git binary patches: use hashes to detect identical files

mercurial/patch.py

@@ -1,682 +1,683
 # patch.py - patch file parsing routines
 #
 # Copyright 2006 Brendan Cully <[e-mail]>
 #
 # This software may be used and distributed according to the terms
 # of the GNU General Public License, incorporated herein by reference.
 
 from demandload import demandload
 from i18n import gettext as _
 from node import *
 demandload(globals(), "base85 cmdutil mdiff util")
 demandload(globals(), "cStringIO email.Parser errno os popen2 re shutil sha")
 demandload(globals(), "sys tempfile zlib")
 
 # helper functions
 
 def copyfile(src, dst, basedir=None):
     if not basedir:
         basedir = os.getcwd()
 
     abssrc, absdst = [os.path.join(basedir, n) for n in (src, dst)]
     if os.path.exists(absdst):
         raise util.Abort(_("cannot create %s: destination already exists") %
                          dst)
 
     targetdir = os.path.dirname(absdst)
     if not os.path.isdir(targetdir):
         os.makedirs(targetdir)
 
     util.copyfile(abssrc, absdst)
 
 # public functions
 
 def extract(ui, fileobj):
     '''extract patch from data read from fileobj.
 
     patch can be normal patch or contained in email message.
 
     return tuple (filename, message, user, date). any item in returned
     tuple can be None.  if filename is None, fileobj did not contain
     patch. caller must unlink filename when done.'''
 
     # attempt to detect the start of a patch
     # (this heuristic is borrowed from quilt)
     diffre = re.compile(r'^(?:Index:[ \t]|diff[ \t]|RCS file: |' +
                         'retrieving revision [0-9]+(\.[0-9]+)*$|' +
                         '(---|\*\*\*)[ \t])', re.MULTILINE)
 
     fd, tmpname = tempfile.mkstemp(prefix='hg-patch-')
     tmpfp = os.fdopen(fd, 'w')
     try:
         hgpatch = False
 
         msg = email.Parser.Parser().parse(fileobj)
 
         message = msg['Subject']
         user = msg['From']
         # should try to parse msg['Date']
         date = None
 
         if message:
             message = message.replace('\n\t', ' ')
             ui.debug('Subject: %s\n' % message)
         if user:
             ui.debug('From: %s\n' % user)
         diffs_seen = 0
         ok_types = ('text/plain', 'text/x-diff', 'text/x-patch')
 
         for part in msg.walk():
             content_type = part.get_content_type()
             ui.debug('Content-Type: %s\n' % content_type)
             if content_type not in ok_types:
                 continue
             payload = part.get_payload(decode=True)
             m = diffre.search(payload)
             if m:
                 ui.debug(_('found patch at byte %d\n') % m.start(0))
                 diffs_seen += 1
                 cfp = cStringIO.StringIO()
                 if message:
                     cfp.write(message)
                     cfp.write('\n')
                 for line in payload[:m.start(0)].splitlines():
                     if line.startswith('# HG changeset patch'):
                         ui.debug(_('patch generated by hg export\n'))
                         hgpatch = True
                         # drop earlier commit message content
                         cfp.seek(0)
                         cfp.truncate()
                     elif hgpatch:
                         if line.startswith('# User '):
                             user = line[7:]
                             ui.debug('From: %s\n' % user)
                         elif line.startswith("# Date "):
                             date = line[7:]
                     if not line.startswith('# '):
                         cfp.write(line)
                         cfp.write('\n')
                 message = cfp.getvalue()
                 if tmpfp:
                     tmpfp.write(payload)
                     if not payload.endswith('\n'):
                         tmpfp.write('\n')
             elif not diffs_seen and message and content_type == 'text/plain':
                 message += '\n' + payload
     except:
         tmpfp.close()
         os.unlink(tmpname)
         raise
 
     tmpfp.close()
     if not diffs_seen:
         os.unlink(tmpname)
         return None, message, user, date
     return tmpname, message, user, date
 
 GP_PATCH  = 1 << 0  # we have to run patch
 GP_FILTER = 1 << 1  # there's some copy/rename operation
 GP_BINARY = 1 << 2  # there's a binary patch
 
 def readgitpatch(patchname):
     """extract git-style metadata about patches from <patchname>"""
     class gitpatch:
         "op is one of ADD, DELETE, RENAME, MODIFY or COPY"
         def __init__(self, path):
             self.path = path
             self.oldpath = None
             self.mode = None
             self.op = 'MODIFY'
             self.copymod = False
             self.lineno = 0
             self.binary = False
 
