~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

from shutil import copyfile

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

                  S_ISCHR, S_ISBLK, S_ISFIFO, S_ISSOCK)

from cStringIO import StringIO

import errno

import os

import re

import sha

import sys

import time

import types

import bzrlib

from bzrlib.errors import BzrError

from bzrlib.trace import mutter

def make_readonly(filename):

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

    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 = None

def quotefn(f):

    """Return a quoted filename filename

    This previously used backslash quoting, but that works poorly on

    Windows."""

    # TODO: I'm not really sure this is the best format either.x

    global _QUOTE_RE

    if _QUOTE_RE == None:

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

    if _QUOTE_RE.search(f):

        return '"' + f + '"'

    else:

        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'

    elif S_ISCHR(mode):

        return 'chardev'

    elif S_ISBLK(mode):

        return 'block'

    elif S_ISFIFO(mode):

        return 'fifo'

    elif S_ISSOCK(mode):

        return 'socket'

    else:

        return 'unknown'

def kind_marker(kind):

    if kind == 'file':

        return ''

    elif kind == 'directory':

        return '/'

    elif kind == 'symlink':

        return '@'

    else:

        raise BzrError('invalid file kind %r' % kind)

def lexists(f):

    try:

        if hasattr(os, 'lstat'):

            os.lstat(f)

        else:

            os.stat(f)

        return True

    except OSError,e:

        if e.errno == errno.ENOENT:

            return False;

        else:

            raise BzrError("lstat/stat of (%r): %r" % (f, e))

def normalizepath(f):

    if hasattr(os.path, 'realpath'):

        F = os.path.realpath

    else:

        F = os.path.abspath

    [p,e] = os.path.split(f)

    if e == "" or e == "." or e == "..":

        return F(f)

    else:

        return os.path.join(F(p), e)

def backup_file(fn):

    """Copy a file to a backup.

    Backups are named in GNU-style, with a ~ suffix.

    If the file is already a backup, it's not copied.

    """

    if fn[-1] == '~':

        return

    bfn = fn + '~'

    if has_symlinks() and os.path.islink(fn):

        target = os.readlink(fn)

        os.symlink(target, bfn)

        return

    inf = file(fn, 'rb')

    try:

        content = inf.read()

    finally:

        inf.close()

    outf = file(bfn, 'wb')

    try:

        outf.write(content)

    finally:

        outf.close()

if os.name == 'nt':

    import shutil

    rename = shutil.move

else:

    rename = os.rename

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 islink(f):

    """True if f is a symlink."""

    try:

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

    except OSError:

        return False

def is_inside(dir, fname):

    """True if fname is inside dir.

    The parameters should typically be passed to os.path.normpath first, so

    that . and .. and repeated slashes are eliminated, and the separators

    are canonical for the platform.

    The empty string as a dir name is taken as top-of-tree and matches 

    everything.

    >>> is_inside('src', os.path.join('src', 'foo.c'))

    True

    >>> is_inside('src', 'srccontrol')

    False

    >>> is_inside('src', os.path.join('src', 'a', 'a', 'a', 'foo.c'))

    True

    >>> is_inside('foo.c', 'foo.c')

    True

    >>> is_inside('foo.c', '')

    False

    >>> is_inside('', 'foo.c')

    True

    """

    # XXX: Most callers of this can actually do something smarter by 

    # looking at the inventory

    if dir == fname:

        return True

    if dir == '':

        return True

    if dir[-1] != os.sep:

        dir += os.sep

    return fname.startswith(dir)

def is_inside_any(dir_list, fname):

    """True if fname is inside any of given dirs."""

    for dirname in dir_list:

        if is_inside(dirname, fname):

            return True

    else:

        return False

def pumpfile(fromfile, tofile):

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

    tofile.write(fromfile.read())

def sha_file(f):

    if hasattr(f, 'tell'):

        assert f.tell() == 0

    s = sha.new()

    BUFSIZE = 128<<10

    while True:

        b = f.read(BUFSIZE)

        if not b:

            break

        s.update(b)

    return s.hexdigest()

def sha_strings(strings):

    """Return the sha-1 of concatenation of strings"""

    s = sha.new()

    map(s.update, strings)

    return s.hexdigest()

def sha_string(f):

    s = sha.new()

    s.update(f)

    return s.hexdigest()

def fingerprint_file(f):

    s = sha.new()

    b = f.read()

    s.update(b)

    size = len(b)

    return {'size': size,

            'sha1': s.hexdigest()}

def compare_files(a, b):

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

    BUFSIZE = 4096

    while True:

        ai = a.read(BUFSIZE)

        bi = b.read(BUFSIZE)

        if ai != bi:

            return False

        if ai == '':

            return True

def local_time_offset(t=None):

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

    # python2.3 localtime() can't take None

    if t == None:

        t = time.time()

    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?

    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:

        raise BzrError("unsupported timezone format %r" % timezone,

                       ['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]

# Define rand_bytes based on platform.

try:

    # Python 2.4 and later have os.urandom,

    # but it doesn't work on some arches

    os.urandom(1)

    rand_bytes = os.urandom

except (NotImplementedError, AttributeError):

    # If python doesn't have os.urandom, or it doesn't work,

    # then try to first pull random data from /dev/urandom

    if os.path.exists("/dev/urandom"):

        rand_bytes = file('/dev/urandom', 'rb').read

    # Otherwise, use this hack as a last resort

    else:

        # not well seeded, but better than nothing

        def rand_bytes(n):

            import random

            s = ''

            while n:

                s += chr(random.randint(0, 255))

                n -= 1

            return s

## 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)

    # split on either delimiter because people might use either on

    # Windows

    ps = re.split(r'[\\/]', p)

    rps = []

    for f in ps:

        if f == '..':

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

        elif (f == '.') or (f == ''):

            pass

        else:

            rps.append(f)

    return rps

def joinpath(p):

    assert isinstance(p, list)

    for f in p:

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

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

    return os.path.join(*p)

def appendpath(p1, p2):

    if p1 == '':

        return p2

    else:

        return os.path.join(p1, p2)

def split_lines(s):

    """Split s into lines, but without removing the newline characters."""

    return StringIO(s).readlines()

def hardlinks_good():

    return sys.platform not in ('win32', 'cygwin', 'darwin')

def link_or_copy(src, dest):

    """Hardlink a file, or copy it if it can't be hardlinked."""

    if not hardlinks_good():

        copyfile(src, dest)

        return

    try:

        os.link(src, dest)

    except (OSError, IOError), e:

        if e.errno != errno.EXDEV:

            raise

        copyfile(src, dest)

def has_symlinks():

    if hasattr(os, 'symlink'):

        return True

    else:

        return False