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[perl5.git] / hv_func.h
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1/* hash a key
2 *--------------------------------------------------------------------------------------
3 * The "hash seed" feature was added in Perl 5.8.1 to perturb the results
4 * to avoid "algorithmic complexity attacks".
5 *
6 * If USE_HASH_SEED is defined, hash randomisation is done by default
7 * If USE_HASH_SEED_EXPLICIT is defined, hash randomisation is done
8 * only if the environment variable PERL_HASH_SEED is set.
9 * (see also perl.c:perl_parse() and S_init_tls_and_interp() and util.c:get_hash_seed())
10 */
11
12#ifndef PERL_SEEN_HV_FUNC_H /* compile once */
13#define PERL_SEEN_HV_FUNC_H
14
15#if !( 0 \
e6b54db6 16 || defined(PERL_HASH_FUNC_SIPHASH) \
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17 || defined(PERL_HASH_FUNC_SDBM) \
18 || defined(PERL_HASH_FUNC_DJB2) \
19 || defined(PERL_HASH_FUNC_SUPERFAST) \
20 || defined(PERL_HASH_FUNC_MURMUR3) \
21 || defined(PERL_HASH_FUNC_ONE_AT_A_TIME) \
b1300a73 22 || defined(PERL_HASH_FUNC_ONE_AT_A_TIME_HARD) \
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23 || defined(PERL_HASH_FUNC_ONE_AT_A_TIME_OLD) \
24 )
b1300a73 25#define PERL_HASH_FUNC_ONE_AT_A_TIME_HARD
4d3a042d 26#endif
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27
28#if defined(PERL_HASH_FUNC_SIPHASH)
29# define PERL_HASH_FUNC "SIPHASH_2_4"
30# define PERL_HASH_SEED_BYTES 16
3d53a8ea 31# define PERL_HASH_WITH_SEED(seed,hash,str,len) (hash)= S_perl_hash_siphash_2_4((seed),(U8*)(str),(len))
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32#elif defined(PERL_HASH_FUNC_SUPERFAST)
33# define PERL_HASH_FUNC "SUPERFAST"
34# define PERL_HASH_SEED_BYTES 4
3d53a8ea 35# define PERL_HASH_WITH_SEED(seed,hash,str,len) (hash)= S_perl_hash_superfast((seed),(U8*)(str),(len))
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36#elif defined(PERL_HASH_FUNC_MURMUR3)
37# define PERL_HASH_FUNC "MURMUR3"
38# define PERL_HASH_SEED_BYTES 4
3d53a8ea 39# define PERL_HASH_WITH_SEED(seed,hash,str,len) (hash)= S_perl_hash_murmur3((seed),(U8*)(str),(len))
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40#elif defined(PERL_HASH_FUNC_DJB2)
41# define PERL_HASH_FUNC "DJB2"
42# define PERL_HASH_SEED_BYTES 4
3d53a8ea 43# define PERL_HASH_WITH_SEED(seed,hash,str,len) (hash)= S_perl_hash_djb2((seed),(U8*)(str),(len))
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44#elif defined(PERL_HASH_FUNC_SDBM)
45# define PERL_HASH_FUNC "SDBM"
46# define PERL_HASH_SEED_BYTES 4
3d53a8ea 47# define PERL_HASH_WITH_SEED(seed,hash,str,len) (hash)= S_perl_hash_sdbm((seed),(U8*)(str),(len))
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48#elif defined(PERL_HASH_FUNC_ONE_AT_A_TIME_HARD)
49# define PERL_HASH_FUNC "ONE_AT_A_TIME_HARD"
50# define PERL_HASH_SEED_BYTES 8
3d53a8ea 51# define PERL_HASH_WITH_SEED(seed,hash,str,len) (hash)= S_perl_hash_one_at_a_time_hard((seed),(U8*)(str),(len))
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52#elif defined(PERL_HASH_FUNC_ONE_AT_A_TIME)
53# define PERL_HASH_FUNC "ONE_AT_A_TIME"
54# define PERL_HASH_SEED_BYTES 4
3d53a8ea 55# define PERL_HASH_WITH_SEED(seed,hash,str,len) (hash)= S_perl_hash_one_at_a_time((seed),(U8*)(str),(len))
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56#elif defined(PERL_HASH_FUNC_ONE_AT_A_TIME_OLD)
57# define PERL_HASH_FUNC "ONE_AT_A_TIME_OLD"
58# define PERL_HASH_SEED_BYTES 4
3d53a8ea 59# define PERL_HASH_WITH_SEED(seed,hash,str,len) (hash)= S_perl_hash_old_one_at_a_time((seed),(U8*)(str),(len))
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60#endif
61
3d53a8ea 62#ifndef PERL_HASH_WITH_SEED
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63#error "No hash function defined!"
64#endif
65#ifndef PERL_HASH_SEED_BYTES
66#error "PERL_HASH_SEED_BYTES not defined"
67#endif
68#ifndef PERL_HASH_FUNC
69#error "PERL_HASH_FUNC not defined"
70#endif
71
72#ifndef PERL_HASH_SEED
73# if defined(USE_HASH_SEED) || defined(USE_HASH_SEED_EXPLICIT)
74# define PERL_HASH_SEED PL_hash_seed
75# elif PERL_HASH_SEED_BYTES == 4
76# define PERL_HASH_SEED "PeRl"
77# elif PERL_HASH_SEED_BYTES == 16
78# define PERL_HASH_SEED "PeRlHaShhAcKpErl"
79# else
80# error "No PERL_HASH_SEED definition for " PERL_HASH_FUNC
81# endif
82#endif
83
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84#define PERL_HASH(hash,str,len) PERL_HASH_WITH_SEED(PERL_HASH_SEED,hash,str,len)
85
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86/*-----------------------------------------------------------------------------
87 * Endianess, misalignment capabilities and util macros
88 *
89 * The following 3 macros are defined in this section. The other macros defined
90 * are only needed to help derive these 3.
91 *
92 * U8TO32_LE(x) Read a little endian unsigned 32-bit int
93 * UNALIGNED_SAFE Defined if READ_UINT32 works on non-word boundaries
94 * ROTL32(x,r) Rotate x left by r bits
95 */
96
97#if (defined(__GNUC__) && defined(__i386__)) || defined(__WATCOMC__) \
0a35fd8a 98 || defined(_MSC_VER) || defined (__TURBOC__)
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99#define U8TO16_LE(d) (*((const U16 *) (d)))
100#endif
101
102#if !defined (U8TO16_LE)
103#define U8TO16_LE(d) ((((const U8 *)(d))[1] << 8)\
104 +((const U8 *)(d))[0])
105#endif
106
107
108/* Now find best way we can to READ_UINT32 */
109#if (BYTEORDER == 0x1234 || BYTEORDER == 0x12345678) && U32SIZE == 4
110 /* CPU endian matches murmurhash algorithm, so read 32-bit word directly */
111 #define U8TO32_LE(ptr) (*((U32*)(ptr)))
112#elif BYTEORDER == 0x4321 || BYTEORDER == 0x87654321
113 /* TODO: Add additional cases below where a compiler provided bswap32 is available */
114 #if defined(__GNUC__) && (__GNUC__>4 || (__GNUC__==4 && __GNUC_MINOR__>=3))
115 #define U8TO32_LE(ptr) (__builtin_bswap32(*((U32*)(ptr))))
116 #else
117 /* Without a known fast bswap32 we're just as well off doing this */
118 #define U8TO32_LE(ptr) (ptr[0]|ptr[1]<<8|ptr[2]<<16|ptr[3]<<24)
119 #define UNALIGNED_SAFE
120 #endif
121#else
122 /* Unknown endianess so last resort is to read individual bytes */
123 #define U8TO32_LE(ptr) (ptr[0]|ptr[1]<<8|ptr[2]<<16|ptr[3]<<24)
124 /* Since we're not doing word-reads we can skip the messing about with realignment */
125 #define UNALIGNED_SAFE
126#endif
127
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128#ifdef HAS_QUAD
129#ifndef U64TYPE
130/* This probably isn't going to work, but failing with a compiler error due to
131 lack of uint64_t is no worse than failing right now with an #error. */
132#define U64TYPE uint64_t
133#endif
134#endif
135
136/* Find best way to ROTL32/ROTL64 */
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137#if defined(_MSC_VER)
138 #include <stdlib.h> /* Microsoft put _rotl declaration in here */
139 #define ROTL32(x,r) _rotl(x,r)
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140 #ifdef HAS_QUAD
141 #define ROTL64(x,r) _rotl64(x,r)
142 #endif
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143#else
144 /* gcc recognises this code and generates a rotate instruction for CPUs with one */
145 #define ROTL32(x,r) (((U32)x << r) | ((U32)x >> (32 - r)))
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146 #ifdef HAS_QUAD
147 #define ROTL64(x,r) (((U64TYPE)x << r) | ((U64TYPE)x >> (64 - r)))
148 #endif
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149#endif
150
151
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152#ifdef UV_IS_QUAD
153#define ROTL_UV(x,r) ROTL64(x,r)
154#else
155#define ROTL_UV(x,r) ROTL32(x,r)
156#endif
157
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158/* This is SipHash by Jean-Philippe Aumasson and Daniel J. Bernstein.
