From 324a1e1aed7847cd5d054c8507a3d12484fb1260 Mon Sep 17 00:00:00 2001
From: Kovid Goyal <kovid@kovidgoyal.net>
Date: Mon, 16 Oct 2023 12:25:57 +0530
Subject: [PATCH] More explicit resource closage

---
 src/calibre/db/cache.py            | 19 +++++++++----------
 src/calibre/db/tests/filesystem.py |  8 ++++++--
 src/calibre/utils/exim.py          |  1 +
 3 files changed, 16 insertions(+), 12 deletions(-)

diff --git a/src/calibre/db/cache.py b/src/calibre/db/cache.py
index 314dbebea2..db670318fc 100644
--- a/src/calibre/db/cache.py
+++ b/src/calibre/db/cache.py
@@ -3480,18 +3480,17 @@ def import_library(library_key, importer, library_path, progress=None, abort=Non
         cache._update_path((book_id,), mark_as_dirtied=False)
         for fmt, fmtkey in iteritems(fmt_key_map):
             if fmt == '.cover':
-                stream = importer.start_file(fmtkey, _('Cover for %s') % title)
-                path = cache._field_for('path', book_id).replace('/', os.sep)
-                cache.backend.set_cover(book_id, path, stream, no_processing=True)
+                with closing(importer.start_file(fmtkey, _('Cover for %s') % title)) as stream:
+                    path = cache._field_for('path', book_id).replace('/', os.sep)
+                    cache.backend.set_cover(book_id, path, stream, no_processing=True)
             else:
-                stream = importer.start_file(fmtkey, _('{0} format for {1}').format(fmt.upper(), title))
-                size, fname = cache._do_add_format(book_id, fmt, stream, mtime=stream.mtime)
-                cache.fields['formats'].table.update_fmt(book_id, fmt, fname, size, cache.backend)
-            stream.close()
+                with closing(importer.start_file(fmtkey, _('{0} format for {1}').format(fmt.upper(), title))) as stream:
+                    size, fname = cache._do_add_format(book_id, fmt, stream, mtime=stream.mtime)
+                    cache.fields['formats'].table.update_fmt(book_id, fmt, fname, size, cache.backend)
         for relpath, efkey in extra_files.get(book_id, {}).items():
-            stream = importer.start_file(efkey, _('Extra file {0} for book {1}').format(relpath, title))
-            path = cache._field_for('path', book_id).replace('/', os.sep)
-            cache.backend.add_extra_file(relpath, stream, path)
+            with closing(importer.start_file(efkey, _('Extra file {0} for book {1}').format(relpath, title))) as stream:
+                path = cache._field_for('path', book_id).replace('/', os.sep)
+                cache.backend.add_extra_file(relpath, stream, path)
         cache.dump_metadata({book_id})
     if progress is not None:
         progress(_('Completed'), total, total)
diff --git a/src/calibre/db/tests/filesystem.py b/src/calibre/db/tests/filesystem.py
index 476404168b..eb4784d97f 100644
--- a/src/calibre/db/tests/filesystem.py
+++ b/src/calibre/db/tests/filesystem.py
@@ -239,6 +239,10 @@ class FilesystemTest(BaseTest):
     def test_export_import(self):
         from calibre.db.cache import import_library
         from calibre.utils.exim import Exporter, Importer
+        def read(x, mode='r'):
+            with open(x, mode) as f:
+                return f.read()
+
         cache = self.init_cache()
         bookdir = os.path.dirname(cache.format_abspath(1, '__COVER_INTERNAL__'))
         with open(os.path.join(bookdir, 'exf'), 'w') as f:
@@ -262,8 +266,8 @@ class FilesystemTest(BaseTest):
                         self.assertEqual(cache.format(book_id, fmt), ic.format(book_id, fmt))
                         self.assertEqual(cache.format_metadata(book_id, fmt)['mtime'], cache.format_metadata(book_id, fmt)['mtime'])
                 bookdir = os.path.dirname(ic.format_abspath(1, '__COVER_INTERNAL__'))
-                self.assertEqual('exf', open(os.path.join(bookdir, 'exf')).read())
-                self.assertEqual('recurse', open(os.path.join(bookdir, 'sub', 'recurse')).read())
+                self.assertEqual('exf', read(os.path.join(bookdir, 'exf')))
+                self.assertEqual('recurse', read(os.path.join(bookdir, 'sub', 'recurse')))
         r1 = cache.add_notes_resource(b'res1', 'res.jpg', mtime=time.time()-113)
         r2 = cache.add_notes_resource(b'res2', 'res.jpg', mtime=time.time()-1115)
         cache.set_notes_for('authors', 2, 'some notes', resource_hashes=(r1, r2))
diff --git a/src/calibre/utils/exim.py b/src/calibre/utils/exim.py
index 3415a58229..21413045cf 100644
--- a/src/calibre/utils/exim.py
+++ b/src/calibre/utils/exim.py
@@ -256,6 +256,7 @@ class FileSource:
     def close(self):
         if self.check_hash and self.hasher.hexdigest() != self.digest:
             self.importer.corrupted_files.append(self.description)
+        self.f.close()
         self.hasher = self.f = None