from __future__ import absolute_import import collections import errno import shutil import struct from .i18n import _ from .node import ( bin, hex, nullhex, nullid, ) from .pycompat import delattr from . import ( error, filemerge, pycompat, util, ) from .utils import hashutil _pack = struct.pack _unpack = struct.unpack def _droponode(data): # used for compatibility for v1 bits = data.split(b'\0') bits = bits[:-2] + bits[-1:] return b'\0'.join(bits) def _filectxorabsent(hexnode, ctx, f): if hexnode == nullhex: return filemerge.absentfilectx(ctx, f) else: return ctx[f] # Merge state record types. See ``mergestate`` docs for more. #### # merge records which records metadata about a current merge # exists only once in a mergestate ##### RECORD_LOCAL = b'L' RECORD_OTHER = b'O' # record merge labels RECORD_LABELS = b'l' # store info about merge driver used and it's state RECORD_MERGE_DRIVER_STATE = b'm' ##### # record extra information about files, with one entry containing info about one # file. Hence, multiple of them can exists ##### RECORD_FILE_VALUES = b'f' ##### # merge records which represents state of individual merges of files/folders # These are top level records for each entry containing merge related info. # Each record of these has info about one file. Hence multiple of them can # exists ##### RECORD_MERGED = b'F' RECORD_CHANGEDELETE_CONFLICT = b'C' RECORD_MERGE_DRIVER_MERGE = b'D' # the path was dir on one side of merge and file on another RECORD_PATH_CONFLICT = b'P' ##### # possible state which a merge entry can have. These are stored inside top-level # merge records mentioned just above. ##### MERGE_RECORD_UNRESOLVED = b'u' MERGE_RECORD_RESOLVED = b'r' MERGE_RECORD_UNRESOLVED_PATH = b'pu' MERGE_RECORD_RESOLVED_PATH = b'pr' MERGE_RECORD_DRIVER_RESOLVED = b'd' # represents that the file was automatically merged in favor # of other version. This info is used on commit. MERGE_RECORD_MERGED_OTHER = b'o' ##### # top level record which stores other unknown records. Multiple of these can # exists ##### RECORD_OVERRIDE = b't' ##### # possible states which a merge driver can have. These are stored inside a # RECORD_MERGE_DRIVER_STATE entry ##### MERGE_DRIVER_STATE_UNMARKED = b'u' MERGE_DRIVER_STATE_MARKED = b'm' MERGE_DRIVER_STATE_SUCCESS = b's' ##### # legacy records which are no longer used but kept to prevent breaking BC ##### # This record was release in 5.4 and usage was removed in 5.5 LEGACY_RECORD_RESOLVED_OTHER = b'R' ACTION_FORGET = b'f' ACTION_REMOVE = b'r' ACTION_ADD = b'a' ACTION_GET = b'g' ACTION_PATH_CONFLICT = b'p' ACTION_PATH_CONFLICT_RESOLVE = b'pr' ACTION_ADD_MODIFIED = b'am' ACTION_CREATED = b'c' ACTION_DELETED_CHANGED = b'dc' ACTION_CHANGED_DELETED = b'cd' ACTION_MERGE = b'm' ACTION_LOCAL_DIR_RENAME_GET = b'dg' ACTION_DIR_RENAME_MOVE_LOCAL = b'dm' ACTION_KEEP = b'k' ACTION_EXEC = b'e' ACTION_CREATED_MERGE = b'cm' class mergestate(object): '''track 3-way merge state of individual files The merge state is stored on disk when needed. Two files are used: one with an old format (version 1), and one with a new format (version 2). Version 2 stores a superset of the data in version 1, including new kinds of records in the future. For more about the new format, see the documentation for `_readrecordsv2`. Each record can contain arbitrary content, and has an associated type. This `type` should be a letter. If `type` is uppercase, the record is mandatory: versions of Mercurial that don't support it should abort. If `type` is lowercase, the record can be safely ignored. Currently known records: L: the node of the "local" part of the merge (hexified version) O: the node of the "other" part of the merge (hexified version) F: a file to be merged entry C: a change/delete or delete/change conflict D: a file that the external merge driver will merge internally (experimental) P: a path conflict (file vs directory) m: the external merge driver defined for this merge plus its run state (experimental) f: a (filename, dictionary) tuple of optional values for a given file l: the labels for the parts of the merge. Merge driver run states (experimental): u: driver-resolved files unmarked -- needs to be run next time we're about to resolve or commit m: driver-resolved files marked -- only needs to be run before commit s: success/skipped -- does not need to be run any more Merge record states (stored in self._state, indexed by filename): u: unresolved conflict r: resolved conflict pu: unresolved path conflict (file conflicts with directory) pr: resolved path conflict d: driver-resolved conflict The resolve command transitions between 'u' and 'r' for conflicts and 'pu' and 'pr' for path conflicts. ''' statepathv1 = b'merge/state' statepathv2 = b'merge/state2' @staticmethod def clean(repo, node=None, other=None, labels=None): """Initialize a brand new merge state, removing any existing state on disk.""" ms = mergestate(repo) ms.reset(node, other, labels) return ms @staticmethod def read(repo): """Initialize the merge state, reading it from disk.""" ms = mergestate(repo) ms._read() return ms def __init__(self, repo): """Initialize the merge state. Do not use this directly! Instead call read() or clean().""" self._repo = repo self._dirty = False self._labels = None def reset(self, node=None, other=None, labels=None): self._state = {} self._stateextras = collections.defaultdict(dict) self._local = None self._other = None self._labels = labels for var in ('localctx', 'otherctx'): if var in vars(self): delattr(self, var) if node: self._local = node self._other = other self._readmergedriver = None if self.mergedriver: self._mdstate = MERGE_DRIVER_STATE_SUCCESS else: self._mdstate = MERGE_DRIVER_STATE_UNMARKED shutil.rmtree(self._repo.vfs.join(b'merge'), True) self._results = {} self._dirty = False def _read(self): """Analyse each record content to restore a serialized state from disk This function process "record" entry produced by the de-serialization of on disk file. """ self._state = {} self._stateextras = collections.defaultdict(dict) self._local = None self._other = None for var in ('localctx', 'otherctx'): if var in vars(self): delattr(self, var) self._readmergedriver = None self._mdstate = MERGE_DRIVER_STATE_SUCCESS unsupported = set() records = self._readrecords() for rtype, record in records: if rtype == RECORD_LOCAL: self._local = bin(record) elif rtype == RECORD_OTHER: self._other = bin(record) elif rtype == RECORD_MERGE_DRIVER_STATE: bits = record.split(b'\0', 1) mdstate = bits[1] if len(mdstate) != 1 or mdstate not in ( MERGE_DRIVER_STATE_UNMARKED, MERGE_DRIVER_STATE_MARKED, MERGE_DRIVER_STATE_SUCCESS, ): # the merge driver should be idempotent, so just rerun it mdstate = MERGE_DRIVER_STATE_UNMARKED self._readmergedriver = bits[0] self._mdstate = mdstate elif rtype in ( RECORD_MERGED, RECORD_CHANGEDELETE_CONFLICT, RECORD_PATH_CONFLICT, RECORD_MERGE_DRIVER_MERGE, LEGACY_RECORD_RESOLVED_OTHER, ): bits = record.split(b'\0') self._state[bits[0]] = bits[1:] elif rtype == RECORD_FILE_VALUES: filename, rawextras = record.split(b'\0', 1) extraparts = rawextras.split(b'\0') extras = {} i = 0 while i < len(extraparts): extras[extraparts[i]] = extraparts[i + 1] i += 2 self._stateextras[filename] = extras elif rtype == RECORD_LABELS: labels = record.split(b'\0', 2) self._labels = [l for l in labels if len(l) > 0] elif not rtype.islower(): unsupported.add(rtype) # contains a mapping of form: # {filename : (merge_return_value, action_to_be_performed} # these are results of re-running merge process # this dict is used to perform actions on dirstate caused by re-running # the merge self._results = {} self._dirty = False if unsupported: raise error.UnsupportedMergeRecords(unsupported) def _readrecords(self): """Read merge state from disk and return a list of record (TYPE, data) We read data from both v1 and v2 files and decide which one to use. V1 has been used by version prior to 2.9.1 and contains less data than v2. We read both versions and check if no data in v2 contradicts v1. If there is not contradiction we can safely assume that both v1 and v2 were written at the same time and use the extract data in v2. If there is contradiction we ignore v2 content as we assume an old version of Mercurial has overwritten the mergestate file and left an old v2 file around. returns list of record [(TYPE, data), ...]""" v1records = self._readrecordsv1() v2records = self._readrecordsv2() if self._v1v2match(v1records, v2records): return v2records else: # v1 file is newer than v2 file, use it # we have to infer the "other" changeset of the merge # we cannot do better than that with v1 of the format mctx = self._repo[None].parents()[-1] v1records.append((RECORD_OTHER, mctx.hex())) # add place holder "other" file node information # nobody is using it yet so we do no need to fetch the data # if mctx was wrong `mctx[bits[-2]]` may fails. for idx, r in enumerate(v1records): if r[0] == RECORD_MERGED: bits = r[1].split(b'\0') bits.insert(-2, b'') v1records[idx] = (r[0], b'\0'.join(bits)) return v1records def _v1v2match(self, v1records, v2records): oldv2 = set() # old format version of v2 record for rec in v2records: if rec[0] == RECORD_LOCAL: oldv2.add(rec) elif rec[0] == RECORD_MERGED: # drop the onode data (not contained in v1) oldv2.add((RECORD_MERGED, _droponode(rec[1]))) for rec in v1records: if rec not in oldv2: return False else: return True def _readrecordsv1(self): """read on disk merge state for version 1 file returns list of record [(TYPE, data), ...] Note: the "F" data from this file are one entry short (no "other file node" entry) """ records = [] try: f = self._repo.vfs(self.statepathv1) for i, l in enumerate(f): if i == 0: records.append((RECORD_LOCAL, l[:-1])) else: records.append((RECORD_MERGED, l[:-1])) f.close() except IOError as err: if err.errno != errno.ENOENT: raise return records def _readrecordsv2(self): """read on disk merge state for version 2 file This format is a list of arbitrary records of the form: [type][length][content] `type` is a single character, `length` is a 4 byte integer, and `content` is an arbitrary byte sequence of length `length`. Mercurial versions prior to 3.7 have a bug where if there are unsupported mandatory merge records, attempting to clear out the merge state with hg update --clean or similar aborts. The 't' record type works around that by writing out what those versions treat as an advisory record, but later versions interpret as special: the first character is the 'real' record type and everything onwards is the data. Returns list of records [(TYPE, data), ...].""" records = [] try: f = self._repo.vfs(self.statepathv2) data = f.read() off = 0 end = len(data) while off < end: rtype = data[off : off + 1] off += 1 length = _unpack(b'>I', data[off : (off + 4)])[0] off += 4 record = data[off : (off + length)] off += length if rtype == RECORD_OVERRIDE: rtype, record = record[0:1], record[1:] records.append((rtype, record)) f.close() except IOError as err: if err.errno != errno.ENOENT: raise return records @util.propertycache def mergedriver(self): # protect against the following: # - A configures a malicious merge driver in their hgrc, then # pauses the merge # - A edits their hgrc to remove references to the merge driver # - A gives a copy of their entire repo, including .hg, to B # - B inspects .hgrc and finds it to be clean # - B then continues the merge and the malicious merge driver # gets invoked configmergedriver = self._repo.ui.config( b'experimental', b'mergedriver' ) if ( self._readmergedriver is not None and self._readmergedriver != configmergedriver ): raise error.ConfigError( _(b"merge driver changed since merge started"), hint=_(b"revert merge driver change or abort merge"), ) return configmergedriver @util.propertycache def local(self): if self._local is None: msg = b"local accessed but self._local isn't set" raise error.ProgrammingError(msg) return self._local @util.propertycache def localctx(self): return self._repo[self.local] @util.propertycache def other(self): if self._other is None: msg = b"other accessed but self._other isn't set" raise error.ProgrammingError(msg) return self._other @util.propertycache def otherctx(self): return self._repo[self.other] def active(self): """Whether mergestate is active. Returns True if there appears to be mergestate. This is a rough proxy for "is a merge in progress." """ return bool(self._local) or bool(self._state) def commit(self): """Write current state on disk (if necessary)""" if self._dirty: records = self._makerecords() self._writerecords(records) self._dirty = False def _makerecords(self): records = [] records.append((RECORD_LOCAL, hex(self._local))) records.append((RECORD_OTHER, hex(self._other))) if self.mergedriver: records.append( ( RECORD_MERGE_DRIVER_STATE, b'\0'.join([self.mergedriver, self._mdstate]), ) ) # Write out state items. In all cases, the value of the state map entry # is written as the contents of the record. The record type depends on # the type of state that is stored, and capital-letter records are used # to prevent older versions of Mercurial that do not support the feature # from loading them. for filename, v in pycompat.iteritems(self._state): if v[0] == MERGE_RECORD_DRIVER_RESOLVED: # Driver-resolved merge. These are stored in 'D' records. records.append( (RECORD_MERGE_DRIVER_MERGE, b'\0'.join([filename] + v)) ) elif v[0] in ( MERGE_RECORD_UNRESOLVED_PATH, MERGE_RECORD_RESOLVED_PATH, ): # Path conflicts. These are stored in 'P' records. The current # resolution state ('pu' or 'pr') is stored within the record. records.append( (RECORD_PATH_CONFLICT, b'\0'.join([filename] + v)) ) elif v[0] == MERGE_RECORD_MERGED_OTHER: records.append((RECORD_MERGED, b'\0'.join([filename] + v))) elif v[1] == nullhex or v[6] == nullhex: # Change/Delete or Delete/Change conflicts. These are stored in # 'C' records. v[1] is the local file, and is nullhex when the # file is deleted locally ('dc'). v[6] is the remote file, and # is nullhex when the file is deleted remotely ('cd'). records.append( (RECORD_CHANGEDELETE_CONFLICT, b'\0'.join([filename] + v)) ) else: # Normal files. These are stored in 'F' records. records.append((RECORD_MERGED, b'\0'.join([filename] + v))) for filename, extras in sorted(pycompat.iteritems(self._stateextras)): rawextras = b'\0'.join( b'%s\0%s' % (k, v) for k, v in pycompat.iteritems(extras) ) records.append( (RECORD_FILE_VALUES, b'%s\0%s' % (filename, rawextras)) ) if self._labels is not None: labels = b'\0'.join(self._labels) records.append((RECORD_LABELS, labels)) return records def _writerecords(self, records): """Write current state on disk (both v1 and v2)""" self._writerecordsv1(records) self._writerecordsv2(records) def _writerecordsv1(self, records): """Write current state on disk in a version 1 file""" f = self._repo.vfs(self.statepathv1, b'wb') irecords = iter(records) lrecords = next(irecords) assert lrecords[0] == RECORD_LOCAL f.write(hex(self._local) + b'\n') for rtype, data in irecords: if rtype == RECORD_MERGED: f.write(b'%s\n' % _droponode(data)) f.close() def _writerecordsv2(self, records): """Write current state on disk in a version 2 file See the docstring for _readrecordsv2 for why we use 't'.""" # these are the records that all version 2 clients can read allowlist = (RECORD_LOCAL, RECORD_OTHER, RECORD_MERGED) f = self._repo.vfs(self.statepathv2, b'wb') for key, data in records: assert len(key) == 1 if key not in allowlist: key, data = RECORD_OVERRIDE, b'%s%s' % (key, data) format = b'>sI%is' % len(data) f.write(_pack(format, key, len(data), data)) f.close() @staticmethod def getlocalkey(path): """hash the path of a local file context for storage in the .hg/merge directory.""" return hex(hashutil.sha1(path).digest()) def add(self, fcl, fco, fca, fd): """add a new (potentially?) conflicting file the merge state fcl: file context for local, fco: file context for remote, fca: file context for ancestors, fd: file path of the resulting merge. note: also write the local version to the `.hg/merge` directory. """ if fcl.isabsent(): localkey = nullhex else: localkey = mergestate.getlocalkey(fcl.path()) self._repo.vfs.write(b'merge/' + localkey, fcl.data()) self._state[fd] = [ MERGE_RECORD_UNRESOLVED, localkey, fcl.path(), fca.path(), hex(fca.filenode()), fco.path(), hex(fco.filenode()), fcl.flags(), ] self._stateextras[fd] = {b'ancestorlinknode': hex(fca.node())} self._dirty = True def addpathconflict(self, path, frename, forigin): """add a new conflicting path to the merge state path: the path that conflicts frename: the filename the conflicting file was renamed to forigin: origin of the file ('l' or 'r' for local/remote) """ self._state[path] = [MERGE_RECORD_UNRESOLVED_PATH, frename, forigin] self._dirty = True def addmergedother(self, path): self._state[path] = [MERGE_RECORD_MERGED_OTHER, nullhex, nullhex] self._dirty = True def __contains__(self, dfile): return dfile in self._state def __getitem__(self, dfile): return self._state[dfile][0] def __iter__(self): return iter(sorted(self._state)) def files(self): return self._state.keys() def mark(self, dfile, state): self._state[dfile][0] = state self._dirty = True def mdstate(self): return self._mdstate def unresolved(self): """Obtain the paths of unresolved files.""" for f, entry in pycompat.iteritems(self._state): if entry[0] in ( MERGE_RECORD_UNRESOLVED, MERGE_RECORD_UNRESOLVED_PATH, ): yield f def driverresolved(self): """Obtain the paths of driver-resolved files.""" for f, entry in self._state.items(): if entry[0] == MERGE_RECORD_DRIVER_RESOLVED: yield f def extras(self, filename): return self._stateextras[filename] def _resolve(self, preresolve, dfile, wctx): """rerun merge process for file path `dfile`. Returns whether the merge was completed and the return value of merge obtained from filemerge._filemerge(). """ if self[dfile] in (MERGE_RECORD_RESOLVED, MERGE_RECORD_DRIVER_RESOLVED): return True, 0 if self._state[dfile][0] == MERGE_RECORD_MERGED_OTHER: return True, 0 stateentry = self._state[dfile] state, localkey, lfile, afile, anode, ofile, onode, flags = stateentry octx = self._repo[self._other] extras = self.extras(dfile) anccommitnode = extras.get(b'ancestorlinknode') if anccommitnode: actx = self._repo[anccommitnode] else: actx = None fcd = _filectxorabsent(localkey, wctx, dfile) fco = _filectxorabsent(onode, octx, ofile) # TODO: move this to filectxorabsent fca = self._repo.filectx(afile, fileid=anode, changectx=actx) # "premerge" x flags flo = fco.flags() fla = fca.flags() if b'x' in flags + flo + fla and b'l' not in flags + flo + fla: if fca.node() == nullid and flags != flo: if preresolve: self._repo.ui.warn( _( b'warning: cannot merge flags for %s ' b'without common ancestor - keeping local flags\n' ) % afile ) elif flags == fla: flags = flo if preresolve: # restore local if localkey != nullhex: f = self._repo.vfs(b'merge/' + localkey) wctx[dfile].write(f.read(), flags) f.close() else: wctx[dfile].remove(ignoremissing=True) complete, merge_ret, deleted = filemerge.premerge( self._repo, wctx, self._local, lfile, fcd, fco, fca, labels=self._labels, ) else: complete, merge_ret, deleted = filemerge.filemerge( self._repo, wctx, self._local, lfile, fcd, fco, fca, labels=self._labels, ) if merge_ret is None: # If return value of merge is None, then there are no real conflict del self._state[dfile] self._stateextras.pop(dfile, None) self._dirty = True elif not merge_ret: self.mark(dfile, MERGE_RECORD_RESOLVED) if complete: action = None if deleted: if fcd.isabsent(): # dc: local picked. Need to drop if present, which may # happen on re-resolves. action = ACTION_FORGET else: # cd: remote picked (or otherwise deleted) action = ACTION_REMOVE else: if fcd.isabsent(): # dc: remote picked action = ACTION_GET elif fco.isabsent(): # cd: local picked if dfile in self.localctx: action = ACTION_ADD_MODIFIED else: action = ACTION_ADD # else: regular