mirror of
https://github.com/kovidgoyal/calibre.git
synced 2025-07-09 03:04:10 -04:00
Use atomic writes for the config files
Avoids the need for file locking and also ensures no partial data is written in case of crash/powerloss. Fixes #1964123 [Settings reset in main calibre program when pc turns off due to power failure](https://bugs.launchpad.net/calibre/+bug/1964123)
This commit is contained in:
Kovid Goyal
parent
15ded1182f
commit
007099dd60
@ -15,12 +15,10 @@ from calibre.constants import (
|
||||
)
|
||||
from calibre.utils.config_base import (
|
||||
Config, ConfigInterface, ConfigProxy, Option, OptionSet, OptionValues,
|
||||
StringConfig, json_dumps, json_loads, make_config_dir, plugin_dir, prefs,
|
||||
tweaks, from_json, to_json
|
||||
StringConfig, commit_data, from_json, json_dumps, json_loads, make_config_dir,
|
||||
plugin_dir, prefs, read_data, to_json, tweaks
|
||||
)
|
||||
from calibre.utils.lock import ExclusiveFile
|
||||
from polyglot.builtins import string_or_bytes, native_string_type
|
||||
|
||||
from polyglot.builtins import native_string_type, string_or_bytes
|
||||
|
||||
# optparse uses gettext.gettext instead of _ from builtins, so we
|
||||
# monkey patch it.
|
||||
@ -29,7 +27,7 @@ optparse._ = _
|
||||
if False:
|
||||
# Make pyflakes happy
|
||||
Config, ConfigProxy, Option, OptionValues, StringConfig, OptionSet,
|
||||
ConfigInterface, tweaks, plugin_dir, prefs, from_json, to_json
|
||||
ConfigInterface, tweaks, plugin_dir, prefs, from_json, to_json, make_config_dir
|
||||
|
||||
|
||||
def check_config_write_access():
|
||||
@ -53,6 +51,7 @@ class CustomHelpFormatter(optparse.IndentedHelpFormatter):
|
||||
|
||||
def format_option(self, option):
|
||||
import textwrap
|
||||
|
||||
from calibre.utils.terminal import colored
|
||||
|
||||
result = []
|
||||
@ -91,6 +90,7 @@ class OptionParser(optparse.OptionParser):
|
||||
conflict_handler='resolve',
|
||||
**kwds):
|
||||
import textwrap
|
||||
|
||||
from calibre.utils.terminal import colored
|
||||
|
||||
usage = textwrap.dedent(usage)
|
||||
@ -219,8 +219,8 @@ class DynamicConfig(dict):
|
||||
self.refresh()
|
||||
|
||||
def read_old_serialized_representation(self):
|
||||
from calibre.utils.shared_file import share_open
|
||||
from calibre.utils.serialize import pickle_loads
|
||||
from calibre.utils.shared_file import share_open
|
||||
path = self.file_path.rpartition('.')[0]
|
||||
try:
|
||||
with share_open(path, 'rb') as f:
|
||||
@ -238,9 +238,12 @@ class DynamicConfig(dict):
|
||||
migrate = False
|
||||
if clear_current:
|
||||
self.clear()
|
||||
if os.path.exists(self.file_path):
|
||||
with ExclusiveFile(self.file_path) as f:
|
||||
raw = f.read()
|
||||
try:
|
||||
raw = read_data(self.file_path)
|
||||
except FileNotFoundError:
|
||||
d = self.read_old_serialized_representation()
|
||||
migrate = bool(d)
|
||||
else:
|
||||
if raw:
|
||||
try:
|
||||
d = json_loads(raw)
|
||||
@ -250,14 +253,9 @@ class DynamicConfig(dict):
|
||||
else:
|
||||
d = self.read_old_serialized_representation()
|
||||
migrate = bool(d)
|
||||
else:
|
||||
d = self.read_old_serialized_representation()
|
||||
migrate = bool(d)
|
||||
if migrate and d:
|
||||
raw = json_dumps(d, ignore_unserializable=True)
|
||||
with ExclusiveFile(self.file_path) as f:
|
||||
f.seek(0), f.truncate()
|
||||
f.write(raw)
|
||||
commit_data(self.file_path, raw)
|
||||
|
||||
self.update(d)
|
||||
|
||||
@ -283,13 +281,8 @@ class DynamicConfig(dict):
|
||||
def commit(self):
|
||||
if not getattr(self, 'name', None):
|
||||
return
|
||||
if not os.path.exists(self.file_path):
|
||||
make_config_dir()
|
||||
raw = json_dumps(self)
|
||||
with ExclusiveFile(self.file_path) as f:
|
||||
f.seek(0)
|
||||
f.truncate()
|
||||
f.write(raw)
|
||||
commit_data(self.file_path, raw)
|
||||
|
||||
|
||||
dynamic = DynamicConfig()
|
||||
@ -345,9 +338,11 @@ class XMLConfig(dict):
|
||||
|
||||
def refresh(self, clear_current=True):
|
||||
d = {}
|
||||
if os.path.exists(self.file_path):
|
||||
with ExclusiveFile(self.file_path) as f:
