dirstate: make parents() faster.

This allows localrepository.status() to avoid reading all but the
first 40 bytes of the dirstate in the common case of running "hg
status".

mercurial/dirstate.py

@@ -1,555 +1,577 b''
 """
 dirstate.py - working directory tracking for mercurial
 
 Copyright 2005, 2006 Matt Mackall <[e-mail]>
 
 This software may be used and distributed according to the terms
 of the GNU General Public License, incorporated herein by reference.
 """
 
 from node import *
 from i18n import _
 import struct, os, time, bisect, stat, strutil, util, re, errno
 
 class dirstate(object):
     format = ">cllll"
 
     def __init__(self, opener, ui, root):
         self.opener = opener
         self.root = root
         self.dirty = 0
         self.ui = ui
         self.map = None
+        self.fp = None
         self.pl = None
         self.dirs = None
         self.copymap = {}
         self.ignorefunc = None
         self._branch = None
 
     def wjoin(self, f):
         return os.path.join(self.root, f)
 
     def getcwd(self):
         cwd = os.getcwd()
         if cwd == self.root: return ''
         # self.root ends with a path separator if self.root is '/' or 'C:\'
         rootsep = self.root
         if not rootsep.endswith(os.sep):
             rootsep += os.sep
         if cwd.startswith(rootsep):
             return cwd[len(rootsep):]
         else:
             # we're outside the repo. return an absolute path.
             return cwd
 
     def hgignore(self):
         '''return the contents of .hgignore files as a list of patterns.
 
         the files parsed for patterns include:
         .hgignore in the repository root
         any additional files specified in the [ui] section of ~/.hgrc
 
         trailing white space is dropped.
         the escape character is backslash.
         comments start with #.
         empty lines are skipped.
 
         lines can be of the following formats:
 
         syntax: regexp # defaults following lines to non-rooted regexps
         syntax: glob   # defaults following lines to non-rooted globs
         re:pattern     # non-rooted regular expression
         glob:pattern   # non-rooted glob
         pattern        # pattern of the current default type'''
         syntaxes = {'re': 'relre:', 'regexp': 'relre:', 'glob': 'relglob:'}
         def parselines(fp):
             for line in fp:
                 escape = False
                 for i in xrange(len(line)):
                     if escape: escape = False
                     elif line[i] == '\\': escape = True
                     elif line[i] == '#': break
                 line = line[:i].rstrip()
                 if line: yield line
         repoignore = self.wjoin('.hgignore')
         files = [repoignore]
         files.extend(self.ui.hgignorefiles())
         pats = {}
         for f in files:
             try:
                 pats[f] = []
                 fp = open(f)
                 syntax = 'relre:'
                 for line in parselines(fp):
                     if line.startswith('syntax:'):
                         s = line[7:].strip()
                         try:
                             syntax = syntaxes[s]
                         except KeyError:
                             self.ui.warn(_("%s: ignoring invalid "
                                            "syntax '%s'\n") % (f, s))
                         continue
                     pat = syntax + line
                     for s in syntaxes.values():
                         if line.startswith(s):
                             pat = line
                             break
                     pats[f].append(pat)
             except IOError, inst:
                 if f != repoignore:
                     self.ui.warn(_("skipping unreadable ignore file"
                                    " '%s': %s\n") % (f, inst.strerror))
         return pats
 
     def ignore(self, fn):
         '''default match function used by dirstate and
         localrepository.  this honours the repository .hgignore file
         and any other files specified in the [ui] section of .hgrc.'''
         if not self.ignorefunc:
             ignore = self.hgignore()
             allpats = []
             [allpats.extend(patlist) for patlist in ignore.values()]
             if allpats:
                 try:
                     files, self.ignorefunc, anypats = (
                         util.matcher(self.root, inc=allpats, src='.hgignore'))
                 except util.Abort:
                     # Re-raise an exception where the src is the right file
                     for f, patlist in ignore.items():
                         files, self.ignorefunc, anypats = (
                             util.matcher(self.root, inc=patlist, src=f))
             else:
                 self.ignorefunc = util.never
         return self.ignorefunc(fn)
 
     def __del__(self):
         if self.dirty:
             self.write()
 
     def __getitem__(self, key):
         try:
             return self.map[key]
         except TypeError:
             self.lazyread()
             return self[key]
 
+    _unknown = ('?', 0, 0, 0)
+
+    def get(self, key):
+        try:
+            return self[key]
+        except KeyError:
+            return self._unknown
+
     def __contains__(self, key):
         self.lazyread()
         return key in self.map
 
     def parents(self):
-        self.lazyread()
+        if self.pl is None:
+            self.pl = [nullid, nullid]
+            try:
+                self.fp = self.opener('dirstate')
+                st = self.fp.read(40)
+                if len(st) == 40:
+                    self.pl = st[:20], st[20:40]
+            except IOError, err:
+                if err.errno != errno.ENOENT: raise
         return self.pl
 
     def branch(self):
         if not self._branch:
             try:
                 self._branch = self.opener("branch").read().strip()\
                                or "default"
             except IOError:
                 self._branch = "default"
         return self._branch
 
     def markdirty(self):
         if not self.dirty:
             self.dirty = 1
 
     def setparents(self, p1, p2=nullid):
         self.lazyread()
         self.markdirty()
         self.pl = p1, p2
 
     def setbranch(self, branch):
         self._branch = branch
         self.opener("branch", "w").write(branch + '\n')
 
     def state(self, key):
         try:
             return self[key][0]
         except KeyError:
             return "?"
 
     def lazyread(self):
         if self.map is None:
             self.read()
 
     def parse(self, st):
         self.pl = [st[:20], st[20: 40]]
 
         # deref fields so they will be local in loop
         map = self.map
         copymap = self.copymap
         format = self.format
         unpack = struct.unpack
 
         pos = 40
         e_size = struct.calcsize(format)
 
         while pos < len(st):
             newpos = pos + e_size
             e = unpack(format, st[pos:newpos])
             l = e[4]
             pos = newpos
             newpos = pos + l
             f = st[pos:newpos]
             if '\0' in f:
                 f, c = f.split('\0')
                 copymap[f] = c
             map[f] = e[:4]
             pos = newpos
 
     def read(self):
         self.map = {}
         self.pl = [nullid, nullid]
         try:
-            st = self.opener("dirstate").read()
+            if self.fp:
+                self.fp.seek(0)
+                st = self.fp.read()
+                self.fp = None
+            else:
+                st = self.opener("dirstate").read()
             if st:
                 self.parse(st)
         except IOError, err:
             if err.errno != errno.ENOENT: raise
 
     def copy(self, source, dest):
         self.lazyread()
         self.markdirty()
         self.copymap[dest] = source
 
     def copied(self, file):
         return self.copymap.get(file, None)
 
     def copies(self):
         return self.copymap
 
     def initdirs(self):
         if self.dirs is None:
             self.dirs = {}
             for f in self.map:
                 self.updatedirs(f, 1)
 
     def updatedirs(self, path, delta):
         if self.dirs is not None:
             for c in strutil.findall(path, '/'):
                 pc = path[:c]
                 self.dirs.setdefault(pc, 0)
                 self.dirs[pc] += delta
 
     def checkinterfering(self, files):
         def prefixes(f):
             for c in strutil.rfindall(f, '/'):
                 yield f[:c]
         self.lazyread()
         self.initdirs()
         seendirs = {}
         for f in files:
             # shadows
             if self.dirs.get(f):
                 raise util.Abort(_('directory named %r already in dirstate') %
                                  f)
             for d in prefixes(f):
                 if d in seendirs:
                     break
                 if d in self.map:
                     raise util.Abort(_('file named %r already in dirstate') %
                                      d)
                 seendirs[d] = True
             # disallowed
             if '\r' in f or '\n' in f:
                 raise util.Abort(_("'\\n' and '\\r' disallowed in filenames"))
 
     def update(self, files, state, **kw):
         ''' current states:
         n  normal
         m  needs merging
         r  marked for removal
         a  marked for addition'''
 
         if not files: return
         self.lazyread()
         self.markdirty()
         if state == "a":
             self.initdirs()
             self.checkinterfering(files)
         for f in files:
             if state == "r":
                 self.map[f] = ('r', 0, 0, 0)
                 self.updatedirs(f, -1)
             else:
                 if state == "a":
                     self.updatedirs(f, 1)
                 s = os.lstat(self.wjoin(f))
                 st_size = kw.get('st_size', s.st_size)
                 st_mtime = kw.get('st_mtime', s.st_mtime)
                 self.map[f] = (state, s.st_mode, st_size, st_mtime)
             if self.copymap.has_key(f):
                 del self.copymap[f]
 
