// Copyright 2020 The Pigweed Authors // // Licensed under the Apache License, Version 2.0 (the "License"); you may not // use this file except in compliance with the License. You may obtain a copy of // the License at // // https://www.apache.org/licenses/LICENSE-2.0 // // Unless required by applicable law or agreed to in writing, software // distributed under the License is distributed on an "AS IS" BASIS, WITHOUT // WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the // License for the specific language governing permissions and limitations under // the License. // This tests the C hashing macros and C++ hashing functions. #include "pw_tokenizer/hash.h" #include #include #include "gtest/gtest.h" #include "pw_preprocessor/util.h" #include "pw_tokenizer/internal/pw_tokenizer_65599_fixed_length_128_hash_macro.h" #include "pw_tokenizer/internal/pw_tokenizer_65599_fixed_length_256_hash_macro.h" #include "pw_tokenizer/internal/pw_tokenizer_65599_fixed_length_80_hash_macro.h" #include "pw_tokenizer/internal/pw_tokenizer_65599_fixed_length_96_hash_macro.h" #include "pw_tokenizer_private/generated_hash_test_cases.h" namespace pw::tokenizer { namespace { // Make sure the array test cases file isn't empty. static_assert(PW_ARRAY_SIZE(kHashTests) > 10, "The test cases array is suspiciously small"); constexpr bool CheckGeneratedCases() { for (const auto [string, hash_length, python_hash, macro_hash] : kHashTests) { const uint32_t calculated_hash = PwTokenizer65599FixedLengthHash(string, hash_length); if (calculated_hash != python_hash || calculated_hash != macro_hash) { return false; } } return true; } static_assert(CheckGeneratedCases(), "Hashes in the generated test cases must match"); TEST(Hashing, GeneratedCasesAtRuntime) { for (const auto [string, hash_length, python_hash, macro_hash] : kHashTests) { const uint32_t calculated_hash = PwTokenizer65599FixedLengthHash(string, hash_length); EXPECT_EQ(calculated_hash, python_hash); EXPECT_EQ(calculated_hash, macro_hash); } } // Gets the size of the string, excluding the null terminator. A uint32_t is // used instead of a size_t since the hash calculation requires a uint32_t. template constexpr uint32_t StringLength(const char (&)[kSizeWithNull]) { static_assert(kSizeWithNull > 0u); return kSizeWithNull - 1; // subtract the null terminator } TEST(Hashing, Runtime) PW_NO_SANITIZE("unsigned-integer-overflow") { // Coefficients for the hash terms; k1 is 1. static constexpr uint32_t k2 = k65599HashConstant; static constexpr uint32_t k3 = k65599HashConstant * k2; static constexpr uint32_t k4 = k65599HashConstant * k3; static constexpr uint32_t k5 = k65599HashConstant * k4; // Hash a few things at hash length 4 // The coefficient calculation is done modulo 0x100000000, so the unsigned // integer overflows of the hash terms are intentional. EXPECT_EQ(PwTokenizer65599FixedLengthHash("", 4), StringLength("")); EXPECT_EQ(PwTokenizer65599FixedLengthHash("1", 4), StringLength("1") + k2 * '1'); EXPECT_EQ(PwTokenizer65599FixedLengthHash("12", 4), StringLength("12") + k2 * '1' + k3 * '2'); EXPECT_EQ(PwTokenizer65599FixedLengthHash("123", 4), StringLength("123") + k2 * '1' + k3 * '2' + k4 * '3'); EXPECT_EQ(PwTokenizer65599FixedLengthHash("1234", 4), StringLength("1234") + k2 * '1' + k3 * '2' + k4 * '3' + k5 * '4'); EXPECT_EQ(PwTokenizer65599FixedLengthHash("12345", 4), StringLength("12345") + k2 * '1' + k3 * '2' + k4 * '3' + k5 * '4'); EXPECT_EQ(PwTokenizer65599FixedLengthHash("123456", 4), StringLength("123456") + k2 * '1' + k3 * '2' + k4 * '3' + k5 * '4'); } #define _CHECK_HASH_LENGTH(string, length) \ static_assert(PwTokenizer65599FixedLengthHash( \ std::string_view(string, sizeof(string) - 1), length) == \ PW_TOKENIZER_65599_FIXED_LENGTH_##length##_HASH(string), \ #length "-byte hash mismatch!") // Use std::string_view so that \0 can appear in strings. #define TEST_SUPPORTED_HASHES(string_literal) \ _CHECK_HASH_LENGTH(string_literal, 80); \ _CHECK_HASH_LENGTH(string_literal, 96); \ _CHECK_HASH_LENGTH(string_literal, 128); \ _CHECK_HASH_LENGTH(string_literal, 256); \ static_assert( \ PwTokenizer65599FixedLengthHash( \ std::string_view(string_literal, sizeof(string_literal) - 1), \ sizeof(string_literal) - 1) == Hash(string_literal), \ "Hash function mismatch!"); \ EXPECT_EQ(PwTokenizer65599FixedLengthHash( \ std::string_view(string_literal, sizeof(string_literal) - 1), \ sizeof(string_literal) - 1), \ pw_tokenizer_65599FixedLengthHash(string_literal, \ sizeof(string_literal) - 1, \ sizeof(string_literal) - 1)) TEST(HashMacro, Empty) { TEST_SUPPORTED_HASHES(""); } TEST(HashMacro, NullTerminatorsAreIncludedInHash) { using namespace std::literals; // use an sv literal to include the \0 TEST_SUPPORTED_HASHES("hello\0there"); TEST_SUPPORTED_HASHES("\0"); TEST_SUPPORTED_HASHES("\0\0"); TEST_SUPPORTED_HASHES("\0\0\0"); static_assert( PwTokenizer65599FixedLengthHash(""sv, 80) != PwTokenizer65599FixedLengthHash("\0"sv, 80), "Hashes of \\0 strings should differ since the lengths are included"); static_assert( PwTokenizer65599FixedLengthHash("\0"sv, 80) != PwTokenizer65599FixedLengthHash("\0\0"sv, 80), "Hashes of \\0 strings should differ since the lengths are included"); static_assert( PwTokenizer65599FixedLengthHash("\0\0"sv, 80) != PwTokenizer65599FixedLengthHash("\0\0\0"sv, 80), "Hashes of \\0 strings should differ since the lengths are included"); } TEST(HashMacro, OneChar) { TEST_SUPPORTED_HASHES("a"); TEST_SUPPORTED_HASHES("c"); TEST_SUPPORTED_HASHES("A"); TEST_SUPPORTED_HASHES("B"); TEST_SUPPORTED_HASHES("C"); TEST_SUPPORTED_HASHES("$"); TEST_SUPPORTED_HASHES("%"); TEST_SUPPORTED_HASHES("^"); TEST_SUPPORTED_HASHES("\xa1"); TEST_SUPPORTED_HASHES("\xff"); } TEST(HashMacro, Phrases) { TEST_SUPPORTED_HASHES("WASD"); TEST_SUPPORTED_HASHES("hello, world"); TEST_SUPPORTED_HASHES("Let the wookie