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:
7 * http://www.apache.org/licenses/LICENSE-2.0
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.
16 Copyright (c) 2001-2005 Eliot Dresselhaus
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:
26 The above copyright notice and this permission notice shall be
27 included in all copies or substantial portions of the Software.
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.
38 #ifndef included_hash_h
39 #define included_hash_h
41 #include <vppinfra/error.h>
42 #include <vppinfra/format.h>
43 #include <vppinfra/vec.h>
44 #include <vppinfra/vector.h>
48 typedef uword (hash_key_sum_function_t) (struct hash_header *, uword key);
49 typedef uword (hash_key_equal_function_t)
50 (struct hash_header *, uword key1, uword key2);
52 /* Vector header for hash tables. */
53 typedef struct hash_header
55 /* Number of elements in hash table. */
58 /* Flags as follows. */
61 /* Set if user does not want table to auto-resize when sufficiently full. */
62 #define HASH_FLAG_NO_AUTO_GROW (1 << 0)
63 /* Set if user does not want table to auto-resize when sufficiently empty. */
64 #define HASH_FLAG_NO_AUTO_SHRINK (1 << 1)
65 /* Set when hash_next is in the process of iterating through this hash table. */
66 #define HASH_FLAG_HASH_NEXT_IN_PROGRESS (1 << 2)
70 /* Function to compute the "sum" of a hash key.
71 Hash function is this sum modulo the prime size of
72 the hash table (vec_len (v)). */
73 hash_key_sum_function_t *key_sum;
75 /* Special values for key_sum "function". */
76 #define KEY_FUNC_NONE (0) /*< sum = key */
77 #define KEY_FUNC_POINTER_UWORD (1) /*< sum = *(uword *) key */
78 #define KEY_FUNC_POINTER_U32 (2) /*< sum = *(u32 *) key */
79 #define KEY_FUNC_STRING (3) /*< sum = string_key_sum, etc. */
81 /* key comparison function */
82 hash_key_equal_function_t *key_equal;
84 /* Hook for user's data. Used to parameterize sum/equal functions. */
87 /* Format a (k,v) pair */
88 format_function_t *format_pair;
90 /* Format function arg */
91 void *format_pair_arg;
93 /* Bit i is set if pair i is a user object (as opposed to being
94 either zero or an indirect array of pairs). */
98 /* Hash header size in bytes */
100 hash_header_bytes (void *v)
103 uword is_user_bytes =
104 (sizeof (h->is_user[0]) * vec_len (v)) / BITS (h->is_user[0]);
105 return sizeof (h[0]) + is_user_bytes;
108 /* Returns a pointer to the hash header given the vector pointer */
109 always_inline hash_t *
110 hash_header (void *v)
112 return vec_header (v, hash_header_bytes (v));
115 /* Number of elements in the hash table */
119 hash_t *h = hash_header (v);
120 return v ? h->elts : 0;
123 /* Number of elements the hash table can hold */
125 hash_capacity (void *v)
130 /* Returns 1 if the hash pair contains user data */
132 hash_is_user (void *v, uword i)
134 hash_t *h = hash_header (v);
135 uword i0 = i / BITS (h->is_user[0]);
136 uword i1 = i % BITS (h->is_user[0]);
137 return (h->is_user[i0] & ((uword) 1 << i1)) != 0;
140 /* Set the format function and format argument for a hash table */
142 hash_set_pair_format (void *v,
143 format_function_t * format_pair, void *format_pair_arg)
145 hash_t *h = hash_header (v);
146 h->format_pair = format_pair;
147 h->format_pair_arg = format_pair_arg;
150 /* Set hash table flags */
152 hash_set_flags (void *v, uword flags)
154 hash_header (v)->flags |= flags;
