tests: Add lib/memcpy-test test case

Signed-off-by: Jakub Czapiga <jacz@semihalf.com>
Change-Id: I00464ec2db23867712cd2efd7f6cad92e3ee361a
Reviewed-on: https://review.coreboot.org/c/coreboot/+/50799
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Fagerburg <pfagerburg@chromium.org>

tests/lib/memcpy-test.c

@@ -0,0 +1,196 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+/* Include memcpy() source code and alter its name to compare results with libc memcpy() */
+#define memcpy cb_memcpy
+#include "../lib/memcpy.c"
+#undef memcpy
+
+#include <stdlib.h>
+#include <tests/test.h>
+#include <commonlib/helpers.h>
+#include <types.h>
+
+#define MEMCPY_BUFFER_SZ (4 * KiB)
+
+/* Prototype of memcpy() from string.h was changed to cb_memcpy().
+   It has to be defined again. */
+void *memcpy(void *dest, const void *src, size_t n);
+
+struct test_memcpy_data {
+	u8 *buffer_from;
+	u8 *buffer_to;
+	u8 *helper_buffer;
+};
+
+int setup_test(void **state)
+{
+	struct test_memcpy_data *s = malloc(sizeof(struct test_memcpy_data));
+
+	if (!s)
+		return -1;
+
+	s->buffer_from = malloc(MEMCPY_BUFFER_SZ);
+	s->buffer_to = malloc(MEMCPY_BUFFER_SZ);
+	s->helper_buffer = malloc(MEMCPY_BUFFER_SZ);
+
+	if (!s->buffer_from || !s->buffer_to || !s->helper_buffer) {
+		free(s->buffer_from);
+		free(s->buffer_to);
+		free(s->helper_buffer);
+		free(s);
+		return -1;
+	}
+
+	/* Fill buffers with different values (other than zero) to make them distinguishable.
+	   The helper buffer is often used as a backup of destination buffer so it has the
+	   same value. */
+	memset(s->buffer_from, 0xAB, MEMCPY_BUFFER_SZ);
+	memset(s->buffer_to, 0xBC, MEMCPY_BUFFER_SZ);
+	memset(s->helper_buffer, 0xBC, MEMCPY_BUFFER_SZ);
+
+	*state = s;
+
+	return 0;
+}
+
+int teardown_test(void **state)
+{
+	struct test_memcpy_data *s = *state;
+
+	free(s->buffer_from);
+	free(s->buffer_to);
+	free(s->helper_buffer);
+	free(s);
+
+	return 0;
+}
+
+/* Fill buffer with values from provided range [start; end] in circular way. */
+static void fill_buffer_data_range(u8 *buffer, size_t sz, u8 start_value, u8 end_value)
+{
+	for (size_t i = 0; i < sz; ++i)
+		buffer[i] = (start_value + i) % (end_value - start_value + 1);
+}
+
+static void test_memcpy_full_buffer_copy(void **state)
+{
+	struct test_memcpy_data *s = *state;
+	void *res_cb;
+
+	fill_buffer_data_range(s->buffer_from, MEMCPY_BUFFER_SZ, 0, 255);
+
+	res_cb = cb_memcpy(s->buffer_to, s->buffer_from, MEMCPY_BUFFER_SZ);
+
+	assert_ptr_equal(s->buffer_to, res_cb);
+	assert_memory_equal(s->buffer_from, s->buffer_to, MEMCPY_BUFFER_SZ);
+}
+
+static void test_memcpy_zero_size(void **state)
+{
+	struct test_memcpy_data *s = *state;
+	void *res_cb;
+
+	fill_buffer_data_range(s->buffer_from, MEMCPY_BUFFER_SZ, 'A', 'Z');
+
+	/* Expect no change in destination buffer. */
+	res_cb = cb_memcpy(s->buffer_to, s->buffer_from, 0);
+	assert_ptr_equal(s->buffer_to, res_cb);
+	assert_memory_equal(s->buffer_to, s->helper_buffer, MEMCPY_BUFFER_SZ);
+}
+
+static void test_memcpy_buffer_part(void **state)
+{
+	struct test_memcpy_data *s = *state;
+	void *res_cb;
+	const size_t offset = MEMCPY_BUFFER_SZ / 4;
+	const size_t sz = MEMCPY_BUFFER_SZ / 2;
+
+	/* Self-test for correct data ranges */
+	assert_true(offset + sz <= MEMCPY_BUFFER_SZ);
+
+	fill_buffer_data_range(s->buffer_from, MEMCPY_BUFFER_SZ, '0', '9');
+
