Commit | Line | Data |
154e51a4 |
1 | /* $Header: hash.c,v 3.0.1.4 90/08/09 03:50:22 lwall Locked $ |
a687059c |
2 | * |
3 | * Copyright (c) 1989, Larry Wall |
4 | * |
5 | * You may distribute under the terms of the GNU General Public License |
6 | * as specified in the README file that comes with the perl 3.0 kit. |
8d063cd8 |
7 | * |
8 | * $Log: hash.c,v $ |
154e51a4 |
9 | * Revision 3.0.1.4 90/08/09 03:50:22 lwall |
10 | * patch19: dbmopen(name, 'filename', undef) now refrains from creating |
11 | * |
b1248f16 |
12 | * Revision 3.0.1.3 90/03/27 15:59:09 lwall |
13 | * patch16: @dbmvalues{'foo','bar'} could use the same cache entry for both values |
14 | * |
663a0e37 |
15 | * Revision 3.0.1.2 89/12/21 20:03:39 lwall |
16 | * patch7: errno may now be a macro with an lvalue |
17 | * |
bf38876a |
18 | * Revision 3.0.1.1 89/11/11 04:34:18 lwall |
19 | * patch2: CX/UX needed to set the key each time in associative iterators |
20 | * |
a687059c |
21 | * Revision 3.0 89/10/18 15:18:32 lwall |
22 | * 3.0 baseline |
8d063cd8 |
23 | * |
24 | */ |
25 | |
8d063cd8 |
26 | #include "EXTERN.h" |
8d063cd8 |
27 | #include "perl.h" |
28 | |
154e51a4 |
29 | static char coeff[] = { |
30 | 61,59,53,47,43,41,37,31,29,23,17,13,11,7,3,1, |
31 | 61,59,53,47,43,41,37,31,29,23,17,13,11,7,3,1, |
32 | 61,59,53,47,43,41,37,31,29,23,17,13,11,7,3,1, |
33 | 61,59,53,47,43,41,37,31,29,23,17,13,11,7,3,1, |
34 | 61,59,53,47,43,41,37,31,29,23,17,13,11,7,3,1, |
35 | 61,59,53,47,43,41,37,31,29,23,17,13,11,7,3,1, |
36 | 61,59,53,47,43,41,37,31,29,23,17,13,11,7,3,1, |
37 | 61,59,53,47,43,41,37,31,29,23,17,13,11,7,3,1}; |
38 | |
8d063cd8 |
39 | STR * |
a687059c |
40 | hfetch(tb,key,klen,lval) |
8d063cd8 |
41 | register HASH *tb; |
42 | char *key; |
a687059c |
43 | int klen; |
44 | int lval; |
8d063cd8 |
45 | { |
46 | register char *s; |
47 | register int i; |
48 | register int hash; |
49 | register HENT *entry; |
a687059c |
50 | register int maxi; |
51 | STR *str; |
52 | #ifdef SOME_DBM |
53 | datum dkey,dcontent; |
54 | #endif |
8d063cd8 |
55 | |
56 | if (!tb) |
57 | return Nullstr; |
a687059c |
58 | |
59 | /* The hash function we use on symbols has to be equal to the first |
60 | * character when taken modulo 128, so that str_reset() can be implemented |
61 | * efficiently. We throw in the second character and the last character |
62 | * (times 128) so that long chains of identifiers starting with the |
63 | * same letter don't have to be strEQ'ed within hfetch(), since it |
64 | * compares hash values before trying strEQ(). |
65 | */ |
66 | if (!tb->tbl_coeffsize) |
67 | hash = *key + 128 * key[1] + 128 * key[klen-1]; /* assuming klen > 0 */ |
68 | else { /* use normal coefficients */ |
69 | if (klen < tb->tbl_coeffsize) |
70 | maxi = klen; |
71 | else |
72 | maxi = tb->tbl_coeffsize; |
73 | for (s=key, i=0, hash = 0; |
74 | i < maxi; |
75 | s++, i++, hash *= 5) { |
76 | hash += *s * coeff[i]; |
77 | } |
8d063cd8 |
78 | } |
a687059c |
79 | |
8d063cd8 |
80 | entry = tb->tbl_array[hash & tb->tbl_max]; |
81 | for (; entry; entry = entry->hent_next) { |
82 | if (entry->hent_hash != hash) /* strings can't be equal */ |
83 | continue; |
a687059c |
84 | if (entry->hent_klen != klen) |
85 | continue; |
86 | if (bcmp(entry->hent_key,key,klen)) /* is this it? */ |
8d063cd8 |
87 | continue; |
88 | return entry->hent_val; |
89 | } |
a687059c |
90 | #ifdef SOME_DBM |
91 | if (tb->tbl_dbm) { |
92 | dkey.dptr = key; |
93 | dkey.dsize = klen; |
94 | dcontent = dbm_fetch(tb->tbl_dbm,dkey); |
95 | if (dcontent.dptr) { /* found one */ |
96 | str = Str_new(60,dcontent.dsize); |
97 | str_nset(str,dcontent.dptr,dcontent.dsize); |
98 | hstore(tb,key,klen,str,hash); /* cache it */ |
99 | return str; |
100 | } |
101 | } |
102 | #endif |
103 | if (lval) { /* gonna assign to this, so it better be there */ |
104 | str = Str_new(61,0); |
105 | hstore(tb,key,klen,str,hash); |
106 | return str; |
107 | } |
8d063cd8 |
108 | return Nullstr; |
109 | } |
110 | |
111 | bool |
a687059c |
112 | hstore(tb,key,klen,val,hash) |
8d063cd8 |
113 | register HASH *tb; |
114 | char *key; |
a687059c |
115 | int klen; |
8d063cd8 |
116 | STR *val; |
a687059c |
117 | register int hash; |
8d063cd8 |
118 | { |
119 | register char *s; |
120 | register int i; |
8d063cd8 |
121 | register HENT *entry; |
122 | register HENT **oentry; |
a687059c |
123 | register int maxi; |
8d063cd8 |
124 | |
125 | if (!tb) |
126 | return FALSE; |
a687059c |
127 | |
128 | if (hash) |
129 | ; |
130 | else if (!tb->tbl_coeffsize) |
131 | hash = *key + 128 * key[1] + 128 * key[klen-1]; |
132 | else { /* use normal coefficients */ |
133 | if (klen < tb->tbl_coeffsize) |
134 | maxi = klen; |
135 | else |
136 | maxi = tb->tbl_coeffsize; |
137 | for (s=key, i=0, hash = 0; |
138 | i < maxi; |
139 | s++, i++, hash *= 5) { |
140 | hash += *s * coeff[i]; |
141 | } |
8d063cd8 |
142 | } |
143 | |
144 | oentry = &(tb->tbl_array[hash & tb->tbl_max]); |
145 | i = 1; |
146 | |
147 | for (entry = *oentry; entry; i=0, entry = entry->hent_next) { |
148 | if (entry->hent_hash != hash) /* strings can't be equal */ |
149 | continue; |
a687059c |
150 | if (entry->hent_klen != klen) |
151 | continue; |
152 | if (bcmp(entry->hent_key,key,klen)) /* is this it? */ |
8d063cd8 |
153 | continue; |
a687059c |
154 | Safefree(entry->hent_val); |
8d063cd8 |
155 | entry->hent_val = val; |
156 | return TRUE; |
157 | } |
a687059c |
158 | New(501,entry, 1, HENT); |
8d063cd8 |
159 | |
a687059c |
160 | entry->hent_klen = klen; |
161 | entry->hent_key = nsavestr(key,klen); |
8d063cd8 |
162 | entry->hent_val = val; |
163 | entry->hent_hash = hash; |
164 | entry->hent_next = *oentry; |
165 | *oentry = entry; |
166 | |
a687059c |
167 | /* hdbmstore not necessary here because it's called from stabset() */ |
168 | |
8d063cd8 |
169 | if (i) { /* initial entry? */ |
170 | tb->tbl_fill++; |
a687059c |
171 | #ifdef SOME_DBM |
172 | if (tb->tbl_dbm && tb->tbl_max >= DBM_CACHE_MAX) |
173 | return FALSE; |
174 | #endif |
175 | if (tb->tbl_fill > tb->tbl_dosplit) |
8d063cd8 |
176 | hsplit(tb); |
177 | } |
a687059c |
178 | #ifdef SOME_DBM |
179 | else if (tb->tbl_dbm) { /* is this just a cache for dbm file? */ |
b1248f16 |
180 | void hentdelayfree(); |
181 | |
a687059c |
182 | entry = tb->tbl_array[hash & tb->tbl_max]; |
183 | oentry = &entry->hent_next; |
184 | entry = *oentry; |
185 | while (entry) { /* trim chain down to 1 entry */ |
186 | *oentry = entry->hent_next; |
b1248f16 |
187 | hentdelayfree(entry); /* no doubt they'll want this next. */ |
a687059c |
188 | entry = *oentry; |
189 | } |
190 | } |
191 | #endif |
8d063cd8 |
192 | |
193 | return FALSE; |
194 | } |
195 | |
378cc40b |
196 | STR * |
a687059c |
197 | hdelete(tb,key,klen) |
8d063cd8 |
198 | register HASH *tb; |
199 | char *key; |
a687059c |
200 | int klen; |
8d063cd8 |
201 | { |
202 | register char *s; |
203 | register int i; |
204 | register int hash; |
205 | register HENT *entry; |
206 | register HENT **oentry; |
378cc40b |
207 | STR *str; |
a687059c |
208 | int maxi; |
209 | #ifdef SOME_DBM |
210 | datum dkey; |
211 | #endif |
8d063cd8 |
212 | |
213 | if (!tb) |
378cc40b |
214 | return Nullstr; |
a687059c |
215 | if (!tb->tbl_coeffsize) |
216 | hash = *key + 128 * key[1] + 128 * key[klen-1]; |
217 | else { /* use normal coefficients */ |
218 | if (klen < tb->tbl_coeffsize) |
219 | maxi = klen; |
220 | else |
221 | maxi = tb->tbl_coeffsize; |
222 | for (s=key, i=0, hash = 0; |
223 | i < maxi; |
224 | s++, i++, hash *= 5) { |
225 | hash += *s * coeff[i]; |
226 | } |
8d063cd8 |
227 | } |
228 | |
229 | oentry = &(tb->tbl_array[hash & tb->tbl_max]); |
230 | entry = *oentry; |
231 | i = 1; |
378cc40b |
232 | for (; entry; i=0, oentry = &entry->hent_next, entry = *oentry) { |
8d063cd8 |
233 | if (entry->hent_hash != hash) /* strings can't be equal */ |
234 | continue; |
a687059c |
235 | if (entry->hent_klen != klen) |
236 | continue; |
237 | if (bcmp(entry->hent_key,key,klen)) /* is this it? */ |
8d063cd8 |
238 | continue; |
8d063cd8 |
239 | *oentry = entry->hent_next; |
378cc40b |
240 | str = str_static(entry->hent_val); |
241 | hentfree(entry); |
8d063cd8 |
242 | if (i) |
243 | tb->tbl_fill--; |
a687059c |
244 | #ifdef SOME_DBM |
245 | do_dbm_delete: |
246 | if (tb->tbl_dbm) { |
247 | dkey.dptr = key; |
248 | dkey.dsize = klen; |
249 | dbm_delete(tb->tbl_dbm,dkey); |
250 | } |
251 | #endif |
378cc40b |
252 | return str; |
8d063cd8 |
253 | } |
a687059c |
254 | #ifdef SOME_DBM |
255 | str = Nullstr; |
256 | goto do_dbm_delete; |
257 | #else |
378cc40b |
258 | return Nullstr; |
a687059c |
259 | #endif |
8d063cd8 |
260 | } |
8d063cd8 |
261 | |
262 | hsplit(tb) |
263 | HASH *tb; |
264 | { |
265 | int oldsize = tb->tbl_max + 1; |
266 | register int newsize = oldsize * 2; |
267 | register int i; |
268 | register HENT **a; |
269 | register HENT **b; |
270 | register HENT *entry; |
271 | register HENT **oentry; |
272 | |
a687059c |
273 | a = tb->tbl_array; |
274 | Renew(a, newsize, HENT*); |
275 | Zero(&a[oldsize], oldsize, HENT*); /* zero 2nd half*/ |
8d063cd8 |
276 | tb->tbl_max = --newsize; |
a687059c |
277 | tb->tbl_dosplit = tb->tbl_max * FILLPCT / 100; |
8d063cd8 |
278 | tb->tbl_array = a; |
279 | |
280 | for (i=0; i<oldsize; i++,a++) { |
281 | if (!*a) /* non-existent */ |
282 | continue; |
283 | b = a+oldsize; |
284 | for (oentry = a, entry = *a; entry; entry = *oentry) { |
285 | if ((entry->hent_hash & newsize) != i) { |
286 | *oentry = entry->hent_next; |
287 | entry->hent_next = *b; |
288 | if (!*b) |
289 | tb->tbl_fill++; |
290 | *b = entry; |
291 | continue; |
292 | } |
293 | else |
294 | oentry = &entry->hent_next; |
295 | } |
296 | if (!*a) /* everything moved */ |
297 | tb->tbl_fill--; |
298 | } |
299 | } |
300 | |
301 | HASH * |
a687059c |
302 | hnew(lookat) |
303 | unsigned int lookat; |
8d063cd8 |
304 | { |
a687059c |
305 | register HASH *tb; |
8d063cd8 |
306 | |
a687059c |
307 | Newz(502,tb, 1, HASH); |
308 | if (lookat) { |
309 | tb->tbl_coeffsize = lookat; |
310 | tb->tbl_max = 7; /* it's a normal associative array */ |
311 | tb->tbl_dosplit = tb->tbl_max * FILLPCT / 100; |
312 | } |
313 | else { |
314 | tb->tbl_max = 127; /* it's a symbol table */ |
315 | tb->tbl_dosplit = 128; /* so never split */ |
316 | } |
317 | Newz(503,tb->tbl_array, tb->tbl_max + 1, HENT*); |
8d063cd8 |
318 | tb->tbl_fill = 0; |
a687059c |
319 | #ifdef SOME_DBM |
320 | tb->tbl_dbm = 0; |
321 | #endif |
322 | (void)hiterinit(tb); /* so each() will start off right */ |
8d063cd8 |
323 | return tb; |
324 | } |
325 | |
378cc40b |
326 | void |
327 | hentfree(hent) |
328 | register HENT *hent; |
329 | { |
330 | if (!hent) |
331 | return; |
332 | str_free(hent->hent_val); |
a687059c |
333 | Safefree(hent->hent_key); |
334 | Safefree(hent); |
378cc40b |
335 | } |
336 | |
337 | void |
b1248f16 |
338 | hentdelayfree(hent) |
339 | register HENT *hent; |
340 | { |
341 | if (!hent) |
342 | return; |
343 | str_2static(hent->hent_val); /* free between statements */ |
344 | Safefree(hent->hent_key); |
345 | Safefree(hent); |
346 | } |
347 | |
348 | void |
378cc40b |
349 | hclear(tb) |
350 | register HASH *tb; |
351 | { |
352 | register HENT *hent; |
353 | register HENT *ohent = Null(HENT*); |
354 | |
355 | if (!tb) |
356 | return; |
a687059c |
357 | (void)hiterinit(tb); |
378cc40b |
358 | while (hent = hiternext(tb)) { /* concise but not very efficient */ |
359 | hentfree(ohent); |
360 | ohent = hent; |
361 | } |
362 | hentfree(ohent); |
363 | tb->tbl_fill = 0; |
a687059c |
364 | #ifndef lint |
365 | (void)bzero((char*)tb->tbl_array, (tb->tbl_max + 1) * sizeof(HENT*)); |
