Asterisk - The Open Source Telephony Project GIT-master-55f4e6d
hash.c
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1/*-
2 * Copyright (c) 1990, 1993, 1994
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Margo Seltzer.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37#if defined(LIBC_SCCS) && !defined(lint)
38static char sccsid[] = "@(#)hash.c 8.9 (Berkeley) 6/16/94";
39#endif /* LIBC_SCCS and not lint */
40
41#include <sys/param.h>
42#include <sys/stat.h>
43
44#include <errno.h>
45#include <fcntl.h>
46#include <stdio.h>
47#include <stdlib.h>
48#include <string.h>
49#include <unistd.h>
50#ifdef DEBUG
51#include <assert.h>
52#endif
53
54#include "../include/db.h"
55#include "hash.h"
56#include "page.h"
57#include "extern.h"
58
59static int alloc_segs __P((HTAB *, int));
60static int flush_meta __P((HTAB *));
61static int hash_access __P((HTAB *, ACTION, DBT *, DBT *));
62static int hash_close __P((DB *));
63static int hash_delete __P((const DB *, const DBT *, u_int32_t));
64static int hash_fd __P((const DB *));
65static int hash_get __P((const DB *, const DBT *, DBT *, u_int32_t));
66static int hash_put __P((const DB *, DBT *, const DBT *, u_int32_t));
67static void *hash_realloc __P((SEGMENT **, int, int));
68static int hash_seq __P((const DB *, DBT *, DBT *, u_int32_t));
69static int hash_sync __P((const DB *, u_int32_t));
70static int hdestroy __P((HTAB *));
71static HTAB *init_hash __P((HTAB *, const char *, const HASHINFO *));
72static int init_htab __P((HTAB *, int));
73#if BYTE_ORDER == LITTLE_ENDIAN
74static void swap_header __P((HTAB *));
75static void swap_header_copy __P((HASHHDR *, HASHHDR *));
76#endif
77
78/* Fast arithmetic, relying on powers of 2, */
79#define MOD(x, y) ((x) & ((y) - 1))
80
81#define RETURN_ERROR(ERR, LOC) { save_errno = ERR; goto LOC; }
82
83/* Return values */
84#define SUCCESS (0)
85#define ERROR (-1)
86#define ABNORMAL (1)
87
88#ifdef HASH_STATISTICS
89int hash_accesses, hash_collisions, hash_expansions, hash_overflows;
90#endif
91
92/************************** INTERFACE ROUTINES ***************************/
93/* OPEN/CLOSE */
94
95extern DB *
96__hash_open(file, flags, mode, info, dflags)
97 const char *file;
98 int flags, mode, dflags;
99 const HASHINFO *info; /* Special directives for create */
100{
101 HTAB *hashp;
102 struct stat statbuf;
103 DB *dbp;
104 int bpages, hdrsize, new_table, nsegs, save_errno;
105
106 if ((flags & O_ACCMODE) == O_WRONLY) {
107 errno = EINVAL;
108 return (NULL);
109 }
110
111 if (!(hashp = (HTAB *)calloc(1, sizeof(HTAB))))
112 return (NULL);
113 hashp->fp = -1;
114
115 /*
116 * Even if user wants write only, we need to be able to read
117 * the actual file, so we need to open it read/write. But, the
118 * field in the hashp structure needs to be accurate so that
119 * we can check accesses.
120 */
121 hashp->flags = flags;
122
123 new_table = 0;
124 if (!file || (flags & O_TRUNC) ||
125 (stat(file, &statbuf) && (errno == ENOENT))) {
126 if (errno == ENOENT)
127 errno = 0; /* Just in case someone looks at errno */
128 new_table = 1;
129 }
130 if (file) {
131 if ((hashp->fp = open(file, flags, mode)) == -1)
132 RETURN_ERROR(errno, error0);
133 (void)fcntl(hashp->fp, F_SETFD, 1);
134 }
135 if (new_table) {
136 if (!(hashp = init_hash(hashp, file, info)))
137 RETURN_ERROR(errno, error1);
138 } else {
139 /* Table already exists */
140 if (info && info->hash)
141 hashp->hash = info->hash;
142 else
143 hashp->hash = __default_hash;
144
145 hdrsize = read(hashp->fp, &hashp->hdr, sizeof(HASHHDR));
146#if BYTE_ORDER == LITTLE_ENDIAN
147 swap_header(hashp);
148#endif
149 if (hdrsize == -1)
150 RETURN_ERROR(errno, error1);
151 if (hdrsize != sizeof(HASHHDR))
152 RETURN_ERROR(EFTYPE, error1);
153 /* Verify file type, versions and hash function */
154 if (hashp->MAGIC != HASHMAGIC)
155 RETURN_ERROR(EFTYPE, error1);
156#define OLDHASHVERSION 1
157 if (hashp->VERSION != HASHVERSION &&
158 hashp->VERSION != OLDHASHVERSION)
159 RETURN_ERROR(EFTYPE, error1);
160 if (hashp->hash(CHARKEY, sizeof(CHARKEY))
161 != (u_int32_t) hashp->H_CHARKEY)
162 RETURN_ERROR(EFTYPE, error1);
163 /*
164 * Figure out how many segments we need. Max_Bucket is the
165 * maximum bucket number, so the number of buckets is
166 * max_bucket + 1.
167 */
168 nsegs = (hashp->MAX_BUCKET + 1 + hashp->SGSIZE - 1) /
169 hashp->SGSIZE;
170 hashp->nsegs = 0;
171 if (alloc_segs(hashp, nsegs))
172 /*
173 * If alloc_segs fails, table will have been destroyed
174 * and errno will have been set.
175 */
176 return (NULL);
177 /* Read in bitmaps */
178 bpages = (hashp->SPARES[hashp->OVFL_POINT] +
179 (hashp->BSIZE << BYTE_SHIFT) - 1) >>
180 (hashp->BSHIFT + BYTE_SHIFT);
181
182 hashp->nmaps = bpages;
183 (void)memset(&hashp->mapp[0], 0, bpages * sizeof(u_int32_t *));
184 }
185
186 /* Initialize Buffer Manager */
187 if (info && info->cachesize)
188 __buf_init(hashp, info->cachesize);
189 else
190 __buf_init(hashp, DEF_BUFSIZE);
191
192 hashp->new_file = new_table;
193 hashp->save_file = file && (hashp->flags & O_ACCMODE) != O_RDONLY;
194 hashp->cbucket = -1;
195 if (!(dbp = (DB *)malloc(sizeof(DB)))) {
196 save_errno = errno;
197 hdestroy(hashp);
198 errno = save_errno;
199 return (NULL);
200 }
201 dbp->internal = hashp;
202 dbp->close = hash_close;
203 dbp->del = hash_delete;
204 dbp->fd = hash_fd;
205 dbp->get = hash_get;
206 dbp->put = hash_put;
207 dbp->seq = hash_seq;
208 dbp->sync = hash_sync;
209 dbp->type = DB_HASH;
210
211#ifdef DEBUG
212 (void)fprintf(stderr,
213"%s\n%s%x\n%s%d\n%s%d\n%s%d\n%s%d\n%s%d\n%s%d\n%s%d\n%s%d\n%s%d\n%s%x\n%s%x\n%s%d\n%s%d\n",
214 "init_htab:",
215 "TABLE POINTER ", hashp,
216 "BUCKET SIZE ", hashp->BSIZE,
217 "BUCKET SHIFT ", hashp->BSHIFT,
218 "DIRECTORY SIZE ", hashp->DSIZE,
219 "SEGMENT SIZE ", hashp->SGSIZE,
220 "SEGMENT SHIFT ", hashp->SSHIFT,
221 "FILL FACTOR ", hashp->FFACTOR,
222 "MAX BUCKET ", hashp->MAX_BUCKET,
223 "OVFL POINT ", hashp->OVFL_POINT,
224 "LAST FREED ", hashp->LAST_FREED,
225 "HIGH MASK ", hashp->HIGH_MASK,
226 "LOW MASK ", hashp->LOW_MASK,
227 "NSEGS ", hashp->nsegs,
228 "NKEYS ", hashp->NKEYS);
229#endif
230#ifdef HASH_STATISTICS
231 hash_overflows = hash_accesses = hash_collisions = hash_expansions = 0;
232#endif
233 return (dbp);
234
235error1:
236 if (hashp != NULL)
237 (void)close(hashp->fp);
238
239error0:
240 free(hashp);
241 errno = save_errno;
242 return (NULL);
243}
244
245static int
247 DB *dbp;
248{
249 HTAB *hashp;
250 int retval;
251
252 if (!dbp)
253 return (ERROR);
254
255 hashp = (HTAB *)dbp->internal;
256 retval = hdestroy(hashp);
257 free(dbp);
258 return (retval);
259}
260
261static int
263 const DB *dbp;
264{
265 HTAB *hashp;
266
267 if (!dbp)
268 return (ERROR);
269
270 hashp = (HTAB *)dbp->internal;
271 if (hashp->fp == -1) {
272 errno = ENOENT;
273 return (-1);
274 }
275 return (hashp->fp);
276}
277
278/************************** LOCAL CREATION ROUTINES **********************/
279static HTAB *
281 HTAB *hashp;
282 const char *file;
283 const HASHINFO *info;
284{
285#ifdef _STATBUF_ST_BLKSIZE
286 struct stat statbuf;
287#endif
288 int nelem;
289
290 nelem = 1;
291 hashp->NKEYS = 0;
292 hashp->LORDER = BYTE_ORDER;
293 hashp->BSIZE = DEF_BUCKET_SIZE;
294 hashp->BSHIFT = DEF_BUCKET_SHIFT;
295 hashp->SGSIZE = DEF_SEGSIZE;
296 hashp->SSHIFT = DEF_SEGSIZE_SHIFT;
297 hashp->DSIZE = DEF_DIRSIZE;
298 hashp->FFACTOR = DEF_FFACTOR;
299 hashp->hash = __default_hash;
300 memset(hashp->SPARES, 0, sizeof(hashp->SPARES));
301 memset(hashp->BITMAPS, 0, sizeof (hashp->BITMAPS));
302
303 /* Fix bucket size to be optimal for file system */
304#ifdef _STATBUF_ST_BLKSIZE
305 if (file != NULL) {
306 if (stat(file, &statbuf))
307 return (NULL);
308 hashp->BSIZE = statbuf.st_blksize;
309 hashp->BSHIFT = __hash_log2(hashp->BSIZE);
310 }
311#endif
312
313 if (info) {
314 if (info->bsize) {
315 /* Round pagesize up to power of 2 */
316 hashp->BSHIFT = __hash_log2(info->bsize);
317 hashp->BSIZE = 1 << hashp->BSHIFT;
318 if (hashp->BSIZE > MAX_BSIZE) {
319 errno = EINVAL;
320 return (NULL);
321 }
322 }
323 if (info->ffactor)
324 hashp->FFACTOR = info->ffactor;
325 if (info->hash)
326 hashp->hash = info->hash;
327 if (info->nelem)
328 nelem = info->nelem;
329 if (info->lorder) {
330 if (info->lorder != BIG_ENDIAN &&
331 info->lorder != LITTLE_ENDIAN) {
332 errno = EINVAL;
333 return (NULL);
334 }
335 hashp->LORDER = info->lorder;
336 }
337 }
338 /* init_htab should destroy the table and set errno if it fails */
339 if (init_htab(hashp, nelem))
340 return (NULL);
341 else
342 return (hashp);
343}
344/*
345 * This calls alloc_segs which may run out of memory. Alloc_segs will destroy
346 * the table and set errno, so we just pass the error information along.
