Mercurial > hg
view mercurial/revlog.py @ 40599:9eeda7199181
manifest: make sure there's a filename before bothering to look for newline
There's no valid manifest that would have no characters before the NUL byte on
a line, and this fixes some erratic timeouts in the fuzzer.
Differential Revision: https://phab.mercurial-scm.org/D5256
| author | Augie Fackler <augie@google.com> |
|---|---|
| date | Mon, 12 Nov 2018 20:35:22 -0500 |
| parents | 4fe63b573791 |
| children | 39369475445c |
line wrap: on
line source
# revlog.py - storage back-end 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. """Storage back-end for Mercurial. This provides efficient delta storage with O(1) retrieve and append and O(changes) merge between branches. """ from __future__ import absolute_import import collections import contextlib import errno import os import struct import zlib # import stuff from node for others to import from revlog from .node import ( bin, hex, nullhex, nullid, nullrev, short, wdirfilenodeids, wdirhex, wdirid, wdirrev, ) from .i18n import _ from .revlogutils.constants import ( FLAG_GENERALDELTA, FLAG_INLINE_DATA, REVIDX_DEFAULT_FLAGS, REVIDX_ELLIPSIS, REVIDX_EXTSTORED, REVIDX_FLAGS_ORDER, REVIDX_ISCENSORED, REVIDX_KNOWN_FLAGS, REVIDX_RAWTEXT_CHANGING_FLAGS, REVLOGV0, REVLOGV1, REVLOGV1_FLAGS, REVLOGV2, REVLOGV2_FLAGS, REVLOG_DEFAULT_FLAGS, REVLOG_DEFAULT_FORMAT, REVLOG_DEFAULT_VERSION, ) from .thirdparty import ( attr, ) from . import ( ancestor, dagop, error, mdiff, policy, pycompat, repository, templatefilters, util, ) from .revlogutils import ( deltas as deltautil, ) from .utils import ( interfaceutil, storageutil, stringutil, ) # blanked usage of all the name to prevent pyflakes constraints # We need these name available in the module for extensions. REVLOGV0 REVLOGV1 REVLOGV2 FLAG_INLINE_DATA FLAG_GENERALDELTA REVLOG_DEFAULT_FLAGS REVLOG_DEFAULT_FORMAT REVLOG_DEFAULT_VERSION REVLOGV1_FLAGS REVLOGV2_FLAGS REVIDX_ISCENSORED REVIDX_ELLIPSIS REVIDX_EXTSTORED REVIDX_DEFAULT_FLAGS REVIDX_FLAGS_ORDER REVIDX_KNOWN_FLAGS REVIDX_RAWTEXT_CHANGING_FLAGS parsers = policy.importmod(r'parsers') # Aliased for performance. _zlibdecompress = zlib.decompress # max size of revlog with inline data _maxinline = 131072 _chunksize = 1048576 # Store flag processors (cf. 'addflagprocessor()' to register) _flagprocessors = { REVIDX_ISCENSORED: None, } # Flag processors for REVIDX_ELLIPSIS. def ellipsisreadprocessor(rl, text): return text, False def ellipsiswriteprocessor(rl, text): return text, False def ellipsisrawprocessor(rl, text): return False ellipsisprocessor = ( ellipsisreadprocessor, ellipsiswriteprocessor, ellipsisrawprocessor, ) def addflagprocessor(flag, processor): """Register a flag processor on a revision data flag. Invariant: - Flags need to be defined in REVIDX_KNOWN_FLAGS and REVIDX_FLAGS_ORDER, and REVIDX_RAWTEXT_CHANGING_FLAGS if they can alter rawtext. - Only one flag processor can be registered on a specific flag. - flagprocessors must be 3-tuples of functions (read, write, raw) with the following signatures: - (read) f(self, rawtext) -> text, bool - (write) f(self, text) -> rawtext, bool - (raw) f(self, rawtext) -> bool "text" is presented to the user. "rawtext" is stored in revlog data, not directly visible to the user. The boolean returned by these transforms is used to determine whether the returned text can be used for hash integrity checking. For example, if "write" returns False, then "text" is used to generate hash. If "write" returns True, that basically means "rawtext" returned by "write" should be used to generate hash. Usually, "write" and "read" return different booleans. And "raw" returns a same boolean as "write". Note: The 'raw' transform is used for changegroup generation and in some debug commands. In this case the transform only indicates whether the contents can be used for hash integrity checks. """ _insertflagprocessor(flag, processor, _flagprocessors) def _insertflagprocessor(flag, processor, flagprocessors): if not flag & REVIDX_KNOWN_FLAGS: msg = _("cannot register processor on unknown flag '%#x'.") % (flag) raise error.ProgrammingError(msg) if flag not in REVIDX_FLAGS_ORDER: msg = _("flag '%#x' undefined in REVIDX_FLAGS_ORDER.") % (flag) raise error.ProgrammingError(msg) if flag in flagprocessors: msg = _("cannot register multiple processors on flag '%#x'.") % (flag) raise error.Abort(msg) flagprocessors[flag] = processor def getoffset(q): return int(q >> 16) def gettype(q): return int(q & 0xFFFF) def offset_type(offset, type): if (type & ~REVIDX_KNOWN_FLAGS) != 0: raise ValueError('unknown revlog index flags') return int(int(offset) << 16 | type) @attr.s(slots=True, frozen=True) class _revisioninfo(object): """Information about a revision that allows building its fulltext node: expected hash of the revision p1, p2: parent revs of the revision btext: built text cache consisting of a one-element list cachedelta: (baserev, uncompressed_delta) or None flags: flags associated to the revision storage One of btext[0] or cachedelta must be set. """ node = attr.ib() p1 = attr.ib() p2 = attr.ib() btext = attr.ib() textlen = attr.ib() cachedelta = attr.ib() flags = attr.ib() @interfaceutil.implementer(repository.irevisiondelta) @attr.s(slots=True) class revlogrevisiondelta(object): node = attr.ib() p1node = attr.ib() p2node = attr.ib() basenode = attr.ib() flags = attr.ib() baserevisionsize = attr.ib() revision = attr.ib() delta = attr.ib() linknode = attr.ib(default=None) @interfaceutil.implementer(repository.iverifyproblem) @attr.s(frozen=True) class revlogproblem(object): warning = attr.ib(default=None) error = attr.ib(default=None) node = attr.ib(default=None) # index v0: # 4 bytes: offset # 4 bytes: compressed length # 4 bytes: base rev # 4 bytes: link rev # 20 bytes: parent 1 nodeid # 20 bytes: parent 2 nodeid # 20 bytes: nodeid indexformatv0 = struct.Struct(">4l20s20s20s") indexformatv0_pack = indexformatv0.pack indexformatv0_unpack = indexformatv0.unpack class revlogoldindex(list): def __getitem__(self, i): if i == -1: return (0, 0, 0, -1, -1, -1, -1, nullid) return list.__getitem__(self, i) class revlogoldio(object): def __init__(self): self.size = indexformatv0.size def parseindex(self, data, inline): s = self.size index = [] nodemap = {nullid: nullrev} n = off = 0 l = len(data) while off + s <= l: cur = data[off:off + s] off += s e = indexformatv0_unpack(cur) # transform to revlogv1 format e2 = (offset_type(e[0], 0), e[1], -1, e[2], e[3], nodemap.get(e[4], nullrev), nodemap.get(e[5], nullrev), e[6]) index.append(e2) nodemap[e[6]] = n n += 1 return revlogoldindex(index), nodemap, None def packentry(self, entry, node, version, rev): if gettype(entry[0]): raise error.RevlogError(_('index entry flags need revlog ' 'version 1')) e2 = (getoffset(entry[0]), entry[1], entry[3], entry[4], node(entry[5]), node(entry[6]), entry[7]) return indexformatv0_pack(*e2) # index ng: # 6 bytes: offset # 2 bytes: flags # 4 bytes: compressed length # 4 bytes: uncompressed length # 4 bytes: base rev # 4 bytes: link rev # 4 bytes: parent 1 rev # 4 bytes: parent 2 rev # 32 bytes: nodeid indexformatng = struct.Struct(">Qiiiiii20s12x") indexformatng_pack = indexformatng.pack versionformat = struct.Struct(">I") versionformat_pack = versionformat.pack versionformat_unpack = versionformat.unpack # corresponds to uncompressed length of indexformatng (2 gigs, 4-byte # signed integer) _maxentrysize = 0x7fffffff class revlogio(object): def __init__(self): self.size = indexformatng.size def parseindex(self, data, inline): # call the C implementation to parse the index data index, cache = parsers.parse_index2(data, inline) return index, getattr(index, 'nodemap', None), cache def packentry(self, entry, node, version, rev): p = indexformatng_pack(*entry) if rev == 0: p = versionformat_pack(version) + p[4:] return p class revlog(object): """ 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, including 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. If checkambig, indexfile is opened with checkambig=True at writing, to avoid file stat ambiguity. If mmaplargeindex is True, and an mmapindexthreshold is set, the index will be mmapped rather than read if it is larger than the configured threshold. If censorable is True, the revlog can have censored revisions. """ def __init__(self, opener, indexfile, datafile=None, checkambig=False, mmaplargeindex=False, censorable=False): """ 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. """ self.indexfile = indexfile self.datafile = datafile or (indexfile[:-2] + ".d") self.opener = opener # When True, indexfile