FD.io VPP  v17.01.1-3-gc6833f8
Vector Packet Processing
cgn_bitmap.h
Go to the documentation of this file.
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  * Modifications to this file
17  * Copyright (c) 2006-2009 by cisco Systems, Inc.
18  * All rights reserved.
19  */
20 
21 /*
22  Copyright (c) 2001, 2002, 2003, 2005 Eliot Dresselhaus
23 
24  Permission is hereby granted, free of charge, to any person obtaining
25  a copy of this software and associated documentation files (the
26  "Software"), to deal in the Software without restriction, including
27  without limitation the rights to use, copy, modify, merge, publish,
28  distribute, sublicense, and/or sell copies of the Software, and to
29  permit persons to whom the Software is furnished to do so, subject to
30  the following conditions:
31 
32  The above copyright notice and this permission notice shall be
33  included in all copies or substantial portions of the Software.
34 
35  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
36  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
37  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
38  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
39  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
40  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
41  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
42 */
43 
44 #ifndef __CGN_BITMAP_H__
45 #define __CGN_BITMAP_H__
46 
47 /* Bitmaps built as vectors of machine words. */
48 
49 #include <string.h>
50 #include <vlib/vlib.h>
51 #include <vnet/vnet.h>
52 #include <vppinfra/vec.h>
53 #include <vppinfra/random.h>
54 
55 #define clib_bitmap_dup(v) vec_dup(v)
56 #define clib_bitmap_free(v) vec_free(v)
57 #define clib_bitmap_bytes(v) vec_bytes(v)
58 #define clib_bitmap_zero(v) vec_zero(v)
59 
60 /* Allocate bitmap with given number of bits. */
61 #define clib_bitmap_alloc(v,n_bits) \
62  v = vec_new (uword, ((n_bits) + BITS (uword) - 1) / BITS (uword))
63 
64 /* Sets given bit. Returns old value. */
65 static inline uword
67 {
68  uword i0 = i / BITS (a[0]);
69  uword bit = (uword) 1 << (i % BITS (a[0]));
70  uword ai;
71 
72 /* ASSERT (i0 < vec_len (a)); */
73  ai = a[i0];
74  a[i0] = ai | bit;
75 
76  return (ai & bit) != 0;
77 }
78 
79 /* Clears given bit. Returns old value. */
80 static inline
82 {
83  uword i0 = i / BITS (a[0]);
84  uword bit = (uword) 1 << (i % BITS (a[0]));
85  uword ai;
86 
87 /* ASSERT (i0 < vec_len (a)); */
88  ai = a[i0];
89  a[i0] = ai & ~bit;
90 
91  return (ai & bit) != 0;
92 }
93 
94 /* Gets num_bits from ai start at start. assume that all bits are
95  * in the same uword.
96  */
97 static inline uword cgn_clib_bitmap_get_bits (uword *ai, u16 start,
98  unsigned char num_bits)
99 {
100  uword i0 = start / BITS (ai[0]);
101  uword i1 = start % BITS (ai[0]);
102  uword result = ai[i0] >> i1;
103  if(num_bits >= BITS(ai[0])) return result;
104  /* Else, we have to trim the bits */
105  result = result & (((uword)1 << num_bits) - 1);
106  return result;
107 }
108 
109 /* Check if all of the bits from start to numb_bits are avaiable */
110 static inline uword cgn_clib_bitmap_check_if_all (uword *ai, u16 start,
111  i16 num_bits)
112 {
113  /* Now check if any bits are zero.. if yes, return false */
114  uword bitmask;
115  if(num_bits >= BITS(ai[0])) {
116  /* assume that its going to be multiples of BUTS(ai[0]) */
117  uword i0 = start / BITS (ai[0]);
118  bitmask = ~0; /* set all bits to 1 */
119  do {
120  if(ai[i0] ^ bitmask) return 0;
121  num_bits = num_bits - BITS (ai[0]);
122  i0++;
123  } while (num_bits > 0);
124  return 1;
125  }
126  else {
127  uword result = cgn_clib_bitmap_get_bits (ai, start, num_bits);
128  bitmask = ((uword)1 << num_bits) -1; /* set only num_bits */
129  return (!(result ^ bitmask));
130  }
131 }
132 
133 #endif
sll srl srl sll sra u16x4 i
Definition: vector_sse2.h:343
a
Definition: bitmap.h:516
static uword cgn_clib_bitmap_get_bits(uword *ai, u16 start, unsigned char num_bits)
Definition: cgn_bitmap.h:97
static uword cgn_clib_bitmap_clear_no_check(uword *a, uword i)
Definition: cgn_bitmap.h:81
u64 uword
Definition: types.h:112
unsigned short u16
Definition: types.h:57
Linear Congruential Random Number Generator.
short i16
Definition: types.h:46
static uword cgn_clib_bitmap_check_if_all(uword *ai, u16 start, i16 num_bits)
Definition: cgn_bitmap.h:110
#define BITS(x)
Definition: clib.h:58
static uword cgn_clib_bitmap_set_no_check(uword *a, uword i)
Definition: cgn_bitmap.h:66
CLIB vectors are ubiquitous dynamically resized arrays with by user defined "headers".