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/*
 * Copyright (c) 2015 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.
 */
/*
  Copyright (c) 2001, 2002, 2003 Eliot Dresselhaus

  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 <vppinfra/random.h>

/* Default random seed for standalone version of library.
   Value can be overridden by platform code from e.g.
   machine's clock count register. */
u32 standalone_random_default_seed = 1;

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */
typedef struct { /* Node index of parent. */ u32 parent; /* Node index of first child. */ u32 first_child; /* Next and previous nodes in doubly linked list of siblings. */ u32 next_sibling, prev_sibling; /* Key (distance) for this node. Parent always has key <= than keys of children. */ u32 key; /* Number of children (as opposed to descendents). */ u32 rank; u32 is_marked; /* Set to one when node is inserted; zero when deleted. */ u32 is_valid; } fheap_node_t; #define foreach_fheap_node_sibling(f,ni,first_ni,body) \ do { \ u32 __fheap_foreach_first_ni = (first_ni); \ u32 __fheap_foreach_ni = __fheap_foreach_first_ni; \ u32 __fheap_foreach_next_ni; \ fheap_node_t * __fheap_foreach_n; \ if (__fheap_foreach_ni != ~0) \ while (1) \ { \ __fheap_foreach_n = fheap_get_node ((f), __fheap_foreach_ni); \ __fheap_foreach_next_ni = __fheap_foreach_n -> next_sibling; \ (ni) = __fheap_foreach_ni; \ \ body; \ \ /* End of circular list? */ \ if (__fheap_foreach_next_ni == __fheap_foreach_first_ni) \ break; \ \ __fheap_foreach_ni = __fheap_foreach_next_ni; \ \ } \ } while (0) typedef struct { u32 min_root; /* Vector of nodes. */ fheap_node_t *nodes; u32 *root_list_by_rank; u32 enable_validate; u32 validate_serial; } fheap_t; /* Initialize empty heap. */ always_inline void fheap_init (fheap_t * f, u32 n_nodes) { fheap_node_t *save_nodes = f->nodes; u32 *save_root_list = f->root_list_by_rank; memset (f, 0, sizeof (f[0])); f->nodes = save_nodes; f->root_list_by_rank = save_root_list; vec_validate (f->nodes, n_nodes - 1); vec_reset_length (f->root_list_by_rank); f->min_root = ~0; } always_inline void fheap_free (fheap_t * f) { vec_free (f->nodes); vec_free (f->root_list_by_rank); } always_inline u32 fheap_find_min (fheap_t * f) { return f->min_root; } always_inline u32 fheap_is_empty (fheap_t * f) { return f->min_root == ~0; } /* Add/delete nodes. */ void fheap_add (fheap_t * f, u32 ni, u32 key); void fheap_del (fheap_t * f, u32 ni); /* Delete and return minimum. */ u32 fheap_del_min (fheap_t * f, u32 * min_key); /* Change key value. */ void fheap_decrease_key (fheap_t * f, u32 ni, u32 new_key); #endif /* included_clib_fheap_h */ /* * fd.io coding-style-patch-verification: ON * * Local Variables: * eval: (c-set-style "gnu") * End: */