157 /* Key value pairs. */
163 /* The Value. Length is 2^log2_pair_size - 1. */
167 /* The indirect pair structure
169 If log2_pair_size > 0 we overload hash pairs
170 with indirect pairs for buckets with more than one
177 u8 pad[sizeof (uword) - sizeof (hash_pair_t *)];
178 /* allocated length */
181 hash_pair_indirect_t;
183 /* Direct / Indirect pair union */
187 hash_pair_indirect_t indirect;
190 #define LOG2_ALLOC_BITS (5)
191 #define PAIR_BITS (BITS (uword) - LOG2_ALLOC_BITS)
193 /* Log2 number of bytes allocated in pairs array. */
195 indirect_pair_get_log2_bytes (hash_pair_indirect_t * p)
197 return p->alloc_len >> PAIR_BITS;
200 /* Get the length of an indirect pair */
202 indirect_pair_get_len (hash_pair_indirect_t * p)
207 return p->alloc_len & (((uword) 1 << PAIR_BITS) - 1);
210 /* Set the length of an indirect pair */
212 indirect_pair_set (hash_pair_indirect_t * p, uword log2_alloc, uword len)
214 ASSERT (len < ((uword) 1 << PAIR_BITS));
215 ASSERT (log2_alloc < ((uword) 1 << LOG2_ALLOC_BITS));
216 p->alloc_len = (log2_alloc << PAIR_BITS) | len;
219 /* internal routine to fetch value for given key */
220 uword *_hash_get (void *v, uword key);
222 /* internal routine to fetch value (key, value) pair for given key */
223 hash_pair_t *_hash_get_pair (void *v, uword key);
225 /* internal routine to unset a (key, value) pair */
226 void *_hash_unset (void *v, uword key, void *old_value);
228 /* internal routine to set a (key, value) pair, return the old value */
229 void *_hash_set3 (void *v, uword key, void *value, void *old_value);
231 /* Resize a hash table */
232 void *hash_resize (void *old, uword new_size);
234 /* duplicate a hash table */
235 void *hash_dup (void *old);
237 /* Returns the number of bytes used by a hash table */
238 uword hash_bytes (void *v);
240 /* Public macro to set a (key, value) pair, return the old value */
241 #define hash_set3(h,key,value,old_value) \
243 uword _v = (uword) (value); \
244 (h) = _hash_set3 ((h), (uword) (key), (void *) &_v, (old_value)); \
247 /* Public macro to fetch value for given key */
248 #define hash_get(h,key) _hash_get ((h), (uword) (key))
250 /* Public macro to fetch value (key, value) pair for given key */
251 #define hash_get_pair(h,key) _hash_get_pair ((h), (uword) (key))
253 /* Public macro to set a (key, value) pair */
254 #define hash_set(h,key,value) hash_set3(h,key,value,0)
256 /* Public macro to set (key, 0) pair */
257 #define hash_set1(h,key) (h) = _hash_set3(h,(uword) (key),0,0)
259 /* Public macro to unset a (key, value) pair */
260 #define hash_unset(h,key) ((h) = _hash_unset ((h), (uword) (key),0))
262 /* Public macro to unset a (key, value) pair, return the old value */
263 #define hash_unset3(h,key,old_value) ((h) = _hash_unset ((h), (uword) (key), (void *) (old_value)))
265 /* get/set/unset for pointer keys. */
267 /* Public macro to fetch value for given pointer key */
268 #define hash_get_mem(h,key) _hash_get ((h), pointer_to_uword (key))
270 /* Public macro to fetch (key, value) for given pointer key */
271 #define hash_get_pair_mem(h,key) _hash_get_pair ((h), pointer_to_uword (key))
273 /* Public macro to set (key, value) for pointer key */
274 #define hash_set_mem(h,key,value) hash_set3 (h, pointer_to_uword (key), (value), 0)
276 /* Public macro to set (key, 0) for pointer key */
277 #define hash_set1_mem(h,key) hash_set3 ((h), pointer_to_uword (key), 0, 0)
