revlog.py
854 lines
| 29.2 KiB
| text/x-python
|
PythonLexer
/ mercurial / revlog.py
|
r1083 | """ | ||
revlog.py - storage back-end for mercurial | ||||
This provides efficient delta storage with O(1) retrieve and append | ||||
and O(changes) merge between branches | ||||
Copyright 2005 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. | ||||
""" | ||||
|
r0 | |||
|
r1089 | from node import * | ||
|
r1400 | from i18n import gettext as _ | ||
|
r1322 | from demandload import demandload | ||
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r1325 | demandload(globals(), "binascii errno heapq mdiff sha struct zlib") | ||
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r36 | |||
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r1091 | def hash(text, p1, p2): | ||
"""generate a hash from the given text and its parent hashes | ||||
This hash combines both the current file contents and its history | ||||
in a manner that makes it easy to distinguish nodes with the same | ||||
content in the revision graph. | ||||
""" | ||||
l = [p1, p2] | ||||
l.sort() | ||||
s = sha.new(l[0]) | ||||
s.update(l[1]) | ||||
s.update(text) | ||||
return s.digest() | ||||
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r0 | def compress(text): | ||
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r1083 | """ generate a possibly-compressed representation of text """ | ||
|
r1533 | if not text: return ("", text) | ||
|
r112 | if len(text) < 44: | ||
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r1533 | if text[0] == '\0': return ("", text) | ||
return ('u', text) | ||||
|
r112 | bin = zlib.compress(text) | ||
if len(bin) > len(text): | ||||
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r1533 | if text[0] == '\0': return ("", text) | ||
return ('u', text) | ||||
return ("", bin) | ||||
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r0 | |||
def decompress(bin): | ||||
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r1083 | """ decompress the given input """ | ||
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r112 | if not bin: return bin | ||
t = bin[0] | ||||
if t == '\0': return bin | ||||
if t == 'x': return zlib.decompress(bin) | ||||
if t == 'u': return bin[1:] | ||||
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r1402 | raise RevlogError(_("unknown compression type %s") % t) | ||
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r0 | |||
indexformat = ">4l20s20s20s" | ||||
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r1559 | class lazyparser(object): | ||
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r1083 | """ | ||
this class avoids the need to parse the entirety of large indices | ||||
By default we parse and load 1000 entries at a time. | ||||
If no position is specified, we load the whole index, and replace | ||||
the lazy objects in revlog with the underlying objects for | ||||
efficiency in cases where we look at most of the nodes. | ||||
""" | ||||
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r323 | def __init__(self, data, revlog): | ||
|
r76 | self.data = data | ||
self.s = struct.calcsize(indexformat) | ||||
self.l = len(data)/self.s | ||||
self.index = [None] * self.l | ||||
self.map = {nullid: -1} | ||||
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r323 | self.all = 0 | ||
self.revlog = revlog | ||||
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r76 | |||
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r1535 | def trunc(self, pos): | ||
self.l = pos/self.s | ||||
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r323 | def load(self, pos=None): | ||
if self.all: return | ||||
if pos is not None: | ||||
block = pos / 1000 | ||||
i = block * 1000 | ||||
end = min(self.l, i + 1000) | ||||
else: | ||||
self.all = 1 | ||||
i = 0 | ||||
end = self.l | ||||
self.revlog.index = self.index | ||||
self.revlog.nodemap = self.map | ||||
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r515 | |||
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r76 | while i < end: | ||
d = self.data[i * self.s: (i + 1) * self.s] | ||||
e = struct.unpack(indexformat, d) | ||||
self.index[i] = e | ||||
self.map[e[6]] = i | ||||
i += 1 | ||||
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r515 | |||
