/*  * This file is part of the UCB release of Plan 9. It is subject to the license * terms in the LICENSE file found in the top-level directory of this * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No * part of the UCB release of Plan 9, including this file, may be copied, * modified, propagated, or distributed except according to the terms contained * in the LICENSE file. */ #include <u.h>#include <libc.h>#include "regexp.h" /* substitute into one string using the matches from the last regexec() */extern	voidregsub(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!=0 && mp[i].sp != 0 && ms>i)					for(ssp = mp[i].sp;					     ssp < mp[i].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 && mp[0].sp != 0 && ms>0)				for(ssp = mp[0].sp;				     ssp < mp[0].ep; ssp++)					if(dp < ep)						*dp++ = *ssp;		}else{			if(dp < ep)				*dp++ = *sp;		}		sp++;	}	*dp = '\0';}