hg-fast-export.py

   1 #!/usr/bin/env python
   2
   3 # Copyright (c) 2007, 2008 Rocco Rutte <pdmef@gmx.net> and others.
   4 # License: MIT <http://www.opensource.org/licenses/mit-license.php>
   5
   6 from mercurial import node
   7 from hg2git import setup_repo,fixup_user,get_branch,get_changeset
   8 from hg2git import load_cache,save_cache,get_git_sha1,set_default_branch,set_origin_name
   9 from optparse import OptionParser
  10 import re
  11 import sys
  12 import os
  13
  14 if sys.platform == "win32":
  15   # On Windows, sys.stdout is initially opened in text mode, which means that
  16   # when a LF (\n) character is written to sys.stdout, it will be converted
  17   # into CRLF (\r\n).  That makes git blow up, so use this platform-specific
  18   # code to change the mode of sys.stdout to binary.
  19   import msvcrt
  20   msvcrt.setmode(sys.stdout.fileno(), os.O_BINARY)
  21
  22 # silly regex to catch Signed-off-by lines in log message
  23 sob_re=re.compile('^Signed-[Oo]ff-[Bb]y: (.+)$')
  24 # insert 'checkpoint' command after this many commits or none at all if 0
  25 cfg_checkpoint_count=0
  26 # write some progress message every this many file contents written
  27 cfg_export_boundary=1000
  28
  29 def gitmode(flags):
  30   return 'l' in flags and '120000' or 'x' in flags and '100755' or '100644'
  31
  32 def wr(msg=''):
  33   if msg:
  34     sys.stdout.write(msg)
  35   sys.stdout.write('\n')
  36   #map(lambda x: sys.stderr.write('\t[%s]\n' % x),msg.split('\n'))
  37
  38 def checkpoint(count):
  39   count=count+1
  40   if cfg_checkpoint_count>0 and count%cfg_checkpoint_count==0:
  41     sys.stderr.write("Checkpoint after %d commits\n" % count)
  42     wr('checkpoint')
  43     wr()
  44   return count
  45
  46 def revnum_to_revref(rev, old_marks):
  47   """Convert an hg revnum to a git-fast-import rev reference (an SHA1
  48   or a mark)"""
  49   return old_marks.get(rev) or ':%d' % (rev+1)
  50
  51 def file_mismatch(f1,f2):
  52   """See if two revisions of a file are not equal."""
  53   return node.hex(f1)!=node.hex(f2)
  54
  55 def split_dict(dleft,dright,l=[],c=[],r=[],match=file_mismatch):
  56   """Loop over our repository and find all changed and missing files."""
  57   for left in dleft.keys():
  58     right=dright.get(left,None)
  59     if right==None:
  60       # we have the file but our parent hasn't: add to left set
  61       l.append(left)
  62     elif match(dleft[left],right):
  63       # we have it but checksums mismatch: add to center set
  64       c.append(left)
  65   for right in dright.keys():
  66     left=dleft.get(right,None)
  67     if left==None:
  68       # if parent has file but we don't: add to right set
  69       r.append(right)
  70     # change is already handled when comparing child against parent
  71   return l,c,r
  72
  73 def get_filechanges(repo,revision,parents,mleft):
  74   """Given some repository and revision, find all changed/deleted files."""
  75   l,c,r=[],[],[]
  76   for p in parents:
  77     if p<0: continue
  78     mright=repo.changectx(p).manifest()
  79     l,c,r=split_dict(mleft,mright,l,c,r)
  80   l.sort()
  81   c.sort()
  82   r.sort()
  83   return l,c,r
  84
  85 def get_author(logmessage,committer,authors):
  86   """As git distincts between author and committer of a patch, try to
  87   extract author by detecting Signed-off-by lines.
  88
  89   This walks from the end of the log message towards the top skipping
  90   empty lines. Upon the first non-empty line, it walks all Signed-off-by
  91   lines upwards to find the first one. For that (if found), it extracts
  92   authorship information the usual way (authors table, cleaning, etc.)
  93
  94   If no Signed-off-by line is found, this defaults to the committer.
  95
  96   This may sound stupid (and it somehow is), but in log messages we
  97   accidentially may have lines in the middle starting with
  98   "Signed-off-by: foo" and thus matching our detection regex. Prevent
  99   that."""
 100
 101   loglines=logmessage.split('\n')
 102   i=len(loglines)
 103   # from tail walk to top skipping empty lines
 104   while i>=0:
 105     i-=1
 106     if len(loglines[i].strip())==0: continue
 107     break
 108   if i>=0:
 109     # walk further upwards to find first sob line, store in 'first'
 110     first=None
 111     while i>=0:
 112       m=sob_re.match(loglines[i])
 113       if m==None: break
 114       first=m
 115       i-=1
 116     # if the last non-empty line matches our Signed-Off-by regex: extract username
 117     if first!=None:
 118       r=fixup_user(first.group(1),authors)
 119       return r
 120   return committer
 121
 122 def export_file_contents(ctx,manifest,files):
 123   count=0
 124   max=len(files)
 125   for file in files:
 126     # Skip .hgtags files. They only get us in trouble.
 127     if file == ".hgtags":
 128       sys.stderr.write('Skip %s\n' % (file))
 129       continue
 130     d=ctx.filectx(file).data()
 131     wr('M %s inline %s' % (gitmode(manifest.flags(file)),file))
 132     wr('data %d' % len(d)) # had some trouble with size()
 133     wr(d)
 134     count+=1
 135     if count%cfg_export_boundary==0:
 136       sys.stderr.write('Exported %d/%d files\n' % (count,max))
 137   if max>cfg_export_boundary:
 138     sys.stderr.write('Exported %d/%d files\n' % (count,max))
 139
 140 def sanitize_name(name,what="branch"):
 141   """Sanitize input roughly according to git-check-ref-format(1)"""
 142
 143   def dot(name):
 144     if name[0] == '.': return '_'+name[1:]
 145     return name
 146
 147   n=name
 148   p=re.compile('([[ ~^:?*]|\.\.)')
 149   n=p.sub('_', n)
 150   if n[-1] in ('/', '.'): n=n[:-1]+'_'
 151   n='/'.join(map(dot,n.split('/')))
 152   p=re.compile('_+')
 153   n=p.sub('_', n)
 154
 155   if n!=name:
 156     sys.stderr.write('Warning: sanitized %s [%s] to [%s]\n' % (what,name,n))
 157   return n
 158
 159 def export_commit(ui,repo,revision,old_marks,max,count,authors,sob,brmap):
 160   def get_branchname(name):
 161     if brmap.has_key(name):
 162       return brmap[name]
 163     n=sanitize_name(name)
 164     brmap[name]=n
 165     return n
 166
 167   (revnode,_,user,(time,timezone),files,desc,branch,_)=get_changeset(ui,repo,revision,authors)
 168
 169   branch=get_branchname(branch)
 170
 171   parents = [p for p in repo.changelog.parentrevs(revision) if p >= 0]
 172
 173   if len(parents)==0 and revision != 0:
 174     wr('reset refs/heads/%s' % branch)
 175
 176   wr('commit refs/heads/%s' % branch)
 177   wr('mark :%d' % (revision+1))
 178   if sob:
 179     wr('author %s %d %s' % (get_author(desc,user,authors),time,timezone))
 180   wr('committer %s %d %s' % (user,time,timezone))
 181   wr('data %d' % (len(desc)+1)) # wtf?
 182   wr(desc)
 183   wr()
 184
 185
 186   # Sort the parents based on revision ids so that we always get the
 187   # same resulting git repo, no matter how the revisions were
 188   # numbered.
