X-Git-Url: https://git.madduck.net/code/vcsh.git/blobdiff_plain/e11ef008517996497ba413813c2fa756ac22f122..5245aa481f117049480de35d6b8eb984701ae72f:/vcsh

diff --git a/vcsh b/vcsh
index bb04b29..06f6c33 100755
--- a/vcsh
+++ b/vcsh
@@ -1,206 +1,657 @@
 #!/bin/sh
 
-[ -n "$VCSH_DEBUG" ] && set -x
+# This program is licensed under the GNU GPL version 2 or later.
+# (c) Richard "RichiH" Hartmann <richih@debian.org>, 2011-2015
+# For details, see LICENSE. To submit patches, you have to agree to
+# license your code under the GNU GPL version 2 or later.
 
+# While the following is not legally binding, the author would like to
+# explain the choice of GPLv2+ over GPLv3+.
+# The author prefers GPLv3+ over GPLv2+ but feels it's better to maintain
+# full compatibility's with Git. In case Git ever changes its licensing terms,
+# which is admittedly extremely unlikely to the point of being impossible,
+# this software will most likely follow suit.
+
+# This should always be the first line of code to facilitate debugging
+[ -n "$VCSH_DEBUG" ] && set -vx
+
+
+# If '.git-HEAD' is appended to the version, you are seeing an unreleased
+# version of vcsh; the master branch is supposed to be clean at all times
+# so you can most likely just use it nonetheless
+VERSION='1.20141026'
 SELF=$(basename $0)
 
-[ -z "$XDG_CONFIG_HOME" ] && XDG_CONFIG_HOME="$HOME/.config"
-[ -z "$VCSH_BASE" ]       && VCSH_BASE="$XDG_CONFIG_HOME/vcsh/repo.d"
-for check_directory in "$VCSH_BASE" "$HOME/.gitignore.d"
-do
-	if [ ! -d "$check_directory" ]; then
-		if [ -e "$check_directory" ]; then
-			echo "$SELF: error: $check_directory exists but is not a directory" >&2
-			exit 2
-		else
-			echo "$SELF: info: attempting to create $check_directory"
-			mkdir -p "$check_directory" || (echo "$SELF: error: could not create $check_directory" >&2; exit 2)
-		fi
+fatal() {
+	echo "$SELF: fatal: $1" >&2
+	[ -z $2 ] && exit 1
+	exit $2
+}
+
+# We need to run getops as soon as possible so we catch -d and other
+# options that will modify our behaviour.
+# Commands are handled at the end of this script.
+while getopts "c:dv" flag; do
+	if [ x"$1" = x'-d' ] || [ x"$1" = x'--debug' ]; then
+		set -vx
+		VCSH_DEBUG=1
+		echo "debug mode on"
+		echo "$SELF $VERSION"
+	elif [ x"$1" = x'-v' ]; then
+		VCSH_VERBOSE=1
+		echo "verbose mode on"
+		echo "$SELF $VERSION"
+	elif [ x"$1" = x'-c' ]; then
+		VCSH_OPTION_CONFIG=$OPTARG
 	fi
+	shift 1
 done
 