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r1559 | class lazyindex(object): | ||
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r1083 | """a lazy version of the index array""" | ||
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r76 | def __init__(self, parser): | ||
self.p = parser | ||||
def __len__(self): | ||||
return len(self.p.index) | ||||
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r115 | def load(self, pos): | ||
|
r1403 | if pos < 0: | ||
pos += len(self.p.index) | ||||
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r115 | self.p.load(pos) | ||
return self.p.index[pos] | ||||
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r76 | def __getitem__(self, pos): | ||
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r115 | return self.p.index[pos] or self.load(pos) | ||
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r1535 | def __delitem__(self, pos): | ||
del self.p.index[pos] | ||||
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r76 | def append(self, e): | ||
self.p.index.append(e) | ||||
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r1535 | def trunc(self, pos): | ||
self.p.trunc(pos) | ||||
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r515 | |||
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r1559 | class lazymap(object): | ||
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r1083 | """a lazy version of the node map""" | ||
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r76 | def __init__(self, parser): | ||
self.p = parser | ||||
def load(self, key): | ||||
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r323 | if self.p.all: return | ||
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r76 | n = self.p.data.find(key) | ||
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r1214 | if n < 0: | ||
raise KeyError(key) | ||||
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r76 | pos = n / self.p.s | ||
self.p.load(pos) | ||||
def __contains__(self, key): | ||||
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r323 | self.p.load() | ||
return key in self.p.map | ||||
|
r97 | def __iter__(self): | ||
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r469 | yield nullid | ||
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r97 | for i in xrange(self.p.l): | ||
try: | ||||
yield self.p.index[i][6] | ||||
except: | ||||
self.p.load(i) | ||||
yield self.p.index[i][6] | ||||
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r76 | def __getitem__(self, key): | ||
try: | ||||
return self.p.map[key] | ||||
except KeyError: | ||||
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r86 | try: | ||
self.load(key) | ||||
return self.p.map[key] | ||||
except KeyError: | ||||
raise KeyError("node " + hex(key)) | ||||
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r76 | def __setitem__(self, key, val): | ||
self.p.map[key] = val | ||||
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r1535 | def __delitem__(self, key): | ||
del self.p.map[key] | ||||
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r76 | |||
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r1073 | class RevlogError(Exception): pass | ||
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r1559 | class revlog(object): | ||
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r1083 | """ | ||
the underlying revision storage object | ||||
A revlog consists of two parts, an index and the revision data. | ||||
The index is a file with a fixed record size containing | ||||
information on each revision, includings its nodeid (hash), the | ||||
nodeids of its parents, the position and offset of its data within | ||||
the data file, and the revision it's based on. Finally, each entry | ||||
contains a linkrev entry that can serve as a pointer to external | ||||
data. | ||||
The revision data itself is a linear collection of data chunks. | ||||
Each chunk represents a revision and is usually represented as a | ||||
delta against the previous chunk. To bound lookup time, runs of | ||||
deltas are limited to about 2 times the length of the original | ||||
version data. This makes retrieval of a version proportional to | ||||
its size, or O(1) relative to the number of revisions. | ||||
Both pieces of the revlog are written to in an append-only | ||||
