/* test - test conditions Author: Erik Baalbergen */ /* Test- version 7-like test(1). * * Grammar: expr ::= bexpr | bexpr "-o" expr ; * bexpr ::= primary | primary "-a" bexpr ; * primary ::= unary-operator operand * | operand binary-operator operand * | operand * | "(" expr ")" * | "!" expr * ; * unary-operator ::= "-r"|"-w"|"-f"|"-d"|"-s"|"-t"|"-z"|"-n"; * binary-operator ::= "="|"!="|"-eq"|"-ne"|"-ge"|"-gt"|"-le"|"-lt"; * operand ::= <any legal UNIX file name> * * Author: Erik Baalbergen erikb@cs.vu.nl * * History: Fix Bert Reuling #571 (03/09/89 FVK) bert@kyber.UUCP * * Add Jeroen van der Pluijm 09/25/89 jeroen@minixug.nluug.nl * Enabled linking to /usr/bin/[ so you cn use structures * like: * if [ -f ./test.c ] * and so on. Also added checking of argv[0] to see if it * is '[' and the last argument if it is ']'. * * Mod Fred van Kempen 09/27/89 waltje@minixug.nluug.nl * Adapted source to MINIX Style Sheet. * * Mod Bruce Evans 09/27/89 evans@ditsyda.oz.au * Allow whitespace in numbers. * Deleted bloat from single use of stdio (fprintf). */ #include <sys/types.h> #include <sys/stat.h> #include <sgtty.h> #define EOI 0 #define FILRD 1 #define FILWR 2 #define FILND 3 #define FILID 4 #define FILGZ 5 #define FILTT 6 #define STZER 7 #define STNZE 8 #define STEQL 9 #define STNEQ 10 #define INTEQ 11 #define INTNE 12 #define INTGE 13 #define INTGT 14 #define INTLE 15 #define INTLT 16 #define UNEGN 17 #define BAND 18 #define BOR 19 #define LPAREN 20 #define RPAREN 21 #define OPERAND 22 #define UNOP 1 #define BINOP 2 #define BUNOP 3 #define BBINOP 4 #define PAREN 5 struct op { char *op_text; short op_num, op_type; } ops[] = { { "-r", FILRD, UNOP }, { "-w", FILWR, UNOP }, { "-f", FILND, UNOP }, { "-d", FILID, UNOP }, { "-s", FILGZ, UNOP }, { "-t", FILTT, UNOP }, { "-z", STZER, UNOP }, { "-n", STNZE, UNOP }, { "=", STEQL, BINOP }, { "!=", STNEQ, BINOP }, { "-eq", INTEQ, BINOP }, { "-ne", INTNE, BINOP }, { "-ge", INTGE, BINOP }, { "-gt", INTGT, BINOP }, { "-le", INTLE, BINOP }, { "-lt", INTLT, BINOP }, { "!", UNEGN, BUNOP }, { "-a", BAND, BBINOP }, { "-o", BOR, BBINOP }, { "(", LPAREN, PAREN }, { ")", RPAREN, PAREN }, { 0, 0, 0 } }; char **ip; char *prog; struct op *ip_op; void syntax() { write(2, prog, strlen(prog)); write(2, ": syntax error\n", 15); exit(1); } long num(s) register char *s; { long l = 0; long sign = 1; while (*s == ' ' || *s == '\t') ++s; if (*s == '\0') syntax(); if (*s == '-') { sign = -1; s++; } while (*s >= '0' && *s <= '9') l = l * 10 + *s++ - '0'; while (*s == ' ' || *s == '\t') ++s; if (*s != '\0') syntax(); return(sign * l); } int filstat(nm, mode) char *nm; int mode; { struct stat s; struct sgttyb t; switch (mode) { case FILRD: return(access(nm, 4) == 0); case FILWR: return(access(nm, 2) == 0); case FILND: return(stat(nm, &s) == 0 && ((s.st_mode & S_IFMT) != S_IFDIR)); case FILID: return(stat(nm, &s) == 0 && ((s.st_mode & S_IFMT) == S_IFDIR)); case FILGZ: return(stat(nm, &s) == 0 && (s.st_size > 0L)); case FILTT: return(ioctl((int) num(nm), TIOCGETP, &t) == 0); } } int lex(s) register char *s; { register struct op *op = ops; if (s == 0) return EOI; while (op->op_text) { if (strcmp(s, op->op_text) == 0) { ip_op = op; return(op->op_num); } op++; } ip_op = (struct op *) 0; return(OPERAND); } int primary(n) int n; { register char *opnd1, *opnd2; int res; if (n == EOI) syntax(); if (n == UNEGN) return (!expr(lex(*++ip))); if (n == LPAREN) { res = expr(lex(*++ip)); if (lex(*++ip) != RPAREN) syntax(); return(res); } if (n == OPERAND) { opnd1 = *ip; (void) lex(*++ip); if (ip_op && ip_op->op_type == BINOP) { struct op *op = ip_op; if ((opnd2 = *++ip) == (char *) 0) syntax(); switch (op->op_num) { case STEQL: return(strcmp(opnd1, opnd2) == 0); case STNEQ: return(strcmp(opnd1, opnd2) != 0); case INTEQ: return(num(opnd1) == num(opnd2)); case INTNE: return(num(opnd1) != num(opnd2)); case INTGE: return(num(opnd1) >= num(opnd2)); case INTGT: return(num(opnd1) > num(opnd2)); case INTLE: return(num(opnd1) <= num(opnd2)); case INTLT: return(num(opnd1) < num(opnd2)); } } ip--; return(strlen(opnd1) > 0); } /* Unary expression */ if (ip_op->op_type != UNOP || *++ip == 0) syntax(); if (n == STZER) return (strlen(*ip) == 0); if (n == STNZE) return (strlen(*ip) != 0); return(filstat(*ip, n)); } int bexpr(n) int n; { int res; if (n == EOI) syntax(); res = primary(n); if (lex(*++ip) == BAND) return(bexpr(lex(*++ip)) && res); ip--; return(res); } int expr(n) int n; { int res; if (n == EOI) syntax(); res = bexpr(n); if (lex(*++ip) == BOR) return(expr(lex(*++ip)) || res); ip--; return(res); } main(argc, argv) int argc; char **argv; { if (argv[0][0] == '[' && argv[argc - 1][0] != ']') { write(2, "test: ] missing\n", 16); exit(1); } if (argv[0][0] == '[') argc--; if (argc == 1) exit(1); prog = argv[0]; ip = &argv[1]; exit(!expr(lex(*ip))); }