win."); TEST_SUPPORTED_HASHES("\x01 more test, just for \xffun"); } TEST(HashMacro, HashesChange) { static_assert(PW_TOKENIZER_65599_FIXED_LENGTH_80_HASH("") != PW_TOKENIZER_65599_FIXED_LENGTH_80_HASH("\0")); static_assert(PW_TOKENIZER_65599_FIXED_LENGTH_80_HASH("a") != PW_TOKENIZER_65599_FIXED_LENGTH_80_HASH("b")); static_assert(PW_TOKENIZER_65599_FIXED_LENGTH_80_HASH("z") != PW_TOKENIZER_65599_FIXED_LENGTH_80_HASH("aa")); static_assert( PW_TOKENIZER_65599_FIXED_LENGTH_80_HASH("make sure hashes change") != PW_TOKENIZER_65599_FIXED_LENGTH_80_HASH("MAKE SURE HASHES CHANGE")); } // Define string literals to test boundary conditions. #define LITERAL_79 \ "0123456789ABCDEF" \ "0123456789ABCDEF" \ "0123456789ABCDEF" \ "0123456789ABCDEF" \ "0123456789ABCDE" #define LITERAL_80 LITERAL_79 "F" #define LITERAL_96 LITERAL_80 "0123456789ABCDEF" #define LITERAL_128 \ LITERAL_96 \ "0123456789ABCDEF" \ "0123456789ABCDEF" static_assert(sizeof(LITERAL_79) - 1 == 79); static_assert(sizeof(LITERAL_80) - 1 == 80); static_assert(sizeof(LITERAL_96) - 1 == 96); static_assert(sizeof(LITERAL_128) - 1 == 128); TEST(HashMacro, HashNearFixedHashLength_80) { // 79, 80, 81, 82 bytes TEST_SUPPORTED_HASHES(LITERAL_79); TEST_SUPPORTED_HASHES(LITERAL_80); TEST_SUPPORTED_HASHES(LITERAL_80 "!"); TEST_SUPPORTED_HASHES(LITERAL_80 "!!"); } TEST(HashMacro, HashNearFixedHashLength_96) { // 95, 96, 97, 98 bytes TEST_SUPPORTED_HASHES(LITERAL_80 "0123456789ABCDE"); TEST_SUPPORTED_HASHES(LITERAL_96); TEST_SUPPORTED_HASHES(LITERAL_96 "!"); TEST_SUPPORTED_HASHES(LITERAL_96 "XY"); } TEST(HashMacro, HashNearFixedHashLength_128) { // 127, 128, 129, 130 bytes TEST_SUPPORTED_HASHES(LITERAL_96 "0123456789ABCDEF" "0123456789ABCDE"); TEST_SUPPORTED_HASHES(LITERAL_128); TEST_SUPPORTED_HASHES(LITERAL_128 "!"); TEST_SUPPORTED_HASHES(LITERAL_128 "AB"); } TEST(HashMacro, HashVeryLongStrings) { TEST_SUPPORTED_HASHES( "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"); TEST_SUPPORTED_HASHES(LITERAL_128 LITERAL_128 LITERAL_128); } TEST(HashMacro, ExtraCharactersAreIgnored) { static_assert(PW_TOKENIZER_65599_FIXED_LENGTH_80_HASH(LITERAL_80 "?") == PW_TOKENIZER_65599_FIXED_LENGTH_80_HASH(LITERAL_80 ".")); static_assert(PW_TOKENIZER_65599_FIXED_LENGTH_80_HASH(LITERAL_80 "ABCD") == PW_TOKENIZER_65599_FIXED_LENGTH_80_HASH(LITERAL_80 "zyxw")); static_assert(PW_TOKENIZER_65599_FIXED_LENGTH_96_HASH(LITERAL_96 "?") == PW_TOKENIZER_65599_FIXED_LENGTH_96_HASH(LITERAL_96 ".")); static_assert(PW_TOKENIZER_65599_FIXED_LENGTH_96_HASH(LITERAL_96 "ABCD") == PW_TOKENIZER_65599_FIXED_LENGTH_96_HASH(LITERAL_96 "zyxw")); static_assert(PW_TOKENIZER_65599_FIXED_LENGTH_128_HASH(LITERAL_128 "?") == PW_TOKENIZER_65599_FIXED_LENGTH_128_HASH(LITERAL_128 ".")); static_assert(PW_TOKENIZER_65599_FIXED_LENGTH_128_HASH(LITERAL_128 "ABCD") == PW_TOKENIZER_65599_FIXED_LENGTH_128_HASH(LITERAL_128 "zyxw")); } } // namespace } // namespace pw::tokenizer