fashion, which means we never need to rewrite a file to insert or | ||||
remove data, and can use some simple techniques to avoid the need | ||||
for locking while reading. | ||||
""" | ||||
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r0 | def __init__(self, opener, indexfile, datafile): | ||
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r1083 | """ | ||
create a revlog object | ||||
opener is a function that abstracts the file opening operation | ||||
and can be used to implement COW semantics or the like. | ||||
""" | ||||
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r0 | self.indexfile = indexfile | ||
self.datafile = datafile | ||||
self.opener = opener | ||||
self.cache = None | ||||
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r1598 | self.chunkcache = None | ||
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r116 | |||
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r0 | try: | ||
i = self.opener(self.indexfile).read() | ||||
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r1322 | except IOError, inst: | ||
if inst.errno != errno.ENOENT: | ||||
raise | ||||
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r76 | i = "" | ||
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r116 | |||
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r1660 | if i and i[:4] != "\0\0\0\0": | ||
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r1659 | raise RevlogError(_("incompatible revlog signature on %s") % | ||
self.indexfile) | ||||
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r116 | if len(i) > 10000: | ||
# big index, let's parse it on demand | ||||
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r323 | parser = lazyparser(i, self) | ||
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r116 | self.index = lazyindex(parser) | ||
self.nodemap = lazymap(parser) | ||||
else: | ||||
s = struct.calcsize(indexformat) | ||||
l = len(i) / s | ||||
self.index = [None] * l | ||||
m = [None] * l | ||||
n = 0 | ||||
for f in xrange(0, len(i), s): | ||||
# offset, size, base, linkrev, p1, p2, nodeid | ||||
e = struct.unpack(indexformat, i[f:f + s]) | ||||
m[n] = (e[6], n) | ||||
self.index[n] = e | ||||
n += 1 | ||||
self.nodemap = dict(m) | ||||
self.nodemap[nullid] = -1 | ||||
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r0 | |||
def tip(self): return self.node(len(self.index) - 1) | ||||
def count(self): return len(self.index) | ||||
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r26 | def node(self, rev): return (rev < 0) and nullid or self.index[rev][6] | ||
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r1201 | def rev(self, node): | ||
try: | ||||
return self.nodemap[node] | ||||
except KeyError: | ||||
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r1402 | raise RevlogError(_('%s: no node %s') % (self.indexfile, hex(node))) | ||
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r1201 | def linkrev(self, node): return self.index[self.rev(node)][3] | ||
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r2 | def parents(self, node): | ||
if node == nullid: return (nullid, nullid) | ||||
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r1201 | return self.index[self.rev(node)][4:6] | ||
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r0 | |||
def start(self, rev): return self.index[rev][0] | ||||
def length(self, rev): return self.index[rev][1] | ||||
def end(self, rev): return self.start(rev) + self.length(rev) | ||||
def base(self, rev): return self.index[rev][2] | ||||
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r1074 | def reachable(self, rev, stop=None): | ||
reachable = {} | ||||
visit = [rev] | ||||
reachable[rev] = 1 | ||||
if stop: | ||||
stopn = self.rev(stop) | ||||
else: | ||||
stopn = 0 | ||||
while visit: | ||||
n = visit.pop(0) | ||||
if n == stop: | ||||
continue | ||||
if n == nullid: | ||||
continue | ||||
for p in self.parents(n): | ||||
if self.rev(p) < stopn: | ||||
continue | ||||
if p not in reachable: | ||||
reachable[p] = 1 | ||||
visit.append(p) | ||||
return reachable | ||||
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r1457 | def nodesbetween(self, roots=None, heads=None): | ||
"""Return a tuple containing three elements. Elements 1 and 2 contain | ||||
a final list bases and heads after all the unreachable ones have been | ||||
pruned. Element 0 contains a topologically sorted list of all | ||||
nodes that satisfy these constraints: | ||||
1. All nodes must be descended from a node in roots (the nodes on | ||||
roots are considered descended from themselves). | ||||
2. All nodes must also be ancestors of a node in heads (the nodes in | ||||
heads are considered to be their own ancestors). | ||||
If roots is unspecified, nullid is assumed as the only root. | ||||
If heads is unspecified, it is taken to be the output of the | ||||
heads method (i.e. a list of all nodes in the repository that | ||||
have no children).""" | ||||
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r1463 | nonodes = ([], [], []) | ||
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r1457 | if roots is not None: | ||
roots = list(roots) | ||||
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r1463 | if not roots: | ||
return nonodes | ||||
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r1457 | lowestrev = min([self.rev(n) for n in roots]) | ||
else: | ||||
roots = [nullid] # Everybody's a descendent of nullid | ||||
lowestrev = -1 | ||||
if (lowestrev == -1) and (heads is None): | ||||
# We want _all_ the nodes! | ||||
return ([self.node(r) for r in xrange(0, self.count())], | ||||
[nullid], list(self.heads())) | ||||
if heads is None: | ||||
# All nodes are ancestors, so the latest ancestor is the last | ||||
# node. | ||||
highestrev = self.count() - 1 | ||||
# Set ancestors to None to signal that every node is an ancestor. | ||||
ancestors = None | ||||
# Set heads to an empty dictionary for later discovery of heads | ||||
heads = {} | ||||
else: | ||||
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r1463 | heads = list(heads) | ||
if not heads: | ||||
return nonodes | ||||
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r1457 | ancestors = {} | ||
# Start at the top and keep marking parents until we're done. | ||||
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r1463 | nodestotag = heads[:] | ||
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r1457 | # Turn heads into a dictionary so we can remove 'fake' heads. | ||
# Also, later we will be using it to filter out the heads we can't | ||||
# find from roots. | ||||
heads = dict.fromkeys(heads, 0) | ||||
# Remember where the top was so we can use it as a limit later. | ||||
highestrev = max([self.rev(n) for n in nodestotag]) | ||||
while nodestotag: | ||||
# grab a node to tag | ||||
n = nodestotag.pop() | ||||
# Never tag nullid | ||||
if n == nullid: | ||||
continue | ||||
# A node's revision number represents its place in a | ||||
# topologically sorted list of nodes. | ||||
r = self.rev(n) | ||||
if r >= lowestrev: | ||||
if n not in ancestors: | ||||
# If we are possibly a descendent of one of the roots | ||||
# and we haven't already been marked as an ancestor | ||||
ancestors[n] = 1 # Mark as ancestor | ||||
# Add non-nullid parents to list of nodes to tag. | ||||
nodestotag.extend([p for p in self.parents(n) if | ||||
p != nullid]) | ||||
elif n in heads: # We've seen it before, is it a fake head? | ||||
# So it is, real heads should not be the ancestors of | ||||
# any other heads. | ||||
heads.pop(n) | ||||
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r1459 | if not ancestors: | ||
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r1463 | return nonodes | ||
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r1457 | # Now that we have our set of ancestors, we want to remove any | ||
# roots that are not ancestors. | ||||
# If one of the roots was nullid, everything is included anyway. | ||||
if lowestrev > -1: | ||||
# But, since we weren't, let's recompute the lowest rev to not | ||||
# include roots that aren't ancestors. | ||||
# Filter out roots that aren't ancestors of heads | ||||
roots = [n for n in roots if n in ancestors] | ||||
# Recompute the lowest revision | ||||
if roots: | ||||
lowestrev = min([self.rev(n) for n in roots]) | ||||
else: | ||||
# No more roots? Return empty list | ||||
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r1463 | return nonodes | ||
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r1457 | else: | ||
