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 case "$#,$1" in 0) break ;; *,-*) ;; *) break ;; esac
  20 do
  21         case "$1" in
  22         -n|--n|--no|--no-|--no-s|--no-su|--no-sum|--no-summ|\
  23                 --no-summa|--no-summar|--no-summary)
  24                 no_summary=-n ;;
  25         --no-c|--no-co|--no-com|--no-comm|--no-commi|--no-commit)
  26                 no_commit=--no-commit ;;
  27         --sq|--squ|--squa|--squas|--squash)
  28                 squash=--squash ;;
  29         -s=*|--s=*|--st=*|--str=*|--stra=*|--strat=*|--strate=*|\
  30                 --strateg=*|--strategy=*|\
  31         -s|--s|--st|--str|--stra|--strat|--strate|--strateg|--strategy)
  32                 case "$#,$1" in
  33                 *,*=*)
  34                         strategy=`expr "z$1" : 'z-[^=]*=\(.*\)'` ;;
  35                 1,*)
  36                         usage ;;
  37                 *)
  38                         strategy="$2"
  39                         shift ;;
  40                 esac
  41                 strategy_args="${strategy_args}-s $strategy "
  42                 ;;
  43         -h|--h|--he|--hel|--help)
  44                 usage
  45                 ;;
  46         -*)
  47                 # Pass thru anything that is meant for fetch.
  48                 break
  49                 ;;
  50         esac
  51         shift
  52 done
  53
  54 orig_head=$(git-rev-parse --verify HEAD 2>/dev/null)
  55 git-fetch --update-head-ok "$@" || exit 1
  56
  57 curr_head=$(git-rev-parse --verify HEAD 2>/dev/null)
  58 if test "$curr_head" != "$orig_head"
  59 then
  60         # The fetch involved updating the current branch.
  61
  62         # The working tree and the index file is still based on the
  63         # $orig_head commit, but we are merging into $curr_head.
  64         # First update the working tree to match $curr_head.
  65
  66         echo >&2 "Warning: fetch updated the current branch head."
  67         echo >&2 "Warning: fast forwarding your working tree from"
  68         echo >&2 "Warning: commit $orig_head."
  69         git-update-index --refresh 2>/dev/null
  70         git-read-tree -u -m "$orig_head" "$curr_head" ||
  71                 die 'Cannot fast-forward your working tree.
  72 After making sure that you saved anything precious from
  73 $ git diff '$orig_head'
  74 output, run
  75 $ git reset --hard
  76 to recover.'
  77
  78 fi
  79
  80 merge_head=$(sed -e '/  not-for-merge   /d' \
  81         -e 's/  .*//' "$GIT_DIR"/FETCH_HEAD | \
  82         tr '\012' ' ')
  83
  84 case "$merge_head" in
  85 '')
  86         curr_branch=$(git-symbolic-ref -q HEAD)
  87         case $? in
  88           0) ;;
  89           1) echo >&2 "You are not currently on a branch; you must explicitly"
  90              echo >&2 "specify which branch you wish to merge:"
  91              echo >&2 "  git pull <remote> <branch>"
  92              exit 1;;
  93           *) exit $?;;
  94         esac
  95         curr_branch=${curr_branch#refs/heads/}
  96
  97         echo >&2 "Warning: No merge candidate found because value of config option
  98          \"branch.${curr_branch}.merge\" does not match any remote branch fetched."
  99         echo >&2 "No changes."
 100         exit 0
 101         ;;
 102 ?*' '?*)
 103         if test -z "$orig_head"
 104         then
 105                 echo >&2 "Cannot merge multiple branches into empty head"
 106                 exit 1
 107         fi
 108         ;;
 109 esac
 110
 111 if test -z "$orig_head"
 112 then
 113         git-update-ref -m "initial pull" HEAD $merge_head "" &&
 114         git-read-tree --reset -u HEAD || exit 1
 115         exit
 116 fi
 117
 118 merge_name=$(git-fmt-merge-msg <"$GIT_DIR/FETCH_HEAD") || exit
 119 exec git-merge $no_summary $no_commit $squash $strategy_args \
 120         "$merge_name" HEAD $merge_head