wmii/libregexp/regsub.c

64 lines
1.1 KiB
C
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#include "plan9.h"
#include "regexp9.h"
/* substitute into one string using the matches from the last regexec() */
extern void
regsub(char *sp, /* source string */
char *dp, /* destination string */
int dlen,
Resub *mp, /* subexpression elements */
int ms) /* number of elements pointed to by mp */
{
char *ssp, *ep;
int i;
ep = dp+dlen-1;
while(*sp != '\0'){
if(*sp == '\\'){
switch(*++sp){
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
i = *sp-'0';
if(mp[i].s.sp != 0 && mp!=0 && ms>i)
for(ssp = mp[i].s.sp;
ssp < mp[i].e.ep;
ssp++)
if(dp < ep)
*dp++ = *ssp;
break;
case '\\':
if(dp < ep)
*dp++ = '\\';
break;
case '\0':
sp--;
break;
default:
if(dp < ep)
*dp++ = *sp;
break;
}
}else if(*sp == '&'){
if(mp[0].s.sp != 0 && mp!=0 && ms>0)
if(mp[0].s.sp != 0)
for(ssp = mp[0].s.sp;
ssp < mp[0].e.ep; ssp++)
if(dp < ep)
*dp++ = *ssp;
}else{
if(dp < ep)
*dp++ = *sp;
}
sp++;
}
*dp = '\0';
}