# We are descending from nullid, and don't need to care about | ||||
# any other roots. | ||||
lowestrev = -1 | ||||
roots = [nullid] | ||||
# Transform our roots list into a 'set' (i.e. a dictionary where the | ||||
# values don't matter. | ||||
descendents = dict.fromkeys(roots, 1) | ||||
# Also, keep the original roots so we can filter out roots that aren't | ||||
# 'real' roots (i.e. are descended from other roots). | ||||
roots = descendents.copy() | ||||
# Our topologically sorted list of output nodes. | ||||
orderedout = [] | ||||
# Don't start at nullid since we don't want nullid in our output list, | ||||
# and if nullid shows up in descedents, empty parents will look like | ||||
# they're descendents. | ||||
for r in xrange(max(lowestrev, 0), highestrev + 1): | ||||
n = self.node(r) | ||||
isdescendent = False | ||||
if lowestrev == -1: # Everybody is a descendent of nullid | ||||
isdescendent = True | ||||
elif n in descendents: | ||||
# n is already a descendent | ||||
isdescendent = True | ||||
# This check only needs to be done here because all the roots | ||||
# will start being marked is descendents before the loop. | ||||
if n in roots: | ||||
# If n was a root, check if it's a 'real' root. | ||||
p = tuple(self.parents(n)) | ||||
# If any of its parents are descendents, it's not a root. | ||||
if (p[0] in descendents) or (p[1] in descendents): | ||||
roots.pop(n) | ||||
else: | ||||
p = tuple(self.parents(n)) | ||||
# A node is a descendent if either of its parents are | ||||
# descendents. (We seeded the dependents list with the roots | ||||
# up there, remember?) | ||||
if (p[0] in descendents) or (p[1] in descendents): | ||||
descendents[n] = 1 | ||||
isdescendent = True | ||||
if isdescendent and ((ancestors is None) or (n in ancestors)): | ||||
# Only include nodes that are both descendents and ancestors. | ||||
orderedout.append(n) | ||||
if (ancestors is not None) and (n in heads): | ||||
# We're trying to figure out which heads are reachable | ||||
# from roots. | ||||
# Mark this head as having been reached | ||||
heads[n] = 1 | ||||
elif ancestors is None: | ||||
# Otherwise, we're trying to discover the heads. | ||||
# Assume this is a head because if it isn't, the next step | ||||
# will eventually remove it. | ||||
heads[n] = 1 | ||||
# But, obviously its parents aren't. | ||||
for p in self.parents(n): | ||||
heads.pop(p, None) | ||||
heads = [n for n in heads.iterkeys() if heads[n] != 0] | ||||
roots = roots.keys() | ||||
assert orderedout | ||||
assert roots | ||||
assert heads | ||||
return (orderedout, roots, heads) | ||||
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r1551 | def heads(self, start=None): | ||
|
r1550 | """return the list of all nodes that have no children | ||
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r1551 | |||
if start is specified, only heads that are descendants of | ||||
start will be returned | ||||
""" | ||||
if start is None: | ||||
start = nullid | ||||
|
r1550 | reachable = {start: 1} | ||
heads = {start: 1} | ||||
startrev = self.rev(start) | ||||
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r1083 | |||
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r1550 | for r in xrange(startrev + 1, self.count()): | ||
|
r221 | n = self.node(r) | ||
for pn in self.parents(n): | ||||
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r1550 | if pn in reachable: | ||
reachable[n] = 1 | ||||
heads[n] = 1 | ||||
if pn in heads: | ||||
del heads[pn] | ||||
return heads.keys() | ||||
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r370 | |||
def children(self, node): | ||||
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r1083 | """find the children of a given node""" | ||
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r370 | c = [] | ||
p = self.rev(node) | ||||
for r in range(p + 1, self.count()): | ||||
n = self.node(r) | ||||
for pn in self.parents(n): | ||||
|
r854 | if pn == node: | ||
c.append(n) | ||||
|
r370 | continue | ||
elif pn == nullid: | ||||
continue | ||||
return c | ||||
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r515 | |||
|
r36 | def lookup(self, id): | ||
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r1083 | """locate a node based on revision number or subset of hex nodeid""" | ||
|
r36 | try: | ||