159 * The authors claim it is relatively secure compared to the alternatives
160 * and that performance wise it is a suitable hash for languages like Perl.
161 * See:
162 *
163 * https://www.131002.net/siphash/
164 *
165 * This implementation seems to perform slightly slower than one-at-a-time for
166 * short keys, but degrades slower for longer keys. Murmur Hash outperforms it
167 * regardless of keys size.
168 *
169 * It is 64 bit only.
170 */
171
172#ifdef HAS_QUAD
173
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174#define U8TO64_LE(p) \
175 (((U64TYPE)((p)[0]) ) | \
176 ((U64TYPE)((p)[1]) << 8) | \
177 ((U64TYPE)((p)[2]) << 16) | \
178 ((U64TYPE)((p)[3]) << 24) | \
179 ((U64TYPE)((p)[4]) << 32) | \
180 ((U64TYPE)((p)[5]) << 40) | \
181 ((U64TYPE)((p)[6]) << 48) | \
182 ((U64TYPE)((p)[7]) << 56))
183
184#define SIPROUND \
185 do { \
186 v0 += v1; v1=ROTL64(v1,13); v1 ^= v0; v0=ROTL64(v0,32); \
187 v2 += v3; v3=ROTL64(v3,16); v3 ^= v2; \
188 v0 += v3; v3=ROTL64(v3,21); v3 ^= v0; \
189 v2 += v1; v1=ROTL64(v1,17); v1 ^= v2; v2=ROTL64(v2,32); \
190 } while(0)
191
192/* SipHash-2-4 */
193
194PERL_STATIC_INLINE U32
195S_perl_hash_siphash_2_4(const unsigned char * const seed, const unsigned char *in, const STRLEN inlen) {
196 /* "somepseudorandomlygeneratedbytes" */
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197 U64TYPE v0 = UINT64_C(0x736f6d6570736575);
198 U64TYPE v1 = UINT64_C(0x646f72616e646f6d);
199 U64TYPE v2 = UINT64_C(0x6c7967656e657261);
200 U64TYPE v3 = UINT64_C(0x7465646279746573);
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201
202 U64TYPE b;
203 U64TYPE k0 = ((U64TYPE*)seed)[0];
204 U64TYPE k1 = ((U64TYPE*)seed)[1];
205 U64TYPE m;
206 const int left = inlen & 7;
207 const U8 *end = in + inlen - left;
208
209 b = ( ( U64TYPE )(inlen) ) << 56;
210 v3 ^= k1;
211 v2 ^= k0;
212 v1 ^= k1;
213 v0 ^= k0;
214
215 for ( ; in != end; in += 8 )
216 {
217 m = U8TO64_LE( in );
218 v3 ^= m;
219 SIPROUND;
220 SIPROUND;
221 v0 ^= m;
222 }
223
224 switch( left )
225 {
226 case 7: b |= ( ( U64TYPE )in[ 6] ) << 48;
227 case 6: b |= ( ( U64TYPE )in[ 5] ) << 40;
228 case 5: b |= ( ( U64TYPE )in[ 4] ) << 32;
229 case 4: b |= ( ( U64TYPE )in[ 3] ) << 24;
230 case 3: b |= ( ( U64TYPE )in[ 2] ) << 16;
231 case 2: b |= ( ( U64TYPE )in[ 1] ) << 8;
232 case 1: b |= ( ( U64TYPE )in[ 0] ); break;
233 case 0: break;
234 }
235
236 v3 ^= b;
237 SIPROUND;
238 SIPROUND;
239 v0 ^= b;
240
241 v2 ^= 0xff;
242 SIPROUND;
243 SIPROUND;
244 SIPROUND;
245 SIPROUND;
246 b = v0 ^ v1 ^ v2 ^ v3;
247 return (U32)(b & U32_MAX);
248}
249#endif /* defined(HAS_QUAD) */
250
251/* FYI: This is the "Super-Fast" algorithm mentioned by Bob Jenkins in
252 * (http://burtleburtle.net/bob/hash/doobs.html)
253 * It is by Paul Hsieh (c) 2004 and is analysed here
254 * http://www.azillionmonkeys.com/qed/hash.html
255 * license terms are here:
256 * http://www.azillionmonkeys.com/qed/weblicense.html
257 */
258
259
260PERL_STATIC_INLINE U32
261S_perl_hash_superfast(const unsigned char * const seed, const unsigned char *str, STRLEN len) {
262 U32 hash = *((U32*)seed) + len;
263 U32 tmp;
264 int rem= len & 3;
265 len >>= 2;
266
267 for (;len > 0; len--) {
268 hash += U8TO16_LE (str);
269 tmp = (U8TO16_LE (str+2) << 11) ^ hash;
270 hash = (hash << 16) ^ tmp;
271 str += 2 * sizeof (U16);
272 hash += hash >> 11;
273 }
274
275 /* Handle end cases */
276 switch (rem) { \
277 case 3: hash += U8TO16_LE (str);
278 hash ^= hash << 16;
279 hash ^= str[sizeof (U16)] << 18;
280 hash += hash >> 11;
281 break;
282 case 2: hash += U8TO16_LE (str);
283 hash ^= hash << 11;
284 hash += hash >> 17;
285 break;
286 case 1: hash += *str;
287 hash ^= hash << 10;
288 hash += hash >> 1;
289 }
290 /* Force "avalanching" of final 127 bits */
291 hash ^= hash << 3;
292 hash += hash >> 5;
293 hash ^= hash << 4;
294 hash += hash >> 17;
295 hash ^= hash << 25;
296 return (hash + (hash >> 6));
297}
298
299
300/*-----------------------------------------------------------------------------
301 * MurmurHash3 was written by Austin Appleby, and is placed in the public
302 * domain.
303 *
304 * This implementation was originally written by Shane Day, and is also public domain,
305 * and was modified to function as a macro similar to other perl hash functions by
306 * Yves Orton.
307 *
308 * This is a portable ANSI C implementation of MurmurHash3_x86_32 (Murmur3A)
309 * with support for progressive processing.
310 *
311 * If you want to understand the MurmurHash algorithm you would be much better
312 * off reading the original source. Just point your browser at:
313 * http://code.google.com/p/smhasher/source/browse/trunk/MurmurHash3.cpp
314 *
315 * How does it work?
316 *
317 * We can only process entire 32 bit chunks of input, except for the very end
318 * that may be shorter.
319 *
320 * To handle endianess I simply use a macro that reads a U32 and define
321 * that macro to be a direct read on little endian machines, a read and swap
322 * on big endian machines, or a byte-by-byte read if the endianess is unknown.
