#include "compress.h"

#include "macro.h"

#include "parse-util.h"

#include "random-util.h"

#include "string-util.h"

#include "util.h"

typedef int (compress_t)(const void *src, uint64_t src_size, void *dst, size_t *dst_size);

typedef int (decompress_t)(const void *src, uint64_t src_size,

void **dst, size_t *dst_alloc_size, size_t* dst_size, size_t dst_max);

static usec_t arg_duration = 2 * USEC_PER_SEC;

static size_t arg_start;

#define MAX_SIZE (1024*1024LU)

#define PRIME 1048571 /* A prime close enough to one megabyte that mod 4 == 3 */

static size_t _permute(size_t x) {

size_t residue;

if (x >= PRIME)

return x;

residue = x*x % PRIME;

if (x <= PRIME / 2)

return residue;

else

return PRIME - residue;

}

static size_t permute(size_t x) {

return _permute((_permute(x) + arg_start) % MAX_SIZE ^ 0xFF345);

}

static char* make_buf(size_t count, const char *type) {

char *buf;

size_t i;

buf = malloc(count);

assert_se(buf);

if (streq(type, "zeros"))

memzero(buf, count);

else if (streq(type, "simple"))

for (i = 0; i < count; i++)

buf[i] = 'a' + i % ('z' - 'a' + 1);

else if (streq(type, "random")) {

size_t step = count / 10;

random_bytes(buf, step);

memzero(buf + 1*step, step);

random_bytes(buf + 2*step, step);

memzero(buf + 3*step, step);

random_bytes(buf + 4*step, step);

memzero(buf + 5*step, step);

random_bytes(buf + 6*step, step);

memzero(buf + 7*step, step);

random_bytes(buf + 8*step, step);

memzero(buf + 9*step, step);

} else

assert_not_reached("here");

return buf;

}

static void test_compress_decompress(const char* label, const char* type,

compress_t compress, decompress_t decompress) {

usec_t n, n2 = 0;

float dt;

_cleanup_free_ char *text, *buf;

_cleanup_free_ void *buf2 = NULL;

size_t buf2_allocated = 0;

size_t skipped = 0, compressed = 0, total = 0;

text = make_buf(MAX_SIZE, type);

buf = calloc(MAX_SIZE + 1, 1);

assert_se(text && buf);

n = now(CLOCK_MONOTONIC);

for (size_t i = 0; i <= MAX_SIZE; i++) {

size_t j = 0, k = 0, size;

int r;

size = permute(i);

log_debug("%s %zu %zu", type, i, size);

memzero(buf, MIN(size + 1000, MAX_SIZE));

r = compress(text, size, buf, &j);

/* assume compression must be successful except for small inputs */

assert_se(r == 0 || (size < 2048 && r == -ENOBUFS) || streq(type, "random"));

/* check for overwrites */

assert_se(buf[size] == 0);

if (r != 0) {

skipped += size;

continue;

}

assert_se(j > 0);

if (j >= size)

log_error("%s \"compressed\" %zu -> %zu", label, size, j);

r = decompress(buf, j, &buf2, &buf2_allocated, &k, 0);

assert_se(r == 0);

assert_se(buf2_allocated >= k);

assert_se(k == size);

assert_se(memcmp(text, buf2, size) == 0);

total += size;

compressed += j;

n2 = now(CLOCK_MONOTONIC);

if (n2 - n > arg_duration)

break;

}

dt = (n2-n) / 1e6;

log_info("%s/%s: compressed & decompressed %zu bytes in %.2fs (%.2fMiB/s), "

"mean compresion %.2f%%, skipped %zu bytes",

label, type, total, dt,

total / 1024. / 1024 / dt,

100 - compressed * 100. / total,

skipped);

}

int main(int argc, char *argv[]) {

const char *i;

log_set_max_level(LOG_INFO);

if (argc >= 2) {

unsigned x;

assert_se(safe_atou(argv[1], &x) >= 0);

arg_duration = x * USEC_PER_SEC;

}

if (argc == 3)

(void) safe_atolu(argv[2], &arg_start);

else

arg_start = getpid();

NULSTR_FOREACH(i, "zeros\0simple\0random\0") {

#ifdef HAVE_XZ

test_compress_decompress("XZ", i, compress_blob_xz, decompress_blob_xz);

#endif

#ifdef HAVE_LZ4

test_compress_decompress("LZ4", i, compress_blob_lz4, decompress_blob_lz4);

#endif

}

return 0;

}