const void* key, void* data, hashtbl* tbl);
+void*    hash_find(const void* key, hashtbl* tbl);
+void     hash_remove(const void* key, hashtbl* tbl);
+void     hash_free(hashtbl* tbl);
+void     hash_destroy(hashtbl* tbl);
+
+#endif // __dnscap_hashtbl_h