merges (no action necessary) self._results[dfile] = merge_ret, action return complete, merge_ret def preresolve(self, dfile, wctx): """run premerge process for dfile Returns whether the merge is complete, and the exit code.""" return self._resolve(True, dfile, wctx) def resolve(self, dfile, wctx): """run merge process (assuming premerge was run) for dfile Returns the exit code of the merge.""" return self._resolve(False, dfile, wctx)[1] def counts(self): """return counts for updated, merged and removed files in this session""" updated, merged, removed = 0, 0, 0 for r, action in pycompat.itervalues(self._results): if r is None: updated += 1 elif r == 0: if action == ACTION_REMOVE: removed += 1 else: merged += 1 return updated, merged, removed def unresolvedcount(self): """get unresolved count for this merge (persistent)""" return len(list(self.unresolved())) def actions(self): """return lists of actions to perform on the dirstate""" actions = { ACTION_REMOVE: [], ACTION_FORGET: [], ACTION_ADD: [], ACTION_ADD_MODIFIED: [], ACTION_GET: [], } for f, (r, action) in pycompat.iteritems(self._results): if action is not None: actions[action].append((f, None, b"merge result")) return actions def queueremove(self, f): """queues a file to be removed from the dirstate Meant for use by custom merge drivers.""" self._results[f] = 0, ACTION_REMOVE def queueadd(self, f): """queues a file to be added to the dirstate Meant for use by custom merge drivers.""" self._results[f] = 0, ACTION_ADD def queueget(self, f): """queues a file to be marked modified in the dirstate Meant for use by custom merge drivers.""" self._results[f] = 0, ACTION_GET def recordupdates(repo, actions, branchmerge, getfiledata): """record merge actions to the dirstate""" # remove (must come first) for f, args, msg in actions.get(ACTION_REMOVE, []): if branchmerge: repo.dirstate.remove(f) else: repo.dirstate.drop(f) # forget (must come first) for f, args, msg in actions.get(ACTION_FORGET, []): repo.dirstate.drop(f) # resolve path conflicts for f, args, msg in actions.get(ACTION_PATH_CONFLICT_RESOLVE, []): (f0, origf0) = args repo.dirstate.add(f) repo.dirstate.copy(origf0, f) if f0 == origf0: repo.dirstate.remove(f0) else: repo.dirstate.drop(f0) # re-add for f, args, msg in actions.get(ACTION_ADD, []): repo.dirstate.add(f) # re-add/mark as modified for f, args, msg in actions.get(ACTION_ADD_MODIFIED, []): if branchmerge: repo.dirstate.normallookup(f) else: repo.dirstate.add(f) # exec change for f, args, msg in actions.get(ACTION_EXEC, []): repo.dirstate.normallookup(f) # keep for f, args, msg in actions.get(ACTION_KEEP, []): pass # get for f, args, msg in actions.get(ACTION_GET, []): if branchmerge: repo.dirstate.otherparent(f) else: parentfiledata = getfiledata[f] if getfiledata else None repo.dirstate.normal(f, parentfiledata=parentfiledata) # merge for f, args, msg in actions.get(ACTION_MERGE, []): f1, f2, fa, move, anc = args if branchmerge: # We've done a branch merge, mark this file as merged # so that we properly record the merger later repo.dirstate.merge(f) if f1 != f2: # copy/rename if move: repo.dirstate.remove(f1) if f1 != f: repo.dirstate.copy(f1, f) else: repo.dirstate.copy(f2, f) else: # We've update-merged a locally modified file, so # we set the dirstate to emulate a normal checkout # of that file some time in the past. Thus our # merge will appear as a normal local file # modification. if f2 == f: # file not locally copied/moved repo.dirstate.normallookup(f) if move: repo.dirstate.drop(f1) # directory rename, move local for f, args, msg in actions.get(ACTION_DIR_RENAME_MOVE_LOCAL, []): f0, flag = args if branchmerge: repo.dirstate.add(f) repo.dirstate.remove(f0) repo.dirstate.copy(f0, f) else: repo.dirstate.normal(f) repo.dirstate.drop(f0) # directory rename, get for f, args, msg in actions.get(ACTION_LOCAL_DIR_RENAME_GET, []): f0, flag = args if branchmerge: repo.dirstate.add(f) repo.dirstate.copy(f0, f) else: repo.dirstate.normal(f)