     # Filter patch for git information
     gitre = re.compile('diff --git a/(.*) b/(.*)')
     pf = file(patchname)
     gp = None
     gitpatches = []
     # Can have a git patch with only metadata, causing patch to complain
     dopatch = 0
 
     lineno = 0
     for line in pf:
         lineno += 1
         if line.startswith('diff --git'):
             m = gitre.match(line)
             if m:
                 if gp:
                     gitpatches.append(gp)
                 src, dst = m.group(1, 2)
                 gp = gitpatch(dst)
                 gp.lineno = lineno
         elif gp:
             if line.startswith('--- '):
                 if gp.op in ('COPY', 'RENAME'):
                     gp.copymod = True
                     dopatch |= GP_FILTER
                 gitpatches.append(gp)
                 gp = None
                 dopatch |= GP_PATCH
                 continue
             if line.startswith('rename from '):
                 gp.op = 'RENAME'
                 gp.oldpath = line[12:].rstrip()
             elif line.startswith('rename to '):
                 gp.path = line[10:].rstrip()
             elif line.startswith('copy from '):
                 gp.op = 'COPY'
                 gp.oldpath = line[10:].rstrip()
             elif line.startswith('copy to '):
                 gp.path = line[8:].rstrip()
             elif line.startswith('deleted file'):
                 gp.op = 'DELETE'
             elif line.startswith('new file mode '):
                 gp.op = 'ADD'
                 gp.mode = int(line.rstrip()[-3:], 8)
             elif line.startswith('new mode '):
                 gp.mode = int(line.rstrip()[-3:], 8)
             elif line.startswith('GIT binary patch'):
                 dopatch |= GP_BINARY
                 gp.binary = True
     if gp:
         gitpatches.append(gp)
 
     if not gitpatches:
         dopatch = GP_PATCH
 
     return (dopatch, gitpatches)
 
 def dogitpatch(patchname, gitpatches, cwd=None):
     """Preprocess git patch so that vanilla patch can handle it"""
     def extractbin(fp):
         i = [0] # yuck
         def readline():
             i[0] += 1
             return fp.readline().rstrip()
         line = readline()
         while line and not line.startswith('literal '):
             line = readline()
         if not line:
             return None, i[0]
         size = int(line[8:])
         dec = []
         line = readline()
         while line:
             l = line[0]
             if l <= 'Z' and l >= 'A':
                 l = ord(l) - ord('A') + 1
             else:
                 l = ord(l) - ord('a') + 27
             dec.append(base85.b85decode(line[1:])[:l])
             line = readline()
         text = zlib.decompress(''.join(dec))
         if len(text) != size:
             raise util.Abort(_('binary patch is %d bytes, not %d') %
                              (len(text), size))
         return text, i[0]
 
     pf = file(patchname)
     pfline = 1
 
     fd, patchname = tempfile.mkstemp(prefix='hg-patch-')
     tmpfp = os.fdopen(fd, 'w')
 
     try:
         for i in xrange(len(gitpatches)):
             p = gitpatches[i]
             if not p.copymod and not p.binary:
                 continue
 
             # rewrite patch hunk
             while pfline < p.lineno:
                 tmpfp.write(pf.readline())
                 pfline += 1
 
             if p.binary:
                 text, delta = extractbin(pf)
                 if not text:
                     raise util.Abort(_('binary patch extraction failed'))
                 pfline += delta
                 if not cwd:
                     cwd = os.getcwd()
                 absdst = os.path.join(cwd, p.path)
                 basedir = os.path.dirname(absdst)
                 if not os.path.isdir(basedir):
                     os.makedirs(basedir)
                 out = file(absdst, 'wb')
                 out.write(text)
                 out.close()
             elif p.copymod:
                 copyfile(p.oldpath, p.path, basedir=cwd)
                 tmpfp.write('diff --git a/%s b/%s\n' % (p.path, p.path))
                 line = pf.readline()
                 pfline += 1
                 while not line.startswith('--- a/'):
                     tmpfp.write(line)
                     line = pf.readline()
                     pfline += 1
                 tmpfp.write('--- a/%s\n' % p.path)
 
         line = pf.readline()
         while line:
             tmpfp.write(line)
             line = pf.readline()
     except:
         tmpfp.close()
         os.unlink(patchname)
         raise
 
     tmpfp.close()
     return patchname
 
 def patch(patchname, ui, strip=1, cwd=None, files={}):
     """apply the patch <patchname> to the working directory.
     a list of patched files is returned"""
 
