# posix.py - Posix utility function implementations for Mercurial
#
# Copyright 2005-2009 Matt Mackall <mpm@selenic.com> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from i18n import _
import encoding
import os, sys, errno, stat, getpass, pwd, grp, socket, tempfile, unicodedata
posixfile = open
normpath = os.path.normpath
samestat = os.path.samestat
oslink = os.link
unlink = os.unlink
rename = os.rename
expandglobs = False
umask = os.umask(0)
os.umask(umask)
def split(p):
'''Same as posixpath.split, but faster
>>> import posixpath
>>> for f in ['/absolute/path/to/file',
... 'relative/path/to/file',
... 'file_alone',
... 'path/to/directory/',
... '/multiple/path//separators',
... '/file_at_root',
... '///multiple_leading_separators_at_root',
... '']:
... assert split(f) == posixpath.split(f), f
'''
ht = p.rsplit('/', 1)
if len(ht) == 1:
return '', p
nh = ht[0].rstrip('/')
if nh:
return nh, ht[1]
return ht[0] + '/', ht[1]
def openhardlinks():
'''return true if it is safe to hold open file handles to hardlinks'''
return True
def nlinks(name):
'''return number of hardlinks for the given file'''
return os.lstat(name).st_nlink
def parsepatchoutput(output_line):
"""parses the output produced by patch and returns the filename"""
pf = output_line[14:]
if os.sys.platform == 'OpenVMS':
if pf[0] == '`':
pf = pf[1:-1] # Remove the quotes
else:
if pf.startswith("'") and pf.endswith("'") and " " in pf:
pf = pf[1:-1] # Remove the quotes
return pf
def sshargs(sshcmd, host, user, port):
'''Build argument list for ssh'''
args = user and ("%s@%s" % (user, host)) or host
return port and ("%s -p %s" % (args, port)) or args
def isexec(f):
"""check whether a file is executable"""
return (os.lstat(f).st_mode & 0100 != 0)
def setflags(f, l, x):
s = os.lstat(f).st_mode
if l:
if not stat.S_ISLNK(s):
# switch file to link
fp = open(f)
data = fp.read()
fp.close()
os.unlink(f)
try:
os.symlink(data, f)
except OSError:
# failed to make a link, rewrite file
fp = open(f, "w")
fp.write(data)
fp.close()
# no chmod needed at this point
return
if stat.S_ISLNK(s):
# switch link to file
data = os.readlink(f)
os.unlink(f)
fp = open(f, "w")
fp.write(data)
fp.close()
s = 0666 & ~umask # avoid restatting for chmod
sx = s & 0100
if x and not sx:
# Turn on +x for every +r bit when making a file executable
# and obey umask.
os.chmod(f, s | (s & 0444) >> 2 & ~umask)
elif not x and sx:
# Turn off all +x bits
os.chmod(f, s & 0666)
def copymode(src, dst, mode=None):
'''Copy the file mode from the file at path src to dst.
If src doesn't exist, we're using mode instead. If mode is None, we're
using umask.'''
try:
st_mode = os.lstat(src).st_mode & 0777
except OSError, inst:
if inst.errno != errno.ENOENT:
raise
st_mode = mode
if st_mode is None:
st_mode = ~umask
st_mode &= 0666
os.chmod(dst, st_mode)
def checkexec(path):
"""
Check whether the given path is on a filesystem with UNIX-like exec flags
Requires a directory (like /foo/.hg)
"""
# VFAT on some Linux versions can flip mode but it doesn't persist
# a FS remount. Frequently we can detect it if files are created
# with exec bit on.
try:
EXECFLAGS = stat.S_IXUSR | stat.S_IXGRP | stat.S_IXOTH
fh, fn = tempfile.mkstemp(dir=path, prefix='hg-checkexec-')
try:
os.close(fh)
m = os.stat(fn).st_mode & 0777
new_file_has_exec = m & EXECFLAGS
os.chmod(fn, m ^ EXECFLAGS)
exec_flags_cannot_flip = ((os.stat(fn).st_mode & 0777) == m)
finally:
os.unlink(fn)
except (IOError, OSError):
# we don't care, the user probably won't be able to commit anyway
return False
return not (new_file_has_exec or exec_flags_cannot_flip)
def checklink(path):
"""check whether the given path is on a symlink-capable filesystem"""
# mktemp is not racy because symlink creation will fail if the
# file already exists
name = tempfile.mktemp(dir=path, prefix='hg-checklink-')
try:
os.symlink(".", name)
os.unlink(name)
return True
except (OSError, AttributeError):
return False
def checkosfilename(path):
'''Check that the base-relative path is a valid filename on this platform.
Returns None if the path is ok, or a UI string describing the problem.'''
pass # on posix platforms, every path is ok
def setbinary(fd):
pass
def pconvert(path):
return path
def localpath(path):
return path
def samefile(fpath1, fpath2):
"""Returns whether path1 and path2 refer to the same file. This is only
guaranteed to work for files, not directories."""
return os.path.samefile(fpath1, fpath2)
def samedevice(fpath1, fpath2):
"""Returns whether fpath1 and fpath2 are on the same device. This is only
guaranteed to work for files, not directories."""
st1 = os.lstat(fpath1)
st2 = os.lstat(fpath2)
return st1.st_dev == st2.st_dev
# os.path.normcase is a no-op, which doesn't help us on non-native filesystems
def normcase(path):
return path.lower()
if sys.platform == 'darwin':
import fcntl # only needed on darwin, missing on jython
def normcase(path):
try:
path.decode('ascii') # throw exception for non-ASCII character
return path.lower()
except UnicodeDecodeError:
pass
try:
u = path.decode('utf-8')
except UnicodeDecodeError:
# percent-encode any characters that don't round-trip
p2 = path.decode('utf-8', 'ignore').encode('utf-8')
s = ""
pos = 0
for c in path:
if p2[pos:pos + 1] == c:
s += c
pos += 1
else:
s += "%%%02X" % ord(c)
u = s.decode('utf-8')
# Decompose then lowercase (HFS+ technote specifies lower)
return unicodedata.normalize('NFD', u).lower().encode('utf-8')
def realpath(path):
'''
Returns the true, canonical file system path equivalent to the given
path.
Equivalent means, in this case, resulting in the same, unique
file system link to the path. Every file system entry, whether a file,
directory, hard link or symbolic link or special, will have a single
path preferred by the system, but may allow multiple, differing path
lookups to point to it.
Most regular UNIX file systems only allow a file system entry to be
looked up by its distinct path. Obviously, this does not apply to case
insensitive file systems, whether case preserving or not. The most
complex issue to deal with is file systems transparently reencoding the
path, such as the non-standard Unicode normalisation required for HFS+
and HFSX.
'''
# Constants copied from /usr/include/sys/fcntl.h
F_GETPATH = 50
O_SYMLINK = 0x200000
try:
fd = os.open(path, O_SYMLINK)
except OSError, err:
if err.errno == errno.ENOENT:
return path
raise
try:
return fcntl.fcntl(fd, F_GETPATH, '\0' * 1024).rstrip('\0')
finally:
os.close(fd)
elif sys.version_info < (2, 4, 2, 'final'):
# Workaround for http://bugs.python.org/issue1213894 (os.path.realpath
# didn't resolve symlinks that were the first component of the path.)
def realpath(path):
if os.path.isabs(path):
return os.path.realpath(path)
else:
return os.path.realpath('./' + path)
else:
# Fallback to the likely inadequate Python builtin function.
realpath = os.path.realpath
if sys.platform == 'cygwin':
# workaround for cygwin, in which mount point part of path is
# treated as case sensitive, even though underlying NTFS is case
# insensitive.
# default mount points
cygwinmountpoints = sorted([
"/usr/bin",
"/usr/lib",
"/cygdrive",
], reverse=True)
# use upper-ing as normcase as same as NTFS workaround
def normcase(path):
pathlen = len(path)
if (pathlen == 0) or (path[0] != os.sep):
# treat as relative
return encoding.upper(path)
# to preserve case of mountpoint part
for mp in cygwinmountpoints:
if not path.startswith(mp):
continue
mplen = len(mp)
if mplen == pathlen: # mount point itself
return mp
if path[mplen] == os.sep:
return mp + encoding.upper(path[mplen:])
return encoding.upper(path)
# Cygwin translates native ACLs to POSIX permissions,
# but these translations are not supported by native
# tools, so the exec bit tends to be set erroneously.
# Therefore, disable executable bit access on Cygwin.
def checkexec(path):
return False
# Similarly, Cygwin's symlink emulation is likely to create
# problems when Mercurial is used from both Cygwin and native
# Windows, with other native tools, or on shared volumes
def checklink(path):
return False
def shellquote(s):
if os.sys.platform == 'OpenVMS':
return '"%s"' % s
else:
return "'%s'" % s.replace("'", "'\\''")
def quotecommand(cmd):
return cmd
def popen(command, mode='r'):
return os.popen(command, mode)
def testpid(pid):
'''return False if pid dead, True if running or not sure'''
if os.sys.platform == 'OpenVMS':
return True
try:
os.kill(pid, 0)
return True
except OSError, inst:
return inst.errno != errno.ESRCH
def explainexit(code):
"""return a 2-tuple (desc, code) describing a subprocess status
(codes from kill are negative - not os.system/wait encoding)"""
if code >= 0:
return _("exited with status %d") % code, code
return _("killed by signal %d") % -code, -code
def isowner(st):
"""Return True if the stat object st is from the current user."""
return st.st_uid == os.getuid()
def findexe(command):
'''Find executable for command searching like which does.
If command is a basename then PATH is searched for command.
PATH isn't searched if command is an absolute or relative path.
If command isn't found None is returned.'''
if sys.platform == 'OpenVMS':
return command
def findexisting(executable):
'Will return executable if existing file'
if os.path.isfile(executable) and os.access(executable, os.X_OK):
return executable
return None
if os.sep in command:
return findexisting(command)
if sys.platform == 'plan9':
return findexisting(os.path.join('/bin', command))
for path in os.environ.get('PATH', '').split(os.pathsep):
executable = findexisting(os.path.join(path, command))
if executable is not None:
return executable
return None
def setsignalhandler():
pass
_wantedkinds = set([stat.S_IFREG, stat.S_IFLNK])
def statfiles(files):
'''Stat each file in files. Yield each stat, or None if a file does not
exist or has a type we don't care about.'''
lstat = os.lstat
getkind = stat.S_IFMT
for nf in files:
try:
st = lstat(nf)
if getkind(st.st_mode) not in _wantedkinds:
st = None
except OSError, err:
if err.errno not in (errno.ENOENT, errno.ENOTDIR):
raise
st = None
yield st
def getuser():
'''return name of current user'''
return getpass.getuser()
def username(uid=None):
"""Return the name of the user with the given uid.
If uid is None, return the name of the current user."""
if uid is None:
uid = os.getuid()
try:
return pwd.getpwuid(uid)[0]
except KeyError:
return str(uid)
def groupname(gid=None):
"""Return the name of the group with the given gid.
If gid is None, return the name of the current group."""
if gid is None:
gid = os.getgid()
try:
return grp.getgrgid(gid)[0]
except KeyError:
return str(gid)
def groupmembers(name):
"""Return the list of members of the group with the given
name, KeyError if the group does not exist.
"""
return list(grp.getgrnam(name).gr_mem)
def spawndetached(args):
return os.spawnvp(os.P_NOWAIT | getattr(os, 'P_DETACH', 0),
args[0], args)
def gethgcmd():
return sys.argv[:1]
def termwidth():
try:
import termios, array, fcntl
for dev in (sys.stderr, sys.stdout, sys.stdin):
try:
try:
fd = dev.fileno()
except AttributeError:
continue
if not os.isatty(fd):
continue
try:
arri = fcntl.ioctl(fd, termios.TIOCGWINSZ, '\0' * 8)
width = array.array('h', arri)[1]
if width > 0:
return width
except AttributeError:
pass
except ValueError:
pass
except IOError, e:
if e[0] == errno.EINVAL:
pass
else:
raise
except ImportError:
pass
return 80
def makedir(path, notindexed):
os.mkdir(path)
def unlinkpath(f, ignoremissing=False):
"""unlink and remove the directory if it is empty"""
try:
os.unlink(f)
except OSError, e:
if not (ignoremissing and e.errno == errno.ENOENT):
raise
# try removing directories that might now be empty
try:
os.removedirs(os.path.dirname(f))
except OSError:
pass
def lookupreg(key, name=None, scope=None):
return None
def hidewindow():
"""Hide current shell window.
Used to hide the window opened when starting asynchronous
child process under Windows, unneeded on other systems.
"""
pass
class cachestat(object):
def __init__(self, path):
self.stat = os.stat(path)
def cacheable(self):
return bool(self.stat.st_ino)
__hash__ = object.__hash__
def __eq__(self, other):
try:
# Only dev, ino, size, mtime and atime are likely to change. Out
# of these, we shouldn't compare atime but should compare the
# rest. However, one of the other fields changing indicates
# something fishy going on, so return False if anything but atime
# changes.
return (self.stat.st_mode == other.stat.st_mode and
self.stat.st_ino == other.stat.st_ino and
self.stat.st_dev == other.stat.st_dev and
self.stat.st_nlink == other.stat.st_nlink and
self.stat.st_uid == other.stat.st_uid and
self.stat.st_gid == other.stat.st_gid and
self.stat.st_size == other.stat.st_size and
self.stat.st_mtime == other.stat.st_mtime and
self.stat.st_ctime == other.stat.st_ctime)
except AttributeError:
return False
def __ne__(self, other):
return not self == other
def executablepath():
return None # available on Windows only
class unixdomainserver(socket.socket):
def __init__(self, join, subsystem):
'''Create a unix domain socket with the given prefix.'''
super(unixdomainserver, self).__init__(socket.AF_UNIX)
sockname = subsystem + '.sock'
self.realpath = self.path = join(sockname)
if os.path.islink(self.path):
if os.path.exists(self.path):
self.realpath = os.readlink(self.path)
else:
os.unlink(self.path)
try:
self.bind(self.realpath)
except socket.error, err:
if err.args[0] == 'AF_UNIX path too long':
tmpdir = tempfile.mkdtemp(prefix='hg-%s-' % subsystem)
self.realpath = os.path.join(tmpdir, sockname)
try:
self.bind(self.realpath)
os.symlink(self.realpath, self.path)
except (OSError, socket.error):
self.cleanup()
raise
else:
raise
self.listen(5)
def cleanup(self):
def okayifmissing(f, path):
try:
f(path)
except OSError, err:
if err.errno != errno.ENOENT:
raise
okayifmissing(os.unlink, self.path)
if self.realpath != self.path:
okayifmissing(os.unlink, self.realpath)
okayifmissing(os.rmdir, os.path.dirname(self.realpath))