[PATCH] Update git-clone documentation
[git.git] / git-fetch.sh
1 #!/bin/sh
2 #
3 . git-sh-setup || die "Not a git archive"
4 . git-parse-remote
5 _x40='[0-9a-f][0-9a-f][0-9a-f][0-9a-f][0-9a-f]'
6 _x40="$_x40$_x40$_x40$_x40$_x40$_x40$_x40$_x40"
7
8 tags=
9 append=
10 force=
11 update_head_ok=
12 while case "$#" in 0) break ;; esac
13 do
14         case "$1" in
15         -a|--a|--ap|--app|--appe|--appen|--append)
16                 append=t
17                 ;;
18         -f|--f|--fo|--for|--forc|--force)
19                 force=t
20                 ;;
21         -t|--t|--ta|--tag|--tags)
22                 tags=t
23                 ;;
24         -u|--u|--up|--upd|--upda|--updat|--update|--update-|--update-h|\
25         --update-he|--update-hea|--update-head|--update-head-|\
26         --update-head-o|--update-head-ok)
27                 update_head_ok=t
28                 ;;
29         *)
30                 break
31                 ;;
32         esac
33         shift
34 done
35
36 case "$#" in
37 0)
38         test -f "$GIT_DIR/branches/origin" ||
39                 test -f "$GIT_DIR/remotes/origin" ||
40                         die "Where do you want to fetch from today?"
41         set origin ;;
42 esac
43
44 remote_nick="$1"
45 remote=$(get_remote_url "$@")
46 refs=
47 rref=
48 rsync_slurped_objects=
49
50 if test "" = "$append"
51 then
52         : >$GIT_DIR/FETCH_HEAD
53 fi
54
55 append_fetch_head () {
56     head_="$1"
57     remote_="$2"
58     remote_name_="$3"
59     remote_nick_="$4"
60     local_name_="$5"
61     case "$6" in
62     t) not_for_merge_='not-for-merge' ;;
63     '') not_for_merge_= ;;
64     esac
65
66     # remote-nick is the URL given on the command line (or a shorthand)
67     # remote-name is the $GIT_DIR relative refs/ path we computed
68     # for this refspec.
69     case "$remote_name_" in
70     HEAD)
71         note_= ;;
72     refs/heads/*)
73         note_="$(expr "$remote_name_" : 'refs/heads/\(.*\)')"
74         note_="branch '$note_' of " ;;
75     refs/tags/*)
76         note_="$(expr "$remote_name_" : 'refs/tags/\(.*\)')"
77         note_="tag '$note_' of " ;;
78     *)
79         note_="$remote_name of " ;;
80     esac
81     remote_1_=$(expr "$remote_" : '\(.*\)\.git/*$') &&
82         remote_="$remote_1_"
83     note_="$note_$remote_"
84
85     # 2.6.11-tree tag would not be happy to be fed to resolve.
86     if git-cat-file commit "$head_" >/dev/null 2>&1
87     then
88         headc_=$(git-rev-parse --verify "$head_^0") || exit
89         echo "$headc_   $not_for_merge_ $note_" >>$GIT_DIR/FETCH_HEAD
90         echo >&2 "* committish: $head_"
91         echo >&2 "  $note_"
92     else
93         echo "$head_    not-for-merge   $note_" >>$GIT_DIR/FETCH_HEAD
94         echo >&2 "* non-commit: $head_"
95         echo >&2 "  $note_"
96     fi
97     if test "$local_name_" != ""
98     then
99         # We are storing the head locally.  Make sure that it is
100         # a fast forward (aka "reverse push").
101         fast_forward_local "$local_name_" "$head_" "$note_"
102     fi
103 }
104
105 fast_forward_local () {
106     mkdir -p "$(dirname "$GIT_DIR/$1")"
107     case "$1" in
108     refs/tags/*)
109         # Tags need not be pointing at commits so there
110         # is no way to guarantee "fast-forward" anyway.
111         if test -f "$GIT_DIR/$1"
112         then
113                 echo >&2 "* $1: updating with $3"
114         else
115                 echo >&2 "* $1: storing $3"
116         fi
117         git-update-ref "$1" "$2" 
118         ;;
119
120     refs/heads/*)
121         # $1 is the ref being updated.
122         # $2 is the new value for the ref.
123         local=$(git-rev-parse --verify "$1^0" 2>/dev/null)
124         if test "$local"
125         then
126             # Require fast-forward.
127             mb=$(git-merge-base "$local" "$2") &&
128             case "$2,$mb" in
129             $local,*)
130                 echo >&2 "* $1: same as $3"
131                 ;;
132             *,$local)
133                 echo >&2 "* $1: fast forward to $3"
134                 git-update-ref "$1" "$2" "$local"
135                 ;;
136             *)
137                 false
138                 ;;
139             esac || {
140                 echo >&2 "* $1: does not fast forward to $3;"
141                 case ",$force,$single_force," in
142                 *,t,*)
143                         echo >&2 "  forcing update."
144                         git-update-ref "$1" "$2" "$local"
145                         ;;
146                 *)
147                         echo >&2 "  not updating."
148                         ;;
149                 esac
150             }
151         else
152             echo >&2 "* $1: storing $3"
153             git-update-ref "$1" "$2"
154         fi
155         ;;
156     esac
157 }
158
159 case "$update_head_ok" in
160 '')
161         orig_head=$(git-rev-parse --verify HEAD 2>/dev/null)
162         ;;
163 esac
164
165 # If --tags (and later --heads or --all) is specified, then we are
166 # not talking about defaults stored in Pull: line of remotes or
167 # branches file, and just fetch those and refspecs explicitly given.
