#include "rc.h"#include "y.tab.h" #define	NTOK	8192 int getnext(void); int	future=EOF;int	doprompt=1;int	inquote;int	nerror;char	*promptstr; char	tok[NTOK]; int	lastdol;	/* was the last token read '$' or '$#' or '"'? */int	lastword;	/* was the last token read a word or compound word terminator? */int	lastc; voidkinit(void){	kenter(FOR, "for");	kenter(IN, "in");	kenter(WHILE, "while");	kenter(IF, "if");	kenter(NOT, "not");	kenter(TWIDDLE, "~");	kenter(BANG, "!");	kenter(SUBSHELL, "@");	kenter(SWITCH, "switch");	kenter(FN, "fn");} intwordchr(int c){	return !strchr("\n \t\r#;&|^$=`'{}()<>", c) && c!=EOF;} intidchr(int c){	/*	 * Formerly:	 * return 'a'<=c && c<='z' || 'A'<=c && c<='Z' || '0'<=c && c<='9'	 *	|| c=='_' || c=='*';	 */	return c>' ' && !strchr("!\"#$%&'()+,-./:;<=>?@[\\]^`{|}~", c);} /* * Look ahead in the input stream */intnextc(void){	if(future==EOF)		future=getnext();	return future;} /* * Consume the lookahead character. */intadvance(void){	int c=nextc();	lastc=future;	future=EOF;	return c;} /* * read a character from the input stream */	intgetnext(void){	register int c;	static peekc=EOF;	if(peekc!=EOF){		c=peekc;		peekc=EOF;		return c;	}	if(runq->eof) return EOF;	if(doprompt)		pprompt();	c=rchr(runq->cmdfd);	if(!inquote && c=='\\'){		c=rchr(runq->cmdfd);		if(c=='\n'){			doprompt=1;			c=' ';		}		else{			peekc=c;			c='\\';		}	}	doprompt=doprompt || c=='\n' || c==EOF;	if(c==EOF) runq->eof++;	else if(flag['V'] || ndot>=2 && flag['v'])		pchr(err, c);	return c;} voidpprompt(void){	Var *prompt; 	if(runq->iflag){		pstr(err, promptstr);		flush(err);		prompt=vlook("prompt");		if(prompt->val && prompt->val->next)			promptstr=prompt->val->next->word;		else			promptstr="\t";	}	runq->lineno++;	doprompt=0;} voidskipwhite(void){	int c;	for(;;){		c=nextc();		if(c=='#'){	/* Why did this used to be  if(!inquote && c=='#') ?? */			for(;;){				c=nextc();				if(c=='\n' || c==EOF) break;				advance();			}		}		if(c==' ' || c=='\t' || c=='\r') advance();		else return;	}} voidskipnl(void){	int c;	for(;;){		skipwhite();		c=nextc();		if(c!='\n') return;		advance();	}} intnextis(int c){	if(nextc()==c){		advance();		return 1;	}	return 0;} char *addtok(char *p, int val){	if(p==0) return 0;	if(p==&tok[NTOK]){		*p=0;		yyerror("token buffer too short");		return 0;	}	*p++=val;	return p;} char *addutf(char *p, int c){	p=addtok(p, c);	if(twobyte(c))	 /* 2-byte escape */		return addtok(p, advance());	if(threebyte(c)){	/* 3-byte escape */		p=addtok(p, advance());		return addtok(p, advance());	}	return p;} intyylex(void){	int c, d=nextc();	char *w=tok;	Tree *t; 	yylval.tree=0;	/*	 * Embarassing sneakiness:  if the last token read was a quoted or unquoted	 * WORD then we alter the meaning of what follows.  If the next character	 * is `(', we return SUB (a subscript paren) and consume the `('.  Otherwise,	 * if the next character is the first character of a simple or compound word,	 * we insert a `^' before it.	 */	if(lastword){		lastword=0;		if(d=='('){			advance();			strcpy(tok, "( [SUB]");			return SUB;		}		if(wordchr(d) || d=='\'' || d=='`' || d=='$' || d=='"'){			strcpy(tok, "^");			return '^';		}	}	inquote=0;	skipwhite();	switch(c=advance()){	case EOF:		lastdol=0;		strcpy(tok, "EOF");		return EOF;	case '$':		lastdol=1;		if(nextis('#')){			strcpy(tok, "$#");			return COUNT;		}		if(nextis('"')){			strcpy(tok, "$\"");			return '"';		}		strcpy(tok, "$");		return '$';	case '&':		lastdol=0;		if(nextis('&')){			skipnl();			strcpy(tok, "&&");			return ANDAND;		}		strcpy(tok, "&");		return '&';	case '|':		lastdol=0;		if(nextis(c)){			skipnl();			strcpy(tok, "||");			return OROR;		}	case '<':	case '>':		lastdol=0;		/*		 * funny redirection tokens:		 *	redir:	arrow | arrow '[' fd ']'		 *	arrow:	'<' | '<<' | '>' | '>>' | '|'		 *	fd:	digit | digit '=' | digit '=' digit		 *	digit:	'0'|'1'|'2'|'3'|'4'|'5'|'6'|'7'|'8'|'9'		 * some possibilities are nonsensical and get a message.		 */		*w++=c;		t=newtree();		switch(c){		case '|':			t->type=PIPE;			t->fd0=1;			t->fd1=0;			break;		case '>':			t->type=REDIR;			if(nextis(c)){				t->rtype=APPEND;				*w++=c;			}			else t->rtype=WRITE;			t->fd0=1;			break;		case '<':			t->type=REDIR;			if(nextis(c)){				t->rtype=HERE;				*w++=c;			}			else t->rtype=READ;			t->fd0=0;			break;		}		if(nextis('[')){			*w++='[';			c=advance();			*w++=c;			if(c<'0' || '9'<c){			RedirErr:				*w=0;				yyerror(t->type==PIPE?"pipe syntax"						:"redirection syntax");				return EOF;			}			t->fd0=0;			do{				t->fd0=t->fd0*10+c-'0';				*w++=c;				c=advance();			}while('0'<=c && c<='9');			if(c=='='){				*w++='=';				if(t->type==REDIR)					t->type=DUP;				c=advance();				if('0'<=c && c<='9'){					t->rtype=DUPFD;					t->fd1=t->fd0;					t->fd0=0;					do{						t->fd0=t->fd0*10+c-'0';						*w++=c;						c=advance();					}while('0'<=c && c<='9');				}				else{					if(t->type==PIPE) goto RedirErr;					t->rtype=CLOSE;				}			}			if(c!=']' || t->type==DUP && (t->rtype==HERE || t->rtype==APPEND))				goto RedirErr;			*w++=']';		}		*w='\0';		yylval.tree=t;		if(t->type==PIPE) skipnl();		return t->type;	case '\'':		lastdol=0;		lastword=1;		inquote=1;		for(;;){			c=advance();			if(c==EOF) break;			if(c=='\''){				if(nextc()!='\'')					break;				advance();			}			w=addutf(w, c);		}		if(w!=0) *w='\0';		t=token(tok, WORD);		t->quoted=1;		yylval.tree=t;		return t->type;	}	if(!wordchr(c)){		lastdol=0;		tok[0]=c;		tok[1]='\0';		return c;	}	for(;;){		/* next line should have (char)c==GLOB, but ken's compiler is broken */		if(c=='*' || c=='[' || c=='?' || c==(unsigned char)GLOB)			w=addtok(w, GLOB);		w=addutf(w, c);		c=nextc();		if(lastdol?!idchr(c):!wordchr(c)) break;		advance();	}Out:	lastword=1;	lastdol=0;	if(w!=0) *w='\0';	t=klook(tok);	if(t->type!=WORD) lastword=0;	t->quoted=0;	yylval.tree=t;	return t->type;} void yyerror(char *m){	pfmt(err, "rc: ");	if(runq->cmdfile) pfmt(err, "file %s: ", runq->cmdfile);	if(!runq->iflag) pfmt(err, "line %d: ", runq->lineno);	if(tok[0] && tok[0]!='\n') pfmt(err, "token %q: ", tok);	pfmt(err, "%s\n", m);	flush(err);	lastword=0;	lastdol=0;	while(lastc!='\n' && lastc!=EOF) advance();	nerror++;}