manifest: for diff(), only iterate over files, not flags
From manifest.diff(), we return a dict from filename to pairs of pairs
of file nodeids and flags (values of the form ((n1,n2),(fl1,fl2))). To
create this dict, we currently generate one dict for files (with
(n1,n2) values) and one for flags (with (fl1,fl2) values) and then
join these dicts. Missing files are represented by None and missing
flags by '', but due to the dict joining, the inner pairs themselves
can also be None. The only caller, merge.manifestmerge(), then unpacks
these values while checking for None values.
By inlining the calls to dicthelpers and simplifying it to only
iterate over files (ignoring flags-only differences), we can simplify
life for our caller.
# manifest.py - manifest revision class for mercurial
#
# Copyright 2005-2007 Matt Mackall <mpm@selenic.com>
#
# 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 mdiff, parsers, error, revlog, util
import array, struct
class manifestdict(dict):
def __init__(self, mapping=None, flags=None):
if mapping is None:
mapping = {}
if flags is None:
flags = {}
dict.__init__(self, mapping)
self._flags = flags
def flags(self, f):
return self._flags.get(f, "")
def withflags(self):
return set(self._flags.keys())
def setflag(self, f, flags):
"""Set the flags (symlink, executable) for path f."""
self._flags[f] = flags
def copy(self):
return manifestdict(self, dict.copy(self._flags))
def intersectfiles(self, files):
'''make a new manifestdict with the intersection of self with files
The algorithm assumes that files is much smaller than self.'''
ret = manifestdict()
for fn in files:
if fn in self:
ret[fn] = self[fn]
flags = self._flags.get(fn, None)
if flags:
ret._flags[fn] = flags
return ret
def diff(self, m2):
'''Finds changes between the current manifest and m2. The result is
returned as a dict with filename as key and values of the form
((n1,n2),(fl1,fl2)), where n1/n2 is the nodeid in the current/other
manifest and fl1/fl2 is the flag in the current/other manifest. Where
the file does not exist, the nodeid will be None and the flags will be
the empty string.'''
diff = {}
for fn, n1 in self.iteritems():
fl1 = self._flags.get(fn, '')
n2 = m2.get(fn, None)
fl2 = m2._flags.get(fn, '')
if n2 is None:
fl2 = ''
if n1 != n2 or fl1 != fl2:
diff[fn] = ((n1, n2), (fl1, fl2))
for fn, n2 in m2.iteritems():
if fn not in self:
fl2 = m2._flags.get(fn, '')
diff[fn] = ((None, n2), ('', fl2))
return diff
def text(self):
"""Get the full data of this manifest as a bytestring."""
fl = sorted(self)
_checkforbidden(fl)
hex, flags = revlog.hex, self.flags
# if this is changed to support newlines in filenames,
# be sure to check the templates/ dir again (especially *-raw.tmpl)
return ''.join("%s\0%s%s\n" % (f, hex(self[f]), flags(f)) for f in fl)
def fastdelta(self, base, changes):
"""Given a base manifest text as an array.array and a list of changes
relative to that text, compute a delta that can be used by revlog.
"""
delta = []
dstart = None
dend = None
dline = [""]
start = 0
# zero copy representation of base as a buffer
addbuf = util.buffer(base)
# start with a readonly loop that finds the offset of
# each line and creates the deltas
for f, todelete in changes:
# bs will either be the index of the item or the insert point
start, end = _msearch(addbuf, f, start)
if not todelete:
l = "%s\0%s%s\n" % (f, revlog.hex(self[f]), self.flags(f))
else:
if start == end:
# item we want to delete was not found, error out
raise AssertionError(
_("failed to remove %s from manifest") % f)
l = ""
if dstart is not None and dstart <= start and dend >= start:
if dend < end:
dend = end
if l:
dline.append(l)
else:
if dstart is not None:
delta.append([dstart, dend, "".join(dline)])
dstart = start
dend = end
dline = [l]
if dstart is not None:
delta.append([dstart, dend, "".join(dline)])
# apply the delta to the base, and get a delta for addrevision
deltatext, arraytext = _addlistdelta(base, delta)
return arraytext, deltatext
def _msearch(m, s, lo=0, hi=None):
'''return a tuple (start, end) that says where to find s within m.
