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87d2c1ff LP |
1 | /* Slightly modified by Lennart Poettering, to avoid name clashes, and |
2 | * unexport a few functions. */ | |
3 | ||
4 | #include "lookup3.h" | |
5 | ||
6 | /* | |
7 | ------------------------------------------------------------------------------- | |
8 | lookup3.c, by Bob Jenkins, May 2006, Public Domain. | |
9 | ||
10 | These are functions for producing 32-bit hashes for hash table lookup. | |
11 | hashword(), hashlittle(), hashlittle2(), hashbig(), mix(), and final() | |
12 | are externally useful functions. Routines to test the hash are included | |
13 | if SELF_TEST is defined. You can use this free for any purpose. It's in | |
14 | the public domain. It has no warranty. | |
15 | ||
16 | You probably want to use hashlittle(). hashlittle() and hashbig() | |
c5315881 | 17 | hash byte arrays. hashlittle() is faster than hashbig() on |
87d2c1ff LP |
18 | little-endian machines. Intel and AMD are little-endian machines. |
19 | On second thought, you probably want hashlittle2(), which is identical to | |
20 | hashlittle() except it returns two 32-bit hashes for the price of one. | |
21 | You could implement hashbig2() if you wanted but I haven't bothered here. | |
22 | ||
23 | If you want to find a hash of, say, exactly 7 integers, do | |
24 | a = i1; b = i2; c = i3; | |
25 | mix(a,b,c); | |
26 | a += i4; b += i5; c += i6; | |
27 | mix(a,b,c); | |
28 | a += i7; | |
29 | final(a,b,c); | |
30 | then use c as the hash value. If you have a variable length array of | |
31 | 4-byte integers to hash, use hashword(). If you have a byte array (like | |
32 | a character string), use hashlittle(). If you have several byte arrays, or | |
33 | a mix of things, see the comments above hashlittle(). | |
34 | ||
35 | Why is this so big? I read 12 bytes at a time into 3 4-byte integers, | |
36 | then mix those integers. This is fast (you can do a lot more thorough | |
37 | mixing with 12*3 instructions on 3 integers than you can with 3 instructions | |
38 | on 1 byte), but shoehorning those bytes into integers efficiently is messy. | |
39 | ------------------------------------------------------------------------------- | |
40 | */ | |
41 | /* #define SELF_TEST 1 */ | |
42 | ||
43 | #include <stdio.h> /* defines printf for tests */ | |
44 | #include <time.h> /* defines time_t for timings in the test */ | |
45 | #include <stdint.h> /* defines uint32_t etc */ | |
46 | #include <sys/param.h> /* attempt to define endianness */ | |
47 | #ifdef linux | |
48 | # include <endian.h> /* attempt to define endianness */ | |
49 | #endif | |
50 | ||
51 | /* | |
52 | * My best guess at if you are big-endian or little-endian. This may | |
53 | * need adjustment. | |
54 | */ | |
55 | #if (defined(__BYTE_ORDER) && defined(__LITTLE_ENDIAN) && \ | |
56 | __BYTE_ORDER == __LITTLE_ENDIAN) || \ | |
57 | (defined(i386) || defined(__i386__) || defined(__i486__) || \ | |
58 | defined(__i586__) || defined(__i686__) || defined(vax) || defined(MIPSEL)) | |
59 | # define HASH_LITTLE_ENDIAN 1 | |
60 | # define HASH_BIG_ENDIAN 0 | |
61 | #elif (defined(__BYTE_ORDER) && defined(__BIG_ENDIAN) && \ | |
62 | __BYTE_ORDER == __BIG_ENDIAN) || \ | |
63 | (defined(sparc) || defined(POWERPC) || defined(mc68000) || defined(sel)) | |
64 | # define HASH_LITTLE_ENDIAN 0 | |
65 | # define HASH_BIG_ENDIAN 1 | |
66 | #else | |
67 | # define HASH_LITTLE_ENDIAN 0 | |
68 | # define HASH_BIG_ENDIAN 0 | |
69 | #endif | |
70 | ||
71 | #define hashsize(n) ((uint32_t)1<<(n)) | |
72 | #define hashmask(n) (hashsize(n)-1) | |
73 | #define rot(x,k) (((x)<<(k)) | ((x)>>(32-(k)))) | |
74 | ||
75 | /* | |
76 | ------------------------------------------------------------------------------- | |
77 | mix -- mix 3 32-bit values reversibly. | |
78 | ||
79 | This is reversible, so any information in (a,b,c) before mix() is | |
80 | still in (a,b,c) after mix(). | |
81 | ||
82 | If four pairs of (a,b,c) inputs are run through mix(), or through | |
83 | mix() in reverse, there are at least 32 bits of the output that | |
84 | are sometimes the same for one pair and different for another pair. | |
85 | This was tested for: | |
86 | * pairs that differed by one bit, by two bits, in any combination | |
87 | of top bits of (a,b,c), or in any combination of bottom bits of | |
88 | (a,b,c). | |
89 | * "differ" is defined as +, -, ^, or ~^. For + and -, I transformed | |
90 | the output delta to a Gray code (a^(a>>1)) so a string of 1's (as | |
91 | is commonly produced by subtraction) look like a single 1-bit | |
92 | difference. | |
93 | * the base values were pseudorandom, all zero but one bit set, or | |
94 | all zero plus a counter that starts at zero. | |
95 | ||
96 | Some k values for my "a-=c; a^=rot(c,k); c+=b;" arrangement that | |
97 | satisfy this are | |
98 | 4 6 8 16 19 4 | |
99 | 9 15 3 18 27 15 | |
100 | 14 9 3 7 17 3 | |
101 | Well, "9 15 3 18 27 15" didn't quite get 32 bits diffing | |
102 | for "differ" defined as + with a one-bit base and a two-bit delta. I | |
103 | used http://burtleburtle.net/bob/hash/avalanche.html to choose | |
104 | the operations, constants, and arrangements of the variables. | |