 189   parents.sort(key=repo.changelog.node, reverse=True)
 190
 191   ctx=repo.changectx(str(revision))
 192   man=ctx.manifest()
 193   added,changed,removed,type=[],[],[],''
 194
 195   if len(parents) == 0:
 196     # first revision: feed in full manifest
 197     added=man.keys()
 198     added.sort()
 199     type='full'
 200   else:
 201     wr('from %s' % revnum_to_revref(parents[0], old_marks))
 202     if len(parents) == 1:
 203       # later non-merge revision: feed in changed manifest
 204       # if we have exactly one parent, just take the changes from the
 205       # manifest without expensively comparing checksums
 206       f=repo.status(repo.lookup(parents[0]),revnode)[:3]
 207       added,changed,removed=f[1],f[0],f[2]
 208       type='simple delta'
 209     else: # a merge with two parents
 210       wr('merge %s' % revnum_to_revref(parents[1], old_marks))
 211       # later merge revision: feed in changed manifest
 212       # for many files comparing checksums is expensive so only do it for
 213       # merges where we really need it due to hg's revlog logic
 214       added,changed,removed=get_filechanges(repo,revision,parents,man)
 215       type='thorough delta'
 216
 217   sys.stderr.write('%s: Exporting %s revision %d/%d with %d/%d/%d added/changed/removed files\n' %
 218       (branch,type,revision+1,max,len(added),len(changed),len(removed)))
 219
 220   map(lambda r: wr('D %s' % r),removed)
 221   export_file_contents(ctx,man,added)
 222   export_file_contents(ctx,man,changed)
 223   wr()
 224
 225   return checkpoint(count)
 226
 227 def export_tags(ui,repo,old_marks,mapping_cache,count,authors):
 228   l=repo.tagslist()
 229   for tag,node in l:
 230     tag=sanitize_name(tag,"tag")
 231     # ignore latest revision
 232     if tag=='tip': continue
 233     # ignore tags to nodes that are missing (ie, 'in the future')
 234     if node.encode('hex_codec') not in mapping_cache:
 235       sys.stderr.write('Tag %s refers to unseen node %s\n' % (tag, node.encode('hex_codec')))
 236       continue
 237
 238     rev=int(mapping_cache[node.encode('hex_codec')])
 239
 240     ref=revnum_to_revref(rev, old_marks)
 241     if ref==None:
 242       sys.stderr.write('Failed to find reference for creating tag'
 243           ' %s at r%d\n' % (tag,rev))
 244       continue
 245     sys.stderr.write('Exporting tag [%s] at [hg r%d] [git %s]\n' % (tag,rev,ref))
 246     wr('reset refs/tags/%s' % tag)
 247     wr('from %s' % ref)
 248     wr()
 249     count=checkpoint(count)
 250   return count
 251
 252 def load_authors(filename):
 253   cache={}
 254   if not os.path.exists(filename):
 255     return cache
 256   f=open(filename,'r')
 257   l=0
 258   lre=re.compile('^([^=]+)[ ]*=[ ]*(.+)$')
 259   for line in f.readlines():
 260     l+=1
 261     m=lre.match(line)
 262     if m==None:
 263       sys.stderr.write('Invalid file format in [%s], line %d\n' % (filename,l))
 264       continue
 265     # put key:value in cache, key without ^:
 266     cache[m.group(1).strip()]=m.group(2).strip()
 267   f.close()
 268   sys.stderr.write('Loaded %d authors\n' % l)
 269   return cache
 270
 271 def verify_heads(ui,repo,cache,force):
 272   branches=repo.branchtags()
 273   l=[(-repo.changelog.rev(n), n, t) for t, n in branches.items()]
 274   l.sort()
 275
 276   # get list of hg's branches to verify, don't take all git has
 277   for _,_,b in l:
 278     b=get_branch(b)
 279     sha1=get_git_sha1(b)
 280     c=cache.get(b)
 281     if sha1!=c:
 282       sys.stderr.write('Error: Branch [%s] modified outside hg-fast-export:'
 283         '\n%s (repo) != %s (cache)\n' % (b,sha1,c))
 284       if not force: return False
 285
 286   # verify that branch has exactly one head
 287   t={}
 288   for h in repo.heads():
 289     (_,_,_,_,_,_,branch,_)=get_changeset(ui,repo,h)