279 /* Public macro to unset (key, value) for pointer key */
280 #define hash_unset_mem(h,key) ((h) = _hash_unset ((h), pointer_to_uword (key),0))
282 /* internal routine to free a hash table */
283 extern void *_hash_free (void *v);
285 /* Public macro to free a hash table */
286 #define hash_free(h) (h) = _hash_free ((h))
288 clib_error_t *hash_validate (void *v);
290 /* Public inline funcion to get the number of value bytes for a hash table */
292 hash_value_bytes (hash_t * h)
295 return (sizeof (p->value[0]) << h->log2_pair_size) - sizeof (p->key);
298 /* Public inline funcion to get log2(size of a (key,value) pair) */
300 hash_pair_log2_bytes (hash_t * h)
302 uword log2_bytes = h->log2_pair_size;
303 ASSERT (BITS (hash_pair_t) == 32 || BITS (hash_pair_t) == 64);
304 if (BITS (hash_pair_t) == 32)
306 else if (BITS (hash_pair_t) == 64)
311 /* Public inline funcion to get size of a (key,value) pair */
313 hash_pair_bytes (hash_t * h)
315 return (uword) 1 << hash_pair_log2_bytes (h);
318 /* Public inline funcion to advance a pointer past one (key,value) pair */
320 hash_forward1 (hash_t * h, void *v)
322 return (u8 *) v + hash_pair_bytes (h);
325 /* Public inline funcion to advance a pointer past N (key,value) pairs */
327 hash_forward (hash_t * h, void *v, uword n)
329 return (u8 *) v + ((n * sizeof (hash_pair_t)) << h->log2_pair_size);
332 /** Iterate over hash pairs.
334 @param p The current (key,value) pair. This should be of type
335 <code>(hash_pair_t *)</code>.
336 @param v The hash table to iterate.
337 @param body The operation to perform on each (key,value) pair.
339 Executes the expression or code block @c body with each active hash pair.
341 /* A previous version of this macro made use of the hash_pair_union_t
342 * structure; this version does not since that approach mightily upset
343 * the static analysis tool. In the rare chance someone is reading this
344 * code, pretend that _p below is of type hash_pair_union_t and that when
345 * used as an rvalue it's really using one of the union members as the
346 * rvalue. If you were confused before you might be marginally less
349 #define hash_foreach_pair(p,v,body) \
351 __label__ _hash_foreach_done; \
352 hash_t * _h = hash_header (v); \
354 hash_pair_t * _q, * _q_end; \
355 uword _i, _i1, _id, _pair_increment; \
359 _pair_increment = 1; \
361 _pair_increment = 1 << _h->log2_pair_size; \
362 while (_i < hash_capacity (v)) \
364 _id = _h->is_user[_i / BITS (_h->is_user[0])]; \
365 _i1 = _i + BITS (_h->is_user[0]); \
371 _q_end = _q + _pair_increment; \
375 hash_pair_indirect_t * _pi = _p; \
377 if (_h->log2_pair_size > 0) \
378 _q_end = hash_forward (_h, _q, indirect_pair_get_len (_pi)); \
380 _q_end = vec_end (_q); \
383 /* Loop through all elements in bucket. \
384 Bucket may have 0 1 or more (indirect case) pairs. */ \
385 while (_q < _q_end) \
387 uword _break_in_body = 1; \
391 _break_in_body = 0; \
393 if (_break_in_body) \
394 goto _hash_foreach_done; \
395 _q += _pair_increment; \
398 _p = (hash_pair_t *)_p + _pair_increment; \
401 } while (_i < _i1); \
403 _hash_foreach_done: \
404 /* Be silent Mr. Compiler-Warning. */ \
408 /* Iterate over key/value pairs
410 @param key_var the current key
411 @param value_var the current value
412 @param h the hash table to iterate across
413 @param body the operation to perform on each (key_var,value_var) pair.
415 calls body with each active hash pair
417 /* Iteratate over key/value pairs. */
418 #define hash_foreach(key_var,value_var,h,body) \
421 hash_foreach_pair (_r, (h), { \
422 (key_var) = (__typeof__ (key_var)) _r->key; \
423 (value_var) = (__typeof__ (value_var)) _r->value[0]; \
424 do { body; } while (0); \
428 /* Iterate over key/value pairs for pointer key hash tables
430 @param key_var the current key
431 @param value_var the current value
432 @param h the hash table to iterate across
433 @param body the operation to perform on each (key_var,value_var) pair.
435 calls body with each active hash pair
437 #define hash_foreach_mem(key_var,value_var,h,body) \
440 hash_foreach_pair (_r, (h), { \
441 (key_var) = (__typeof__ (key_var)) uword_to_pointer (_r->key, void *); \
442 (value_var) = (__typeof__ (value_var)) _r->value[0]; \
443 do { body; } while (0); \
447 /* Support for iteration through hash table. */
449 /* This struct saves iteration state for hash_next.
450 None of these fields are meant to be visible to the user.
451 Hence, the cryptic short-hand names. */
457 hash_pair_t *hash_next (void *v, hash_next_t * hn);
459 void *_hash_create (uword elts, hash_t * h);
462 hash_set_value_bytes (hash_t * h, uword value_bytes)
466 max_log2 ((sizeof (p->key) + value_bytes + sizeof (p->key) -
467 1) / sizeof (p->key));
470 #define hash_create2(_elts,_user,_value_bytes, \
471 _key_sum,_key_equal, \
472 _format_pair,_format_pair_arg) \
475 memset (&_h, 0, sizeof (_h)); \
477 _h.key_sum = (hash_key_sum_function_t *) (_key_sum); \
478 _h.key_equal = (_key_equal); \
479 hash_set_value_bytes (&_h, (_value_bytes)); \
480 _h.format_pair = (format_function_t *) (_format_pair); \
481 _h.format_pair_arg = (_format_pair_arg); \
482 _hash_create ((_elts), &_h); \
485 /* Hash function based on that of Bob Jenkins (bob_jenkins@compuserve.com).
486 Public domain per: http://www.burtleburtle.net/bob/hash/doobs.html
489 #define hash_mix_step(a,b,c,s0,s1,s2) \
491 (a) -= (b) + (c); (a) ^= (c) >> (s0); \
492 (b) -= (c) + (a); (b) ^= (a) << (s1); \
493 (c) -= (a) + (b); (c) ^= (b) >> (s2); \
496 #define hash_mix32_step_1(a,b,c) hash_mix_step(a,b,c,13,8,13)
497 #define hash_mix32_step_2(a,b,c) hash_mix_step(a,b,c,12,16,5)
498 #define hash_mix32_step_3(a,b,c) hash_mix_step(a,b,c,3,10,15)
500 #define hash_mix64_step_1(a,b,c) hash_mix_step(a,b,c,43,9,8)
501 #define hash_mix64_step_2(a,b,c) hash_mix_step(a,b,c,38,23,5)
502 #define hash_mix64_step_3(a,b,c) hash_mix_step(a,b,c,35,49,11)
503 #define hash_mix64_step_4(a,b,c) hash_mix_step(a,b,c,12,18,22)
505 /* Hash function based on that of Bob Jenkins (bob_jenkins@compuserve.com).
