1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Test cases for memcat_p() in lib/memcat_p.c
  4 */
  5#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  6
  7#include <linux/string.h>
  8#include <linux/slab.h>
  9#include <linux/module.h>
 10
 11struct test_struct {
 12	int		num;
 13	unsigned int	magic;
 14};
 15
 16#define MAGIC		0xf00ff00f
 17/* Size of each of the NULL-terminated input arrays */
 18#define INPUT_MAX	128
 19/* Expected number of non-NULL elements in the output array */
 20#define EXPECT		(INPUT_MAX * 2 - 2)
 21
 22static int __init test_memcat_p_init(void)
 23{
 24	struct test_struct **in0, **in1, **out, **p;
 25	int err = -ENOMEM, i, r, total = 0;
 26
 27	in0 = kcalloc(INPUT_MAX, sizeof(*in0), GFP_KERNEL);
 28	if (!in0)
 29		return err;
 30
 31	in1 = kcalloc(INPUT_MAX, sizeof(*in1), GFP_KERNEL);
 32	if (!in1)
 33		goto err_free_in0;
 34
 35	for (i = 0, r = 1; i < INPUT_MAX - 1; i++) {
 36		in0[i] = kmalloc(sizeof(**in0), GFP_KERNEL);
 37		if (!in0[i])
 38			goto err_free_elements;
 39
 40		in1[i] = kmalloc(sizeof(**in1), GFP_KERNEL);
 41		if (!in1[i]) {
 42			kfree(in0[i]);
 43			goto err_free_elements;
 44		}
 45
 46		/* lifted from test_sort.c */
 47		r = (r * 725861) % 6599;
 48		in0[i]->num = r;
 49		in1[i]->num = -r;
 50		in0[i]->magic = MAGIC;
 51		in1[i]->magic = MAGIC;
 52	}
 53
 54	in0[i] = in1[i] = NULL;
 55
 56	out = memcat_p(in0, in1);
 57	if (!out)
 58		goto err_free_all_elements;
 59
 60	err = -EINVAL;
 61	for (i = 0, p = out; *p && (i < INPUT_MAX * 2 - 1); p++, i++) {
 62		total += (*p)->num;
 63
 64		if ((*p)->magic != MAGIC) {
 65			pr_err("test failed: wrong magic at %d: %u\n", i,
 66			       (*p)->magic);
 67			goto err_free_out;
 68		}
 69	}
 70
 71	if (total) {
 72		pr_err("test failed: expected zero total, got %d\n", total);
 73		goto err_free_out;
 74	}
 75
 76	if (i != EXPECT) {
 77		pr_err("test failed: expected output size %d, got %d\n",
 78		       EXPECT, i);
 79		goto err_free_out;
 80	}
 81
 82	for (i = 0; i < INPUT_MAX - 1; i++)
 83		if (out[i] != in0[i] || out[i + INPUT_MAX - 1] != in1[i]) {
 84			pr_err("test failed: wrong element order at %d\n", i);
 85			goto err_free_out;
 86		}
 87
 88	err = 0;
 89	pr_info("test passed\n");
 90
 91err_free_out:
 92	kfree(out);
 93err_free_all_elements:
 94	i = INPUT_MAX;
 95err_free_elements:
 96	for (i--; i >= 0; i--) {
 97		kfree(in1[i]);
 98		kfree(in0[i]);
 99	}
100
101	kfree(in1);
102err_free_in0:
103	kfree(in0);
104
105	return err;
106}
107
108static void __exit test_memcat_p_exit(void)
109{
110}
111
112module_init(test_memcat_p_init);
113module_exit(test_memcat_p_exit);
114
115MODULE_LICENSE("GPL");