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