SubmittingPatches: document how to reference previous commits

diff --git a/contrib/workdir/git-new-workdir b/contrib/workdir/git-new-workdir
index 9877b98508497c9377876bd08e8f130660b9ba05..888c34a5215258ad7d5715771f92ab58f3efd363 100755 (executable)
--- a/contrib/workdir/git-new-workdir
+++ b/contrib/workdir/git-new-workdir
@@ -10,6 +10,10 @@ die () {
        exit 128
 }
 
+failed () {
+       die "unable to create new workdir '$new_workdir'!"
+}
+
 if test $# -lt 2 || test $# -gt 3
 then
        usage "$0 <repository> <new_workdir> [<branch>]"
@@ -20,38 +24,82 @@ new_workdir=$2
 branch=$3
 
 # want to make sure that what is pointed to has a .git directory ...
-test -d "$orig_git/.git" || die "\"$orig_git\" is not a git repository!"
+git_dir=$(cd "$orig_git" 2>/dev/null &&
+  git rev-parse --git-dir 2>/dev/null) ||
+  die "Not a git repository: \"$orig_git\""
+
+case "$git_dir" in
+.git)
+       git_dir="$orig_git/.git"
+       ;;
+.)
+       git_dir=$orig_git
+       ;;
+esac
+
+# don't link to a configured bare repository
+isbare=$(git --git-dir="$git_dir" config --bool --get core.bare)
+if test ztrue = "z$isbare"
+then
+       die "\"$git_dir\" has core.bare set to true," \
+               " remove from \"$git_dir/config\" to use $0"
+fi
 
 # don't link to a workdir
-if test -L "$orig_git/.git/config"
+if test -h "$git_dir/config"
 then
        die "\"$orig_git\" is a working directory only, please specify" \
                "a complete repository."
 fi
 
-# make sure the the links use full paths
-orig_git=$(cd "$orig_git"; pwd)
+# make sure the links in the workdir have full paths to the original repo
+git_dir=$(cd "$git_dir" && pwd) || exit 1
 
-# create the workdir
-mkdir -p "$new_workdir/.git" || die "unable to create \"$new_workdir\"!"
+# don't recreate a workdir over an existing directory, unless it's empty
+if test -d "$new_workdir"
+then
+       if test $(ls -a1 "$new_workdir/." | wc -l) -ne 2
+       then
+               die "destination directory '$new_workdir' is not empty."
+       fi
+       cleandir="$new_workdir/.git"
+else
+       cleandir="$new_workdir"
+fi
 
-# create the links to the original repo.  explictly exclude index, HEAD and
+mkdir -p "$new_workdir/.git" || failed
+cleandir=$(cd "$cleandir" && pwd) || failed
+
+cleanup () {
+       rm -rf "$cleandir"
+}
+siglist="0 1 2 15"
+trap cleanup $siglist
+
+# create the links to the original repo.  explicitly exclude index, HEAD and
 # logs/HEAD from the list since they are purely related to the current working
 # directory, and should not be shared.
-for x in config refs logs/refs objects info hooks packed-refs remotes rr-cache
+for x in config refs logs/refs objects info hooks packed-refs remotes rr-cache svn
 do
+       # create a containing directory if needed
        case $x in
        */*)
-               mkdir -p "$(dirname "$new_workdir/.git/$x")"
+               mkdir -p "$new_workdir/.git/${x%/*}"
                ;;
        esac
-       ln -s "$orig_git/.git/$x" "$new_workdir/.git/$x"
+
+       ln -s "$git_dir/$x" "$new_workdir/.git/$x" || failed
 done
 
-# now setup the workdir
-cd "$new_workdir"
+# commands below this are run in the context of the new workdir
+cd "$new_workdir" || failed
+
 # copy the HEAD from the original repository as a default branch
-cp "$orig_git/.git/HEAD" .git/HEAD
-# checkout the branch (either the same as HEAD from the original repository, or
-# the one that was asked for)
+cp "$git_dir/HEAD" .git/HEAD || failed
+
+# the workdir is set up.  if the checkout fails, the user can fix it.
+trap - $siglist
+
+# checkout the branch (either the same as HEAD from the original repository,
+# or the one that was asked for)
 git checkout -f $branch