Documentation/SubmittingPatches: Gnus tips
[git] / git-fetch.sh
1 #!/bin/sh
2 #
3
4 USAGE='<fetch-options> <repository> <refspec>...'
5 SUBDIRECTORY_OK=Yes
6 . git-sh-setup
7 set_reflog_action "fetch $*"
8 cd_to_toplevel ;# probably unnecessary...
9
10 . git-parse-remote
11 _x40='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
12 _x40="$_x40$_x40$_x40$_x40$_x40$_x40$_x40$_x40"
13
14 LF='
15 '
16 IFS="$LF"
17
18 no_tags=
19 tags=
20 append=
21 force=
22 verbose=
23 update_head_ok=
24 exec=
25 upload_pack=
26 keep=
27 shallow_depth=
28 while case "$#" in 0) break ;; esac
29 do
30         case "$1" in
31         -a|--a|--ap|--app|--appe|--appen|--append)
32                 append=t
33                 ;;
34         --upl|--uplo|--uploa|--upload|--upload-|--upload-p|\
35         --upload-pa|--upload-pac|--upload-pack)
36                 shift
37                 exec="--exec=$1" 
38                 upload_pack="-u $1"
39                 ;;
40         -f|--f|--fo|--for|--forc|--force)
41                 force=t
42                 ;;
43         -t|--t|--ta|--tag|--tags)
44                 tags=t
45                 ;;
46         -n|--n|--no|--no-|--no-t|--no-ta|--no-tag|--no-tags)
47                 no_tags=t
48                 ;;
49         -u|--u|--up|--upd|--upda|--updat|--update|--update-|--update-h|\
50         --update-he|--update-hea|--update-head|--update-head-|\
51         --update-head-o|--update-head-ok)
52                 update_head_ok=t
53                 ;;
54         -v|--verbose)
55                 verbose=Yes
56                 ;;
57         -k|--k|--ke|--kee|--keep)
58                 keep='-k -k'
59                 ;;
60         --depth=*)
61                 shallow_depth="--depth=`expr "z$1" : 'z-[^=]*=\(.*\)'`"
62                 ;;
63         --depth)
64                 shift
65                 shallow_depth="--depth=$1"
66                 ;;
67         -*)
68                 usage
69                 ;;
70         *)
71                 break
72                 ;;
73         esac
74         shift
75 done
76
77 case "$#" in
78 0)
79         origin=$(get_default_remote)
80         test -n "$(get_remote_url ${origin})" ||
81                 die "Where do you want to fetch from today?"
82         set x $origin ; shift ;;
83 esac
84
85 remote_nick="$1"
86 remote=$(get_remote_url "$@")
87 refs=
88 rref=
89 rsync_slurped_objects=
90
91 if test "" = "$append"
92 then
93         : >"$GIT_DIR/FETCH_HEAD"
94 fi
95
96 # Global that is reused later
97 ls_remote_result=$(git ls-remote $upload_pack "$remote") ||
98         die "Cannot get the repository state from $remote"
99
100 append_fetch_head () {
101     head_="$1"
102     remote_="$2"
103     remote_name_="$3"
104     remote_nick_="$4"
105     local_name_="$5"
106     case "$6" in
107     t) not_for_merge_='not-for-merge' ;;
108     '') not_for_merge_= ;;
109     esac
110
111     # remote-nick is the URL given on the command line (or a shorthand)
112     # remote-name is the $GIT_DIR relative refs/ path we computed
113     # for this refspec.
114
115     # the $note_ variable will be fed to git-fmt-merge-msg for further
116     # processing.
117     case "$remote_name_" in
118     HEAD)
119         note_= ;;
120     refs/heads/*)
121         note_="$(expr "$remote_name_" : 'refs/heads/\(.*\)')"
122         note_="branch '$note_' of " ;;
123     refs/tags/*)
124         note_="$(expr "$remote_name_" : 'refs/tags/\(.*\)')"
125         note_="tag '$note_' of " ;;
126     refs/remotes/*)
127         note_="$(expr "$remote_name_" : 'refs/remotes/\(.*\)')"
128         note_="remote branch '$note_' of " ;;
129     *)
130         note_="$remote_name of " ;;
131     esac
132     remote_1_=$(expr "z$remote_" : 'z\(.*\)\.git/*$') &&
133         remote_="$remote_1_"
134     note_="$note_$remote_"
135
136     # 2.6.11-tree tag would not be happy to be fed to resolve.
