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>
This commit is contained in:
John Snow 2020-10-09 12:15:52 -04:00 committed by Markus Armbruster
parent 0cbd5b0516
commit cc6263c44b

View File

@ -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 @@ class QAPIGen:
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: