This is similar to include/linux/hashtable.h, but the implementation
has been simplified.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
---
scripts/kconfig/hashtable.h | 48 +++++++++++++++++++++++++++++++++++++
1 file changed, 48 insertions(+)
create mode 100644 scripts/kconfig/hashtable.h
new file mode 100644
@@ -0,0 +1,48 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef HASHTABLE_H
+#define HASHTABLE_H
+
+#include "array_size.h"
+#include "list.h"
+
+#define HASH_SIZE(name) (ARRAY_SIZE(name))
+
+#define HASHTABLE_DECLARE(name, size) struct hlist_head name[size]
+
+#define HASHTABLE_DEFINE(name, size) \
+ HASHTABLE_DECLARE(name, size) = \
+ { [0 ... ((size) - 1)] = HLIST_HEAD_INIT }
+
+#define hash_head(table, key) (&(table)[(key) % HASH_SIZE(table)])
+
+/**
+ * hash_add - add an object to a hashtable
+ * @table: hashtable to add to
+ * @node: the &struct hlist_node of the object to be added
+ * @key: the key of the object to be added
+ */
+#define hash_add(table, node, key) \
+ hlist_add_head(node, hash_head(table, key))
+
+/**
+ * hash_for_each - iterate over a hashtable
+ * @table: hashtable to iterate
+ * @obj: the type * to use as a loop cursor for each entry
+ * @member: the name of the hlist_node within the struct
+ */
+#define hash_for_each(table, obj, member) \
+ for (int bkt = 0; bkt < HASH_SIZE(table); bkt++) \
+ hlist_for_each_entry(obj, &table[bkt], member)
+
+/**
+ * hash_for_each_possible - iterate over all possible objects hashing to the
+ * same bucket
+ * @table: hashtable to iterate
+ * @obj: the type * to use as a loop cursor for each entry
+ * @member: the name of the hlist_node within the struct
+ * @key: the key of the objects to iterate over
+ */
+#define hash_for_each_possible(table, obj, member, key) \
+ hlist_for_each_entry(obj, hash_head(table, key), member)
+
+#endif /* HASHTABLE_H */