qapi/gen.py: update write() to be more idiomatic
Make the file handling here just a tiny bit more idiomatic.
(I realize this is heavily subjective.)
Use exist_ok=True for os.makedirs and remove the exception,
use fdopen() to wrap the file descriptor in a File-like object,
and use a context manager for managing the file pointer.
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Cleber Rosa <crosa@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20201009161558.107041-31-jsnow@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
diff --git a/scripts/qapi/gen.py b/scripts/qapi/gen.py
index 8b851c6..670c21e 100644
--- a/scripts/qapi/gen.py
+++ b/scripts/qapi/gen.py
@@ -12,7 +12,6 @@
# See the COPYING file in the top-level directory.
from contextlib import contextmanager
-import errno
import os
import re
from typing import (
@@ -65,21 +64,19 @@
return
pathname = os.path.join(output_dir, self.fname)
odir = os.path.dirname(pathname)
+
if odir:
- try:
- os.makedirs(odir)
- except os.error as e:
- if e.errno != errno.EEXIST:
- raise
+ os.makedirs(odir, exist_ok=True)
+
+ # use os.open for O_CREAT to create and read a non-existant file
fd = os.open(pathname, os.O_RDWR | os.O_CREAT, 0o666)
- f = open(fd, 'r+', encoding='utf-8')
- text = self.get_content()
- oldtext = f.read(len(text) + 1)
- if text != oldtext:
- f.seek(0)
- f.truncate(0)
- f.write(text)
- f.close()
+ with os.fdopen(fd, 'r+', encoding='utf-8') as fp:
+ text = self.get_content()
+ oldtext = fp.read(len(text) + 1)
+ if text != oldtext:
+ fp.seek(0)
+ fp.truncate(0)
+ fp.write(text)
def _wrap_ifcond(ifcond: List[str], before: str, after: str) -> str: