Re: patch to add getopt parsing to expr

[Joe Talbott]

On Mon, Jan 19, 2009 at 11:27:18PM -0500, Joe Talbott wrote:
> Here's a patch to add getopt(3) support to expr so that -- is accepted as
> required by POSIX.  This was pointed out by vstemen on IRC.  I'll
> commit sometime after the release if there are no objections.
> 
> Joe

Forgot the patch.

Joe

diff --git a/bin/expr/expr.y b/bin/expr/expr.y
index 0bcd6e0..05564a7 100644
--- a/bin/expr/expr.y
+++ b/bin/expr/expr.y
@@ -18,6 +18,7 @@
 #include <errno.h>
 #include <regex.h>
 #include <limits.h>
+#include <unistd.h>
   
 enum valtype {
        integer, numeric_string, string
@@ -244,12 +245,31 @@ is_zero_or_null(struct val *vp)
        /* NOTREACHED */
 }
 
+static void
+usage(void)
+{
+        fprintf(stderr,
+                "usage: expr <expression>\n");
+        exit(EXIT_FAILURE);
+}
+
 int
-main (int argc __unused, char **argv)
+main (int argc, char **argv)
 {
+       int ch;
        setlocale (LC_ALL, "");
 
-       av = argv + 1;
+       while ((ch = getopt(argc, argv, "-")) != -1) {
+               switch (ch) {
+               default:
+                       usage();
+                       /* NOTREACED */
+               }
+       }
+       argc -= optind;
+       argv += optind;
+
+       av = argv;
 
        yyparse ();