     # helper function
     def __patch(patchname):
         """patch and updates the files and fuzz variables"""
         fuzz = False
 
         patcher = util.find_in_path('gpatch', os.environ.get('PATH', ''),
                                     'patch')
         args = []
         if cwd:
             args.append('-d %s' % util.shellquote(cwd))
         fp = os.popen('%s %s -p%d < %s' % (patcher, ' '.join(args), strip,
                                            util.shellquote(patchname)))
 
         for line in fp:
             line = line.rstrip()
             ui.note(line + '\n')
             if line.startswith('patching file '):
                 pf = util.parse_patch_output(line)
                 printed_file = False
                 files.setdefault(pf, (None, None))
             elif line.find('with fuzz') >= 0:
                 fuzz = True
                 if not printed_file:
                     ui.warn(pf + '\n')
                     printed_file = True
                 ui.warn(line + '\n')
             elif line.find('saving rejects to file') >= 0:
                 ui.warn(line + '\n')
             elif line.find('FAILED') >= 0:
                 if not printed_file:
                     ui.warn(pf + '\n')
                     printed_file = True
                 ui.warn(line + '\n')
         code = fp.close()
         if code:
             raise util.Abort(_("patch command failed: %s") %
                              util.explain_exit(code)[0])
         return fuzz
 
     (dopatch, gitpatches) = readgitpatch(patchname)
     for gp in gitpatches:
         files[gp.path] = (gp.op, gp)
 
     fuzz = False
     if dopatch:
         filterpatch = dopatch & (GP_FILTER | GP_BINARY)
         if filterpatch:
             patchname = dogitpatch(patchname, gitpatches, cwd=cwd)
         try:
             if dopatch & GP_PATCH:
                 fuzz = __patch(patchname)
         finally:
             if filterpatch:
                 os.unlink(patchname)
 
     return fuzz
 
 def diffopts(ui, opts={}, untrusted=False):
     def get(key, name=None):
         return (opts.get(key) or
                 ui.configbool('diff', name or key, None, untrusted=untrusted))
     return mdiff.diffopts(
         text=opts.get('text'),
         git=get('git'),
         nodates=get('nodates'),
         showfunc=get('show_function', 'showfunc'),
         ignorews=get('ignore_all_space', 'ignorews'),
         ignorewsamount=get('ignore_space_change', 'ignorewsamount'),
         ignoreblanklines=get('ignore_blank_lines', 'ignoreblanklines'))
 
 def updatedir(ui, repo, patches, wlock=None):
     '''Update dirstate after patch application according to metadata'''
     if not patches:
         return
     copies = []
     removes = {}
     cfiles = patches.keys()
     cwd = repo.getcwd()
     if cwd:
         cfiles = [util.pathto(cwd, f) for f in patches.keys()]
     for f in patches:
         ctype, gp = patches[f]
         if ctype == 'RENAME':
             copies.append((gp.oldpath, gp.path, gp.copymod))
             removes[gp.oldpath] = 1
         elif ctype == 'COPY':
             copies.append((gp.oldpath, gp.path, gp.copymod))
         elif ctype == 'DELETE':
             removes[gp.path] = 1
     for src, dst, after in copies:
         if not after:
             copyfile(src, dst, repo.root)
         repo.copy(src, dst, wlock=wlock)
     removes = removes.keys()
     if removes:
         removes.sort()
         repo.remove(removes, True, wlock=wlock)
     for f in patches:
         ctype, gp = patches[f]
         if gp and gp.mode:
             x = gp.mode & 0100 != 0
             dst = os.path.join(repo.root, gp.path)
             # patch won't create empty files
             if ctype == 'ADD' and not os.path.exists(dst):
                 repo.wwrite(gp.path, '')
             util.set_exec(dst, x)
     cmdutil.addremove(repo, cfiles, wlock=wlock)
     files = patches.keys()
     files.extend([r for r in removes if r not in files])
     files.sort()
 
     return files
 
 def b85diff(fp, to, tn):
     '''print base85-encoded binary diff'''
     def gitindex(text):
         if not text:
             return '0' * 40
         l = len(text)
         s = sha.new('blob %d\0' % l)
         s.update(text)
         return s.hexdigest()
 
     def fmtline(line):
         l = len(line)
         if l <= 26:
             l = chr(ord('A') + l - 1)
         else:
             l = chr(l - 26 + ord('a') - 1)
         return '%c%s\n' % (l, base85.b85encode(line, True))
 
     def chunk(text, csize=52):
         l = len(text)
         i = 0
         while i < l:
             yield text[i:i+csize]
             i += csize
 
-    if to == tn:
+    tohash = gitindex(to)
+    tnhash = gitindex(tn)
+    if tohash == tnhash:
         return
     # TODO: deltas
-    l = len(tn)
     fp.write('index %s..%s\nGIT binary patch\nliteral %s\n' %
-             (gitindex(to), gitindex(tn), len(tn)))
+             (tohash, tnhash, len(tn)))
 
     tn = ''.join([fmtline(l) for l in chunk(zlib.compress(tn))])
     fp.write(tn)
     fp.write('\n')
 
 def diff(repo, node1=None, node2=None, files=None, match=util.always,
          fp=None, changes=None, opts=None):
     '''print diff of changes to files between two nodes, or node and
     working directory.
 
     if node1 is None, use first dirstate parent instead.
     if node2 is None, compare node1 with working directory.'''
 
     if opts is None:
         opts = mdiff.defaultopts
     if fp is None:
         fp = repo.ui
 
     if not node1:
         node1 = repo.dirstate.parents()[0]
 
     clcache = {}
     def getchangelog(n):
         if n not in clcache:
             clcache[n] = repo.changelog.read(n)
         return clcache[n]
     mcache = {}
     def getmanifest(n):
         if n not in mcache:
             mcache[n] = repo.manifest.read(n)
         return mcache[n]
     fcache = {}
     def getfile(f):
         if f not in fcache:
             fcache[f] = repo.file(f)
         return fcache[f]
 
     # reading the data for node1 early allows it to play nicely
     # with repo.status and the revlog cache.
     change = getchangelog(node1)
     mmap = getmanifest(change[0])
     date1 = util.datestr(change[2])
 
     if not changes:
         changes = repo.status(node1, node2, files, match=match)[:5]
     modified, added, removed, deleted, unknown = changes
     if files:
         def filterfiles(filters):
             l = [x for x in filters if x in files]
 
             for t in files:
                 if not t.endswith("/"):
                     t += "/"
                 l += [x for x in filters if x.startswith(t)]
             return l
 
         modified, added, removed = map(filterfiles, (modified, added, removed))
 
     if not modified and not added and not removed:
         return
 
     # returns False if there was no rename between n1 and n2
     # returns None if the file was created between n1 and n2
     # returns the (file, node) present in n1 that was renamed to f in n2
     def renamedbetween(f, n1, n2):
         r1, r2 = map(repo.changelog.rev, (n1, n2))
         orig = f
         src = None
         while r2 > r1:
             cl = getchangelog(n2)
             if f in cl[3]:
                 m = getmanifest(cl[0])
                 try:
                     src = getfile(f).renamed(m[f])
                 except KeyError:
                     return None
                 if src:
                     f = src[0]
             n2 = repo.changelog.parents(n2)[0]
             r2 = repo.changelog.rev(n2)
         cl = getchangelog(n1)
         m = getmanifest(cl[0])
         if f not in m:
             return None
         if f == orig:
             return False
         return f, m[f]
 
     if node2:
         change = getchangelog(node2)
         mmap2 = getmanifest(change[0])
         _date2 = util.datestr(change[2])
         def date2(f):
             return _date2
         def read(f):
             return getfile(f).read(mmap2[f])
         def renamed(f):
             return renamedbetween(f, node1, node2)
     else:
         tz = util.makedate()[1]
         _date2 = util.datestr()
         def date2(f):
             try:
                 return util.datestr((os.lstat(repo.wjoin(f)).st_mtime, tz))
             except OSError, err:
                 if err.errno != errno.ENOENT: raise
                 return _date2
         def read(f):
             return repo.wread(f)
         def renamed(f):
             src = repo.dirstate.copied(f)
             parent = repo.dirstate.parents()[0]
             if src:
                 f = src
             of = renamedbetween(f, node1, parent)
             if of or of is None:
                 return of
             elif src:
                 cl = getchangelog(parent)[0]
                 return (src, getmanifest(cl)[src])
             else:
                 return None
 
     if repo.ui.quiet:
         r = None
     else:
         hexfunc = repo.ui.debugflag and hex or short
         r = [hexfunc(node) for node in [node1, node2] if node]
 
