/* * POSIX standard *	test expression *	[ expression ] */ #include <u.h>#include <libc.h>#define EQ(a,b)	((tmp=a)==0?0:(strcmp(tmp,b)==0)) int	ap;int	ac;char	**av;char	*tmp; void	synbad(char *, char *);int	length(char *);int	fsizep(char *);int	isdir(char *);int	isreg(char *);int	isatty(int);int	isint(char *, int *);int	tio(char *, int);int	e(void), e1(void), e2(void), e3(void); voidmain(int argc, char *argv[]){ 	ac = argc; av = argv; ap = 1;	if(EQ(argv[0],"[")) {		if(!EQ(argv[--ac],"]"))			synbad("] missing","");	}	argv[ac] = 0;	if (ac<=1) exits("usage");	exits(e()?0:"false");} char *nxtarg(int mt){	if(ap>=ac){		if(mt){			ap++;			return(0);		}		synbad("argument expected","");	}	return(av[ap++]);} intnxtintarg(int *pans){	if(ap<ac && isint(av[ap], pans)){		ap++;		return 1;	}	return 0;} inte(void) {	int p1; 	p1 = e1();	if (EQ(nxtarg(1), "-o")) return(p1 | e());	ap--;	return(p1);} inte1(void) {	int p1; 	p1 = e2();	if (EQ(nxtarg(1), "-a")) return (p1 & e1());	ap--;	return(p1);} inte2(void) {	if (EQ(nxtarg(0), "!"))		return(!e3());	ap--;	return(e3());} inte3(void) {	int p1;	char *a;	char *p2;	int int1, int2; 	a = nxtarg(0);	if(EQ(a, "(")) {		p1 = e();		if(!EQ(nxtarg(0), ")")) synbad(") expected","");		return(p1);	} 	if(EQ(a, "-f"))		return(isreg(nxtarg(0))); 	if(EQ(a, "-d"))		return(isdir(nxtarg(0))); 	if(EQ(a, "-r"))		return(tio(nxtarg(0), 4)); 	if(EQ(a, "-w"))		return(tio(nxtarg(0), 2)); 	if(EQ(a, "-x"))		return(tio(nxtarg(0), 1)); 	if(EQ(a, "-e"))		return(tio(nxtarg(0), 0)); 	if(EQ(a, "-c"))		return(0); 	if(EQ(a, "-b"))		return(0); 	if(EQ(a, "-u"))		return(0); 	if(EQ(a, "-g"))		return(0); 	if(EQ(a, "-s"))		return(fsizep(nxtarg(0))); 	if(EQ(a, "-t"))		if(ap>=ac || !nxtintarg(&int1))			return(isatty(1));		else			return(isatty(int1)); 	if(EQ(a, "-n"))		return(!EQ(nxtarg(0), ""));	if(EQ(a, "-z"))		return(EQ(nxtarg(0), "")); 	p2 = nxtarg(1);	if (p2==0)		return(!EQ(a,""));	if(EQ(p2, "="))		return(EQ(nxtarg(0), a)); 	if(EQ(p2, "!="))		return(!EQ(nxtarg(0), a)); 	if(!isint(a, &int1))		return(!EQ(a,"")); 	if(nxtintarg(&int2)){		if(EQ(p2, "-eq"))			return(int1==int2);		if(EQ(p2, "-ne"))			return(int1!=int2);		if(EQ(p2, "-gt"))			return(int1>int2);		if(EQ(p2, "-lt"))			return(int1<int2);		if(EQ(p2, "-ge"))			return(int1>=int2);		if(EQ(p2, "-le"))			return(int1<=int2);	} 	synbad("unknown operator ",p2);	return 0;		/* to shut ken up */} inttio(char *a, int f){	return access (a, f) >= 0;} intisdir(char *f){	Dir dir; 	if(dirstat(f,&dir)<0)		return(0);	return(dir.mode&CHDIR);} intisreg(char *f){	Dir dir; 	if(dirstat(f,&dir)<0)		return(0);	return(!(dir.mode&CHDIR));} intisatty(int fd){	Dir d1, d2; 	if(dirfstat(fd, &d1) < 0)		return 0;	if(dirstat("/dev/cons", &d2) < 0)		return 0;	return d1.type==d2.type && d1.dev==d2.dev && d1.qid.path==d2.qid.path;} intfsizep(char *f){	Dir dir;	if(dirstat(f,&dir)<0)		return(0);	return(dir.length>0);} voidsynbad(char *s1, char *s2){	int len; 	write(2, "test: ", 6);	if ((len = strlen(s1)) != 0)		write(2, s1, len);	if ((len = strlen(s2)) != 0)		write(2, s2, len);	write(2, "\n", 1);	exits("bad syntax");} intlength(char *s){	char *es=s;	while(*es++);	return(es-s-1);} intisint(char *s, int *pans){	char *ep; 	*pans = strtol(s, &ep, 0);	return (*ep == 0);}