1#!/bin/sh 2# 3# Copyright (c) 2005 Junio C Hamano 4# 5 6USAGE='[-n] [--summary] [--[no-]commit] [--[no-]squash] [--[no-]ff] [-s <strategy>] [-m=<merge-message>] <commit>+' 7 8SUBDIRECTORY_OK=Yes 9. git-sh-setup 10require_work_tree 11cd_to_toplevel 12 13test -z"$(git ls-files -u)"|| 14 die "You are in the middle of a conflicted merge." 15 16LF=' 17' 18 19all_strategies='recur recursive octopus resolve stupid ours subtree' 20default_twohead_strategies='recursive' 21default_octopus_strategies='octopus' 22no_fast_forward_strategies='subtree ours' 23no_trivial_strategies='recursive recur subtree ours' 24use_strategies= 25 26allow_fast_forward=t 27allow_trivial_merge=t 28 29dropsave() { 30rm-f --"$GIT_DIR/MERGE_HEAD""$GIT_DIR/MERGE_MSG" \ 31"$GIT_DIR/MERGE_STASH"||exit1 32} 33 34savestate() { 35# Stash away any local modifications. 36 git stash create >"$GIT_DIR/MERGE_STASH" 37} 38 39restorestate() { 40iftest -f"$GIT_DIR/MERGE_STASH" 41then 42 git reset--hard$head>/dev/null 43 git stash apply $(cat "$GIT_DIR/MERGE_STASH") 44 git update-index --refresh>/dev/null 45fi 46} 47 48finish_up_to_date () { 49case"$squash"in 50 t) 51echo"$1(nothing to squash)";; 52'') 53echo"$1";; 54esac 55 dropsave 56} 57 58squash_message () { 59echo Squashed commit of the following: 60echo 61 git log --no-merges ^"$head"$remoteheads 62} 63 64finish () { 65iftest''="$2" 66then 67 rlogm="$GIT_REFLOG_ACTION" 68else 69echo"$2" 70 rlogm="$GIT_REFLOG_ACTION:$2" 71fi 72case"$squash"in 73 t) 74echo"Squash commit -- not updating HEAD" 75 squash_message >"$GIT_DIR/SQUASH_MSG" 76;; 77'') 78case"$merge_msg"in 79'') 80echo"No merge message -- not updating HEAD" 81;; 82*) 83 git update-ref -m"$rlogm" HEAD "$1""$head"||exit1 84 git gc --auto 85;; 86esac 87;; 88esac 89case"$1"in 90'') 91;; 92 ?*) 93iftest"$show_diffstat"= t 94then 95# We want color (if set), but no pager 96 GIT_PAGER='' git diff--stat --summary -M"$head""$1" 97fi 98;; 99esac 100 101# Run a post-merge hook 102iftest -x"$GIT_DIR"/hooks/post-merge 103then 104case"$squash"in 105 t) 106"$GIT_DIR"/hooks/post-merge1 107;; 108'') 109"$GIT_DIR"/hooks/post-merge0 110;; 111esac 112fi 113} 114 115merge_name () { 116 remote="$1" 117 rh=$(git rev-parse --verify "$remote^0" 2>/dev/null)||return 118 bh=$(git show-ref -s --verify "refs/heads/$remote" 2>/dev/null) 119iftest"$rh"="$bh" 120then 121echo"$rhbranch '$remote' of ." 122elif truname=$(expr "$remote" : '\(.*\)~[1-9][0-9]*$') && 123 git show-ref -q --verify "refs/heads/$truname" 2>/dev/null 124 then 125 echo "$rhbranch '$truname' (early part) of ." 126 elif test "$remote" = "FETCH_HEAD" -a -r "$GIT_DIR/FETCH_HEAD" 127 then 128 sed -e 's/ not-for-merge/ /' -e 1q \ 129 "$GIT_DIR/FETCH_HEAD" 130 else 131 echo "$rhcommit '$remote'" 132 fi 133} 134 135parse_option () { 136 case "$1" in 137 -n|--n|--no|--no-|--no-s|--no-su|--no-sum|--no-summ|\ 138 --no-summa|--no-summar|--no-summary) 139 show_diffstat=false ;; 140 --summary) 141 show_diffstat=t ;; 142 --sq|--squ|--squa|--squas|--squash) 143 allow_fast_forward=t squash=t no_commit=t ;; 144 --no-sq|--no-squ|--no-squa|--no-squas|--no-squash) 145 allow_fast_forward=t squash= no_commit= ;; 146 --c|--co|--com|--comm|--commi|--commit) 147 allow_fast_forward=t squash= no_commit= ;; 148 --no-c|--no-co|--no-com|--no-comm|--no-commi|--no-commit) 149 allow_fast_forward=t squash= no_commit=t ;; 150 --ff) 151 allow_fast_forward=t squash= no_commit= ;; 