137     if git-cat-file commit "$head_" >/dev/null 2>&1
138     then
139         headc_=$(git-rev-parse --verify "$head_^0") || exit
140         echo "$headc_   $not_for_merge_ $note_" >>"$GIT_DIR/FETCH_HEAD"
141     else
142         echo "$head_    not-for-merge   $note_" >>"$GIT_DIR/FETCH_HEAD"
143     fi
144
145     update_local_ref "$local_name_" "$head_" "$note_"
146 }
147
148 update_local_ref () {
149     # If we are storing the head locally make sure that it is
150     # a fast forward (aka "reverse push").
151
152     label_=$(git-cat-file -t $2)
153     newshort_=$(git-rev-parse --short $2)
154     if test -z "$1" ; then
155         [ "$verbose" ] && echo >&2 "* fetched $3"
156         [ "$verbose" ] && echo >&2 "  $label_: $newshort_"
157         return 0
158     fi
159     oldshort_=$(git show-ref --hash --abbrev "$1" 2>/dev/null)
160
161     case "$1" in
162     refs/tags/*)
163         # Tags need not be pointing at commits so there
164         # is no way to guarantee "fast-forward" anyway.
165         if test -n "$oldshort_"
166         then
167                 if now_=$(git show-ref --hash "$1") && test "$now_" = "$2"
168                 then
169                         [ "$verbose" ] && echo >&2 "* $1: same as $3"
170                         [ "$verbose" ] && echo >&2 "  $label_: $newshort_" ||:
171                 else
172                         echo >&2 "* $1: updating with $3"
173                         echo >&2 "  $label_: $newshort_"
174                         git-update-ref -m "$GIT_REFLOG_ACTION: updating tag" "$1" "$2"
175                 fi
176         else
177                 echo >&2 "* $1: storing $3"
178                 echo >&2 "  $label_: $newshort_"
179                 git-update-ref -m "$GIT_REFLOG_ACTION: storing tag" "$1" "$2"
180         fi
181         ;;
182
183     refs/heads/* | refs/remotes/*)
184         # $1 is the ref being updated.
185         # $2 is the new value for the ref.
186         local=$(git-rev-parse --verify "$1^0" 2>/dev/null)
187         if test "$local"
188         then
189             # Require fast-forward.
190             mb=$(git-merge-base "$local" "$2") &&
191             case "$2,$mb" in
192             $local,*)
193                 if test -n "$verbose"
194                 then
195                         echo >&2 "* $1: same as $3"
196                         echo >&2 "  $label_: $newshort_"
197                 fi
198                 ;;
199             *,$local)
200                 echo >&2 "* $1: fast forward to $3"
201                 echo >&2 "  old..new: $oldshort_..$newshort_"
202                 git-update-ref -m "$GIT_REFLOG_ACTION: fast-forward" "$1" "$2" "$local"
203                 ;;
204             *)
205                 false
206                 ;;
207             esac || {
208                 case ",$force,$single_force," in
209                 *,t,*)
210                         echo >&2 "* $1: forcing update to non-fast forward $3"
211                         echo >&2 "  old...new: $oldshort_...$newshort_"
212                         git-update-ref -m "$GIT_REFLOG_ACTION: forced-update" "$1" "$2" "$local"
213                         ;;
214                 *)
215                         echo >&2 "* $1: not updating to non-fast forward $3"
216                         echo >&2 "  old...new: $oldshort_...$newshort_"
217                         exit 1
218                         ;;
219                 esac
220             }
221         else
222             echo >&2 "* $1: storing $3"
223             echo >&2 "  $label_: $newshort_"
224             git-update-ref -m "$GIT_REFLOG_ACTION: storing head" "$1" "$2"
225         fi
226         ;;
227     esac
228 }
229
230 # updating the current HEAD with git-fetch in a bare
231 # repository is always fine.