347 *
348 * Returns 0 on No Error
349 */
350static int
351init_htab(hashp, nelem)
352 HTAB *hashp;
353 int nelem;
354{
355 register int nbuckets, nsegs;
356 int l2;
357
358 /*
359 * Divide number of elements by the fill factor and determine a
360 * desired number of buckets. Allocate space for the next greater
361 * power of two number of buckets.
362 */
363 nelem = (nelem - 1) / hashp->FFACTOR + 1;
364
365 l2 = __hash_log2(MAX(nelem, 2));
366 nbuckets = 1 << l2;
367
368 hashp->SPARES[l2] = l2 + 1;
369 hashp->SPARES[l2 + 1] = l2 + 1;
370 hashp->OVFL_POINT = l2;
371 hashp->LAST_FREED = 2;
372
373 /* First bitmap page is at: splitpoint l2 page offset 1 */
374 if (__ibitmap(hashp, OADDR_OF(l2, 1), l2 + 1, 0))
375 return (-1);
376
377 hashp->MAX_BUCKET = hashp->LOW_MASK = nbuckets - 1;
378 hashp->HIGH_MASK = (nbuckets << 1) - 1;
379 hashp->HDRPAGES = ((MAX(sizeof(HASHHDR), MINHDRSIZE) - 1) >>
380 hashp->BSHIFT) + 1;
381
382 nsegs = (nbuckets - 1) / hashp->SGSIZE + 1;
383 nsegs = 1 << __hash_log2(nsegs);
384
385 if (nsegs > hashp->DSIZE)
386 hashp->DSIZE = nsegs;
387 return (alloc_segs(hashp, nsegs));
388}
389
390/********************** DESTROY/CLOSE ROUTINES ************************/
391
392/*
393 * Flushes any changes to the file if necessary and destroys the hashp
394 * structure, freeing all allocated space.
395 */
396static int
398 HTAB *hashp;
399{
400 int i, save_errno;
401
402 save_errno = 0;
403
404#ifdef HASH_STATISTICS
405 (void)fprintf(stderr, "hdestroy: accesses %ld collisions %ld\n",
406 hash_accesses, hash_collisions);
407 (void)fprintf(stderr, "hdestroy: expansions %ld\n",
408 hash_expansions);
409 (void)fprintf(stderr, "hdestroy: overflows %ld\n",
410 hash_overflows);
411 (void)fprintf(stderr, "keys %ld maxp %d segmentcount %d\n",
412 hashp->NKEYS, hashp->MAX_BUCKET, hashp->nsegs);
413
414 for (i = 0; i < NCACHED; i++)
415 (void)fprintf(stderr,
416 "spares[%d] = %d\n", i, hashp->SPARES[i]);
417#endif
418 /*
419 * Call on buffer manager to free buffers, and if required,
420 * write them to disk.
421 */
422 if (__buf_free(hashp, 1, hashp->save_file))
423 save_errno = errno;
424 if (hashp->dir) {
425 free(*hashp->dir); /* Free initial segments */
426 /* Free extra segments */
427 while (hashp->exsegs--)
428 free(hashp->dir[--hashp->nsegs]);
429 free(hashp->dir);
430 }
431 if (flush_meta(hashp) && !save_errno)
432 save_errno = errno;
433 /* Free Bigmaps */
434 for (i = 0; i < hashp->nmaps; i++)
435 if (hashp->mapp[i])
436 free(hashp->mapp[i]);
437
438 if (hashp->fp != -1)
439 (void)close(hashp->fp);
440
441 free(hashp);
442
443 if (save_errno) {
444 errno = save_errno;
445 return (ERROR);
446 }
447 return (SUCCESS);
448}
449/*
450 * Write modified pages to disk
451 *
452 * Returns:
453 * 0 == OK
454 * -1 ERROR
455 */
456static int
458 const DB *dbp;
459 u_int32_t flags;
460{
461 HTAB *hashp;
462
463 if (flags != 0) {
464 errno = EINVAL;
465 return (ERROR);
466 }
467
468 if (!dbp)
469 return (ERROR);
470
471 hashp = (HTAB *)dbp->internal;
472 if (!hashp->save_file)
473 return (0);
474 if (__buf_free(hashp, 0, 1) || flush_meta(hashp))
475 return (ERROR);
476 hashp->new_file = 0;
477 return (0);
478}
479
480/*
481 * Returns:
482 * 0 == OK
483 * -1 indicates that errno should be set
484 */
485static int
487 HTAB *hashp;
488{
489 HASHHDR *whdrp;
490#if BYTE_ORDER == LITTLE_ENDIAN
491 HASHHDR whdr;
492#endif
493 int fp, i, wsize;
494
495 if (!hashp->save_file)
496 return (0);
497 hashp->MAGIC = HASHMAGIC;
498 hashp->VERSION = HASHVERSION;
499 hashp->H_CHARKEY = hashp->hash(CHARKEY, sizeof(CHARKEY));
500
501 fp = hashp->fp;
502 whdrp = &hashp->hdr;
503#if BYTE_ORDER == LITTLE_ENDIAN
504 whdrp = &whdr;
505 swap_header_copy(&hashp->hdr, whdrp);
506#endif
507 if ((lseek(fp, (off_t)0, SEEK_SET) == -1) ||
508 ((wsize = write(fp, whdrp, sizeof(HASHHDR))) == -1))
509 return (-1);
510 else
511 if (wsize != sizeof(HASHHDR)) {
512 errno = EFTYPE;
513 hashp->errnum = errno;
514 return (-1);
515 }
516 for (i = 0; i < NCACHED; i++)
517 if (hashp->mapp[i])
518 if (__put_page(hashp, (char *)hashp->mapp[i],
519 hashp->BITMAPS[i], 0, 1))
520 return (-1);
521 return (0);
522}
523
524/*******************************SEARCH ROUTINES *****************************/
525/*
526 * All the access routines return
527 *
528 * Returns:
529 * 0 on SUCCESS
530 * 1 to indicate an external ERROR (i.e. key not found, etc)
531 * -1 to indicate an internal ERROR (i.e. out of memory, etc)
532 */
533static int
534hash_get(dbp, key, data, flag)
535 const DB *dbp;
536 const DBT *key;
537 DBT *data;
539{
540 HTAB *hashp;
541
542 hashp = (HTAB *)dbp->internal;
543 if (flag) {
544 hashp->errnum = errno = EINVAL;
545 return (ERROR);
546 }
547 return (hash_access(hashp, HASH_GET, (DBT *)key, data));
548}
549
550static int
551hash_put(dbp, key, data, flag)
552 const DB *dbp;
553 DBT *key;
554 const DBT *data;
556{
557 HTAB *hashp;
558
559 hashp = (HTAB *)dbp->internal;
560 if (flag && flag != R_NOOVERWRITE) {
561 hashp->errnum = errno = EINVAL;
562 return (ERROR);
563 }
564 if ((hashp->flags & O_ACCMODE) == O_RDONLY) {
565 hashp->errnum = errno = EPERM;
566 return (ERROR);
567 }
568 return (hash_access(hashp, flag == R_NOOVERWRITE ?
569 HASH_PUTNEW : HASH_PUT, (DBT *)key, (DBT *)data));
570}
571
572static int
574 const DB *dbp;
575 const DBT *key;
576 u_int32_t flag; /* Ignored */
577{
578 HTAB *hashp;
579
580 hashp = (HTAB *)dbp->internal;
581 if (flag && flag != R_CURSOR) {
582 hashp->errnum = errno = EINVAL;
583 return (ERROR);
584 }
585 if ((hashp->flags & O_ACCMODE) == O_RDONLY) {
586 hashp->errnum = errno = EPERM;
587 return (ERROR);
588 }
589 return (hash_access(hashp, HASH_DELETE, (DBT *)key, NULL));
590}
591
592/*
593 * Assume that hashp has been set in wrapper routine.
