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] [-s strategy]... [<fetch-options>] <repo> <head>...'
   8 LONG_USAGE='Fetch one or more remote refs and merge it/them into the current HEAD.'
   9 SUBDIRECTORY_OK=Yes
  10 OPTIONS_SPEC=
  11 . git-sh-setup
  12 set_reflog_action "pull $*"
  13 require_work_tree
  14 cd_to_toplevel
  15
  16 test -z "$(git ls-files -u)" ||
  17         die "You are in the middle of a conflicted merge."
  18
  19 strategy_args= diffstat= no_commit= squash= no_ff= log_arg= verbosity=
  20 curr_branch=$(git symbolic-ref -q HEAD)
  21 curr_branch_short=$(echo "$curr_branch" | sed "s|refs/heads/||")
  22 rebase=$(git config --bool branch.$curr_branch_short.rebase)
  23 while :
  24 do
  25         case "$1" in
  26         -q|--quiet)
  27                 verbosity="$verbosity -q" ;;
  28         -v|--verbose)
  29                 verbosity="$verbosity -v" ;;
  30         -n|--no-stat|--no-summary)
  31                 diffstat=--no-stat ;;
  32         --stat|--summary)
  33                 diffstat=--stat ;;
  34         --log|--no-log)
  35                 log_arg=$1 ;;
  36         --no-c|--no-co|--no-com|--no-comm|--no-commi|--no-commit)
  37                 no_commit=--no-commit ;;
  38         --c|--co|--com|--comm|--commi|--commit)
  39                 no_commit=--commit ;;
  40         --sq|--squ|--squa|--squas|--squash)
  41                 squash=--squash ;;
  42         --no-sq|--no-squ|--no-squa|--no-squas|--no-squash)
  43                 squash=--no-squash ;;
  44         --ff)
  45                 no_ff=--ff ;;
  46         --no-ff)
  47                 no_ff=--no-ff ;;
  48         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
  49                 --strateg=*|--strategy=*|\
  50         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
  51                 case "$#,$1" in
  52                 *,*=*)
  53                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
  54                 1,*)
  55                         usage ;;
  56                 *)
  57                         strategy="$2"
  58                         shift ;;
  59                 esac
  60                 strategy_args="${strategy_args}-s $strategy "
  61                 ;;
  62         -r|--r|--re|--reb|--reba|--rebas|--rebase)
  63                 rebase=true
  64                 ;;
  65         --no-r|--no-re|--no-reb|--no-reba|--no-rebas|--no-rebase)
  66                 rebase=false
  67                 ;;
  68         -h|--h|--he|--hel|--help)
  69                 usage
  70                 ;;
  71         *)
  72                 # Pass thru anything that may be meant for fetch.
  73                 break
  74                 ;;
  75         esac
  76         shift
  77 done
  78
  79 error_on_no_merge_candidates () {
  80         exec >&2
  81         for opt
  82         do
  83                 case "$opt" in
  84                 -t|--t|--ta|--tag|--tags)
  85                         echo "Fetching tags only, you probably meant:"
  86                         echo "  git fetch --tags"
  87                         exit 1
  88                 esac
  89         done
  90
  91         curr_branch=${curr_branch#refs/heads/}
  92
  93         if [ -z "$curr_branch" ]; then
  94                 echo "You are not currently on a branch, so I cannot use any"
  95                 echo "'branch.<branchname>.merge' in your configuration file."
  96                 echo "Please specify which branch you want to merge on the command"
  97                 echo "line and try again (e.g. 'git pull <repository> <refspec>')."
  98                 echo "See git-pull(1) for details."
  99         else
 100                 echo "You asked me to pull without telling me which branch you"
 101                 echo "want to merge with, and 'branch.${curr_branch}.merge' in"
 102                 echo "your configuration file does not tell me either.  Please"
 103                 echo "specify which branch you want to merge on the command line and"
 104                 echo "try again (e.g. 'git pull <repository> <refspec>')."
 105                 echo "See git-pull(1) for details."
