#include	"mk.h" char	*termchars = "\"'= \t";	/*used in parse.c to isolate assignment attribute*/char	*shflags = 0;int	IWS = ' ';		/* inter-word separator in env */ /* *	This file contains functions that depend on the shell's syntax.  Most *	of the routines extract strings observing the shell's escape conventions. */  /* *	skip a token in quotes. */static char *squote(char *cp, int c){	Rune r;	int n; 	while(*cp){		n = chartorune(&r, cp);		if(r == c)			return cp;		if(r == '\\')			n += chartorune(&r, cp+n);		cp += n;	}	SYNERR(-1);		/* should never occur */	fprint(2, "missing closing '\n");	return 0;}/* *	search a string for unescaped characters in a pattern set */char *charin(char *cp, char *pat){	Rune r;	int n, vargen; 	vargen = 0;	while(*cp){		n = chartorune(&r, cp);		switch(r){		case '\\':			/* skip escaped char */			cp += n;			n = chartorune(&r, cp);			break;		case '\'':			/* skip quoted string */		case '"':			cp = squote(cp+1, r);	/* n must = 1 */			if(!cp)				return 0;			break;		case '$':			if(*(cp+1) == '{')				vargen = 1;			break;		case '}':			if(vargen)				vargen = 0;			else if(utfrune(pat, r))				return cp;			break;		default:			if(vargen == 0 && utfrune(pat, r))				return cp;			break;		}		cp += n;	}	if(vargen){		SYNERR(-1);		fprint(2, "missing closing } in pattern generator\n");	}	return 0;} /* *	extract an escaped token.  Possible escape chars are single-quote, *	double-quote,and backslash. */char*expandquote(char *s, Rune esc, Bufblock *b){	Rune r; 	if (esc == '\\') {		s += chartorune(&r, s);		rinsert(b, r);		return s;	} 	while(*s){		s += chartorune(&r, s);		if(r == esc)			return s;		if (r == '\\') {			rinsert(b, r);			s += chartorune(&r, s);		}		rinsert(b, r);	}	return 0;} /* *	Input an escaped token.  Possible escape chars are single-quote, *	double-quote and backslash. */intescapetoken(Biobuf *bp, Bufblock *buf, int preserve, int esc){	int c, line; 	if(esc == '\\') {		c = Bgetrune(bp);		if(c == '\r')			c = Bgetrune(bp);		if (c == '\n')			mkinline++;		rinsert(buf, c);		return 1;	} 	line = mkinline;	while((c = nextrune(bp, 0)) >= 0){		if(c == esc){			if(preserve)				rinsert(buf, c);			return 1;		}		if(c == '\\') {			rinsert(buf, c);			c = Bgetrune(bp);			if(c == '\r')				c = Bgetrune(bp);			if (c < 0)				break;			if (c == '\n')				mkinline++;		}		rinsert(buf, c);	}	SYNERR(line); fprint(2, "missing closing %c\n", esc);	return 0;} /* *	copy a quoted string; s points to char after opening quote */static char *copysingle(char *s, Rune q, Bufblock *buf){	Rune r; 	while(*s){		s += chartorune(&r, s);		rinsert(buf, r);		if(r == q)			break;	}	return s;}/* *	check for quoted strings.  backquotes are handled here; single quotes above. *	s points to char after opening quote, q. */char *copyq(char *s, Rune q, Bufblock *buf){	if(q == '\'' || q == '"')		/* copy quoted string */		return copysingle(s, q, buf); 	if(q != '`')				/* not quoted */		return s; 	while(*s){				/* copy backquoted string */		s += chartorune(&q, s);		rinsert(buf, q);		if(q == '`')			break;		if(q == '\'' || q == '"')			s = copysingle(s, q, buf);	/* copy quoted string */	}	return s;}