FD.io VPP  v19.01.3-6-g70449b9b9
Vector Packet Processing
vec_bootstrap.h
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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.
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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
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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 
55 typedef 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 
80 vec_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 
92 always_inline void *
93 vec_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 
104 always_inline void *
105 vec_header_end (void *v, uword header_bytes)
106 {
107  return v + vec_header_bytes (header_bytes);
108 }
109 
111 vec_aligned_header_bytes (uword header_bytes, uword align)
112 {
113  return round_pow2 (header_bytes + sizeof (vec_header_t), align);
114 }
115 
116 always_inline void *
117 vec_aligned_header (void *v, uword header_bytes, uword align)
118 {
119  return v - vec_aligned_header_bytes (header_bytes, align);
120 }
121 
122 always_inline void *
123 vec_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 Reset vector length to zero
146  NULL-pointer tolerant
147 */
148 
149 #define vec_reset_length(v) do { if (v) _vec_len (v) = 0; } while (0)
150 
151 /** \brief Number of data bytes in vector. */
152 
153 #define vec_bytes(v) (vec_len (v) * sizeof (v[0]))
154 
155 /** \brief Total number of bytes that can fit in vector with current allocation. */
156 
157 #define vec_capacity(v,b) \
158 ({ \
159  void * _vec_capacity_v = (void *) (v); \
160  uword _vec_capacity_b = (b); \
161  _vec_capacity_b = sizeof (vec_header_t) + _vec_round_size (_vec_capacity_b); \
162  _vec_capacity_v ? clib_mem_size (_vec_capacity_v - _vec_capacity_b) : 0; \
163 })
164 
165 /** \brief Total number of elements that can fit into vector. */
166 #define vec_max_len(v) (vec_capacity(v,0) / sizeof (v[0]))
167 
168 /** \brief End (last data address) of vector. */
169 #define vec_end(v) ((v) + vec_len (v))
170 
171 /** \brief True if given pointer is within given vector. */
172 #define vec_is_member(v,e) ((e) >= (v) && (e) < vec_end (v))
173 
174 /** \brief Get vector value at index i checking that i is in bounds. */
175 #define vec_elt_at_index(v,i) \
176 ({ \
177  ASSERT ((i) < vec_len (v)); \
178  (v) + (i); \
179 })
180 
181 /** \brief Get vector value at index i */
182 #define vec_elt(v,i) (vec_elt_at_index(v,i))[0]
183 
184 /** \brief Vector iterator */
185 #define vec_foreach(var,vec) for (var = (vec); var < vec_end (vec); var++)
186 
187 /** \brief Vector iterator (reverse) */
188 #define vec_foreach_backwards(var,vec) \
189 for (var = vec_end (vec) - 1; var >= (vec); var--)
190 
191 /** \brief Iterate over vector indices. */
192 #define vec_foreach_index(var,v) for ((var) = 0; (var) < vec_len (v); (var)++)
193 
194 /** \brief Iterate over vector indices (reverse). */
195 #define vec_foreach_index_backwards(var,v) \
196  for ((var) = vec_len((v)) - 1; (var) >= 0; (var)--)
197 
198 #endif /* included_clib_vec_bootstrap_h */
199 
200 /*
201  * fd.io coding-style-patch-verification: ON
202  *
203  * Local Variables:
204  * eval: (c-set-style "gnu")
205  * End:
206  */
unsigned long u64
Definition: types.h:89
unsigned char u8
Definition: types.h:56
static uword vec_header_bytes(uword header_bytes)
Definition: vec_bootstrap.h:80
u32 dlmalloc_header_offset
offset to memory allocator offset
Definition: vec_bootstrap.h:61
#define always_inline
Definition: clib.h:98
unsigned int u32
Definition: types.h:88
static uword vec_aligned_header_bytes(uword header_bytes, uword align)
u8 len
Definition: ip_types.api:49
static void * vec_aligned_header(void *v, uword header_bytes, uword align)
static uword round_pow2(uword x, uword pow2)
Definition: clib.h:241
u32 len
Number of elements in vector (NOT its allocated length).
Definition: vec_bootstrap.h:60
vector header structure
Definition: vec_bootstrap.h:55
u64 uword
Definition: types.h:112
static void * vec_aligned_header_end(void *v, uword header_bytes, uword align)
static void * vec_header(void *v, uword header_bytes)
Find a user vector header.
Definition: vec_bootstrap.h:93
static void * vec_header_end(void *v, uword header_bytes)
Find the end of user vector header.