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-rw-r--r--win32/sdbm.c981
1 files changed, 0 insertions, 981 deletions
diff --git a/win32/sdbm.c b/win32/sdbm.c
deleted file mode 100644
index d2d2171875..0000000000
--- a/win32/sdbm.c
+++ /dev/null
@@ -1,981 +0,0 @@
-/*
- * sdbm - ndbm work-alike hashed database library
- * based on Per-Aake Larson's Dynamic Hashing algorithms. BIT 18 (1978).
- * author: oz@nexus.yorku.ca
- * status: public domain.
- *
- * core routines
- */
-
-#ifndef lint
-/*char sdbm_rcsid[] = "$Id: sdbm.c,v 1.16 90/12/13 13:01:31 oz Exp $";*/
-#endif
-
-#include "sdbm.h"
-
-/*#include "tune.h"*/
-/*
- * sdbm - ndbm work-alike hashed database library
- * tuning and portability constructs [not nearly enough]
- * author: oz@nexus.yorku.ca
- */
-
-#define BYTESIZ 8
-
-#ifdef SVID
-#include <unistd.h>
-#endif
-
-#ifdef __GO32__
-#include <unistd.h>
-#endif
-
-#ifdef BSD42
-#define SEEK_SET L_SET
-#define memset(s,c,n) bzero(s, n) /* only when c is zero */
-#define memcpy(s1,s2,n) bcopy(s2, s1, n)
-#define memcmp(s1,s2,n) bcmp(s1,s2,n)
-#endif
-
-/*
- * important tuning parms (hah)
- */
-
-#define SEEDUPS /* always detect duplicates */
-#define BADMESS /* generate a message for worst case:
- cannot make room after SPLTMAX splits */
-/*
- * misc
- */
-#ifdef DEBUG
-#define debug(x) printf x
-#else
-#define debug(x)
-#endif
-
-#ifdef BIG_E
-#define GET_SHORT(p, i) (((unsigned)((unsigned char *)(p))[(i)*2] << 8) + (((unsigned char *)(p))[(i)*2 + 1]))
-#define PUT_SHORT(p, i, s) (((unsigned char *)(p))[(i)*2] = (unsigned char)((s) >> 8), ((unsigned char *)(p))[(i)*2 + 1] = (unsigned char)(s))
-#else
-#define GET_SHORT(p, i) ((p)[i])
-#define PUT_SHORT(p, i, s) ((p)[i] = (s))
-#endif
-
-/*#include "pair.h"*/
-static int fitpair proto((char *, int));
-static void putpair proto((char *, datum, datum));
-static datum getpair proto((char *, datum));
-static int delpair proto((char *, datum));
-static int chkpage proto((char *));
-static datum getnkey proto((char *, int));
-static void splpage proto((char *, char *, long));
-#ifdef SEEDUPS
-static int duppair proto((char *, datum));
-#endif
-
-#ifdef MSDOS
-#include <stdio.h>
-#include <stdlib.h>
-#include <io.h>
-#endif
-#include <sys/types.h>
-#include <sys/stat.h>
-#ifdef BSD42
-#include <sys/file.h>
-#else
-#include <fcntl.h>
-/*#include <memory.h>*/
-#endif
-#ifndef O_BINARY
-#define O_BINARY 0
-#endif
-
-#include <errno.h>
-#ifndef EPERM
-#define EPERM EACCES
-#endif
-#include <string.h>
-
-#ifdef __STDC__
-#include <stddef.h>
-#endif
-
-#ifndef NULL
-#define NULL 0
-#endif
-
-/*
- * externals
- */
-#ifndef sun
-#ifndef MSDOS
-extern int errno;
-#endif
-#endif
-
-/*
- * forward
- */
-static int getdbit proto((DBM *, long));
-static int setdbit proto((DBM *, long));
