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_SAVE"||exit1 32} 33 34savestate() { 35# Stash away any local modifications. 36 git diff-index -z --name-only$head| 37cpio-0 -o>"$GIT_DIR/MERGE_SAVE" 38} 39 40restorestate() { 41iftest -f"$GIT_DIR/MERGE_SAVE" 42then 43 git reset--hard$head>/dev/null 44cpio-iuv<"$GIT_DIR/MERGE_SAVE" 45 git update-index --refresh>/dev/null 46fi 47} 48 49finish_up_to_date () { 50case"$squash"in 51 t) 52echo"$1(nothing to squash)";; 53'') 54echo"$1";; 55esac 56 dropsave 57} 58 59squash_message () { 60echo Squashed commit of the following: 61echo 62 git log --no-merges ^"$head"$remoteheads 63} 64 65finish () { 66iftest''="$2" 67then 68 rlogm="$GIT_REFLOG_ACTION" 69else 70echo"$2" 71 rlogm="$GIT_REFLOG_ACTION:$2" 72fi 73case"$squash"in 74 t) 75echo"Squash commit -- not updating HEAD" 76 squash_message >"$GIT_DIR/SQUASH_MSG" 77;; 78'') 79case"$merge_msg"in 80'') 81echo"No merge message -- not updating HEAD" 82;; 83*) 84 git update-ref -m"$rlogm" HEAD "$1""$head"||exit1 85 git gc --auto 86;; 87esac 88;; 89esac 90case"$1"in 91'') 92;; 93 ?*) 94iftest"$show_diffstat"= t 95then 96# We want color (if set), but no pager 97 GIT_PAGER='' git diff--stat --summary -M"$head""$1" 98fi 99;; 100esac 101 102# Run a post-merge hook 103iftest -x"$GIT_DIR"/hooks/post-merge 104then 105case"$squash"in 106 t) 107"$GIT_DIR"/hooks/post-merge1 108;; 109'') 110"$GIT_DIR"/hooks/post-merge0 111;; 112esac 113fi 114} 115 116merge_name () { 117 remote="$1" 118 rh=$(git rev-parse --verify "$remote^0" 2>/dev/null)||return 119 bh=$(git show-ref -s --verify "refs/heads/$remote" 2>/dev/null) 120iftest"$rh"="$bh" 121then 122echo"$rhbranch '$remote' of ." 123elif truname=$(expr "$remote" : '\(.*\)~[1-9][0-9]*$') && 124 git show-ref -q --verify "refs/heads/$truname" 2>/dev/null 125 then 126 echo "$rhbranch '$truname' (early part) of ." 127 elif test "$remote" = "FETCH_HEAD" -a -r "$GIT_DIR/FETCH_HEAD" 128 then 129 sed -e 's/ not-for-merge/ /' -e 1q \ 130 "$GIT_DIR/FETCH_HEAD" 131 else 132 echo "$rhcommit '$remote'" 133 fi 134} 135 136parse_option () { 137 case "$1" in 138 -n|--n|--no|--no-|--no-s|--no-su|--no-sum|--no-summ|\ 139 --no-summa|--no-summar|--no-summary) 140 show_diffstat=false ;; 141 --summary) 142 show_diffstat=t ;; 143 --sq|--squ|--squa|--squas|--squash) 144 allow_fast_forward=t squash=t no_commit=t ;; 145 --no-sq|--no-squ|--no-squa|--no-squas|--no-squash) 146 allow_fast_forward=t squash= no_commit= ;; 147 --c|--co|--com|--comm|--commi|--commit) 148 allow_fast_forward=t squash= no_commit= ;; 149 --no-c|--no-co|--no-com|--no-comm|--no-commi|--no-commit) 150 allow_fast_forward=t squash= no_commit=t ;; 151 --ff) 152 allow_fast_forward=t squash= no_commit= ;; 153 --no-ff) 154 allow_fast_forward=false squash= no_commit= ;; 155 -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\ 156 --strateg=*|--strategy=*|\ 157 -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy) 158 case "$#,$1" in 159 *,*=*) 160 strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;; 161 1,*) 162 usage ;; 163 *) 164 strategy="$2" 165 shift ;; 166 esac 167 case "$all_strategies" in 168 *"$strategy"*) 169 use_strategies="$use_strategies$strategy" ;; 170 *) 171 die "available strategies are:$all_strategies" ;; 172 esac 173 ;; 174 -m=*|--m=*|--me=*|--mes=*|--mess=*|--messa=*|--messag=*|--message=*) 175 merge_msg=`expr "z$1" : 'z-[^=]*=\(.