// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
/*
 * Test cases for lib/string_helpers.c module.
 */
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <kunit/test.h>
#include <linux/array_size.h>
#include <linux/kernel.h>
#include <linux/random.h>
#include <linux/string.h>
#include <linux/string_helpers.h>

static void test_string_check_buf(struct kunit *test,
				  const char *name, unsigned int flags,
				  char *in, size_t p,
				  char *out_real, size_t q_real,
				  char *out_test, size_t q_test)
{
	KUNIT_ASSERT_EQ_MSG(test, q_real, q_test, "name:%s", name);
	KUNIT_EXPECT_MEMEQ_MSG(test, out_test, out_real, q_test,
			       "name:%s", name);
}

struct test_string {
	const char *in;
	const char *out;
	unsigned int flags;
};

static const struct test_string strings[] = {
	{
		.in = "\\f\\ \\n\\r\\t\\v",
		.out = "\f\\ \n\r\t\v",
		.flags = UNESCAPE_SPACE,
	},
	{
		.in = "\\40\\1\\387\\0064\\05\\040\\8a\\110\\777",
		.out = " \001\00387\0064\005 \\8aH?7",
		.flags = UNESCAPE_OCTAL,
	},
	{
		.in = "\\xv\\xa\\x2c\\xD\\x6f2",
		.out = "\\xv\n,\ro2",
		.flags = UNESCAPE_HEX,
	},
	{
		.in = "\\h\\\\\\\"\\a\\e\\",
		.out = "\\h\\\"\a\e\\",
		.flags = UNESCAPE_SPECIAL,
	},
};

static void test_string_unescape(struct kunit *test,
				 const char *name, unsigned int flags,
				 bool inplace)
{
	int q_real = 256;
	char *in = kunit_kzalloc(test, q_real, GFP_KERNEL);
	char *out_test = kunit_kzalloc(test, q_real, GFP_KERNEL);
	char *out_real = kunit_kzalloc(test, q_real, GFP_KERNEL);
	int i, p = 0, q_test = 0;

	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, in);
	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, out_test);
	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, out_real);

	for (i = 0; i < ARRAY_SIZE(strings); i++) {
		const char *s = strings[i].in;
		int len = strlen(strings[i].in);

		/* Copy string to in buffer */
		memcpy(&in[p], s, len);
		p += len;

		/* Copy expected result for given flags */
		if (flags & strings[i].flags) {
			s = strings[i].out;
			len = strlen(strings[i].out);
		}
		memcpy(&out_test[q_test], s, len);
		q_test += len;
	}
	in[p++] = '\0';

	/* Call string_unescape and compare result */
	if (inplace) {
		memcpy(out_real, in, p);
		if (flags == UNESCAPE_ANY)
			q_real = string_unescape_any_inplace(out_real);
		else
			q_real = string_unescape_inplace(out_real, flags);
	} else if (flags == UNESCAPE_ANY) {
		q_real = string_unescape_any(in, out_real, q_real);
	} else {
		q_real = string_unescape(in, out_real, q_real, flags);
	}

	test_string_check_buf(test, name, flags, in, p - 1, out_real, q_real,
			      out_test, q_test);
}

struct test_string_1 {
	const char *out;
	unsigned int flags;
};

#define	TEST_STRING_2_MAX_S1		32
struct test_string_2 {
	const char *in;
	struct test_string_1 s1[TEST_STRING_2_MAX_S1];
};

#define	TEST_STRING_2_DICT_0		NULL
static const struct test_string_2 escape0[] = {{
	.in = "\f\\ \n\r\t\v",
	.s1 = {{
		.out = "\\f\\ \\n\\r\\t\\v",
		.flags = ESCAPE_SPACE,
	},{
		.out = "\\f\\134\\040\\n\\r\\t\\v",
		.flags = ESCAPE_SPACE | ESCAPE_OCTAL,
	},{
		.out = "\\f\\x5c\\x20\\n\\r\\t\\v",
		.flags = ESCAPE_SPACE | ESCAPE_HEX,
	},{
		/* terminator */
	}}
},{
	.in = "\\h\\\"\a\e\\",
	.s1 = {{
		.out = "\\\\h\\\\\\\"\\a\\e\\\\",
		.flags = ESCAPE_SPECIAL,
	},{
		.out = "\\\\\\150\\\\\\\"\\a\\e\\\\",
		.flags = ESCAPE_SPECIAL | ESCAPE_OCTAL,
	},{
		.out = "\\\\\\x68\\\\\\\"\\a\\e\\\\",
		.flags = ESCAPE_SPECIAL | ESCAPE_HEX,
	},{
		/* terminator */
	}}
},{
	.in = "\eb \\C\007\"\x90\r]",
	.s1 = {{
		.out = "\eb \\C\007\"\x90\\r]",
		.flags = ESCAPE_SPACE,
	},{
		.out = "\\eb \\\\C\\a\\\"\x90\r]",
		.flags = ESCAPE_SPECIAL,
	},{
		.out = "\\eb \\\\C\\a\\\"\x90\\r]",
		.flags = ESCAPE_SPACE | ESCAPE_SPECIAL,
	},{
		.out = "\\033\\142\\040\\134\\103\\007\\042\\220\\015\\135",
		.flags = ESCAPE_OCTAL,
	},{
		.out = "\\033\\142\\040\\134\\103\\007\\042\\220\\r\\135",
		.flags = ESCAPE_SPACE | ESCAPE_OCTAL,
	},{
		.out = "\\e\\142\\040\\\\\\103\\a\\\"\\220\\015\\135",
		.flags = ESCAPE_SPECIAL | ESCAPE_OCTAL,
	},{
		.out = "\\e\\142\\040\\\\\\103\\a\\\"\\220\\r\\135",
		.flags = ESCAPE_SPACE | ESCAPE_SPECIAL | ESCAPE_OCTAL,
	},{
		.out = "\eb \\C\007\"\x90\r]",
		.flags = ESCAPE_NP,
	},{
		.out = "\eb \\C\007\"\x90\\r]",
		.flags = ESCAPE_SPACE | ESCAPE_NP,
	},{
		.out = "\\eb \\C\\a\"\x90\r]",
		.flags = ESCAPE_SPECIAL | ESCAPE_NP,
	},{
		.out = "\\eb \\C\\a\"\x90\\r]",
		.flags = ESCAPE_SPACE | ESCAPE_SPECIAL | ESCAPE_NP,
	},{
		.out = "\\033b \\C\\007\"\\220\\015]",
		.flags = ESCAPE_OCTAL | ESCAPE_NP,
	},{
		.out = "\\033b \\C\\007\"\\220\\r]",
		.flags = ESCAPE_SPACE | ESCAPE_OCTAL | ESCAPE_NP,
	},{
		.out = "\\eb \\C\\a\"\\220\\r]",
		.flags = ESCAPE_SPECIAL | ESCAPE_SPACE | ESCAPE_OCTAL |
			 ESCAPE_NP,
	},{
		.out = "\\x1bb \\C\\x07\"\\x90\\x0d]",
		.flags = ESCAPE_NP | ESCAPE_HEX,
	},{
		/* terminator */
	}}
},{
	.in = "\007 \eb\"\x90\xCF\r",
	.s1 = {{
		.out = "\007 \eb\"\\220\\317\r",
		.flags = ESCAPE_OCTAL | ESCAPE_NA,
	},{
		.out = "\007 \eb\"\\x90\\xcf\r",
		.flags = ESCAPE_HEX | ESCAPE_NA,
	},{
		.out = "\007 \eb\"\x90\xCF\r",
		.flags = ESCAPE_NA,
	},{
		/* terminator */
	}}
},{
	/* terminator */
}};

