~bzr-pqm/bzr/bzr.dev

# Bazaar-NG -- distributed version control

# Copyright (C) 2005 by Canonical Ltd

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

import os, types, re, time, types

from stat import S_ISREG, S_ISDIR, S_ISLNK, ST_MODE, ST_SIZE

from errors import bailout

def make_readonly(filename):

    """Make a filename read-only."""

    # TODO: probably needs to be fixed for windows

    mod = os.stat(filename).st_mode

    mod = mod & 0777555

    os.chmod(filename, mod)

def make_writable(filename):

    mod = os.stat(filename).st_mode

    mod = mod | 0200

    os.chmod(filename, mod)

_QUOTE_RE = re.compile(r'([^a-zA-Z0-9.,:/_~-])')

def quotefn(f):

    """Return shell-quoted filename"""

    ## We could be a bit more terse by using double-quotes etc

    f = _QUOTE_RE.sub(r'\\\1', f)

    if f[0] == '~':

        f[0:1] = r'\~' 

    return f

def file_kind(f):

    mode = os.lstat(f)[ST_MODE]

    if S_ISREG(mode):

        return 'file'

    elif S_ISDIR(mode):

        return 'directory'

    elif S_ISLNK(mode):

        return 'symlink'

    else:

        bailout("can't handle file kind with mode %o of %r" % (mode, f)) 

def isdir(f):

    """True if f is an accessible directory."""

    try:

        return S_ISDIR(os.lstat(f)[ST_MODE])

    except OSError:

        return False

def isfile(f):

    """True if f is a regular file."""

    try:

        return S_ISREG(os.lstat(f)[ST_MODE])

    except OSError:

        return False

def pumpfile(fromfile, tofile):

    """Copy contents of one file to another."""

    tofile.write(fromfile.read())

def uuid():

    """Return a new UUID"""

    ## XXX: Could alternatively read /proc/sys/kernel/random/uuid on

    ## Linux, but we need something portable for other systems;

    ## preferably an implementation in Python.

    try:

        return chomp(file('/proc/sys/kernel/random/uuid').readline())

    except IOError:

        return chomp(os.popen('uuidgen').readline())

def chomp(s):

    if s and (s[-1] == '\n'):

        return s[:-1]

    else:

        return s

def sha_file(f):

    import sha

    ## TODO: Maybe read in chunks to handle big files

    if hasattr(f, 'tell'):

        assert f.tell() == 0

    s = sha.new()

    s.update(f.read())

    return s.hexdigest()

def sha_string(f):

    import sha

    s = sha.new()

    s.update(f)

    return s.hexdigest()

def username():

    """Return email-style username.

    Something similar to 'Martin Pool <mbp@sourcefrog.net>'

    :todo: Check it's reasonably well-formed.

    :todo: Allow taking it from a dotfile to help people on windows

           who can't easily set variables.

    :todo: Cope without pwd module, which is only on unix. 

    """

    e = os.environ.get('BZREMAIL') or os.environ.get('EMAIL')

    if e: return e

    import socket

    try:

        import pwd

        uid = os.getuid()

        w = pwd.getpwuid(uid)

        gecos = w.pw_gecos

        comma = gecos.find(',')

        if comma == -1:

            realname = gecos

        else:

            realname = gecos[:comma]

        return '%s <%s@%s>' % (realname, w.pw_name, socket.getfqdn())

    except ImportError:

        pass

    import getpass, socket

    return '<%s@%s>' % (getpass.getuser(), socket.getfqdn())

def user_email():

    """Return just the email component of a username."""

    e = os.environ.get('BZREMAIL') or os.environ.get('EMAIL')

    if e:

        import re

        m = re.search(r'[\w+.-]+@[\w+.-]+', e)

        if not m:

            bailout('%r is not a reasonable email address' % e)

        return m.group(0)

    import getpass, socket

    return '%s@%s' % (getpass.getuser(), socket.getfqdn())

def compare_files(a, b):

    """Returns true if equal in contents"""

    # TODO: don't read the whole thing in one go.

    result = a.read() == b.read()

    return result

def local_time_offset(t=None):

    """Return offset of local zone from GMT, either at present or at time t."""

    if time.localtime(t).tm_isdst and time.daylight:

        return -time.altzone

    else:

        return -time.timezone

def format_date(t, offset=0, timezone='original'):

    ## TODO: Perhaps a global option to use either universal or local time?

    ## Or perhaps just let people set $TZ?

    import time

    assert isinstance(t, float)

    if timezone == 'utc':

        tt = time.gmtime(t)

        offset = 0

    elif timezone == 'original':

        if offset == None:

            offset = 0

        tt = time.gmtime(t + offset)

    elif timezone == 'local':

        tt = time.localtime(t)

        offset = local_time_offset(t)

    else:

        bailout("unsupported timezone format %r",

                ['options are "utc", "original", "local"'])

    return (time.strftime("%a %Y-%m-%d %H:%M:%S", tt)

            + ' %+03d%02d' % (offset / 3600, (offset / 60) % 60))

def compact_date(when):

    return time.strftime('%Y%m%d%H%M%S', time.gmtime(when))

def filesize(f):

    """Return size of given open file."""

    return os.fstat(f.fileno())[ST_SIZE]

if hasattr(os, 'urandom'): # python 2.4 and later

    rand_bytes = os.urandom

else:

    # FIXME: No good on non-Linux

    _rand_file = file('/dev/urandom', 'rb')

    rand_bytes = _rand_file.read

## TODO: We could later have path objects that remember their list

## decomposition (might be too tricksy though.)

def splitpath(p):

    """Turn string into list of parts.

    >>> splitpath('a')

    ['a']

    >>> splitpath('a/b')

    ['a', 'b']

    >>> splitpath('a/./b')

    ['a', 'b']

    >>> splitpath('a/.b')

    ['a', '.b']

    >>> splitpath('a/../b')

    Traceback (most recent call last):

    ...

    BzrError: ("sorry, '..' not allowed in path", [])

    """

    assert isinstance(p, types.StringTypes)

    ps = [f for f in p.split('/') if f != '.']

    for f in ps:

        if f == '..':

            bailout("sorry, %r not allowed in path" % f)

    return ps

def joinpath(p):

    assert isinstance(p, list)

    for f in p:

        if (f == '..') or (f is None) or (f == ''):

            bailout("sorry, %r not allowed in path" % f)

    return '/'.join(p)

def appendpath(p1, p2):

    if p1 == '':

        return p2

    else:

        return p1 + '/' + p2

def extern_command(cmd, ignore_errors = False):

    mutter('external command: %s' % `cmd`)

    if os.system(cmd):

        if not ignore_errors:

            bailout('command failed')