--- /dev/null
+// SPDX-License-Identifier: GPL-2.1+
+/*
+ * Copyright (C) 2021 Sean Anderson <seanga2@gmail.com>
+ * Copyright (C) 2011-2021 Free Software Foundation, Inc.
+ *
+ * These tests adapted from glibc's string/test-strncat.c
+ */
+
+#include <common.h>
+#include <test/lib.h>
+#include <test/test.h>
+#include <test/ut.h>
+
+#define BUF_SIZE 4096
+char buf1[BUF_SIZE], buf2[BUF_SIZE];
+
+static int do_test_strlcat(struct unit_test_state *uts, int line, size_t align1,
+ size_t align2, size_t len1, size_t len2, size_t n)
+{
+ char *s1, *s2;
+ size_t i, len, expected, actual;
+
+ align1 &= 7;
+ if (align1 + len1 >= BUF_SIZE)
+ return 0;
+ if (align1 + n > BUF_SIZE)
+ return 0;
+
+ align2 &= 7;
+ if (align2 + len1 + len2 >= BUF_SIZE)
+ return 0;
+ if (align2 + len1 + n > BUF_SIZE)
+ return 0;
+
+ s1 = buf1 + align1;
+ s2 = buf2 + align2;
+
+ for (i = 0; i < len1 - 1; i++)
+ s1[i] = 32 + 23 * i % (127 - 32);
+ s1[len1 - 1] = '\0';
+
+ for (i = 0; i < len2 - 1; i++)
+ s2[i] = 32 + 23 * i % (127 - 32);
+ s2[len2 - 1] = '\0';
+
+ expected = len2 < n ? min(len1 + len2 - 1, n) : n;
+ actual = strlcat(s2, s1, n);
+ if (expected != actual) {
+ ut_failf(uts, __FILE__, line, __func__,
+ "strlcat(s2, s1, 2) == len2 < n ? min(len1 + len2, n) : n",
+ "Expected %#lx (%ld), got %#lx (%ld)",
+ expected, expected, actual, actual);
+ return CMD_RET_FAILURE;
+ }
+
+ len = min3(len1, n - len2, (size_t)0);
+ if (memcmp(s2 + len2, s1, len)) {
+ ut_failf(uts, __FILE__, line, __func__,
+ "s2 + len1 == s1",
+ "Expected \"%.*s\", got \"%.*s\"",
+ (int)len, s1, (int)len, s2 + len2);
+ return CMD_RET_FAILURE;
+ }
+
+ i = min(n, len1 + len2 - 1) - 1;
+ if (len2 < n && s2[i] != '\0') {
+ ut_failf(uts, __FILE__, line, __func__,
+ "n < len1 && s2[len2 + n] == '\\0'",
+ "Expected s2[%ld] = '\\0', got %d ('%c')",
+ i, s2[i], s2[i]);
+ return CMD_RET_FAILURE;
+ }
+
+ return 0;
+}
+
+#define test_strlcat(align1, align2, len1, len2, n) do { \
+ int ret = do_test_strlcat(uts, __LINE__, align1, align2, len1, len2, \
+ n); \
+ if (ret) \
+ return ret; \
+} while (0)
+
+static int lib_test_strlcat(struct unit_test_state *uts)
+{
+ size_t i, n;
+
+ test_strlcat(0, 2, 2, 2, SIZE_MAX);
+ test_strlcat(0, 0, 4, 4, SIZE_MAX);
+ test_strlcat(4, 0, 4, 4, SIZE_MAX);
+ test_strlcat(0, 0, 8, 8, SIZE_MAX);
+ test_strlcat(0, 8, 8, 8, SIZE_MAX);
+
+ for (i = 1; i < 8; i++) {
+ test_strlcat(0, 0, 8 << i, 8 << i, SIZE_MAX);
+ test_strlcat(8 - i, 2 * i, 8 << i, 8 << i, SIZE_MAX);
+ test_strlcat(0, 0, 8 << i, 2 << i, SIZE_MAX);
+ test_strlcat(8 - i, 2 * i, 8 << i, 2 << i, SIZE_MAX);
+
+ test_strlcat(i, 2 * i, 8 << i, 1, SIZE_MAX);
+ test_strlcat(2 * i, i, 8 << i, 1, SIZE_MAX);
+ test_strlcat(i, i, 8 << i, 10, SIZE_MAX);
+ }
+
+ for (n = 2; n <= 2048; n *= 4) {
+ test_strlcat(0, 2, 2, 2, n);
+ test_strlcat(0, 0, 4, 4, n);
+ test_strlcat(4, 0, 4, 4, n);
+ test_strlcat(0, 0, 8, 8, n);
+ test_strlcat(0, 8, 8, 8, n);
+
+ for (i = 1; i < 8; i++) {
+ test_strlcat(0, 0, 8 << i, 8 << i, n);
+ test_strlcat(8 - i, 2 * i, 8 << i, 8 << i, n);
+ test_strlcat(0, 0, 8 << i, 2 << i, n);
+ test_strlcat(8 - i, 2 * i, 8 << i, 2 << i, n);
+
+ test_strlcat(i, 2 * i, 8 << i, 1, n);
+ test_strlcat(2 * i, i, 8 << i, 1, n);
+ test_strlcat(i, i, 8 << i, 10, n);
+ }
+ }
+
+ return 0;
+}
+LIB_TEST(lib_test_strlcat, 0);