Asterisk - The Open Source Telephony Project  GIT-master-4a4f1a5
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)
38 static 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 
59 static int alloc_segs __P((HTAB *, int));
60 static int flush_meta __P((HTAB *));
61 static int hash_access __P((HTAB *, ACTION, DBT *, DBT *));
62 static int hash_close __P((DB *));
63 static int hash_delete __P((const DB *, const DBT *, u_int32_t));
64 static int hash_fd __P((const DB *));
65 static int hash_get __P((const DB *, const DBT *, DBT *, u_int32_t));
66 static int hash_put __P((const DB *, DBT *, const DBT *, u_int32_t));
67 static void *hash_realloc __P((SEGMENT **, int, int));
68 static int hash_seq __P((const DB *, DBT *, DBT *, u_int32_t));
69 static int hash_sync __P((const DB *, u_int32_t));
70 static int hdestroy __P((HTAB *));
71 static HTAB *init_hash __P((HTAB *, const char *, const HASHINFO *));
72 static int init_htab __P((HTAB *, int));
73 #if BYTE_ORDER == LITTLE_ENDIAN
74 static void swap_header __P((HTAB *));
75 static 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
89 int hash_accesses, hash_collisions, hash_expansions, hash_overflows;
90 #endif
91 
92 /************************** INTERFACE ROUTINES ***************************/
93 /* OPEN/CLOSE */
94 
95 extern 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 
235 error1:
236  if (hashp != NULL)
237  (void)close(hashp->fp);
238 
239 error0:
240  free(hashp);
241  errno = save_errno;
242  return (NULL);
243 }
244 
245 static 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 
261 static 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 **********************/
279 static 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  */
350 static int
351 init_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  */
396 static int
397 hdestroy(hashp)
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  */
456 static int
457 hash_sync(dbp, flags)
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  */
485 static 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  */
533 static int
534 hash_get(dbp, key, data, flag)
535  const DB *dbp;
536  const DBT *key;
537  DBT *data;
538  u_int32_t flag;
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 
550 static int
551 hash_put(dbp, key, data, flag)
552  const DB *dbp;
553  DBT *key;
554  const DBT *data;
555  u_int32_t flag;
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 
572 static 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  */
595 static int
596 hash_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 
691 found:
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 
724 static int
725 hash_seq(dbp, key, data, flag)
726  const DB *dbp;
727  DBT *key, *data;
728  u_int32_t flag;
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  */
814 extern 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  */
869 static void *
870 hash_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 
885 extern 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  */
905 static int
906 alloc_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  */
939 static void
940 swap_header_copy(srcp, destp)
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 
968 static 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:868
#define calloc(a, b)
Definition: astmm.h:157
#define DEBUG
Definition: chan_alsa.c:85
#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 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 HTAB * init_hash(HTAB *hashp, const char *file, const HASHINFO *info)
Definition: hash.c:280
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
static void * hash_realloc(SEGMENT **p_ptr, int oldsize, int newsize)
Definition: hash.c:870
#define OLDHASHVERSION
DB * __hash_open(char *file, int flags, int mode, const HASHINFO *info, int dflags) const
Definition: hash.c:96
int __expand_table(HTAB *hashp)
Definition: hash.c:815
static void swap_header(HTAB *hashp)
Definition: hash.c:969
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
int __buf_free(HTAB *hashp, int do_free, int to_disk)
Definition: hash_buf.c:315
BUFHEAD * __get_buf(HTAB *hashp, u_int32_t addr, BUFHEAD *prev_bp, int newpage)
Definition: hash_buf.c:105
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
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:228