+source_all() {
+	# Source file even if it's in $PWD and does not have any slashes in it
+	case $1 in
+		*/*) . "$1";;
+		*)   . "$PWD/$1";;
+	esac;
+}
+
+
+# Read configuration and set defaults if anything's not set
+[ -n "$VCSH_DEBUG" ]                  && set -vx
+: ${XDG_CONFIG_HOME:="$HOME/.config"}
+
+# Read configuration files if there are any
+[ -r "/etc/vcsh/config" ]             && . "/etc/vcsh/config"
+[ -r "$XDG_CONFIG_HOME/vcsh/config" ] && . "$XDG_CONFIG_HOME/vcsh/config"
+if [ -n "$VCSH_OPTION_CONFIG" ]; then
+	# Source $VCSH_OPTION_CONFIG if it can be read and is in $PWD of $PATH
+	if [ -r "$VCSH_OPTION_CONFIG" ]; then
+		source_all "$VCSH_OPTION_CONFIG"
+	else
+		fatal "Can not read configuration file '$VCSH_OPTION_CONFIG'" 1
+	fi
+fi
+[ -n "$VCSH_DEBUG" ]                  && set -vx
+
+# Read defaults
+: ${VCSH_REPO_D:="$XDG_CONFIG_HOME/vcsh/repo.d"}
+: ${VCSH_HOOK_D:="$XDG_CONFIG_HOME/vcsh/hooks-enabled"}
+: ${VCSH_OVERLAY_D:="$XDG_CONFIG_HOME/vcsh/overlays-enabled"}
+: ${VCSH_BASE:="$HOME"}
+: ${VCSH_GITIGNORE:=exact}
+: ${VCSH_GITATTRIBUTES:=none}
+: ${VCSH_WORKTREE:=absolute}
+
+if [ ! "x$VCSH_GITIGNORE" = 'xexact' ] && [ ! "x$VCSH_GITIGNORE" = 'xnone' ] && [ ! "x$VCSH_GITIGNORE" = 'xrecursive' ]; then
+	fatal "'\$VCSH_GITIGNORE' must equal 'exact', 'none', or 'recursive'" 1
+fi
+
+if [ ! "x$VCSH_WORKTREE" = 'xabsolute' ] && [ ! "x$VCSH_WORKTREE" = 'xrelative' ]; then
+	fatal "'\$VCSH_WORKTREE' must equal 'absolute', or 'relative'" 1
+fi
+
+
+help() {
+	echo "usage: $SELF <options> <command>
+
+   options:
+   -c <file>            Source file
+   -d                   Enable debug mode
+   -v                   Enable verbose mode
+
+   commands:
+   clone [-b <branch>] \\
+         <remote> \\
+         [<repo>]       Clone from an existing repository
+   commit               Commit in all repositories
+   delete <repo>        Delete an existing repository
+   enter <repo>         Enter repository; spawn new instance of \$SHELL
+   foreach [<-g>]
+     <git command>      Execute a command for every repository
+   help                 Display this help text
+   init <repo>          Initialize a new repository
+   list                 List all repositories
+   list-tracked \\
+        [<repo>]        List all files tracked all or one repositories
+   list-untracked \\
+        [<-a>] [<-r>]
+        [<repo>]        List all files not tracked by all or one repositories
+   pull                 Pull from all vcsh remotes
+   push                 Push to vcsh remotes
+   rename <repo> \\
+          <newname>     Rename repository
+   run <repo> \\
+       <command>        Use this repository
+   status \\
+     [--terse] [<repo>] Show statuses of all/one vcsh repositories
+   upgrade <repo>       Upgrade repository to currently recommended settings
+   version              Print version information
+   which <substring>    Find substring in name of any tracked file
+   write-gitignore \\
+   <repo>               Write .gitignore.d/<repo> via git ls-files
+
+   <repo> <git command> Shortcut to run git commands directly
+   <repo>               Shortcut to enter repository" >&2
+}
+
 debug() {
-	[ -n "$VCSH_DEBUG" ] && echo "$SELF: debug: $1"
+	[ -n "$VCSH_DEBUG" ] && echo "$SELF: debug: $@"
 }
 
 verbose() {
-	if [ -n "$VCSH_DEBUG" ] || [ -n "$VCSH_VERBOSE" ]; then echo "$SELF: verbose: $1"; fi
+	if [ -n "$VCSH_DEBUG" ] || [ -n "$VCSH_VERBOSE" ]; then echo "$SELF: verbose: $@"; fi
 }
 
-#   use <repo>     Use this repository
-#
-#   exit              Exit vcsh mode" >&2
-help() {
-	echo "usage: $SELF <args>
+error() {
+	echo "$SELF: error: $1" >&2
+}
+
+info() {
+	echo "$SELF: info: $1"
+}
+
+clone() {
+	hook pre-clone
+	init
+	git remote add origin "$GIT_REMOTE"
+	git checkout -b "$VCSH_BRANCH" || return $?
+	git config branch."$VCSH_BRANCH".remote origin
+	git config branch."$VCSH_BRANCH".merge  refs/heads/"$VCSH_BRANCH"
+	if [ $(git ls-remote origin "$VCSH_BRANCH" 2> /dev/null | wc -l ) -lt 1 ]; then
+		info "remote is empty, not merging anything.
+  You should add files to your new repository."
+		exit
+	fi
+	git fetch origin "$VCSH_BRANCH"
+	hook pre-merge
+	git ls-tree -r --name-only origin/"$VCSH_BRANCH" | (while read object; do
+		[ -e "$object" ] &&
+			error "'$object' exists." &&
+			VCSH_CONFLICT=1
+	done
+	[ x"$VCSH_CONFLICT" = x'1' ]) &&
+		fatal "will stop after fetching and not try to merge!
+  Once this situation has been resolved, run 'vcsh $VCSH_REPO_NAME pull' to finish cloning." 17
+	git -c merge.ff=true merge origin/"$VCSH_BRANCH"
+	hook post-merge
+	hook post-clone
+	retire
+	hook post-clone-retired
+}
 
-   help              Display this help
+commit() {
+	hook pre-commit
+	for VCSH_REPO_NAME in $(list); do
+		echo "$VCSH_REPO_NAME: "
+		GIT_DIR=$VCSH_REPO_D/$VCSH_REPO_NAME.git; export GIT_DIR
+		use
+		git commit --untracked-files=no --quiet
+		VCSH_COMMAND_RETURN_CODE=$?
+		echo
+	done
+	hook post-commit
+}
+
+delete() {
+	cd "$VCSH_BASE" || fatal "could not enter '$VCSH_BASE'" 11
+	use
+	info "This operation WILL DESTROY DATA!"
+	files=$(git ls-files)
+	echo "These files will be deleted:
 
-   list              List all repos
+$files
 
-   run <repo> \\
-       <command>     Use this repository
+AGAIN, THIS WILL DELETE YOUR DATA!
+To continue, type 'Yes, do as I say'"
+	read answer
+	[ "x$answer" = 'xYes, do as I say' ] || exit 16
+	for file in $files; do
+		rm -f $file || info "could not delete '$file', continuing with deletion"
+	done
+	rm -rf "$GIT_DIR" || error "could not delete '$GIT_DIR'"
+}
 
-   init <repo>       Initialize a new repository
-   clone <remote> \\
-         [<repo>]    Clone from an existing repository
-   seed-gitignore \\
-   <repo>            Seed .gitignore.d/<repo> from git ls-files" >&2
+enter() {
+	hook pre-enter
+	use
+	$SHELL
+	hook post-enter
 }
 
-use() {
-	verbose "use() begin"
-	REPO_NAME="$1"
-	GIT_DIR="$VCSH_BASE/$REPO_NAME.git"
+foreach() {
+	hook pre-foreach
 
-	if [ ! -d "$GIT_DIR" ]; then
-		echo E: no repository found for "$REPO_NAME" >&2
-		return 2
-	fi
+	# We default to prefixing `git` to all commands passed to foreach, but
+	# allow running in general context with -g
+	command_prefix=git
+	while getopts "g" flag; do
+		if [ x"$1" = x'-g' ]; then
+			unset command_prefix
+		fi
+		shift 1
+	done
+	for VCSH_REPO_NAME in $(list); do
+		echo "$VCSH_REPO_NAME:"
+		GIT_DIR=$VCSH_REPO_D/$VCSH_REPO_NAME.git; export GIT_DIR
+		use
+		$command_prefix "$@"
+	done
+	hook post-foreach
+}
+
+git_dir_exists() {
+	[ -d "$GIT_DIR" ] || fatal "no repository found for '$VCSH_REPO_NAME'" 12
+}
 
-	export GIT_DIR
-	export GIT_WORK_TREE="$(git config --get core.worktree)"
-	export VCSH_DIRECTORY="$REPO_NAME"
-	verbose "use() end"
+hook() {
+	for hook in "$VCSH_HOOK_D/$1"* "$VCSH_HOOK_D/$VCSH_REPO_NAME.$1"*; do
+		[ -x "$hook" ] || continue
+		verbose "executing '$hook'"
+		"$hook"
+	done
 }
 
 init() {
-	verbose "init() begin"
-	[ -e "$GIT_DIR" ] &&
-		echo "$SELF: fatal: $GIT_DIR exists" &&
-		return 21
-	export GIT_WORK_TREE="$HOME"
-	mkdir -p "$GIT_WORK_TREE"
-	cd "$GIT_WORK_TREE" ||
-		(echo "$SELF: fatal: could not enter $GIT_WORK_TREE" &&
-		 exit 20) || exit 20
-	cd "$GIT_WORK_TREE"
-	git init
-	git config core.worktree     "$GIT_WORK_TREE"
-	git config core.excludesfile ".gitignore.d/$REPO_NAME"
-	touch   "$HOME/.gitignore.d/$REPO_NAME"
-	git add "$HOME/.gitignore.d/$REPO_NAME"
-	verbose "init() end"
-}
-
-leave() {
-	unset GIT_DIR
-	unset GIT_WORK_TREE
-	unset VCSH_DIRECTORY
+	hook pre-init
+	[ ! -e "$GIT_DIR" ] || fatal "'$GIT_DIR' exists" 10
+	mkdir -p "$VCSH_BASE" || fatal "could not create '$VCSH_BASE'" 50
+	cd "$VCSH_BASE" || fatal "could not enter '$VCSH_BASE'" 11
+	git init --shared=0600
+	upgrade
+	hook post-init
+}
+
+list() {
+	for repo in "$VCSH_REPO_D"/*.git; do
+		[ -d "$repo" ] && [ -r "$repo" ] && echo "$(basename "$repo" .git)"
+	done
+}
+
+get_files() {
+	GIT_DIR=$VCSH_REPO_D/$VCSH_REPO_NAME.git; export GIT_DIR
+	git ls-files
+}
+
+list_tracked() {
+	VCSH_REPO_NAME=$2; export VCSH_REPO_NAME
+	if [ -n "$VCSH_REPO_NAME" ]; then
+		get_files | list_tracked_helper
+	else
+		for VCSH_REPO_NAME in $(list); do
+			get_files
+		done | list_tracked_helper
+	fi
 }
 
-if [ "$1" = 'help' ] || [ "$#" -eq 0 ]; then
-	help
-	[ "$1" = 'help' ]
-	exit $?
+list_tracked_helper() {
+	sed "s,^,$(printf '%s\n' "$VCSH_BASE/" | sed 's/[,\&]/\\&/g')," | sort -u
+}
+
+list_tracked_by() {
+	list_tracked '' $2
+}
 
-elif [ "$1" = 'list' ]; then
-	verbose "list begin"
-	for i in "$VCSH_BASE"/*.git; do
-		echo $(basename "$i" .git)
+list_untracked() {
+	command -v 'comm' >/dev/null 2>&1 || fatal "Could not find 'comm'"
+
+	temp_file_others=$(mktemp "${TMPDIR:-/tmp}/tmp.XXXXXXXXXX") || fatal 'Could not create temp file'
+	temp_file_untracked=$(mktemp "${TMPDIR:-/tmp}/tmp.XXXXXXXXXX") || fatal 'Could not create temp file'
+	temp_file_untracked_copy=$(mktemp "${TMPDIR:-/tmp}/tmp.XXXXXXXXXX") || fatal 'Could not create temp file'
+
+	# Hack in support for `vcsh list-untracked -r`...
+	exclude_standard_opt='--exclude-standard'
+	directory_opt="--directory"
+	shift 1
+	while getopts "ar" flag; do
+		if [ x"$1" = x'-a' ]; then
+			unset exclude_standard_opt
+		elif [ x"$1" = x'-r' ]; then
+			unset directory_opt
+		fi
+		shift 1
 	done
-	verbose "list end"
-	exit 0
+	# ...and parse for a potential parameter afterwards. As we shifted things out of $* in during getops, we need to look at $1
+	VCSH_REPO_NAME=$1; export VCSH_REPO_NAME
 
-elif [ "$1" = 'run' ]; then
-	verbose "run begin"
-	use "$2"
-	shift 2
-	"$@"
-	leave
-	verbose "run end"
-	exit 0
-
-#elif [ "$1" = 'use' ]; then
-#	verbose "use begin"
-#	if [ -n "$ZSH_VERSION" ]; then
-#		if [ -o NO_IGNORE_EOF ]; then
-#			export VCSH_NO_IGNORE_EOF=1
-#			setopt IGNORE_EOF
-#		fi
-#		vcsh_exit() {
-#			vcsh exit;
-#			zle reset-prompt;
-#		}
-#		zle -N vcsh_exit
-#		bindkey '^d' 'vcsh_exit'
-#	fi
-#	use $2
-#	[ -n "$ZSH_VERSION" ] && [ "$USER" = richih ] && buildPS1
-#	verbose "use end"
-#	exit 0
-
-elif [ "$1" = 'clone' ]; then
-	verbose "clone begin"
-	GIT_REMOTE="$2"
-	REPO_NAME="$3"
-	[ -z "$REPO_NAME" ] && REPO_NAME=$(basename "$GIT_REMOTE" .git)
-	export REPO_NAME
-	export GIT_DIR="$VCSH_BASE/$REPO_NAME.git"
-	init
+	if [ -n "$VCSH_REPO_NAME" ]; then
+		list_untracked_helper $VCSH_REPO_NAME
+	else
+		for VCSH_REPO_NAME in $(list); do
+			list_untracked_helper $VCSH_REPO_NAME
+		done
+	fi
+	cat $temp_file_untracked
 
-	git remote add origin "$GIT_REMOTE"
-	git config branch.master.remote origin
-	git config branch.master.merge  refs/heads/master
-	git config core.excludesfile    ".gitignore.d/$REPO_NAME"
-	git fetch
-	for object in $(git ls-tree -r origin/master | awk '{print $4}'); do
-		[ -e "$object" ] &&
-			echo "$SELF: error: $object exists." &&
-			VCSH_CONFLICT=1;
+	unset directory_opt directory_component
+	rm -f $temp_file_others $temp_file_untracked $temp_file_untracked_copy || fatal 'Could not delete temp files'
+}
+
+list_untracked_helper() {
+	export GIT_DIR="$VCSH_REPO_D/$VCSH_REPO_NAME.git"
+	git ls-files --others $exclude_standard_opt "$directory_opt" | (
+		while read line; do
+			echo "$line"
+			directory_component=${line%%/*}
+			[ -d "$directory_component" ] && printf '%s/\n' "$directory_component"
+		done
+		) | sort -u > $temp_file_others
+	if [ -z "$ran_once" ]; then
+		ran_once=1
+		cp $temp_file_others $temp_file_untracked || fatal 'Could not copy temp file'
+	fi
+	cp $temp_file_untracked $temp_file_untracked_copy || fatal 'Could not copy temp file'
+	comm -12 $temp_file_others $temp_file_untracked_copy > $temp_file_untracked
+}
+
+pull() {
+	hook pre-pull
+	for VCSH_REPO_NAME in $(list); do
+		printf '%s: ' "$VCSH_REPO_NAME"
+		GIT_DIR=$VCSH_REPO_D/$VCSH_REPO_NAME.git; export GIT_DIR
+		use
+		git pull
+		VCSH_COMMAND_RETURN_CODE=$?
+		echo
 	done
-	[ "$VCSH_CONFLICT" = '1' ] &&
-		echo "$SELF: fatal: will stop after fetching and not try to merge!\n" &&
-		echo "  Once this situation has been resolved, run 'vcsh run <foo> git pull' to finish cloning.\n" &&
-		exit 3
-	git merge origin/master
-#	vcsh use $REPO_NAME
-	verbose "clone end"
-
-elif [ "$1" = 'init' ]; then
-	verbose "init begin"
-	[ -z $2 ] && help && echo && echo "$SELF $1: error: please specify repository to work on" && return 0
-	export REPO_NAME="$2"
-	export GIT_DIR="$VCSH_BASE/$REPO_NAME.git"
-	init
-#	vcsh use "$REPO_NAME"
-	verbose "init end"
-
-#elif [ "$1" = 'exit' ]; then
-#	verbose "exit begin"
-#	if [ -n "$ZSH_VERSION" ] && [ "$VCSH_NO_IGNORE_EOF" = '1' ]; then
-#		unset VCSH_NO_IGNORE_EOF
-#		setopt NO_IGNORE_EOF
-#	fi
-#	leave
-#	[ -n "$ZSH_VERSION" ] && [ "$USER" = richih ] && buildPS1
-#	verbose "exit end"
-#	exit 0
-
-elif [ "$1" = 'seed-gitignore' ]; then
-	verbose "seed-gitignore begin"
-	[ -z $2 ] && help && echo && echo "$SELF $1: error: please specify repository to work on" && return 0
-	use "$2"
-	git config core.excludesfile ".gitignore.d/$REPO_NAME"
-	files=$(git ls-files)
+	hook post-pull
+}
+
+push() {
+	hook pre-push
+	for VCSH_REPO_NAME in $(list); do
+		printf '%s: ' "$VCSH_REPO_NAME"
+		GIT_DIR=$VCSH_REPO_D/$VCSH_REPO_NAME.git; export GIT_DIR
+		use
+		git push
+		VCSH_COMMAND_RETURN_CODE=$?
+		echo
+	done
+	hook post-push
+}
+
+retire() {
+	unset VCSH_DIRECTORY
+}
+
+rename() {
