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linux/lib/test_bitmap.c
Yury Norov 809e308f7f lib: new testcases for bitmap_parse{_user} 
New version of bitmap_parse() is unified with bitmap_parse_list(),
and therefore:

- weakens rules on whitespaces and commas between hex chunks;

- in addition to

- allows passing UINT_MAX or any other big number as the length of input
  string instead of actual string length.

The patch covers the cases.

Link: http://lkml.kernel.org/r/20200102043031.30357-7-yury.norov@gmail.com
Signed-off-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Amritha Nambiar <amritha.nambiar@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: "Tobin C . Harding" <tobin@kernel.org>
Cc: Vineet Gupta <vineet.gupta1@synopsys.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-02-04 03:05:27 +00:00

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// SPDX-License-Identifier: GPL-2.0-only
/*
* Test cases for bitmap API.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/bitmap.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/printk.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/uaccess.h>
#include "../tools/testing/selftests/kselftest_module.h"
static unsigned total_tests __initdata;
static unsigned failed_tests __initdata;
static char pbl_buffer[PAGE_SIZE] __initdata;
static const unsigned long exp1[] __initconst = {
BITMAP_FROM_U64(1),
BITMAP_FROM_U64(2),
BITMAP_FROM_U64(0x0000ffff),
BITMAP_FROM_U64(0xffff0000),
BITMAP_FROM_U64(0x55555555),
BITMAP_FROM_U64(0xaaaaaaaa),
BITMAP_FROM_U64(0x11111111),
BITMAP_FROM_U64(0x22222222),
BITMAP_FROM_U64(0xffffffff),
BITMAP_FROM_U64(0xfffffffe),
BITMAP_FROM_U64(0x3333333311111111ULL),
BITMAP_FROM_U64(0xffffffff77777777ULL),
BITMAP_FROM_U64(0),
};
static const unsigned long exp2[] __initconst = {
BITMAP_FROM_U64(0x3333333311111111ULL),
BITMAP_FROM_U64(0xffffffff77777777ULL),
};
/* Fibonacci sequence */
static const unsigned long exp2_to_exp3_mask[] __initconst = {
BITMAP_FROM_U64(0x008000020020212eULL),
};
/* exp3_0_1 = (exp2[0] & ~exp2_to_exp3_mask) | (exp2[1] & exp2_to_exp3_mask) */
static const unsigned long exp3_0_1[] __initconst = {
BITMAP_FROM_U64(0x33b3333311313137ULL),
};
/* exp3_1_0 = (exp2[1] & ~exp2_to_exp3_mask) | (exp2[0] & exp2_to_exp3_mask) */
static const unsigned long exp3_1_0[] __initconst = {
BITMAP_FROM_U64(0xff7fffff77575751ULL),
};
static bool __init
__check_eq_uint(const char *srcfile, unsigned int line,
const unsigned int exp_uint, unsigned int x)
{
if (exp_uint != x) {
pr_err("[%s:%u] expected %u, got %u\n",
srcfile, line, exp_uint, x);
return false;
}
return true;
}
static bool __init
__check_eq_bitmap(const char *srcfile, unsigned int line,
const unsigned long *exp_bmap, const unsigned long *bmap,
unsigned int nbits)
{
if (!bitmap_equal(exp_bmap, bmap, nbits)) {
pr_warn("[%s:%u] bitmaps contents differ: expected \"%*pbl\", got \"%*pbl\"\n",
srcfile, line,
nbits, exp_bmap, nbits, bmap);
return false;
}
return true;
}
static bool __init
__check_eq_pbl(const char *srcfile, unsigned int line,
const char *expected_pbl,
const unsigned long *bitmap, unsigned int nbits)
{
snprintf(pbl_buffer, sizeof(pbl_buffer), "%*pbl", nbits, bitmap);
if (strcmp(expected_pbl, pbl_buffer)) {
pr_warn("[%s:%u] expected \"%s\", got \"%s\"\n",
srcfile, line,
expected_pbl, pbl_buffer);
return false;
}
return true;
}
static bool __init
__check_eq_u32_array(const char *srcfile, unsigned int line,
const u32 *exp_arr, unsigned int exp_len,
const u32 *arr, unsigned int len) __used;
static bool __init
__check_eq_u32_array(const char *srcfile, unsigned int line,
const u32 *exp_arr, unsigned int exp_len,
const u32 *arr, unsigned int len)
{
if (exp_len != len) {
pr_warn("[%s:%u] array length differ: expected %u, got %u\n",
srcfile, line,
exp_len, len);
return false;
}
if (memcmp(exp_arr, arr, len*sizeof(*arr))) {
pr_warn("[%s:%u] array contents differ\n", srcfile, line);
print_hex_dump(KERN_WARNING, " exp: ", DUMP_PREFIX_OFFSET,
32, 4, exp_arr, exp_len*sizeof(*exp_arr), false);
print_hex_dump(KERN_WARNING, " got: ", DUMP_PREFIX_OFFSET,
32, 4, arr, len*sizeof(*arr), false);
return false;
}
return true;
}
static bool __init __check_eq_clump8(const char *srcfile, unsigned int line,
const unsigned int offset,
const unsigned int size,
const unsigned char *const clump_exp,
const unsigned long *const clump)
{
unsigned long exp;
if (offset >= size) {
pr_warn("[%s:%u] bit offset for clump out-of-bounds: expected less than %u, got %u\n",
srcfile, line, size, offset);
return false;
}
exp = clump_exp[offset / 8];
if (!exp) {
pr_warn("[%s:%u] bit offset for zero clump: expected nonzero clump, got bit offset %u with clump value 0",
srcfile, line, offset);
return false;
}
if (*clump != exp) {
pr_warn("[%s:%u] expected clump value of 0x%lX, got clump value of 0x%lX",
srcfile, line, exp, *clump);
return false;
}
return true;
}
#define __expect_eq(suffix, ...) \
({ \
int result = 0; \
total_tests++; \
if (!__check_eq_ ## suffix(__FILE__, __LINE__, \
##__VA_ARGS__)) { \
failed_tests++; \
result = 1; \
} \
result; \
})
#define expect_eq_uint(...) __expect_eq(uint, ##__VA_ARGS__)
#define expect_eq_bitmap(...) __expect_eq(bitmap, ##__VA_ARGS__)
#define expect_eq_pbl(...) __expect_eq(pbl, ##__VA_ARGS__)
#define expect_eq_u32_array(...) __expect_eq(u32_array, ##__VA_ARGS__)
#define expect_eq_clump8(...) __expect_eq(clump8, ##__VA_ARGS__)
static void __init test_zero_clear(void)
{
DECLARE_BITMAP(bmap, 1024);
/* Known way to set all bits */
memset(bmap, 0xff, 128);
expect_eq_pbl("0-22", bmap, 23);
expect_eq_pbl("0-1023", bmap, 1024);
/* single-word bitmaps */
bitmap_clear(bmap, 0, 9);
expect_eq_pbl("9-1023", bmap, 1024);
bitmap_zero(bmap, 35);