366 | #endif |
378cc40b |
367 | } |
368 | |
378cc40b |
369 | void |
370 | hfree(tb) |
a687059c |
371 | register HASH *tb; |
378cc40b |
372 | { |
a687059c |
373 | register HENT *hent; |
374 | register HENT *ohent = Null(HENT*); |
375 | |
378cc40b |
376 | if (!tb) |
a687059c |
377 | return; |
378 | (void)hiterinit(tb); |
378cc40b |
379 | while (hent = hiternext(tb)) { |
380 | hentfree(ohent); |
381 | ohent = hent; |
382 | } |
383 | hentfree(ohent); |
a687059c |
384 | Safefree(tb->tbl_array); |
385 | Safefree(tb); |
378cc40b |
386 | } |
8d063cd8 |
387 | |
a687059c |
388 | int |
8d063cd8 |
389 | hiterinit(tb) |
390 | register HASH *tb; |
391 | { |
392 | tb->tbl_riter = -1; |
393 | tb->tbl_eiter = Null(HENT*); |
394 | return tb->tbl_fill; |
395 | } |
396 | |
397 | HENT * |
398 | hiternext(tb) |
399 | register HASH *tb; |
400 | { |
401 | register HENT *entry; |
a687059c |
402 | #ifdef SOME_DBM |
403 | datum key; |
404 | #endif |
8d063cd8 |
405 | |
406 | entry = tb->tbl_eiter; |
a687059c |
407 | #ifdef SOME_DBM |
408 | if (tb->tbl_dbm) { |
409 | if (entry) { |
410 | #ifdef NDBM |
411 | #ifdef _CX_UX |
bf38876a |
412 | key.dptr = entry->hent_key; |
413 | key.dsize = entry->hent_klen; |
a687059c |
414 | key = dbm_nextkey(tb->tbl_dbm, key); |
415 | #else |
416 | key = dbm_nextkey(tb->tbl_dbm); |
417 | #endif /* _CX_UX */ |
418 | #else |
419 | key.dptr = entry->hent_key; |
420 | key.dsize = entry->hent_klen; |
421 | key = nextkey(key); |
422 | #endif |
423 | } |
424 | else { |
425 | Newz(504,entry, 1, HENT); |
426 | tb->tbl_eiter = entry; |
427 | key = dbm_firstkey(tb->tbl_dbm); |
428 | } |
429 | entry->hent_key = key.dptr; |
430 | entry->hent_klen = key.dsize; |
431 | if (!key.dptr) { |
432 | if (entry->hent_val) |
433 | str_free(entry->hent_val); |
434 | Safefree(entry); |
435 | tb->tbl_eiter = Null(HENT*); |
436 | return Null(HENT*); |
437 | } |
438 | return entry; |
439 | } |
440 | #endif |
8d063cd8 |
441 | do { |
442 | if (entry) |
443 | entry = entry->hent_next; |
444 | if (!entry) { |
445 | tb->tbl_riter++; |
446 | if (tb->tbl_riter > tb->tbl_max) { |
447 | tb->tbl_riter = -1; |
448 | break; |
449 | } |
450 | entry = tb->tbl_array[tb->tbl_riter]; |
451 | } |
452 | } while (!entry); |
453 | |
454 | tb->tbl_eiter = entry; |
455 | return entry; |
456 | } |
457 | |
458 | char * |
a687059c |
459 | hiterkey(entry,retlen) |
8d063cd8 |
460 | register HENT *entry; |
a687059c |
461 | int *retlen; |
8d063cd8 |
462 | { |
a687059c |
463 | *retlen = entry->hent_klen; |
8d063cd8 |
464 | return entry->hent_key; |
465 | } |
466 | |
467 | STR * |
a687059c |
468 | hiterval(tb,entry) |
469 | register HASH *tb; |
8d063cd8 |
470 | register HENT *entry; |
471 | { |
a687059c |
472 | #ifdef SOME_DBM |
473 | datum key, content; |
474 | |
475 | if (tb->tbl_dbm) { |
476 | key.dptr = entry->hent_key; |
477 | key.dsize = entry->hent_klen; |
478 | content = dbm_fetch(tb->tbl_dbm,key); |
