/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│ │ vi: set et ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi │ ╞══════════════════════════════════════════════════════════════════════════════╡ │ Copyright 2020 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/mem/mem.h" #include "libc/intrin/likely.h" #include "libc/mem/alg.h" #include "libc/stdio/rand.h" #include "libc/str/str.h" #include "libc/testlib/ezbench.h" #include "libc/testlib/hyperion.h" #include "libc/testlib/testlib.h" #define MakeMemory(SL) memcpy(malloc(sizeof(SL) - 1), SL, sizeof(SL) - 1) void *memmem_naive(const void *haystk, size_t haystklen, // const void *needle, size_t needlelen) { size_t i, j; if (!needlelen) return (void *)haystk; if (needlelen > haystklen) return 0; for (i = 0; i < haystklen; ++i) { for (j = 0;; ++j) { if (j == needlelen) return (/*unconst*/ char *)haystk + i; if (i + j == haystklen) break; if (((char *)haystk)[i + j] != ((char *)needle)[j]) break; } } return 0; } TEST(memmem, special) { EXPECT_EQ(0, memmem(0, 0, 0, 0)); EXPECT_EQ(0, memmem(0, 0, "", 1)); EXPECT_EQ("", memmem("", 1, 0, 0)); } TEST(memmem, test) { char *needle = MakeMemory("abcdefgh"); char *haystk = MakeMemory("acccccccbbbbbbbbabcdefghdddddddd"); EXPECT_BINEQ(u"abcdefghdddddddd", memmem(haystk, 32, needle, 8)); memcpy(needle, "aaaaaaaa", 8); memcpy(haystk, "acccccccbbbbbbbbaaaaaaaadddddddd", 32); EXPECT_BINEQ(u"aaaaaaaadddddddd", memmem(haystk, 32, needle, 8)); free(haystk); free(needle); } TEST(memmem, testNoMatch) { char *needle = MakeMemory("abcdefzh"); char *haystk = MakeMemory("acccccccbbbbbbbbabcdefghdddddddd"); EXPECT_EQ(NULL, memmem(haystk, 32, needle, 8)); free(haystk); free(needle); } TEST(memmem, testStartOfMemory) { char *needle = MakeMemory("acccc"); char *haystk = MakeMemory("acccccccbbbbbbbbabcdefghdddddddd"); EXPECT_EQ(&haystk[0], memmem(haystk, 32, needle, 5)); free(haystk); free(needle); } TEST(memmem, testEndOfMemory) { char *haystk = MakeMemory("abc123"); char *needle = MakeMemory("123"); EXPECT_EQ(&haystk[3], memmem(haystk, 6, needle, 3)); free(haystk); free(needle); } TEST(memmem, testOneNo) { char *needle = MakeMemory("z"); char *haystk = MakeMemory("abc123"); EXPECT_EQ(0, memmem(haystk, 6, needle, 1)); free(haystk); free(needle); } TEST(memmem, testOneYes) { char *needle = MakeMemory("3"); char *haystk = MakeMemory("abc123"); EXPECT_EQ(&haystk[5], memmem(haystk, 6, needle, 1)); free(haystk); free(needle); } TEST(memmem, testCrossesSseRegister) { char *haystk = MakeMemory("eeeeeeeeeeeeeeeeffffffffffffffffrrrrrrrrrrrrrrrr"); char *needle = MakeMemory("eeeeeeeeeeeeefffffffffffff"); EXPECT_EQ(&haystk[3], memmem(haystk, 16 * 3, needle, 26)); free(haystk); free(needle); } TEST(memmem, testHasNulCharacters) { char *needle = MakeMemory("eeeeeeeeeeeee\0ffffffffffff"); char *haystk = MakeMemory("eeeeeeeeeeeeeeee\0fffffffffffffffrrrrrrrrrrrrrrrr"); EXPECT_EQ(&haystk[3], memmem(haystk, 16 * 3, needle, 26)); free(haystk); free(needle); } TEST(memmem, testWeird) { char *needle = MakeMemory("-*-+-+-+-+-+-+-+"); char *haystk = MakeMemory("-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-+"); EXPECT_EQ(14, (intptr_t)memmem(haystk, 32, needle, 16) - (intptr_t)haystk); free(haystk); free(needle); } TEST(memmem, testEmptyNeedle_matchesStartOfHaystack) { char *needle = malloc(0); char *haystk = MakeMemory("-+-+-+-+-+-+-+-*-+-+-+-+-+-+-+-+"); EXPECT_EQ(0, (intptr_t)memmem(haystk, 32, needle, 0) - (intptr_t)haystk); free(haystk); free(needle); } TEST(memmem, testEmptyHaystack_alwaysReturnsNull) { char *needle = MakeMemory("-*-+-+-+-+-+-+-+"); char *haystk = malloc(0); EXPECT_EQ(NULL, memmem(haystk, 0, needle, 16)); EXPECT_EQ(NULL, memmem(haystk, 0, needle, 1)); free(haystk); free(needle); } TEST(memmem, testEmptyHaystackAndNeedle_returnsHaystack) { char *needle = malloc(0); char *haystk = malloc(0); EXPECT_EQ(haystk, memmem(haystk, 0, needle, 0)); free(haystk); free(needle); } TEST(memmem, testWut) { ASSERT_STREQ("x", memmem("x", 1, "x", 1)); } TEST(memmem, fuzz) { int i, n, m; char a[128], b[128], *p, *q; for (i = 0; i < 10000; ++i) { rngset(a, sizeof(a), lemur64, -1); rngset(b, sizeof(b), lemur64, -1); p = a + lemur64() % sizeof(a) / 2; q = b + lemur64() % sizeof(b) / 2; n = lemur64() % sizeof(a) / 2; m = lemur64() % sizeof(b) / 2; ASSERT_EQ(memmem_naive(p, n, q, m), memmem(p, n, q, m)); } } /* * memmem naive l: 43,783c 14,142ns m: 31,285c 10,105ns * memmem l: 2,597c 839ns m: 2,612c 844ns * memmem l: 509c 164ns m: 599c 193ns * * strstr naive l: 103,057c 33,287ns m: 47,035c 15,192ns * strstr l: 3,186c 1,029ns m: 3,218c 1,039ns * strstr torture 1 l: 27c 9ns m: 61c 20ns * strstr torture 2 l: 2,322c 750ns m: 2,362c 763ns * strstr torture 4 l: 2,407c 777ns m: 2,448c 791ns * strstr torture 8 l: 2,803c 905ns m: 2,862c 924ns * strstr torture 16 l: 4,559c 1,473ns m: 3,614c 1,167ns * strstr torture 32 l: 5,324c 1,720ns m: 5,577c 1,801ns * * strcasestr naive l: 129,908c 41,959ns m: 155,420c 50,200ns * strcasestr l: 33,464c 10,809ns m: 31,636c 10,218ns * strcasestr tort 1 l: 38c 12ns m: 69c 22ns * strcasestr tort 2 l: 2,544c 822ns m: 2,580c 833ns * strcasestr tort 4 l: 2,745c 887ns m: 2,767c 894ns * strcasestr tort 8 l: 4,198c 1,356ns m: 4,216c 1,362ns * strcasestr tort 16 l: 7,402c 2,391ns m: 7,487c 2,418ns * strcasestr tort 32 l: 13,772c 4,448ns m: 12,945c 4,181ns */ BENCH(memmem, bench) { EZBENCH2("memmem naive", donothing, __expropriate(memmem_naive(kHyperion, kHyperionSize, "THE END", 7))); EZBENCH2("memmem", donothing, __expropriate(memmem(kHyperion, kHyperionSize, "THE END", 7))); EZBENCH2("memmem", donothing, __expropriate(memmem( "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaab", 62, "aaaaaab", 7))); }