594 */
595static int
596hash_access(hashp, action, key, val)
597 HTAB *hashp;
598 ACTION action;
599 DBT *key, *val;
600{
601 register BUFHEAD *rbufp;
602 BUFHEAD *bufp, *save_bufp;
603 register u_int16_t *bp;
604 register int n, ndx, off, size;
605 register char *kp;
606 u_int16_t pageno;
607
608#ifdef HASH_STATISTICS
609 hash_accesses++;
610#endif
611
612 off = hashp->BSIZE;
613 size = key->size;
614 kp = (char *)key->data;
615 rbufp = __get_buf(hashp, __call_hash(hashp, kp, size), NULL, 0);
616 if (!rbufp)
617 return (ERROR);
618 save_bufp = rbufp;
619
620 /* Pin the bucket chain */
621 rbufp->flags |= BUF_PIN;
622 for (bp = (u_int16_t *)rbufp->page, n = *bp++, ndx = 1; ndx < n;)
623 if (bp[1] >= REAL_KEY) {
624 /* Real key/data pair */
625 if (size == off - *bp &&
626 memcmp(kp, rbufp->page + *bp, size) == 0)
627 goto found;
628 off = bp[1];
629#ifdef HASH_STATISTICS
630 hash_collisions++;
631#endif
632 bp += 2;
633 ndx += 2;
634 } else if (bp[1] == OVFLPAGE) {
635 rbufp = __get_buf(hashp, *bp, rbufp, 0);
636 if (!rbufp) {
637 save_bufp->flags &= ~BUF_PIN;
638 return (ERROR);
639 }
640 /* FOR LOOP INIT */
641 bp = (u_int16_t *)rbufp->page;
642 n = *bp++;
643 ndx = 1;
644 off = hashp->BSIZE;
645 } else if (bp[1] < REAL_KEY) {
646 if ((ndx =
647 __find_bigpair(hashp, rbufp, ndx, kp, size)) > 0)
648 goto found;
649 if (ndx == -2) {
650 bufp = rbufp;
651 if (!(pageno =
652 __find_last_page(hashp, &bufp))) {
653 ndx = 0;
654 rbufp = bufp;
655 break; /* FOR */
656 }
657 rbufp = __get_buf(hashp, pageno, bufp, 0);
658 if (!rbufp) {
659 save_bufp->flags &= ~BUF_PIN;
660 return (ERROR);
661 }
662 /* FOR LOOP INIT */
663 bp = (u_int16_t *)rbufp->page;
664 n = *bp++;
665 ndx = 1;
666 off = hashp->BSIZE;
667 } else {
668 save_bufp->flags &= ~BUF_PIN;
669 return (ERROR);
670 }
671 }
672
673 /* Not found */
674 switch (action) {
675 case HASH_PUT:
676 case HASH_PUTNEW:
677 if (__addel(hashp, rbufp, key, val)) {
678 save_bufp->flags &= ~BUF_PIN;
679 return (ERROR);
680 } else {
681 save_bufp->flags &= ~BUF_PIN;
682 return (SUCCESS);
683 }
684 case HASH_GET:
685 case HASH_DELETE:
686 default:
687 save_bufp->flags &= ~BUF_PIN;
688 return (ABNORMAL);
689 }
690
691found:
692 switch (action) {
693 case HASH_PUTNEW:
694 save_bufp->flags &= ~BUF_PIN;
695 return (ABNORMAL);
696 case HASH_GET:
697 bp = (u_int16_t *)rbufp->page;
698 if (bp[ndx + 1] < REAL_KEY) {
699 if (__big_return(hashp, rbufp, ndx, val, 0))
700 return (ERROR);
701 } else {
702 val->data = (u_char *)rbufp->page + (int)bp[ndx + 1];
703 val->size = bp[ndx] - bp[ndx + 1];
704 }
705 break;
706 case HASH_PUT:
707 if ((__delpair(hashp, rbufp, ndx)) ||
708 (__addel(hashp, rbufp, key, val))) {
709 save_bufp->flags &= ~BUF_PIN;
710 return (ERROR);
711 }
712 break;
713 case HASH_DELETE:
714 if (__delpair(hashp, rbufp, ndx))
715 return (ERROR);
716 break;
717 default:
718 abort();
719 }
720 save_bufp->flags &= ~BUF_PIN;
721 return (SUCCESS);
722}
723
724static int
725hash_seq(dbp, key, data, flag)
726 const DB *dbp;
727 DBT *key, *data;
729{
730 register u_int32_t bucket;
731 register BUFHEAD *bufp = NULL;
732 HTAB *hashp;
733 u_int16_t *bp, ndx;
734
735 hashp = (HTAB *)dbp->internal;
736 if (flag && flag != R_FIRST && flag != R_NEXT) {
737 hashp->errnum = errno = EINVAL;
738 return (ERROR);
739 }
740#ifdef HASH_STATISTICS
741 hash_accesses++;
742#endif
743 if ((hashp->cbucket < 0) || (flag == R_FIRST)) {
744 hashp->cbucket = 0;
745 hashp->cndx = 1;
746 hashp->cpage = NULL;
747 }
748
749 for (bp = NULL; !bp || !bp[0]; ) {
750 if (!(bufp = hashp->cpage)) {
751 for (bucket = hashp->cbucket;
752 bucket <= (u_int32_t) hashp->MAX_BUCKET;
753 bucket++, hashp->cndx = 1) {
754 bufp = __get_buf(hashp, bucket, NULL, 0);
755 if (!bufp)
756 return (ERROR);
757 hashp->cpage = bufp;
758 bp = (u_int16_t *)bufp->page;
759 if (bp[0])
760 break;
761 }
762 hashp->cbucket = bucket;
763 if (hashp->cbucket > hashp->MAX_BUCKET) {
764 hashp->cbucket = -1;
765 return (ABNORMAL);
766 }
767 } else
768 bp = (u_int16_t *)hashp->cpage->page;
769
770#ifdef DEBUG
771 assert(bp);
772 assert(bufp);
773#endif
774 while (bp[hashp->cndx + 1] == OVFLPAGE) {
775 bufp = hashp->cpage =
776 __get_buf(hashp, bp[hashp->cndx], bufp, 0);
777 if (!bufp)
778 return (ERROR);
779 bp = (u_int16_t *)(bufp->page);
780 hashp->cndx = 1;
781 }
782 if (!bp[0]) {
783 hashp->cpage = NULL;
784 ++hashp->cbucket;
785 }
786 }
787 ndx = hashp->cndx;
788 if (bp[ndx + 1] < REAL_KEY) {
789 if (__big_keydata(hashp, bufp, key, data, 1))
790 return (ERROR);
791 } else {
792 key->data = (u_char *)hashp->cpage->page + bp[ndx];
793 key->size = (ndx > 1 ? bp[ndx - 1] : hashp->BSIZE) - bp[ndx];
794 data->data = (u_char *)hashp->cpage->page + bp[ndx + 1];
795 data->size = bp[ndx] - bp[ndx + 1];
796 ndx += 2;
797 if (ndx > bp[0]) {
798 hashp->cpage = NULL;
799 hashp->cbucket++;
800 hashp->cndx = 1;
801 } else
802 hashp->cndx = ndx;
803 }
804 return (SUCCESS);
805}
806
807/********************************* UTILITIES ************************/
808
809/*
810 * Returns:
811 * 0 ==> OK
812 * -1 ==> Error
813 */
814extern int
816 HTAB *hashp;
817{
818 u_int32_t old_bucket, new_bucket;
819 int dirsize, new_segnum, spare_ndx;
820
821#ifdef HASH_STATISTICS
822 hash_expansions++;
823#endif
824 new_bucket = ++hashp->MAX_BUCKET;
825 old_bucket = (hashp->MAX_BUCKET & hashp->LOW_MASK);
826
827 new_segnum = new_bucket >> hashp->SSHIFT;
828
829 /* Check if we need a new segment */
830 if (new_segnum >= hashp->nsegs) {
831 /* Check if we need to expand directory */
832 if (new_segnum >= hashp->DSIZE) {
833 /* Reallocate directory */
834 dirsize = hashp->DSIZE * sizeof(SEGMENT *);
835 if (!hash_realloc(&hashp->dir, dirsize, dirsize << 1))
836 return (-1);
837 hashp->DSIZE = dirsize << 1;
838 }
839 if ((hashp->dir[new_segnum] =
840 (SEGMENT)calloc(hashp->SGSIZE, sizeof(SEGMENT))) == NULL)
841 return (-1);
842 hashp->exsegs++;
843 hashp->nsegs++;
844 }
845 /*
846 * If the split point is increasing (MAX_BUCKET's log base 2
847 * * increases), we need to copy the current contents of the spare
848 * split bucket to the next bucket.
849 */
850 spare_ndx = __hash_log2(hashp->MAX_BUCKET + 1);
851 if (spare_ndx > hashp->OVFL_POINT) {
852 hashp->SPARES[spare_ndx] = hashp->SPARES[hashp->OVFL_POINT];
853 hashp->OVFL_POINT = spare_ndx;
854 }
855
856 if (new_bucket > (u_int32_t) hashp->HIGH_MASK) {
857 /* Starting a new doubling */
858 hashp->LOW_MASK = hashp->HIGH_MASK;
859 hashp->HIGH_MASK = new_bucket | hashp->LOW_MASK;
860 }
861 /* Relocate records to the new bucket */
862 return (__split_page(hashp, old_bucket, new_bucket));
863}
864
865/*
866 * If realloc guarantees that the pointer is not destroyed if the realloc
867 * fails, then this routine can go away.
868 */
869static void *
870hash_realloc(p_ptr, oldsize, newsize)
871 SEGMENT **p_ptr;
872 int oldsize, newsize;
873{
874 register void *p;
875
876 if ((p = malloc(newsize))) {
877 memmove(p, *p_ptr, oldsize);
878 memset((char *)p + oldsize, 0, newsize - oldsize);
879 free(*p_ptr);
880 *p_ptr = p;
881 }
882 return (p);
883}
884
885extern u_int32_t
886__call_hash(hashp, k, len)
887 HTAB *hashp;
888 char *k;
889 int len;
890{
891 int n, bucket;
892
893 n = hashp->hash(k, len);
894 bucket = n & hashp->HIGH_MASK;
895 if (bucket > hashp->MAX_BUCKET)
896 bucket = bucket & hashp->LOW_MASK;
897 return (bucket);
898}
899
900/*
901 * Allocate segment table. On error, destroy the table and set errno.
902 *
903 * Returns 0 on success
904 */
905static int
906alloc_segs(hashp, nsegs)
907 HTAB *hashp;
908 int nsegs;
909{
910 register int i;
911 register SEGMENT store;
912
913 int save_errno;
914
915 if ((hashp->dir =
916 (SEGMENT *)calloc(hashp->DSIZE, sizeof(SEGMENT *))) == NULL) {
917 save_errno = errno;
918 (void)hdestroy(hashp);
919 errno = save_errno;
920 return (-1);
921 }
922 /* Allocate segments */
923 if ((store =
924 (SEGMENT)calloc(nsegs << hashp->SSHIFT, sizeof(SEGMENT))) == NULL) {
925 save_errno = errno;
926 (void)hdestroy(hashp);
927 errno = save_errno;
928 return (-1);
929 }
930 for (i = 0; i < nsegs; i++, hashp->nsegs++)
931 hashp->dir[i] = &store[i << hashp->SSHIFT];
932 return (0);
933}
934
935#if BYTE_ORDER == LITTLE_ENDIAN
936/*
937 * Hashp->hdr needs to be byteswapped.