168 # Otherwise we do what we always did.
169
170 reflist=$(get_remote_refs_for_fetch "$@")
171 if test "$tags"
172 then
173         taglist=$(git-ls-remote --tags "$remote" | awk '{ print "."$2":"$2 }')
174         if test "$#" -gt 1
175         then
176                 # remote URL plus explicit refspecs; we need to merge them.
177                 reflist="$reflist $taglist"
178         else
179                 # No explicit refspecs; fetch tags only.
180                 reflist=$taglist
181         fi
182 fi
183
184 for ref in $reflist
185 do
186     refs="$refs $ref"
187
188     # These are relative path from $GIT_DIR, typically starting at refs/
189     # but may be HEAD
190     if expr "$ref" : '\.' >/dev/null
191     then
192         not_for_merge=t
193         ref=$(expr "$ref" : '\.\(.*\)')
194     else
195         not_for_merge=
196     fi
197     if expr "$ref" : '\+' >/dev/null
198     then
199         single_force=t
200         ref=$(expr "$ref" : '\+\(.*\)')
201     else
202         single_force=
203     fi
204     remote_name=$(expr "$ref" : '\([^:]*\):')
205     local_name=$(expr "$ref" : '[^:]*:\(.*\)')
206
207     rref="$rref $remote_name"
208
209     # There are transports that can fetch only one head at a time...
210     case "$remote" in
211     http://* | https://*)
212         if [ -n "$GIT_SSL_NO_VERIFY" ]; then
213             curl_extra_args="-k"
214         fi
215         head=$(curl -nsf $curl_extra_args "$remote/$remote_name") &&
216         expr "$head" : "$_x40\$" >/dev/null ||
217                 die "Failed to fetch $remote_name from $remote"
218         echo >&2 Fetching "$remote_name from $remote" using http
219         git-http-fetch -v -a "$head" "$remote/" || exit
220         ;;
221     rsync://*)
222         TMP_HEAD="$GIT_DIR/TMP_HEAD"
223         rsync -L -q "$remote/$remote_name" "$TMP_HEAD" || exit 1
224         head=$(git-rev-parse --verify TMP_HEAD)
225         rm -f "$TMP_HEAD"
226         test "$rsync_slurped_objects" || {
227             rsync -av --ignore-existing --exclude info \
228                 "$remote/objects/" "$GIT_OBJECT_DIRECTORY/" || exit
229
230             # Look at objects/info/alternates for rsync -- http will
231             # support it natively and git native ones will do it on the remote
232             # end.  Not having that file is not a crime.
233             rsync -q "$remote/objects/info/alternates" \
234                 "$GIT_DIR/TMP_ALT" 2>/dev/null ||
235                 rm -f "$GIT_DIR/TMP_ALT"
236             if test -f "$GIT_DIR/TMP_ALT"
237             then
238                 resolve_alternates "$remote" <"$GIT_DIR/TMP_ALT" |
239                 while read alt
240                 do
241                     case "$alt" in 'bad alternate: '*) die "$alt";; esac
242                     echo >&2 "Getting alternate: $alt"
243                     rsync -av --ignore-existing --exclude info \
244                     "$alt" "$GIT_OBJECT_DIRECTORY/" || exit
245                 done
246                 rm -f "$GIT_DIR/TMP_ALT"
247             fi
248             rsync_slurped_objects=t
249         }
250         ;;
251     *)
252         # We will do git native transport with just one call later.
253         continue ;;
254     esac
255
256     append_fetch_head "$head" "$remote" \
257         "$remote_name" "$remote_nick" "$local_name" "$not_for_merge"
258
259 done
260
261 case "$remote" in
262 http://* | https://* | rsync://* )
263     ;; # we are already done.
264 *)
265     (
266         git-fetch-pack "$remote" $rref || echo failed "$remote"
267     ) |
268     while read sha1 remote_name
269     do
270         case "$sha1" in
271         failed)
272                 echo >&2 "Fetch failure: $remote"
273                 exit 1 ;;
274         esac
275         found=
276         single_force=
277         for ref in $refs
278         do
279             case "$ref" in
280             +$remote_name:*)
281                 single_force=t
282                 not_for_merge=
283                 found="$ref"
284                 break ;;
285             .+$remote_name:*)
286                 single_force=t
287                 not_for_merge=t
288                 found="$ref"
289                 break ;;
290             .$remote_name:*)
291                 not_for_merge=t
292                 found="$ref"
293                 break ;;
294             $remote_name:*)
295                 not_for_merge=
296                 found="$ref"
297                 break ;;
298             esac
299         done
300         local_name=$(expr "$found" : '[^:]*:\(.*\)')
301         append_fetch_head "$sha1" "$remote" \
302                 "$remote_name" "$remote_nick" "$local_name" "$not_for_merge"
303     done || exit
304     ;;
305 esac
306
307 # If the original head was empty (i.e. no "master" yet), or
308 # if we were told not to worry, we do not have to check.
309 case ",$update_head_ok,$orig_head," in
310 *,, | t,* )
311         ;;
312 *)
313         curr_head=$(git-rev-parse --verify HEAD 2>/dev/null)
314         if test "$curr_head" != "$orig_head"
315         then
316                 git-update-ref HEAD "$orig_head"
317                 die "Cannot fetch into the current branch."
318         fi
319         ;;
320 esac