expect_eq_pbl("64-1023", bmap, 1024);
/* cross boundaries operations */
bitmap_clear(bmap, 79, 19);
expect_eq_pbl("64-78,98-1023", bmap, 1024);
bitmap_zero(bmap, 115);
expect_eq_pbl("128-1023", bmap, 1024);
/* Zeroing entire area */
bitmap_zero(bmap, 1024);
expect_eq_pbl("", bmap, 1024);
}
static void __init test_fill_set(void)
{
DECLARE_BITMAP(bmap, 1024);
/* Known way to clear all bits */
memset(bmap, 0x00, 128);
expect_eq_pbl("", bmap, 23);
expect_eq_pbl("", bmap, 1024);
/* single-word bitmaps */
bitmap_set(bmap, 0, 9);
expect_eq_pbl("0-8", bmap, 1024);
bitmap_fill(bmap, 35);
expect_eq_pbl("0-63", bmap, 1024);
/* cross boundaries operations */
bitmap_set(bmap, 79, 19);
expect_eq_pbl("0-63,79-97", bmap, 1024);
bitmap_fill(bmap, 115);
expect_eq_pbl("0-127", bmap, 1024);
/* Zeroing entire area */
bitmap_fill(bmap, 1024);
expect_eq_pbl("0-1023", bmap, 1024);
}
static void __init test_copy(void)
{
DECLARE_BITMAP(bmap1, 1024);
DECLARE_BITMAP(bmap2, 1024);
bitmap_zero(bmap1, 1024);
bitmap_zero(bmap2, 1024);
/* single-word bitmaps */
bitmap_set(bmap1, 0, 19);
bitmap_copy(bmap2, bmap1, 23);
expect_eq_pbl("0-18", bmap2, 1024);
bitmap_set(bmap2, 0, 23);
bitmap_copy(bmap2, bmap1, 23);
expect_eq_pbl("0-18", bmap2, 1024);
/* multi-word bitmaps */
bitmap_set(bmap1, 0, 109);
bitmap_copy(bmap2, bmap1, 1024);
expect_eq_pbl("0-108", bmap2, 1024);
bitmap_fill(bmap2, 1024);
bitmap_copy(bmap2, bmap1, 1024);
expect_eq_pbl("0-108", bmap2, 1024);
/* the following tests assume a 32- or 64-bit arch (even 128b
* if we care)
*/
bitmap_fill(bmap2, 1024);
bitmap_copy(bmap2, bmap1, 109); /* ... but 0-padded til word length */
expect_eq_pbl("0-108,128-1023", bmap2, 1024);
bitmap_fill(bmap2, 1024);
bitmap_copy(bmap2, bmap1, 97); /* ... but aligned on word length */
expect_eq_pbl("0-108,128-1023", bmap2, 1024);
}
#define EXP2_IN_BITS (sizeof(exp2) * 8)
static void __init test_replace(void)
{
unsigned int nbits = 64;
unsigned int nlongs = DIV_ROUND_UP(nbits, BITS_PER_LONG);
DECLARE_BITMAP(bmap, 1024);
bitmap_zero(bmap, 1024);
bitmap_replace(bmap, &exp2[0 * nlongs], &exp2[1 * nlongs], exp2_to_exp3_mask, nbits);
expect_eq_bitmap(bmap, exp3_0_1, nbits);
bitmap_zero(bmap, 1024);
bitmap_replace(bmap, &exp2[1 * nlongs], &exp2[0 * nlongs], exp2_to_exp3_mask, nbits);
expect_eq_bitmap(bmap, exp3_1_0, nbits);
bitmap_fill(bmap, 1024);
bitmap_replace(bmap, &exp2[0 * nlongs], &exp2[1 * nlongs], exp2_to_exp3_mask, nbits);
expect_eq_bitmap(bmap, exp3_0_1, nbits);
bitmap_fill(bmap, 1024);
bitmap_replace(bmap, &exp2[1 * nlongs], &exp2[0 * nlongs], exp2_to_exp3_mask, nbits);
expect_eq_bitmap(bmap, exp3_1_0, nbits);
}
#define PARSE_TIME 0x1
#define NO_LEN 0x2
struct test_bitmap_parselist{
const int errno;
const char *in;
const unsigned long *expected;
const int nbits;
const int flags;
};
static const struct test_bitmap_parselist parselist_tests[] __initconst = {