 290     if t.get(branch,False):
 291       sys.stderr.write('Error: repository has at least one unnamed head: hg r%s\n' %
 292           repo.changelog.rev(h))
 293       if not force: return False
 294     t[branch]=True
 295
 296   return True
 297
 298 def hg2git(repourl,m,marksfile,mappingfile,headsfile,tipfile,authors={},sob=False,force=False):
 299   _max=int(m)
 300
 301   old_marks=load_cache(marksfile,lambda s: int(s)-1)
 302   mapping_cache=load_cache(mappingfile)
 303   heads_cache=load_cache(headsfile)
 304   state_cache=load_cache(tipfile)
 305
 306   ui,repo=setup_repo(repourl)
 307
 308   if not verify_heads(ui,repo,heads_cache,force):
 309     return 1
 310
 311   try:
 312     tip=repo.changelog.count()
 313   except AttributeError:
 314     tip=len(repo)
 315
 316   min=int(state_cache.get('tip',0))
 317   max=_max
 318   if _max<0 or max>tip:
 319     max=tip
 320
 321   for rev in range(0,max):
 322         (revnode,_,_,_,_,_,_,_)=get_changeset(ui,repo,rev,authors)
 323         mapping_cache[revnode.encode('hex_codec')] = str(rev)
 324
 325
 326   c=0
 327   brmap={}
 328   for rev in range(min,max):
 329     c=export_commit(ui,repo,rev,old_marks,max,c,authors,sob,brmap)
 330
 331   state_cache['tip']=max
 332   state_cache['repo']=repourl
 333   save_cache(tipfile,state_cache)
 334   save_cache(mappingfile,mapping_cache)
 335
 336   c=export_tags(ui,repo,old_marks,mapping_cache,c,authors)
 337
 338   sys.stderr.write('Issued %d commands\n' % c)
 339
 340   return 0
 341
 342 if __name__=='__main__':
 343   def bail(parser,opt):
 344     sys.stderr.write('Error: No %s option given\n' % opt)
 345     parser.print_help()
 346     sys.exit(2)
 347
 348   parser=OptionParser()
 349
 350   parser.add_option("-m","--max",type="int",dest="max",
 351       help="Maximum hg revision to import")
 352   parser.add_option("--mapping",dest="mappingfile",
 353       help="File to read last run's hg-to-git SHA1 mapping")
 354   parser.add_option("--marks",dest="marksfile",
 355       help="File to read git-fast-import's marks from")
 356   parser.add_option("--heads",dest="headsfile",
 357       help="File to read last run's git heads from")
 358   parser.add_option("--status",dest="statusfile",
 359       help="File to read status from")
 360   parser.add_option("-r","--repo",dest="repourl",
 361       help="URL of repo to import")
 362   parser.add_option("-s",action="store_true",dest="sob",
 363       default=False,help="Enable parsing Signed-off-by lines")
 364   parser.add_option("-A","--authors",dest="authorfile",
 365       help="Read authormap from AUTHORFILE")
 366   parser.add_option("-f","--force",action="store_true",dest="force",
 367       default=False,help="Ignore validation errors by force")
 368   parser.add_option("-M","--default-branch",dest="default_branch",
 369       help="Set the default branch")
 370   parser.add_option("-o","--origin",dest="origin_name",
 371       help="use <name> as namespace to track upstream")
 372
 373   (options,args)=parser.parse_args()
 374
 375   m=-1
 376   if options.max!=None: m=options.max
 377
 378   if options.marksfile==None: bail(parser,'--marks')
 379   if options.mappingfile==None: bail(parser,'--mapping')
 380   if options.headsfile==None: bail(parser,'--heads')
 381   if options.statusfile==None: bail(parser,'--status')
 382   if options.repourl==None: bail(parser,'--repo')
 383
 384   a={}
 385   if options.authorfile!=None:
 386     a=load_authors(options.authorfile)
 387
 388   if options.default_branch!=None:
 389     set_default_branch(options.default_branch)
 390
 391   if options.origin_name!=None:
 392     set_origin_name(options.origin_name)
 393
 394   sys.exit(hg2git(options.repourl,m,options.marksfile,options.mappingfile,options.headsfile,
 395     options.statusfile,authors=a,sob=options.sob,force=options.force))