323 */
324
325
326/*-----------------------------------------------------------------------------
327 * Core murmurhash algorithm macros */
328
329#define MURMUR_C1 (0xcc9e2d51)
330#define MURMUR_C2 (0x1b873593)
331#define MURMUR_C3 (0xe6546b64)
332#define MURMUR_C4 (0x85ebca6b)
333#define MURMUR_C5 (0xc2b2ae35)
334
335/* This is the main processing body of the algorithm. It operates
336 * on each full 32-bits of input. */
337#define MURMUR_DOBLOCK(h1, k1) STMT_START { \
338 k1 *= MURMUR_C1; \
339 k1 = ROTL32(k1,15); \
340 k1 *= MURMUR_C2; \
341 \
342 h1 ^= k1; \
343 h1 = ROTL32(h1,13); \
344 h1 = h1 * 5 + MURMUR_C3; \
345} STMT_END
346
347
348/* Append unaligned bytes to carry, forcing hash churn if we have 4 bytes */
349/* cnt=bytes to process, h1=name of h1 var, c=carry, n=bytes in c, ptr/len=payload */
350#define MURMUR_DOBYTES(cnt, h1, c, n, ptr, len) STMT_START { \
351 int MURMUR_DOBYTES_i = cnt; \
352 while(MURMUR_DOBYTES_i--) { \
353 c = c>>8 | *ptr++<<24; \
354 n++; len--; \
355 if(n==4) { \
356 MURMUR_DOBLOCK(h1, c); \
357 n = 0; \
358 } \
359 } \
360} STMT_END
361
362
363/* now we create the hash function */
364PERL_STATIC_INLINE U32
365S_perl_hash_murmur3(const unsigned char * const seed, const unsigned char *ptr, STRLEN len) {
366 U32 h1 = *((U32*)seed);
367 U32 k1;
368 U32 carry = 0;
369
370 const unsigned char *end;
371 int bytes_in_carry = 0; /* bytes in carry */
372 I32 total_length= len;
373
374#if defined(UNALIGNED_SAFE)
375 /* Handle carry: commented out as its only used in incremental mode - it never fires for us
376 int i = (4-n) & 3;
377 if(i && i <= len) {
378 MURMUR_DOBYTES(i, h1, carry, bytes_in_carry, ptr, len);
379 }
380 */
381
382 /* This CPU handles unaligned word access */
383 /* Process 32-bit chunks */
384 end = ptr + len/4*4;
385 for( ; ptr < end ; ptr+=4) {
386 k1 = U8TO32_LE(ptr);
387 MURMUR_DOBLOCK(h1, k1);
388 }
389#else
390 /* This CPU does not handle unaligned word access */
391
392 /* Consume enough so that the next data byte is word aligned */
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393 STRLEN i = -PTR2IV(ptr) & 3;
394 if(i && i <= len) {
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395 MURMUR_DOBYTES(i, h1, carry, bytes_in_carry, ptr, len);
396 }
397
398 /* We're now aligned. Process in aligned blocks. Specialise for each possible carry count */
399 end = ptr + len/4*4;
400 switch(bytes_in_carry) { /* how many bytes in carry */
401 case 0: /* c=[----] w=[3210] b=[3210]=w c'=[----] */
402 for( ; ptr < end ; ptr+=4) {
403 k1 = U8TO32_LE(ptr);
404 MURMUR_DOBLOCK(h1, k1);
405 }
406 break;
407 case 1: /* c=[0---] w=[4321] b=[3210]=c>>24|w<<8 c'=[4---] */
408 for( ; ptr < end ; ptr+=4) {
409 k1 = carry>>24;
410 carry = U8TO32_LE(ptr);
411 k1 |= carry<<8;
412 MURMUR_DOBLOCK(h1, k1);
413 }
414 break;
415 case 2: /* c=[10--] w=[5432] b=[3210]=c>>16|w<<16 c'=[54--] */
416 for( ; ptr < end ; ptr+=4) {
417 k1 = carry>>16;
418 carry = U8TO32_LE(ptr);
419 k1 |= carry<<16;
420 MURMUR_DOBLOCK(h1, k1);
421 }
422 break;
423 case 3: /* c=[210-] w=[6543] b=[3210]=c>>8|w<<24 c'=[654-] */
424 for( ; ptr < end ; ptr+=4) {
425 k1 = carry>>8;
426 carry = U8TO32_LE(ptr);
427 k1 |= carry<<24;
428 MURMUR_DOBLOCK(h1, k1);
429 }
430 }
431#endif
432 /* Advance over whole 32-bit chunks, possibly leaving 1..3 bytes */
433 len -= len/4*4;
434
435 /* Append any remaining bytes into carry */
436 MURMUR_DOBYTES(len, h1, carry, bytes_in_carry, ptr, len);
437
438 if (bytes_in_carry) {
439 k1 = carry >> ( 4 - bytes_in_carry ) * 8;
440 k1 *= MURMUR_C1;
441 k1 = ROTL32(k1,15);
442 k1 *= MURMUR_C2;
443 h1 ^= k1;
444 }
445 h1 ^= total_length;
446
447 /* fmix */
448 h1 ^= h1 >> 16;
449 h1 *= MURMUR_C4;
450 h1 ^= h1 >> 13;
451 h1 *= MURMUR_C5;
452 h1 ^= h1 >> 16;
453 return h1;
454}
455
456
457PERL_STATIC_INLINE U32
