strbuf_read(): skip unnecessary strbuf_grow() at eof
[git] / git-pull.sh
1 #!/bin/sh
2 #
3 # Copyright (c) 2005 Junio C Hamano
4 #
5 # Fetch one or more remote refs and merge it/them into the current HEAD.
6
7 USAGE='[-n | --no-stat] [--[no-]commit] [--[no-]squash] [--[no-]ff|--ff-only] [--[no-]rebase|--rebase=preserve] [-s strategy]... [<fetch-options>] <repo> <head>...'
8 LONG_USAGE='Fetch one or more remote refs and integrate it/them with the current HEAD.'
9 SUBDIRECTORY_OK=Yes
10 OPTIONS_SPEC=
11 . git-sh-setup
12 . git-sh-i18n
13 set_reflog_action "pull${1+ $*}"
14 require_work_tree_exists
15 cd_to_toplevel
16
17
18 die_conflict () {
19     git diff-index --cached --name-status -r --ignore-submodules HEAD --
20     if [ $(git config --bool --get advice.resolveConflict || echo true) = "true" ]; then
21         die "$(gettext "Pull is not possible because you have unmerged files.
22 Please, fix them up in the work tree, and then use 'git add/rm <file>'
23 as appropriate to mark resolution, or use 'git commit -a'.")"
24     else
25         die "$(gettext "Pull is not possible because you have unmerged files.")"
26     fi
27 }
28
29 die_merge () {
30     if [ $(git config --bool --get advice.resolveConflict || echo true) = "true" ]; then
31         die "$(gettext "You have not concluded your merge (MERGE_HEAD exists).
32 Please, commit your changes before you can merge.")"
33     else
34         die "$(gettext "You have not concluded your merge (MERGE_HEAD exists).")"
35     fi
36 }
37
38 test -z "$(git ls-files -u)" || die_conflict
39 test -f "$GIT_DIR/MERGE_HEAD" && die_merge
40
41 bool_or_string_config () {
42         git config --bool "$1" 2>/dev/null || git config "$1"
43 }
44
45 strategy_args= diffstat= no_commit= squash= no_ff= ff_only=
46 log_arg= verbosity= progress= recurse_submodules= verify_signatures=
47 merge_args= edit= rebase_args=
48 curr_branch=$(git symbolic-ref -q HEAD)
49 curr_branch_short="${curr_branch#refs/heads/}"
50 rebase=$(bool_or_string_config branch.$curr_branch_short.rebase)
51 if test -z "$rebase"
52 then
53         rebase=$(bool_or_string_config pull.rebase)
54 fi
55
56 # Setup default fast-forward options via `pull.ff`
57 pull_ff=$(git config pull.ff)
58 case "$pull_ff" in
59 false)
60         no_ff=--no-ff
61         ;;
62 only)
63         ff_only=--ff-only
64         ;;
65 esac
66
67
68 dry_run=
69 while :
70 do
71         case "$1" in
72         -q|--quiet)
73                 verbosity="$verbosity -q" ;;
74         -v|--verbose)
75                 verbosity="$verbosity -v" ;;
76         --progress)
77                 progress=--progress ;;
78         --no-progress)
79                 progress=--no-progress ;;
80         -n|--no-stat|--no-summary)
81                 diffstat=--no-stat ;;
82         --stat|--summary)
83                 diffstat=--stat ;;
84         --log|--no-log)
85                 log_arg=$1 ;;
86         --no-c|--no-co|--no-com|--no-comm|--no-commi|--no-commit)
87                 no_commit=--no-commit ;;
88         --c|--co|--com|--comm|--commi|--commit)
89                 no_commit=--commit ;;
90         -e|--edit)
91                 edit=--edit ;;
92         --no-edit)
93                 edit=--no-edit ;;
94         --sq|--squ|--squa|--squas|--squash)
95                 squash=--squash ;;
96         --no-sq|--no-squ|--no-squa|--no-squas|--no-squash)
97                 squash=--no-squash ;;
98         --ff)
99                 no_ff=--ff ;;
100         --no-ff)
101                 no_ff=--no-ff ;;
102         --ff-only)
103                 ff_only=--ff-only ;;
104         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
105                 --strateg=*|--strategy=*|\
106         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
107                 case "$#,$1" in
108                 *,*=*)
109                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
110                 1,*)
111                         usage ;;
112                 *)
113                         strategy="$2"
114                         shift ;;
115                 esac
116                 strategy_args="${strategy_args}-s $strategy "
117                 ;;
118         -X*)
119                 case "$#,$1" in
120                 1,-X)
121                         usage ;;
122                 *,-X)
