[plugins] Don't tail gzipped files when reaching sizelimit

In case sizelimit in add_copy_spec is reached and tailit=True, we shall
skip tailing a gzip archive that would be collected as damaged.

Resolves: #907

Signed-off-by: Pavel Moravec <pmoravec@redhat.com>
Signed-off-by: Bryn M. Reeves <bmr@redhat.com>

1 files changed, 11 insertions, 1 deletions

diff --git a/sos/plugins/__init__.py b/sos/plugins/__init__.py
index 632e2f5f..28c6f197 100644
--- a/sos/plugins/__init__.py
+++ b/sos/plugins/__init__.py
@@ -81,6 +81,16 @@ def _node_type(st):
             return t[1]
 
 
+def _file_is_compressed(path):
+    """Check if a file appears to be compressed
+
+    Return True if the file specified by path appears to be compressed,
+    or False otherwise by testing the file name extension against a
+    list of known file compression extentions.
+    """
+    return path.endswith(('.gz', '.xz', '.bz', '.bz2'))
+
+
 class Plugin(object):
     """ This is the base class for sosreport plugins. Plugins should subclass
     this and set the class variables where applicable.
@@ -564,7 +574,7 @@ class Plugin(object):
                     break
                 self._add_copy_paths([_file])
 
-            if limit_reached and tailit:
+            if limit_reached and tailit and not _file_is_compressed(_file):
                 file_name = _file
 
                 if file_name[0] == os.sep: