Mercurial > hg-stable
view setup.py @ 13704:a464763e99f1
dirstate: avoid a race with multiple commits in the same process
(issue2264, issue2516)
The race happens when two commits in a row change the same file
without changing its size, *if* those two commits happen in the same
second in the same process while holding the same repo lock. For
example:
commit 1:
M a
M b
commit 2: # same process, same second, same repo lock
M b # modify b without changing its size
M c
This first manifested in transplant, which is the most common way to
do multiple commits in the same process. But it can manifest in any
script or extension that does multiple commits under the same repo
lock. (Thus, the test script tests both transplant and a custom script.)
The problem was that dirstate.status() failed to notice the change to
b when localrepo is about to do the second commit, meaning that change
gets left in the working directory. In the context of transplant, that
means either a crash ("RuntimeError: nothing committed after
transplant") or a silently inaccurate transplant, depending on whether
any other files were modified by the second transplanted changeset.
The fix is to make status() work a little harder when we have
previously marked files as clean (state 'normal') in the same process.
Specifically, dirstate.normal() adds files to self._lastnormal, and
other state-changing methods remove them. Then dirstate.status() puts
any files in self._lastnormal into state 'lookup', which will make
localrepository.status() read file contents to see if it has really
changed. So we pay a small performance penalty for the second (and
subsequent) commits in the same process, without affecting the common
case. Anything that does lots of status updates and checks in the
same process could suffer a performance hit.
Incidentally, there is a simpler fix: call dirstate.normallookup() on
every file updated by commit() at the end of the commit. The trouble
with that solution is that it imposes a performance penalty on the
common case: it means the next status-dependent hg command after every
"hg commit" will be a little bit slower. The patch here is more
complex, but only affects performance for the uncommon case.
author | Greg Ward <greg@gerg.ca> |
---|---|
date | Sun, 20 Mar 2011 17:41:09 -0400 |
parents | 4e976235c985 |
children | 16118b4859a1 |
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# # This is the mercurial setup script. # # 'python setup.py install', or # 'python setup.py --help' for more options import sys if not hasattr(sys, 'version_info') or sys.version_info < (2, 4, 0, 'final'): raise SystemExit("Mercurial requires Python 2.4 or later.") if sys.version_info[0] >= 3: def b(s): '''A helper function to emulate 2.6+ bytes literals using string literals.''' return s.encode('latin1') else: def b(s): '''A helper function to emulate 2.6+ bytes literals using string literals.''' return s # Solaris Python packaging brain damage try: import hashlib sha = hashlib.sha1() except: try: import sha except: raise SystemExit( "Couldn't import standard hashlib (incomplete Python install).") try: import zlib except: raise SystemExit( "Couldn't import standard zlib (incomplete Python install).") try: import bz2 except: raise SystemExit( "Couldn't import standard bz2 (incomplete Python install).") import os, subprocess, time import shutil import tempfile from distutils import log from distutils.core import setup, Extension from distutils.dist import Distribution from distutils.command.build import build from distutils.command.build_ext import build_ext from distutils.command.build_py import build_py from distutils.command.install_scripts import install_scripts from distutils.spawn import spawn, find_executable from distutils.ccompiler import new_compiler from distutils.errors import CCompilerError from distutils.sysconfig import get_python_inc from distutils.version import StrictVersion scripts = ['hg'] if os.name == 'nt': scripts.append('contrib/win32/hg.bat') # simplified version of distutils.ccompiler.CCompiler.has_function # that actually removes its temporary files. def hasfunction(cc, funcname): tmpdir = tempfile.mkdtemp(prefix='hg-install-') devnull = oldstderr = None try: try: fname = os.path.join(tmpdir, 'funcname.c') f = open(fname, 'w') f.write('int main(void) {\n') f.write(' %s();\n' % funcname) f.write('}\n') f.close() # Redirect stderr to /dev/null to hide any error messages # from the compiler. # This will have to be changed if we ever have to check # for a function on Windows. devnull = open('/dev/null', 'w') oldstderr = os.dup(sys.stderr.fileno()) os.dup2(devnull.fileno(), sys.stderr.fileno()) objects = cc.compile([fname], output_dir=tmpdir) cc.link_executable(objects, os.path.join(tmpdir, "a.out")) except: return False return True finally: if oldstderr is not None: os.dup2(oldstderr, sys.stderr.fileno()) if devnull is not None: devnull.close() shutil.rmtree(tmpdir) # py2exe needs to be installed to work try: import py2exe py2exeloaded = True except ImportError: py2exeloaded = False def runcmd(cmd, env): p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, env=env) out, err = p.communicate() return out, err def runhg(cmd, env): out, err = runcmd(cmd, env) # If root is executing setup.py, but the repository is owned by # another user (as in "sudo python setup.py install") we will get # trust warnings since the .hg/hgrc file is untrusted. That is # fine, we don't want to load it anyway. Python may warn about # a missing __init__.py in mercurial/locale, we also ignore that. err = [e for e in err.splitlines() if not e.startswith(b('Not trusting file')) \ and not e.startswith(b('warning: Not importing'))] if err: return '' return out version = '' if os.path.isdir('.hg'): # Execute hg out of this directory with a custom environment which # includes the pure Python modules in mercurial/pure. We also take # care to not use any hgrc files and do no localization. pypath = ['mercurial', os.path.join('mercurial', 'pure')] env = {'PYTHONPATH': os.pathsep.join(pypath), 'HGRCPATH': '', 'LANGUAGE': 'C'} if 'LD_LIBRARY_PATH' in os.environ: env['LD_LIBRARY_PATH'] = os.environ['LD_LIBRARY_PATH'] if 'SystemRoot' in os.environ: # Copy SystemRoot into the custom environment for Python 2.6 # under Windows. Otherwise, the subprocess will fail with # error 0xc0150004. See: http://bugs.python.org/issue3440 env['SystemRoot'] = os.environ['SystemRoot'] cmd = [sys.executable, 'hg', 'id', '-i', '-t'] l = runhg(cmd, env).split() while len(l) > 1 and l[-1][0].isalpha(): # remove non-numbered tags l.pop() if len(l) > 1: # tag found version = l[-1] if l[0].endswith('+'): # propagate the dirty status to the tag version += '+' elif len(l) == 1: # no tag found cmd = [sys.executable, 'hg', 'parents', '--template', '{latesttag}+{latesttagdistance}-'] version = runhg(cmd, env) + l[0] if version.endswith('+'): version += time.strftime('%Y%m%d') elif os.path.exists('.hg_archival.txt'): kw = dict([[t.strip() for t in l.split(':', 1)] for l in open('.hg_archival.txt')]) if 'tag' in kw: version = kw['tag'] elif 'latesttag' in kw: version = '%(latesttag)s+%(latesttagdistance)s-%(node).12s' % kw else: version = kw.get('node', '')[:12] if version: f = open("mercurial/__version__.py", "w") f.write('# this file is autogenerated by setup.py\n') f.write('version = "%s"\n' % version) f.close() try: from mercurial import __version__ version = __version__.version except ImportError: version = 'unknown' class hgbuildmo(build): description = "build translations (.mo files)" def run(self): if not find_executable('msgfmt'): self.warn("could not find msgfmt executable, no translations " "will be built") return podir = 'i18n' if not os.path.isdir(podir): self.warn("could not find %s/ directory" % podir) return join = os.path.join for po in os.listdir(podir): if not po.endswith('.po'): continue pofile = join(podir, po) modir = join('locale', po[:-3], 'LC_MESSAGES') mofile = join(modir, 'hg.mo') mobuildfile = join('mercurial', mofile) cmd = ['msgfmt', '-v', '-o', mobuildfile, pofile] if sys.platform != 'sunos5': # msgfmt on Solaris does not know about -c cmd.append('-c') self.mkpath(join('mercurial', modir)) self.make_file([pofile], mobuildfile, spawn, (cmd,)) # Insert hgbuildmo first so that files in mercurial/locale/ are found # when build_py is run next. build.sub_commands.insert(0, ('build_mo', None)) Distribution.pure = 0 Distribution.global_options.append(('pure', None, "use pure (slow) Python " "code instead of C extensions")) class hgbuildext(build_ext): def build_extension(self, ext): try: build_ext.build_extension(self, ext) except CCompilerError: if not getattr(ext, 'optional', False): raise log.warn("Failed to build optional extension '%s' (skipping)", ext.name) class hgbuildpy(build_py): def finalize_options(self): build_py.finalize_options(self) if self.distribution.pure: if self.py_modules is None: self.py_modules = [] for ext in self.distribution.ext_modules: if ext.name.startswith("mercurial."): self.py_modules.append("mercurial.pure.%s" % ext.name[10:]) self.distribution.ext_modules = [] else: if not os.path.exists(os.path.join(get_python_inc(), 'Python.h')): raise SystemExit("Python headers are required to build Mercurial") def find_modules(self): modules = build_py.find_modules(self) for module in modules: if module[0] == "mercurial.pure": if module[1] != "__init__": yield ("mercurial", module[1], module[2]) else: yield module class hginstallscripts(install_scripts): ''' This is a specialization of install_scripts that replaces the @LIBDIR@ with the configured directory for modules. If possible, the path is made relative to the directory for scripts. ''' def initialize_options(self): install_scripts.initialize_options(self) self.install_lib = None def finalize_options(self): install_scripts.finalize_options(self) self.set_undefined_options('install', ('install_lib', 'install_lib')) def run(self): install_scripts.run(self) if (os.path.splitdrive(self.install_dir)[0] != os.path.splitdrive(self.install_lib)[0]): # can't make relative paths from one drive to another, so use an # absolute path instead libdir = self.install_lib else: common = os.path.commonprefix((self.install_dir, self.install_lib)) rest = self.install_dir[len(common):] uplevel = len([n for n in os.path.split(rest) if n]) libdir = uplevel * ('..' + os.sep) + self.install_lib[len(common):] for outfile in self.outfiles: fp = open(outfile, 'rb') data = fp.read() fp.close() # skip binary files if '\0' in data: continue data = data.replace('@LIBDIR@', libdir.encode('string_escape')) fp = open(outfile, 'wb') fp.write(data) fp.close() cmdclass = {'build_mo': hgbuildmo, 'build_ext': hgbuildext, 'build_py': hgbuildpy, 'install_scripts': hginstallscripts} packages = ['mercurial', 'mercurial.hgweb', 'hgext', 'hgext.convert', 'hgext.highlight', 'hgext.zeroconf'] pymodules = [] extmodules = [ Extension('mercurial.base85', ['mercurial/base85.c']), Extension('mercurial.bdiff', ['mercurial/bdiff.c']), Extension('mercurial.diffhelpers', ['mercurial/diffhelpers.c']), Extension('mercurial.mpatch', ['mercurial/mpatch.c']), Extension('mercurial.parsers', ['mercurial/parsers.c']), ] # disable osutil.c under windows + python 2.4 (issue1364) if sys.platform == 'win32' and sys.version_info < (2, 5, 0, 'final'): pymodules.append('mercurial.pure.osutil') else: extmodules.append(Extension('mercurial.osutil', ['mercurial/osutil.c'])) if sys.platform == 'linux2' and os.uname()[2] > '2.6': # The inotify extension is only usable with Linux 2.6 kernels. # You also need a reasonably recent C library. # In any case, if it fails to build the error will be skipped ('optional'). cc = new_compiler() if hasfunction(cc, 'inotify_add_watch'): inotify = Extension('hgext.inotify.linux._inotify', ['hgext/inotify/linux/_inotify.c'], ['mercurial']) inotify.optional = True extmodules.append(inotify) packages.extend(['hgext.inotify', 'hgext.inotify.linux']) packagedata = {'mercurial': ['locale/*/LC_MESSAGES/hg.mo', 'help/*.txt']} def ordinarypath(p): return p and p[0] != '.' and p[-1] != '~' for root in ('templates',): for curdir, dirs, files in os.walk(os.path.join('mercurial', root)): curdir = curdir.split(os.sep, 1)[1] dirs[:] = filter(ordinarypath, dirs) for f in filter(ordinarypath, files): f = os.path.join(curdir, f) packagedata['mercurial'].append(f) datafiles = [] setupversion = version extra = {} if py2exeloaded: extra['console'] = [ {'script':'hg', 'copyright':'Copyright (C) 2005-2010 Matt Mackall and others', 'product_version':version}] if os.name == 'nt': # Windows binary file versions for exe/dll files must have the # form W.X.Y.Z, where W,X,Y,Z are numbers in the range 0..65535 setupversion = version.split('+', 1)[0] if sys.platform == 'darwin' and os.path.exists('/usr/bin/xcodebuild'): # XCode 4.0 dropped support for ppc architecture, which is hardcoded in # distutils.sysconfig version = runcmd(['/usr/bin/xcodebuild', '-version'], {})[0].splitlines()[0] # Also parse only first digit, because 3.2.1 can't be parsed nicely if (version.startswith('Xcode') and StrictVersion(version.split()[1]) >= StrictVersion('4.0')): os.environ['ARCHFLAGS'] = '-arch i386 -arch x86_64' setup(name='mercurial', version=setupversion, author='Matt Mackall', author_email='mpm@selenic.com', url='http://mercurial.selenic.com/', description='Scalable distributed SCM', license='GNU GPLv2+', scripts=scripts, packages=packages, py_modules=pymodules, ext_modules=extmodules, data_files=datafiles, package_data=packagedata, cmdclass=cmdclass, options=dict(py2exe=dict(packages=['hgext', 'email']), bdist_mpkg=dict(zipdist=True, license='COPYING', readme='contrib/macosx/Readme.html', welcome='contrib/macosx/Welcome.html')), **extra)