[hackers] [sbase] Check parseoffset return value in od(1) || FRIGN

[git]

commit 81634512496b3188aaf77c71506ed248af132066
Author:     FRIGN <d...@frign.de>
AuthorDate: Wed Sep 30 19:13:32 2015 +0200
Commit:     sin <s...@2f30.org>
CommitDate: Wed Sep 30 19:44:10 2015 +0100

    Check parseoffset return value in od(1)
    
    Yeah, kinda embarassing. Forgot about that.

diff --git a/od.c b/od.c
index 30031c7..f4315ba 100644
--- a/od.c
+++ b/od.c
@@ -118,10 +118,12 @@ main(int argc, char *argv[])
                radix = s[0];
                break;
        case 'j':
-               skip = parseoffset(EARGF(usage()));
+               if ((skip = parseoffset(EARGF(usage()))) < 0)
+                       return 1;
                break;
        case 'N':
-               maxbytes = parseoffset(EARGF(usage()));
+               if ((maxbytes = parseoffset(EARGF(usage()))) < 0)
+                       return 1;
                break;
        case 't':
                s = EARGF(usage());