123                         xx="-X $(git rev-parse --sq-quote "$2")"
124                         shift ;;
125                 *,*)
126                         xx=$(git rev-parse --sq-quote "$1") ;;
127                 esac
128                 merge_args="$merge_args$xx "
129                 ;;
130         -r=*|--r=*|--re=*|--reb=*|--reba=*|--rebas=*|--rebase=*)
131                 rebase="${1#*=}"
132                 ;;
133         -r|--r|--re|--reb|--reba|--rebas|--rebase)
134                 rebase=true
135                 ;;
136         --no-r|--no-re|--no-reb|--no-reba|--no-rebas|--no-rebase)
137                 rebase=false
138                 ;;
139         --recurse-submodules)
140                 recurse_submodules=--recurse-submodules
141                 ;;
142         --recurse-submodules=*)
143                 recurse_submodules="$1"
144                 ;;
145         --no-recurse-submodules)
146                 recurse_submodules=--no-recurse-submodules
147                 ;;
148         --verify-signatures)
149                 verify_signatures=--verify-signatures
150                 ;;
151         --no-verify-signatures)
152                 verify_signatures=--no-verify-signatures
153                 ;;
154         --gpg-sign|-S)
155                 gpg_sign_args=-S
156                 ;;
157         --gpg-sign=*)
158                 gpg_sign_args=$(git rev-parse --sq-quote "-S${1#--gpg-sign=}")
159                 ;;
160         -S*)
161                 gpg_sign_args=$(git rev-parse --sq-quote "$1")
162                 ;;
163         --d|--dr|--dry|--dry-|--dry-r|--dry-ru|--dry-run)
164                 dry_run=--dry-run
165                 ;;
166         -h|--help-all)
167                 usage
168                 ;;
169         *)
170                 # Pass thru anything that may be meant for fetch.
171                 break
172                 ;;
173         esac
174         shift
175 done
176
177 case "$rebase" in
178 preserve)
179         rebase=true
180         rebase_args=--preserve-merges
181         ;;
182 true|false|'')
183         ;;
184 *)
185         echo "Invalid value for --rebase, should be true, false, or preserve"
186         usage
187         exit 1
188         ;;
189 esac
190
191 error_on_no_merge_candidates () {
192         exec >&2
193         for opt
194         do
195                 case "$opt" in
196                 -t|--t|--ta|--tag|--tags)
197                         echo "It doesn't make sense to pull all tags; you probably meant:"
198                         echo "  git fetch --tags"
199                         exit 1
200                 esac
201         done
202
203         if test true = "$rebase"
204         then
205                 op_type=rebase
206                 op_prep=against
207         else
208                 op_type=merge
209                 op_prep=with
210         fi
211
212         upstream=$(git config "branch.$curr_branch_short.merge")
213         remote=$(git config "branch.$curr_branch_short.remote")
214
215         if [ $# -gt 1 ]; then
216                 if [ "$rebase" = true ]; then
217                         printf "There is no candidate for rebasing against "
218                 else
219                         printf "There are no candidates for merging "
220                 fi
221                 echo "among the refs that you just fetched."
222                 echo "Generally this means that you provided a wildcard refspec which had no"
223                 echo "matches on the remote end."
224         elif [ $# -gt 0 ] && [ "$1" != "$remote" ]; then
225                 echo "You asked to pull from the remote '$1', but did not specify"
226                 echo "a branch. Because this is not the default configured remote"
227                 echo "for your current branch, you must specify a branch on the command line."
228         elif [ -z "$curr_branch" -o -z "$upstream" ]; then
229                 . git-parse-remote
230                 error_on_missing_default_upstream "pull" $op_type $op_prep \
231                         "git pull <remote> <branch>"
232         else
233                 echo "Your configuration specifies to $op_type $op_prep the ref '${upstream#refs/heads/}'"
234                 echo "from the remote, but no such ref was fetched."
235         fi
236         exit 1
237 }
238
239 test true = "$rebase" && {
240         if ! git rev-parse -q --verify HEAD >/dev/null
241         then
242                 # On an unborn branch
243                 if test -f "$GIT_DIR/index"
244                 then
245                         die "$(gettext "updating an unborn branch with changes added to the index")"
246                 fi
247         else
248                 require_clean_work_tree "pull with rebase" "Please commit or stash them."
249         fi
250         oldremoteref= &&
251         test -n "$curr_branch" &&
252         . git-parse-remote &&
253         remoteref="$(get_remote_merge_branch "$@" 2>/dev/null)" &&
254         oldremoteref=$(git merge-base --fork-point "$remoteref" $curr_branch 2>/dev/null)
255 }
256 orig_head=$(git rev-parse -q --verify HEAD)
257 git fetch $verbosity $progress $dry_run $recurse_submodules --update-head-ok "$@" || exit 1
258 test -z "$dry_run" || exit 0
259
260 curr_head=$(git rev-parse -q --verify HEAD)
261 if test -n "$orig_head" && test "$curr_head" != "$orig_head"
262 then
263         # The fetch involved updating the current branch.
264
265         # The working tree and the index file is still based on the
266         # $orig_head commit, but we are merging into $curr_head.
267         # First update the working tree to match $curr_head.
268
269         eval_gettextln "Warning: fetch updated the current branch head.
270 Warning: fast-forwarding your working tree from
271 Warning: commit \$orig_head." >&2
272         git update-index -q --refresh
273         git read-tree -u -m "$orig_head" "$curr_head" ||
274                 die "$(eval_gettext "Cannot fast-forward your working tree.
275 After making sure that you saved anything precious from
276 $ git diff \$orig_head
277 output, run
278 $ git reset --hard
279 to recover.")"
280
281 fi
282
283 merge_head=$(sed -e '/  not-for-merge   /d' \
284         -e 's/  .*//' "$GIT_DIR"/FETCH_HEAD | \
285         tr '\012' ' ')
286
287 case "$merge_head" in
288 '')
289         error_on_no_merge_candidates "$@"
290         ;;
291 ?*' '?*)
292         if test -z "$orig_head"
293         then
294                 die "$(gettext "Cannot merge multiple branches into empty head")"
295         fi
296         if test true = "$rebase"
297         then
298                 die "$(gettext "Cannot rebase onto multiple branches")"
299         fi
300         ;;
301 esac
302
303 # Pulling into unborn branch: a shorthand for branching off
304 # FETCH_HEAD, for lazy typers.
305 if test -z "$orig_head"
306 then
307         # Two-way merge: we claim the index is based on an empty tree,
308         # and try to fast-forward to HEAD.  This ensures we will not
309         # lose index/worktree changes that the user already made on
310         # the unborn branch.
311         empty_tree=4b825dc642cb6eb9a060e54bf8d69288fbee4904
312         git read-tree -m -u $empty_tree $merge_head &&
313         git update-ref -m "initial pull" HEAD $merge_head "$curr_head"
314         exit
315 fi
316
317 if test true = "$rebase"
318 then
319         o=$(git show-branch --merge-base $curr_branch $merge_head $oldremoteref)
320         if test "$oldremoteref" = "$o"
321         then
322                 unset oldremoteref
323         fi
324 fi
325
326 merge_name=$(git fmt-merge-msg $log_arg <"$GIT_DIR/FETCH_HEAD") || exit
327 case "$rebase" in
328 true)
329         eval="git-rebase $diffstat $strategy_args $merge_args $rebase_args $verbosity"
330         eval="$eval $gpg_sign_args"
331         eval="$eval --onto $merge_head ${oldremoteref:-$merge_head}"
332         ;;
333 *)
334         eval="git-merge $diffstat $no_commit $verify_signatures $edit $squash $no_ff $ff_only"
335         eval="$eval $log_arg $strategy_args $merge_args $verbosity $progress"
336         eval="$eval $gpg_sign_args"
337         eval="$eval \"\$merge_name\" HEAD $merge_head"
338         ;;
339 esac
340 eval "exec $eval"