Re: pnm loader fixes and tests

["Matthias Clasen" <matthiasc poet de>]

> 
> You might want to add a 
> 
>   TEST_RANDOMLY_MODIFIED (valid_ppm_1, FALSE);
> 
> This tests takes a valid image and modifies the bytes in it - it was
> very good at breaking some of the other loaders.

Yes, these random tests are pretty good. 

TEST_RANDOM ('P', 150, FALSE);

allowed me to catch one more buffer overrun in the pnm loader.

Matthias