/* $RCSfile: hash.c,v $$Revision: 1.1.1.1 $$Date: 1994/09/10 06:27:54 $ * * Copyright (c) 1991, Larry Wall * * You may distribute under the terms of either the GNU General Public * License or the Artistic License, as specified in the README file. * * $Log: hash.c,v $ * Revision 1.1.1.1 1994/09/10 06:27:54 gclarkii * Initial import of Perl 4.046 bmaked * * Revision 1.1.1.1 1993/08/23 21:30:10 nate * PERL! * * Revision 4.0.1.1 91/06/07 12:15:55 lwall * patch4: new copyright notice * * Revision 4.0 91/03/20 01:57:49 lwall * 4.0 baseline. * */ #include #include "EXTERN.h" #include "handy.h" #include "util.h" #include "a2p.h" STR * hfetch(tb,key) register HASH *tb; char *key; { register char *s; register int i; register int hash; register HENT *entry; if (!tb) return Nullstr; for (s=key, i=0, hash = 0; /* while */ *s; s++, i++, hash *= 5) { hash += *s * coeff[i]; } entry = tb->tbl_array[hash & tb->tbl_max]; for (; entry; entry = entry->hent_next) { if (entry->hent_hash != hash) /* strings can't be equal */ continue; if (strNE(entry->hent_key,key)) /* is this it? */ continue; return entry->hent_val; } return Nullstr; } bool hstore(tb,key,val) register HASH *tb; char *key; STR *val; { register char *s; register int i; register int hash; register HENT *entry; register HENT **oentry; if (!tb) return FALSE; for (s=key, i=0, hash = 0; /* while */ *s; s++, i++, hash *= 5) { hash += *s * coeff[i]; } oentry = &(tb->tbl_array[hash & tb->tbl_max]); i = 1; for (entry = *oentry; entry; i=0, entry = entry->hent_next) { if (entry->hent_hash != hash) /* strings can't be equal */ continue; if (strNE(entry->hent_key,key)) /* is this it? */ continue; /*NOSTRICT*/ safefree((char*)entry->hent_val); entry->hent_val = val; return TRUE; } /*NOSTRICT*/ entry = (HENT*) safemalloc(sizeof(HENT)); entry->hent_key = savestr(key); entry->hent_val = val; entry->hent_hash = hash; entry->hent_next = *oentry; *oentry = entry; if (i) { /* initial entry? */ tb->tbl_fill++; if ((tb->tbl_fill * 100 / (tb->tbl_max + 1)) > FILLPCT) hsplit(tb); } return FALSE; } #ifdef NOTUSED bool hdelete(tb,key) register HASH *tb; char *key; { register char *s; register int i; register int hash; register HENT *entry; register HENT **oentry; if (!tb) return FALSE; for (s=key, i=0, hash = 0; /* while */ *s; s++, i++, hash *= 5) { hash += *s * coeff[i]; } oentry = &(tb->tbl_array[hash & tb->tbl_max]); entry = *oentry; i = 1; for (; entry; i=0, oentry = &entry->hent_next, entry = entry->hent_next) { if (entry->hent_hash != hash) /* strings can't be equal */ continue; if (strNE(entry->hent_key,key)) /* is this it? */ continue; safefree((char*)entry->hent_val); safefree(entry->hent_key); *oentry = entry->hent_next; safefree((char*)entry); if (i) tb->tbl_fill--; return TRUE; } return FALSE; } #endif hsplit(tb) HASH *tb; { int oldsize = tb->tbl_max + 1; register int newsize = oldsize * 2; register int i; register HENT **a; register HENT **b; register HENT *entry; register HENT **oentry; a = (HENT**) saferealloc((char*)tb->tbl_array, newsize * sizeof(HENT*)); bzero((char*)&a[oldsize], oldsize * sizeof(HENT*)); /* zero second half */ tb->tbl_max = --newsize; tb->tbl_array = a; for (i=0; ihent_hash & newsize) != i) { *oentry = entry->hent_next; entry->hent_next = *b; if (!*b) tb->tbl_fill++; *b = entry; continue; } else oentry = &entry->hent_next; } if (!*a) /* everything moved */ tb->tbl_fill--; } } HASH * hnew() { register HASH *tb = (HASH*)safemalloc(sizeof(HASH)); tb->tbl_array = (HENT**) safemalloc(8 * sizeof(HENT*)); tb->tbl_fill = 0; tb->tbl_max = 7; hiterinit(tb); /* so each() will start off right */ bzero((char*)tb->tbl_array, 8 * sizeof(HENT*)); return tb; } #ifdef NOTUSED hshow(tb) register HASH *tb; { fprintf(stderr,"%5d %4d (%2d%%)\n", tb->tbl_max+1, tb->tbl_fill, tb->tbl_fill * 100 / (tb->tbl_max+1)); } #endif hiterinit(tb) register HASH *tb; { tb->tbl_riter = -1; tb->tbl_eiter = Null(HENT*); return tb->tbl_fill; } HENT * hiternext(tb) register HASH *tb; { register HENT *entry; entry = tb->tbl_eiter; do { if (entry) entry = entry->hent_next; if (!entry) { tb->tbl_riter++; if (tb->tbl_riter > tb->tbl_max) { tb->tbl_riter = -1; break; } entry = tb->tbl_array[tb->tbl_riter]; } } while (!entry); tb->tbl_eiter = entry; return entry; } char * hiterkey(entry) register HENT *entry; { return entry->hent_key; } STR * hiterval(entry) register HENT *entry; { return entry->hent_val; }