     if opts.git:
         copied = {}
         for f in added:
             src = renamed(f)
             if src:
                 copied[f] = src
         srcs = [x[1][0] for x in copied.items()]
 
     all = modified + added + removed
     all.sort()
     gone = {}
     for f in all:
         to = None
         tn = None
         dodiff = True
         header = []
         if f in mmap:
             to = getfile(f).read(mmap[f])
         if f not in removed:
             tn = read(f)
         if opts.git:
             def gitmode(x):
                 return x and '100755' or '100644'
             def addmodehdr(header, omode, nmode):
                 if omode != nmode:
                     header.append('old mode %s\n' % omode)
                     header.append('new mode %s\n' % nmode)
 
             a, b = f, f
             if f in added:
                 if node2:
                     mode = gitmode(mmap2.execf(f))
                 else:
                     mode = gitmode(util.is_exec(repo.wjoin(f), None))
                 if f in copied:
                     a, arev = copied[f]
                     omode = gitmode(mmap.execf(a))
                     addmodehdr(header, omode, mode)
                     if a in removed and a not in gone:
                         op = 'rename'
                         gone[a] = 1
                     else:
                         op = 'copy'
                     header.append('%s from %s\n' % (op, a))
                     header.append('%s to %s\n' % (op, f))
                     to = getfile(a).read(arev)
                 else:
                     header.append('new file mode %s\n' % mode)
                 if util.binary(tn):
                     dodiff = 'binary'
             elif f in removed:
                 if f in srcs:
                     dodiff = False
                 else:
                     mode = gitmode(mmap.execf(f))
                     header.append('deleted file mode %s\n' % mode)
             else:
                 omode = gitmode(mmap.execf(f))
                 if node2:
                     nmode = gitmode(mmap2.execf(f))
                 else:
                     nmode = gitmode(util.is_exec(repo.wjoin(f), mmap.execf(f)))
                 addmodehdr(header, omode, nmode)
                 if util.binary(to) or util.binary(tn):
                     dodiff = 'binary'
             r = None
             header.insert(0, 'diff --git a/%s b/%s\n' % (a, b))
         if dodiff == 'binary':
             fp.write(''.join(header))
             b85diff(fp, to, tn)
         elif dodiff:
             text = mdiff.unidiff(to, date1, tn, date2(f), f, r, opts=opts)
             if text or len(header) > 1:
                 fp.write(''.join(header))
             fp.write(text)
 
 def export(repo, revs, template='hg-%h.patch', fp=None, switch_parent=False,
            opts=None):
     '''export changesets as hg patches.'''
 
     total = len(revs)
     revwidth = max([len(str(rev)) for rev in revs])
 
     def single(node, seqno, fp):
         parents = [p for p in repo.changelog.parents(node) if p != nullid]
         if switch_parent:
             parents.reverse()
         prev = (parents and parents[0]) or nullid
         change = repo.changelog.read(node)
 
         if not fp:
             fp = cmdutil.make_file(repo, template, node, total=total,
                                    seqno=seqno, revwidth=revwidth)
         if fp not in (sys.stdout, repo.ui):
             repo.ui.note("%s\n" % fp.name)
 
         fp.write("# HG changeset patch\n")
         fp.write("# User %s\n" % change[1])
         fp.write("# Date %d %d\n" % change[2])
         fp.write("# Node ID %s\n" % hex(node))
         fp.write("# Parent  %s\n" % hex(prev))
         if len(parents) > 1:
             fp.write("# Parent  %s\n" % hex(parents[1]))
         fp.write(change[4].rstrip())
         fp.write("\n\n")
 
         diff(repo, prev, node, fp=fp, opts=opts)
         if fp not in (sys.stdout, repo.ui):
             fp.close()
 
     for seqno, rev in enumerate(revs):
         single(repo.lookup(rev), seqno+1, fp)
 
 def diffstat(patchlines):
     fd, name = tempfile.mkstemp(prefix="hg-patchbomb-", suffix=".txt")
     try:
         p = popen2.Popen3('diffstat -p1 -w79 2>/dev/null > ' + name)
         try:
             for line in patchlines: print >> p.tochild, line
             p.tochild.close()
             if p.wait(): return
             fp = os.fdopen(fd, 'r')
             stat = []
             for line in fp: stat.append(line.lstrip())
             last = stat.pop()
             stat.insert(0, last)
             stat = ''.join(stat)
             if stat.startswith('0 files'): raise ValueError
             return stat
         except: raise
     finally:
         try: os.unlink(name)
         except: pass