rev = int(id) | ||||
|
r469 | if str(rev) != id: raise ValueError | ||
if rev < 0: rev = self.count() + rev | ||||
|
r476 | if rev < 0 or rev >= self.count(): raise ValueError | ||
|
r36 | return self.node(rev) | ||
|
r469 | except (ValueError, OverflowError): | ||
|
r36 | c = [] | ||
for n in self.nodemap: | ||||
|
r469 | if hex(n).startswith(id): | ||
|
r36 | c.append(n) | ||
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r1402 | if len(c) > 1: raise RevlogError(_("Ambiguous identifier")) | ||
if len(c) < 1: raise RevlogError(_("No match found")) | ||||
|
r36 | return c[0] | ||
|
r515 | |||
|
r36 | return None | ||
|
r0 | def diff(self, a, b): | ||
|
r1083 | """return a delta between two revisions""" | ||
|
r0 | return mdiff.textdiff(a, b) | ||
|
r73 | def patches(self, t, pl): | ||
|
r1083 | """apply a list of patches to a string""" | ||
|
r73 | return mdiff.patches(t, pl) | ||
|
r1598 | def chunk(self, rev): | ||
start, length = self.start(rev), self.length(rev) | ||||
end = start + length | ||||
def loadcache(): | ||||
cache_length = max(4096 * 1024, length) # 4Mo | ||||
df = self.opener(self.datafile) | ||||
df.seek(start) | ||||
self.chunkcache = (start, df.read(cache_length)) | ||||
if not self.chunkcache: | ||||
loadcache() | ||||
cache_start = self.chunkcache[0] | ||||
cache_end = cache_start + len(self.chunkcache[1]) | ||||
if start >= cache_start and end <= cache_end: | ||||
# it is cached | ||||
offset = start - cache_start | ||||
else: | ||||
loadcache() | ||||
offset = 0 | ||||
#def checkchunk(): | ||||
# df = self.opener(self.datafile) | ||||
# df.seek(start) | ||||
# return df.read(length) | ||||
#assert s == checkchunk() | ||||
return decompress(self.chunkcache[1][offset:offset + length]) | ||||
|
r119 | def delta(self, node): | ||
|
r1083 | """return or calculate a delta between a node and its predecessor""" | ||
|
r119 | r = self.rev(node) | ||
b = self.base(r) | ||||
if r == b: | ||||
return self.diff(self.revision(self.node(r - 1)), | ||||
self.revision(node)) | ||||
else: | ||||
|
r1598 | return self.chunk(r) | ||
|
r119 | |||
|
r0 | def revision(self, node): | ||
|
r1083 | """return an uncompressed revision of a given""" | ||
|
r36 | if node == nullid: return "" | ||
|
r0 | if self.cache and self.cache[0] == node: return self.cache[2] | ||
|
r1083 | # look up what we need to read | ||
|
r0 | text = None | ||
rev = self.rev(node) | ||||
|
r1598 | base = self.base(rev) | ||
|
r0 | |||
|
r1083 | # do we have useful data cached? | ||
|
r0 | if self.cache and self.cache[1] >= base and self.cache[1] < rev: | ||
base = self.cache[1] | ||||
text = self.cache[2] | ||||
|
r1598 | else: | ||
text = self.chunk(base) | ||||
|
r0 | |||
|
r71 | bins = [] | ||
|
r64 | for r in xrange(base + 1, rev + 1): | ||
|
r1598 | bins.append(self.chunk(r)) | ||
|
r0 | |||
|
r71 | text = mdiff.patches(text, bins) | ||
|
r1598 | p1, p2 = self.parents(node) | ||
|
r26 | if node != hash(text, p1, p2): | ||
|
r1402 | raise RevlogError(_("integrity check failed on %s:%d") | ||
|
r98 | % (self.datafile, rev)) | ||
|
r0 | |||
self.cache = (node, rev, text) | ||||
|
r515 | return text | ||
|
r0 | |||
|
r644 | def addrevision(self, text, transaction, link, p1=None, p2=None, d=None): | ||
|
r1083 | """add a revision to the log | ||
text - the revision data to add | ||||
transaction - the transaction object used for rollback | ||||
link - the linkrev data to add | ||||
p1, p2 - the parent nodeids of the revision | ||||
d - an optional precomputed delta | ||||
""" | ||||
|
r0 | if text is None: text = "" | ||
if p1 is None: p1 = self.tip() | ||||
if p2 is None: p2 = nullid | ||||
node = hash(text, p1, p2) | ||||
|
r301 | if node in self.nodemap: | ||
return node | ||||
|
r0 | n = self.count() | ||
t = n - 1 | ||||
if n: | ||||
|
r64 | base = self.base(t) | ||
start = self.start(base) | ||||
|
r0 | end = self.end(t) | ||
|
r644 | if not d: | ||
prev = self.revision(self.tip()) | ||||
|
r1533 | d = self.diff(prev, str(text)) | ||
|
r98 | data = compress(d) | ||
|
r1533 | l = len(data[1]) + len(data[0]) | ||
dist = end - start + l | ||||
|
r0 | |||
# full versions are inserted when the needed deltas | ||||
# become comparable to the uncompressed text | ||||
|
r64 | if not n or dist > len(text) * 2: | ||
|
r0 | data = compress(text) | ||
|
r1533 | l = len(data[1]) + len(data[0]) | ||
|
r0 | base = n | ||
else: | ||||
base = self.base(t) | ||||
offset = 0 | ||||
if t >= 0: | ||||
offset = self.end(t) | ||||
|
r1533 | e = (offset, l, base, link, p1, p2, node) | ||
|
r515 | |||
|
r0 | self.index.append(e) | ||
self.nodemap[node] = n | ||||
entry = struct.pack(indexformat, *e) | ||||
|
r26 | transaction.add(self.datafile, e[0]) | ||
|
r1533 | f = self.opener(self.datafile, "a") | ||
if data[0]: | ||||
f.write(data[0]) | ||||
f.write(data[1]) | ||||
|
r41 | transaction.add(self.indexfile, n * len(entry)) | ||
|
r0 | self.opener(self.indexfile, "a").write(entry) | ||
self.cache = (node, n, text) | ||||
return node | ||||
def ancestor(self, a, b): | ||||
|
r1083 | """calculate the least common ancestor of nodes a and b""" | ||
|
r147 | # calculate the distance of every node from root | ||
dist = {nullid: 0} | ||||
for i in xrange(self.count()): | ||||
n = self.node(i) | ||||
p1, p2 = self.parents(n) | ||||
dist[n] = max(dist[p1], dist[p2]) + 1 | ||||
|
r515 | |||
|
r147 | # traverse ancestors in order of decreasing distance from root | ||
def ancestors(node): | ||||
# we store negative distances because heap returns smallest member | ||||
h = [(-dist[node], node)] | ||||
seen = {} | ||||
earliest = self.count() | ||||
while h: | ||||
d, n = heapq.heappop(h) | ||||
if n not in seen: | ||||
seen[n] = 1 | ||||
|
r381 | r = self.rev(n) | ||
|
r1351 | yield (-d, n) | ||
|
r147 | for p in self.parents(n): | ||
heapq.heappush(h, (-dist[p], p)) | ||||
|
r45 | |||
|
r1351 | def generations(node): | ||
sg, s = None, {} | ||||
for g,n in ancestors(node): | ||||
if g != sg: | ||||
if sg: | ||||
yield sg, s | ||||
sg, s = g, {n:1} | ||||
else: | ||||
s[n] = 1 | ||||
yield sg, s | ||||
x = generations(a) | ||||
y = generations(b) | ||||
gx = x.next() | ||||
gy = y.next() | ||||
|
r45 | |||
|
r147 | # increment each ancestor list until it is closer to root than | ||
# the other, or they match | ||||
while 1: | ||||
|
r1351 | #print "ancestor gen %s %s" % (gx[0], gy[0]) | ||
if gx[0] == gy[0]: | ||||
# find the intersection | ||||
i = [ n for n in gx[1] if n in gy[1] ] | ||||
if i: | ||||
return i[0] | ||||
else: | ||||
#print "next" | ||||
gy = y.next() | ||||
gx = x.next() | ||||
elif gx[0] < gy[0]: | ||||
#print "next y" | ||||
gy = y.next() | ||||
else: | ||||
#print "next x" | ||||
gx = x.next() | ||||
|
r0 | |||
|
r1598 | def group(self, nodelist, lookup, infocollect=None): | ||
|
r1083 | """calculate a delta group | ||
|
r46 | |||
|
r1083 | Given a list of changeset revs, return a set of deltas and | ||
metadata corresponding to nodes. the first delta is | ||||
parent(nodes[0]) -> nodes[0] the receiver is guaranteed to | ||||
have this parent as it has all history before these | ||||
changesets. parent is parent[0] | ||||
""" | ||||
|
r1458 | revs = [self.rev(n) for n in nodelist] | ||
|
r46 | |||
# if we don't have any revisions touched by these changesets, bail | ||||
|
r192 | if not revs: | ||
yield struct.pack(">l", 0) | ||||
return | ||||
|
r46 | |||
# add the parent of the first rev | ||||
p = self.parents(self.node(revs[0]))[0] | ||||
revs.insert(0, self.rev(p)) | ||||
# helper to reconstruct intermediate versions | ||||
def construct(text, base, rev): | ||||
|
r1598 | bins = [self.chunk(r) for r in xrange(base + 1, rev + 1)] | ||
|
r71 | return mdiff.patches(text, bins) | ||
|
r46 | |||
# build deltas | ||||
|
r71 | for d in xrange(0, len(revs) - 1): | ||
|
r46 | a, b = revs[d], revs[d + 1] | ||
|
r1598 | na = self.node(a) | ||
nb = self.node(b) | ||||
|
r192 | |||
|
r1458 | if infocollect is not None: | ||
|
r1598 | infocollect(nb) | ||
|
r1458 | |||
|
r192 | # do we need to construct a new delta? | ||
|
r46 | if a + 1 != b or self.base(b) == b: | ||
|
r1598 | ta = self.revision(na) | ||
tb = self.revision(nb) | ||||
|
r46 | d = self.diff(ta, tb) | ||
else: | ||||
|
r1598 | d = self.chunk(b) | ||
|
r46 | |||
|
r1598 | p = self.parents(nb) | ||
meta = nb + p[0] + p[1] + lookup(nb) | ||||
|
r46 | l = struct.pack(">l", len(meta) + len(d) + 4) | ||
|
r192 | yield l | ||
yield meta | ||||
yield d | ||||
|
r46 | |||
|
r192 | yield struct.pack(">l", 0) | ||
|
r1062 | def addgroup(self, revs, linkmapper, transaction, unique=0): | ||
|
r1083 | """ | ||
add a delta group | ||||
|
r46 | |||
|
r1083 | given a set of deltas, add them to the revision log. the | ||
first delta is against its parent, which should be in our | ||||
log, the rest are against the previous delta. | ||||
""" | ||||
#track the base of the current delta log | ||||
|
r46 | r = self.count() | ||
t = r - 1 | ||||
|
r192 | node = nullid | ||
|
r515 | |||
|
r655 | base = prev = -1 | ||
|
r653 | start = end = measure = 0 | ||
|
r46 | if r: | ||
start = self.start(self.base(t)) | ||||
end = self.end(t) | ||||
measure = self.length(self.base(t)) | ||||
base = self.base(t) | ||||
prev = self.tip() | ||||
transaction.add(self.datafile, end) | ||||
transaction.add(self.indexfile, r * struct.calcsize(indexformat)) | ||||
dfh = self.opener(self.datafile, "a") | ||||
ifh = self.opener(self.indexfile, "a") | ||||
# loop through our set of deltas | ||||
|
r192 | chain = None | ||
for chunk in revs: | ||||
node, p1, p2, cs = struct.unpack("20s20s20s20s", chunk[:80]) | ||||
|
r94 | link = linkmapper(cs) | ||
|
r77 | if node in self.nodemap: | ||
|
r224 | # this can happen if two branches make the same change | ||
|
r1218 | # if unique: | ||
|
r1402 | # raise RevlogError(_("already have %s") % hex(node[:4])) | ||
|
r653 | chain = node | ||
|
r224 | continue | ||
|
r192 | delta = chunk[80:] | ||
|
r1509 | for p in (p1, p2): | ||
if not p in self.nodemap: | ||||
raise RevlogError(_("unknown parent %s") % short(p1)) | ||||
|
r192 | if not chain: | ||
# retrieve the parent revision of the delta chain | ||||
chain = p1 | ||||
if not chain in self.nodemap: | ||||
|
r1402 | raise RevlogError(_("unknown base %s") % short(chain[:4])) | ||
|
r46 | |||
# full versions are inserted when the needed deltas become | ||||
# comparable to the uncompressed text or when the previous | ||||
# version is not the one we have a delta against. We use | ||||
# the size of the previous full rev as a proxy for the | ||||
# current size. | ||||
if chain == prev: | ||||
|
r1533 | tempd = compress(delta) | ||
cdelta = tempd[0] + tempd[1] | ||||
|
r46 | |||
if chain != prev or (end - start + len(cdelta)) > measure * 2: | ||||
# flush our writes here so we can read it in revision | ||||
dfh.flush() | ||||
ifh.flush() | ||||
|
r65 | text = self.revision(chain) | ||
|
r73 | text = self.patches(text, [delta]) | ||
|
r46 | chk = self.addrevision(text, transaction, link, p1, p2) | ||
if chk != node: | ||||
|
r1402 | raise RevlogError(_("consistency error adding group")) | ||
|
r46 | measure = len(text) | ||
else: | ||||
e = (end, len(cdelta), self.base(t), link, p1, p2, node) | ||||
self.index.append(e) | ||||
self.nodemap[node] = r | ||||
dfh.write(cdelta) | ||||
ifh.write(struct.pack(indexformat, *e)) | ||||
|
r65 | t, r, chain, prev = r, r + 1, node, node | ||
|
r46 | start = self.start(self.base(t)) | ||
end = self.end(t) | ||||
dfh.close() | ||||
ifh.close() | ||||
return node | ||||
|
r1493 | |||
|
r1535 | def strip(self, rev, minlink): | ||
if self.count() == 0 or rev >= self.count(): | ||||
return | ||||
# When stripping away a revision, we need to make sure it | ||||
# does not actually belong to an older changeset. | ||||
# The minlink parameter defines the oldest revision | ||||
# we're allowed to strip away. | ||||
while minlink > self.index[rev][3]: | ||||
rev += 1 | ||||
if rev >= self.count(): | ||||
return | ||||
# first truncate the files on disk | ||||
end = self.start(rev) | ||||
self.opener(self.datafile, "a").truncate(end) | ||||
end = rev * struct.calcsize(indexformat) | ||||
self.opener(self.indexfile, "a").truncate(end) | ||||
# then reset internal state in memory to forget those revisions | ||||
self.cache = None | ||||
for p in self.index[rev:]: | ||||
del self.nodemap[p[6]] | ||||
del self.index[rev:] | ||||
# truncating the lazyindex also truncates the lazymap. | ||||
if isinstance(self.index, lazyindex): | ||||
self.index.trunc(end) | ||||
|
r1493 | def checksize(self): | ||
expected = 0 | ||||
if self.count(): | ||||
expected = self.end(self.count() - 1) | ||||
|
r1494 | try: | ||
f = self.opener(self.datafile) | ||||
f.seek(0, 2) | ||||
actual = f.tell() | ||||
return expected - actual | ||||
except IOError, inst: | ||||
if inst.errno == errno.ENOENT: | ||||
return 0 | ||||
raise | ||||