Description of problem:

there is a bug in pigz 2.3.3 which can cause an infinite loop when gzipping directories recursively. This is fixed in 2.3.4.

Version-Release number of selected component (if applicable):
pigz 2.3.3

How reproducible:
Very reproducible. If number of files is large and at least two directory levels down, an infinite loop can occur.

Steps to Reproduce:


    mkdir pigztest pigztest/subdir
    cd pigztest
    for ((i=1;i<1000;i++)); do touch  $i.txt; done
    cd subdir/
    for ((i=1;i<1000;i++)); do touch  $i.txt; done
    cd ../..
    pigz -r -v pigztest


Actual results:

With pigz 2.3.3: pigz enters infinite loop iterating over files it created:

pigz: skipping: pigztest/subdir/978.txt.gz ends with .gz
pigz: skipping: pigztest/subdir/962.txt.gz ends with .gz
pigz: skipping: pigztest/subdir/576.txt.gz ends with .gz
pigz: skipping: pigztest/subdir/985.txt.gz ends with .gz
pigz: skipping: pigztest/subdir/764.txt.gz ends with .gz
pigz: skipping: pigztest/subdir/630.txt.gz ends with .gz
pigz: skipping: pigztest/subdir/613.txt.gz ends with .gz
pigz: skipping: pigztest/subdir/841.txt.gz ends with .gz
pigz: skipping: pigztest/subdir/4.txt.gz ends with .gz
pigz: skipping: pigztest/subdir/379.txt.gz ends with .gz
pigz: skipping: pigztest/subdir/402.txt.gz ends with .gz
pigz: skipping: pigztest/subdir/332.txt.gz ends with .gz
pigz: skipping: pigztest/subdir/646.txt.gz ends with .gz
pigz: skipping: pigztest/subdir/450.txt.gz ends with .gz
pigz: skipping: pigztest/subdir/453.txt.gz ends with .gz
pigz: skipping: pigztest/subdir/710.txt.gz ends with .gz
pigz: skipping: pigztest/subdir/490.txt.gz ends with .gz
pigz: skipping: pigztest/subdir/924.txt.gz ends with .gz
pigz: skipping: pigztest/subdir/915.txt.gz ends with .gz

if the -f (force) option is used, every .gz-file is compressed again and again and again ad infinitum.

Expected results:

With pigz 2.3.4, this behavior does not occur. Files are compressed as expected and pigz terminates normally.


Additional info:

pigz version 2.3.4 is already available in Fedora repositories, but for CentOS 
only version 2.3.3 is available via EPEL.

Bugfix is listed in release notes, in the source comments:
https://github.com/madler/pigz/blob/master/pigz.c