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] [--[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 . 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= no_ff=
  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=$1
  27                 ;;
  28         --no-c|--no-co|--no-com|--no-comm|--no-commi|--no-commit)
  29                 no_commit=--no-commit ;;
  30         --c|--co|--com|--comm|--commi|--commit)
  31                 no_commit=--commit ;;
  32         --sq|--squ|--squa|--squas|--squash)
  33                 squash=--squash ;;
  34         --no-sq|--no-squ|--no-squa|--no-squas|--no-squash)
  35                 squash=--no-squash ;;
  36         --ff)
  37                 no_ff=--ff ;;
  38         --no-ff)
  39                 no_ff=--no-ff ;;
  40         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
  41                 --strateg=*|--strategy=*|\
  42         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
  43                 case "$#,$1" in
  44                 *,*=*)
  45                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
  46                 1,*)
  47                         usage ;;
  48                 *)
  49                         strategy="$2"
  50                         shift ;;
  51                 esac
  52                 strategy_args="${strategy_args}-s $strategy "
  53                 ;;
  54         -h|--h|--he|--hel|--help)
  55                 usage
  56                 ;;
  57         *)
  58                 # Pass thru anything that may be meant for fetch.
  59                 break
  60                 ;;
  61         esac
  62         shift
  63 done
  64
  65 orig_head=$(git rev-parse --verify HEAD 2>/dev/null)
  66 git-fetch --update-head-ok "$@" || exit 1
  67
  68 curr_head=$(git rev-parse --verify HEAD 2>/dev/null)
  69 if test "$curr_head" != "$orig_head"
  70 then
  71         # The fetch involved updating the current branch.
  72
  73         # The working tree and the index file is still based on the
  74         # $orig_head commit, but we are merging into $curr_head.
  75         # First update the working tree to match $curr_head.
  76
  77         echo >&2 "Warning: fetch updated the current branch head."
  78         echo >&2 "Warning: fast forwarding your working tree from"
  79         echo >&2 "Warning: commit $orig_head."
  80         git update-index --refresh 2>/dev/null
  81         git read-tree -u -m "$orig_head" "$curr_head" ||
  82                 die 'Cannot fast-forward your working tree.
  83 After making sure that you saved anything precious from
  84 $ git diff '$orig_head'
  85 output, run
  86 $ git reset --hard
  87 to recover.'
  88
  89 fi
  90
  91 merge_head=$(sed -e '/  not-for-merge   /d' \
  92         -e 's/  .*//' "$GIT_DIR"/FETCH_HEAD | \
  93         tr '\012' ' ')
  94
  95 case "$merge_head" in
  96 '')
  97         curr_branch=$(git symbolic-ref -q HEAD)
  98         case $? in
  99           0) ;;
 100           1) echo >&2 "You are not currently on a branch; you must explicitly"
 101              echo >&2 "specify which branch you wish to merge:"
 102              echo >&2 "  git pull <remote> <branch>"
 103              exit 1;;
 104           *) exit $?;;
 105         esac
 106         curr_branch=${curr_branch#refs/heads/}
 107
 108         echo >&2 "You asked me to pull without telling me which branch you"
 109         echo >&2 "want to merge with, and 'branch.${curr_branch}.merge' in"
 110         echo >&2 "your configuration file does not tell me either.  Please"
 111         echo >&2 "name which branch you want to merge on the command line and"
 112         echo >&2 "try again (e.g. 'git pull <repository> <refspec>')."
 113         echo >&2 "See git-pull(1) for details on the refspec."
 114         echo >&2
 115         echo >&2 "If you often merge with the same branch, you may want to"
 116         echo >&2 "configure the following variables in your configuration"
 117         echo >&2 "file:"
 118         echo >&2
 119         echo >&2 "    branch.${curr_branch}.remote = <nickname>"
 120         echo >&2 "    branch.${curr_branch}.merge = <remote-ref>"
 121         echo >&2 "    remote.<nickname>.url = <url>"
 122         echo >&2 "    remote.<nickname>.fetch = <refspec>"
 123         echo >&2
 124         echo >&2 "See git-config(1) for details."
 125         exit 1
 126         ;;
 127 ?*' '?*)
 128         if test -z "$orig_head"
 129         then
 130                 echo >&2 "Cannot merge multiple branches into empty head"
 131                 exit 1
 132         fi
 133         ;;
 134 esac
 135
 136 if test -z "$orig_head"
 137 then
 138         git update-ref -m "initial pull" HEAD $merge_head "" &&
 139         git read-tree --reset -u HEAD || exit 1
 140         exit
 141 fi
 142
 143 merge_name=$(git fmt-merge-msg <"$GIT_DIR/FETCH_HEAD") || exit
 144 exec git-merge $no_summary $no_commit $squash $no_ff $strategy_args \
 145         "$merge_name" HEAD $merge_head