37 #if defined(LIBC_SCCS) && !defined(lint)
38 static char sccsid[] =
"@(#)hash.c 8.9 (Berkeley) 6/16/94";
41 #include <sys/param.h>
54 #include "../include/db.h"
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 *));
72 static int init_htab __P((
HTAB *,
int));
73 #if BYTE_ORDER == LITTLE_ENDIAN
74 static void swap_header __P((
HTAB *));
79 #define MOD(x, y) ((x) & ((y) - 1))
81 #define RETURN_ERROR(ERR, LOC) { save_errno = ERR; goto LOC; }
88 #ifdef HASH_STATISTICS
89 int hash_accesses, hash_collisions, hash_expansions, hash_overflows;
96 __hash_open(file, flags, mode, info, dflags)
98 int flags, mode, dflags;
104 int bpages, hdrsize, new_table, nsegs, save_errno;
106 if ((flags & O_ACCMODE) == O_WRONLY) {
111 if (!(hashp = (
HTAB *)calloc(1,
sizeof(
HTAB))))
121 hashp->flags = flags;
124 if (!file || (flags & O_TRUNC) ||
125 (stat(file, &statbuf) && (errno == ENOENT))) {
131 if ((hashp->fp = open(file, flags, mode)) == -1)
132 RETURN_ERROR(errno, error0);
133 (void)fcntl(hashp->fp, F_SETFD, 1);
136 if (!(hashp = init_hash(hashp, file, info)))
137 RETURN_ERROR(errno, error1);
140 if (info && info->hash)
141 hashp->hash = info->hash;
143 hashp->hash = __default_hash;
145 hdrsize = read(hashp->fp, &hashp->hdr,
sizeof(
HASHHDR));
146 #if BYTE_ORDER == LITTLE_ENDIAN
150 RETURN_ERROR(errno, error1);
151 if (hdrsize !=
sizeof(
HASHHDR))
152 RETURN_ERROR(EFTYPE, error1);
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);
168 nsegs = (hashp->MAX_BUCKET + 1 + hashp->SGSIZE - 1) /
171 if (alloc_segs(hashp, nsegs))
178 bpages = (hashp->SPARES[hashp->OVFL_POINT] +
179 (hashp->BSIZE << BYTE_SHIFT) - 1) >>
180 (hashp->BSHIFT + BYTE_SHIFT);
182 hashp->nmaps = bpages;
183 (void)memset(&hashp->mapp[0], 0, bpages *
sizeof(u_int32_t *));
187 if (info && info->cachesize)
188 __buf_init(hashp, info->cachesize);
190 __buf_init(hashp, DEF_BUFSIZE);
192 hashp->new_file = new_table;
193 hashp->save_file = file && (hashp->flags & O_ACCMODE) != O_RDONLY;
195 if (!(dbp = (
DB *)malloc(
sizeof(
DB)))) {
201 dbp->internal = hashp;
202 dbp->close = hash_close;
203 dbp->del = hash_delete;
208 dbp->sync = hash_sync;
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",
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);
230 #ifdef HASH_STATISTICS
231 hash_overflows = hash_accesses = hash_collisions = hash_expansions = 0;
237 (void)close(hashp->fp);
255 hashp = (
HTAB *)dbp->internal;
256 retval = hdestroy(hashp);
270 hashp = (
HTAB *)dbp->internal;
271 if (hashp->fp == -1) {
280 init_hash(hashp, file, info)
285 #ifdef _STATBUF_ST_BLKSIZE
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));
304 #ifdef _STATBUF_ST_BLKSIZE
306 if (stat(file, &statbuf))
308 hashp->BSIZE = statbuf.st_blksize;
309 hashp->BSHIFT = __hash_log2(hashp->BSIZE);
