More robust example of numeric argument handling. The old example

code would dereference NULL for mixed letter and number args.
OK deraadt@

1 files changed, 23 insertions, 11 deletions

diff --git a/src/lib/libc/stdlib/getopt.3 b/src/lib/libc/stdlib/getopt.3
index e0dc3701f9..52c902d6a5 100644
--- a/src/lib/libc/stdlib/getopt.3
+++ b/src/lib/libc/stdlib/getopt.3
@@ -25,7 +25,7 @@
 .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 .\" SUCH DAMAGE.
 .\"
-.\"     $OpenBSD: getopt.3,v 1.31 2005/03/26 22:02:15 millert Exp $
+.\"     $OpenBSD: getopt.3,v 1.32 2005/07/01 02:11:55 millert Exp $
 .\"
 .Dd December 17, 2002
 .Dt GETOPT 3
@@ -351,22 +351,34 @@ as an option.
 This practice is wrong, and should not be used in any current development.
 It is provided for backward compatibility
 .Em only .
-The following code fragment works in most cases.
+The following code fragment works in most cases and can handle mixed
+number and letter arguments.
+
 .Bd -literal -offset indent
-int ch;
-long length;
-char *p;
+int aflag = 0, bflag = 0, ch, lastch = '\e0';
+int length = -1, newarg = 1, prevoptind = 1; 
 
-while ((ch = getopt(argc, argv, "0123456789")) != -1) {
+while ((ch = getopt(argc, argv, "0123456789ab")) != -1) {
         switch (ch) {
         case '0': case '1': case '2': case '3': case '4':
         case '5': case '6': case '7': case '8': case '9':
-                p = argv[optind - 1];
-                if (p[0] == '-' && p[1] == ch && !p[2])
-                        length = ch - '0';
-                else
-                        length = strtol(argv[optind] + 1, NULL, 10);
+                if (newarg || !isdigit(lastch))
+                        length = 0;
+                else if (length > INT_MAX / 10)
+                        usage();
+                length = (length * 10) + (ch - '0');                    
+                break;
+        case 'a':
+                aflag = 1;
                 break;
+        case 'b':
+                bflag = 1;
+                break;
+        default:
+                usage();
         }
+        lastch = ch;
+        newarg = optind != prevoptind;
+        prevoptind = optind;                                            
 }
 .Ed