is opened with checkambig=True at writing, to # avoid file stat ambiguity. self._checkambig = checkambig self._censorable = censorable # 3-tuple of (node, rev, text) for a raw revision. self._revisioncache = None # Maps rev to chain base rev. self._chainbasecache = util.lrucachedict(100) # 2-tuple of (offset, data) of raw data from the revlog at an offset. self._chunkcache = (0, '') # How much data to read and cache into the raw revlog data cache. self._chunkcachesize = 65536 self._maxchainlen = None self._deltabothparents = True self.index = [] # Mapping of partial identifiers to full nodes. self._pcache = {} # Mapping of revision integer to full node. self._nodecache = {nullid: nullrev} self._nodepos = None self._compengine = 'zlib' self._maxdeltachainspan = -1 self._withsparseread = False self._sparserevlog = False self._srdensitythreshold = 0.50 self._srmingapsize = 262144 # Make copy of flag processors so each revlog instance can support # custom flags. self._flagprocessors = dict(_flagprocessors) mmapindexthreshold = None v = REVLOG_DEFAULT_VERSION opts = getattr(opener, 'options', None) if opts is not None: if 'revlogv2' in opts: # version 2 revlogs always use generaldelta. v = REVLOGV2 | FLAG_GENERALDELTA | FLAG_INLINE_DATA elif 'revlogv1' in opts: if 'generaldelta' in opts: v |= FLAG_GENERALDELTA else: v = 0 if 'chunkcachesize' in opts: self._chunkcachesize = opts['chunkcachesize'] if 'maxchainlen' in opts: self._maxchainlen = opts['maxchainlen'] if 'deltabothparents' in opts: self._deltabothparents = opts['deltabothparents'] self._lazydeltabase = bool(opts.get('lazydeltabase', False)) if 'compengine' in opts: self._compengine = opts['compengine'] if 'maxdeltachainspan' in opts: self._maxdeltachainspan = opts['maxdeltachainspan'] if mmaplargeindex and 'mmapindexthreshold' in opts: mmapindexthreshold = opts['mmapindexthreshold'] self._sparserevlog = bool(opts.get('sparse-revlog', False)) withsparseread = bool(opts.get('with-sparse-read', False)) # sparse-revlog forces sparse-read self._withsparseread = self._sparserevlog or withsparseread if 'sparse-read-density-threshold' in opts: self._srdensitythreshold = opts['sparse-read-density-threshold'] if 'sparse-read-min-gap-size' in opts: self._srmingapsize = opts['sparse-read-min-gap-size'] if opts.get('enableellipsis'): self._flagprocessors[REVIDX_ELLIPSIS] = ellipsisprocessor # revlog v0 doesn't have flag processors for flag, processor in opts.get(b'flagprocessors', {}).iteritems(): _insertflagprocessor(flag, processor, self._flagprocessors) if self._chunkcachesize <= 0: raise error.RevlogError(_('revlog chunk cache size %r is not ' 'greater than 0') % self._chunkcachesize) elif self._chunkcachesize & (self._chunkcachesize - 1): raise error.RevlogError(_('revlog chunk cache size %r is not a ' 'power of 2') % self._chunkcachesize) self._loadindex(v, mmapindexthreshold) def _loadindex(self, v, mmapindexthreshold): indexdata = '' self._initempty = True try: with self._indexfp() as f: if (mmapindexthreshold is not None and self.opener.fstat(f).st_size >= mmapindexthreshold): indexdata = util.buffer(util.mmapread(f)) else: indexdata = f.read() if len(indexdata) > 0: v = versionformat_unpack(indexdata[:4])[0] self._initempty = False except IOError as inst: if inst.errno != errno.ENOENT: raise self.version = v self._inline = v & FLAG_INLINE_DATA self._generaldelta = v & FLAG_GENERALDELTA flags = v & ~0xFFFF fmt = v & 0xFFFF if fmt == REVLOGV0: if flags: raise error.RevlogError(_('unknown flags (%#04x) in version %d ' 'revlog %s') % (flags >> 16, fmt, self.indexfile)) elif fmt == REVLOGV1: if flags & ~REVLOGV1_FLAGS: raise error.RevlogError(_('unknown flags (%#04x) in version %d ' 'revlog %s') % (flags >> 16, fmt, self.indexfile)) elif fmt == REVLOGV2: if flags & ~REVLOGV2_FLAGS: raise error.RevlogError(_('unknown flags (%#04x) in version %d ' 'revlog %s') % (flags >> 16, fmt, self.indexfile)) else: raise error.RevlogError(_('unknown version (%d) in revlog %s') % (fmt, self.indexfile)) self._storedeltachains = True self._io = revlogio() if self.version == REVLOGV0: self._io = revlogoldio() try: d = self._io.parseindex(indexdata, self._inline) except (ValueError, IndexError): raise error.RevlogError(_("index %s is corrupted") % self.indexfile) self.index, nodemap, self._chunkcache = d if nodemap is not None: self.nodemap = self._nodecache = nodemap if not self._chunkcache: self._chunkclear() # revnum -> (chain-length, sum-delta-length) self._chaininfocache = {} # revlog header -> revlog compressor self._decompressors = {} @util.propertycache def _compressor(self): return util.compengines[self._compengine].revlogcompressor() def _indexfp(self, mode='r'): """file object for the revlog's index file""" args = {r'mode': mode} if mode != 'r': args[r'checkambig'] = self._checkambig if mode == 'w': args[r'atomictemp'] = True return self.opener(self.indexfile, **args) def _datafp(self, mode='r'): """file object for the revlog's data file""" return self.opener(self.datafile, mode=mode) @contextlib.contextmanager def _datareadfp(self, existingfp=None): """file object suitable to read data""" if existingfp is not None: yield existingfp else: if self._inline: func = self._indexfp else: func = self._datafp with func() as fp: yield fp def tip(self): return self.node(len(self.index) - 1) def __contains__(self, rev): return 0 <= rev < len(self) def __len__(self): return len(self.index) def __iter__(self): return iter(pycompat.xrange(len(self))) def revs(self, start=0, stop=None): """iterate over all rev in this revlog (from start to stop)""" return storageutil.iterrevs(len(self), start=start, stop=stop) @util.propertycache def nodemap(self): if self.index: # populate mapping down to the initial node node0 = self.index[0][7] # get around changelog filtering self.rev(node0) return self._nodecache def hasnode(self, node): try: self.rev(node) return True except KeyError: return False def candelta(self, baserev, rev): """whether two revisions (baserev, rev) can be delta-ed or not""" # Disable delta if either rev requires a content-changing flag # processor (ex. LFS). This is because such flag processor can alter # the rawtext content that the delta will be based on, and two clients # could have a same revlog node with different flags (i.e. different # rawtext contents) and the delta could be incompatible. if ((self.flags(baserev) & REVIDX_RAWTEXT_CHANGING_FLAGS) or (self.flags(rev) & REVIDX_RAWTEXT_CHANGING_FLAGS)): return False return True def clearcaches(self): self._revisioncache = None self._chainbasecache.clear() self._chunkcache = (0, '') self._pcache = {} try: self._nodecache.clearcaches() except AttributeError: self._nodecache = {nullid: nullrev} self._nodepos = None def rev(self, node): try: return self._nodecache[node] except TypeError: raise except error.RevlogError: # parsers.c radix tree lookup failed if node == wdirid or node in wdirfilenodeids: raise error.WdirUnsupported raise error.LookupError(node, self.indexfile, _('no node')) except KeyError: # pure python cache lookup failed n = self._nodecache i = self.index p = self._nodepos if p is None: p = len(i) - 1 else: assert p < len(i) for r in pycompat.xrange(p, -1, -1): v = i[r][7] n[v] = r if v == node: self._nodepos = r - 1 return r if node == wdirid or node in wdirfilenodeids: raise error.WdirUnsupported raise error.LookupError(node, self.indexfile, _('no node')) # Accessors for index entries. # First tuple entry is 8 bytes. First 6 bytes are offset. Last 2 bytes # are flags. def start(self, rev): return int(self.index[rev][0] >> 16) def flags(self, rev): return self.index[rev][0] & 0xFFFF def length(self, rev): return self.index[rev][1] def rawsize(self, rev): """return the length of the uncompressed text for a given revision""" l = self.index[rev][2] if l >= 0: return l t = self.revision(rev, raw=True) return len(t) def size(self, rev): """length of non-raw text (processed by a "read" flag processor)""" # fast path: if no "read" flag processor could change the content, # size is rawsize. note: ELLIPSIS is known to not change the content. flags = self.flags(rev) if flags & (REVIDX_KNOWN_FLAGS ^ REVIDX_ELLIPSIS) == 0: return self.rawsize(rev) return len(self.revision(rev, raw=False)) def chainbase(self, rev): base = self._chainbasecache.get(rev) if base is not None: return base index = self.index iterrev = rev base = index[iterrev][3] while base != iterrev: iterrev = base base = index[iterrev][3] self._chainbasecache[rev] = base return base def linkrev(self, rev): return self.index[rev][4] def parentrevs(self, rev): try: entry = self.index[rev] except