|
||||
raw = f.read()
|
||||
try:
|
||||
raw = read_data(self.file_path)
|
||||
except FileNotFoundError:
|
||||
pass
|
||||
else:
|
||||
try:
|
||||
d = self.raw_to_object(raw) if raw.strip() else {}
|
||||
except SystemError:
|
||||
@ -393,15 +388,11 @@ class XMLConfig(dict):
|
||||
def commit(self):
|
||||
if self.no_commit:
|
||||
return
|
||||
if hasattr(self, 'file_path') and self.file_path:
|
||||
if getattr(self, 'file_path', None):
|
||||
dpath = os.path.dirname(self.file_path)
|
||||
if not os.path.exists(dpath):
|
||||
os.makedirs(dpath, mode=CONFIG_DIR_MODE)
|
||||
with ExclusiveFile(self.file_path) as f:
|
||||
raw = self.to_raw()
|
||||
f.seek(0)
|
||||
f.truncate()
|
||||
f.write(raw)
|
||||
commit_data(self.file_path, self.to_raw())
|
||||
|
||||
def __enter__(self):
|
||||
self.no_commit = True
|
||||
|
||||
@ -5,11 +5,11 @@ __copyright__ = '2011, Kovid Goyal <kovid@kovidgoyal.net>'
|
||||
__docformat__ = 'restructuredtext en'
|
||||
|
||||
import os, re, traceback, numbers
|
||||
from contextlib import suppress
|
||||
from functools import partial
|
||||
from collections import defaultdict
|
||||
from copy import deepcopy
|
||||
|
||||
from calibre.utils.lock import ExclusiveFile
|
||||
from calibre.constants import config_dir, CONFIG_DIR_MODE, preferred_encoding, filesystem_encoding, iswindows
|
||||
from polyglot.builtins import iteritems
|
||||
|
||||
@ -344,6 +344,34 @@ class ConfigInterface:
|
||||
self.option_set.smart_update(opts1, opts2)
|
||||
|
||||
|
||||
def read_data(file_path, count=10, sleep_time=0.2):
|
||||
import time
|
||||
count = 10
|
||||
for i in range(count):
|
||||
try:
|
||||
with open(file_path, 'rb') as f:
|
||||
return f.read()
|
||||
except FileNotFoundError:
|
||||
raise
|
||||
except OSError:
|
||||
if i > count - 2:
|
||||
raise
|
||||
# Try the operation repeatedly in case something like a virus
|
||||
# scanner has opened one of the files (I love windows)
|
||||
time.sleep(sleep_time)
|
||||
|
||||
|
||||
def commit_data(file_path, data):
|
||||
import tempfile
|
||||
|
||||
from calibre.utils.filenames import atomic_rename
|
||||
bdir = os.path.dirname(file_path)
|
||||
os.makedirs(bdir, exist_ok=True, mode=CONFIG_DIR_MODE)
|
||||
with tempfile.NamedTemporaryFile(dir=bdir, delete=False) as f:
|
||||
f.write(data)
|
||||
atomic_rename(f.name, file_path)
|
||||
|
||||
|
||||
class Config(ConfigInterface):
|
||||
'''
|
||||
A file based configuration.
|
||||
@ -361,10 +389,10 @@ class Config(ConfigInterface):
|
||||
src = ''
|
||||
migrate = False
|
||||
path = self.config_file_path
|
||||
if os.path.exists(path):
|
||||
with ExclusiveFile(path) as f:
|
||||
with suppress(FileNotFoundError):
|
||||
src_bytes = read_data(path)
|
||||
try:
|
||||
src = f.read().decode('utf-8')
|
||||
src = src_bytes.decode('utf-8')
|
||||
except ValueError:
|
||||
print("Failed to parse", path)
|
||||
traceback.print_exc()
|
||||
@ -381,9 +409,7 @@ class Config(ConfigInterface):
|
||||
ans = self.option_set.parse_string(src)
|
||||
if migrate:
|
||||
new_src = self.option_set.serialize(ans, ignore_unserializable=True)
|
||||
with ExclusiveFile(self.config_file_path) as f:
|
||||
f.seek(0), f.truncate()
|
||||
f.write(new_src)
|
||||
commit_data(self.config_file_path, new_src)
|
||||
return ans
|
||||
|
||||
def set(self, name, val):
|
||||
@ -391,16 +417,13 @@ class Config(ConfigInterface):
|
||||
raise ValueError('The option %s is not defined.'%name)
|
||||
if not os.path.exists(config_dir):
|
||||
make_config_dir()
|
||||
with ExclusiveFile(self.config_file_path) as f:
|
||||
src = f.read()
|
||||
src = read_data(self.config_file_path)
|
||||
opts = self.option_set.parse_string(src)
|
||||
setattr(opts, name, val)
|
||||
src = self.option_set.serialize(opts)
|
||||
f.seek(0)
|
||||
f.truncate()
|
||||
if isinstance(src, str):
|
||||
src = src.encode('utf-8')
|
||||
f.write(src)
|
||||
commit_data(self.config_file_path, src)
|
||||
|
||||
|
||||
class StringConfig(ConfigInterface):
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user