152 --no-ff) 153 allow_fast_forward=false squash= no_commit= ;; 154 -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\ 155 --strateg=*|--strategy=*|\ 156 -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy) 157 case "$#,$1" in 158 *,*=*) 159 strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;; 160 1,*) 161 usage ;; 162 *) 163 strategy="$2" 164 shift ;; 165 esac 166 case "$all_strategies" in 167 *"$strategy"*) 168 use_strategies="$use_strategies$strategy" ;; 169 *) 170 die "available strategies are:$all_strategies" ;; 171 esac 172 ;; 173 -m=*|--m=*|--me=*|--mes=*|--mess=*|--messa=*|--messag=*|--message=*) 174 merge_msg=`expr "z$1" : 'z-[^=]*=\(.*\)'` 175 have_message=t 176 ;; 177 -m|--m|--me|--mes|--mess|--messa|--messag|--message) 178 shift 179 case "$#" in 180 1) usage ;; 181 esac 182 merge_msg="$1" 183 have_message=t 184 ;; 185 -*) usage ;; 186 *) return 1 ;; 187 esac 188 shift 189 args_left=$# 190} 191 192parse_config () { 193 while test$#-gt 0 194 do 195 parse_option "$@" || usage 196 while test$args_left-lt$# 197 do 198 shift 199 done 200 done 201} 202 203test$#!= 0 || usage 204 205have_message= 206 207if branch=$(git-symbolic-ref -q HEAD) 208then 209 mergeopts=$(git config "branch.${branch#refs/heads/}.mergeoptions") 210 if test -n "$mergeopts" 211 then 212 parse_config$mergeopts 213 fi 214fi 215 216while parse_option "$@" 217do 218 while test$args_left-lt$# 219 do 220 shift 221 done 222done 223 224if test -z "$show_diffstat"; then 225 test "$(git config --bool merge.diffstat)" = false && show_diffstat=false 226 test -z "$show_diffstat" && show_diffstat=t 227fi 228 229# This could be traditional "merge <msg> HEAD <commit>..." and the 230# way we can tell it is to see if the second token is HEAD, but some 231# people might have misused the interface and used a committish that 232# is the same as HEAD there instead. Traditional format never would 233# have "-m" so it is an additional safety measure to check for it. 234 235if test -z "$have_message" && 236 second_token=$(git rev-parse --verify "$2^0" 2>/dev/null)&& 237 head_commit=$(git rev-parse --verify "HEAD" 2>/dev/null)&& 238 test "$second_token" = "$head_commit" 239then 240 merge_msg="$1" 241 shift 242 head_arg="$1" 243 shift 244elif ! git rev-parse --verify HEAD >/dev/null 2>&1 245then 246 # If the merged head is a valid one there is no reason to 247 # forbid "git merge" into a branch yet to be born. We do 248 # the same for "git pull". 249 if test 1 -ne$# 250 then 251 echo >&2 "Can merge only exactly one commit into empty head" 252 exit 1 253 fi 254 255 rh=$(git rev-parse --verify "$1^0")|| 256 die "$1- not something we can merge" 257 258 git update-ref -m "initial pull" HEAD "$rh" "" && 259 git read-tree --reset -u HEAD 260 exit 261 262else 263 # We are invoked directly as the first-class UI. 264 head_arg=HEAD 265 266 # All the rest are the commits being merged; prepare 267 # the standard merge summary message to be appended to 268 # the given message. If remote is invalid we will die 269 # later in the common codepath so we discard the error 270 # in this loop. 271 merge_name=$(for remote 272 do 273 merge_name "$remote" 274 done | git fmt-merge-msg 275 ) 276 merge_msg="${merge_msg:+$merge_msg$LF$LF}$merge_name" 277fi 278head=$(git rev-parse --verify "$head_arg"^0)|| usage 279 280# All the rest are remote heads 281test "$#" = 0 && usage ;# we need at