105 | ||
106 | This does not achieve avalanche. There are input bits of (a,b,c) | |
107 | that fail to affect some output bits of (a,b,c), especially of a. The | |
108 | most thoroughly mixed value is c, but it doesn't really even achieve | |
109 | avalanche in c. | |
110 | ||
111 | This allows some parallelism. Read-after-writes are good at doubling | |
112 | the number of bits affected, so the goal of mixing pulls in the opposite | |
113 | direction as the goal of parallelism. I did what I could. Rotates | |
114 | seem to cost as much as shifts on every machine I could lay my hands | |
115 | on, and rotates are much kinder to the top and bottom bits, so I used | |
116 | rotates. | |
117 | ------------------------------------------------------------------------------- | |
118 | */ | |
119 | #define mix(a,b,c) \ | |
120 | { \ | |
121 | a -= c; a ^= rot(c, 4); c += b; \ | |
122 | b -= a; b ^= rot(a, 6); a += c; \ | |
123 | c -= b; c ^= rot(b, 8); b += a; \ | |
124 | a -= c; a ^= rot(c,16); c += b; \ | |
125 | b -= a; b ^= rot(a,19); a += c; \ | |
126 | c -= b; c ^= rot(b, 4); b += a; \ | |
127 | } | |
128 | ||
129 | /* | |
130 | ------------------------------------------------------------------------------- | |
131 | final -- final mixing of 3 32-bit values (a,b,c) into c | |
132 | ||
133 | Pairs of (a,b,c) values differing in only a few bits will usually | |
134 | produce values of c that look totally different. This was tested for | |
135 | * pairs that differed by one bit, by two bits, in any combination | |
136 | of top bits of (a,b,c), or in any combination of bottom bits of | |
137 | (a,b,c). | |
138 | * "differ" is defined as +, -, ^, or ~^. For + and -, I transformed | |
139 | the output delta to a Gray code (a^(a>>1)) so a string of 1's (as | |
140 | is commonly produced by subtraction) look like a single 1-bit | |
141 | difference. | |
142 | * the base values were pseudorandom, all zero but one bit set, or | |
143 | all zero plus a counter that starts at zero. | |
144 | ||
145 | These constants passed: | |
146 | 14 11 25 16 4 14 24 | |
147 | 12 14 25 16 4 14 24 | |
148 | and these came close: | |
149 | 4 8 15 26 3 22 24 | |
150 | 10 8 15 26 3 22 24 | |
151 | 11 8 15 26 3 22 24 | |
152 | ------------------------------------------------------------------------------- | |
153 | */ | |
154 | #define final(a,b,c) \ | |
155 | { \ | |
156 | c ^= b; c -= rot(b,14); \ | |
157 | a ^= c; a -= rot(c,11); \ | |
158 | b ^= a; b -= rot(a,25); \ | |
159 | c ^= b; c -= rot(b,16); \ | |
160 | a ^= c; a -= rot(c,4); \ | |
161 | b ^= a; b -= rot(a,14); \ | |
162 | c ^= b; c -= rot(b,24); \ | |
163 | } | |
164 | ||
165 | /* | |
166 | -------------------------------------------------------------------- | |
167 | This works on all machines. To be useful, it requires | |
168 | -- that the key be an array of uint32_t's, and | |
169 | -- that the length be the number of uint32_t's in the key | |
170 | ||
171 | The function hashword() is identical to hashlittle() on little-endian | |
172 | machines, and identical to hashbig() on big-endian machines, | |
173 | except that the length has to be measured in uint32_ts rather than in | |
174 | bytes. hashlittle() is more complicated than hashword() only because | |
175 | hashlittle() has to dance around fitting the key bytes into registers. | |
176 | -------------------------------------------------------------------- | |
177 | */ | |
178 | uint32_t jenkins_hashword( | |
179 | const uint32_t *k, /* the key, an array of uint32_t values */ | |
180 | size_t length, /* the length of the key, in uint32_ts */ | |
181 | uint32_t initval) /* the previous hash, or an arbitrary value */ | |
182 | { | |
183 | uint32_t a,b,c; | |
184 | ||
185 | /* Set up the internal state */ | |
186 | a = b = c = 0xdeadbeef + (((uint32_t)length)<<2) + initval; | |
187 | ||
188 | /*------------------------------------------------- handle most of the key */ | |
189 | while (length > 3) | |
190 | { | |
191 | a += k[0]; | |
192 | b += k[1]; | |
193 | c += k[2]; | |
194 | mix(a,b,c); | |
195 | length -= 3; | |
196 | k += 3; | |
197 | } | |
198 | ||
199 | /*------------------------------------------- handle the last 3 uint32_t's */ | |
200 | switch(length) /* all the case statements fall through */ | |
201 | { | |
202 | case 3 : c+=k[2]; | |
203 | case 2 : b+=k[1]; | |
204 | case 1 : a+=k[0]; | |
205 | final(a,b,c); | |
206 | case 0: /* case 0: nothing left to add */ | |
207 | break; | |
208 | } | |
209 | /*------------------------------------------------------ report the result */ | |
210 | return c; | |
211 | } | |
212 | ||
213 | ||
214 | /* | |
215 | -------------------------------------------------------------------- | |
216 | hashword2() -- same as hashword(), but take two seeds and return two | |
217 | 32-bit values. pc and pb must both be nonnull, and *pc and *pb must | |
218 | both be initialized with seeds. If you pass in (*pb)==0, the output | |
219 | (*pc) will be the same as the return value from hashword(). | |
220 | -------------------------------------------------------------------- | |
221 | */ | |
222 | void jenkins_hashword2 ( | |
223 | const uint32_t *k, /* the key, an array of uint32_t values */ | |
224 | size_t length, /* the length of the key, in uint32_ts */ | |
225 | uint32_t *pc, /* IN: seed OUT: primary hash value */ | |
226 | uint32_t *pb) /* IN: more seed OUT: secondary hash value */ | |
227 | { | |
228 | uint32_t a,b,c; | |
229 | ||
230 | /* Set up the internal state */ | |
231 | a = b = c = 0xdeadbeef + ((uint32_t)(length<<2)) + *pc; | |
232 | c += *pb; | |
233 | ||
234 | /*------------------------------------------------- handle most of the key */ | |
235 | while (length > 3) | |
236 | { | |
237 | a += k[0]; | |
238 | b += k[1]; | |
239 | c += k[2]; | |
240 | mix(a,b,c); | |
241 | length -= 3; | |
242 | k += 3; | |
243 | } | |
244 | ||
245 | /*------------------------------------------- handle the last 3 uint32_t's */ | |
246 | switch(length) /* all the case statements fall through */ | |
247 | { | |
248 | case 3 : c+=k[2]; | |
249 | case 2 : b+=k[1]; | |
250 | case 1 : a+=k[0]; | |
251 | final(a,b,c); | |
252 | case 0: /* case 0: nothing left to add */ | |
253 | break; | |
254 | } | |
255 | /*------------------------------------------------------ report the result */ | |
256 | *pc=c; *pb=b; | |
257 | } | |
258 | ||
259 | ||
260 | /* | |
261 | ------------------------------------------------------------------------------- | |
262 | hashlittle() -- hash a variable-length key into a 32-bit value | |
263 | k : the key (the unaligned variable-length array of bytes) | |
264 | length : the length of the key, counting by bytes | |
265 | initval : can be any 4-byte value | |
266 | Returns a 32-bit value. Every bit of the key affects every bit of | |
267 | the return value. Two keys differing by one or two bits will have | |
268 | totally different hash values. | |
269 | ||
270 | The best hash table sizes are powers of 2. There is no need to do | |
271 | mod a prime (mod is sooo slow!). If you need less than 32 bits, | |
272 | use a bitmask. For example, if you need only 10 bits, do | |
273 | h = (h & hashmask(10)); | |
274 | In which case, the hash table should have hashsize(10) elements. | |
275 | ||
276 | If you are hashing n strings (uint8_t **)k, do it like this: | |
277 | for (i=0, h=0; i<n; ++i) h = hashlittle( k[i], len[i], h); | |
278 | ||
279 | By Bob Jenkins, 2006. bob_jenkins@burtleburtle.net. You may use this | |
280 | code any way you wish, private, educational, or commercial. It's free. | |
281 | ||
282 | Use for hash table lookup, or anything where one collision in 2^^32 is | |
283 | acceptable. Do NOT use for cryptographic purposes. | |
284 | ------------------------------------------------------------------------------- | |
285 | */ | |
286 | ||
287 | uint32_t jenkins_hashlittle( const void *key, size_t length, uint32_t initval) | |
288 | { | |
289 | uint32_t a,b,c; /* internal state */ | |
290 | union { const void *ptr; size_t i; } u; /* needed for Mac Powerbook G4 */ | |
291 | ||
292 | /* Set up the internal state */ | |
293 | a = b = c = 0xdeadbeef + ((uint32_t)length) + initval; | |
294 | ||
295 | u.ptr = key; | |
296 | if (HASH_LITTLE_ENDIAN && ((u.i & 0x3) == 0)) { | |
297 | const uint32_t *k = (const uint32_t *)key; /* read 32-bit chunks */ | |
298 | ||
299 | /*------ all but last block: aligned reads and affect 32 bits of (a,b,c) */ | |
300 | while (length > 12) | |
301 | { | |
302 | a += k[0]; | |
303 | b += k[1]; | |
304 | c += k[2]; | |
305 | mix(a,b,c); | |
306 | length -= 12; | |
307 | k += 3; | |
308 | } | |
309 | ||
310 | /*----------------------------- handle the last (probably partial) block */ | |
311 | /* | |
312 | * "k[2]&0xffffff" actually reads beyond the end of the string, but | |
313 | * then masks off the part it's not allowed to read. Because the | |
314 | * string is aligned, the masked-off tail is in the same word as the | |
315 | * rest of the string. Every machine with memory protection I've seen | |
316 | * does it on word boundaries, so is OK with this. But VALGRIND will | |
317 | * still catch it and complain. The masking trick does make the hash | |
49f43d5f | 318 | * noticeably faster for short strings (like English words). |
87d2c1ff LP |
319 | */ |
320 | #ifndef VALGRIND | |
321 | ||
322 | switch(length) | |
323 | { | |
324 | case 12: c+=k[2]; b+=k[1]; a+=k[0]; break; | |
325 | case 11: c+=k[2]&0xffffff; b+=k[1]; a+=k[0]; break; | |
326 | case 10: c+=k[2]&0xffff; b+=k[1]; a+=k[0]; break; | |
327 | case 9 : c+=k[2]&0xff; b+=k[1]; a+=k[0]; break; | |
328 | case 8 : b+=k[1]; a+=k[0]; break; | |
329 | case 7 : b+=k[1]&0xffffff; a+=k[0]; break; | |
330 | case 6 : b+=k[1]&0xffff; a+=k[0]; break; | |
331 | case 5 : b+=k[1]&0xff; a+=k[0]; break; | |
332 | case 4 : a+=k[0]; break; | |
333 | case 3 : a+=k[0]&0xffffff; break; | |
334 | case 2 : a+=k[0]&0xffff; break; | |
335 | case 1 : a+=k[0]&0xff; break; | |
336 | case 0 : return c; /* zero length strings require no mixing */ | |
337 | } | |
338 | ||
339 | #else /* make valgrind happy */ | |
87d2c1ff | 340 | { |
1b4bb4fd ZJS |
341 | const uint8_t *k8 = (const uint8_t *) k; |
342 | ||
343 | switch(length) | |
344 | { | |
345 | case 12: c+=k[2]; b+=k[1]; a+=k[0]; break; | |
346 | case 11: c+=((uint32_t)k8[10])<<16; /* fall through */ | |