If the string is found m[start:end] are the line containing
that string. If start == end the string was not found and
they indicate the proper sorted insertion point.
m should be a buffer or a string
s is a string'''
def advance(i, c):
while i < lenm and m[i] != c:
i += 1
return i
if not s:
return (lo, lo)
lenm = len(m)
if not hi:
hi = lenm
while lo < hi:
mid = (lo + hi) // 2
start = mid
while start > 0 and m[start - 1] != '\n':
start -= 1
end = advance(start, '\0')
if m[start:end] < s:
# we know that after the null there are 40 bytes of sha1
# this translates to the bisect lo = mid + 1
lo = advance(end + 40, '\n') + 1
else:
# this translates to the bisect hi = mid
hi = start
end = advance(lo, '\0')
found = m[lo:end]
if s == found:
# we know that after the null there are 40 bytes of sha1
end = advance(end + 40, '\n')
return (lo, end + 1)
else:
return (lo, lo)
def _checkforbidden(l):
"""Check filenames for illegal characters."""
for f in l:
if '\n' in f or '\r' in f:
raise error.RevlogError(
_("'\\n' and '\\r' disallowed in filenames: %r") % f)
# apply the changes collected during the bisect loop to our addlist
# return a delta suitable for addrevision
def _addlistdelta(addlist, x):
# for large addlist arrays, building a new array is cheaper
# than repeatedly modifying the existing one
currentposition = 0
newaddlist = array.array('c')
for start, end, content in x:
newaddlist += addlist[currentposition:start]
if content:
newaddlist += array.array('c', content)
currentposition = end
newaddlist += addlist[currentposition:]
deltatext = "".join(struct.pack(">lll", start, end, len(content))
+ content for start, end, content in x)
return deltatext, newaddlist
def _parse(lines):
mfdict = manifestdict()
parsers.parse_manifest(mfdict, mfdict._flags, lines)
return mfdict
class manifest(revlog.revlog):
def __init__(self, opener):
# we expect to deal with not more than four revs at a time,
# during a commit --amend
self._mancache = util.lrucachedict(4)
revlog.revlog.__init__(self, opener, "00manifest.i")
def readdelta(self, node):
r = self.rev(node)
return _parse(mdiff.patchtext(self.revdiff(self.deltaparent(r), r)))
def readfast(self, node):
'''use the faster of readdelta or read'''
r = self.rev(node)
deltaparent = self.deltaparent(r)
if deltaparent != revlog.nullrev and deltaparent in self.parentrevs(r):
return self.readdelta(node)
return self.read(node)
def read(self, node):
if node == revlog.nullid:
return manifestdict() # don't upset local cache
if node in self._mancache:
return self._mancache[node][0]
text = self.revision(node)
arraytext = array.array('c', text)
mapping = _parse(text)
self._mancache[node] = (mapping, arraytext)
return mapping
def find(self, node, f):
'''look up entry for a single file efficiently.
return (node, flags) pair if found, (None, None) if not.'''
if node in self._mancache:
mapping = self._mancache[node][0]
return mapping.get(f), mapping.flags(f)
text = self.revision(node)
start, end = _msearch(text, f)
if start == end:
return None, None
l = text[start:end]
f, n = l.split('\0')
return revlog.bin(n[:40]), n[40:-1]
def add(self, map, transaction, link, p1, p2, added, removed):
if p1 in self._mancache:
# If our first parent is in the manifest cache, we can
# compute a delta here using properties we know about the
# manifest up-front, which may save time later for the
# revlog layer.
_checkforbidden(added)
# combine the changed lists into one list for sorting
work = [(x, False) for x in added]
work.extend((x, True) for x in removed)
# this could use heapq.merge() (from Python 2.6+) or equivalent
# since the lists are already sorted
work.sort()
arraytext, deltatext = map.fastdelta(self._mancache[p1][1], work)
cachedelta = self.rev(p1), deltatext
text = util.buffer(arraytext)
else:
# The first parent manifest isn't already loaded, so we'll
# just encode a fulltext of the manifest and pass that
# through to the revlog layer, and let it handle the delta
# process.
text = map.text()
arraytext = array.array('c', text)
cachedelta = None
n = self.addrevision(text, transaction, link, p1, p2, cachedelta)
self._mancache[n] = (map, arraytext)
return n