-static int getpage proto((DBM *, long));
-static datum getnext proto((DBM *));
-static int makroom proto((DBM *, long, int));
-
-/*
- * useful macros
- */
-#define bad(x) ((x).dptr == NULL || (x).dsize < 0)
-#define exhash(item) dbm_hash((item).dptr, (item).dsize)
-#define ioerr(db) ((db)->flags |= DBM_IOERR)
-
-#define OFF_PAG(off) (long) (off) * PBLKSIZ
-#define OFF_DIR(off) (long) (off) * DBLKSIZ
-
-static long masks[] = {
- 000000000000L, 000000000001L, 000000000003L,
- 000000000007L, 000000000017L, 000000000037L,
- 000000000077L, 000000000177L, 000000000377L,
- 000000000777L, 000000001777L, 000000003777L,
- 000000007777L, 000000017777L, 000000037777L,
- 000000077777L, 000000177777L, 000000377777L,
- 000000777777L, 000001777777L, 000003777777L,
- 000007777777L, 000017777777L, 000037777777L,
- 000077777777L, 000177777777L, 000377777777L,
- 000777777777L, 001777777777L, 003777777777L,
- 007777777777L, 017777777777L
-};
-
-datum nullitem = {NULL, 0};
-
-DBM *
-dbm_open(file, flags, mode)
-register char *file;
-register int flags;
-register int mode;
-{
- register DBM *db;
- register char *dirname;
- register char *pagname;
- register int n;
-
- if (file == NULL || !*file)
- return errno = EINVAL, (DBM *) NULL;
-/*
- * need space for two seperate filenames
- */
- n = strlen(file) * 2 + strlen(DIRFEXT) + strlen(PAGFEXT) + 2;
-
- if ((dirname = malloc((unsigned) n)) == NULL)
- return errno = ENOMEM, (DBM *) NULL;
-/*
- * build the file names
- */
- dirname = strcat(strcpy(dirname, file), DIRFEXT);
- pagname = strcpy(dirname + strlen(dirname) + 1, file);
- pagname = strcat(pagname, PAGFEXT);
-
- db = dbm_prep(dirname, pagname, flags, mode);
- free((char *) dirname);
- return db;
-}
-
-DBM *
-dbm_prep(dirname, pagname, flags, mode)
-char *dirname;
-char *pagname;
-int flags;
-int mode;
-{
- register DBM *db;
- struct stat dstat;
-
- if ((db = (DBM *) malloc(sizeof(DBM))) == NULL)
- return errno = ENOMEM, (DBM *) NULL;
-
- db->flags = 0;
- db->hmask = 0;
- db->blkptr = 0;
- db->keyptr = 0;
-/*
- * adjust user flags so that WRONLY becomes RDWR,
- * as required by this package. Also set our internal
- * flag for RDONLY.
- */
- if (flags & O_WRONLY)
- flags = (flags & ~O_WRONLY) | O_RDWR;
- if (flags & O_RDONLY)
- db->flags = DBM_RDONLY;
-/*
- * open the files in sequence, and stat the dirfile.
- * If we fail anywhere, undo everything, return NULL.
- */
-#ifdef MSDOS
- flags |= O_BINARY;
-#endif
- if ((db->pagf = open(pagname, flags, mode)) > -1) {
- if ((db->dirf = open(dirname, flags, mode)) > -1) {
-/*
- * need the dirfile size to establish max bit number.
- */
- if (fstat(db->dirf, &dstat) == 0) {
-/*
- * zero size: either a fresh database, or one with a single,
- * unsplit data page: dirpage is all zeros.
