vec_bootstrap.h revision 9fb6d40e
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) 2001, 2002, 2003 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#ifndef included_clib_vec_bootstrap_h
39#define included_clib_vec_bootstrap_h
40
41/** \file
42    Vector bootstrap header file
43*/
44
45/* Bootstrap include so that #include <vppinfra/mem.h> can include e.g.
46   <vppinfra/mheap.h> which depends on <vppinfra/vec.h>. */
47
48/** \brief vector header structure
49
50   Bookkeeping header preceding vector elements in memory.
51   User header information may preceed standard vec header.
52   If you change u32 len -> u64 len, single vectors can
53   exceed 2**32 elements. Clib heaps are vectors. */
54
55typedef struct
56{
57#if CLIB_VEC64 > 0
58  u64 len;
59#else
60  u32 len; /**< Number of elements in vector (NOT its allocated length). */
61  u32 dlmalloc_header_offset;	/**< offset to memory allocator offset  */
62#endif
63  u8 vector_data[0];  /**< Vector data . */
64} vec_header_t;
65
66/** \brief Find the vector header
67
68    Given the user's pointer to a vector, find the corresponding
69    vector header
70
71    @param v pointer to a vector
72    @return pointer to the vector's vector_header_t
73*/
74#define _vec_find(v)	((vec_header_t *) (v) - 1)
75
76#define _vec_round_size(s) \
77  (((s) + sizeof (uword) - 1) &~ (sizeof (uword) - 1))
78
79always_inline uword
80vec_header_bytes (uword header_bytes)
81{
82  return round_pow2 (header_bytes + sizeof (vec_header_t),
83		     sizeof (vec_header_t));
84}
85
86/** \brief Find a user vector header
87
88    Finds the user header of a vector with unspecified alignment given
89    the user pointer to the vector.
90*/
91
92always_inline void *
93vec_header (void *v, uword header_bytes)
94{
95  return v - vec_header_bytes (header_bytes);
96}
97
98/** \brief Find the end of user vector header
99
100    Finds the end of the user header of a vector with unspecified
101    alignment given the user pointer to the vector.
102*/
103
104always_inline void *
105vec_header_end (void *v, uword header_bytes)
106{
107  return v + vec_header_bytes (header_bytes);
108}
109
110always_inline uword
111vec_aligned_header_bytes (uword header_bytes, uword align)
112{
113  return round_pow2 (header_bytes + sizeof (vec_header_t), align);
114}
115
116always_inline void *
117vec_aligned_header (void *v, uword header_bytes, uword align)
118{
119  return v - vec_aligned_header_bytes (header_bytes, align);
120}
121
122always_inline void *
123vec_aligned_header_end (void *v, uword header_bytes, uword align)
124{
125  return v + vec_aligned_header_bytes (header_bytes, align);
126}
127
128
129/** \brief Number of elements in vector (lvalue-capable)
130
131   _vec_len (v) does not check for null, but can be used as a lvalue
132   (e.g. _vec_len (v) = 99).
133*/
134
135#define _vec_len(v)	(_vec_find(v)->len)
136
137/** \brief Number of elements in vector (rvalue-only, NULL tolerant)
138
139    vec_len (v) checks for NULL, but cannot be used as an lvalue.
140    If in doubt, use vec_len...
141*/
142
143#define vec_len(v)	((v) ? _vec_len(v) : 0)
144
145/** \brief Number of data bytes in vector. */
146
147#define vec_bytes(v) (vec_len (v) * sizeof (v[0]))
148
149/** \brief Total number of bytes that can fit in vector with current allocation. */
150
151#define vec_capacity(v,b)							\
152({										\
153  void * _vec_capacity_v = (void *) (v);					\
154  uword _vec_capacity_b = (b);							\
155  _vec_capacity_b = sizeof (vec_header_t) + _vec_round_size (_vec_capacity_b);	\
156  _vec_capacity_v ? clib_mem_size (_vec_capacity_v - _vec_capacity_b) : 0;	\
157})
158
159/** \brief Total number of elements that can fit into vector. */
160#define vec_max_len(v) (vec_capacity(v,0) / sizeof (v[0]))
161
162/** \brief Set vector length to a user-defined value */
163#ifndef __COVERITY__		/* Coverity gets confused by ASSERT() */
164#define vec_set_len(v, l) do {     \
165    ASSERT(v);                     \
166    ASSERT((l) <= vec_max_len(v)); \
167    CLIB_MEM_POISON_LEN((void *)(v), _vec_len(v) * sizeof((v)[0]), (l) * sizeof((v)[0])); \
168    _vec_len(v) = (l);             \
169} while (0)
170#else /* __COVERITY__ */
171#define vec_set_len(v, l) do {     \
172    _vec_len(v) = (l);             \
173} while (0)
174#endif /* __COVERITY__ */
175
176/** \brief Reset vector length to zero
177    NULL-pointer tolerant
178*/
179#define vec_reset_length(v) do { if (v) vec_set_len (v, 0); } while (0)
180
181/** \brief End (last data address) of vector. */
182#define vec_end(v)	((v) + vec_len (v))
183
184/** \brief True if given pointer is within given vector. */
185#define vec_is_member(v,e) ((e) >= (v) && (e) < vec_end (v))
186
187/** \brief Get vector value at index i checking that i is in bounds. */
188#define vec_elt_at_index(v,i)			\
189({						\
190  ASSERT ((i) < vec_len (v));			\
191  (v) + (i);					\
192})
193
194/** \brief Get vector value at index i */
195#define vec_elt(v,i) (vec_elt_at_index(v,i))[0]
196
197/** \brief Vector iterator */
198#define vec_foreach(var,vec) for (var = (vec); var < vec_end (vec); var++)
199
200/** \brief Vector iterator (reverse) */
201#define vec_foreach_backwards(var,vec) \
202for (var = vec_end (vec) - 1; var >= (vec); var--)
203
204/** \brief Iterate over vector indices. */
205#define vec_foreach_index(var,v) for ((var) = 0; (var) < vec_len (v); (var)++)
206
207/** \brief Iterate over vector indices (reverse). */
208#define vec_foreach_index_backwards(var,v) \
209  for ((var) = vec_len((v)) - 1; (var) >= 0; (var)--)
210
211#endif /* included_clib_vec_bootstrap_h */
212
213/*
214 * fd.io coding-style-patch-verification: ON
215 *
216 * Local Variables:
217 * eval: (c-set-style "gnu")
218 * End:
219 */
220