*\)'` 176 have_message=t 177 ;; 178 -m|--m|--me|--mes|--mess|--messa|--messag|--message) 179 shift 180 case "$#" in 181 1) usage ;; 182 esac 183 merge_msg="$1" 184 have_message=t 185 ;; 186 -*) usage ;; 187 *) return 1 ;; 188 esac 189 shift 190 args_left=$# 191} 192 193parse_config () { 194 while test$#-gt 0 195 do 196 parse_option "$@" || usage 197 while test$args_left-lt$# 198 do 199 shift 200 done 201 done 202} 203 204test$#!= 0 || usage 205 206have_message= 207 208if branch=$(git-symbolic-ref -q HEAD) 209then 210 mergeopts=$(git config "branch.${branch#refs/heads/}.mergeoptions") 211 if test -n "$mergeopts" 212 then 213 parse_config$mergeopts 214 fi 215fi 216 217while parse_option "$@" 218do 219 while test$args_left-lt$# 220 do 221 shift 222 done 223done 224 225if test -z "$show_diffstat"; then 226 test "$(git config --bool merge.diffstat)" = false && show_diffstat=false 227 test -z "$show_diffstat" && show_diffstat=t 228fi 229 230# This could be traditional "merge <msg> HEAD <commit>..." and the 231# way we can tell it is to see if the second token is HEAD, but some 232# people might have misused the interface and used a committish that 233# is the same as HEAD there instead. Traditional format never would 234# have "-m" so it is an additional safety measure to check for it. 235 236if test -z "$have_message" && 237 second_token=$(git rev-parse --verify "$2^0" 2>/dev/null)&& 238 head_commit=$(git rev-parse --verify "HEAD" 2>/dev/null)&& 239 test "$second_token" = "$head_commit" 240then 241 merge_msg="$1" 242 shift 243 head_arg="$1" 244 shift 245elif ! git rev-parse --verify HEAD >/dev/null 2>&1 246then 247 # If the merged head is a valid one there is no reason to 248 # forbid "git merge" into a branch yet to be born. We do 249 # the same for "git pull". 250 if test 1 -ne$# 251 then 252 echo >&2 "Can merge only exactly one commit into empty head" 253 exit 1 254 fi 255 256 rh=$(git rev-parse --verify "$1^0")|| 257 die "$1- not something we can merge" 258 259 git update-ref -m "initial pull" HEAD "$rh" "" && 260 git read-tree --reset -u HEAD 261 exit 262 263else 264 # We are invoked directly as the first-class UI. 265 head_arg=HEAD 266 267 # All the rest are the commits being merged; prepare 268 # the standard merge summary message to be appended to 269 # the given message. If remote is invalid we will die 270 # later in the common codepath so we discard the error 271 # in this loop. 272 merge_name=$(for remote 273 do 274 merge_name "$remote" 275 done | git fmt-merge-msg 276 ) 277 merge_msg="${merge_msg:+$merge_msg$LF$LF}$merge_name" 278fi 279head=$(git rev-parse --verify "$head_arg"^0)|| usage 280 281# All the rest are remote heads 282test "$#" = 0 && usage ;# we need at least one remote head. 283set_reflog_action "merge $*" 284 285remoteheads= 286for remote 287do 288 remotehead=$(git rev-parse --verify "$remote"^0 2>/dev/null)|| 289 die "$remote- not something we can merge" 290 remoteheads="${remoteheads}$remotehead" 291 eval GITHEAD_$remotehead='"$remote"' 292 export GITHEAD_$remotehead 293done 294set x$remoteheads; shift 295 296case "$use_strategies" in 297'') 298 case "$#" in 299 1) 300 var="`git config --get pull.twohead`" 301 if test -n "$var" 302 then 303 use_strategies="$var" 304 else 305 use_strategies="$default_twohead_strategies" 306 fi ;; 307 *) 308 var="`git config --get pull.octopus`" 309 if test -n "$var" 310 then 311 use_strategies="$var" 312 else 313 use_strategies="$default_octopus_strategies" 314 fi ;; 315 esac 316 ;; 317esac 318 319for s in$use_strategies 320do 321 for ss in$no_fast_forward_strategies 322 do 323 case "$s" in 324 *"$ss"*) 325 allow_fast_forward=f 326 break 327 ;; 328 esac 329 done 330 for ss in$no_trivial_strategies 331 do 332 case "$s" in 333 *"$ss"*) 334 allow_trivial_merge=f 335 break 336 ;; 337 esac 338 done 339done 340 341case "$#" in 3421) 343 common=$(git merge-base --all $head "$@") 344 ;; 345*) 346 common=$(git show-branch --merge-base $head "$@") 347 ;; 348esac 349echo "$head" >"$GIT_DIR/ORIG_HEAD" 350 351case "$allow_fast_forward,$#,$common,$no_commit" in 352?,*,'',*) 353 # No common ancestors found. We need a real merge. 354 ;; 355?,1,"$1",*) 356 # If head can reach all the merge then we are up to date. 357 # but first the most common case of merging one remote. 358 finish_up_to_date "Already up-to-date." 359 exit 0 360 ;; 361t,1,"$head",*) 362 # Again the most common case of merging one remote. 363 echo "Updating$(git rev-parse --short $head)..$(git rev-parse --short $1)" 364 git update-index --refresh 2>/dev/null 365 msg="Fast forward" 366 if test -n "$have_message" 367 then 368 msg="$msg(no commit created; -m option ignored)" 369 fi 370 new_head=$(git rev-parse --verify "$1^0")&& 371 git read-tree -v -m -u --exclude-per-directory=.gitignore$head"$new_head" && 372 finish "$new_head" "$msg" || exit 373 dropsave 374 exit 0 375 ;; 376?,1,?*"$LF"?*,*) 377 # We are not doing octopus and not fast forward. Need a 378 # real merge. 379 ;; 380?,1,*,) 381 # We are not doing octopus, not fast forward, and have only 382 # one common. 383 git update-index --refresh 2>/dev/null 384 case "$allow_trivial_merge" in 385 t) 386 # See if it is really trivial. 387 git var GIT_COMMITTER_IDENT >/dev/null || exit 388 echo "Trying really trivial in-index merge..." 389 if git read-tree --trivial -m -u -v$common$head"$1" && 390 result_tree=$(git write-tree) 391 then 392 echo "Wonderful." 393 result_commit=$( 394 printf '%s\n' "$merge_msg" | 395 git commit-tree$result_tree-p HEAD -p "$1" 396 ) || exit 397 finish "$result_commit" "In-index merge" 398 dropsave 399 exit 0 400 fi 401 echo "Nope." 402 esac 403 ;; 404*) 405 # An octopus. If we can reach all the remote we are up to date. 406 up_to_date=t 407 for remote 408 do 409 common_one=$(git merge-base --all $head $remote) 410 if test "$common_one" != "$remote" 411 then 412 up_to_date=f 413 break 414 fi 415 done 416 if test "$up_to_date" = t 417 then 418 finish_up_to_date "Already up-to-date. Yeeah!" 419 exit 0 420 fi 421 ;; 422esac 423 424# We are going to make a new commit. 425git var GIT_COMMITTER_IDENT >/dev/null || exit 426 427# At this point, we need a real merge. No matter what strategy 428# we use, it would operate on the index, possibly affecting the 429# working tree, and when resolved cleanly, have the desired tree 430# in the index -- this means that the index must be in sync with 431# the$headcommit. The strategies are responsible to ensure this. 432 433case "$use_strategies" in 434?