FD.io VPP  v19.04-6-g6f05f72
Vector Packet Processing
random_buffer.c
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1 /*
2  * Copyright (c) 2015 Cisco and/or its affiliates.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at:
6  *
7  * http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 /*
16  Copyright (c) 2005 Eliot Dresselhaus
17 
18  Permission is hereby granted, free of charge, to any person obtaining
19  a copy of this software and associated documentation files (the
20  "Software"), to deal in the Software without restriction, including
21  without limitation the rights to use, copy, modify, merge, publish,
22  distribute, sublicense, and/or sell copies of the Software, and to
23  permit persons to whom the Software is furnished to do so, subject to
24  the following conditions:
25 
26  The above copyright notice and this permission notice shall be
27  included in all copies or substantial portions of the Software.
28 
29  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
30  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
31  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
32  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
33  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
34  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
35  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
36 */
37 
38 #include <vppinfra/random_buffer.h>
39 
40 /* Fill random buffer. */
41 void
43 {
44  uword *w, n = n_words;
45 
46  if (n < 256)
47  n = 256;
48 
49  n = round_pow2 (n, 2 << ISAAC_LOG2_SIZE);
50 
51  vec_add2 (b->buffer, w, n);
52  do
53  {
54  isaac2 (b->ctx, w);
55  w += 2 * ISAAC_SIZE;
56  n -= 2 * ISAAC_SIZE;
57  }
58  while (n > 0);
59 }
60 
61 void
63 {
64  uword i, j;
65 
66  clib_memset (b, 0, sizeof (b[0]));
67 
68  /* Seed ISAAC. */
69  for (i = 0; i < ARRAY_LEN (b->ctx); i++)
70  {
71  uword s[ISAAC_SIZE];
72 
73  for (j = 0; j < ARRAY_LEN (s); j++)
74  s[j] = ARRAY_LEN (b->ctx) * (seed + j) + i;
75 
76  isaac_init (&b->ctx[i], s);
77  }
78 }
79 
80 /*
81  * fd.io coding-style-patch-verification: ON
82  *
83  * Local Variables:
84  * eval: (c-set-style "gnu")
85  * End:
86  */
void isaac_init(isaac_t *ctx, uword *results)
void clib_random_buffer_init(clib_random_buffer_t *b, uword seed)
Definition: random_buffer.c:62
#define vec_add2(V, P, N)
Add N elements to end of vector V, return pointer to new elements in P.
Definition: vec.h:560
int i
clib_memset(h->entries, 0, sizeof(h->entries[0])*entries)
void clib_random_buffer_fill(clib_random_buffer_t *b, uword n_words)
Definition: random_buffer.c:42
void isaac2(isaac_t *ctx, uword *results)
#define ISAAC_LOG2_SIZE
Definition: random_isaac.h:58
#define ARRAY_LEN(x)
Definition: clib.h:62
static uword round_pow2(uword x, uword pow2)
Definition: clib.h:241
#define ISAAC_SIZE
Definition: random_isaac.h:59
u64 uword
Definition: types.h:112