#define	TEST_STRING_2_DICT_1		"b\\ \t\r\xCF"
static const struct test_string_2 escape1[] = {{
	.in = "\f\\ \n\r\t\v",
	.s1 = {{
		.out = "\f\\134\\040\n\\015\\011\v",
		.flags = ESCAPE_OCTAL,
	},{
		.out = "\f\\x5c\\x20\n\\x0d\\x09\v",
		.flags = ESCAPE_HEX,
	},{
		.out = "\f\\134\\040\n\\015\\011\v",
		.flags = ESCAPE_ANY | ESCAPE_APPEND,
	},{
		.out = "\\014\\134\\040\\012\\015\\011\\013",
		.flags = ESCAPE_OCTAL | ESCAPE_APPEND | ESCAPE_NAP,
	},{
		.out = "\\x0c\\x5c\\x20\\x0a\\x0d\\x09\\x0b",
		.flags = ESCAPE_HEX | ESCAPE_APPEND | ESCAPE_NAP,
	},{
		.out = "\f\\134\\040\n\\015\\011\v",
		.flags = ESCAPE_OCTAL | ESCAPE_APPEND | ESCAPE_NA,
	},{
		.out = "\f\\x5c\\x20\n\\x0d\\x09\v",
		.flags = ESCAPE_HEX | ESCAPE_APPEND | ESCAPE_NA,
	},{
		/* terminator */
	}}
},{
	.in = "\\h\\\"\a\xCF\e\\",
	.s1 = {{
		.out = "\\134h\\134\"\a\\317\e\\134",
		.flags = ESCAPE_OCTAL,
	},{
		.out = "\\134h\\134\"\a\\317\e\\134",
		.flags = ESCAPE_ANY | ESCAPE_APPEND,
	},{
		.out = "\\134h\\134\"\\007\\317\\033\\134",
		.flags = ESCAPE_OCTAL | ESCAPE_APPEND | ESCAPE_NAP,
	},{
		.out = "\\134h\\134\"\a\\317\e\\134",
		.flags = ESCAPE_OCTAL | ESCAPE_APPEND | ESCAPE_NA,
	},{
		/* terminator */
	}}
},{
	.in = "\eb \\C\007\"\x90\r]",
	.s1 = {{
		.out = "\e\\142\\040\\134C\007\"\x90\\015]",
		.flags = ESCAPE_OCTAL,
	},{
		/* terminator */
	}}
},{
	.in = "\007 \eb\"\x90\xCF\r",
	.s1 = {{
		.out = "\007 \eb\"\x90\xCF\r",
		.flags = ESCAPE_NA,
	},{
		.out = "\007 \eb\"\x90\xCF\r",
		.flags = ESCAPE_SPACE | ESCAPE_NA,
	},{
		.out = "\007 \eb\"\x90\xCF\r",
		.flags = ESCAPE_SPECIAL | ESCAPE_NA,
	},{
		.out = "\007 \eb\"\x90\xCF\r",
		.flags = ESCAPE_SPACE | ESCAPE_SPECIAL | ESCAPE_NA,
	},{
		.out = "\007 \eb\"\x90\\317\r",
		.flags = ESCAPE_OCTAL | ESCAPE_NA,
	},{
		.out = "\007 \eb\"\x90\\317\r",
		.flags = ESCAPE_SPACE | ESCAPE_OCTAL | ESCAPE_NA,
	},{
		.out = "\007 \eb\"\x90\\317\r",
		.flags = ESCAPE_SPECIAL | ESCAPE_OCTAL | ESCAPE_NA,
	},{
		.out = "\007 \eb\"\x90\\317\r",
		.flags = ESCAPE_ANY | ESCAPE_NA,
	},{
		.out = "\007 \eb\"\x90\\xcf\r",
		.flags = ESCAPE_HEX | ESCAPE_NA,
	},{
		.out = "\007 \eb\"\x90\\xcf\r",
		.flags = ESCAPE_SPACE | ESCAPE_HEX | ESCAPE_NA,
	},{
		.out = "\007 \eb\"\x90\\xcf\r",
		.flags = ESCAPE_SPECIAL | ESCAPE_HEX | ESCAPE_NA,
	},{
		.out = "\007 \eb\"\x90\\xcf\r",
		.flags = ESCAPE_SPACE | ESCAPE_SPECIAL | ESCAPE_HEX | ESCAPE_NA,
	},{
		/* terminator */
	}}
},{
	.in = "\007 \eb\"\x90\xCF\r",
	.s1 = {{
		.out = "\007 \eb\"\x90\xCF\r",
		.flags = ESCAPE_NAP,
	},{
		.out = "\007 \eb\"\x90\xCF\\r",
		.flags = ESCAPE_SPACE | ESCAPE_NAP,
	},{
		.out = "\007 \eb\"\x90\xCF\r",
		.flags = ESCAPE_SPECIAL | ESCAPE_NAP,
	},{
		.out = "\007 \eb\"\x90\xCF\\r",
		.flags = ESCAPE_SPACE | ESCAPE_SPECIAL | ESCAPE_NAP,
	},{
		.out = "\007 \eb\"\x90\\317\\015",
		.flags = ESCAPE_OCTAL | ESCAPE_NAP,
	},{
		.out = "\007 \eb\"\x90\\317\\r",
		.flags = ESCAPE_SPACE | ESCAPE_OCTAL | ESCAPE_NAP,
	},{
		.out = "\007 \eb\"\x90\\317\\015",
		.flags = ESCAPE_SPECIAL | ESCAPE_OCTAL | ESCAPE_NAP,
	},{
		.out = "\007 \eb\"\x90\\317\r",
		.flags = ESCAPE_ANY | ESCAPE_NAP,
	},{
		.out = "\007 \eb\"\x90\\xcf\\x0d",
		.flags = ESCAPE_HEX | ESCAPE_NAP,
	},{
		.out = "\007 \eb\"\x90\\xcf\\r",
		.flags = ESCAPE_SPACE | ESCAPE_HEX | ESCAPE_NAP,
	},{
		.out = "\007 \eb\"\x90\\xcf\\x0d",
		.flags = ESCAPE_SPECIAL | ESCAPE_HEX | ESCAPE_NAP,
	},{
		.out = "\007 \eb\"\x90\\xcf\\r",
		.flags = ESCAPE_SPACE | ESCAPE_SPECIAL | ESCAPE_HEX | ESCAPE_NAP,
	},{
		/* terminator */
	}}
},{
	/* terminator */
}};

static const struct test_string strings_upper[] = {
	{
		.in = "abcdefgh1234567890test",
		.out = "ABCDEFGH1234567890TEST",
	},
	{
		.in = "abCdeFgH1234567890TesT",
		.out = "ABCDEFGH1234567890TEST",
	},
};

static const struct test_string strings_lower[] = {
	{
		.in = "ABCDEFGH1234567890TEST",
		.out = "abcdefgh1234567890test",
	},
	{
		.in = "abCdeFgH1234567890TesT",
		.out = "abcdefgh1234567890test",
	},
};

static const char *test_string_find_match(const struct test_string_2 *s2,
					  unsigned int flags)
{
	const struct test_string_1 *s1 = s2->s1;
	unsigned int i;

	if (!flags)
		return s2->in;

	/* Test cases are NULL-aware */
	flags &= ~ESCAPE_NULL;

	/* ESCAPE_OCTAL has a higher priority */
	if (flags & ESCAPE_OCTAL)
		flags &= ~ESCAPE_HEX;

	for (i = 0; i < TEST_STRING_2_MAX_S1 && s1->out; i++, s1++)
		if (s1->flags == flags)
			return s1->out;
	return NULL;
}

static void
test_string_escape_overflow(struct kunit *test,
			    const char *in, int p, unsigned int flags, const char *esc,
			    int q_test, const char *name)
{
	int q_real;

	q_real = string_escape_mem(in, p, NULL, 0, flags, esc);
	KUNIT_EXPECT_EQ_MSG(test, q_real, q_test, "name:%s: flags:%#x", name, flags);
}

static void test_string_escape(struct kunit *test, const char *name,
			       const struct test_string_2 *s2,
			       unsigned int flags, const char *esc)
{
	size_t out_size = 512;
	char *out_test = kunit_kzalloc(test, out_size, GFP_KERNEL);
	char *out_real = kunit_kzalloc(test, out_size, GFP_KERNEL);
	char *in = kunit_kzalloc(test, 256, GFP_KERNEL);
	int p = 0, q_test = 0;
	int q_real;

