view mercurial/posix.py @ 8294:48a382c23226

transaction: refactor transaction.abort and rollback to use the same code

This adds a change to the way that abort is processed, as it will not continue
truncating files beyond the first failure, otherwise the respective
functionality is maintained, i.e. abort will not unlink files, but rollback
will.

Co-contributor: Sune Foldager <[e-mail]>

# posix.py - Posix utility function implementations for Mercurial
#
#  Copyright 2005-2009 Matt Mackall <[e-mail]> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2, incorporated herein by reference.

from i18n import _
import os, sys, osutil, errno, stat, getpass, pwd, grp

posixfile = file
nulldev = '/dev/null'
normpath = os.path.normpath
samestat = os.path.samestat

umask = os.umask(0)
os.umask(umask)

def openhardlinks():
    '''return true if it is safe to hold open file handles to hardlinks'''
    return True

def rcfiles(path):
    rcs = [os.path.join(path, 'hgrc')]
    rcdir = os.path.join(path, 'hgrc.d')
    try:
        rcs.extend([os.path.join(rcdir, f)
                    for f, kind in osutil.listdir(rcdir)
                    if f.endswith(".rc")])
    except OSError:
        pass
    return rcs

def system_rcpath():
    path = []
    # old mod_python does not set sys.argv
    if len(getattr(sys, 'argv', [])) > 0:
        path.extend(rcfiles(os.path.dirname(sys.argv[0]) +
                              '/../etc/mercurial'))
    path.extend(rcfiles('/etc/mercurial'))
    return path

def user_rcpath():
    return [os.path.expanduser('~/.hgrc')]

def parse_patch_output(output_line):
    """parses the output produced by patch and returns the file name"""
    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 is_exec(f):
    """check whether a file is executable"""
    return (os.lstat(f).st_mode & 0100 != 0)

def set_flags(f, l, x):
    s = os.lstat(f).st_mode
    if l:
        if not stat.S_ISLNK(s):
            # switch file to link
            data = file(f).read()
            os.unlink(f)
            try:
                os.symlink(data, f)
            except:
                # failed to make a link, rewrite file
                file(f, "w").write(data)
        # no chmod needed at this point
        return
    if stat.S_ISLNK(s):
        # switch link to file
        data = os.readlink(f)
        os.unlink(f)
        file(f, "w").write(data)
        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 set_binary(fd):
    pass

def pconvert(path):
    return path

def localpath(path):
    return path

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 explain_exit(code):
    """return a 2-tuple (desc, code) describing a process's status"""
    if os.WIFEXITED(code):
        val = os.WEXITSTATUS(code)
        return _("exited with status %d") % val, val
    elif os.WIFSIGNALED(code):
        val = os.WTERMSIG(code)
        return _("killed by signal %d") % val, val
    elif os.WIFSTOPPED(code):
        val = os.WSTOPSIG(code)
        return _("stopped by signal %d") % val, val
    raise ValueError(_("invalid exit code"))

def isowner(fp, st=None):
    """Return True if the file object f belongs to the current user.

    The return value of a util.fstat(f) may be passed as the st argument.
    """
    if st is None:
        st = fstat(fp)
    return st.st_uid == os.getuid()

def find_exe(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.exists(executable):
            return executable
        return None

    if os.sep in command:
        return findexisting(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 set_signal_handler():
    pass

def statfiles(files):
    'Stat each file in files and yield stat or None if file does not exist.'
    lstat = os.lstat
    for nf in files:
        try:
            st = lstat(nf)
        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 expand_glob(pats):
    '''On Windows, expand the implicit globs in a list of patterns'''
    return list(pats)

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)