347 | case 10: c+=((uint32_t)k8[9])<<8; /* fall through */ | |
348 | case 9 : c+=k8[8]; /* fall through */ | |
349 | case 8 : b+=k[1]; a+=k[0]; break; | |
350 | case 7 : b+=((uint32_t)k8[6])<<16; /* fall through */ | |
351 | case 6 : b+=((uint32_t)k8[5])<<8; /* fall through */ | |
352 | case 5 : b+=k8[4]; /* fall through */ | |
353 | case 4 : a+=k[0]; break; | |
354 | case 3 : a+=((uint32_t)k8[2])<<16; /* fall through */ | |
355 | case 2 : a+=((uint32_t)k8[1])<<8; /* fall through */ | |
356 | case 1 : a+=k8[0]; break; | |
357 | case 0 : return c; | |
358 | } | |
87d2c1ff LP |
359 | } |
360 | ||
361 | #endif /* !valgrind */ | |
362 | ||
363 | } else if (HASH_LITTLE_ENDIAN && ((u.i & 0x1) == 0)) { | |
364 | const uint16_t *k = (const uint16_t *)key; /* read 16-bit chunks */ | |
365 | const uint8_t *k8; | |
366 | ||
367 | /*--------------- all but last block: aligned reads and different mixing */ | |
368 | while (length > 12) | |
369 | { | |
370 | a += k[0] + (((uint32_t)k[1])<<16); | |
371 | b += k[2] + (((uint32_t)k[3])<<16); | |
372 | c += k[4] + (((uint32_t)k[5])<<16); | |
373 | mix(a,b,c); | |
374 | length -= 12; | |
375 | k += 6; | |
376 | } | |
377 | ||
378 | /*----------------------------- handle the last (probably partial) block */ | |
379 | k8 = (const uint8_t *)k; | |
380 | switch(length) | |
381 | { | |
382 | case 12: c+=k[4]+(((uint32_t)k[5])<<16); | |
383 | b+=k[2]+(((uint32_t)k[3])<<16); | |
384 | a+=k[0]+(((uint32_t)k[1])<<16); | |
385 | break; | |
386 | case 11: c+=((uint32_t)k8[10])<<16; /* fall through */ | |
387 | case 10: c+=k[4]; | |
388 | b+=k[2]+(((uint32_t)k[3])<<16); | |
389 | a+=k[0]+(((uint32_t)k[1])<<16); | |
390 | break; | |
391 | case 9 : c+=k8[8]; /* fall through */ | |
392 | case 8 : b+=k[2]+(((uint32_t)k[3])<<16); | |
393 | a+=k[0]+(((uint32_t)k[1])<<16); | |
394 | break; | |
395 | case 7 : b+=((uint32_t)k8[6])<<16; /* fall through */ | |
396 | case 6 : b+=k[2]; | |
397 | a+=k[0]+(((uint32_t)k[1])<<16); | |
398 | break; | |
399 | case 5 : b+=k8[4]; /* fall through */ | |
400 | case 4 : a+=k[0]+(((uint32_t)k[1])<<16); | |
401 | break; | |
402 | case 3 : a+=((uint32_t)k8[2])<<16; /* fall through */ | |
403 | case 2 : a+=k[0]; | |
404 | break; | |
405 | case 1 : a+=k8[0]; | |
406 | break; | |
407 | case 0 : return c; /* zero length requires no mixing */ | |
408 | } | |
409 | ||
410 | } else { /* need to read the key one byte at a time */ | |
411 | const uint8_t *k = (const uint8_t *)key; | |
412 | ||
413 | /*--------------- all but the last block: affect some 32 bits of (a,b,c) */ | |
414 | while (length > 12) | |
415 | { | |
416 | a += k[0]; | |
417 | a += ((uint32_t)k[1])<<8; | |
418 | a += ((uint32_t)k[2])<<16; | |
419 | a += ((uint32_t)k[3])<<24; | |
420 | b += k[4]; | |
421 | b += ((uint32_t)k[5])<<8; | |
422 | b += ((uint32_t)k[6])<<16; | |
423 | b += ((uint32_t)k[7])<<24; | |
424 | c += k[8]; | |
425 | c += ((uint32_t)k[9])<<8; | |
426 | c += ((uint32_t)k[10])<<16; | |
427 | c += ((uint32_t)k[11])<<24; | |
428 | mix(a,b,c); | |
429 | length -= 12; | |
430 | k += 12; | |
431 | } | |
432 | ||
433 | /*-------------------------------- last block: affect all 32 bits of (c) */ | |
434 | switch(length) /* all the case statements fall through */ | |
435 | { | |
436 | case 12: c+=((uint32_t)k[11])<<24; | |
437 | case 11: c+=((uint32_t)k[10])<<16; | |
438 | case 10: c+=((uint32_t)k[9])<<8; | |
439 | case 9 : c+=k[8]; | |
440 | case 8 : b+=((uint32_t)k[7])<<24; | |
441 | case 7 : b+=((uint32_t)k[6])<<16; | |
442 | case 6 : b+=((uint32_t)k[5])<<8; | |
443 | case 5 : b+=k[4]; | |
444 | case 4 : a+=((uint32_t)k[3])<<24; | |
445 | case 3 : a+=((uint32_t)k[2])<<16; | |
446 | case 2 : a+=((uint32_t)k[1])<<8; | |
447 | case 1 : a+=k[0]; | |
448 | break; | |
449 | case 0 : return c; | |
450 | } | |
451 | } | |
452 | ||
453 | final(a,b,c); | |
454 | return c; | |
455 | } | |
456 | ||
457 | ||
458 | /* | |
459 | * hashlittle2: return 2 32-bit hash values | |
460 | * | |
461 | * This is identical to hashlittle(), except it returns two 32-bit hash | |
462 | * values instead of just one. This is good enough for hash table | |
463 | * lookup with 2^^64 buckets, or if you want a second hash if you're not | |
464 | * happy with the first, or if you want a probably-unique 64-bit ID for | |
465 | * the key. *pc is better mixed than *pb, so use *pc first. If you want | |
466 | * a 64-bit value do something like "*pc + (((uint64_t)*pb)<<32)". | |
467 | */ | |
468 | void jenkins_hashlittle2( | |
469 | const void *key, /* the key to hash */ | |
470 | size_t length, /* length of the key */ | |
471 | uint32_t *pc, /* IN: primary initval, OUT: primary hash */ | |
472 | uint32_t *pb) /* IN: secondary initval, OUT: secondary hash */ | |
473 | { | |
474 | uint32_t a,b,c; /* internal state */ | |
475 | union { const void *ptr; size_t i; } u; /* needed for Mac Powerbook G4 */ | |
476 | ||
477 | /* Set up the internal state */ | |
478 | a = b = c = 0xdeadbeef + ((uint32_t)length) + *pc; | |
479 | c += *pb; | |
480 | ||
481 | u.ptr = key; | |
482 | if (HASH_LITTLE_ENDIAN && ((u.i & 0x3) == 0)) { | |
483 | const uint32_t *k = (const uint32_t *)key; /* read 32-bit chunks */ | |
484 | ||