least one remote head. 282set_reflog_action "merge $*" 283 284remoteheads= 285for remote 286do 287 remotehead=$(git rev-parse --verify "$remote"^0 2>/dev/null)|| 288 die "$remote- not something we can merge" 289 remoteheads="${remoteheads}$remotehead" 290 eval GITHEAD_$remotehead='"$remote"' 291 export GITHEAD_$remotehead 292done 293set x$remoteheads; shift 294 295case "$use_strategies" in 296'') 297 case "$#" in 298 1) 299 var="`git config --get pull.twohead`" 300 if test -n "$var" 301 then 302 use_strategies="$var" 303 else 304 use_strategies="$default_twohead_strategies" 305 fi ;; 306 *) 307 var="`git config --get pull.octopus`" 308 if test -n "$var" 309 then 310 use_strategies="$var" 311 else 312 use_strategies="$default_octopus_strategies" 313 fi ;; 314 esac 315 ;; 316esac 317 318for s in$use_strategies 319do 320 for ss in$no_fast_forward_strategies 321 do 322 case "$s" in 323 *"$ss"*) 324 allow_fast_forward=f 325 break 326 ;; 327 esac 328 done 329 for ss in$no_trivial_strategies 330 do 331 case "$s" in 332 *"$ss"*) 333 allow_trivial_merge=f 334 break 335 ;; 336 esac 337 done 338done 339 340case "$#" in 3411) 342 common=$(git merge-base --all $head "$@") 343 ;; 344*) 345 common=$(git show-branch --merge-base $head "$@") 346 ;; 347esac 348echo "$head" >"$GIT_DIR/ORIG_HEAD" 349 350case "$allow_fast_forward,$#,$common,$no_commit" in 351?,*,'',*) 352 # No common ancestors found. We need a real merge. 353 ;; 354?,1,"$1",*) 355 # If head can reach all the merge then we are up to date. 356 # but first the most common case of merging one remote. 357 finish_up_to_date "Already up-to-date." 358 exit 0 359 ;; 360t,1,"$head",*) 361 # Again the most common case of merging one remote. 362 echo "Updating$(git rev-parse --short $head)..$(git rev-parse --short $1)" 363 git update-index --refresh 2>/dev/null 364 msg="Fast forward" 365 if test -n "$have_message" 366 then 367 msg="$msg(no commit created; -m option ignored)" 368 fi 369 new_head=$(git rev-parse --verify "$1^0")&& 370 git read-tree -v -m -u --exclude-per-directory=.gitignore$head"$new_head" && 371 finish "$new_head" "$msg" || exit 372 dropsave 373 exit 0 374 ;; 375?,1,?*"$LF"?*,*) 376 # We are not doing octopus and not fast forward. Need a 377 # real merge. 378 ;; 379?,1,*,) 380 # We are not doing octopus, not fast forward, and have only 381 # one common. 382 git update-index --refresh 2>/dev/null 383 case "$allow_trivial_merge" in 384 t) 385 # See if it is really trivial. 386 git var GIT_COMMITTER_IDENT >/dev/null || exit 387 echo "Trying really trivial in-index merge..." 388 if git read-tree --trivial -m -u -v$common$head"$1" && 389 result_tree=$(git write-tree) 390 then 391 echo "Wonderful." 392 result_commit=$( 393 printf '%s\n' "$merge_msg" | 394 git commit-tree$result_tree-p HEAD -p "$1" 395 ) || exit 396 finish "$result_commit" "In-index merge" 397 dropsave 398 exit 0 399 fi 400 echo "Nope." 401 esac 402 ;; 403*) 404 # An octopus. If we can reach all the remote we are up to date. 405 up_to_date=t 406 for remote 407 do 408 common_one=$(git merge-base --all $head $remote) 409 if test "$common_one" != "$remote" 410 then 411 up_to_date=f 412 break 413 fi 414 done 415 if test "$up_to_date" = t 416 then 417 finish_up_to_date "Already up-to-date. Yeeah!" 418 exit 0 419 fi 420 ;; 421esac 422 423# We are going to make a new commit. 424git var GIT_COMMITTER_IDENT >/dev/null || exit 425 426# At this point, we need a real merge. No matter what strategy 427# we use, it would operate on the index, possibly affecting the 428# working tree, and when resolved cleanly, have the desired tree 429# in the index -- this means that the index must be in sync with 430# the$headcommit. The strategies are responsible to ensure this. 431 432case "$use_strategies" in 433?*''?*) 434 # Stash away the local changes so that we can try more than one. 435 savestate 436 single_strategy=no 437 ;; 438*) 439 rm -f "$GIT_DIR/MERGE_STASH" 440 single_strategy=yes 441 ;; 442esac 443 444result_tree= best_cnt=-1 best_strategy= wt_strategy= 445merge_was_ok= 446for strategy in$use_strategies 447do 448 test "$wt_strategy" = '' || { 449 echo "Rewinding the tree to pristine..." 450 restorestate 451 } 452 case "$single_strategy" in 453 no) 454 echo "Trying merge strategy$strategy..." 455 ;; 456 esac 457 458 # Remember which strategy left the state in the working tree 459 wt_strategy=$strategy 460 461 git-merge-$strategy$common-- "$head_arg" "$@" 462 exit=$? 463 if test "$no_commit" = t && test "$exit" = 0 464 then 465 merge_was_ok=t 466 exit=1 ;# pretend it left conflicts. 467 fi 468 469 test "$exit" = 0 || { 470 471 # The backend exits with 1 when conflicts are left to be resolved, 472 # with 2 when it does not handle the given merge at all. 473 474 if test "$exit" -eq 1 475 then 476 cnt=`{ 477 git diff-files --name-only 478 git ls-files --unmerged 479 } | wc -l` 480 if test$best_cnt-le 0 -o$cnt-le$best_cnt 481 then 482 best_strategy=$strategy 483 best_cnt=$cnt 484 fi 485 fi 486 continue 487 } 488 489 # Automerge succeeded. 490 result_tree=$(git write-tree)&& break 491done 492 493# If we have a resulting tree, that means the strategy module 494# auto resolved the merge cleanly. 495if test '' != "$result_tree" 496then 497 if test "$allow_fast_forward" = "t" 498 then 499 parents=$(git show-branch --independent "$head" "$@") 500 else 501 parents=$(git rev-parse "$head" "$@") 502 fi 503 parents=$(echo "$parents" | sed -e 's/^/-p /') 504 result_commit=$(printf '%s\n' "$merge_msg" | git commit-tree $result_tree $parents)|| exit 505 finish "$result_commit" "Merge made by$wt_strategy." 506 dropsave 507 exit 0 508fi 509 510# Pick the result from the best strategy and have the user fix it up. 511case "$best_strategy" in 512'') 513 restorestate 514 case "$use_strategies" in 515 ?*''?*) 516 echo >&2 "No merge strategy handled the merge." 517 ;; 518 *) 519 echo >&2 "Merge with strategy$use_strategiesfailed." 520 ;; 521 esac 522 exit 2 523 ;; 524"$wt_strategy") 525 # We already have its result in the working tree. 526 ;; 527*) 528 echo "Rewinding the tree to pristine..." 529 restorestate 530 echo "Using the$best_strategyto prepare resolving by hand." 531 git-merge-$best_strategy$common-- "$head_arg" "$@" 532 ;; 533esac 534 535if test "$squash" = t 536then 537 finish 538else 539 for remote 540 do 541 echo$remote 542 done >"$GIT_DIR/MERGE_HEAD" 543 printf '%s\n' "$merge_msg" >"$GIT_DIR/MERGE_MSG" 544fi 545 546if test "$merge_was_ok" = t 547then 548 echo >&2 \ 549 "Automatic merge went well; stopped before committing as requested" 550 exit 0 551else 552 { 553 echo ' 554Conflicts: 555' 556 git ls-files --unmerged | 557 sed -e 's/^[^ ]* / /' | 558 uniq 559 } >>"$GIT_DIR/MERGE_MSG" 560 git rerere 561 die "Automatic merge failed; fix conflicts and then commit the result." 562fi