     def forget(self, files):
         if not files: return
         self.lazyread()
         self.markdirty()
         self.initdirs()
         for f in files:
             try:
                 del self.map[f]
                 self.updatedirs(f, -1)
             except KeyError:
                 self.ui.warn(_("not in dirstate: %s!\n") % f)
                 pass
 
     def clear(self):
         self.map = {}
         self.copymap = {}
         self.dirs = None
         self.markdirty()
 
     def rebuild(self, parent, files):
         self.clear()
         for f in files:
             if files.execf(f):
                 self.map[f] = ('n', 0777, -1, 0)
             else:
                 self.map[f] = ('n', 0666, -1, 0)
         self.pl = (parent, nullid)
         self.markdirty()
 
     def write(self):
         if not self.dirty:
             return
         st = self.opener("dirstate", "w", atomictemp=True)
         st.write("".join(self.pl))
         for f, e in self.map.items():
             c = self.copied(f)
             if c:
                 f = f + "\0" + c
             e = struct.pack(self.format, e[0], e[1], e[2], e[3], len(f))
             st.write(e + f)
         st.rename()
         self.dirty = 0
 
     def filterfiles(self, files):
         ret = {}
         unknown = []
 
         for x in files:
             if x == '.':
                 return self.map.copy()
             if x not in self.map:
                 unknown.append(x)
             else:
                 ret[x] = self.map[x]
 
         if not unknown:
             return ret
 
         b = self.map.keys()
         b.sort()
         blen = len(b)
 
         for x in unknown:
             bs = bisect.bisect(b, "%s%s" % (x, '/'))
             while bs < blen:
                 s = b[bs]
                 if len(s) > len(x) and s.startswith(x):
                     ret[s] = self.map[s]
                 else:
                     break
                 bs += 1
         return ret
 
     def supported_type(self, f, st, verbose=False):
         if stat.S_ISREG(st.st_mode) or stat.S_ISLNK(st.st_mode):
             return True
         if verbose:
             kind = 'unknown'
             if stat.S_ISCHR(st.st_mode): kind = _('character device')
             elif stat.S_ISBLK(st.st_mode): kind = _('block device')
             elif stat.S_ISFIFO(st.st_mode): kind = _('fifo')
             elif stat.S_ISSOCK(st.st_mode): kind = _('socket')
             elif stat.S_ISDIR(st.st_mode): kind = _('directory')
             self.ui.warn(_('%s: unsupported file type (type is %s)\n') % (
                 util.pathto(self.root, self.getcwd(), f),
                 kind))
         return False
 
     def walk(self, files=None, match=util.always, badmatch=None):
         # filter out the stat
         for src, f, st in self.statwalk(files, match, badmatch=badmatch):
             yield src, f
 
     def statwalk(self, files=None, match=util.always, ignored=False,
                  badmatch=None, directories=False):
         '''
         walk recursively through the directory tree, finding all files
         matched by the match function
 
         results are yielded in a tuple (src, filename, st), where src
         is one of:
         'f' the file was found in the directory tree
         'd' the file is a directory of the tree
         'm' the file was only in the dirstate and not in the tree
         'b' file was not found and matched badmatch
 
         and st is the stat result if the file was found in the directory.
         '''
         self.lazyread()
 
         # walk all files by default
         if not files:
             files = ['.']
             dc = self.map.copy()
         else:
             files = util.unique(files)
             dc = self.filterfiles(files)
 
         def imatch(file_):
             if file_ not in dc and self.ignore(file_):
                 return False
             return match(file_)
 
         ignore = self.ignore
         if ignored:
             imatch = match
             ignore = util.never
 
