From cfde364a20a133873edbc1d77dcb59c4fb47fc3c Mon Sep 17 00:00:00 2001 From: Thomas Grainger Date: Tue, 10 Dec 2024 07:40:54 +0000 Subject: [PATCH] gh-126775: make linecache.checkcache threadsafe and GC re-entrency safe (GH-126776) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit (cherry picked from commit 2233c303e476496fc4c85a29a1429a7e4b1f707b) Co-authored-by: Thomas Grainger Co-authored-by: blurb-it[bot] <43283697+blurb-it[bot]@users.noreply.github.com> Co-authored-by: Bartosz Sławecki --- Lib/linecache.py | 13 ++++++++----- .../2024-11-13-10-44-25.gh-issue-126775.a3ubjh.rst | 1 + 2 files changed, 9 insertions(+), 5 deletions(-) create mode 100644 Misc/NEWS.d/next/Library/2024-11-13-10-44-25.gh-issue-126775.a3ubjh.rst diff --git a/Lib/linecache.py b/Lib/linecache.py index 4b38a0464d8747..8ba2df73d5a8fb 100644 --- a/Lib/linecache.py +++ b/Lib/linecache.py @@ -49,14 +49,17 @@ def checkcache(filename=None): (This is not checked upon each call!)""" if filename is None: - filenames = list(cache.keys()) - elif filename in cache: - filenames = [filename] + # get keys atomically + filenames = cache.copy().keys() else: - return + filenames = [filename] for filename in filenames: - entry = cache[filename] + try: + entry = cache[filename] + except KeyError: + continue + if len(entry) == 1: # lazy cache entry, leave it lazy. continue diff --git a/Misc/NEWS.d/next/Library/2024-11-13-10-44-25.gh-issue-126775.a3ubjh.rst b/Misc/NEWS.d/next/Library/2024-11-13-10-44-25.gh-issue-126775.a3ubjh.rst new file mode 100644 index 00000000000000..429fc2aa17bd42 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2024-11-13-10-44-25.gh-issue-126775.a3ubjh.rst @@ -0,0 +1 @@ +Make :func:`linecache.checkcache` thread safe and GC re-entrancy safe.