*''?*) 435 # Stash away the local changes so that we can try more than one. 436 savestate 437 single_strategy=no 438 ;; 439*) 440 rm -f "$GIT_DIR/MERGE_SAVE" 441 single_strategy=yes 442 ;; 443esac 444 445result_tree= best_cnt=-1 best_strategy= wt_strategy= 446merge_was_ok= 447for strategy in$use_strategies 448do 449 test "$wt_strategy" = '' || { 450 echo "Rewinding the tree to pristine..." 451 restorestate 452 } 453 case "$single_strategy" in 454 no) 455 echo "Trying merge strategy$strategy..." 456 ;; 457 esac 458 459 # Remember which strategy left the state in the working tree 460 wt_strategy=$strategy 461 462 git-merge-$strategy$common-- "$head_arg" "$@" 463 exit=$? 464 if test "$no_commit" = t && test "$exit" = 0 465 then 466 merge_was_ok=t 467 exit=1 ;# pretend it left conflicts. 468 fi 469 470 test "$exit" = 0 || { 471 472 # The backend exits with 1 when conflicts are left to be resolved, 473 # with 2 when it does not handle the given merge at all. 474 475 if test "$exit" -eq 1 476 then 477 cnt=`{ 478 git diff-files --name-only 479 git ls-files --unmerged 480 } | wc -l` 481 if test$best_cnt-le 0 -o$cnt-le$best_cnt 482 then 483 best_strategy=$strategy 484 best_cnt=$cnt 485 fi 486 fi 487 continue 488 } 489 490 # Automerge succeeded. 491 result_tree=$(git write-tree)&& break 492done 493 494# If we have a resulting tree, that means the strategy module 495# auto resolved the merge cleanly. 496if test '' != "$result_tree" 497then 498 if test "$allow_fast_forward" = "t" 499 then 500 parents=$(git show-branch --independent "$head" "$@") 501 else 502 parents=$(git rev-parse "$head" "$@") 503 fi 504 parents=$(echo "$parents" | sed -e 's/^/-p /') 505 result_commit=$(printf '%s\n' "$merge_msg" | git commit-tree $result_tree $parents)|| exit 506 finish "$result_commit" "Merge made by$wt_strategy." 507 dropsave 508 exit 0 509fi 510 511# Pick the result from the best strategy and have the user fix it up. 512case "$best_strategy" in 513'') 514 restorestate 515 case "$use_strategies" in 516 ?*''?*) 517 echo >&2 "No merge strategy handled the merge." 518 ;; 519 *) 520 echo >&2 "Merge with strategy$use_strategiesfailed." 521 ;; 522 esac 523 exit 2 524 ;; 525"$wt_strategy") 526 # We already have its result in the working tree. 527 ;; 528*) 529 echo "Rewinding the tree to pristine..." 530 restorestate 531 echo "Using the$best_strategyto prepare resolving by hand." 532 git-merge-$best_strategy$common-- "$head_arg" "$@" 533 ;; 534esac 535 536if test "$squash" = t 537then 538 finish 539else 540 for remote 541 do 542 echo$remote 543 done >"$GIT_DIR/MERGE_HEAD" 544 printf '%s\n' "$merge_msg" >"$GIT_DIR/MERGE_MSG" 545fi 546 547if test "$merge_was_ok" = t 548then 549 echo >&2 \ 550 "Automatic merge went well; stopped before committing as requested" 551 exit 0 552else 553 { 554 echo ' 555Conflicts: 556' 557 git ls-files --unmerged | 558 sed -e 's/^[^ ]* / /' | 559 uniq 560 } >>"$GIT_DIR/MERGE_MSG" 561 git rerere 562 die "Automatic merge failed; fix conflicts and then commit the result." 563fi