/*
 * This file is based on code that is part of SMHasher
 * (https://code.google.com/p/smhasher/), and is subject to the MIT license
 * (http://www.opensource.org/licenses/mit-license.php).  Both email addresses
 * associated with the source code's revision history belong to Austin Appleby,
 * and the revision history ranges from 2010 to 2012.  Therefore the copyright
 * and license are here taken to be:
 *
 * Copyright (c) 2010-2012 Austin Appleby
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include "test/jemalloc_test.h"

typedef enum {
	hash_variant_x86_32,
	hash_variant_x86_128,
	hash_variant_x64_128
} hash_variant_t;

static size_t
hash_variant_bits(hash_variant_t variant)
{

	switch (variant) {
	case hash_variant_x86_32: return (32);
	case hash_variant_x86_128: return (128);
	case hash_variant_x64_128: return (128);
	default: not_reached();
	}
}

static const char *
hash_variant_string(hash_variant_t variant)
{

	switch (variant) {
	case hash_variant_x86_32: return ("hash_x86_32");
	case hash_variant_x86_128: return ("hash_x86_128");
	case hash_variant_x64_128: return ("hash_x64_128");
	default: not_reached();
	}
}

static void
hash_variant_verify(hash_variant_t variant)
{
	const size_t hashbytes = hash_variant_bits(variant) / 8;
	uint8_t key[256];
	uint8_t hashes[hashbytes * 256];
	uint8_t final[hashbytes];
	unsigned i;
	uint32_t computed, expected;

	memset(key, 0, sizeof(key));
	memset(hashes, 0, sizeof(hashes));
	memset(final, 0, sizeof(final));

	/*
	 * Hash keys of the form {0}, {0,1}, {0,1,2}, ..., {0,1,...,255} as the
	 * seed.
	 */
	for (i = 0; i < 256; i++) {
		key[i] = (uint8_t)i;
		switch (variant) {
		case hash_variant_x86_32: {
			uint32_t out;
			out = hash_x86_32(key, i, 256-i);
			memcpy(&hashes[i*hashbytes], &out, hashbytes);
			break;
		} case hash_variant_x86_128: {
			uint64_t out[2];
			hash_x86_128(key, i, 256-i, out);
			memcpy(&hashes[i*hashbytes], out, hashbytes);
			break;
		} case hash_variant_x64_128: {
			uint64_t out[2];
			hash_x64_128(key, i, 256-i, out);
			memcpy(&hashes[i*hashbytes], out, hashbytes);
			break;
		} default: not_reached();
		}
	}

	/* Hash the result array. */
	switch (variant) {
	case hash_variant_x86_32: {
		uint32_t out = hash_x86_32(hashes, hashbytes*256, 0);
		memcpy(final, &out, sizeof(out));
		break;
	} case hash_variant_x86_128: {
		uint64_t out[2];
		hash_x86_128(hashes, hashbytes*256, 0, out);
		memcpy(final, out, sizeof(out));
		break;
	} case hash_variant_x64_128: {
		uint64_t out[2];
		hash_x64_128(hashes, hashbytes*256, 0, out);
		memcpy(final, out, sizeof(out));
		break;
	} default: not_reached();
	}

	computed = (final[0] << 0) | (final[1] << 8) | (final[2] << 16) |
	    (final[3] << 24);

	switch (variant) {
#ifdef JEMALLOC_BIG_ENDIAN
	case hash_variant_x86_32: expected = 0x6213303eU; break;
	case hash_variant_x86_128: expected = 0x266820caU; break;
	case hash_variant_x64_128: expected = 0xcc622b6fU; break;
#else
	case hash_variant_x86_32: expected = 0xb0f57ee3U; break;
	case hash_variant_x86_128: expected = 0xb3ece62aU; break;
	case hash_variant_x64_128: expected = 0x6384ba69U; break;
#endif
	default: not_reached();
	}

	assert_u32_eq(computed, expected,
	    "Hash mismatch for %s(): expected %#x but got %#x",
	    hash_variant_string(variant), expected, computed);
}

TEST_BEGIN(test_hash_x86_32)
{

	hash_variant_verify(hash_variant_x86_32);
}
TEST_END

TEST_BEGIN(test_hash_x86_128)
{

	hash_variant_verify(hash_variant_x86_128);
}
TEST_END

TEST_BEGIN(test_hash_x64_128)
{

	hash_variant_verify(hash_variant_x64_128);
}
TEST_END

int
main(void)
{

	return (test(
	    test_hash_x86_32,
	    test_hash_x86_128,
	    test_hash_x64_128));
}
