ghostscript: avoid log=None construct

src/ocrmypdf/exec/ghostscript.py

@@ -15,6 +15,7 @@
 # You should have received a copy of the GNU General Public License
 # along with OCRmyPDF.  If not, see <http://www.gnu.org/licenses/>.
 
+import logging
 import re
 from functools import lru_cache
 from os import fspath
@@ -24,8 +25,11 @@ from tempfile import NamedTemporaryFile
 
 from PIL import Image
 
-from . import get_version
 from ..exceptions import SubprocessOutputError
+from . import get_version
+
+
+gslog = logging.getLogger()
 
 
 @lru_cache(maxsize=1)
@@ -132,6 +136,8 @@ def rasterize_pdf(
     res = round(xres, 6), round(yres, 6)
     if not page_dpi:
         page_dpi = res
+    if not log:
+        log = gslog
 
     with NamedTemporaryFile(delete=True) as tmp:
         args_gs = (
@@ -209,6 +215,9 @@ def generate_pdfa(
     images entirely. (The feature was added in 9.23 but broken, and the 9.24
     release of Ghostscript had regressions, so we don't support it until 9.25.)
     """
+    if not log:
+        log = gslog
+
     compression_args = []
     if compression == 'jpeg':
         compression_args = [