479 | if (!entry->hent_val) |
480 | entry->hent_val = Str_new(62,0); |
481 | str_nset(entry->hent_val,content.dptr,content.dsize); |
482 | } |
483 | #endif |
8d063cd8 |
484 | return entry->hent_val; |
485 | } |
a687059c |
486 | |
487 | #ifdef SOME_DBM |
488 | #if defined(FCNTL) && ! defined(O_CREAT) |
489 | #include <fcntl.h> |
490 | #endif |
491 | |
492 | #ifndef O_RDONLY |
493 | #define O_RDONLY 0 |
494 | #endif |
495 | #ifndef O_RDWR |
496 | #define O_RDWR 2 |
497 | #endif |
498 | #ifndef O_CREAT |
499 | #define O_CREAT 01000 |
500 | #endif |
501 | |
502 | #ifndef NDBM |
503 | static int dbmrefcnt = 0; |
504 | #endif |
505 | |
506 | bool |
507 | hdbmopen(tb,fname,mode) |
508 | register HASH *tb; |
509 | char *fname; |
510 | int mode; |
511 | { |
512 | if (!tb) |
513 | return FALSE; |
514 | #ifndef NDBM |
515 | if (tb->tbl_dbm) /* never really closed it */ |
516 | return TRUE; |
517 | #endif |
154e51a4 |
518 | if (tb->tbl_dbm) { |
a687059c |
519 | hdbmclose(tb); |
154e51a4 |
520 | tb->tbl_dbm = 0; |
521 | } |
a687059c |
522 | hclear(tb); |
523 | #ifdef NDBM |
154e51a4 |
524 | if (mode >= 0) |
525 | tb->tbl_dbm = dbm_open(fname, O_RDWR|O_CREAT, mode); |
526 | if (!tb->tbl_dbm) |
527 | tb->tbl_dbm = dbm_open(fname, O_RDWR, mode); |
a687059c |
528 | #else |
529 | if (dbmrefcnt++) |
530 | fatal("Old dbm can only open one database"); |
531 | sprintf(buf,"%s.dir",fname); |
532 | if (stat(buf, &statbuf) < 0) { |
154e51a4 |
533 | if (mode < 0 || close(creat(buf,mode)) < 0) |
a687059c |
534 | return FALSE; |
535 | sprintf(buf,"%s.pag",fname); |
536 | if (close(creat(buf,mode)) < 0) |
537 | return FALSE; |
538 | } |
539 | tb->tbl_dbm = dbminit(fname) >= 0; |
540 | #endif |
541 | return tb->tbl_dbm != 0; |
542 | } |
543 | |
544 | void |
545 | hdbmclose(tb) |
546 | register HASH *tb; |
547 | { |
548 | if (tb && tb->tbl_dbm) { |
549 | #ifdef NDBM |
550 | dbm_close(tb->tbl_dbm); |
551 | tb->tbl_dbm = 0; |
552 | #else |
553 | /* dbmrefcnt--; */ /* doesn't work, rats */ |
554 | #endif |
555 | } |
556 | else if (dowarn) |
557 | warn("Close on unopened dbm file"); |
558 | } |
559 | |
560 | bool |
561 | hdbmstore(tb,key,klen,str) |
562 | register HASH *tb; |
563 | char *key; |
564 | int klen; |
565 | register STR *str; |
566 | { |
567 | datum dkey, dcontent; |
568 | int error; |
569 | |
570 | if (!tb || !tb->tbl_dbm) |
571 | return FALSE; |
572 | dkey.dptr = key; |
573 | dkey.dsize = klen; |
574 | dcontent.dptr = str_get(str); |
575 | dcontent.dsize = str->str_cur; |
576 | error = dbm_store(tb->tbl_dbm, dkey, dcontent, DBM_REPLACE); |
577 | if (error) { |
578 | if (errno == EPERM) |
579 | fatal("No write permission to dbm file"); |
580 | warn("dbm store returned %d, errno %d, key \"%s\"",error,errno,key); |
581 | #ifdef NDBM |
582 | dbm_clearerr(tb->tbl_dbm); |
583 | #endif |
584 | } |
585 | return !error; |
586 | } |
587 | #endif /* SOME_DBM */ |