/***************************************************************************** * * $Id$ * Purpose ...............: MBSE BBS Mail Gate * ***************************************************************************** * Copyright (C) 1997-2005 * * Michiel Broek FIDO: 2:280/2802 * Beekmansbos 10 * 1971 BV IJmuiden * the Netherlands * * This file is part of MBSE BBS. * * This BBS is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation; either version 2, or (at your option) any * later version. * * MBSE BBS is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with MBSE BBS; see the file COPYING. If not, write to the Free * Software Foundation, 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. *****************************************************************************/ #include "../config.h" #include "../lib/mbselib.h" #include "lhash.h" /* crypto/lhash/lhash.c */ /* Copyright (C) 1995-1996 Eric Young (eay@mincom.oz.au) * All rights reserved. * * This file is part of an SSL implementation written * by Eric Young (eay@mincom.oz.au). * The implementation was written so as to conform with Netscapes SSL * specification. This library and applications are * FREE FOR COMMERCIAL AND NON-COMMERCIAL USE * as long as the following conditions are aheared to. * * Copyright remains Eric Young's, and as such any Copyright notices in * the code are not to be removed. If this code is used in a product, * Eric Young should be given attribution as the author of the parts used. * This can be in the form of a textual message at program startup or * in documentation (online or textual) provided with the package. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by Eric Young (eay@mincom.oz.au) * * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * The licence and distribution terms for any publically available version or * derivative of this code cannot be changed. i.e. this code cannot simply be * copied and put under another distribution licence * [including the GNU Public Licence.] */ char *lh_version=(char *)"lhash part of SSLeay 0.6.4 30-Aug-1996"; /* Code for dynamic hash table routines * Author - Eric Young v 2.0 * * 2.0 eay - Fixed a bug that occured when using lh_delete * from inside lh_doall(). As entries were deleted, * the 'table' was 'contract()ed', making some entries * jump from the end of the table to the start, there by * skiping the lh_doall() processing. eay - 4/12/95 * * 1.9 eay - Fixed a memory leak in lh_free, the LHASH_NODEs * were not being free()ed. 21/11/95 * * 1.8 eay - Put the stats routines into a seperate file, lh_stats.c * 19/09/95 * * 1.7 eay - Removed the fputs() for realloc failures - the code * should silently tolerate them. I have also fixed things * lint complained about 04/05/95 * * 1.6 eay - Fixed an invalid pointers in contract/expand 27/07/92 * * 1.5 eay - Fixed a misuse of realloc in expand 02/03/1992 * * 1.4 eay - Fixed lh_doall so the function can call lh_delete 28/05/91 * * 1.3 eay - Fixed a few lint problems 19/3/1991 * * 1.2 eay - Fixed lh_doall problem 13/3/1991 * * 1.1 eay - Added lh_doall * * 1.0 eay - First version */ #undef MIN_NODES #define MIN_NODES 16 #define UP_LOAD (2*LH_LOAD_MULT) /* load times 256 (default 2) */ #define DOWN_LOAD (LH_LOAD_MULT) /* load times 256 (default 1) */ #ifndef NOPROTO #define P_CP char * #define P_CPP char *,char * static void expand(LHASH *lh); static void contract(LHASH *lh); static LHASH_NODE **getrn(LHASH *lh, char *data, unsigned int *rhash); #else #define P_CP #define P_CPP static void expand(); static void contract(); static LHASH_NODE **getrn(); #endif LHASH *lh_new(unsigned int (*h)(char *), int (*c)(char *, char *)) { LHASH *ret; int i; if ((ret=(LHASH *)malloc(sizeof(LHASH))) == NULL) goto err0; if ((ret->b=(LHASH_NODE **)malloc(sizeof(LHASH_NODE *)*MIN_NODES)) == NULL) goto err1; for (i=0; i<MIN_NODES; i++) ret->b[i]=NULL; ret->comp=((c == NULL)?(int (*)(char *, char *))strcmp:c); ret->hash=((h == NULL)?(unsigned int (*)(char *))lh_strhash:h); ret->num_nodes=MIN_NODES/2; ret->num_alloc_nodes=MIN_NODES; ret->p=0; ret->pmax=MIN_NODES/2; ret->up_load=UP_LOAD; ret->down_load=DOWN_LOAD; ret->num_items=0; ret->num_expands=0; ret->num_expand_reallocs=0; ret->num_contracts=0; ret->num_contract_reallocs=0; ret->num_hash_calls=0; ret->num_comp_calls=0; ret->num_insert=0; ret->num_replace=0; ret->num_delete=0; ret->num_no_delete=0; ret->num_retreve=0; ret->num_retreve_miss=0; ret->num_hash_comps=0; return(ret); err1: free((char *)ret); err0: return(NULL); } void lh_free(LHASH *lh) { unsigned int i; LHASH_NODE *n,*nn; for (i=0; i<lh->num_nodes; i++) { n=lh->b[i]; while (n != NULL) { nn=n->next; free(n); n=nn; } } free((char *)lh->b); free((char *)lh); } char *lh_insert(LHASH *lh, char *data) { unsigned int hash; LHASH_NODE *nn,**rn; char *ret; if (lh->up_load <= (lh->num_items*LH_LOAD_MULT/lh->num_nodes)) expand(lh); rn=getrn(lh,data,&hash); if (*rn == NULL) { if ((nn=(LHASH_NODE *)malloc(sizeof(LHASH_NODE))) == NULL) return(NULL); nn->data=data; nn->next=NULL; nn->hash=hash; *rn=nn; ret=NULL; lh->num_insert++; lh->num_items++; } else /* replace same key */ { ret= (*rn)->data; (*rn)->data=data; lh->num_replace++; } return(ret); } char *lh_delete(LHASH *lh, char *data) { unsigned int hash; LHASH_NODE *nn,**rn; char *ret; rn=getrn(lh,data,&hash); if (*rn == NULL) { lh->num_no_delete++; return(NULL); } else { nn= *rn; *rn=nn->next; ret=nn->data; free((char *)nn); lh->num_delete++; } lh->num_items--; if ((lh->num_nodes > MIN_NODES) && (lh->down_load >= (lh->num_items*LH_LOAD_MULT/lh->num_nodes))) contract(lh); return(ret); } char *lh_retrieve(LHASH *lh, char *data) { unsigned int hash; LHASH_NODE **rn; char *ret; rn=getrn(lh,data,&hash); if (*rn == NULL) { lh->num_retreve_miss++; return(NULL); } else { ret= (*rn)->data; lh->num_retreve++; } return(ret); } void lh_doall(LHASH *lh, void (*func)(char *, char *)) { lh_doall_arg(lh,func,NULL); } void lh_doall_arg(LHASH *lh, void(*func)(char *, char *), char *arg) { int i; LHASH_NODE *a,*n; /* reverse the order so we search from 'top to bottom' * We were having memory leaks otherwise */ for (i=lh->num_nodes-1; i>=0; i--) { a=lh->b[i]; while (a != NULL) { /* 28/05/91 - eay - n added so items can be deleted * via lh_doall */ n=a->next; func(a->data,arg); a=n; } } } static void expand(LHASH *lh) { LHASH_NODE **n,**n1,**n2,*np; unsigned int p,i,j; unsigned int hash,nni; lh->num_nodes++; lh->num_expands++; p=(int)lh->p++; n1= &(lh->b[p]); n2= &(lh->b[p+(int)lh->pmax]); *n2=NULL; /* 27/07/92 - eay - undefined pointer bug */ nni=lh->num_alloc_nodes; for (np= *n1; np != NULL; ) { hash=np->hash; if ((hash%nni) != p) { /* move it */ *n1= (*n1)->next; np->next= *n2; *n2=np; } else n1= &((*n1)->next); np= *n1; } if ((lh->p) >= lh->pmax) { j=(int)lh->num_alloc_nodes*2; n=(LHASH_NODE **)realloc((char *)lh->b, (unsigned int)sizeof(LHASH_NODE *)*j); if (n == NULL) { WriteError("lhash: realloc error in expand()"); lh->p=0; return; } /* else */ for (i=(int)lh->num_alloc_nodes; i<j; i++)/* 26/02/92 eay */ n[i]=NULL; /* 02/03/92 eay */ lh->pmax=lh->num_alloc_nodes; lh->num_alloc_nodes=j; lh->num_expand_reallocs++; lh->p=0; lh->b=n; } } static void contract(LHASH *lh) { LHASH_NODE **n,*n1,*np; np=lh->b[lh->p+lh->pmax-1]; lh->b[lh->p+lh->pmax-1]=NULL; /* 24/07-92 - eay - weird but :-( */ if (lh->p == 0) { n=(LHASH_NODE **)realloc((char *)lh->b, (unsigned int)(sizeof(LHASH_NODE *)*lh->pmax)); if (n == NULL) { WriteError("lhash: realloc error in contract()"); return; } lh->num_contract_reallocs++; lh->num_alloc_nodes/=2; lh->pmax/=2; lh->p=lh->pmax-1; lh->b=n; } else lh->p--; lh->num_nodes--; lh->num_contracts++; n1=lh->b[(int)lh->p]; if (n1 == NULL) lh->b[(int)lh->p]=np; else { while (n1->next != NULL) n1=n1->next; n1->next=np; } } static LHASH_NODE **getrn(LHASH *lh, char *data, unsigned int *rhash) { LHASH_NODE **ret,*n1; unsigned int hash,nn; int (*cf)(char *, char *); hash=(*(lh->hash))(data); lh->num_hash_calls++; *rhash=hash; nn=hash%lh->pmax; if (nn < lh->p) nn=hash%lh->num_alloc_nodes; cf=lh->comp; ret= &(lh->b[(int)nn]); for (n1= *ret; n1 != NULL; n1=n1->next) { lh->num_hash_comps++; if (n1->hash != hash) { ret= &(n1->next); continue; } lh->num_comp_calls++; if ((*cf)(n1->data,data) == 0) break; ret= &(n1->next); } return(ret); } /* static unsigned long lh_strhash(str) char *str; { int i,l; unsigned long ret=0; unsigned short *s; if (str == NULL) return(0); l=(strlen(str)+1)/2; s=(unsigned short *)str; for (i=0; i<l; i++) ret^=(s[i]<<(i&0x0f)); return(ret); } */ /* The following hash seems to work very well on normal text strings * no collisions on /usr/dict/words and it distributes on %2^n quite * well, not as good as MD5, but still good. */ unsigned int lh_strhash(char *c) { unsigned int ret=0; int n; unsigned int v; int r; if ((c == NULL) || (*c == '\0')) return(ret); /* unsigned char b[16]; MD5(c,strlen(c),b); return(b[0]|(b[1]<<8)|(b[2]<<16)|(b[3]<<24)); */ n=0x100; while (*c) { v=n|(*c); n+=0x100; r= (int)((v>>2)^v)&0x0f; ret=(ret<<r)|(ret>>(32-r)); ret&=0xFFFFFFFFL; ret^=v*v; c++; } return((ret>>16)^ret); }