	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, out_test);
	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, out_real);
	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, in);

	for (; s2->in; s2++) {
		const char *out;
		int len;

		/* NULL injection */
		if (flags & ESCAPE_NULL) {
			in[p++] = '\0';
			/* '\0' passes isascii() test */
			if (flags & ESCAPE_NA && !(flags & ESCAPE_APPEND && esc)) {
				out_test[q_test++] = '\0';
			} else {
				out_test[q_test++] = '\\';
				out_test[q_test++] = '0';
			}
		}

		/* Don't try strings that have no output */
		out = test_string_find_match(s2, flags);
		if (!out)
			continue;

		/* Copy string to in buffer */
		len = strlen(s2->in);
		memcpy(&in[p], s2->in, len);
		p += len;

		/* Copy expected result for given flags */
		len = strlen(out);
		memcpy(&out_test[q_test], out, len);
		q_test += len;
	}

	q_real = string_escape_mem(in, p, out_real, out_size, flags, esc);

	test_string_check_buf(test, name, flags, in, p, out_real, q_real, out_test,
			      q_test);

	test_string_escape_overflow(test, in, p, flags, esc, q_test, name);
}

#define string_get_size_maxbuf 16
#define test_string_get_size_one(size, blk_size, exp_result10, exp_result2)      \
	do {                                                                     \
		BUILD_BUG_ON(sizeof(exp_result10) >= string_get_size_maxbuf);    \
		BUILD_BUG_ON(sizeof(exp_result2) >= string_get_size_maxbuf);     \
		__test_string_get_size(test, (size), (blk_size), (exp_result10), \
				       (exp_result2));                           \
	} while (0)


static void test_string_get_size_check(struct kunit *test,
				       const char *units,
				       const char *exp,
				       char *res,
				       const u64 size,
				       const u64 blk_size)
{
	KUNIT_EXPECT_MEMEQ_MSG(test, res, exp, strlen(exp) + 1,
		"string_get_size(size = %llu, blk_size = %llu, units = %s)",
		size, blk_size, units);
}

static void __strchrcut(char *dst, const char *src, const char *cut)
{
	const char *from = src;
	size_t len;

	do {
		len = strcspn(from, cut);
		memcpy(dst, from, len);
		dst += len;
		from += len;
	} while (*from++);
	*dst = '\0';
}

static void __test_string_get_size_one(struct kunit *test,
				       const u64 size, const u64 blk_size,
				       const char *exp_result10,
				       const char *exp_result2,
				       enum string_size_units units,
				       const char *cut)
{
	char buf10[string_get_size_maxbuf];
	char buf2[string_get_size_maxbuf];
	char exp10[string_get_size_maxbuf];
	char exp2[string_get_size_maxbuf];
	char prefix10[64];
	char prefix2[64];

	sprintf(prefix10, "STRING_UNITS_10 [%s]", cut);
	sprintf(prefix2, "STRING_UNITS_2 [%s]", cut);