485 | /*------ all but last block: aligned reads and affect 32 bits of (a,b,c) */ | |
486 | while (length > 12) | |
487 | { | |
488 | a += k[0]; | |
489 | b += k[1]; | |
490 | c += k[2]; | |
491 | mix(a,b,c); | |
492 | length -= 12; | |
493 | k += 3; | |
494 | } | |
495 | ||
496 | /*----------------------------- handle the last (probably partial) block */ | |
497 | /* | |
498 | * "k[2]&0xffffff" actually reads beyond the end of the string, but | |
499 | * then masks off the part it's not allowed to read. Because the | |
500 | * string is aligned, the masked-off tail is in the same word as the | |
501 | * rest of the string. Every machine with memory protection I've seen | |
502 | * does it on word boundaries, so is OK with this. But VALGRIND will | |
503 | * still catch it and complain. The masking trick does make the hash | |
49f43d5f | 504 | * noticeably faster for short strings (like English words). |
87d2c1ff LP |
505 | */ |
506 | #ifndef VALGRIND | |
507 | ||
508 | switch(length) | |
509 | { | |
510 | case 12: c+=k[2]; b+=k[1]; a+=k[0]; break; | |
511 | case 11: c+=k[2]&0xffffff; b+=k[1]; a+=k[0]; break; | |
512 | case 10: c+=k[2]&0xffff; b+=k[1]; a+=k[0]; break; | |
513 | case 9 : c+=k[2]&0xff; b+=k[1]; a+=k[0]; break; | |
514 | case 8 : b+=k[1]; a+=k[0]; break; | |
515 | case 7 : b+=k[1]&0xffffff; a+=k[0]; break; | |
516 | case 6 : b+=k[1]&0xffff; a+=k[0]; break; | |
517 | case 5 : b+=k[1]&0xff; a+=k[0]; break; | |
518 | case 4 : a+=k[0]; break; | |
519 | case 3 : a+=k[0]&0xffffff; break; | |
520 | case 2 : a+=k[0]&0xffff; break; | |
521 | case 1 : a+=k[0]&0xff; break; | |
522 | case 0 : *pc=c; *pb=b; return; /* zero length strings require no mixing */ | |
523 | } | |
524 | ||
525 | #else /* make valgrind happy */ | |
526 | ||
87d2c1ff | 527 | { |
1b4bb4fd ZJS |
528 | const uint8_t *k8 = (const uint8_t *)k; |
529 | switch(length) | |
530 | { | |
531 | case 12: c+=k[2]; b+=k[1]; a+=k[0]; break; | |
532 | case 11: c+=((uint32_t)k8[10])<<16; /* fall through */ | |
533 | case 10: c+=((uint32_t)k8[9])<<8; /* fall through */ | |
534 | case 9 : c+=k8[8]; /* fall through */ | |
535 | case 8 : b+=k[1]; a+=k[0]; break; | |
536 | case 7 : b+=((uint32_t)k8[6])<<16; /* fall through */ | |
537 | case 6 : b+=((uint32_t)k8[5])<<8; /* fall through */ | |
538 | case 5 : b+=k8[4]; /* fall through */ | |
539 | case 4 : a+=k[0]; break; | |
540 | case 3 : a+=((uint32_t)k8[2])<<16; /* fall through */ | |
541 | case 2 : a+=((uint32_t)k8[1])<<8; /* fall through */ | |
542 | case 1 : a+=k8[0]; break; | |
543 | case 0 : *pc=c; *pb=b; return; /* zero length strings require no mixing */ | |
544 | } | |
87d2c1ff LP |
545 | } |
546 | ||
547 | #endif /* !valgrind */ | |
548 | ||
549 | } else if (HASH_LITTLE_ENDIAN && ((u.i & 0x1) == 0)) { | |
550 | const uint16_t *k = (const uint16_t *)key; /* read 16-bit chunks */ | |
551 | const uint8_t *k8; | |
552 | ||
553 | /*--------------- all but last block: aligned reads and different mixing */ | |
554 | while (length > 12) | |
555 | { | |
556 | a += k[0] + (((uint32_t)k[1])<<16); | |
557 | b += k[2] + (((uint32_t)k[3])<<16); | |
558 | c += k[4] + (((uint32_t)k[5])<<16); | |
559 | mix(a,b,c); | |
560 | length -= 12; | |
561 | k += 6; | |
562 | } | |
563 | ||
564 | /*----------------------------- handle the last (probably partial) block */ | |
565 | k8 = (const uint8_t *)k; | |
566 | switch(length) | |
567 | { | |
568 | case 12: c+=k[4]+(((uint32_t)k[5])<<16); | |
569 | b+=k[2]+(((uint32_t)k[3])<<16); | |
570 | a+=k[0]+(((uint32_t)k[1])<<16); | |
571 | break; | |
572 | case 11: c+=((uint32_t)k8[10])<<16; /* fall through */ | |
573 | case 10: c+=k[4]; | |
574 | b+=k[2]+(((uint32_t)k[3])<<16); | |
575 | a+=k[0]+(((uint32_t)k[1])<<16); | |
576 | break; | |
577 | case 9 : c+=k8[8]; /* fall through */ | |
578 | case 8 : b+=k[2]+(((uint32_t)k[3])<<16); | |
579 | a+=k[0]+(((uint32_t)k[1])<<16); | |
580 | break; | |
581 | case 7 : b+=((uint32_t)k8[6])<<16; /* fall through */ | |
582 | case 6 : b+=k[2]; | |
583 | a+=k[0]+(((uint32_t)k[1])<<16); | |
584 | break; | |
585 | case 5 : b+=k8[4]; /* fall through */ | |
586 | case 4 : a+=k[0]+(((uint32_t)k[1])<<16); | |
587 | break; | |
588 | case 3 : a+=((uint32_t)k8[2])<<16; /* fall through */ | |
589 | case 2 : a+=k[0]; | |
590 | break; | |
591 | case 1 : a+=k8[0]; | |
592 | break; | |
593 | case 0 : *pc=c; *pb=b; return; /* zero length strings require no mixing */ | |
594 | } | |
595 | ||
596 | } else { /* need to read the key one byte at a time */ | |
597 | const uint8_t *k = (const uint8_t *)key; | |
598 | ||
599 | /*--------------- all but the last block: affect some 32 bits of (a,b,c) */ | |
600 | while (length > 12) | |
601 | { | |
602 | a += k[0]; | |
603 | a += ((uint32_t)k[1])<<8; | |
604 | a += ((uint32_t)k[2])<<16; | |
605 | a += ((uint32_t)k[3])<<24; | |
606 | b += k[4]; | |
607 | b += ((uint32_t)k[5])<<8; | |
608 | b += ((uint32_t)k[6])<<16; | |
609 | b += ((uint32_t)k[7])<<24; | |
610 | c += k[8]; | |
611 | c += ((uint32_t)k[9])<<8; | |
612 | c += ((uint32_t)k[10])<<16; | |
613 | c += ((uint32_t)k[11])<<24; | |
614 | mix(a,b,c); | |
615 | length -= 12; | |
616 | k += 12; | |
617 | } | |
618 | ||
619 | /*-------------------------------- last block: affect all 32 bits of (c) */ | |
620 | switch(length) /* all the case statements fall through */ | |
621 | { | |
622 | case 12: c+=((uint32_t)k[11])<<24; | |
623 | case 11: c+=((uint32_t)k[10])<<16; | |
624 | case 10: c+=((uint32_t)k[9])<<8; | |
625 | case 9 : c+=k[8]; | |
626 | case 8 : b+=((uint32_t)k[7])<<24; | |
627 | case 7 : b+=((uint32_t)k[6])<<16; | |
628 | case 6 : b+=((uint32_t)k[5])<<8; | |
629 | case 5 : b+=k[4]; | |
630 | case 4 : a+=((uint32_t)k[3])<<24; | |
631 | case 3 : a+=((uint32_t)k[2])<<16; | |
632 | case 2 : a+=((uint32_t)k[1])<<8; | |
633 | case 1 : a+=k[0]; | |
634 | break; | |
635 | case 0 : *pc=c; *pb=b; return; /* zero length strings require no mixing */ | |
636 | } | |
637 | } | |
638 | ||
639 | final(a,b,c); | |
640 | *pc=c; *pb=b; | |
641 | } | |
642 | ||
643 | ||
644 | ||
645 | /* | |
646 | * hashbig(): | |
647 | * This is the same as hashword() on big-endian machines. It is different | |
648 | * from hashlittle() on all machines. hashbig() takes advantage of | |
649 | * big-endian byte ordering. | |
650 | */ | |
651 | uint32_t jenkins_hashbig( const void *key, size_t length, uint32_t initval) | |
652 | { | |
653 | uint32_t a,b,c; | |
654 | union { const void *ptr; size_t i; } u; /* to cast key to (size_t) happily */ | |
655 | ||
656 | /* Set up the internal state */ | |
657 | a = b = c = 0xdeadbeef + ((uint32_t)length) + initval; | |
658 | ||
659 | u.ptr = key; | |
660 | if (HASH_BIG_ENDIAN && ((u.i & 0x3) == 0)) { | |
661 | const uint32_t *k = (const uint32_t *)key; /* read 32-bit chunks */ | |
662 | ||
663 | /*------ all but last block: aligned reads and affect 32 bits of (a,b,c) */ | |
664 | while (length > 12) | |
665 | { | |
666 | a += k[0]; | |
667 | b += k[1]; | |
668 | c += k[2]; | |
669 | mix(a,b,c); | |
670 | length -= 12; | |
671 | k += 3; | |
672 | } | |
673 | ||
674 | /*----------------------------- handle the last (probably partial) block */ | |
675 | /* | |
676 | * "k[2]<<8" actually reads beyond the end of the string, but | |
677 | * then shifts out the part it's not allowed to read. Because the | |
678 | * string is aligned, the illegal read is in the same word as the | |
679 | * rest of the string. Every machine with memory protection I've seen | |
680 | * does it on word boundaries, so is OK with this. But VALGRIND will | |
681 | * still catch it and complain. The masking trick does make the hash | |
49f43d5f | 682 | * noticeably faster for short strings (like English words). |
87d2c1ff LP |
683 | */ |
684 | #ifndef VALGRIND | |
685 | ||
686 | switch(length) | |
687 | { | |
688 | case 12: c+=k[2]; b+=k[1]; a+=k[0]; break; | |
689 | case 11: c+=k[2]&0xffffff00; b+=k[1]; a+=k[0]; break; | |
690 | case 10: c+=k[2]&0xffff0000; b+=k[1]; a+=k[0]; break; | |
691 | case 9 : c+=k[2]&0xff000000; b+=k[1]; a+=k[0]; break; | |
692 | case 8 : b+=k[1]; a+=k[0]; break; | |
693 | case 7 : b+=k[1]&0xffffff00; a+=k[0]; break; | |
694 | case 6 : b+=k[1]&0xffff0000; a+=k[0]; break; | |
695 | case 5 : b+=k[1]&0xff000000; a+=k[0]; break; | |
696 | case 4 : a+=k[0]; break; | |
697 | case 3 : a+=k[0]&0xffffff00; break; | |
698 | case 2 : a+=k[0]&0xffff0000; break; | |
699 | case 1 : a+=k[0]&0xff000000; break; | |
700 | case 0 : return c; /* zero length strings require no mixing */ | |
701 | } | |
702 | ||
703 | #else /* make valgrind happy */ | |
704 | ||
87d2c1ff | 705 | { |
1b4bb4fd ZJS |
706 | const uint8_t *k8 = (const uint8_t *)k; |
707 | switch(length) /* all the case statements fall through */ | |
708 | { | |
709 | case 12: c+=k[2]; b+=k[1]; a+=k[0]; break; | |
710 | case 11: c+=((uint32_t)k8[10])<<8; /* fall through */ | |
711 | case 10: c+=((uint32_t)k8[9])<<16; /* fall through */ | |
712 | case 9 : c+=((uint32_t)k8[8])<<24; /* fall through */ | |
713 | case 8 : b+=k[1]; a+=k[0]; break; | |
714 | case 7 : b+=((uint32_t)k8[6])<<8; /* fall through */ | |
715 | case 6 : b+=((uint32_t)k8[5])<<16; /* fall through */ | |
716 | case 5 : b+=((uint32_t)k8[4])<<24; /* fall through */ | |
717 | case 4 : a+=k[0]; break; | |
718 | case 3 : a+=((uint32_t)k8[2])<<8; /* fall through */ | |
719 | case 2 : a+=((uint32_t)k8[1])<<16; /* fall through */ | |
720 | case 1 : a+=((uint32_t)k8[0])<<24; break; | |
721 | case 0 : return c; | |
722 | } | |
87d2c1ff LP |
723 | } |
724 | ||
725 | #endif /* !VALGRIND */ | |
726 | ||
727 | } else { /* need to read the key one byte at a time */ | |
728 | const uint8_t *k = (const uint8_t *)key; | |
729 | ||
730 | /*--------------- all but the last block: affect some 32 bits of (a,b,c) */ | |
731 | while (length > 12) | |
732 | { | |
733 | a += ((uint32_t)k[0])<<24; | |
734 | a += ((uint32_t)k[1])<<16; | |
735 | a += ((uint32_t)k[2])<<8; | |
736 | a += ((uint32_t)k[3]); | |
737 | b += ((uint32_t)k[4])<<24; | |
738 | b += ((uint32_t)k[5])<<16; | |
739 | b += ((uint32_t)k[6])<<8; | |
740 | b += ((uint32_t)k[7]); | |
741 | c += ((uint32_t)k[8])<<24; | |
742 | c += ((uint32_t)k[9])<<16; | |
743 | c += ((uint32_t)k[10])<<8; | |
744 | c += ((uint32_t)k[11]); | |
745 | mix(a,b,c); | |
746 | length -= 12; | |
747 | k += 12; | |
748 | } | |
749 | ||
750 | /*-------------------------------- last block: affect all 32 bits of (c) */ | |
