bihash_vec8_8.h

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/*
 * Copyright (c) 2017 Cisco and/or its affiliates.
 * 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:
 *
 *     http://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.
 */
#undef BIHASH_TYPE
#undef BIHASH_KVP_PER_PAGE

#define BIHASH_TYPE _vec8_8
#define BIHASH_KVP_PER_PAGE 4

#ifndef __included_bihash_vec8_8_h__
#define __included_bihash_vec8_8_h__

#include <vppinfra/heap.h>
#include <vppinfra/format.h>
#include <vppinfra/pool.h>
#include <vppinfra/xxhash.h>
#include <vppinfra/crc32.h>

/** 8 octet key, 8 octet key value pair */
typedef struct
{
  u64 key;                      /**< the key */
  u64 value;                    /**< the value */
} clib_bihash_kv_vec8_8_t;

/** Decide if a clib_bihash_kv_vec8_8_t instance is free
    @param v- pointer to the (key,value) pair
*/
static inline int
clib_bihash_is_free_vec8_8 (clib_bihash_kv_vec8_8_t * v)
{
  if (v->key == ~0ULL && v->value == ~0ULL)
    return 1;
  return 0;
}

/** Hash a clib_bihash_kv_vec8_8_t instance
    @param v - pointer to the (key,value) pair, hash the key (only)
*/
static inline u64
clib_bihash_hash_vec8_8 (clib_bihash_kv_vec8_8_t * v)
{
  u8 *keyp = (u8 *) (v->key);
  /* Note: to torture-test linear scan, make this fn return a constant */
#ifdef clib_crc32c_uses_intrinsics
  return clib_crc32c (keyp, vec_len (keyp));
#else
  {
    int i, j;
    u64 sum = 0;

    for (i = 0, j = 0; i < vec_len (keyp); i++)
      {
        sum ^= keyp[i] << (j * 8);
        j++;
        if (j == 4)
          j = 0;
      }

    return clib_xxhash (sum);
  }
#endif
}

/** Format a clib_bihash_kv_vec8_8_t instance
    @param s - u8 * vector under construction
    @param args (vararg) - the (key,value) pair to format
    @return s - the u8 * vector under construction
*/
static inline u8 *
format_bihash_kvp_vec8_8 (u8 * s, va_list * args)
{
  clib_bihash_kv_vec8_8_t *v = va_arg (*args, clib_bihash_kv_vec8_8_t *);

  s = format (s, "key %U value %llu",
              format_hex_bytes, v->key, vec_len ((u8 *) (v->key)), v->value);
  return s;
}

/** Compare two clib_bihash_kv_vec8_8_t instances
    @param a - first key
    @param b - second key
*/
static inline int
clib_bihash_key_compare_vec8_8 (u64 a_arg, u64 b_arg)
{
  u8 *a = (u8 *) a_arg;
  u8 *b = (u8 *) b_arg;

  if (a_arg == ~0ULL || b_arg == ~0ULL)
    return 0;

  if (vec_len (a) != vec_len (b))
    return 0;

  return memcmp (a, b, vec_len (a)) == 0;
}

#undef __included_bihash_template_h__
#include <vppinfra/bihash_template.h>

#endif /* __included_bihash_vec8_8_h__ */

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */