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-summary] [--no-commit] [-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 . git-sh-setup
  11 set_reflog_action "pull $*"
  12 require_work_tree
  13 cd_to_toplevel
  14
  15 test -z "$(git ls-files -u)" ||
  16         die "You are in the middle of a conflicted merge."
  17
  18 strategy_args= no_summary= no_commit= squash=
  19 while :
  20 do
  21         case "$1" in
  22         -n|--n|--no|--no-|--no-s|--no-su|--no-sum|--no-summ|\
  23                 --no-summa|--no-summar|--no-summary)
  24                 no_summary=-n ;;
  25         --summary)
  26                 no_summary=$1
  27                 ;;
  28         --no-c|--no-co|--no-com|--no-comm|--no-commi|--no-commit)
  29                 no_commit=--no-commit ;;
  30         --sq|--squ|--squa|--squas|--squash)
  31                 squash=--squash ;;
  32         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
  33                 --strateg=*|--strategy=*|\
  34         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
  35                 case "$#,$1" in
  36                 *,*=*)
  37                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
  38                 1,*)
  39                         usage ;;
  40                 *)
  41                         strategy="$2"
  42                         shift ;;
  43                 esac
  44                 strategy_args="${strategy_args}-s $strategy "
  45                 ;;
  46         -h|--h|--he|--hel|--help)
  47                 usage
  48                 ;;
  49         *)
  50                 # Pass thru anything that may be meant for fetch.
  51                 break
  52                 ;;
  53         esac
  54         shift
  55 done
  56
  57 orig_head=$(git rev-parse --verify HEAD 2>/dev/null)
  58 git-fetch --update-head-ok "$@" || exit 1
  59
  60 curr_head=$(git rev-parse --verify HEAD 2>/dev/null)
  61 if test "$curr_head" != "$orig_head"
  62 then
  63         # The fetch involved updating the current branch.
  64
  65         # The working tree and the index file is still based on the
  66         # $orig_head commit, but we are merging into $curr_head.
  67         # First update the working tree to match $curr_head.
  68
  69         echo >&2 "Warning: fetch updated the current branch head."
  70         echo >&2 "Warning: fast forwarding your working tree from"
  71         echo >&2 "Warning: commit $orig_head."
  72         git update-index --refresh 2>/dev/null
  73         git read-tree -u -m "$orig_head" "$curr_head" ||
  74                 die 'Cannot fast-forward your working tree.
  75 After making sure that you saved anything precious from
  76 $ git diff '$orig_head'
  77 output, run
  78 $ git reset --hard
  79 to recover.'
  80
  81 fi
  82
  83 merge_head=$(sed -e '/  not-for-merge   /d' \
  84         -e 's/  .*//' "$GIT_DIR"/FETCH_HEAD | \
  85         tr '\012' ' ')
  86
  87 case "$merge_head" in
  88 '')
  89         curr_branch=$(git symbolic-ref -q HEAD)
  90         case $? in
  91           0) ;;
  92           1) echo >&2 "You are not currently on a branch; you must explicitly"
  93              echo >&2 "specify which branch you wish to merge:"
  94              echo >&2 "  git pull <remote> <branch>"
  95              exit 1;;
  96           *) exit $?;;
  97         esac
  98         curr_branch=${curr_branch#refs/heads/}
  99
 100         echo >&2 "You asked me to pull without telling me which branch you"
 101         echo >&2 "want to merge with, and 'branch.${curr_branch}.merge' in"
 102         echo >&2 "your configuration file does not tell me either.  Please"
 103         echo >&2 "name which branch you want to merge on the command line and"
 104         echo >&2 "try again (e.g. 'git pull <repository> <refspec>')."
 105         echo >&2 "See git-pull(1) for details on the refspec."
 106         echo >&2
 107         echo >&2 "If you often merge with the same branch, you may want to"
 108         echo >&2 "configure the following variables in your configuration"
 109         echo >&2 "file:"
 110         echo >&2
 111         echo >&2 "    branch.${curr_branch}.remote = <nickname>"
 112         echo >&2 "    branch.${curr_branch}.merge = <remote-ref>"
 113         echo >&2 "    remote.<nickname>.url = <url>"
 114         echo >&2 "    remote.<nickname>.fetch = <refspec>"
 115         echo >&2
 116         echo >&2 "See git-config(1) for details."
 117         exit 1
 118         ;;
 119 ?*' '?*)
 120         if test -z "$orig_head"
 121         then
 122                 echo >&2 "Cannot merge multiple branches into empty head"
 123                 exit 1
 124         fi
 125         ;;
 126 esac
 127
 128 if test -z "$orig_head"
 129 then
 130         git update-ref -m "initial pull" HEAD $merge_head "" &&
 131         git read-tree --reset -u HEAD || exit 1
 132         exit
 133 fi
 134
 135 merge_name=$(git fmt-merge-msg <"$GIT_DIR/FETCH_HEAD") || exit
 136 exec git-merge $no_summary $no_commit $squash $strategy_args \
 137         "$merge_name" HEAD $merge_head