Bug in vis(1)

[phillbush]

The following command makes vis(1) go through an infinite loop.

$ printf 'a\tb' | vis -F8

I discovered it while looking through the code.

I am new to C and I was looking the code in order to learn C. I think I got a solution, I have to test it more, though.

int
foldit(char *chunk, int col, int max)
{
    char *cp;
    int newcol;

    /*
     * Keep track of column position. Insert hidden newline
     * if this chunk puts us over the limit.
     */
    newcol = 0;
    for (cp = chunk; *cp; cp++) {
        switch(*cp) {
        case '\n':
        case '\r':
            newcol = col = 0;
            break;
        case '\t':
            col = (col + 8) & ~07;
            newcol = (newcol + 8) & ~07;
            break;
        case '\b':
            col = col ? col - 1 : 0;
            newcol = newcol ? newcol - 1 : 0;
            break;
        default:
            col++;
            newcol++;
        }
    }

    if (col > (max - 2)) {
        printf("\\\n");
        col = newcol;
    } 

    return (col);
}

[ibara]

Hello. This should be reported to bugs@openbsd.org with an inline diff generated from

cvs diff

[CiotBSD]

`cvs diff -u` instead, no?!

Please, read the page "report":
https://www.openbsd.org/report.html

[jggimi]

It should not be necessary, unless the user running cvs was created prior to release 5.4. Since that release, there is an /etc/skel/.cvsrc file which is added to newly created users' $HOME directory, which currently contains:

# $OpenBSD: dot.cvsrc,v 1.3 2016/10/31 20:50:11 tb Exp $
#
diff -uNp
update -Pd
checkout -P
rdiff -u