#define step (sizeof(u64) / sizeof(unsigned long))
{0, "0", &exp1[0], 8, 0},
{0, "1", &exp1[1 * step], 8, 0},
{0, "0-15", &exp1[2 * step], 32, 0},
{0, "16-31", &exp1[3 * step], 32, 0},
{0, "0-31:1/2", &exp1[4 * step], 32, 0},
{0, "1-31:1/2", &exp1[5 * step], 32, 0},
{0, "0-31:1/4", &exp1[6 * step], 32, 0},
{0, "1-31:1/4", &exp1[7 * step], 32, 0},
{0, "0-31:4/4", &exp1[8 * step], 32, 0},
{0, "1-31:4/4", &exp1[9 * step], 32, 0},
{0, "0-31:1/4,32-63:2/4", &exp1[10 * step], 64, 0},
{0, "0-31:3/4,32-63:4/4", &exp1[11 * step], 64, 0},
{0, " ,, 0-31:3/4 ,, 32-63:4/4 ,, ", &exp1[11 * step], 64, 0},
{0, "0-31:1/4,32-63:2/4,64-95:3/4,96-127:4/4", exp2, 128, 0},
{0, "0-2047:128/256", NULL, 2048, PARSE_TIME},
{0, "", &exp1[12 * step], 8, 0},
{0, "\n", &exp1[12 * step], 8, 0},
{0, ",, ,, , , ,", &exp1[12 * step], 8, 0},
{0, " , ,, , , ", &exp1[12 * step], 8, 0},
{0, " , ,, , , \n", &exp1[12 * step], 8, 0},
{-EINVAL, "-1", NULL, 8, 0},
{-EINVAL, "-0", NULL, 8, 0},
{-EINVAL, "10-1", NULL, 8, 0},
{-EINVAL, "0-31:", NULL, 8, 0},
{-EINVAL, "0-31:0", NULL, 8, 0},
{-EINVAL, "0-31:0/", NULL, 8, 0},
{-EINVAL, "0-31:0/0", NULL, 8, 0},
{-EINVAL, "0-31:1/0", NULL, 8, 0},
{-EINVAL, "0-31:10/1", NULL, 8, 0},
{-EOVERFLOW, "0-98765432123456789:10/1", NULL, 8, 0},
{-EINVAL, "a-31", NULL, 8, 0},
{-EINVAL, "0-a1", NULL, 8, 0},
{-EINVAL, "a-31:10/1", NULL, 8, 0},
{-EINVAL, "0-31:a/1", NULL, 8, 0},
{-EINVAL, "0-\n", NULL, 8, 0},
};
static void __init __test_bitmap_parselist(int is_user)
{
int i;
int err;
ktime_t time;
DECLARE_BITMAP(bmap, 2048);
char *mode = is_user ? "_user" : "";
for (i = 0; i < ARRAY_SIZE(parselist_tests); i++) {
#define ptest parselist_tests[i]
if (is_user) {
mm_segment_t orig_fs = get_fs();
size_t len = strlen(ptest.in);
set_fs(KERNEL_DS);
time = ktime_get();
err = bitmap_parselist_user((__force const char __user *)ptest.in, len,
bmap, ptest.nbits);
time = ktime_get() - time;
set_fs(orig_fs);
} else {
time = ktime_get();
err = bitmap_parselist(ptest.in, bmap, ptest.nbits);
time = ktime_get() - time;
}
if (err != ptest.errno) {
pr_err("parselist%s: %d: input is %s, errno is %d, expected %d\n",
mode, i, ptest.in, err, ptest.errno);
continue;
}
if (!err && ptest.expected
&& !__bitmap_equal(bmap, ptest.expected, ptest.nbits)) {
pr_err("parselist%s: %d: input is %s, result is 0x%lx, expected 0x%lx\n",
mode, i, ptest.in, bmap[0],
*ptest.expected);
continue;
}
if (ptest.flags & PARSE_TIME)
pr_err("parselist%s: %d: input is '%s' OK, Time: %llu\n",
mode, i, ptest.in, time);
#undef ptest
}
}
static const unsigned long parse_test[] __initconst = {
BITMAP_FROM_U64(0),
BITMAP_FROM_U64(1),
BITMAP_FROM_U64(0xdeadbeef),
BITMAP_FROM_U64(0x100000000ULL),
};
static const unsigned long parse_test2[] __initconst = {
BITMAP_FROM_U64(0x100000000ULL), BITMAP_FROM_U64(0xdeadbeef),
BITMAP_FROM_U64(0x100000000ULL), BITMAP_FROM_U64(0xbaadf00ddeadbeef),