751 | switch(length) /* all the case statements fall through */ | |
752 | { | |
753 | case 12: c+=k[11]; | |
754 | case 11: c+=((uint32_t)k[10])<<8; | |
755 | case 10: c+=((uint32_t)k[9])<<16; | |
756 | case 9 : c+=((uint32_t)k[8])<<24; | |
757 | case 8 : b+=k[7]; | |
758 | case 7 : b+=((uint32_t)k[6])<<8; | |
759 | case 6 : b+=((uint32_t)k[5])<<16; | |
760 | case 5 : b+=((uint32_t)k[4])<<24; | |
761 | case 4 : a+=k[3]; | |
762 | case 3 : a+=((uint32_t)k[2])<<8; | |
763 | case 2 : a+=((uint32_t)k[1])<<16; | |
764 | case 1 : a+=((uint32_t)k[0])<<24; | |
765 | break; | |
766 | case 0 : return c; | |
767 | } | |
768 | } | |
769 | ||
770 | final(a,b,c); | |
771 | return c; | |
772 | } | |
773 | ||
774 | ||
775 | #ifdef SELF_TEST | |
776 | ||
777 | /* used for timings */ | |
778 | void driver1() | |
779 | { | |
780 | uint8_t buf[256]; | |
781 | uint32_t i; | |
782 | uint32_t h=0; | |
783 | time_t a,z; | |
784 | ||
785 | time(&a); | |
786 | for (i=0; i<256; ++i) buf[i] = 'x'; | |
787 | for (i=0; i<1; ++i) | |
788 | { | |
789 | h = hashlittle(&buf[0],1,h); | |
790 | } | |
791 | time(&z); | |
792 | if (z-a > 0) printf("time %d %.8x\n", z-a, h); | |
793 | } | |
794 | ||
795 | /* check that every input bit changes every output bit half the time */ | |
796 | #define HASHSTATE 1 | |
797 | #define HASHLEN 1 | |
798 | #define MAXPAIR 60 | |
799 | #define MAXLEN 70 | |
800 | void driver2() | |
801 | { | |
802 | uint8_t qa[MAXLEN+1], qb[MAXLEN+2], *a = &qa[0], *b = &qb[1]; | |
803 | uint32_t c[HASHSTATE], d[HASHSTATE], i=0, j=0, k, l, m=0, z; | |
804 | uint32_t e[HASHSTATE],f[HASHSTATE],g[HASHSTATE],h[HASHSTATE]; | |
805 | uint32_t x[HASHSTATE],y[HASHSTATE]; | |
806 | uint32_t hlen; | |
807 | ||
808 | printf("No more than %d trials should ever be needed \n",MAXPAIR/2); | |
809 | for (hlen=0; hlen < MAXLEN; ++hlen) | |
810 | { | |
811 | z=0; | |
812 | for (i=0; i<hlen; ++i) /*----------------------- for each input byte, */ | |
813 | { | |
814 | for (j=0; j<8; ++j) /*------------------------ for each input bit, */ | |
815 | { | |
816 | for (m=1; m<8; ++m) /*------------ for serveral possible initvals, */ | |
817 | { | |
818 | for (l=0; l<HASHSTATE; ++l) | |
819 | e[l]=f[l]=g[l]=h[l]=x[l]=y[l]=~((uint32_t)0); | |
820 | ||
821 | /*---- check that every output bit is affected by that input bit */ | |
822 | for (k=0; k<MAXPAIR; k+=2) | |
823 | { | |
824 | uint32_t finished=1; | |
825 | /* keys have one bit different */ | |
826 | for (l=0; l<hlen+1; ++l) {a[l] = b[l] = (uint8_t)0;} | |
827 | /* have a and b be two keys differing in only one bit */ | |
828 | a[i] ^= (k<<j); | |
829 | a[i] ^= (k>>(8-j)); | |
830 | c[0] = hashlittle(a, hlen, m); | |
831 | b[i] ^= ((k+1)<<j); | |
832 | b[i] ^= ((k+1)>>(8-j)); | |
833 | d[0] = hashlittle(b, hlen, m); | |
834 | /* check every bit is 1, 0, set, and not set at least once */ | |
835 | for (l=0; l<HASHSTATE; ++l) | |
836 | { | |
837 | e[l] &= (c[l]^d[l]); | |
838 | f[l] &= ~(c[l]^d[l]); | |
839 | g[l] &= c[l]; | |
840 | h[l] &= ~c[l]; | |
841 | x[l] &= d[l]; | |
842 | y[l] &= ~d[l]; | |
843 | if (e[l]|f[l]|g[l]|h[l]|x[l]|y[l]) finished=0; | |
844 | } | |
845 | if (finished) break; | |
846 | } | |
847 | if (k>z) z=k; | |
848 | if (k==MAXPAIR) | |
849 | { | |
850 | printf("Some bit didn't change: "); | |
851 | printf("%.8x %.8x %.8x %.8x %.8x %.8x ", | |
852 | e[0],f[0],g[0],h[0],x[0],y[0]); | |
853 | printf("i %d j %d m %d len %d\n", i, j, m, hlen); | |
854 | } | |
855 | if (z==MAXPAIR) goto done; | |
856 | } | |
857 | } | |
858 | } | |
859 | done: | |
860 | if (z < MAXPAIR) | |
861 | { | |
862 | printf("Mix success %2d bytes %2d initvals ",i,m); | |
863 | printf("required %d trials\n", z/2); | |
864 | } | |
865 | } | |
866 | printf("\n"); | |
867 | } | |
868 | ||
869 | /* Check for reading beyond the end of the buffer and alignment problems */ | |
870 | void driver3() | |
871 | { | |
872 | uint8_t buf[MAXLEN+20], *b; | |
873 | uint32_t len; | |
874 | uint8_t q[] = "This is the time for all good men to come to the aid of their country..."; | |
875 | uint32_t h; | |
876 | uint8_t qq[] = "xThis is the time for all good men to come to the aid of their country..."; | |
877 | uint32_t i; | |
878 | uint8_t qqq[] = "xxThis is the time for all good men to come to the aid of their country..."; | |
879 | uint32_t j; | |
880 | uint8_t qqqq[] = "xxxThis is the time for all good men to come to the aid of their country..."; | |
881 | uint32_t ref,x,y; | |
882 | uint8_t *p; | |
883 | ||
884 | printf("Endianness. These lines should all be the same (for values filled in):\n"); | |
885 | printf("%.8x %.8x %.8x\n", | |
886 | hashword((const uint32_t *)q, (sizeof(q)-1)/4, 13), | |
887 | hashword((const uint32_t *)q, (sizeof(q)-5)/4, 13), | |
888 | hashword((const uint32_t *)q, (sizeof(q)-9)/4, 13)); | |
889 | p = q; | |
890 | printf("%.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x\n", | |
891 | hashlittle(p, sizeof(q)-1, 13), hashlittle(p, sizeof(q)-2, 13), | |
892 | hashlittle(p, sizeof(q)-3, 13), hashlittle(p, sizeof(q)-4, 13), | |
893 | hashlittle(p, sizeof(q)-5, 13), hashlittle(p, sizeof(q)-6, 13), | |
894 | hashlittle(p, sizeof(q)-7, 13), hashlittle(p, sizeof(q)-8, 13), | |
