281 lines
11 KiB
Python
281 lines
11 KiB
Python
#
|
|
# Copyright (c) 2001 - 2017 The SCons Foundation
|
|
#
|
|
# Permission is hereby granted, free of charge, to any person obtaining
|
|
# a copy of this software and associated documentation files (the
|
|
# "Software"), to deal in the Software without restriction, including
|
|
# without limitation the rights to use, copy, modify, merge, publish,
|
|
# distribute, sublicense, and/or sell copies of the Software, and to
|
|
# permit persons to whom the Software is furnished to do so, subject to
|
|
# the following conditions:
|
|
#
|
|
# The above copyright notice and this permission notice shall be included
|
|
# in all copies or substantial portions of the Software.
|
|
#
|
|
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
|
|
# KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
|
|
# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
|
|
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
|
|
# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
|
|
# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
|
|
# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
|
|
#
|
|
|
|
__revision__ = "src/engine/SCons/CacheDir.py 74b2c53bc42290e911b334a6b44f187da698a668 2017/11/14 13:16:53 bdbaddog"
|
|
|
|
__doc__ = """
|
|
CacheDir support
|
|
"""
|
|
|
|
import json
|
|
import os
|
|
import stat
|
|
import sys
|
|
|
|
import SCons.Action
|
|
import SCons.Warnings
|
|
|
|
cache_enabled = True
|
|
cache_debug = False
|
|
cache_force = False
|
|
cache_show = False
|
|
cache_readonly = False
|
|
|
|
def CacheRetrieveFunc(target, source, env):
|
|
t = target[0]
|
|
fs = t.fs
|
|
cd = env.get_CacheDir()
|
|
cachedir, cachefile = cd.cachepath(t)
|
|
if not fs.exists(cachefile):
|
|
cd.CacheDebug('CacheRetrieve(%s): %s not in cache\n', t, cachefile)
|
|
return 1
|
|
cd.CacheDebug('CacheRetrieve(%s): retrieving from %s\n', t, cachefile)
|
|
if SCons.Action.execute_actions:
|
|
if fs.islink(cachefile):
|
|
fs.symlink(fs.readlink(cachefile), t.get_internal_path())
|
|
else:
|
|
env.copy_from_cache(cachefile, t.get_internal_path())
|
|
st = fs.stat(cachefile)
|
|
fs.chmod(t.get_internal_path(), stat.S_IMODE(st[stat.ST_MODE]) | stat.S_IWRITE)
|
|
return 0
|
|
|
|
def CacheRetrieveString(target, source, env):
|
|
t = target[0]
|
|
fs = t.fs
|
|
cd = env.get_CacheDir()
|
|
cachedir, cachefile = cd.cachepath(t)
|
|
if t.fs.exists(cachefile):
|
|
return "Retrieved `%s' from cache" % t.get_internal_path()
|
|
return None
|
|
|
|
CacheRetrieve = SCons.Action.Action(CacheRetrieveFunc, CacheRetrieveString)
|
|
|
|
CacheRetrieveSilent = SCons.Action.Action(CacheRetrieveFunc, None)
|
|
|
|
def CachePushFunc(target, source, env):
|
|
if cache_readonly:
|
|
return
|
|
|
|
t = target[0]
|
|
if t.nocache:
|
|
return
|
|
fs = t.fs
|
|
cd = env.get_CacheDir()
|
|
cachedir, cachefile = cd.cachepath(t)
|
|
if fs.exists(cachefile):
|
|
# Don't bother copying it if it's already there. Note that
|
|
# usually this "shouldn't happen" because if the file already
|
|
# existed in cache, we'd have retrieved the file from there,
|
|
# not built it. This can happen, though, in a race, if some
|
|
# other person running the same build pushes their copy to
|
|
# the cache after we decide we need to build it but before our
|
|
# build completes.
|
|
cd.CacheDebug('CachePush(%s): %s already exists in cache\n', t, cachefile)
|
|
return
|
|
|
|
cd.CacheDebug('CachePush(%s): pushing to %s\n', t, cachefile)
|
|
|
|
tempfile = cachefile+'.tmp'+str(os.getpid())
|
|
errfmt = "Unable to copy %s to cache. Cache file is %s"
|
|
|
|
if not fs.isdir(cachedir):
|
|
try:
|
|
fs.makedirs(cachedir)
|
|
except EnvironmentError:
|
|
# We may have received an exception because another process
|
|
# has beaten us creating the directory.
|
|
if not fs.isdir(cachedir):
|
|
msg = errfmt % (str(target), cachefile)
|
|
raise SCons.Errors.EnvironmentError(msg)
|
|
|
|
try:
|
|
if fs.islink(t.get_internal_path()):
|
|
fs.symlink(fs.readlink(t.get_internal_path()), tempfile)
|
|
else:
|
|
fs.copy2(t.get_internal_path(), tempfile)
|
|
fs.rename(tempfile, cachefile)
|
|
st = fs.stat(t.get_internal_path())
|
|
fs.chmod(cachefile, stat.S_IMODE(st[stat.ST_MODE]) | stat.S_IWRITE)
|
|
except EnvironmentError:
|
|
# It's possible someone else tried writing the file at the
|
|
# same time we did, or else that there was some problem like
|
|
# the CacheDir being on a separate file system that's full.
|
|
# In any case, inability to push a file to cache doesn't affect
|
|
# the correctness of the build, so just print a warning.
|
|
msg = errfmt % (str(target), cachefile)
|
|
SCons.Warnings.warn(SCons.Warnings.CacheWriteErrorWarning, msg)
|
|
|
|
CachePush = SCons.Action.Action(CachePushFunc, None)
|
|
|
|
# Nasty hack to cut down to one warning for each cachedir path that needs
|
|
# upgrading.
|
|
warned = dict()
|
|
|
|
class CacheDir(object):
|
|
|
|
def __init__(self, path):
|
|
try:
|
|
import hashlib
|
|
except ImportError:
|
|
msg = "No hashlib or MD5 module available, CacheDir() not supported"
|
|
SCons.Warnings.warn(SCons.Warnings.NoMD5ModuleWarning, msg)
|
|
path = None
|
|
self.path = path
|
|
self.current_cache_debug = None
|
|
self.debugFP = None
|
|
self.config = dict()
|
|
if path is None:
|
|
return
|
|
# See if there's a config file in the cache directory. If there is,
|
|
# use it. If there isn't, and the directory exists and isn't empty,
|
|
# produce a warning. If the directory doesn't exist or is empty,
|
|
# write a config file.
|
|
config_file = os.path.join(path, 'config')
|
|
if not os.path.exists(config_file):
|
|
# A note: There is a race hazard here, if two processes start and
|
|
# attempt to create the cache directory at the same time. However,
|
|
# python doesn't really give you the option to do exclusive file
|
|
# creation (it doesn't even give you the option to error on opening
|
|
# an existing file for writing...). The ordering of events here
|
|
# as an attempt to alleviate this, on the basis that it's a pretty
|
|
# unlikely occurence (it'd require two builds with a brand new cache
|
|
# directory)
|
|
if os.path.isdir(path) and len(os.listdir(path)) != 0:
|
|
self.config['prefix_len'] = 1
|
|
# When building the project I was testing this on, the warning
|
|
# was output over 20 times. That seems excessive
|
|
global warned
|
|
if self.path not in warned:
|
|
msg = "Please upgrade your cache by running " +\
|
|
" scons-configure-cache.py " + self.path
|
|
SCons.Warnings.warn(SCons.Warnings.CacheVersionWarning, msg)
|
|
warned[self.path] = True
|
|
else:
|
|
if not os.path.isdir(path):
|
|
try:
|
|
os.makedirs(path)
|
|
except OSError:
|
|
# If someone else is trying to create the directory at
|
|
# the same time as me, bad things will happen
|
|
msg = "Failed to create cache directory " + path
|
|
raise SCons.Errors.EnvironmentError(msg)
|
|
|
|
self.config['prefix_len'] = 2
|
|
if not os.path.exists(config_file):
|
|
try:
|
|
with open(config_file, 'w') as config:
|
|
json.dump(self.config, config)
|
|
except:
|
|
msg = "Failed to write cache configuration for " + path
|
|
raise SCons.Errors.EnvironmentError(msg)
|
|
else:
|
|
try:
|
|
with open(config_file) as config:
|
|
self.config = json.load(config)
|
|
except ValueError:
|
|
msg = "Failed to read cache configuration for " + path
|
|
raise SCons.Errors.EnvironmentError(msg)
|
|
|
|
|
|
def CacheDebug(self, fmt, target, cachefile):
|
|
if cache_debug != self.current_cache_debug:
|
|
if cache_debug == '-':
|
|
self.debugFP = sys.stdout
|
|
elif cache_debug:
|
|
self.debugFP = open(cache_debug, 'w')
|
|
else:
|
|
self.debugFP = None
|
|
self.current_cache_debug = cache_debug
|
|
if self.debugFP:
|
|
self.debugFP.write(fmt % (target, os.path.split(cachefile)[1]))
|
|
|
|
def is_enabled(self):
|
|
return cache_enabled and not self.path is None
|
|
|
|
def is_readonly(self):
|
|
return cache_readonly
|
|
|
|
def cachepath(self, node):
|
|
"""
|
|
"""
|
|
if not self.is_enabled():
|
|
return None, None
|
|
|
|
sig = node.get_cachedir_bsig()
|
|
subdir = sig[:self.config['prefix_len']].upper()
|
|
dir = os.path.join(self.path, subdir)
|
|
return dir, os.path.join(dir, sig)
|
|
|
|
def retrieve(self, node):
|
|
"""
|
|
This method is called from multiple threads in a parallel build,
|
|
so only do thread safe stuff here. Do thread unsafe stuff in
|
|
built().
|
|
|
|
Note that there's a special trick here with the execute flag
|
|
(one that's not normally done for other actions). Basically
|
|
if the user requested a no_exec (-n) build, then
|
|
SCons.Action.execute_actions is set to 0 and when any action
|
|
is called, it does its showing but then just returns zero
|
|
instead of actually calling the action execution operation.
|
|
The problem for caching is that if the file does NOT exist in
|
|
cache then the CacheRetrieveString won't return anything to
|
|
show for the task, but the Action.__call__ won't call
|
|
CacheRetrieveFunc; instead it just returns zero, which makes
|
|
the code below think that the file *was* successfully
|
|
retrieved from the cache, therefore it doesn't do any
|
|
subsequent building. However, the CacheRetrieveString didn't
|
|
print anything because it didn't actually exist in the cache,
|
|
and no more build actions will be performed, so the user just
|
|
sees nothing. The fix is to tell Action.__call__ to always
|
|
execute the CacheRetrieveFunc and then have the latter
|
|
explicitly check SCons.Action.execute_actions itself.
|
|
"""
|
|
if not self.is_enabled():
|
|
return False
|
|
|
|
env = node.get_build_env()
|
|
if cache_show:
|
|
if CacheRetrieveSilent(node, [], env, execute=1) == 0:
|
|
node.build(presub=0, execute=0)
|
|
return True
|
|
else:
|
|
if CacheRetrieve(node, [], env, execute=1) == 0:
|
|
return True
|
|
|
|
return False
|
|
|
|
def push(self, node):
|
|
if self.is_readonly() or not self.is_enabled():
|
|
return
|
|
return CachePush(node, [], node.get_build_env())
|
|
|
|
def push_if_forced(self, node):
|
|
if cache_force:
|
|
return self.push(node)
|
|
|
|
# Local Variables:
|
|
# tab-width:4
|
|
# indent-tabs-mode:nil
|
|
# End:
|
|
# vim: set expandtab tabstop=4 shiftwidth=4:
|