507 #define hash_mix64(a0,b0,c0) \
509 hash_mix64_step_1 (a0, b0, c0); \
510 hash_mix64_step_2 (a0, b0, c0); \
511 hash_mix64_step_3 (a0, b0, c0); \
512 hash_mix64_step_4 (a0, b0, c0); \
515 #define hash_mix32(a0,b0,c0) \
517 hash_mix32_step_1 (a0, b0, c0); \
518 hash_mix32_step_2 (a0, b0, c0); \
519 hash_mix32_step_3 (a0, b0, c0); \
522 /* Finalize from Bob Jenkins lookup3.c */
525 hash32_rotate_left (u32 x, u32 i)
527 return (x << i) | (x >> (BITS (i) - i));
530 #define hash_v3_mix32(a,b,c) \
532 (a) -= (c); (a) ^= hash32_rotate_left ((c), 4); (c) += (b); \
533 (b) -= (a); (b) ^= hash32_rotate_left ((a), 6); (a) += (c); \
534 (c) -= (b); (c) ^= hash32_rotate_left ((b), 8); (b) += (a); \
535 (a) -= (c); (a) ^= hash32_rotate_left ((c),16); (c) += (b); \
536 (b) -= (a); (b) ^= hash32_rotate_left ((a),19); (a) += (c); \
537 (c) -= (b); (c) ^= hash32_rotate_left ((b), 4); (b) += (a); \
540 #define hash_v3_finalize32(a,b,c) \
542 (c) ^= (b); (c) -= hash32_rotate_left ((b), 14); \
543 (a) ^= (c); (a) -= hash32_rotate_left ((c), 11); \
544 (b) ^= (a); (b) -= hash32_rotate_left ((a), 25); \
545 (c) ^= (b); (c) -= hash32_rotate_left ((b), 16); \
546 (a) ^= (c); (a) -= hash32_rotate_left ((c), 4); \
547 (b) ^= (a); (b) -= hash32_rotate_left ((a), 14); \
548 (c) ^= (b); (c) -= hash32_rotate_left ((b), 24); \
551 /* 32 bit mixing/finalize in steps. */
553 #define hash_v3_mix32_step1(a,b,c) \
555 (a) -= (c); (a) ^= hash32_rotate_left ((c), 4); (c) += (b); \
556 (b) -= (a); (b) ^= hash32_rotate_left ((a), 6); (a) += (c); \
559 #define hash_v3_mix32_step2(a,b,c) \
561 (c) -= (b); (c) ^= hash32_rotate_left ((b), 8); (b) += (a); \
562 (a) -= (c); (a) ^= hash32_rotate_left ((c),16); (c) += (b); \
565 #define hash_v3_mix32_step3(a,b,c) \
567 (b) -= (a); (b) ^= hash32_rotate_left ((a),19); (a) += (c); \
568 (c) -= (b); (c) ^= hash32_rotate_left ((b), 4); (b) += (a); \
571 #define hash_v3_finalize32_step1(a,b,c) \
573 (c) ^= (b); (c) -= hash32_rotate_left ((b), 14); \
574 (a) ^= (c); (a) -= hash32_rotate_left ((c), 11); \
577 #define hash_v3_finalize32_step2(a,b,c) \
579 (b) ^= (a); (b) -= hash32_rotate_left ((a), 25); \
580 (c) ^= (b); (c) -= hash32_rotate_left ((b), 16); \
583 #define hash_v3_finalize32_step3(a,b,c) \
585 (a) ^= (c); (a) -= hash32_rotate_left ((c), 4); \
586 (b) ^= (a); (b) -= hash32_rotate_left ((a), 14); \
587 (c) ^= (b); (c) -= hash32_rotate_left ((b), 24); \
590 /* Vector v3 mixing/finalize. */
591 #define hash_v3_mix_step_1_u32x(a,b,c) \
593 (a) -= (c); (a) ^= u32x_irotate_left ((c), 4); (c) += (b); \
594 (b) -= (a); (b) ^= u32x_irotate_left ((a), 6); (a) += (c); \
595 (c) -= (b); (c) ^= u32x_irotate_left ((b), 8); (b) += (a); \
598 #define hash_v3_mix_step_2_u32x(a,b,c) \
600 (a) -= (c); (a) ^= u32x_irotate_left ((c),16); (c) += (b); \
601 (b) -= (a); (b) ^= u32x_irotate_left ((a),19); (a) += (c); \