938 */
939static void
941 HASHHDR *srcp, *destp;
942{
943 int i;
944
945 P_32_COPY(srcp->magic, destp->magic);
946 P_32_COPY(srcp->version, destp->version);
947 P_32_COPY(srcp->lorder, destp->lorder);
948 P_32_COPY(srcp->bsize, destp->bsize);
949 P_32_COPY(srcp->bshift, destp->bshift);
950 P_32_COPY(srcp->dsize, destp->dsize);
951 P_32_COPY(srcp->ssize, destp->ssize);
952 P_32_COPY(srcp->sshift, destp->sshift);
953 P_32_COPY(srcp->ovfl_point, destp->ovfl_point);
954 P_32_COPY(srcp->last_freed, destp->last_freed);
955 P_32_COPY(srcp->max_bucket, destp->max_bucket);
956 P_32_COPY(srcp->high_mask, destp->high_mask);
957 P_32_COPY(srcp->low_mask, destp->low_mask);
958 P_32_COPY(srcp->ffactor, destp->ffactor);
959 P_32_COPY(srcp->nkeys, destp->nkeys);
960 P_32_COPY(srcp->hdrpages, destp->hdrpages);
961 P_32_COPY(srcp->h_charkey, destp->h_charkey);
962 for (i = 0; i < NCACHED; i++) {
963 P_32_COPY(srcp->spares[i], destp->spares[i]);
964 P_16_COPY(srcp->bitmaps[i], destp->bitmaps[i]);
965 }
966}
967
968static void
970 HTAB *hashp;
971{
972 HASHHDR *hdrp;
973 int i;
974
975 hdrp = &hashp->hdr;
976
977 M_32_SWAP(hdrp->magic);
978 M_32_SWAP(hdrp->version);
979 M_32_SWAP(hdrp->lorder);
980 M_32_SWAP(hdrp->bsize);
981 M_32_SWAP(hdrp->bshift);
982 M_32_SWAP(hdrp->dsize);
983 M_32_SWAP(hdrp->ssize);
984 M_32_SWAP(hdrp->sshift);
985 M_32_SWAP(hdrp->ovfl_point);
986 M_32_SWAP(hdrp->last_freed);
987 M_32_SWAP(hdrp->max_bucket);
988 M_32_SWAP(hdrp->high_mask);
989 M_32_SWAP(hdrp->low_mask);
990 M_32_SWAP(hdrp->ffactor);
991 M_32_SWAP(hdrp->nkeys);
992 M_32_SWAP(hdrp->hdrpages);
993 M_32_SWAP(hdrp->h_charkey);
994 for (i = 0; i < NCACHED; i++) {
995 M_32_SWAP(hdrp->spares[i]);
996 M_16_SWAP(hdrp->bitmaps[i]);
997 }
998}
999#endif
dflags
Definition: app_dictate.c:63
if(!yyg->yy_init)
Definition: ast_expr2f.c:854
#define calloc(a, b)
Definition: astmm.h:155
#define R_NOOVERWRITE
Definition: db.h:98
#define HASHVERSION
Definition: db.h:160
#define R_NEXT
Definition: db.h:97
#define R_FIRST
Definition: db.h:93
@ DB_HASH
Definition: db.h:103
#define R_CURSOR
Definition: db.h:91
#define HASHMAGIC
Definition: db.h:159
long int flag
Definition: f2c.h:83
static int len(struct ast_channel *chan, const char *cmd, char *data, char *buf, size_t buflen)
char * malloc()
void free()
static HTAB * init_hash(HTAB *hashp, const char *file, const HASHINFO *info)
Definition: hash.c:280
static void * hash_realloc(SEGMENT **p_ptr, int oldsize, int newsize)
Definition: hash.c:870
static int hdestroy(HTAB *hashp)
Definition: hash.c:397
static int init_htab(HTAB *hashp, int nelem)
Definition: hash.c:351
static int hash_access(HTAB *hashp, ACTION action, DBT *key, DBT *val)
Definition: hash.c:596
#define ABNORMAL
Definition: hash.c:86
static int hash_sync(DB *dbp, u_int32_t flags) const
Definition: hash.c:457
static int alloc_segs(HTAB *hashp, int nsegs)
Definition: hash.c:906
static int hash_seq(DB *dbp, DBT *key, DBT *data, u_int32_t flag) const
Definition: hash.c:725
static int hash_put(DB *dbp, DBT *key, const DBT *data, u_int32_t flag) const
Definition: hash.c:551
static int hash_close(DB *dbp)
Definition: hash.c:246
static int hash_get(DB *dbp, const DBT *key, DBT *data, u_int32_t flag) const
Definition: hash.c:534
static int flush_meta(HTAB *hashp)
Definition: hash.c:486
static int alloc_segs __P((HTAB *, int))
#define ERROR
Definition: hash.c:85
static void swap_header_copy(HASHHDR *srcp, HASHHDR *destp)
Definition: hash.c:940
static int hash_delete(DB *dbp, const DBT *key, u_int32_t flag) const
Definition: hash.c:573
static int hash_fd(DB *dbp) const
Definition: hash.c:262
#define SUCCESS
Definition: hash.c:84
#define RETURN_ERROR(ERR, LOC)
Definition: hash.c:81
#define OLDHASHVERSION
int __expand_table(HTAB *hashp)
Definition: hash.c:815
static void swap_header(HTAB *hashp)
Definition: hash.c:969
DB * __hash_open(char *file, int flags, int mode, const HASHINFO *info, int dflags) const
Definition: hash.c:96
u_int32_t __call_hash(HTAB *hashp, char *k, int len)
Definition: hash.c:886
#define OVFLPAGE
Definition: hash.h:266
#define BYTE_SHIFT
Definition: hash.h:137
#define DEF_DIRSIZE
Definition: hash.h:131
#define DEF_BUCKET_SIZE
Definition: hash.h:127
#define NCACHED
Definition: hash.h:85
#define OADDR_OF(S, O)
Definition: hash.h:169
#define DEF_SEGSIZE_SHIFT
Definition: hash.h:130
#define DEF_SEGSIZE
Definition: hash.h:129
#define DEF_BUCKET_SHIFT
Definition: hash.h:128
#define DEF_FFACTOR
Definition: hash.h:132
#define CHARKEY
Definition: hash.h:135
#define DEF_BUFSIZE
Definition: hash.h:126
#define REAL_KEY
Definition: hash.h:270
#define MAX_BSIZE
Definition: hash.h:123
#define BUF_PIN
Definition: hash.h:57
ACTION
Definition: hash.h:40
@ HASH_DELETE
Definition: hash.h:41
@ HASH_PUT
Definition: hash.h:41
@ HASH_PUTNEW
Definition: hash.h:41
@ HASH_GET
Definition: hash.h:41
#define MINHDRSIZE
Definition: hash.h:125
int __big_keydata(HTAB *hashp, BUFHEAD *bufp, DBT *key, DBT *val, int set)
Definition: hash_bigkey.c:507
int __find_bigpair(HTAB *hashp, BUFHEAD *bufp, int ndx, char *key, int size)
Definition: hash_bigkey.c:267
int __big_return(HTAB *hashp, BUFHEAD *bufp, int ndx, DBT *val, int set_current)
Definition: hash_bigkey.c:360
u_int16_t __find_last_page(HTAB *hashp, BUFHEAD **bpp)
Definition: hash_bigkey.c:319
void __buf_init(HTAB *hashp, int nbytes)
Definition: hash_buf.c:290
BUFHEAD * __get_buf(HTAB *hashp, u_int32_t addr, BUFHEAD *prev_bp, int newpage)
Definition: hash_buf.c:105
int __buf_free(HTAB *hashp, int do_free, int to_disk)
Definition: hash_buf.c:315
u_int32_t __hash_log2(u_int32_t num)
Definition: hash_log2.c:48
int __delpair(HTAB *hashp, BUFHEAD *bufp, int ndx)
Definition: hash_page.c:128
int __put_page(HTAB *hashp, char *p, u_int32_t bucket, int is_bucket, int is_bitmap)
Definition: hash_page.c:578
int __addel(HTAB *hashp, BUFHEAD *bufp, const DBT *key, const DBT *val)
Definition: hash_page.c:398
int __ibitmap(HTAB *hashp, int pnum, int nbits, int ndx)
Definition: hash_page.c:627
int __split_page(HTAB *hashp, u_int32_t obucket, u_int32_t nbucket)
Definition: hash_page.c:181
static DB * dbp
Definition: hsearch.c:49
static ENTRY retval
Definition: hsearch.c:50
unsigned int u_int32_t
#define BYTE_ORDER
#define BIG_ENDIAN
unsigned short u_int16_t
#define LITTLE_ENDIAN
#define DEBUG(a)
Definition: io.c:48
int errno
def info(msg)
#define NULL
Definition: resample.c:96
Definition: db.h:85
void * data
Definition: db.h:86
size_t size
Definition: db.h:87
Definition: db.h:163
Definition: db.h:129
DBTYPE type
Definition: db.h:130
void * internal
Definition: db.h:137
Definition: hash.h:47
char * page
Definition: hash.h:52
char flags
Definition: hash.h:53
Definition: hash.h:65
int spares[NCACHED]
Definition: hash.h:86
int bsize
Definition: hash.h:69
int high_mask
Definition: hash.h:78
int hdrpages
Definition: hash.h:83
int h_charkey
Definition: hash.h:84
int bshift
Definition: hash.h:70
int ovfl_point
Definition: hash.h:74
int magic
Definition: hash.h:66
int ffactor
Definition: hash.h:81
int nkeys
Definition: hash.h:82
u_int32_t lorder
Definition: hash.h:68
int low_mask
Definition: hash.h:79
int max_bucket
Definition: hash.h:77
int version
Definition: hash.h:67
int dsize
Definition: hash.h:71
int sshift
Definition: hash.h:73
int ssize
Definition: hash.h:72
int last_freed
Definition: hash.h:76
u_int16_t bitmaps[NCACHED]
Definition: hash.h:87
Definition: hash.h:91
int cbucket
Definition: hash.h:103
int save_file
Definition: hash.h:109
int new_file
Definition: hash.h:107
int fp
Definition: hash.h:99
int exsegs
Definition: hash.h:94
SEGMENT * dir
Definition: hash.h:117
u_int32_t * mapp[NCACHED]
Definition: hash.h:112
int nsegs
Definition: hash.h:93
HASHHDR hdr
Definition: hash.h:92
int errnum
Definition: hash.h:105
int nmaps
Definition: hash.h:113
BUFHEAD * cpage
Definition: hash.h:102
int cndx
Definition: hash.h:104
int flags
Definition: hash.h:98
Definition: ast_expr2.c:325
#define EFTYPE
#define MAX(a, b)
Definition: utils.h:233