+	/* Expect only *sz* bytes of buffer to be copied. Helper buffer is used as template. */
+	res_cb = cb_memcpy(s->buffer_to + offset, s->buffer_from, sz);
+	assert_ptr_equal(s->buffer_to + offset, res_cb);
+	assert_memory_equal(s->buffer_to, s->helper_buffer, offset);
+	assert_memory_equal(s->buffer_to + offset, s->buffer_from, sz);
+	assert_memory_equal(s->buffer_to + offset + sz, s->helper_buffer + offset + sz,
+				MEMCPY_BUFFER_SZ - (offset + sz));
+}
+
+static void test_memcpy_buffer_part_unaligned(void **state)
+{
+	struct test_memcpy_data *s = *state;
+	void *res_cb;
+	const size_t dst_offset = MEMCPY_BUFFER_SZ / 8 + 3;
+	const size_t src_offset = MEMCPY_BUFFER_SZ / 4 - 3;
+	const size_t sz = MEMCPY_BUFFER_SZ / 4 + 7;
+
+	/* Self-test for correct data ranges */
+	assert_true(dst_offset + sz <= MEMCPY_BUFFER_SZ);
+	assert_true(src_offset + sz <= MEMCPY_BUFFER_SZ);
+
+	fill_buffer_data_range(s->buffer_from, MEMCPY_BUFFER_SZ, 0x13, 0xB7);
+
+	res_cb = cb_memcpy(s->buffer_to + dst_offset, s->buffer_from + src_offset, sz);
+	assert_ptr_equal(s->buffer_to + dst_offset, res_cb);
+	assert_memory_equal(s->buffer_to, s->helper_buffer, dst_offset);
+	assert_memory_equal(s->buffer_to + dst_offset, s->buffer_from + src_offset, sz);
+	assert_memory_equal(s->buffer_to + dst_offset + sz, s->helper_buffer + dst_offset + sz,
+				MEMCPY_BUFFER_SZ - (dst_offset + sz));
+}
+
+static void test_memcpy_copy_to_itself(void **state)
+{
+	struct test_memcpy_data *s = *state;
+	void *res_cb;
+
+	fill_buffer_data_range(s->buffer_to, MEMCPY_BUFFER_SZ, 'G', 'X');
+	memcpy(s->buffer_to, s->helper_buffer, MEMCPY_BUFFER_SZ);
+
+	/* Expect no change in source/destination buffer. */
+	res_cb = cb_memcpy(s->buffer_to, s->buffer_to, MEMCPY_BUFFER_SZ);
+	assert_ptr_equal(s->buffer_to, res_cb);
+	assert_memory_equal(s->buffer_to, s->helper_buffer, MEMCPY_BUFFER_SZ);
+}
+
+static void test_memcpy_copy_part_of_itself_to_itself(void **state)
+{
+	struct test_memcpy_data *s = *state;
+	void *res_cb;
+	const size_t offset = MEMCPY_BUFFER_SZ / 8;
+	const size_t sz = MEMCPY_BUFFER_SZ - offset;
+
+	/* Self-test for correct data ranges */
+	assert_true(offset + sz <= MEMCPY_BUFFER_SZ);
+
+	fill_buffer_data_range(s->buffer_to, MEMCPY_BUFFER_SZ, 'd', 'v');
+	memcpy(s->helper_buffer, s->buffer_to, MEMCPY_BUFFER_SZ);
+
+	/* Expect only *sz* bytes to be overwritten and *offset* bytes to be left at the end. */
+	res_cb = cb_memcpy(s->buffer_to, s->buffer_to + offset, sz);
+	assert_ptr_equal(s->buffer_to, res_cb);
+	assert_memory_equal(s->buffer_to, s->helper_buffer + offset, sz);
+	assert_memory_equal(s->buffer_to + sz, s->helper_buffer + sz, offset);
+}
+
+int main(void)
+{
+	const struct CMUnitTest tests[] = {
+		cmocka_unit_test_setup_teardown(test_memcpy_full_buffer_copy,
+						setup_test, teardown_test),
+		cmocka_unit_test_setup_teardown(test_memcpy_zero_size,
+						setup_test, teardown_test),
+		cmocka_unit_test_setup_teardown(test_memcpy_buffer_part,
+						setup_test, teardown_test),
+		cmocka_unit_test_setup_teardown(test_memcpy_buffer_part_unaligned,
+						setup_test, teardown_test),
+		cmocka_unit_test_setup_teardown(test_memcpy_copy_to_itself,
+						setup_test, teardown_test),
+		cmocka_unit_test_setup_teardown(test_memcpy_copy_part_of_itself_to_itself,
+						setup_test, teardown_test),
+	};
+
+	return cmocka_run_group_tests(tests, NULL, NULL);
+}