BITMAP_FROM_U64(0x100000000ULL), BITMAP_FROM_U64(0x0badf00ddeadbeef),
};
static const struct test_bitmap_parselist parse_tests[] __initconst = {
{0, "", &parse_test[0 * step], 32, 0},
{0, " ", &parse_test[0 * step], 32, 0},
{0, "0", &parse_test[0 * step], 32, 0},
{0, "0\n", &parse_test[0 * step], 32, 0},
{0, "1", &parse_test[1 * step], 32, 0},
{0, "deadbeef", &parse_test[2 * step], 32, 0},
{0, "1,0", &parse_test[3 * step], 33, 0},
{0, "deadbeef,\n,0,1", &parse_test[2 * step], 96, 0},
{0, "deadbeef,1,0", &parse_test2[0 * 2 * step], 96, 0},
{0, "baadf00d,deadbeef,1,0", &parse_test2[1 * 2 * step], 128, 0},
{0, "badf00d,deadbeef,1,0", &parse_test2[2 * 2 * step], 124, 0},
{0, "badf00d,deadbeef,1,0", &parse_test2[2 * 2 * step], 124, NO_LEN},
{0, " badf00d,deadbeef,1,0 ", &parse_test2[2 * 2 * step], 124, 0},
{0, " , badf00d,deadbeef,1,0 , ", &parse_test2[2 * 2 * step], 124, 0},
{0, " , badf00d, ,, ,,deadbeef,1,0 , ", &parse_test2[2 * 2 * step], 124, 0},
{-EINVAL, "goodfood,deadbeef,1,0", NULL, 128, 0},
{-EOVERFLOW, "3,0", NULL, 33, 0},
{-EOVERFLOW, "123badf00d,deadbeef,1,0", NULL, 128, 0},
{-EOVERFLOW, "badf00d,deadbeef,1,0", NULL, 90, 0},
{-EOVERFLOW, "fbadf00d,deadbeef,1,0", NULL, 95, 0},
{-EOVERFLOW, "badf00d,deadbeef,1,0", NULL, 100, 0},
#undef step
};
static void __init __test_bitmap_parse(int is_user)
{
int i;
int err;
ktime_t time;
DECLARE_BITMAP(bmap, 2048);
char *mode = is_user ? "_user" : "";
for (i = 0; i < ARRAY_SIZE(parse_tests); i++) {
struct test_bitmap_parselist test = parse_tests[i];
if (is_user) {
size_t len = strlen(test.in);
mm_segment_t orig_fs = get_fs();
set_fs(KERNEL_DS);
time = ktime_get();
err = bitmap_parse_user((__force const char __user *)test.in, len,
bmap, test.nbits);
time = ktime_get() - time;
set_fs(orig_fs);
} else {
size_t len = test.flags & NO_LEN ?
UINT_MAX : strlen(test.in);
time = ktime_get();
err = bitmap_parse(test.in, len, bmap, test.nbits);
time = ktime_get() - time;
}
if (err != test.errno) {
pr_err("parse%s: %d: input is %s, errno is %d, expected %d\n",
mode, i, test.in, err, test.errno);
continue;
}
if (!err && test.expected
&& !__bitmap_equal(bmap, test.expected, test.nbits)) {
pr_err("parse%s: %d: input is %s, result is 0x%lx, expected 0x%lx\n",
mode, i, test.in, bmap[0],
*test.expected);
continue;
}
if (test.flags & PARSE_TIME)
pr_err("parse%s: %d: input is '%s' OK, Time: %llu\n",
mode, i, test.in, time);
}
}
static void __init test_bitmap_parselist(void)
{
__test_bitmap_parselist(0);
}
static void __init test_bitmap_parselist_user(void)
{
__test_bitmap_parselist(1);
}
static void __init test_bitmap_parse(void)
{
__test_bitmap_parse(0);
}
static void __init test_bitmap_parse_user(void)
{
__test_bitmap_parse(1);
}
#define EXP1_IN_BITS (sizeof(exp1) * 8)
static void __init test_bitmap_arr32(void)
{
unsigned int nbits, next_bit;
