X-Git-Url: https://git.saurik.com/apple/shell_cmds.git/blobdiff_plain/2ac7f7944aa87a432c2735764a2da6bb88d37197..ddb4a88b2f582f98073e02a797c5299d71d9527e:/expr/expr.c

diff --git a/expr/expr.c b/expr/expr.c
index 4732044..590608c 100644
--- a/expr/expr.c
+++ b/expr/expr.c
@@ -41,6 +41,7 @@ void free_value __P((struct val *));
 int is_integer __P((struct val *, int64_t *));
 int to_integer __P((struct val *));
 void to_string __P((struct val *));
+int is_null __P((struct val *));
 int is_zero_or_null __P((struct val *));
 void nexttoken __P((void));
 void error __P((void)) __attribute__((__noreturn__));
@@ -118,8 +119,14 @@ is_integer(vp, r)
 	i = 0;
 
 	neg = (*s == '-');
-	if (neg)
+	if (neg) {
 		s++;
+		/* the optional unary minus *must* be followed by digits to 
+		 * be considered an integer.  A '-' alone is not an integer.
+		 */
+		if(!*s)
+			return 0;
+	}
 
 	while (*s) {
 		if (!isdigit(*s))
@@ -179,6 +186,14 @@ to_string(vp)
 	vp->u.s = tmp;
 }
 
+int is_null(vp)
+	struct val     *vp;
+{
+	if ((vp->type != integer) && (*vp->u.s == 0))
+		return 1;
+	return 0;
+}
+
 int
 is_zero_or_null(vp)
 	struct val     *vp;
@@ -239,7 +254,7 @@ error()
 struct val *
 eval6()
 {
-	struct val     *v;
+	struct val *v;
 
 	if (token == OPERAND) {
 		nexttoken();
@@ -250,11 +265,73 @@ eval6()
 		v = eval0();
 
 		if (token != LP)
-			error();
+         		error();
+		  
 		nexttoken();
 		return v;
 	} else {
-		error();
+	   
+		switch (token) {
+	   	case DIV:
+			 nexttoken();
+		   	 tokval = make_str("/");
+		   	 break;
+	   	case MUL: 
+			 nexttoken();
+		    	 tokval = make_str("*");
+		   	 break;
+	   	case OR: 
+		   	 nexttoken();
+		   	 tokval = make_str("|");
+		   	 break;
+	   	case AND: 
+		   	 nexttoken();
+		   	 tokval = make_str("&");
+		   	 break;
+	   	case EQ: 
+		   	 nexttoken();
+		  	 tokval = make_str("=");
+		 	 break;
+	   	case LT: 
+		  	 nexttoken();
+		  	 tokval = make_str("<");
+		  	 break;
+	   	case GT: 
+		  	 nexttoken();
+		  	 tokval = make_str(">");
+		  	 break;
+	   	case ADD: 
+		  	 nexttoken();
+		  	 tokval = make_str("+");
+		  	 break;
+	   	case SUB: 
+		    	 nexttoken();
+		  	 tokval = make_str("-");
+		  	 break;
+	   	case MOD: 
+		   	 nexttoken();
+		  	 tokval = make_str("%");
+		  	 break;
+	   	case NE: 
+		  	 nexttoken();
+		  	 tokval = make_str("!=");
+		  	 break;
+	   	case LE: 
+		  	 nexttoken();
+		  	 tokval = make_str("<=");
+		  	 break;
+	   	case MATCH:
+		  	 nexttoken();
+		  	 tokval = make_str(":");
+		  	 break;
+	   	case GE: 
+		  	 nexttoken();
+		  	 tokval = make_str(">=");
+		  	 break;
+	   	case EOI:
+		  	 error();
+		}
+        	return tokval;
 	}
 	/* NOTREACHED */
 }
@@ -513,6 +590,10 @@ eval0()
 		if (is_zero_or_null(l)) {
 			free_value(l);
 			l = r;
+			if( is_null(r) ) {
+				free_value(r);
+				l = make_int(0);
+			}
 		} else {
 			free_value(r);
 		}
@@ -531,13 +612,15 @@ main(argc, argv)
 
 	(void) setlocale(LC_ALL, "");
 	av = argv + 1;
-
+	if (*av && !strcmp(*av, "--"))
+	    av++;
 	nexttoken();
 	vp = eval0();
 
 	if (token != EOI)
 		error();
-
+        if (vp->type == string && vp->u.s[0]) 
+		to_integer(vp);		/* -0 is not a string */
 	if (vp->type == integer)
 		(void)printf("%lld\n", vp->u.i);
 	else