316 hashp->BSHIFT = __hash_log2(info->bsize);
317 hashp->BSIZE = 1 << hashp->BSHIFT;
318 if (hashp->BSIZE > MAX_BSIZE) {
324 hashp->FFACTOR = info->ffactor;
326 hashp->hash = info->hash;
330 if (info->lorder != BIG_ENDIAN &&
331 info->lorder != LITTLE_ENDIAN) {
335 hashp->LORDER = info->lorder;
339 if (init_htab(hashp, nelem))
351 init_htab(hashp, nelem)
355 register int nbuckets, nsegs;
363 nelem = (nelem - 1) / hashp->FFACTOR + 1;
365 l2 = __hash_log2(MAX(nelem, 2));
368 hashp->SPARES[l2] = l2 + 1;
369 hashp->SPARES[l2 + 1] = l2 + 1;
370 hashp->OVFL_POINT = l2;
371 hashp->LAST_FREED = 2;
374 if (__ibitmap(hashp, OADDR_OF(l2, 1), l2 + 1, 0))
377 hashp->MAX_BUCKET = hashp->LOW_MASK = nbuckets - 1;
378 hashp->HIGH_MASK = (nbuckets << 1) - 1;
379 hashp->HDRPAGES = ((MAX(
sizeof(
HASHHDR), MINHDRSIZE) - 1) >>
382 nsegs = (nbuckets - 1) / hashp->SGSIZE + 1;
383 nsegs = 1 << __hash_log2(nsegs);
385 if (nsegs > hashp->DSIZE)
386 hashp->DSIZE = nsegs;
387 return (alloc_segs(hashp, nsegs));
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",
409 (void)fprintf(stderr,
"hdestroy: overflows %ld\n",
411 (void)fprintf(stderr,
"keys %ld maxp %d segmentcount %d\n",
412 hashp->NKEYS, hashp->MAX_BUCKET, hashp->nsegs);
414 for (i = 0; i < NCACHED; i++)
415 (
void)fprintf(stderr,
416 "spares[%d] = %d\n", i, hashp->SPARES[i]);
422 if (__buf_free(hashp, 1, hashp->save_file))
427 while (hashp->exsegs--)
428 free(hashp->dir[--hashp->nsegs]);
431 if (flush_meta(hashp) && !save_errno)
434 for (i = 0; i < hashp->nmaps; i++)
436 free(hashp->mapp[i]);
439 (void)close(hashp->fp);
457 hash_sync(dbp, flags)
471 hashp = (
HTAB *)dbp->internal;
472 if (!hashp->save_file)
474 if (__buf_free(hashp, 0, 1) || flush_meta(hashp))
490 #if BYTE_ORDER == LITTLE_ENDIAN
495 if (!hashp->save_file)
497 hashp->MAGIC = HASHMAGIC;
498 hashp->VERSION = HASHVERSION;
499 hashp->H_CHARKEY = hashp->hash(CHARKEY,
sizeof(CHARKEY));
503 #if BYTE_ORDER == LITTLE_ENDIAN
505 swap_header_copy(&hashp->hdr, whdrp);
507 if ((lseek(fp, (off_t)0, SEEK_SET) == -1) ||
508 ((wsize = write(fp, whdrp,
sizeof(
HASHHDR))) == -1))
511 if (wsize !=
sizeof(
HASHHDR)) {
513 hashp->errnum = errno;
516 for (i = 0; i < NCACHED; i++)
518 if (__put_page(hashp, (
char *)hashp->mapp[i],
519 hashp->BITMAPS[i], 0, 1))
534 hash_get(dbp, key, data, flag)
542 hashp = (
HTAB *)dbp->internal;
544 hashp->errnum = errno = EINVAL;
547 return (hash_access(hashp, HASH_GET, (
DBT *)key, data));
551 hash_put(dbp, key, data, flag)
559 hashp = (
HTAB *)dbp->internal;
560 if (flag && flag != R_NOOVERWRITE) {
561 hashp->errnum = errno = EINVAL;
564 if ((hashp->flags & O_ACCMODE) == O_RDONLY) {
565 hashp->errnum = errno = EPERM;
568 return (hash_access(hashp, flag == R_NOOVERWRITE ?
569 HASH_PUTNEW : HASH_PUT, (
DBT *)key, (
DBT *)data));
573 hash_delete(dbp, key, flag)
580 hashp = (
HTAB *)dbp->internal;
581 if (flag && flag != R_CURSOR) {
582 hashp->errnum = errno = EINVAL;
585 if ((hashp->flags & O_ACCMODE) == O_RDONLY) {
586 hashp->errnum = errno = EPERM;
589 return (hash_access(hashp, HASH_DELETE, (
DBT *)key, NULL));
596 hash_access(hashp, action, key,
val)
603 register u_int16_t *bp;
604 register int n, ndx, off, size;
608 #ifdef HASH_STATISTICS
614 kp = (
char *)key->data;
615 rbufp = __get_buf(hashp, __call_hash(hashp, kp, size), NULL, 0);
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) {
625 if (size == off - *bp &&
626 memcmp(kp, rbufp->page + *bp, size) == 0)
629 #ifdef HASH_STATISTICS
634 }
else if (bp[1] == OVFLPAGE) {
635 rbufp = __get_buf(hashp, *bp, rbufp, 0);
637 save_bufp->flags &= ~BUF_PIN;
641 bp = (u_int16_t *)rbufp->page;
645 }
else if (bp[1] < REAL_KEY) {
647 __find_bigpair(hashp, rbufp, ndx, kp, size)) > 0)
652 __find_last_page(hashp, &bufp))) {
657 rbufp = __get_buf(hashp, pageno, bufp, 0);
659 save_bufp->flags &= ~BUF_PIN;
663 bp = (u_int16_t *)rbufp->page;
668 save_bufp->flags &= ~BUF_PIN;
677 if (__addel(hashp, rbufp, key, val)) {
678 save_bufp->flags &= ~BUF_PIN;
681 save_bufp->flags &= ~BUF_PIN;
687 save_bufp->flags &= ~BUF_PIN;
694 save_bufp->flags &= ~BUF_PIN;
697 bp = (u_int16_t *)rbufp->page;
698 if (bp[ndx + 1] < REAL_KEY) {
699 if (__big_return(hashp, rbufp, ndx, val, 0))
702 val->data = (u_char *)rbufp->page + (
int)bp[ndx + 1];
703 val->size = bp[ndx] - bp[ndx + 1];
707 if ((__delpair(hashp, rbufp, ndx)) ||
708 (__addel(hashp, rbufp, key, val))) {
709 save_bufp->flags &= ~BUF_PIN;
714 if (__delpair(hashp, rbufp, ndx))
720 save_bufp->flags &= ~BUF_PIN;
725 hash_seq(dbp, key, data, flag)
730 register u_int32_t bucket;
735 hashp = (
HTAB *)dbp->internal;
736 if (flag && flag != R_FIRST && flag != R_NEXT) {
737 hashp->errnum = errno = EINVAL;
740 #ifdef HASH_STATISTICS
743 if ((hashp->cbucket < 0) || (flag == R_FIRST)) {
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);
758 bp = (u_int16_t *)bufp->page;
762 hashp->cbucket = bucket;
763 if (hashp->cbucket > hashp->MAX_BUCKET) {
768 bp = (u_int16_t *)hashp->cpage->page;
774 while (bp[hashp->cndx + 1] == OVFLPAGE) {
775 bufp = hashp->cpage =
776 __get_buf(hashp, bp[hashp->cndx], bufp, 0);
779 bp = (u_int16_t *)(bufp->page);
788 if (bp[ndx + 1] < REAL_KEY) {
789 if (__big_keydata(hashp, bufp, key, data, 1))
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];
815 __expand_table(hashp)
818 u_int32_t old_bucket, new_bucket;
819 int dirsize, new_segnum, spare_ndx;
821 #ifdef HASH_STATISTICS
824 new_bucket = ++hashp->MAX_BUCKET;
825 old_bucket = (hashp->MAX_BUCKET & hashp->LOW_MASK);
827 new_segnum = new_bucket >> hashp->SSHIFT;
830 if (new_segnum >= hashp->nsegs) {
832 if (new_segnum >= hashp->DSIZE) {
834 dirsize = hashp->DSIZE *
sizeof(
SEGMENT *);
835 if (!hash_realloc(&hashp->dir, dirsize, dirsize << 1))
837 hashp->DSIZE = dirsize << 1;
839 if ((hashp->dir[new_segnum] =
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;
856 if (new_bucket > (u_int32_t) hashp->HIGH_MASK) {
858 hashp->LOW_MASK = hashp->HIGH_MASK;
859 hashp->HIGH_MASK = new_bucket | hashp->LOW_MASK;
862 return (__split_page(hashp, old_bucket, new_bucket));
870 hash_realloc(p_ptr, oldsize, newsize)
872 int oldsize, newsize;
876 if ((p = malloc(newsize))) {
877 memmove(p, *p_ptr, oldsize);
878 memset((
char *)p + oldsize, 0, newsize - oldsize);
886 __call_hash(hashp, k, len)
893 n = hashp->hash(k, len);
894 bucket = n & hashp->HIGH_MASK;
895 if (bucket > hashp->MAX_BUCKET)
896 bucket = bucket & hashp->LOW_MASK;
906 alloc_segs(hashp, nsegs)
918 (void)hdestroy(hashp);
924 (
SEGMENT)calloc(nsegs << hashp->SSHIFT,
sizeof(
SEGMENT))) == NULL) {
926 (void)hdestroy(hashp);
930 for (i = 0; i < nsegs; i++, hashp->nsegs++)
931 hashp->dir[i] = &store[i << hashp->SSHIFT];
935 #if BYTE_ORDER == LITTLE_ENDIAN
940 swap_header_copy(srcp, destp)
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]);
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]);