         # self.root may end with a path separator when self.root == '/'
         common_prefix_len = len(self.root)
         if not self.root.endswith(os.sep):
             common_prefix_len += 1
         # recursion free walker, faster than os.walk.
         def findfiles(s):
             work = [s]
             if directories:
                 yield 'd', util.normpath(s[common_prefix_len:]), os.lstat(s)
             while work:
                 top = work.pop()
                 names = os.listdir(top)
                 names.sort()
                 # nd is the top of the repository dir tree
                 nd = util.normpath(top[common_prefix_len:])
                 if nd == '.':
                     nd = ''
                 else:
                     # do not recurse into a repo contained in this
                     # one. use bisect to find .hg directory so speed
                     # is good on big directory.
                     hg = bisect.bisect_left(names, '.hg')
                     if hg < len(names) and names[hg] == '.hg':
                         if os.path.isdir(os.path.join(top, '.hg')):
                             continue
                 for f in names:
                     np = util.pconvert(os.path.join(nd, f))
                     if seen(np):
                         continue
                     p = os.path.join(top, f)
                     # don't trip over symlinks
                     st = os.lstat(p)
                     if stat.S_ISDIR(st.st_mode):
                         if not ignore(np):
                             work.append(p)
                             if directories:
                                 yield 'd', np, st
                         if imatch(np) and np in dc:
                             yield 'm', np, st
                     elif imatch(np):
                         if self.supported_type(np, st):
                             yield 'f', np, st
                         elif np in dc:
                             yield 'm', np, st
 
         known = {'.hg': 1}
         def seen(fn):
             if fn in known: return True
             known[fn] = 1
 
         # step one, find all files that match our criteria
         files.sort()
         for ff in files:
             nf = util.normpath(ff)
             f = self.wjoin(ff)
             try:
                 st = os.lstat(f)
             except OSError, inst:
                 found = False
                 for fn in dc:
                     if nf == fn or (fn.startswith(nf) and fn[len(nf)] == '/'):
                         found = True
                         break
                 if not found:
                     if inst.errno != errno.ENOENT or not badmatch:
                         self.ui.warn('%s: %s\n' % (
                             util.pathto(self.root, self.getcwd(), ff),
                             inst.strerror))
                     elif badmatch and badmatch(ff) and imatch(nf):
                         yield 'b', ff, None
                 continue
             if stat.S_ISDIR(st.st_mode):
                 cmp1 = (lambda x, y: cmp(x[1], y[1]))
                 sorted_ = [ x for x in findfiles(f) ]
                 sorted_.sort(cmp1)
                 for e in sorted_:
                     yield e
             else:
                 if not seen(nf) and match(nf):
                     if self.supported_type(ff, st, verbose=True):
                         yield 'f', nf, st
                     elif ff in dc:
                         yield 'm', nf, st
 
         # step two run through anything left in the dc hash and yield
         # if we haven't already seen it
         ks = dc.keys()
         ks.sort()
         for k in ks:
             if not seen(k) and imatch(k):
                 yield 'm', k, None
 
     def status(self, files=None, match=util.always, list_ignored=False,
                list_clean=False):
         lookup, modified, added, unknown, ignored = [], [], [], [], []
         removed, deleted, clean = [], [], []
 
         for src, fn, st in self.statwalk(files, match, ignored=list_ignored):
             try:
                 type_, mode, size, time = self[fn]
             except KeyError:
                 if list_ignored and self.ignore(fn):
                     ignored.append(fn)
                 else:
                     unknown.append(fn)
                 continue
             if src == 'm':
                 nonexistent = True
                 if not st:
                     try:
                         st = os.lstat(self.wjoin(fn))
                     except OSError, inst:
                         if inst.errno != errno.ENOENT:
                             raise
                         st = None
                     # We need to re-check that it is a valid file
                     if st and self.supported_type(fn, st):
                         nonexistent = False
                 # XXX: what to do with file no longer present in the fs
                 # who are not removed in the dirstate ?
                 if nonexistent and type_ in "nm":
                     deleted.append(fn)
                     continue
             # check the common case first
             if type_ == 'n':
                 if not st:
                     st = os.lstat(self.wjoin(fn))
                 if size >= 0 and (size != st.st_size
                                   or (mode ^ st.st_mode) & 0100):
                     modified.append(fn)
                 elif time != int(st.st_mtime):
                     lookup.append(fn)
                 elif list_clean:
                     clean.append(fn)
             elif type_ == 'm':
                 modified.append(fn)
             elif type_ == 'a':
                 added.append(fn)
             elif type_ == 'r':
                 removed.append(fn)
 
         return (lookup, modified, added, removed, deleted, unknown, ignored,
                 clean)