 106                 echo
 107                 echo "If you often merge with the same branch, you may want to"
 108                 echo "configure the following variables in your configuration"
 109                 echo "file:"
 110                 echo
 111                 echo "    branch.${curr_branch}.remote = <nickname>"
 112                 echo "    branch.${curr_branch}.merge = <remote-ref>"
 113                 echo "    remote.<nickname>.url = <url>"
 114                 echo "    remote.<nickname>.fetch = <refspec>"
 115                 echo
 116                 echo "See git-config(1) for details."
 117         fi
 118         exit 1
 119 }
 120
 121 test true = "$rebase" && {
 122         if ! git rev-parse -q --verify HEAD >/dev/null
 123         then
 124                 # On an unborn branch
 125                 if test -f "$GIT_DIR/index"
 126                 then
 127                         die "updating an unborn branch with changes added to the index"
 128                 fi
 129         else
 130                 git update-index --ignore-submodules --refresh &&
 131                 git diff-files --ignore-submodules --quiet &&
 132                 git diff-index --ignore-submodules --cached --quiet HEAD -- ||
 133                 die "refusing to pull with rebase: your working tree is not up-to-date"
 134         fi
 135         oldremoteref= &&
 136         . git-parse-remote &&
 137         remoteref="$(get_remote_merge_branch "$@" 2>/dev/null)" &&
 138         oldremoteref="$(git rev-parse -q --verify "$remoteref")" &&
 139         for reflog in $(git rev-list -g $remoteref 2>/dev/null)
 140         do
 141                 if test "$reflog" = "$(git merge-base $reflog $curr_branch)"
 142                 then
 143                         oldremoteref="$reflog"
 144                         break
 145                 fi
 146         done
 147 }
 148 orig_head=$(git rev-parse -q --verify HEAD)
 149 git fetch $verbosity --update-head-ok "$@" || exit 1
 150
 151 curr_head=$(git rev-parse -q --verify HEAD)
 152 if test -n "$orig_head" && test "$curr_head" != "$orig_head"
 153 then
 154         # The fetch involved updating the current branch.
 155
 156         # The working tree and the index file is still based on the
 157         # $orig_head commit, but we are merging into $curr_head.
 158         # First update the working tree to match $curr_head.
 159
 160         echo >&2 "Warning: fetch updated the current branch head."
 161         echo >&2 "Warning: fast forwarding your working tree from"
 162         echo >&2 "Warning: commit $orig_head."
 163         git update-index -q --refresh
 164         git read-tree -u -m "$orig_head" "$curr_head" ||
 165                 die 'Cannot fast-forward your working tree.
 166 After making sure that you saved anything precious from
 167 $ git diff '$orig_head'
 168 output, run
 169 $ git reset --hard
 170 to recover.'
 171
 172 fi
 173
 174 merge_head=$(sed -e '/  not-for-merge   /d' \
 175         -e 's/  .*//' "$GIT_DIR"/FETCH_HEAD | \
 176         tr '\012' ' ')
 177
 178 case "$merge_head" in
 179 '')
 180         case $? in
 181         0) error_on_no_merge_candidates "$@";;
 182         1) echo >&2 "You are not currently on a branch; you must explicitly"
 183            echo >&2 "specify which branch you wish to merge:"
 184            echo >&2 "  git pull <remote> <branch>"
 185            exit 1;;
 186         *) exit $?;;
 187         esac
 188         ;;
 189 ?*' '?*)
 190         if test -z "$orig_head"
 191         then
 192                 die "Cannot merge multiple branches into empty head"
 193         fi
 194         if test true = "$rebase"
 195         then
 196                 die "Cannot rebase onto multiple branches"
 197         fi
 198         ;;
 199 esac
 200
 201 if test -z "$orig_head"
 202 then
 203         git update-ref -m "initial pull" HEAD $merge_head "$curr_head" &&
 204         git read-tree --reset -u HEAD || exit 1
 205         exit
 206 fi
 207
 208 merge_name=$(git fmt-merge-msg $log_arg <"$GIT_DIR/FETCH_HEAD") || exit
 209 test true = "$rebase" &&
 210         exec git-rebase $diffstat $strategy_args --onto $merge_head \
 211         ${oldremoteref:-$merge_head}
 212 exec git-merge $diffstat $no_commit $squash $no_ff $log_arg $strategy_args \
 213         "$merge_name" HEAD $merge_head $verbosity