232 if test -z "$update_head_ok" && test $(is_bare_repository) = false
233 then
234         orig_head=$(git-rev-parse --verify HEAD 2>/dev/null)
235 fi
236
237 # If --tags (and later --heads or --all) is specified, then we are
238 # not talking about defaults stored in Pull: line of remotes or
239 # branches file, and just fetch those and refspecs explicitly given.
240 # Otherwise we do what we always did.
241
242 reflist=$(get_remote_refs_for_fetch "$@")
243 if test "$tags"
244 then
245         taglist=`IFS='  ' &&
246                   echo "$ls_remote_result" |
247                   while read sha1 name
248                   do
249                         case "$sha1" in
250                         fail)
251                                 exit 1
252                         esac
253                         case "$name" in
254                         *^*) continue ;;
255                         refs/tags/*) ;;
256                         *) continue ;;
257                         esac
258                         if git-check-ref-format "$name"
259                         then
260                             echo ".${name}:${name}"
261                         else
262                             echo >&2 "warning: tag ${name} ignored"
263                         fi
264                   done` || exit
265         if test "$#" -gt 1
266         then
267                 # remote URL plus explicit refspecs; we need to merge them.
268                 reflist="$reflist$LF$taglist"
269         else
270                 # No explicit refspecs; fetch tags only.
271                 reflist=$taglist
272         fi
273 fi
274
275 fetch_main () {
276   reflist="$1"
277   refs=
278   rref=
279
280   for ref in $reflist
281   do
282       refs="$refs$LF$ref"
283
284       # These are relative path from $GIT_DIR, typically starting at refs/
285       # but may be HEAD
286       if expr "z$ref" : 'z\.' >/dev/null
287       then
288           not_for_merge=t
289           ref=$(expr "z$ref" : 'z\.\(.*\)')
290       else
291           not_for_merge=
292       fi
293       if expr "z$ref" : 'z+' >/dev/null
294       then
295           single_force=t
296           ref=$(expr "z$ref" : 'z+\(.*\)')
297       else
298           single_force=
299       fi
300       remote_name=$(expr "z$ref" : 'z\([^:]*\):')
301       local_name=$(expr "z$ref" : 'z[^:]*:\(.*\)')
302
303       rref="$rref$LF$remote_name"
304
305       # There are transports that can fetch only one head at a time...
306       case "$remote" in
307       http://* | https://* | ftp://*)
308           test -n "$shallow_depth" &&
309                 die "shallow clone with http not supported"
310           proto=`expr "$remote" : '\([^:]*\):'`
311           if [ -n "$GIT_SSL_NO_VERIFY" ]; then
312               curl_extra_args="-k"
313           fi
314           if [ -n "$GIT_CURL_FTP_NO_EPSV" -o \
315                 "`git-repo-config --bool http.noEPSV`" = true ]; then
316               noepsv_opt="--disable-epsv"
317           fi
318
319           # Find $remote_name from ls-remote output.
320           head=$(
321                 IFS='   '
322                 echo "$ls_remote_result" |
323                 while read sha1 name
324                 do
325                         test "z$name" = "z$remote_name" || continue
326                         echo "$sha1"
327                         break
328                 done
329           )
330           expr "z$head" : "z$_x40\$" >/dev/null ||
331                 die "No such ref $remote_name at $remote"
332           echo >&2 "Fetching $remote_name from $remote using $proto"
333           git-http-fetch -v -a "$head" "$remote/" || exit
334           ;;
335       rsync://*)
336           test -n "$shallow_depth" &&
337                 die "shallow clone with rsync not supported"
338           TMP_HEAD="$GIT_DIR/TMP_HEAD"
339           rsync -L -q "$remote/$remote_name" "$TMP_HEAD" || exit 1
340           head=$(git-rev-parse --verify TMP_HEAD)
341           rm -f "$TMP_HEAD"
342           test "$rsync_slurped_objects" || {
343               rsync -av --ignore-existing --exclude info \
344                   "$remote/objects/" "$GIT_OBJECT_DIRECTORY/" || exit
345
346               # Look at objects/info/alternates for rsync -- http will
347               # support it natively and git native ones will do it on
348               # the remote end.  Not having that file is not a crime.