- */
- db->dirbno = (!dstat.st_size) ? 0 : -1;
- db->pagbno = -1;
- db->maxbno = dstat.st_size * (long) BYTESIZ;
-
- (void) memset(db->pagbuf, 0, PBLKSIZ);
- (void) memset(db->dirbuf, 0, DBLKSIZ);
- /*
- * success
- */
- return db;
- }
- (void) close(db->dirf);
- }
- (void) close(db->pagf);
- }
- free((char *) db);
- return (DBM *) NULL;
-}
-
-void
-dbm_close(db)
-register DBM *db;
-{
- if (db == NULL)
- errno = EINVAL;
- else {
- (void) close(db->dirf);
- (void) close(db->pagf);
- free((char *) db);
- }
-}
-
-datum
-dbm_fetch(db, key)
-register DBM *db;
-datum key;
-{
- if (db == NULL || bad(key))
- return errno = EINVAL, nullitem;
-
- if (getpage(db, exhash(key)))
- return getpair(db->pagbuf, key);
-
- return ioerr(db), nullitem;
-}
-
-int
-dbm_delete(db, key)
-register DBM *db;
-datum key;
-{
- if (db == NULL || bad(key))
- return errno = EINVAL, -1;
- if (dbm_rdonly(db))
- return errno = EPERM, -1;
-
- if (getpage(db, exhash(key))) {
- if (!delpair(db->pagbuf, key))
- return -1;
-/*
- * update the page file
- */
- if (lseek(db->pagf, OFF_PAG(db->pagbno), SEEK_SET) < 0
- || write(db->pagf, db->pagbuf, PBLKSIZ) < 0)
- return ioerr(db), -1;
-
- return 0;
- }
-
- return ioerr(db), -1;
-}
-
-int
-dbm_store(db, key, val, flags)
-register DBM *db;
-datum key;
-datum val;
-int flags;
-{
- int need;
- register long hash;
-
- if (db == NULL || bad(key))
- return errno = EINVAL, -1;
- if (dbm_rdonly(db))
- return errno = EPERM, -1;
-
- need = key.dsize + val.dsize;
-/*
- * is the pair too big (or too small) for this database ??
- */
- if (need < 0 || need > PAIRMAX)
- return errno = EINVAL, -1;
-
- if (getpage(db, (hash = exhash(key)))) {
-/*
- * if we need to replace, delete the key/data pair
- * first. If it is not there, ignore.
- */
- if (flags == DBM_REPLACE)
- (void) delpair(db->pagbuf, key);
-#ifdef SEEDUPS
- else if (duppair(db->pagbuf, key))
- return 1;
-#endif
-/*
- * if we do not have enough room, we have to split.
- */
- if (!fitpair(db->pagbuf, need))
- if (!makroom(db, hash, need))
- return ioerr(db), -1;
-/*
- * we have enough room or split is successful. insert the key,
- * and update the page file.
- */
- (void) putpair(db->pagbuf, key, val);
-
- if (lseek(db->pagf, OFF_PAG(db->pagbno), SEEK_SET) < 0
- || write(db->pagf, db->pagbuf, PBLKSIZ) < 0)
- return ioerr(db), -1;
- /*
- * success
- */
- return 0;
- }
-
- return ioerr(db), -1;
-}
-
-/*
- * makroom - make room by splitting the overfull page
- * this routine will attempt to make room for SPLTMAX times before
- * giving up.
- */
-static int
-makroom(db, hash, need)
-register DBM *db;
-long hash;
-int need;
-{
- long newp;
- char twin[PBLKSIZ];
-#ifdef MSDOS
- char zer[PBLKSIZ];
-#endif
- char *pag = db->pagbuf;
- char *new = twin;
- register int smax = SPLTMAX;
- long oldtail;
-
- do {
-/*
- * split the current page
- */
- (void) splpage(pag, new, db->hmask + 1);
-/*
- * address of the new page
- */
- newp = (hash & db->hmask) | (db->hmask + 1);
- debug(("newp: %ld\n", newp));
-/*
- * write delay, read avoidence/cache shuffle:
- * select the page for incoming pair: if key is to go to the new page,
- * write out the previous one, and copy the new one over, thus making
- * it the current page. If not, simply write the new page, and we are
- * still looking at the page of interest. current page is not updated
- * here, as dbm_store will do so, after it inserts the incoming pair.
- */
-
-#ifdef MSDOS
- /*
- * Fill hole with 0 if made it.
- * (hole is NOT read as 0)
- */
- oldtail = lseek(db->pagf, 0L, SEEK_END);
- memset(zer, 0, PBLKSIZ);
- while (OFF_PAG(newp) > oldtail) {
- if (lseek(db->pagf, 0L, SEEK_END) < 0 ||
- write(db->pagf, zer, PBLKSIZ) < 0) {
-
- return 0;
- }
- oldtail += PBLKSIZ;
- }
-#endif
-
- if (hash & (db->hmask + 1)) {
- if (lseek(db->pagf, OFF_PAG(db->pagbno), SEEK_SET) < 0
- || write(db->pagf, db->pagbuf, PBLKSIZ) < 0)
- return 0;
- db->pagbno = newp;
- (void) memcpy(pag, new, PBLKSIZ);
- }
- else if (lseek(db->pagf, OFF_PAG(newp), SEEK_SET) < 0
- || write(db->pagf, new, PBLKSIZ) < 0)
- return 0;
-
- if (!setdbit(db, db->curbit))
- return 0;
-/*
- * see if we have enough room now
- */
- if (fitpair(pag, need))
- return 1;
-/*
- * try again... update curbit and hmask as getpage would have
- * done. because of our update of the current page, we do not
- * need to read in anything. BUT we have to write the current
- * [deferred] page out, as the window of failure is too great.
- */
- db->curbit = 2 * db->curbit +
- ((hash & (db->hmask + 1)) ? 2 : 1);
- db->hmask |= (db->hmask + 1);
-
- if (lseek(db->pagf, OFF_PAG(db->pagbno), SEEK_SET) < 0
- || write(db->pagf, db->pagbuf, PBLKSIZ) < 0)
- return 0;
-
- } while (--smax);
-/*
- * if we are here, this is real bad news. After SPLTMAX splits,
- * we still cannot fit the key. say goodnight.
- */
-#ifdef BADMESS
- (void) write(2, "sdbm: cannot insert after SPLTMAX attempts.\n", 44);
-#endif
- return 0;
-
-}
-
-/*
- * the following two routines will break if
- * deletions aren't taken into account. (ndbm bug)
- */
-datum
-dbm_firstkey(db)
-register DBM *db;
-{
- if (db == NULL)
- return errno = EINVAL, nullitem;
-/*
- * start at page 0
- */
- (void) memset(db->pagbuf, 0, PBLKSIZ);
- if (lseek(db->pagf, OFF_PAG(0), SEEK_SET) < 0
- || read(db->pagf, db->pagbuf, PBLKSIZ) < 0)
- return ioerr(db), nullitem;
- db->pagbno = 0;
- db->blkptr = 0;
- db->keyptr = 0;
-
- return getnext(db);
-}
-
-datum
-dbm_nextkey(db)
-register DBM *db;
-{
- if (db == NULL)
- return errno = EINVAL, nullitem;
- return getnext(db);
-}
-
-/*
- * all important binary trie traversal
- */
-static int
-getpage(db, hash)
-register DBM *db;
-register long hash;
-{
- register int hbit;
- register long dbit;
- register long pagb;
-
- dbit = 0;
- hbit = 0;
- while (dbit < db->maxbno && getdbit(db, dbit))
- dbit = 2 * dbit + ((hash & ((long) 1 << hbit++)) ? 2 : 1);
-
- debug(("dbit: %d...", dbit));
-
- db->curbit = dbit;
- db->hmask = masks[hbit];
-
- pagb = hash & db->hmask;
-/*
- * see if the block we need is already in memory.
- * note: this lookaside cache has about 10% hit rate.
- */
- if (pagb != db->pagbno) {
-/*
- * note: here, we assume a "hole" is read as 0s.
- * if not, must zero pagbuf first.
- */
- (void) memset(db->pagbuf, 0, PBLKSIZ);
-
- if (lseek(db->pagf, OFF_PAG(pagb), SEEK_SET) < 0
- || read(db->pagf, db->pagbuf, PBLKSIZ) < 0)
- return 0;
- if (!chkpage(db->pagbuf)) {
- return 0;
- }
- db->pagbno = pagb;
-
- debug(("pag read: %d\n", pagb));
- }
- return 1;
-}
-
-static int
-getdbit(db, dbit)
-register DBM *db;
-register long dbit;
-{
- register long c;
- register long dirb;
-
- c = dbit / BYTESIZ;
- dirb = c / DBLKSIZ;
-
- if (dirb != db->dirbno) {
- if (lseek(db->dirf, OFF_DIR(dirb), SEEK_SET) < 0
- || read(db->dirf, db->dirbuf, DBLKSIZ) < 0)
- return 0;
- db->dirbno = dirb;
-
- debug(("dir read: %d\n", dirb));
- }
-
- return db->dirbuf[c % DBLKSIZ] & (1 << (dbit % BYTESIZ));
-}
-
-static int
-setdbit(db, dbit)
-register DBM *db;
-register long dbit;
-{
- register long c;
- register long dirb;
-
- c = dbit / BYTESIZ;
- dirb = c / DBLKSIZ;
-
- if (dirb != db->dirbno) {
- if (lseek(db->dirf, OFF_DIR(dirb), SEEK_SET) < 0
- || read(db->dirf, db->dirbuf, DBLKSIZ) < 0)
- return 0;
- db->dirbno = dirb;
-
- debug(("dir read: %d\n", dirb));
- }
-
- db->dirbuf[c % DBLKSIZ] |= (1 << (dbit % BYTESIZ));
-
- if (dbit >= db->maxbno)
- db->maxbno += (long) DBLKSIZ * BYTESIZ;
-
- if (lseek(db->dirf, OFF_DIR(dirb), SEEK_SET) < 0
- || write(db->dirf, db->dirbuf, DBLKSIZ) < 0)
- return 0;
-
- return 1;
-}
-
-/*
- * getnext - get the next key in the page, and if done with
- * the page, try the next page in sequence
- */
-static datum
-getnext(db)
-register DBM *db;
-{
- datum key;
-
- for (;;) {
- db->keyptr++;
- key = getnkey(db->pagbuf, db->keyptr);
- if (key.dptr != NULL)
- return key;
-/*
- * we either run out, or there is nothing on this page..
- * try the next one... If we lost our position on the
- * file, we will have to seek.
- */
- db->keyptr = 0;
- if (db->pagbno != db->blkptr++)
- if (lseek(db->pagf, OFF_PAG(db->blkptr), SEEK_SET) < 0)
- break;
- db->pagbno = db->blkptr;
- if (read(db->pagf, db->pagbuf, PBLKSIZ) <= 0)
- break;
- if (!chkpage(db->pagbuf)) {
- break;
- }
- }
-
- return ioerr(db), nullitem;
-}
-
-/* pair.c */
-/*
- * sdbm - ndbm work-alike hashed database library
- * based on Per-Aake Larson's Dynamic Hashing algorithms. BIT 18 (1978).
- * author: oz@nexus.yorku.ca
- * status: public domain.
- *
- * page-level routines
- */
-
-#ifndef lint
-/*char pair_rcsid[] = "$Id: sdbm.c,v 1.1.1.1.2.1 1998/01/16 12:36:12 matz Exp $";*/
-#endif
-
-#ifndef BSD42
-/*#include <memory.h>*/
-#endif
-
-#define exhash(item) dbm_hash((item).dptr, (item).dsize)
-
-/*
- * forward
- */
-static int seepair proto((char *, int, char *, int));
-
-/*
- * page format:
- * +------------------------------+
- * ino | n | keyoff | datoff | keyoff |
- * +------------+--------+--------+
- * | datoff | - - - ----> |
- * +--------+---------------------+
- * | F R E E A R E A |
- * +--------------+---------------+
- * | <---- - - - | data |
- * +--------+-----+----+----------+
- * | key | data | key |
- * +--------+----------+----------+
- *
- * calculating the offsets for free area: if the number
- * of entries (ino[0]) is zero, the offset to the END of
- * the free area is the block size. Otherwise, it is the
- * nth (ino[ino[0]]) entry's offset.
- */
-
-static int
-fitpair(pag, need)
-char *pag;
-int need;
-{
- register int n;
- register int off;
- register int free;
- register short *ino = (short *) pag;
-
- off = ((n = GET_SHORT(ino,0)) > 0) ? GET_SHORT(ino,n) : PBLKSIZ;
- free = off - (n + 1) * sizeof(short);
- need += 2 * sizeof(short);
-
- debug(("free %d need %d\n", free, need));
-
- return need <= free;
-}
-
-static void
-putpair(pag, key, val)
-char *pag;
-datum key;
-datum val;
-{
- register int n;
- register int off;
- register short *ino = (short *) pag;
-
- off = ((n = GET_SHORT(ino,0)) > 0) ? GET_SHORT(ino,n) : PBLKSIZ;
-/*
- * enter the key first
- */
- off -= key.dsize;
- if (key.dsize)
- (void) memcpy(pag + off, key.dptr, key.dsize);
- PUT_SHORT(ino,n + 1,off);
-/*
- * now the data
- */
- off -= val.dsize;
- if (val.dsize)
- (void) memcpy(pag + off, val.dptr, val.dsize);
- PUT_SHORT(ino,n + 2,off);
-/*
- * adjust item count
- */
- PUT_SHORT(ino,0,GET_SHORT(ino,0) + 2);
-}
-
-static datum
-getpair(pag, key)
-char *pag;
-datum key;
-{
- register int i;
- register int n;
- datum val;
- register short *ino = (short *) pag;
-
- if ((n = GET_SHORT(ino,0)) == 0)
- return nullitem;
-
- if ((i = seepair(pag, n, key.dptr, key.dsize)) == 0)
- return nullitem;
-
- val.dptr = pag + GET_SHORT(ino,i + 1);
- val.dsize = GET_SHORT(ino,i) - GET_SHORT(ino,i + 1);
- return val;
-}
-
-#ifdef SEEDUPS
-static int
-duppair(pag, key)
-char *pag;
-datum key;
-{
- register short *ino = (short *) pag;
- return GET_SHORT(ino,0) > 0 &&
- seepair(pag, GET_SHORT(ino,0), key.dptr, key.dsize) > 0;
-}
-#endif
-
-static datum
-getnkey(pag, num)
-char *pag;
-int num;
-{
- datum key;
- register int off;
- register short *ino = (short *) pag;
-
- num = num * 2 - 1;
- if (GET_SHORT(ino,0) == 0 || num > GET_SHORT(ino,0))
- return nullitem;
-
- off = (num > 1) ? GET_SHORT(ino,num - 1) : PBLKSIZ;
-
- key.dptr = pag + GET_SHORT(ino,num);
- key.dsize = off - GET_SHORT(ino,num);
-
- return key;
-}
-
-static int
-delpair(pag, key)
-char *pag;
-datum key;
-{
- register int n;
- register int i;
- register short *ino = (short *) pag;
-
- if ((n = GET_SHORT(ino,0)) == 0)
- return 0;
-
- if ((i = seepair(pag, n, key.dptr, key.dsize)) == 0)
- return 0;
-/*
- * found the key. if it is the last entry
- * [i.e. i == n - 1] we just adjust the entry count.
- * hard case: move all data down onto the deleted pair,
- * shift offsets onto deleted offsets, and adjust them.
- * [note: 0 < i < n]
- */
- if (i < n - 1) {
- register int m;
- register char *dst = pag + (i == 1 ? PBLKSIZ : GET_SHORT(ino,i - 1));
- register char *src = pag + GET_SHORT(ino,i + 1);
- register int zoo = dst - src;
-
- debug(("free-up %d ", zoo));
-/*
- * shift data/keys down
- */
- m = GET_SHORT(ino,i + 1) - GET_SHORT(ino,n);
-#ifdef DUFF
-#define MOVB *--dst = *--src
-
- if (m > 0) {
- register int loop = (m + 8 - 1) >> 3;
-
- switch (m & (8 - 1)) {
- case 0: do {
- MOVB; case 7: MOVB;
- case 6: MOVB; case 5: MOVB;
- case 4: MOVB; case 3: MOVB;
- case 2: MOVB; case 1: MOVB;
- } while (--loop);
- }
- }
-#else
-#ifdef MEMMOVE
- memmove(dst, src, m);
-#else
- while (m--)
- *--dst = *--src;
-#endif
-#endif
-/*
- * adjust offset index up
- */
- while (i < n - 1) {
- PUT_SHORT(ino,i, GET_SHORT(ino,i + 2) + zoo);
- i++;
- }
- }
- PUT_SHORT(ino, 0, GET_SHORT(ino, 0) - 2);
- return 1;
-}
-
-/*
- * search for the key in the page.