IndexError: if rev == wdirrev: raise error.WdirUnsupported raise return entry[5], entry[6] # fast parentrevs(rev) where rev isn't filtered _uncheckedparentrevs = parentrevs def node(self, rev): try: return self.index[rev][7] except IndexError: if rev == wdirrev: raise error.WdirUnsupported raise # Derived from index values. def end(self, rev): return self.start(rev) + self.length(rev) def parents(self, node): i = self.index d = i[self.rev(node)] return i[d[5]][7], i[d[6]][7] # map revisions to nodes inline def chainlen(self, rev): return self._chaininfo(rev)[0] def _chaininfo(self, rev): chaininfocache = self._chaininfocache if rev in chaininfocache: return chaininfocache[rev] index = self.index generaldelta = self._generaldelta iterrev = rev e = index[iterrev] clen = 0 compresseddeltalen = 0 while iterrev != e[3]: clen += 1 compresseddeltalen += e[1] if generaldelta: iterrev = e[3] else: iterrev -= 1 if iterrev in chaininfocache: t = chaininfocache[iterrev] clen += t[0] compresseddeltalen += t[1] break e = index[iterrev] else: # Add text length of base since decompressing that also takes # work. For cache hits the length is already included. compresseddeltalen += e[1] r = (clen, compresseddeltalen) chaininfocache[rev] = r return r def _deltachain(self, rev, stoprev=None): """Obtain the delta chain for a revision. ``stoprev`` specifies a revision to stop at. If not specified, we stop at the base of the chain. Returns a 2-tuple of (chain, stopped) where ``chain`` is a list of revs in ascending order and ``stopped`` is a bool indicating whether ``stoprev`` was hit. """ # Try C implementation. try: return self.index.deltachain(rev, stoprev, self._generaldelta) except AttributeError: pass chain = [] # Alias to prevent attribute lookup in tight loop. index = self.index generaldelta = self._generaldelta iterrev = rev e = index[iterrev] while iterrev != e[3] and iterrev != stoprev: chain.append(iterrev) if generaldelta: iterrev = e[3] else: iterrev -= 1 e = index[iterrev] if iterrev == stoprev: stopped = True else: chain.append(iterrev) stopped = False chain.reverse() return chain, stopped def ancestors(self, revs, stoprev=0, inclusive=False): """Generate the ancestors of 'revs' in reverse topological order. Does not generate revs lower than stoprev. See the documentation for ancestor.lazyancestors for more details.""" # first, make sure start revisions aren't filtered revs = list(revs) checkrev = self.node for r in revs: checkrev(r) # and we're sure ancestors aren't filtered as well if util.safehasattr(parsers, 'rustlazyancestors'): return ancestor.rustlazyancestors( self.index, revs, stoprev=stoprev, inclusive=inclusive) return ancestor.lazyancestors(self._uncheckedparentrevs, revs, stoprev=stoprev, inclusive=inclusive) def descendants(self, revs): return dagop.descendantrevs(revs, self.revs, self.parentrevs) def findcommonmissing(self, common=None, heads=None): """Return a tuple of the ancestors of common and the ancestors of heads that are not ancestors of common. In revset terminology, we return the tuple: ::common, (::heads) - (::common) The list is sorted by revision number, meaning it is topologically sorted. 'heads' and 'common' are both lists of node IDs. If heads is not supplied, uses all of the revlog's heads. If common is not supplied, uses nullid.""" if common is None: common = [nullid] if heads is None: heads = self.heads() common = [self.rev(n) for n in common] heads = [self.rev(n) for n in heads] # we want the ancestors, but inclusive class lazyset(object): def __init__(self, lazyvalues): self.addedvalues = set() self.lazyvalues = lazyvalues def __contains__(self, value): return value in self.addedvalues or value in self.lazyvalues def __iter__(self): added = self.addedvalues for r in added: yield r for r in self.lazyvalues: if not r in added: yield r def add(self, value): self.addedvalues.add(value) def update(self, values): self.addedvalues.update(values) has = lazyset(self.ancestors(common)) has.add(nullrev) has.update(common) # take all ancestors from heads that aren't in has missing = set() visit = collections.deque(r for r in heads if r not in has) while visit: r = visit.popleft() if r in missing: continue else: missing.add(r) for p in self.parentrevs(r): if p not in has: visit.append(p) missing = list(missing) missing.sort() return has, [self.node(miss) for miss in missing] def incrementalmissingrevs(self, common=None): """Return an object that can be used to incrementally compute the revision numbers of the ancestors of arbitrary sets that are not ancestors of common. This is an ancestor.incrementalmissingancestors object. 'common' is a list of revision numbers. If common is not supplied, uses nullrev. """ if common is None: common = [nullrev] return ancestor.incrementalmissingancestors(self.parentrevs, common) def findmissingrevs(self, common=None, heads=None): """Return the revision numbers of the ancestors of heads that are not ancestors of common. More specifically, return a list of revision numbers corresponding to nodes N such that every N satisfies the following constraints: 1. N is an ancestor of some node in 'heads' 2. N is not an ancestor of any node in 'common' The list is sorted by revision number, meaning it is topologically sorted. 'heads' and 'common' are both lists of revision numbers. If heads is not supplied, uses all of the revlog's heads. If common is not supplied, uses nullid.""" if common is None: common = [nullrev] if heads is None: heads = self.headrevs() inc = self.incrementalmissingrevs(common=common) return inc.missingancestors(heads) def findmissing(self, common=None, heads=None): """Return the ancestors of heads that are not ancestors of common. More specifically, return a list of nodes N such that every N satisfies the following constraints: 1. N is an ancestor of some node in 'heads' 2. N is not an ancestor of any node in 'common' The list is sorted by revision number, meaning it is topologically sorted. 'heads' and 'common' are both lists of node IDs. If heads is not supplied, uses all of the revlog's heads. If common is not supplied, uses nullid.""" if common is None: common = [nullid] if heads is None: heads = self.heads() common = [self.rev(n) for n in common] heads = [self.rev(n) for n in heads] inc = self.incrementalmissingrevs(common=common) return [self.node(r) for r in inc.missingancestors(heads)] def nodesbetween(self, roots=None, heads=None): """Return a topological path from 'roots' to 'heads'. Return a tuple (nodes, outroots, outheads) where 'nodes' is a topologically sorted list of all nodes N that satisfy both of these constraints: 1. N is a descendant of some node in 'roots' 2. N is an ancestor of some node in 'heads' Every node is considered to be both a descendant and an ancestor of itself, so every reachable node in 'roots' and 'heads' will be included in 'nodes'. 'outroots' is the list of reachable nodes in 'roots', i.e., the subset of 'roots' that is returned in 'nodes'. Likewise, 'outheads' is the subset of 'heads' that is also in 'nodes'. 'roots' and 'heads' are both lists of node IDs. If 'roots' is unspecified, uses nullid as the only root. If 'heads' is unspecified, uses list of all of the revlog's heads.""" nonodes = ([], [], []) if roots is not None: roots = list(roots) if not roots: return nonodes lowestrev = min([self.rev(n) for n in roots]) else: roots = [nullid] # Everybody's a descendant of nullid lowestrev = nullrev if (lowestrev == nullrev) and (heads is None): # We want _all_ the nodes! return ([self.node(r) for r in self], [nullid], list(self.heads())) if heads is None: # All nodes are ancestors, so the latest ancestor is the last # node. highestrev = len(self) - 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: heads = list(heads) if not heads: return nonodes ancestors = set() # 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, False) # Start at the top and keep marking parents until we're done. nodestotag = set(heads) # 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 descendant of one of the roots # and we haven't already been marked as an ancestor ancestors.add(n) # Mark as ancestor # Add non-nullid parents to list of nodes to tag. nodestotag.update([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) if not ancestors: return nonodes # 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 > nullrev: # 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 = [root for root in roots if root in ancestors] # Recompute the lowest revision if roots: lowestrev = min([self.rev(root) for root in roots]) else: # No more roots? Return empty list return nonodes else: # We are descending from nullid, and don't need to care about # any other roots. lowestrev = nullrev roots = [nullid] # Transform our roots list into a set. descendants = set(roots) # Also, keep the original roots so we can filter out roots that aren't # 'real' roots (i.e. are descended from other roots). roots = descendants.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 descendants, empty parents will look like # they're descendants. for r in self.revs(start=max(lowestrev, 0), stop=highestrev + 1): n = self.node(r) isdescendant = False if lowestrev == nullrev: # Everybody is a descendant of nullid isdescendant = True elif n in descendants: # n is already a descendant isdescendant = True # This check only needs to be done here because all the roots # will start being marked is descendants 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 descendants, it's not a root. if (p[0] in descendants) or (p[1] in descendants): roots.remove(n) else: p = tuple(self.parents(n)) # A node is a descendant if either of its parents are # descendants. (We seeded the dependents list with the roots # up there, remember?) if (p[0] in descendants) or (p[1] in descendants): descendants.add(n) isdescendant = True if isdescendant and ((ancestors is None) or (n in ancestors)): # Only include nodes that are both descendants 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] = True 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] = True # But, obviously its parents aren't. for p in self.parents(n): heads.pop(p, None) heads = [head for head, flag in heads.iteritems() if flag] roots = list(roots) assert orderedout assert roots assert heads return (orderedout, roots, heads) def headrevs(self): try: return self.index.headrevs() except AttributeError: return self._headrevs() def computephases(self, roots): return self.index.computephasesmapsets(roots) def _headrevs(self): count = len(self) if not count: return [nullrev] # we won't iter over filtered rev so nobody is a head at start ishead = [0] * (count + 1) index = self.index for r in self: ishead[r] = 1 # I may be an head e = index[r] ishead[e[5]] = ishead[e[6]] = 0 # my parent are not return [r for r, val in enumerate(ishead) if val] def heads(self, start=None, stop=None): """return the list of all nodes that have no children if start is specified, only heads that are descendants of start will be returned if stop is specified, it will consider all the revs from stop as if they had no children """ if start is None and stop is None: if not len(self): return [nullid] return [self.node(r) for r in self.headrevs()] if start is None: start = nullrev else: start = self.rev(start) stoprevs = set(self.rev(n) for n in stop or []) revs = dagop.headrevssubset(self.revs, self.parentrevs, startrev=start, stoprevs=stoprevs) return [self.node(rev) for rev in revs] def children(self, node): """find the children of a given node""" c = [] p = self.rev(node) for r in self.revs(start=p + 1): prevs = [pr for pr in self.parentrevs(r) if pr != nullrev] if prevs: for pr in prevs: if pr == p: c.append(self.node(r)) elif p == nullrev: c.append(self.node(r)) return c def commonancestorsheads(self, a, b): """calculate all the heads of the common ancestors of nodes a and b""" a, b = self.rev(a), self.rev(b) ancs = self._commonancestorsheads(a, b) return pycompat.maplist(self.node, ancs) def _commonancestorsheads(self, *revs): """calculate all the heads of the common ancestors of revs""" try: ancs = self.index.commonancestorsheads(*revs) except (AttributeError, OverflowError): # C implementation failed ancs = ancestor.commonancestorsheads(self.parentrevs, *revs) return ancs def isancestor(self, a, b): """return True if node a is an ancestor of node b A revision is considered an ancestor of itself.""" a, b = self.rev(a), self.rev(b) return self.isancestorrev(a, b) def isancestorrev(self, a, b): """return True if revision a is an ancestor of revision b A revision is considered an ancestor of itself. The implementation of this is trivial but the use of commonancestorsheads is not.""" if a == nullrev: return True elif a == b: return True elif a > b: return False return a in self._commonancestorsheads(a, b) def ancestor(self, a, b): """calculate the "best" common ancestor of nodes a and b""" a, b = self.rev(a), self.rev(b) try: ancs = self.index.ancestors(a, b) except (AttributeError, OverflowError): ancs = ancestor.ancestors(self.parentrevs, a, b) if ancs: # choose a consistent winner when there's a tie return min(map(self.node, ancs)) return nullid def _match(self, id): if isinstance(id, int): # rev return self.node(id) if len(id) == 20: # possibly a binary node # odds of a binary node being all hex in ASCII are 1 in 10**25 try: node = id self.rev(node) # quick search the index return node except error.LookupError: pass # may be partial hex id try: # str(rev) rev = int(id) if "%d" % rev != id: raise ValueError if rev < 0: rev = len(self) + rev if rev < 0 or rev >= len(self): raise ValueError return self.node(rev) except (ValueError, OverflowError): pass if len(id) == 40: try: # a full hex nodeid? node = bin(id) self.rev(node) return node except (TypeError, error.LookupError): pass def _partialmatch(self, id): # we don't care wdirfilenodeids as they should be always full hash maybewdir = wdirhex.startswith(id) try: partial = self.index.partialmatch(id) if partial and self.hasnode(partial): if maybewdir: # single 'ff...' match in radix tree, ambiguous with wdir raise error.RevlogError return partial if maybewdir: # no 'ff...' match in radix tree, wdir identified raise error.WdirUnsupported return None except error.RevlogError: # parsers.c radix tree lookup gave multiple matches # fast path: for unfiltered changelog, radix tree is accurate if not getattr(self, 'filteredrevs', None): raise error.AmbiguousPrefixLookupError( id, self.indexfile, _('ambiguous identifier')) # fall through to slow path that filters hidden revisions except (AttributeError, ValueError): # we are pure python, or key was too short to search radix tree pass if id in self._pcache: return self._pcache[id] if len(id) <= 40: try: # hex(node)[:...] l = len(id) // 2 # grab an even number of digits prefix = bin(id[:l * 2]) nl = [e[7] for e in self.index if e[7].startswith(prefix)] nl = [n for n in nl if hex(n).startswith(id) and self.hasnode(n)] if nullhex.startswith(id): nl.append(nullid) if len(nl) > 0: if len(nl) == 1 and not maybewdir: self._pcache[id] = nl[0] return nl[0] raise error.AmbiguousPrefixLookupError( id, self.indexfile, _('ambiguous identifier')) if maybewdir: raise error.WdirUnsupported return None except TypeError: pass def lookup(self, id): """locate a node based on: - revision number or str(revision number) - nodeid or subset of hex nodeid """ n = self._match(id) if n is not None: return n n = self._partialmatch(id) if n: return n raise error.LookupError(id, self.indexfile, _('no match found')) def shortest(self, node, minlength=1): """Find the shortest unambiguous prefix that matches node.""" def isvalid(prefix): try: node = self._partialmatch(prefix) except error.AmbiguousPrefixLookupError: return False except error.WdirUnsupported: # single 'ff...' match return True if node is None: raise error.LookupError(node, self.indexfile, _('no node')) return True def maybewdir(prefix): return all(c == 'f' for c in prefix) hexnode = hex(node) def disambiguate(hexnode, minlength): """Disambiguate against wdirid.""" for length in range(minlength, 41): prefix = hexnode[:length] if not maybewdir(prefix): return prefix if not getattr(self, 'filteredrevs', None): try: length = max(self.index.shortest(node), minlength) return disambiguate(hexnode, length) except error.RevlogError: if node != wdirid: raise error.LookupError(node, self.indexfile, _('no node')) except AttributeError: # Fall through to pure code pass if node == wdirid: for length in range(minlength, 41): prefix = hexnode[:length] if isvalid(prefix): return prefix for length in range(minlength, 41): prefix = hexnode[:length] if isvalid(prefix): return disambiguate(hexnode, length) def cmp(self, node, text): """compare text with a given file revision returns True if text is different than what is stored. """ p1, p2 = self.parents(node) return storageutil.hashrevisionsha1(text, p1, p2) != node def _cachesegment(self, offset, data): """Add a segment to the revlog cache. Accepts an absolute offset and the data that is at that location. """ o, d = self._chunkcache # try to add to existing cache if o + len(d) == offset and len(d) + len(data) < _chunksize: self._chunkcache = o, d + data else: self._chunkcache = offset, data def _readsegment(self, offset, length, df=None): """Load a segment of raw data from the revlog. Accepts an absolute offset, length to read, and an optional existing file handle to read from. If an existing file handle is passed, it will be seeked and the original seek position will NOT be restored. Returns a str or buffer of raw byte data. """ # Cache data both forward and backward around the requested # data, in a fixed size window. This helps speed up operations # involving reading the revlog backwards. cachesize = self._chunkcachesize realoffset = offset & ~(cachesize - 1) reallength = (((offset + length + cachesize) & ~(cachesize - 1)) - realoffset) with self._datareadfp(df) as df: df.seek(realoffset) d = df.read(reallength) self._cachesegment(realoffset, d) if offset != realoffset or reallength != length: return util.buffer(d, offset - realoffset, length) return d def _getsegment(self, offset, length, df=None): """Obtain a segment of raw data from the revlog. Accepts an absolute offset, length of bytes to obtain, and an optional file handle to the already-opened revlog. If the file handle is used, it's original seek position will not be preserved. Requests for data may be returned from a cache. Returns a str or a buffer instance of raw byte data. """ o, d = self._chunkcache l = len(d) # is it in the cache? cachestart = offset - o cacheend = cachestart + length if cachestart >= 0 and cacheend <= l: if cachestart == 0 and cacheend == l: return d # avoid a copy return util.buffer(d, cachestart, cacheend - cachestart) return self._readsegment(offset, length, df=df) def _getsegmentforrevs(self, startrev, endrev, df=None): """Obtain a segment of raw data corresponding to a range of revisions. Accepts the start and end revisions and an optional already-open file handle to be used for reading. If the file handle is read, its seek position will not be preserved. Requests for data may be satisfied by a cache. Returns a 2-tuple of (offset, data) for the requested range of revisions. Offset is the integer offset from the beginning of the revlog and data is a str or buffer of the raw byte data. Callers will need to call ``self.start(rev)`` and ``self.length(rev)`` to determine where each revision's data begins and ends. """ # Inlined self.start(startrev) & self.end(endrev) for perf reasons # (functions are expensive). index = self.index istart = index[startrev] start = int(istart[0] >> 16) if startrev == endrev: end = start + istart[1] else: iend = index[endrev] end = int(iend[0] >> 16) + iend[1] if self._inline: start += (startrev + 1) * self._io.size end += (endrev + 1) * self._io.size length = end - start return start, self._getsegment(start, length, df=df) def _chunk(self, rev, df=None): """Obtain a single decompressed chunk for a revision. Accepts an integer revision and an optional already-open file handle to be used for reading. If used, the seek position of the file will not be preserved. Returns a str holding uncompressed data for the requested revision. """ return self.decompress(self._getsegmentforrevs(rev, rev, df=df)[1]) def _chunks(self, revs, df=None, targetsize=None): """Obtain decompressed chunks for the specified revisions. Accepts an iterable of numeric revisions that are assumed to be in ascending order. Also accepts an optional already-open file handle to be used for reading. If used, the seek position of the file will not be preserved. This function is similar to calling ``self._chunk()`` multiple times, but is faster. Returns a list with decompressed data for each requested revision. """ if not revs: return [] start = self.start length = self.length inline = self._inline iosize = self._io.size buffer = util.buffer l = [] ladd = l.append if not self._withsparseread: slicedchunks = (revs,) else: slicedchunks = deltautil.slicechunk(self, revs, targetsize=targetsize) for revschunk in slicedchunks: firstrev = revschunk[0] # Skip trailing revisions with empty diff for lastrev in revschunk[::-1]: if length(lastrev) != 0: break try: offset, data = self._getsegmentforrevs(firstrev, lastrev, df=df) except OverflowError: # issue4215 - we can't cache a run of chunks greater than # 2G on Windows return [self._chunk(rev, df=df) for rev in revschunk] decomp = self.decompress for rev in revschunk: chunkstart = start(rev) if inline: chunkstart += (rev + 1) * iosize chunklength = length(rev) ladd(decomp(buffer(data, chunkstart - offset, chunklength))) return l def _chunkclear(self): """Clear the raw chunk cache.""" self._chunkcache = (0, '') def deltaparent(self, rev): """return deltaparent of the given revision""" base = self.index[rev][3] if base == rev: return nullrev elif self._generaldelta: return base else: return rev - 1 def issnapshot(self, rev): """tells whether rev is a snapshot """ if rev == nullrev: return True deltap = self.deltaparent(rev) if deltap == nullrev: return True p1, p2 = self.parentrevs(rev) if deltap in (p1, p2): return False return self.issnapshot(deltap) def snapshotdepth(self, rev): """number of snapshot in the chain before this one""" if not self.issnapshot(rev): raise error.ProgrammingError('revision %d not a snapshot') return len(self._deltachain(rev)[0]) - 1 def revdiff(self, rev1, rev2): """return or calculate a delta between two revisions The delta calculated is in binary form and is intended to be written to revlog data directly. So this function needs raw revision data. """ if rev1 != nullrev and self.deltaparent(rev2) == rev1: return bytes(self._chunk(rev2)) return mdiff.textdiff(self.revision(rev1, raw=True), self.revision(rev2, raw=True)) def revision(self, nodeorrev, _df=None, raw=False): """return an uncompressed revision of a given node or revision number. _df - an existing file handle to read from. (internal-only) raw - an optional argument specifying if the revision data is to be treated as raw data when applying flag transforms. 'raw' should be set to True when generating changegroups or in debug commands. """ if isinstance(nodeorrev, int): rev = nodeorrev node = self.node(rev) else: node = nodeorrev rev = None cachedrev = None flags = None rawtext = None if node == nullid: return "" if self._revisioncache: if self._revisioncache[0] == node: # _cache only stores rawtext if raw: return self._revisioncache[2] # duplicated, but good for perf if rev is None: rev = self.rev(node) if flags is None: flags = self.flags(rev) # no extra flags set, no flag processor runs, text = rawtext if flags == REVIDX_DEFAULT_FLAGS: return self._revisioncache[2] # rawtext is reusable. need to run flag processor rawtext = self._revisioncache[2] cachedrev = self._revisioncache[1] # look up what we need to read if rawtext is None: if rev is None: rev = self.rev(node) chain, stopped = self._deltachain(rev, stoprev=cachedrev) if stopped: rawtext = self._revisioncache[2] # drop cache to save memory self._revisioncache = None targetsize = None rawsize = self.index[rev][2] if 0 <= rawsize: targetsize = 4 * rawsize bins = self._chunks(chain, df=_df, targetsize=targetsize) if rawtext is None: rawtext = bytes(bins[0]) bins = bins[1:] rawtext = mdiff.patches(rawtext, bins) self._revisioncache = (node, rev, rawtext) if flags is None: if rev is None: rev = self.rev(node) flags = self.flags(rev) text, validatehash = self._processflags(rawtext, flags, 'read', raw=raw) if validatehash: self.checkhash(text, node, rev=rev) return text def hash(self, text, p1, p2): """Compute a node hash. Available as a function so that subclasses can replace the hash as needed. """ return storageutil.hashrevisionsha1(text, p1, p2) def _processflags(self, text, flags, operation, raw=False): """Inspect revision data flags and applies transforms defined by registered flag processors. ``text`` - the revision data to process ``flags`` - the revision flags ``operation`` - the operation being performed (read or write) ``raw`` - an optional argument describing if the raw transform should be applied. This method processes the flags in the order (or reverse order if ``operation`` is 'write') defined by REVIDX_FLAGS_ORDER, applying the flag processors registered for present flags. The order of flags defined in REVIDX_FLAGS_ORDER needs to be stable to allow non-commutativity. Returns a 2-tuple of ``(text, validatehash)`` where ``text`` is the processed text and ``validatehash`` is a bool indicating whether the returned text should be checked for hash integrity. Note: If the ``raw`` argument is set, it has precedence over the operation and will only update the value of ``validatehash``. """ # fast path: no flag processors will run if flags == 0: return text, True if not operation in ('read', 'write'): raise error.ProgrammingError(_("invalid '%s' operation") % operation) # Check all flags are known. if flags & ~REVIDX_KNOWN_FLAGS: raise error.RevlogError(_("incompatible revision flag '%#x'") % (flags & ~REVIDX_KNOWN_FLAGS)) validatehash = True # Depending on the operation (read or write), the order might be # reversed due to non-commutative transforms. orderedflags = REVIDX_FLAGS_ORDER if operation == 'write': orderedflags = reversed(orderedflags) for flag in orderedflags: # If a flagprocessor has been registered for a known flag, apply the # related operation transform and update result tuple. if flag & flags: vhash = True if flag not in self._flagprocessors: message = _("missing processor for flag '%#x'") % (flag) raise error.RevlogError(message) processor = self._flagprocessors[flag] if processor is not None: readtransform, writetransform, rawtransform = processor if raw: vhash = rawtransform(self, text) elif operation == 'read': text, vhash = readtransform(self, text) else: # write operation text, vhash = writetransform(self, text) validatehash = validatehash and vhash return text, validatehash def checkhash(self, text, node, p1=None, p2=None, rev=None): """Check node hash integrity. Available as a function so that subclasses can extend hash mismatch behaviors as needed. """ try: if p1 is None and p2 is None: p1, p2 = self.parents(node) if node != self.hash(text, p1, p2): # Clear the revision cache on hash failure. The revision cache # only stores the raw revision and clearing the cache does have # the side-effect that we won't have a cache hit when the raw # revision data is accessed. But this case should be rare and # it is extra work to teach the cache about the hash # verification state. if self._revisioncache and self._revisioncache[0] == node: self._revisioncache = None revornode = rev if revornode is None: revornode = templatefilters.short(hex(node)) raise error.RevlogError(_("integrity check failed on %s:%s") % (self.indexfile, pycompat.bytestr(revornode))) except error.RevlogError: if self._censorable and storageutil.iscensoredtext(text): raise error.CensoredNodeError(self.indexfile, node, text) raise def _enforceinlinesize(self, tr, fp=None): """Check if the revlog is too big for inline and convert if so. This should be called after revisions are added to the revlog. If the revlog has grown too large to be an inline revlog, it will convert it to use multiple index and data files. """ tiprev = len(self) - 1 if (not self._inline or (self.start(tiprev) + self.length(tiprev)) < _maxinline): return trinfo = tr.find(self.indexfile) if trinfo is None: raise error.RevlogError(_("%s not found in the transaction") % self.indexfile) trindex = trinfo[2] if trindex is not None: dataoff = self.start(trindex) else: # revlog was stripped at start of transaction, use all leftover data trindex = len(self) - 1 dataoff = self.end(tiprev) tr.add(self.datafile, dataoff) if fp: fp.flush() fp.close() with self._datafp('w') as df: for r in self: df.write(self._getsegmentforrevs(r, r)[1]) with self._indexfp('w') as fp: self.version &= ~FLAG_INLINE_DATA self._inline = False io = self._io for i in self: e = io.packentry(self.index[i], self.node, self.version, i) fp.write(e) # the temp file replace the real index when we exit the context # manager tr.replace(self.indexfile, trindex * self._io.size) self._chunkclear() def _nodeduplicatecallback(self, transaction, node): """called when trying to add a node already stored. """ def addrevision(self, text, transaction, link, p1, p2, cachedelta=None, node=None, flags=REVIDX_DEFAULT_FLAGS, deltacomputer=None): """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 cachedelta - an optional precomputed delta node - nodeid of revision; typically node is not specified, and it is computed by default as hash(text, p1, p2), however subclasses might use different hashing method (and override checkhash() in such case) flags - the known flags to set on the revision deltacomputer - an optional deltacomputer instance shared between multiple calls """ if link == nullrev: raise error.RevlogError(_("attempted to add linkrev -1 to %s") % self.indexfile) if flags: node = node or self.hash(text, p1, p2) rawtext, validatehash = self._processflags(text, flags, 'write') # If the flag processor modifies the revision data, ignore any provided # cachedelta. if rawtext != text: cachedelta = None if len(rawtext) > _maxentrysize: raise error.RevlogError( _("%s: size of %d bytes exceeds maximum revlog storage of 2GiB") % (self.indexfile, len(rawtext))) node = node or self.hash(rawtext, p1, p2) if node in self.nodemap: return node if validatehash: self.checkhash(rawtext, node, p1=p1, p2=p2) return self.addrawrevision(rawtext, transaction, link, p1, p2, node, flags, cachedelta=cachedelta, deltacomputer=deltacomputer) def addrawrevision(self, rawtext, transaction, link, p1, p2, node, flags, cachedelta=None, deltacomputer=None): """add a raw revision with known flags, node and parents useful when reusing a revision not stored in this revlog (ex: received over wire, or read from an external bundle). """ dfh = None if not self._inline: dfh = self._datafp("a+") ifh = self._indexfp("a+") try: return self._addrevision(node, rawtext, transaction, link, p1, p2, flags, cachedelta, ifh, dfh, deltacomputer=deltacomputer) finally: if dfh: dfh.close() ifh.close() def compress(self, data): """Generate a possibly-compressed representation of data.""" if not data: return '', data compressed = self._compressor.compress(data) if compressed: # The revlog compressor added the header in the returned data. return '', compressed if data[0:1] == '\0': return '', data return 'u', data def decompress(self, data): """Decompress a revlog chunk. The chunk is expected to begin with a header identifying the format type so it can be routed to an appropriate decompressor. """ if not data: return data # Revlogs are read much more frequently than they are written and many # chunks only take microseconds to decompress, so performance is # important here. # # We can make a few assumptions about revlogs: # # 1) the majority of chunks will be compressed (as opposed to inline # raw data). # 2) decompressing *any* data will likely by at least 10x slower than # returning raw inline data. # 3) we want to prioritize common and officially supported compression # engines # # It follows that we want to optimize for "decompress compressed data # when encoded with common and officially supported compression engines" # case over "raw data" and "data encoded by less common or non-official # compression engines." That is why we have the inline lookup first # followed by the compengines lookup. # # According to `hg perfrevlogchunks`, this is ~0.5% faster for zlib # compressed chunks. And this matters for changelog and manifest reads. t = data[0:1] if t == 'x': try: return _zlibdecompress(data) except zlib.error as e: raise error.RevlogError(_('revlog decompress error: %s') % stringutil.forcebytestr(e)) # '\0' is more common than 'u' so it goes first. elif t == '\0': return data elif t == 'u': return util.buffer(data, 1) try: compressor = self._decompressors[t] except KeyError: try: engine = util.compengines.forrevlogheader(t) compressor = engine.revlogcompressor() self._decompressors[t] = compressor except KeyError: raise error.RevlogError(_('unknown compression type %r') % t) return compressor.decompress(data) def _addrevision(self, node, rawtext, transaction, link, p1, p2, flags, cachedelta, ifh, dfh, alwayscache=False, deltacomputer=None): """internal function to add revisions to the log see addrevision for argument descriptions. note: "addrevision" takes non-raw text, "_addrevision" takes raw text. if "deltacomputer" is not provided or None, a defaultdeltacomputer will be used. invariants: - rawtext is optional (can be None); if not set, cachedelta must be set. if both are set, they must correspond to each other. """ if node == nullid: raise error.RevlogError(_("%s: attempt to add null revision") % self.indexfile) if node == wdirid or node in wdirfilenodeids: raise error.RevlogError(_("%s: attempt to add wdir revision") % self.indexfile) if self._inline: fh = ifh else: fh = dfh btext = [rawtext] curr = len(self) prev = curr - 1 offset = self.end(prev) p1r, p2r = self.rev(p1), self.rev(p2) # full versions are inserted when the needed deltas # become comparable to the uncompressed text if rawtext is None: # need rawtext size, before changed by flag processors, which is # the non-raw size. use revlog explicitly to avoid filelog's extra # logic that might remove metadata size. textlen = mdiff.patchedsize(revlog.size(self, cachedelta[0]), cachedelta[1]) else: textlen = len(rawtext) if deltacomputer is None: deltacomputer = deltautil.deltacomputer(self) revinfo = _revisioninfo(node, p1, p2, btext, textlen, cachedelta, flags) deltainfo = deltacomputer.finddeltainfo(revinfo, fh) e = (offset_type(offset, flags), deltainfo.deltalen, textlen, deltainfo.base, link, p1r, p2r, node) self.index.append(e) self.nodemap[node] = curr # Reset the pure node cache start lookup offset to account for new # revision. if self._nodepos is not None: self._nodepos = curr entry = self._io.packentry(e, self.node, self.version, curr) self._writeentry(transaction, ifh, dfh, entry, deltainfo.data, link, offset) rawtext = btext[0] if alwayscache and rawtext is None: rawtext = deltacomputer.buildtext(revinfo, fh) if type(rawtext) == bytes: # only accept immutable objects self._revisioncache = (node, curr, rawtext) self._chainbasecache[curr] = deltainfo.chainbase return node def _writeentry(self, transaction, ifh, dfh, entry, data, link, offset): # Files opened in a+ mode have inconsistent behavior on various # platforms. Windows requires that a file positioning call be made # when the file handle transitions between reads and writes. See # 3686fa2b8eee and the mixedfilemodewrapper in windows.py. On other # platforms, Python or the platform itself can be buggy. Some versions # of Solaris have been observed to not append at the end of the file # if the file was seeked to before the end. See issue4943 for more. # # We work around this issue by inserting a seek() before writing. # Note: This is likely not necessary on Python 3. ifh.seek(0, os.SEEK_END) if dfh: dfh.seek(0, os.SEEK_END) curr = len(self) - 1 if not self._inline: transaction.add(self.datafile, offset) transaction.add(self.indexfile, curr * len(entry)) if data[0]: dfh.write(data[0]) dfh.write(data[1]) ifh.write(entry) else: offset += curr * self._io.size transaction.add(self.indexfile, offset, curr) ifh.write(entry) ifh.write(data[0]) ifh.write(data[1]) self._enforceinlinesize(transaction, ifh) def addgroup(self, deltas, linkmapper, transaction, addrevisioncb=None): """ add a delta group 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. If ``addrevisioncb`` is defined, it will be called with arguments of this revlog and the node that was added. """ nodes = [] r = len(self) end = 0 if r: end = self.end(r - 1) ifh = self._indexfp("a+") isize = r * self._io.size if self._inline: transaction.add(self.indexfile, end + isize, r) dfh = None else: transaction.add(self.indexfile, isize, r) transaction.add(self.datafile, end) dfh = self._datafp("a+") def flush(): if dfh: dfh.flush() ifh.flush() try: deltacomputer = deltautil.deltacomputer(self) # loop through our set of deltas for data in deltas: node, p1, p2, linknode, deltabase, delta, flags = data link = linkmapper(linknode) flags = flags or REVIDX_DEFAULT_FLAGS nodes.append(node) if node in self.nodemap: self._nodeduplicatecallback(transaction, node) # this can happen if two branches make the same change continue for p in (p1, p2): if p not in self.nodemap: raise error.LookupError(p, self.indexfile, _('unknown parent')) if deltabase not in self.nodemap: raise error.LookupError(deltabase, self.indexfile, _('unknown delta base')) baserev = self.rev(deltabase) if baserev != nullrev and self.iscensored(baserev): # if base is censored, delta must be full replacement in a # single patch operation hlen = struct.calcsize(">lll") oldlen = self.rawsize(baserev) newlen = len(delta) - hlen if delta[:hlen] != mdiff.replacediffheader(oldlen, newlen): raise error.CensoredBaseError(self.indexfile, self.node(baserev)) if not flags and self._peek_iscensored(baserev, delta, flush): flags |= REVIDX_ISCENSORED # We assume consumers of addrevisioncb will want to retrieve # the added revision, which will require a call to # revision(). revision() will fast path if there is a cache # hit. So, we tell _addrevision() to always cache in this case. # We're only using addgroup() in the context of changegroup # generation so the revision data can always be handled as raw # by the flagprocessor. self._addrevision(node, None, transaction, link, p1, p2, flags, (baserev, delta), ifh, dfh, alwayscache=bool(addrevisioncb), deltacomputer=deltacomputer) if addrevisioncb: addrevisioncb(self, node) if not dfh and not self._inline: # addrevision switched from inline to conventional # reopen the index ifh.close() dfh = self._datafp("a+") ifh = self._indexfp("a+") finally: if dfh: dfh.close() ifh.close() return nodes def iscensored(self, rev): """Check if a file revision is censored.""" if not self._censorable: return False return self.flags(rev) & REVIDX_ISCENSORED def _peek_iscensored(self, baserev, delta, flush): """Quickly check if a delta produces a censored revision.""" if not self._censorable: return False return storageutil.deltaiscensored(delta, baserev, self.rawsize) def getstrippoint(self, minlink): """find the minimum rev that must be stripped to strip the linkrev Returns a tuple containing the minimum rev and a set of all revs that have linkrevs that will be broken by this strip. """ return storageutil.resolvestripinfo(minlink, len(self) - 1, self.headrevs(), self.linkrev, self.parentrevs) def strip(self, minlink, transaction): """truncate the revlog on the first revision with a linkrev >= minlink This function is called when we're stripping revision minlink and its descendants from the repository. We have to remove all revisions with linkrev >= minlink, because the equivalent changelog revisions will be renumbered after the strip. So we truncate the revlog on the first of these revisions, and trust that the caller has saved the revisions that shouldn't be removed and that it'll re-add them after this truncation. """ if len(self) == 0: return rev, _ = self.getstrippoint(minlink) if rev == len(self): return # first truncate the files on disk end = self.start(rev) if not self._inline: transaction.add(self.datafile, end) end = rev * self._io.size else: end += rev * self._io.size transaction.add(self.indexfile, end) # then reset internal state in memory to forget those revisions self._revisioncache = None self._chaininfocache = {} self._chunkclear() for x in pycompat.xrange(rev, len(self)): del self.nodemap[self.node(x)] del self.index[rev:-1] self._nodepos = None def checksize(self): expected = 0 if len(self): expected = max(0, self.end(len(self) - 1)) try: with self._datafp() as f: f.seek(0, 2) actual = f.tell() dd = actual - expected except IOError as inst: if inst.errno != errno.ENOENT: raise dd = 0 try: f = self.opener(self.indexfile) f.seek(0, 2) actual = f.tell() f.close() s = self._io.size i = max(0, actual // s) di = actual - (i * s) if self._inline: databytes = 0 for r in self: databytes += max(0, self.length(r)) dd = 0 di = actual - len(self) * s - databytes except IOError as inst: if inst.errno != errno.ENOENT: raise di = 0 return (dd, di) def files(self): res = [self.indexfile] if not self._inline: res.append(self.datafile) return res def emitrevisions(self, nodes, nodesorder=None, revisiondata=False, assumehaveparentrevisions=False, deltamode=repository.CG_DELTAMODE_STD): if nodesorder not in ('nodes', 'storage', 'linear', None): raise error.ProgrammingError('unhandled value for nodesorder: %s' % nodesorder) if nodesorder is None and not self._generaldelta: nodesorder = 'storage' if (not self._storedeltachains and deltamode != repository.CG_DELTAMODE_PREV): deltamode = repository.CG_DELTAMODE_FULL return storageutil.emitrevisions( self, nodes, nodesorder, revlogrevisiondelta, deltaparentfn=self.deltaparent, candeltafn=self.candelta, rawsizefn=self.rawsize, revdifffn=self.revdiff, flagsfn=self.flags, deltamode=deltamode, revisiondata=revisiondata, assumehaveparentrevisions=assumehaveparentrevisions) DELTAREUSEALWAYS = 'always' DELTAREUSESAMEREVS = 'samerevs' DELTAREUSENEVER = 'never' DELTAREUSEFULLADD = 'fulladd' DELTAREUSEALL = {'always', 'samerevs', 'never', 'fulladd'} def clone(self, tr, destrevlog, addrevisioncb=None, deltareuse=DELTAREUSESAMEREVS, deltabothparents=None): """Copy this revlog to another, possibly with format changes. The destination revlog will contain the same revisions and nodes. However, it may not be bit-for-bit identical due to e.g. delta encoding differences. The ``deltareuse`` argument control how deltas from the existing revlog are preserved in the destination revlog. The argument can have the following values: DELTAREUSEALWAYS Deltas will always be reused (if possible), even if the destination revlog would not select the same revisions for the delta. This is the fastest mode of operation. DELTAREUSESAMEREVS Deltas will be reused if the destination revlog would pick the same revisions for the delta. This mode strikes a balance between speed and optimization. DELTAREUSENEVER Deltas will never be reused. This is the slowest mode of execution. This mode can be used to recompute deltas (e.g. if the diff/delta algorithm changes). Delta computation can be slow, so the choice of delta reuse policy can significantly affect run time. The default policy (``DELTAREUSESAMEREVS``) strikes a balance between two extremes. Deltas will be reused if they are appropriate. But if the delta could choose a better revision, it will do so. This means if you are converting a non-generaldelta revlog to a generaldelta revlog, deltas will be recomputed if the delta's parent isn't a parent of the revision. In addition to the delta policy, the ``deltabothparents`` argument controls whether to compute deltas against both parents for merges. By default, the current default is used. """ if deltareuse not in self.DELTAREUSEALL: raise ValueError(_('value for deltareuse invalid: %s') % deltareuse) if len(destrevlog): raise ValueError(_('destination revlog is not empty')) if getattr(self, 'filteredrevs', None): raise ValueError(_('source revlog has filtered revisions')) if getattr(destrevlog, 'filteredrevs', None): raise ValueError(_('destination revlog has filtered revisions')) # lazydeltabase controls whether to reuse a cached delta, if possible. oldlazydeltabase = destrevlog._lazydeltabase oldamd = destrevlog._deltabothparents try: if deltareuse == self.DELTAREUSEALWAYS: destrevlog._lazydeltabase = True elif deltareuse == self.DELTAREUSESAMEREVS: destrevlog._lazydeltabase = False destrevlog._deltabothparents = deltabothparents or oldamd populatecachedelta = deltareuse in (self.DELTAREUSEALWAYS, self.DELTAREUSESAMEREVS) deltacomputer = deltautil.deltacomputer(destrevlog) index = self.index for rev in self: entry = index[rev] # Some classes override linkrev to take filtered revs into # account. Use raw entry from index. flags = entry[0] & 0xffff linkrev = entry[4] p1 = index[entry[5]][7] p2 = index[entry[6]][7] node = entry[7] # (Possibly) reuse the delta from the revlog if allowed and # the revlog chunk is a delta. cachedelta = None rawtext = None if populatecachedelta: dp = self.deltaparent(rev) if dp != nullrev: cachedelta = (dp, bytes(self._chunk(rev))) if not cachedelta: rawtext = self.revision(rev, raw=True) if deltareuse == self.DELTAREUSEFULLADD: destrevlog.addrevision(rawtext, tr, linkrev, p1, p2, cachedelta=cachedelta, node=node, flags=flags, deltacomputer=deltacomputer) else: ifh = destrevlog.opener(destrevlog.indexfile, 'a+', checkambig=False) dfh = None if not destrevlog._inline: dfh = destrevlog.opener(destrevlog.datafile, 'a+') try: destrevlog._addrevision(node, rawtext, tr, linkrev, p1, p2, flags, cachedelta, ifh, dfh, deltacomputer=deltacomputer) finally: if dfh: dfh.close() ifh.close() if addrevisioncb: addrevisioncb(self, rev, node) finally: destrevlog._lazydeltabase = oldlazydeltabase destrevlog._deltabothparents = oldamd def censorrevision(self, tr, censornode, tombstone=b''): if (self.version & 0xFFFF) == REVLOGV0: raise error.RevlogError(_('cannot censor with version %d revlogs') % self.version) censorrev = self.rev(censornode) tombstone = storageutil.packmeta({b'censored': tombstone}, b'') if len(tombstone) > self.rawsize(censorrev): raise error.Abort(_('censor tombstone must be no longer than ' 'censored data')) # Rewriting the revlog in place is hard. Our strategy for censoring is # to create a new revlog, copy all revisions to it, then replace the # revlogs on transaction close. newindexfile = self.indexfile + b'.tmpcensored' newdatafile = self.datafile + b'.tmpcensored' # This is a bit dangerous. We could easily have a mismatch of state. newrl = revlog(self.opener, newindexfile, newdatafile, censorable=True) newrl.version = self.version newrl._generaldelta = self._generaldelta newrl._io = self._io for rev in self.revs(): node = self.node(rev) p1, p2 = self.parents(node) if rev == censorrev: newrl.addrawrevision(tombstone, tr, self.linkrev(censorrev), p1, p2, censornode, REVIDX_ISCENSORED) if newrl.deltaparent(rev) != nullrev: raise error.Abort(_('censored revision stored as delta; ' 'cannot censor'), hint=_('censoring of revlogs is not ' 'fully implemented; please report ' 'this bug')) continue if self.iscensored(rev): if self.deltaparent(rev) != nullrev: raise error.Abort(_('cannot censor due to censored ' 'revision having delta stored')) rawtext = self._chunk(rev) else: rawtext = self.revision(rev, raw=True) newrl.addrawrevision(rawtext, tr, self.linkrev(rev), p1, p2, node, self.flags(rev)) tr.addbackup(self.indexfile, location='store') if not self._inline: tr.addbackup(self.datafile, location='store') self.opener.rename(newrl.indexfile, self.indexfile) if not self._inline: self.opener.rename(newrl.datafile, self.datafile) self.clearcaches() self._loadindex(self.version, None) def verifyintegrity(self, state): """Verifies the integrity of the revlog. Yields ``revlogproblem`` instances describing problems that are found. """ dd, di = self.checksize() if dd: yield revlogproblem(error=_('data length off by %d bytes') % dd) if di: yield revlogproblem(error=_('index contains %d extra bytes') % di) version = self.version & 0xFFFF # The verifier tells us what version revlog we should be. if version != state['expectedversion']: yield revlogproblem( warning=_("warning: '%s' uses revlog format %d; expected %d") % (self.indexfile, version, state['expectedversion'])) state['skipread'] = set() for rev in self: node = self.node(rev) # Verify contents. 4 cases to care about: # # common: the most common case # rename: with a rename # meta: file content starts with b'\1\n', the metadata # header defined in filelog.py, but without a rename # ext: content stored externally # # More formally, their differences are shown below: # # | common | rename | meta | ext # ------------------------------------------------------- # flags() | 0 | 0 | 0 | not 0 # renamed() | False | True | False | ? # rawtext[0:2]=='\1\n'| False | True | True | ? # # "rawtext" means the raw text stored in revlog data, which # could be retrieved by "revision(rev, raw=True)". "text" # mentioned below is "revision(rev, raw=False)". # # There are 3 different lengths stored physically: # 1. L1: rawsize, stored in revlog index # 2. L2: len(rawtext), stored in revlog data # 3. L3: len(text), stored in revlog data if flags==0, or # possibly somewhere else if flags!=0 # # L1 should be equal to L2. L3 could be different from them. # "text" may or may not affect commit hash depending on flag # processors (see revlog.addflagprocessor). # # | common | rename | meta | ext # ------------------------------------------------- # rawsize() | L1 | L1 | L1 | L1 # size() | L1 | L2-LM | L1(*) | L1 (?) # len(rawtext) | L2 | L2 | L2 | L2 # len(text) | L2 | L2 | L2 | L3 # len(read()) | L2 | L2-LM | L2-LM | L3 (?) # # LM: length of metadata, depending on rawtext # (*): not ideal, see comment in filelog.size # (?): could be "- len(meta)" if the resolved content has # rename metadata # # Checks needed to be done: # 1. length check: L1 == L2, in all cases. # 2. hash check: depending on flag processor, we may need to # use either "text" (external), or "rawtext" (in revlog). try: skipflags = state.get('skipflags', 0) if skipflags: skipflags &= self.flags(rev) if skipflags: state['skipread'].add(node) else: # Side-effect: read content and verify hash. self.revision(node) l1 = self.rawsize(rev) l2 = len(self.revision(node, raw=True)) if l1 != l2: yield revlogproblem( error=_('unpacked size is %d, %d expected') % (l2, l1), node=node) except error.CensoredNodeError: if state['erroroncensored']: yield revlogproblem(error=_('censored file data'), node=node) state['skipread'].add(node) except Exception as e: yield revlogproblem( error=_('unpacking %s: %s') % (short(node), stringutil.forcebytestr(e)), node=node) state['skipread'].add(node) def storageinfo(self, exclusivefiles=False, sharedfiles=False, revisionscount=False, trackedsize=False, storedsize=False): d = {} if exclusivefiles: d['exclusivefiles'] = [(self.opener, self.indexfile)] if not self._inline: d['exclusivefiles'].append((self.opener, self.datafile)) if sharedfiles: d['sharedfiles'] = [] if revisionscount: d['revisionscount'] = len(self) if trackedsize: d['trackedsize'] = sum(map(self.rawsize, iter(self))) if storedsize: d['storedsize'] = sum(self.opener.stat(path).st_size for path in self.files()) return d