895 | hashlittle(p, sizeof(q)-9, 13), hashlittle(p, sizeof(q)-10, 13), | |
896 | hashlittle(p, sizeof(q)-11, 13), hashlittle(p, sizeof(q)-12, 13)); | |
897 | p = &qq[1]; | |
898 | printf("%.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x\n", | |
899 | hashlittle(p, sizeof(q)-1, 13), hashlittle(p, sizeof(q)-2, 13), | |
900 | hashlittle(p, sizeof(q)-3, 13), hashlittle(p, sizeof(q)-4, 13), | |
901 | hashlittle(p, sizeof(q)-5, 13), hashlittle(p, sizeof(q)-6, 13), | |
902 | hashlittle(p, sizeof(q)-7, 13), hashlittle(p, sizeof(q)-8, 13), | |
903 | hashlittle(p, sizeof(q)-9, 13), hashlittle(p, sizeof(q)-10, 13), | |
904 | hashlittle(p, sizeof(q)-11, 13), hashlittle(p, sizeof(q)-12, 13)); | |
905 | p = &qqq[2]; | |
906 | printf("%.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x\n", | |
907 | hashlittle(p, sizeof(q)-1, 13), hashlittle(p, sizeof(q)-2, 13), | |
908 | hashlittle(p, sizeof(q)-3, 13), hashlittle(p, sizeof(q)-4, 13), | |
909 | hashlittle(p, sizeof(q)-5, 13), hashlittle(p, sizeof(q)-6, 13), | |
910 | hashlittle(p, sizeof(q)-7, 13), hashlittle(p, sizeof(q)-8, 13), | |
911 | hashlittle(p, sizeof(q)-9, 13), hashlittle(p, sizeof(q)-10, 13), | |
912 | hashlittle(p, sizeof(q)-11, 13), hashlittle(p, sizeof(q)-12, 13)); | |
913 | p = &qqqq[3]; | |
914 | printf("%.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x\n", | |
915 | hashlittle(p, sizeof(q)-1, 13), hashlittle(p, sizeof(q)-2, 13), | |
916 | hashlittle(p, sizeof(q)-3, 13), hashlittle(p, sizeof(q)-4, 13), | |
917 | hashlittle(p, sizeof(q)-5, 13), hashlittle(p, sizeof(q)-6, 13), | |
918 | hashlittle(p, sizeof(q)-7, 13), hashlittle(p, sizeof(q)-8, 13), | |
919 | hashlittle(p, sizeof(q)-9, 13), hashlittle(p, sizeof(q)-10, 13), | |
920 | hashlittle(p, sizeof(q)-11, 13), hashlittle(p, sizeof(q)-12, 13)); | |
921 | printf("\n"); | |
922 | ||
923 | /* check that hashlittle2 and hashlittle produce the same results */ | |
924 | i=47; j=0; | |
925 | hashlittle2(q, sizeof(q), &i, &j); | |
926 | if (hashlittle(q, sizeof(q), 47) != i) | |
927 | printf("hashlittle2 and hashlittle mismatch\n"); | |
928 | ||
929 | /* check that hashword2 and hashword produce the same results */ | |
930 | len = 0xdeadbeef; | |
931 | i=47, j=0; | |
932 | hashword2(&len, 1, &i, &j); | |
933 | if (hashword(&len, 1, 47) != i) | |
934 | printf("hashword2 and hashword mismatch %x %x\n", | |
935 | i, hashword(&len, 1, 47)); | |
936 | ||
937 | /* check hashlittle doesn't read before or after the ends of the string */ | |
938 | for (h=0, b=buf+1; h<8; ++h, ++b) | |
939 | { | |
940 | for (i=0; i<MAXLEN; ++i) | |
941 | { | |
942 | len = i; | |
943 | for (j=0; j<i; ++j) *(b+j)=0; | |
944 | ||
945 | /* these should all be equal */ | |
946 | ref = hashlittle(b, len, (uint32_t)1); | |
947 | *(b+i)=(uint8_t)~0; | |
948 | *(b-1)=(uint8_t)~0; | |
949 | x = hashlittle(b, len, (uint32_t)1); | |
950 | y = hashlittle(b, len, (uint32_t)1); | |
951 | if ((ref != x) || (ref != y)) | |
952 | { | |
953 | printf("alignment error: %.8x %.8x %.8x %d %d\n",ref,x,y, | |
954 | h, i); | |
955 | } | |
956 | } | |
957 | } | |
958 | } | |
959 | ||
960 | /* check for problems with nulls */ | |
961 | void driver4() | |
962 | { | |
963 | uint8_t buf[1]; | |
964 | uint32_t h,i,state[HASHSTATE]; | |
965 | ||
966 | ||
967 | buf[0] = ~0; | |
968 | for (i=0; i<HASHSTATE; ++i) state[i] = 1; | |
969 | printf("These should all be different\n"); | |
970 | for (i=0, h=0; i<8; ++i) | |
971 | { | |
972 | h = hashlittle(buf, 0, h); | |
973 | printf("%2ld 0-byte strings, hash is %.8x\n", i, h); | |
974 | } | |
975 | } | |
976 | ||
977 | void driver5() | |
978 | { | |
979 | uint32_t b,c; | |
980 | b=0, c=0, hashlittle2("", 0, &c, &b); | |
981 | printf("hash is %.8lx %.8lx\n", c, b); /* deadbeef deadbeef */ | |
982 | b=0xdeadbeef, c=0, hashlittle2("", 0, &c, &b); | |
983 | printf("hash is %.8lx %.8lx\n", c, b); /* bd5b7dde deadbeef */ | |
984 | b=0xdeadbeef, c=0xdeadbeef, hashlittle2("", 0, &c, &b); | |
985 | printf("hash is %.8lx %.8lx\n", c, b); /* 9c093ccd bd5b7dde */ | |
986 | b=0, c=0, hashlittle2("Four score and seven years ago", 30, &c, &b); | |
987 | printf("hash is %.8lx %.8lx\n", c, b); /* 17770551 ce7226e6 */ | |
988 | b=1, c=0, hashlittle2("Four score and seven years ago", 30, &c, &b); | |
989 | printf("hash is %.8lx %.8lx\n", c, b); /* e3607cae bd371de4 */ | |
990 | b=0, c=1, hashlittle2("Four score and seven years ago", 30, &c, &b); | |
991 | printf("hash is %.8lx %.8lx\n", c, b); /* cd628161 6cbea4b3 */ | |
992 | c = hashlittle("Four score and seven years ago", 30, 0); | |
993 | printf("hash is %.8lx\n", c); /* 17770551 */ | |
994 | c = hashlittle("Four score and seven years ago", 30, 1); | |
995 | printf("hash is %.8lx\n", c); /* cd628161 */ | |
996 | } | |
997 | ||
998 | ||
999 | int main() | |
1000 | { | |
1001 | driver1(); /* test that the key is hashed: used for timings */ | |
1002 | driver2(); /* test that whole key is hashed thoroughly */ | |
1003 | driver3(); /* test that nothing but the key is hashed */ | |
1004 | driver4(); /* test hashing multiple buffers (all buffers are null) */ | |
1005 | driver5(); /* test the hash against known vectors */ | |
1006 | return 1; | |
1007 | } | |
1008 | ||
1009 | #endif /* SELF_TEST */ |