602 (c) -= (b); (c) ^= u32x_irotate_left ((b), 4); (b) += (a); \
605 #define hash_v3_finalize_step_1_u32x(a,b,c) \
607 (c) ^= (b); (c) -= u32x_irotate_left ((b), 14); \
608 (a) ^= (c); (a) -= u32x_irotate_left ((c), 11); \
609 (b) ^= (a); (b) -= u32x_irotate_left ((a), 25); \
612 #define hash_v3_finalize_step_2_u32x(a,b,c) \
614 (c) ^= (b); (c) -= u32x_irotate_left ((b), 16); \
615 (a) ^= (c); (a) -= u32x_irotate_left ((c), 4); \
616 (b) ^= (a); (b) -= u32x_irotate_left ((a), 14); \
617 (c) ^= (b); (c) -= u32x_irotate_left ((b), 24); \
620 #define hash_v3_mix_u32x(a,b,c) \
622 hash_v3_mix_step_1_u32x(a,b,c); \
623 hash_v3_mix_step_2_u32x(a,b,c); \
626 #define hash_v3_finalize_u32x(a,b,c) \
628 hash_v3_finalize_step_1_u32x(a,b,c); \
629 hash_v3_finalize_step_2_u32x(a,b,c); \
632 extern uword hash_memory (void *p, word n_bytes, uword state);
634 extern uword mem_key_sum (hash_t * h, uword key);
635 extern uword mem_key_equal (hash_t * h, uword key1, uword key2);
637 #define hash_create_mem(elts,key_bytes,value_bytes) \
638 hash_create2((elts),(key_bytes),(value_bytes),mem_key_sum,mem_key_equal,0,0)
640 extern uword vec_key_sum (hash_t * h, uword key);
641 extern uword vec_key_equal (hash_t * h, uword key1, uword key2);
642 extern u8 *vec_key_format_pair (u8 * s, va_list * args);
644 #define hash_create_vec(elts,key_bytes,value_bytes) \
645 hash_create2((elts),(key_bytes),(value_bytes),\
646 vec_key_sum,vec_key_equal,vec_key_format_pair,0)
648 extern uword string_key_sum (hash_t * h, uword key);
649 extern uword string_key_equal (hash_t * h, uword key1, uword key2);
650 extern u8 *string_key_format_pair (u8 * s, va_list * args);
652 #define hash_create_string(elts,value_bytes) \
653 hash_create2((elts),0,(value_bytes), \
654 (hash_key_sum_function_t *) KEY_FUNC_STRING, \
655 (hash_key_equal_function_t *)KEY_FUNC_STRING, \
658 #define hash_create(elts,value_bytes) \
659 hash_create2((elts),0,(value_bytes), \
660 (hash_key_sum_function_t *) KEY_FUNC_NONE, \
661 (hash_key_equal_function_t *) KEY_FUNC_NONE, \
664 #define hash_create_uword(elts,value_bytes) \
665 hash_create2((elts),0,(value_bytes), \
666 (hash_key_sum_function_t *) KEY_FUNC_POINTER_UWORD, \
667 (hash_key_equal_function_t *) KEY_FUNC_POINTER_UWORD, \
670 #define hash_create_u32(elts,value_bytes) \
671 hash_create2((elts),0,(value_bytes), \
672 (hash_key_sum_function_t *) KEY_FUNC_POINTER_U32, \
673 (hash_key_equal_function_t *) KEY_FUNC_POINTER_U32, \
676 u8 *format_hash (u8 * s, va_list * va);
678 /* Looks up input in hash table indexed by either vec string or
679 c string (null terminated). */
680 unformat_function_t unformat_hash_vec_string;
681 unformat_function_t unformat_hash_string;
683 /* Main test routine. */
684 int test_hash_main (unformat_input_t * input);
686 #endif /* included_hash_h */
689 * fd.io coding-style-patch-verification: ON
692 * eval: (c-set-style "gnu")