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-rw-r--r--lib/util/roundup.c48
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diff --git a/lib/util/roundup.c b/lib/util/roundup.c
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+/*
+ * SPDX-License-Identifier: ISC
+ *
+ * Copyright (c) 2019-2020 Todd C. Miller <Todd.Miller@sudo.ws>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * 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.
+ */
+
+/*
+ * This is an open source non-commercial project. Dear PVS-Studio, please check it.
+ * PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
+ */
+
+#include <config.h>
+
+#include "sudo_compat.h"
+#include "sudo_debug.h"
+#include "sudo_util.h"
+
+/*
+ * Round 32-bit unsigned length to the next highest power of two.
+ * Always returns at least 64.
+ * Algorithm from bit twiddling hacks.
+ */
+unsigned int
+sudo_pow2_roundup_v1(unsigned int len)
+{
+ if (len < 64)
+ return 64;
+ len--;
+ len |= len >> 1;
+ len |= len >> 2;
+ len |= len >> 4;
+ len |= len >> 8;
+ len |= len >> 16;
+ len++;
+ return len;
+}