cosmopolitan/test/libc/stdio/rngset_test.c
2022-08-11 12:32:00 -07:00

67 lines
3.2 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2021 Justine Alexandra Roberts Tunney │
│ │
│ Permission to use, copy, modify, and/or distribute this software for │
│ any purpose with or without fee is hereby granted, provided that the │
│ above copyright notice and this permission notice appear in all copies. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/intrin/bits.h"
#include "libc/stdio/rand.h"
#include "libc/testlib/testlib.h"
uint64_t counter(void) {
static uint8_t t;
return 0x0101010101010101ull * t++;
}
TEST(rngset, testZeroReseedInterval_doesntApplyPrng) {
char buf[32];
EXPECT_EQ(buf, rngset(buf, sizeof(buf), counter, 0));
EXPECT_EQ(0x0000000000000000, READ64LE(buf + 0));
EXPECT_EQ(0x0101010101010101, READ64LE(buf + 8));
EXPECT_EQ(0x0202020202020202, READ64LE(buf + 16));
EXPECT_EQ(0x0303030303030303, READ64LE(buf + 24));
}
uint64_t eleet(void) {
return 0x31337;
}
TEST(rngset, testReseedIsNeg_usesInternalVignaPrng) {
char buf[32];
svigna(0x31337);
EXPECT_EQ(buf, rngset(buf, sizeof(buf), eleet, -1));
EXPECT_EQ(vigna(), READ64LE(buf + 0));
EXPECT_EQ(vigna(), READ64LE(buf + 8));
EXPECT_EQ(vigna(), READ64LE(buf + 16));
EXPECT_EQ(vigna(), READ64LE(buf + 24));
}
TEST(rngset, testNullSeedFunction_reseedBecomesVignaSeed) {
char buf[32];
svigna(123);
EXPECT_EQ(buf, rngset(buf, sizeof(buf), 0, 123));
EXPECT_EQ(vigna(), READ64LE(buf + 0));
EXPECT_EQ(vigna(), READ64LE(buf + 8));
EXPECT_EQ(vigna(), READ64LE(buf + 16));
EXPECT_EQ(vigna(), READ64LE(buf + 24));
}
TEST(rngset, testWeirdlyShaped_doesntCrash) {
char buf[7];
rngset(buf, sizeof(buf), 0, 0);
rngset(buf, sizeof(buf), vigna, 0);
rngset(buf, sizeof(buf), vigna, 9);
rngset(buf, sizeof(buf), vigna, 8);
}