- * return offset index in the range 0 < i < n.
- * return 0 if not found.
- */
-static int
-seepair(pag, n, key, siz)
-char *pag;
-register int n;
-register char *key;
-register int siz;
-{
- register int i;
- register int off = PBLKSIZ;
- register short *ino = (short *) pag;
-
- for (i = 1; i < n; i += 2) {
- if (siz == off - GET_SHORT(ino,i) &&
- memcmp(key, pag + GET_SHORT(ino,i), siz) == 0)
- return i;
- off = GET_SHORT(ino,i + 1);
- }
- return 0;
-}
-
-static void
-splpage(pag, new, sbit)
-char *pag;
-char *new;
-long sbit;
-{
- datum key;
- datum val;
-
- register int n;
- register int off = PBLKSIZ;
- char cur[PBLKSIZ];
- register short *ino = (short *) cur;
-
- (void) memcpy(cur, pag, PBLKSIZ);
- (void) memset(pag, 0, PBLKSIZ);
- (void) memset(new, 0, PBLKSIZ);
-
- n = GET_SHORT(ino,0);
- for (ino++; n > 0; ino += 2) {
- key.dptr = cur + GET_SHORT(ino,0);
- key.dsize = off - GET_SHORT(ino,0);
- val.dptr = cur + GET_SHORT(ino,1);
- val.dsize = GET_SHORT(ino,0) - GET_SHORT(ino,1);
-/*
- * select the page pointer (by looking at sbit) and insert
- */
- (void) putpair((exhash(key) & sbit) ? new : pag, key, val);
-
- off = GET_SHORT(ino,1);
- n -= 2;
- }
-
- debug(("%d split %d/%d\n", ((short *) cur)[0] / 2,
- ((short *) new)[0] / 2,
- ((short *) pag)[0] / 2));
-}
-
-/*
- * check page sanity:
- * number of entries should be something
- * reasonable, and all offsets in the index should be in order.
- * this could be made more rigorous.
- */
-static int
-chkpage(pag)
-char *pag;
-{
- register int n;
- register int off;
- register short *ino = (short *) pag;
-
- if ((n = GET_SHORT(ino,0)) < 0 || n > PBLKSIZ / sizeof(short))
- return 0;
-
- if (n > 0) {
- off = PBLKSIZ;
- for (ino++; n > 0; ino += 2) {
- if (GET_SHORT(ino,0) > off || GET_SHORT(ino,1) > off ||
- GET_SHORT(ino,1) > GET_SHORT(ino,0))
- return 0;
- off = GET_SHORT(ino,1);
- n -= 2;
- }
- }
- return 1;
-}
-
-/* hash.c */
-/*
- * sdbm - ndbm work-alike hashed database library
- * based on Per-Aake Larson's Dynamic Hashing algorithms. BIT 18 (1978).
- * author: oz@nexus.yorku.ca
- * status: public domain. keep it that way.
- *
- * hashing routine
- */
-
-/*
- * polynomial conversion ignoring overflows
- * [this seems to work remarkably well, in fact better
- * then the ndbm hash function. Replace at your own risk]
- * use: 65599 nice.
- * 65587 even better.
- */
-long
-dbm_hash(str, len)
-register char *str;
-register int len;
-{
- register unsigned long n = 0;
-
-#ifdef DUFF
-
-#define HASHC n = *str++ + 65599 * n
-
- if (len > 0) {
- register int loop = (len + 8 - 1) >> 3;
-
- switch(len & (8 - 1)) {
- case 0: do {
- HASHC; case 7: HASHC;
- case 6: HASHC; case 5: HASHC;
- case 4: HASHC; case 3: HASHC;
- case 2: HASHC; case 1: HASHC;
- } while (--loop);
- }
-
- }
-#else
- while (len--)
- n = ((*str++) & 255) + 65587L * n;
-#endif
- return n;
-}