1 files changed, 63 insertions, 0 deletions
diff --git a/include/internal/uint_set.h b/include/internal/uint_set.h
new file mode 100644
index 000000000000..dcb29b33f3cc
--- /dev/null
+++ b/include/internal/uint_set.h
@@ -0,0 +1,63 @@
+/*
+ * Copyright 2022 The OpenSSL Project Authors. All Rights Reserved.
+ *
+ * Licensed under the Apache License 2.0 (the "License").  You may not use
+ * this file except in compliance with the License.  You can obtain a copy
+ * in the file LICENSE in the source distribution or at
+ * https://www.openssl.org/source/license.html
+ */
+#ifndef OSSL_UINT_SET_H
+# define OSSL_UINT_SET_H
+
+#include "openssl/params.h"
+#include "internal/list.h"
+
+/*
+ * uint64_t Integer Sets
+ * =====================
+ *
+ * Utilities for managing a logical set of unsigned 64-bit integers. The
+ * structure tracks each contiguous range of integers using one allocation and
+ * is thus optimised for cases where integers tend to appear consecutively.
+ * Queries are optimised under the assumption that they will generally be made
+ * on integers near the end of the set.
+ *
+ * Discussion of implementation details can be found in uint_set.c.
+ */
+typedef struct uint_range_st {
+    uint64_t    start, end;
+} UINT_RANGE;
+
+typedef struct uint_set_item_st UINT_SET_ITEM;
+struct uint_set_item_st {
+    OSSL_LIST_MEMBER(uint_set, UINT_SET_ITEM);
+    UINT_RANGE                  range;
+};
+
+DEFINE_LIST_OF(uint_set, UINT_SET_ITEM);
+
+typedef OSSL_LIST(uint_set) UINT_SET;
+
+void ossl_uint_set_init(UINT_SET *s);
+void ossl_uint_set_destroy(UINT_SET *s);
+
+/*
+ * Insert a range into a integer set. Returns 0 on allocation failure, in which
+ * case the integer set is in a valid but undefined state. Otherwise, returns 1.
+ * Ranges can overlap existing ranges without limitation. If a range is a subset
+ * of an existing range in the set, this is a no-op and returns 1.
+ */
+int ossl_uint_set_insert(UINT_SET *s, const UINT_RANGE *range);
+
+/*
+ * Remove a range from the set. Returns 0 on allocation failure, in which case
+ * the integer set is unchanged. Otherwise, returns 1. Ranges which are not
+ * already in the set can be removed without issue. If a passed range is not in
+ * the integer set at all, this is a no-op and returns 1.
+ */
+int ossl_uint_set_remove(UINT_SET *s, const UINT_RANGE *range);
+
+/* Returns 1 iff the given integer is in the integer set. */
+int ossl_uint_set_query(const UINT_SET *s, uint64_t v);
+
+#endif