458S_perl_hash_djb2(const unsigned char * const seed, const unsigned char *str, const STRLEN len) {
459 const unsigned char * const end = (const unsigned char *)str + len;
54e07e2b 460 U32 hash = *((U32*)seed) + len;
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461 while (str < end) {
462 hash = ((hash << 5) + hash) + *str++;
463 }
464 return hash;
465}
466
467PERL_STATIC_INLINE U32
468S_perl_hash_sdbm(const unsigned char * const seed, const unsigned char *str, const STRLEN len) {
469 const unsigned char * const end = (const unsigned char *)str + len;
54e07e2b 470 U32 hash = *((U32*)seed) + len;
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471 while (str < end) {
472 hash = (hash << 6) + (hash << 16) - hash + *str++;
473 }
474 return hash;
475}
476
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477/* - ONE_AT_A_TIME_HARD is the 5.17+ recommend ONE_AT_A_TIME algorithm
478 * - ONE_AT_A_TIME_OLD is the unmodified 5.16 and older algorithm
479 * - ONE_AT_A_TIME is a 5.17+ tweak of ONE_AT_A_TIME_OLD to
480 * prevent strings of only \0 but different lengths from colliding
481 *
482 * Security-wise, from best to worst,
483 * ONE_AT_A_TIME_HARD > ONE_AT_A_TIME > ONE_AT_A_TIME_OLD
484 * There is a big drop-off in security between ONE_AT_A_TIME_HARD and
485 * ONE_AT_A_TIME
486 * */
4d3a042d 487
b1300a73 488/* This is the "One-at-a-Time" algorithm by Bob Jenkins
4d3a042d 489 * from requirements by Colin Plumb.
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490 * (http://burtleburtle.net/bob/hash/doobs.html)
491 * With seed/len tweak.
492 * */
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493PERL_STATIC_INLINE U32
494S_perl_hash_one_at_a_time(const unsigned char * const seed, const unsigned char *str, const STRLEN len) {
495 const unsigned char * const end = (const unsigned char *)str + len;
496 U32 hash = *((U32*)seed) + len;
497 while (str < end) {
498 hash += *str++;
499 hash += (hash << 10);
500 hash ^= (hash >> 6);
501 }
502 hash += (hash << 3);
503 hash ^= (hash >> 11);
504 return (hash + (hash << 15));
505}
506
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507/* Derived from "One-at-a-Time" algorithm by Bob Jenkins */
508PERL_STATIC_INLINE U32
509S_perl_hash_one_at_a_time_hard(const unsigned char * const seed, const unsigned char *str, const STRLEN len) {
510 const unsigned char * const end = (const unsigned char *)str + len;
511 U32 hash = *((U32*)seed) + len;
512
513 while (str < end) {
514 hash += (hash << 10);
515 hash ^= (hash >> 6);
516 hash += *str++;
517 }
518
519 hash += (hash << 10);
520 hash ^= (hash >> 6);
521 hash += seed[4];
522
523 hash += (hash << 10);
524 hash ^= (hash >> 6);
525 hash += seed[5];
526
527 hash += (hash << 10);
528 hash ^= (hash >> 6);
529 hash += seed[6];
530
531 hash += (hash << 10);
532 hash ^= (hash >> 6);
533 hash += seed[7];
534
535 hash += (hash << 10);
536 hash ^= (hash >> 6);
537
538 hash += (hash << 3);
539 hash ^= (hash >> 11);
540 return (hash + (hash << 15));
541}
542
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543PERL_STATIC_INLINE U32
544S_perl_hash_old_one_at_a_time(const unsigned char * const seed, const unsigned char *str, const STRLEN len) {
545 const unsigned char * const end = (const unsigned char *)str + len;
546 U32 hash = *((U32*)seed);
547 while (str < end) {
548 hash += *str++;
549 hash += (hash << 10);
550 hash ^= (hash >> 6);
551 }
552 hash += (hash << 3);
553 hash ^= (hash >> 11);
554 return (hash + (hash << 15));
555}
556
557/* legacy - only mod_perl should be doing this. */
558#ifdef PERL_HASH_INTERNAL_ACCESS
559#define PERL_HASH_INTERNAL(hash,str,len) PERL_HASH(hash,str,len)
560#endif
561
562#endif /*compile once*/
563
564/*
565 * Local variables:
566 * c-indentation-style: bsd
567 * c-basic-offset: 4
568 * indent-tabs-mode: nil
569 * End:
570 *
571 * ex: set ts=8 sts=4 sw=4 et:
572 */