349               rsync -q "$remote/objects/info/alternates" \
350                   "$GIT_DIR/TMP_ALT" 2>/dev/null ||
351                   rm -f "$GIT_DIR/TMP_ALT"
352               if test -f "$GIT_DIR/TMP_ALT"
353               then
354                   resolve_alternates "$remote" <"$GIT_DIR/TMP_ALT" |
355                   while read alt
356                   do
357                       case "$alt" in 'bad alternate: '*) die "$alt";; esac
358                       echo >&2 "Getting alternate: $alt"
359                       rsync -av --ignore-existing --exclude info \
360                       "$alt" "$GIT_OBJECT_DIRECTORY/" || exit
361                   done
362                   rm -f "$GIT_DIR/TMP_ALT"
363               fi
364               rsync_slurped_objects=t
365           }
366           ;;
367       *)
368           # We will do git native transport with just one call later.
369           continue ;;
370       esac
371
372       append_fetch_head "$head" "$remote" \
373           "$remote_name" "$remote_nick" "$local_name" "$not_for_merge" || exit
374
375   done
376
377   case "$remote" in
378   http://* | https://* | ftp://* | rsync://* )
379       ;; # we are already done.
380   *)
381     ( : subshell because we muck with IFS
382       IFS="     $LF"
383       (
384           git-fetch-pack --thin $exec $keep $shallow_depth "$remote" $rref ||
385           echo failed "$remote"
386       ) |
387       (
388         trap '
389                 if test -n "$keepfile" && test -f "$keepfile"
390                 then
391                         rm -f "$keepfile"
392                 fi
393         ' 0
394
395         keepfile=
396         while read sha1 remote_name
397         do
398           case "$sha1" in
399           failed)
400                   echo >&2 "Fetch failure: $remote"
401                   exit 1 ;;
402           # special line coming from index-pack with the pack name
403           pack)
404                   continue ;;
405           keep)
406                   keepfile="$GIT_OBJECT_DIRECTORY/pack/pack-$remote_name.keep"
407                   continue ;;
408           esac
409           found=
410           single_force=
411           for ref in $refs
412           do
413               case "$ref" in
414               +$remote_name:*)
415                   single_force=t
416                   not_for_merge=
417                   found="$ref"
418                   break ;;
419               .+$remote_name:*)
420                   single_force=t
421                   not_for_merge=t
422                   found="$ref"
423                   break ;;
424               .$remote_name:*)
425                   not_for_merge=t
426                   found="$ref"
427                   break ;;
428               $remote_name:*)
429                   not_for_merge=
430                   found="$ref"
431                   break ;;
432               esac
433           done
434           local_name=$(expr "z$found" : 'z[^:]*:\(.*\)')
435           append_fetch_head "$sha1" "$remote" \
436                   "$remote_name" "$remote_nick" "$local_name" \
437                   "$not_for_merge" || exit
438         done
439       )
440     ) || exit ;;
441   esac
442
443 }
444
445 fetch_main "$reflist" || exit
446
447 # automated tag following
448 case "$no_tags$tags" in
449 '')
450         case "$reflist" in
451         *:refs/*)
452                 # effective only when we are following remote branch
453                 # using local tracking branch.
454                 taglist=$(IFS=' ' &&
455                 echo "$ls_remote_result" |
456                 git-show-ref --exclude-existing=refs/tags/ |
457                 while read sha1 name
458                 do
459                         git-cat-file -t "$sha1" >/dev/null 2>&1 || continue
460                         echo >&2 "Auto-following $name"
461                         echo ".${name}:${name}"
462                 done)
463         esac
464         case "$taglist" in
465         '') ;;
466         ?*)
467                 # do not deepen a shallow tree when following tags
468                 shallow_depth=
469                 fetch_main "$taglist" || exit ;;
470         esac
471 esac
472
473 # If the original head was empty (i.e. no "master" yet), or
474 # if we were told not to worry, we do not have to check.
475 case "$orig_head" in
476 '')
477         ;;
478 ?*)
479         curr_head=$(git-rev-parse --verify HEAD 2>/dev/null)
480         if test "$curr_head" != "$orig_head"
481         then
482             git-update-ref \
483                         -m "$GIT_REFLOG_ACTION: Undoing incorrectly fetched HEAD." \
484                         HEAD "$orig_head"
485                 die "Cannot fetch into the current branch."
486         fi
487         ;;
488 esac