# store.py - repository store handling for Mercurial
#
# Copyright 2008 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms
# of the GNU General Public License, incorporated herein by reference.
from i18n import _
import os, stat, osutil, util
_sha = util.sha1
def _buildencodefun():
e = '_'
win_reserved = [ord(x) for x in '\\:*?"<>|']
cmap = dict([ (chr(x), chr(x)) for x in xrange(127) ])
for x in (range(32) + range(126, 256) + win_reserved):
cmap[chr(x)] = "~%02x" % x
for x in range(ord("A"), ord("Z")+1) + [ord(e)]:
cmap[chr(x)] = e + chr(x).lower()
dmap = {}
for k, v in cmap.iteritems():
dmap[v] = k
def decode(s):
i = 0
while i < len(s):
for l in xrange(1, 4):
try:
yield dmap[s[i:i+l]]
i += l
break
except KeyError:
pass
else:
raise KeyError
return (lambda s: "".join([cmap[c] for c in s]),
lambda s: "".join(list(decode(s))))
encodefilename, decodefilename = _buildencodefun()
def _build_lower_encodefun():
win_reserved = [ord(x) for x in '\\:*?"<>|']
cmap = dict([ (chr(x), chr(x)) for x in xrange(127) ])
for x in (range(32) + range(126, 256) + win_reserved):
cmap[chr(x)] = "~%02x" % x
for x in range(ord("A"), ord("Z")+1):
cmap[chr(x)] = chr(x).lower()
return lambda s: "".join([cmap[c] for c in s])
lowerencode = _build_lower_encodefun()
_windows_reserved_filenames = '''con prn aux nul
com1 com2 com3 com4 com5 com6 com7 com8 com9
lpt1 lpt2 lpt3 lpt4 lpt5 lpt6 lpt7 lpt8 lpt9'''.split()
def auxencode(path):
res = []
for n in path.split('/'):
if n:
base = n.split('.')[0]
if base and (base in _windows_reserved_filenames):
# encode third letter ('aux' -> 'au~78')
ec = "~%02x" % ord(n[2])
n = n[0:2] + ec + n[3:]
if n[-1] in '. ':
# encode last period or space ('foo...' -> 'foo..~2e')
n = n[:-1] + "~%02x" % ord(n[-1])
res.append(n)
return '/'.join(res)
MAX_PATH_LEN_IN_HGSTORE = 120
DIR_PREFIX_LEN = 8
_MAX_SHORTENED_DIRS_LEN = 8 * (DIR_PREFIX_LEN + 1) - 4
def hybridencode(path):
'''encodes path with a length limit
Encodes all paths that begin with 'data/', according to the following.
Default encoding (reversible):
Encodes all uppercase letters 'X' as '_x'. All reserved or illegal
characters are encoded as '~xx', where xx is the two digit hex code
of the character (see encodefilename).
Relevant path components consisting of Windows reserved filenames are
masked by encoding the third character ('aux' -> 'au~78', see auxencode).
Hashed encoding (not reversible):
If the default-encoded path is longer than MAX_PATH_LEN_IN_HGSTORE, a
non-reversible hybrid hashing of the path is done instead.
This encoding uses up to DIR_PREFIX_LEN characters of all directory
levels of the lowerencoded path, but not more levels than can fit into
_MAX_SHORTENED_DIRS_LEN.
Then follows the filler followed by the sha digest of the full path.
The filler is the beginning of the basename of the lowerencoded path
(the basename is everything after the last path separator). The filler
is as long as possible, filling in characters from the basename until
the encoded path has MAX_PATH_LEN_IN_HGSTORE characters (or all chars
of the basename have been taken).
The extension (e.g. '.i' or '.d') is preserved.
The string 'data/' at the beginning is replaced with 'dh/', if the hashed
encoding was used.
'''
if not path.startswith('data/'):
return path
ndpath = path[len('data/'):]
res = 'data/' + auxencode(encodefilename(ndpath))
if len(res) > MAX_PATH_LEN_IN_HGSTORE:
digest = _sha(path).hexdigest()
aep = auxencode(lowerencode(ndpath))
_root, ext = os.path.splitext(aep)
parts = aep.split('/')
basename = parts[-1]
sdirs = []
for p in parts[:-1]:
d = p[:DIR_PREFIX_LEN]
if d[-1] in '. ':
# Windows can't access dirs ending in period or space
d = d[:-1] + '_'
t = '/'.join(sdirs) + '/' + d
if len(t) > _MAX_SHORTENED_DIRS_LEN:
break
sdirs.append(d)
dirs = '/'.join(sdirs)
if len(dirs) > 0:
dirs += '/'
res = 'dh/' + dirs + digest + ext
space_left = MAX_PATH_LEN_IN_HGSTORE - len(res)
if space_left > 0:
filler = basename[:space_left]
res = 'dh/' + dirs + filler + digest + ext
return res
def _calcmode(path):
try:
# files in .hg/ will be created using this mode
mode = os.stat(path).st_mode
# avoid some useless chmods
if (0777 & ~util._umask) == (0777 & mode):
mode = None
except OSError:
mode = None
return mode
_data = 'data 00manifest.d 00manifest.i 00changelog.d 00changelog.i'
class basicstore:
'''base class for local repository stores'''
def __init__(self, path, opener, pathjoiner):
self.pathjoiner = pathjoiner
self.path = path
self.createmode = _calcmode(path)
self.opener = opener(self.path)
self.opener.createmode = self.createmode
def join(self, f):
return self.pathjoiner(self.path, f)
def _walk(self, relpath, recurse):
'''yields (unencoded, encoded, size)'''
path = self.pathjoiner(self.path, relpath)
striplen = len(self.path) + len(os.sep)
l = []
if os.path.isdir(path):
visit = [path]
while visit:
p = visit.pop()
for f, kind, st in osutil.listdir(p, stat=True):
fp = self.pathjoiner(p, f)
if kind == stat.S_IFREG and f[-2:] in ('.d', '.i'):
n = util.pconvert(fp[striplen:])
l.append((n, n, st.st_size))
elif kind == stat.S_IFDIR and recurse:
visit.append(fp)
return util.sort(l)
def datafiles(self):
return self._walk('data', True)
def walk(self):
'''yields (unencoded, encoded, size)'''
# yield data files first
for x in self.datafiles():
yield x
# yield manifest before changelog
meta = self._walk('', False)
meta.reverse()
for x in meta:
yield x
def copylist(self):
return ['requires'] + _data.split()
class encodedstore(basicstore):
def __init__(self, path, opener, pathjoiner):
self.pathjoiner = pathjoiner
self.path = self.pathjoiner(path, 'store')
self.createmode = _calcmode(self.path)
op = opener(self.path)
op.createmode = self.createmode
self.opener = lambda f, *args, **kw: op(encodefilename(f), *args, **kw)
def datafiles(self):
for a, b, size in self._walk('data', True):
try:
a = decodefilename(a)
except KeyError:
a = None
yield a, b, size
def join(self, f):
return self.pathjoiner(self.path, encodefilename(f))
def copylist(self):
return (['requires', '00changelog.i'] +
[self.pathjoiner('store', f) for f in _data.split()])
def fncache(opener):
'''yields the entries in the fncache file'''
try:
fp = opener('fncache', mode='rb')
except IOError:
# skip nonexistent file
return
for n, line in enumerate(fp):
if (len(line) < 2) or (line[-1] != '\n'):
t = _('invalid entry in fncache, line %s') % (n + 1)
raise util.Abort(t)
yield line[:-1]
fp.close()
class fncacheopener(object):
def __init__(self, opener):
self.opener = opener
self.entries = None
def loadfncache(self):
self.entries = {}
for f in fncache(self.opener):
self.entries[f] = True
def __call__(self, path, mode='r', *args, **kw):
if mode not in ('r', 'rb') and path.startswith('data/'):
if self.entries is None:
self.loadfncache()
if path not in self.entries:
self.opener('fncache', 'ab').write(path + '\n')
# fncache may contain non-existent files after rollback / strip
self.entries[path] = True
return self.opener(hybridencode(path), mode, *args, **kw)
class fncachestore(basicstore):
def __init__(self, path, opener, pathjoiner):
self.pathjoiner = pathjoiner
self.path = self.pathjoiner(path, 'store')
self.createmode = _calcmode(self.path)
self._op = opener(self.path)
self._op.createmode = self.createmode
self.opener = fncacheopener(self._op)
def join(self, f):
return self.pathjoiner(self.path, hybridencode(f))
def datafiles(self):
rewrite = False
existing = []
pjoin = self.pathjoiner
spath = self.path
for f in fncache(self._op):
ef = hybridencode(f)
try:
st = os.stat(pjoin(spath, ef))
yield f, ef, st.st_size
existing.append(f)
except OSError:
# nonexistent entry
rewrite = True
if rewrite:
# rewrite fncache to remove nonexistent entries
# (may be caused by rollback / strip)
fp = self._op('fncache', mode='wb')
for p in existing:
fp.write(p + '\n')
fp.close()
def copylist(self):
d = _data + ' dh fncache'
return (['requires', '00changelog.i'] +
[self.pathjoiner('store', f) for f in d.split()])
def store(requirements, path, opener, pathjoiner=None):
pathjoiner = pathjoiner or os.path.join
if 'store' in requirements:
if 'fncache' in requirements:
return fncachestore(path, opener, pathjoiner)
return encodedstore(path, opener, pathjoiner)
return basicstore(path, opener, pathjoiner)