/* Copyright (C) 1998-2003 XIAO, Gang of Universite de Nice - Sophia Antipolis
*
* This program 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 of the License, or
* (at your option) any later version.
*
* This program 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 this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include "wims.h"
char *relation_type[]={
"sametext","samecase",
"in", "wordof","itemof","lineof","varof","variableof"
};
#define total_relations (sizeof(relation_type)/sizeof(relation_type[0]))
/* Compares two strings. Returns 1 if yes, 0 if no, -1 if error.
* In fact, -1 will occur only if module_error() is modified to
* return instead of abort.
*/
/* TODO: quoted string. */
int compare(char *p, int numeric, int lvl)
{
char *p1, *p2, *pp, *pt;
char *r1, *r2;
int i, l, k, r, neg, gotl;
/* Check global pairs of parentheses */
p2=strip_trailing_spaces(p);
p1=find_word_start(p);
if(lvl==0 && p2-p1>=MAX_LINELEN-1) module_error("parm_too_long");
while(*p1=='(' && *p2==')' && p2==parend(p1)) {
lvl=0; p1=find_word_start(++p1);
do p2--; while(p2>=p1 && myisspace(*p2));
p2[1]=0;
}
gotl=100; r1=r2=p1; r=-1; neg=0;
for(pp=p1; *pp; pp++) {
if(*pp==')') {badpar: module_error("unmatched_parentheses"); return -1;}
if(*pp=='(') {
pp=parend(pp); if(pp==NULL) goto badpar;
continue;
}
if(gotl>3) {
switch(*pp) {
case '<': {
gotl=3; r1=pp; r2=r1+1; r=102; neg=0;
if(*r2=='=') {r2++; r=103; neg=1;}
if(*r2=='>') {
r2++; neg=1;
if(numeric) r=101; else r=0;
}
break;
}
case '>': {
gotl=3; r1=pp; r2=r1+1; r=103; neg=0;
if(*r2=='=') {r2++; r=102; neg=1;}
break;
}
case '=': {
gotl=3; neg=0; r1=pp; r2=r1+1; if(*r2=='=') r2++;
if(numeric) r=101; else r=0;
break;
}
case '!': {
if(pp[1]=='=') {
gotl=3; r1=pp; r2=pp+2; neg=1;
if(numeric) r=101; else r=0;
}
break;
}
}
if(r2>p1) {
if(lvl==2) break;
pp=r2-1; continue;
}
}
if(!myisspace(*pp)) continue;
pp=find_word_start(pp);
if(gotl>3) {
if(pp[0]=='i' && pp[1]=='s') {k=2; neg=0; goto isnot;}
if(pp[0]=='n' && pp[1]=='o' && pp[2]=='t') {k=3; neg=1; goto isnot;}
goto rel;
isnot:
if(strchr("siwlv",pp
[k
])==NULL
) goto rel
; pt=pp; pp+=k; l=0;
for(i=0;i<total_relations;i++) {
if(strncmp(pp
, relation_type
[i
], l
)==0 && ((!myisalnum(pp[l]) && pp[l]!='_') || pp[l]==0)) break;
}
if(i>=total_relations) {pp--; continue;}
gotl=3; r=i+1; pp+=l; r1=pt; r2=pp;
if(lvl==2) break; else {pp--; continue;}
}
rel:
if(*pp!='|' && *pp!='&' && *pp!='a' && *pp!='o')
{pp--; continue;}
if(gotl>2 &&
((myisspace
(pp
[3]) && strncmp(pp
,"and",3)==0) || (myisspace
(pp
[2]) && strncmp(pp
,"&&",2)==0))) { gotl=2; r1=pp; pp=r2=find_word_end(r1);
if(lvl==1) break; else {pp--;continue;}
}
if(gotl>1 && myisspace(pp[2]) &&
gotl=1; r1=pp; r2=pp=r1+2; break;
}
}
if(gotl>20) {
setvar(error_data_string,"relation not defined");
module_error("comp_syntax"); return -1;
}
switch(gotl) {
case 1: { /* or */
*r1=0; i=compare(p1,numeric,1); if(i) return i;
else return compare(r2,numeric,0);
}
case 2: { /* and */
*r1=0; i=compare(p1,numeric,2); if(i<=0) return i;
else return compare(r2,numeric,1);
}
case 3: { /* atomic comparison */
if(r<100) { /* textual comparison */
static char buf1[MAX_LINELEN+1], buf2[MAX_LINELEN+1];
while(r1>p1 && myisspace(r1[-1])) r1--;
memmove(buf1
,p1
,r1
-p1
); buf1
[r1
-p1
]=0; r2=find_word_start(r2);
while(p2>=r2 && myisspace(*p2)) p2--;
memmove(buf2
,r2
,p2
+1-r2
); buf2
[p2
+1-r2
]=0; substitute(buf1); substitute(buf2);
switch(r) {
case 0: { /* equal */
if(strcmp(buf1
,buf2
)==0) return 1^neg
; else return neg
; }
case 1: { /* sametext */
deaccent(buf1); deaccent(buf2);
if(strcasecmp(bufprep(buf1),bufprep(buf2))==0)
return 1^neg;
else return neg;
}
case 2: { /* samecase */
if(strcmp(bufprep
(buf1
),bufprep
(buf2
))==0) return 1^neg;
else return neg;
}
case 3: { /* in */
if(strstr(buf2
,buf1
)!=NULL
) return 1^neg
; else return neg
; }
case 4: { /* wordof */
if(wordchr(buf2,buf1)!=NULL) return 1^neg; else return neg;
}
case 5: { /* itemof */
if(itemchr(buf2,buf1)!=NULL) return 1^neg; else return neg;
}
case 6: { /* lineof */
if(linechr(buf2,buf1)!=NULL) return 1^neg; else return neg;
}
case 7:
case 8: { /* varof */
if(varchr(buf2,buf1)!=NULL) return 1^neg; else return neg;
}
}
}
else { /* numerical comparison */
double d1, d2, sum, diff, prec;
*r1=0;
d1=evalue(p1); d2=evalue(r2);
sum=d1+d2; if(sum<0) sum=-sum;
diff=d1-d2; if(diff<0) diff=-diff;
prec=evalue(getvar("wims_compare_precision")); /* Move string name to header! */
diff=diff*prec;
if(prec>0 && prec<1E10) sum=sum+1/prec;
switch(r) {
case 101: { /* = */
if(sum>=diff) return 1^neg; else return neg;
}
case 102: { /* < */
if(d1<d2) return 1^neg; else return neg;
}
case 103: { /* > */
if(d1>d2) return 1^neg; else return neg;
}
default: break; /* should never occur */
}
}
}
}
internal_error("compare(): this should never happen.");
return -1;
}