	__strchrcut(exp10, exp_result10, cut);
	__strchrcut(exp2, exp_result2, cut);

	string_get_size(size, blk_size, STRING_UNITS_10 | units, buf10, sizeof(buf10));
	string_get_size(size, blk_size, STRING_UNITS_2 | units, buf2, sizeof(buf2));

	test_string_get_size_check(test, prefix10, exp10, buf10, size, blk_size);
	test_string_get_size_check(test, prefix2, exp2, buf2, size, blk_size);
}

static void __test_string_get_size(struct kunit *test,
				   const u64 size, const u64 blk_size,
				   const char *exp_result10,
				   const char *exp_result2)
{
	struct {
		enum string_size_units units;
		const char *cut;
	} get_size_test_cases[] = {
		{ 0, "" },
		{ STRING_UNITS_NO_SPACE, " " },
		{ STRING_UNITS_NO_SPACE | STRING_UNITS_NO_BYTES, " B" },
		{ STRING_UNITS_NO_BYTES, "B" },
	};
	int i;

	for (i = 0; i < ARRAY_SIZE(get_size_test_cases); i++)
		__test_string_get_size_one(test, size, blk_size,
					   exp_result10, exp_result2,
					   get_size_test_cases[i].units,
					   get_size_test_cases[i].cut);
}

static void test_get_size(struct kunit *test)
{
	/* small values */
	test_string_get_size_one(0, 512, "0 B", "0 B");
	test_string_get_size_one(1, 512, "512 B", "512 B");
	test_string_get_size_one(1100, 1, "1.10 kB", "1.07 KiB");

	/* normal values */
	test_string_get_size_one(16384, 512, "8.39 MB", "8.00 MiB");
	test_string_get_size_one(500118192, 512, "256 GB", "238 GiB");
	test_string_get_size_one(8192, 4096, "33.6 MB", "32.0 MiB");

	/* weird block sizes */
	test_string_get_size_one(3000, 1900, "5.70 MB", "5.44 MiB");

	/* huge values */
	test_string_get_size_one(U64_MAX, 4096, "75.6 ZB", "64.0 ZiB");
	test_string_get_size_one(4096, U64_MAX, "75.6 ZB", "64.0 ZiB");
}

static void test_upper_lower(struct kunit *test)
{
	char *dst;
	int i;

	for (i = 0; i < ARRAY_SIZE(strings_upper); i++) {
		const char *s = strings_upper[i].in;
		int len = strlen(strings_upper[i].in) + 1;

		dst = kmalloc(len, GFP_KERNEL);
		KUNIT_ASSERT_NOT_NULL(test, dst);

		string_upper(dst, s);
		KUNIT_EXPECT_STREQ(test, dst, strings_upper[i].out);
		kfree(dst);
	}

	for (i = 0; i < ARRAY_SIZE(strings_lower); i++) {
		const char *s = strings_lower[i].in;
		int len = strlen(strings_lower[i].in) + 1;

		dst = kmalloc(len, GFP_KERNEL);
		KUNIT_ASSERT_NOT_NULL(test, dst);

		string_lower(dst, s);
		KUNIT_EXPECT_STREQ(test, dst, strings_lower[i].out);
		kfree(dst);
	}
}

static void test_unescape(struct kunit *test)
{
	unsigned int i;

	for (i = 0; i < UNESCAPE_ALL_MASK + 1; i++)
		test_string_unescape(test, "unescape", i, false);
	test_string_unescape(test, "unescape inplace",
			     get_random_u32_below(UNESCAPE_ALL_MASK + 1), true);

	/* Without dictionary */
	for (i = 0; i < ESCAPE_ALL_MASK + 1; i++)
		test_string_escape(test, "escape 0", escape0, i, TEST_STRING_2_DICT_0);

	/* With dictionary */
	for (i = 0; i < ESCAPE_ALL_MASK + 1; i++)
		test_string_escape(test, "escape 1", escape1, i, TEST_STRING_2_DICT_1);
}

static struct kunit_case string_helpers_test_cases[] = {
	KUNIT_CASE(test_get_size),
	KUNIT_CASE(test_upper_lower),
	KUNIT_CASE(test_unescape),
	{}
};

static struct kunit_suite string_helpers_test_suite = {
	.name = "string_helpers",
	.test_cases = string_helpers_test_cases,
};

kunit_test_suites(&string_helpers_test_suite);

MODULE_DESCRIPTION("Test cases for string helpers module");
MODULE_LICENSE("Dual BSD/GPL");