u32 arr[EXP1_IN_BITS / 32];
DECLARE_BITMAP(bmap2, EXP1_IN_BITS);
memset(arr, 0xa5, sizeof(arr));
for (nbits = 0; nbits < EXP1_IN_BITS; ++nbits) {
bitmap_to_arr32(arr, exp1, nbits);
bitmap_from_arr32(bmap2, arr, nbits);
expect_eq_bitmap(bmap2, exp1, nbits);
next_bit = find_next_bit(bmap2,
round_up(nbits, BITS_PER_LONG), nbits);
if (next_bit < round_up(nbits, BITS_PER_LONG))
pr_err("bitmap_copy_arr32(nbits == %d:"
" tail is not safely cleared: %d\n",
nbits, next_bit);
if (nbits < EXP1_IN_BITS - 32)
expect_eq_uint(arr[DIV_ROUND_UP(nbits, 32)],
0xa5a5a5a5);
}
}
static void noinline __init test_mem_optimisations(void)
{
DECLARE_BITMAP(bmap1, 1024);
DECLARE_BITMAP(bmap2, 1024);
unsigned int start, nbits;
for (start = 0; start < 1024; start += 8) {
for (nbits = 0; nbits < 1024 - start; nbits += 8) {
memset(bmap1, 0x5a, sizeof(bmap1));
memset(bmap2, 0x5a, sizeof(bmap2));
bitmap_set(bmap1, start, nbits);
__bitmap_set(bmap2, start, nbits);
if (!bitmap_equal(bmap1, bmap2, 1024)) {
printk("set not equal %d %d\n", start, nbits);
failed_tests++;
}
if (!__bitmap_equal(bmap1, bmap2, 1024)) {
printk("set not __equal %d %d\n", start, nbits);
failed_tests++;
}
bitmap_clear(bmap1, start, nbits);
__bitmap_clear(bmap2, start, nbits);
if (!bitmap_equal(bmap1, bmap2, 1024)) {
printk("clear not equal %d %d\n", start, nbits);
failed_tests++;
}
if (!__bitmap_equal(bmap1, bmap2, 1024)) {
printk("clear not __equal %d %d\n", start,
nbits);
failed_tests++;
}
}
}
}
static const unsigned char clump_exp[] __initconst = {
0x01, /* 1 bit set */
0x02, /* non-edge 1 bit set */
0x00, /* zero bits set */
0x38, /* 3 bits set across 4-bit boundary */
0x38, /* Repeated clump */
0x0F, /* 4 bits set */
0xFF, /* all bits set */
0x05, /* non-adjacent 2 bits set */
};
static void __init test_for_each_set_clump8(void)
{
#define CLUMP_EXP_NUMBITS 64
DECLARE_BITMAP(bits, CLUMP_EXP_NUMBITS);
unsigned int start;
unsigned long clump;
/* set bitmap to test case */
bitmap_zero(bits, CLUMP_EXP_NUMBITS);
bitmap_set(bits, 0, 1); /* 0x01 */
bitmap_set(bits, 9, 1); /* 0x02 */
bitmap_set(bits, 27, 3); /* 0x28 */
bitmap_set(bits, 35, 3); /* 0x28 */
bitmap_set(bits, 40, 4); /* 0x0F */
bitmap_set(bits, 48, 8); /* 0xFF */
bitmap_set(bits, 56, 1); /* 0x05 - part 1 */
bitmap_set(bits, 58, 1); /* 0x05 - part 2 */
for_each_set_clump8(start, clump, bits, CLUMP_EXP_NUMBITS)
expect_eq_clump8(start, CLUMP_EXP_NUMBITS, clump_exp, &clump);
}
static void __init selftest(void)
{
test_zero_clear();
test_fill_set();
test_copy();
test_replace();
test_bitmap_arr32();
test_bitmap_parse();
test_bitmap_parse_user();
test_bitmap_parselist();
test_bitmap_parselist_user();
test_mem_optimisations();
test_for_each_set_clump8();
}
KSTM_MODULE_LOADERS(test_bitmap);
MODULE_AUTHOR("david decotigny <david.decotigny@googlers.com>");
MODULE_LICENSE("GPL");
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