[MINC-development] bug in upet2mnc

[jcupitt at gmail.com]

Hi, I think I've found a bug in upet2mnc.

If i run the version that comes with Ubuntu Lucid (2.0.18) on an x64
machine, I get:

$ upet2mnc c4.img poop.mnc
Starting conversion
- Input header: c4.img.hdr
- Input image:  c4.img
- Output file:  poop.mnc
WARNING: Unrecognized keyword manufacturer
Segmentation fault
$

Looking at the source, the problem is in the message() function. It
includes this code:

    va_start(ap, fmt);
    if (_verbose_flag || level != MSG_INFO) {
        if (level != MSG_INFO) {
            if (prefix_str != NULL) {
                fprintf(stderr, "%s", prefix_str);
            }
            vfprintf(stderr, fmt, ap);
        }
        if (prefix_str != NULL) {
            fprintf(stdout, "%s", prefix_str);
        }
        vfprintf(stdout, fmt, ap);
    }
    va_end(ap);

So it's setting up ap once but then, for non-info messages, using it
twice. One simple fix would be to put the va_start() around each
vfprintf():

    if (_verbose_flag || level != MSG_INFO) {
        if (level != MSG_INFO) {
            if (prefix_str != NULL) {
                fprintf(stderr, "%s", prefix_str);
            }
            va_start(ap, fmt);
            vfprintf(stderr, fmt, ap);
            va_end(ap);
        }
        if (prefix_str != NULL) {
            fprintf(stdout, "%s", prefix_str);
        }
        va_start(ap, fmt);
        vfprintf(stdout, fmt, ap);
        va_end(ap);
    }

Which fixes the segv, phew.

John