+	git_dir_exists
+	[ -d "$GIT_DIR_NEW" ] && fatal "'$GIT_DIR_NEW' exists" 54
+	mv -f "$GIT_DIR" "$GIT_DIR_NEW" || fatal "Could not mv '$GIT_DIR' '$GIT_DIR_NEW'" 52
+
+	# Now that the repository has been renamed, we need to fix up its configuration
+	# Overwrite old name..
+	GIT_DIR=$GIT_DIR_NEW
+	VCSH_REPO_NAME=$VCSH_REPO_NAME_NEW
+	# ..and clobber all old configuration
+	upgrade
+}
+
+run() {
+	hook pre-run
+	use
+	"$@"
+	VCSH_COMMAND_RETURN_CODE=$?
+	hook post-run
+}
+
+status() {
+	if [ -t 1 ]; then
+		COLORING="-c color.status=always"
+	fi
+	if [ -n "$VCSH_REPO_NAME" ]; then
+		status_helper $VCSH_REPO_NAME
+	else
+		for VCSH_REPO_NAME in $(list); do
+			STATUS=$(status_helper $VCSH_REPO_NAME "$COLORING")
+			[ -n "$STATUS" -o -z "$VCSH_STATUS_TERSE" ] && echo "$VCSH_REPO_NAME:"
+			[ -n "$STATUS" ]            && echo "$STATUS"
+			[ -z "$VCSH_STATUS_TERSE" ] && echo
+		done
+	fi
+}
+
+status_helper() {
+	GIT_DIR=$VCSH_REPO_D/$1.git; export GIT_DIR
+	VCSH_GIT_OPTIONS=$2
+	use
+	remote_tracking_branch=$(git rev-parse --abbrev-ref --symbolic-full-name @{u} 2> /dev/null) && {
+		commits_behind=$(git log ..${remote_tracking_branch} --oneline | wc -l)
+		commits_ahead=$(git log ${remote_tracking_branch}.. --oneline | wc -l)
+		[ ${commits_behind} -ne 0 ] && echo "Behind $remote_tracking_branch by $commits_behind commits"
+		[ ${commits_ahead} -ne 0 ] && echo "Ahead of $remote_tracking_branch by $commits_ahead commits"
+	}
+	git ${VCSH_GIT_OPTIONS} status --short --untracked-files='no'
+	VCSH_COMMAND_RETURN_CODE=$?
+}
+
+upgrade() {
+	hook pre-upgrade
+	# fake-bare repositories are not bare, actually. Set this to false
+	# because otherwise Git complains "fatal: core.bare and core.worktree
+	# do not make sense"
+	git config core.bare false
+	# core.worktree may be absolute or relative to $GIT_DIR, depending on
+	# user preference
+	if [ ! "x$VCSH_WORKTREE" = 'xabsolute' ]; then
+		git config core.worktree "$(cd "$GIT_DIR" && GIT_WORK_TREE=$VCSH_BASE git rev-parse --show-cdup)"
+	elif [ ! "x$VCSH_WORKTREE" = 'xrelative' ]; then
+		git config core.worktree "$VCSH_BASE"
+	fi
+	[ ! "x$VCSH_GITIGNORE" = 'xnone' ] && git config core.excludesfile ".gitignore.d/$VCSH_REPO_NAME"
+	[ ! "x$VCSH_GITATTRIBUTES" = 'xnone' ] && git config core.attributesfile ".gitattributes.d/$VCSH_REPO_NAME"
+	git config vcsh.vcsh 'true'
+	use
+	[ -e "$VCSH_BASE/.gitignore.d/$VCSH_REPO_NAME" ] && git add -f "$VCSH_BASE/.gitignore.d/$VCSH_REPO_NAME"
+	[ -e "$VCSH_BASE/.gitattributes.d/$VCSH_REPO_NAME" ] && git add -f "$VCSH_BASE/.gitattributes.d/$VCSH_REPO_NAME"
+	hook post-upgrade
+}
+
+use() {
+	git_dir_exists
+	VCSH_DIRECTORY=$VCSH_REPO_NAME; export VCSH_DIRECTORY
+}
+
+which() {
+	output=$(for VCSH_REPO_NAME in $(list); do
+		get_files | grep -- "$VCSH_COMMAND_PARAMETER" | sed "s/^/$VCSH_REPO_NAME: /"
+	done | sort -u)
+	if [ -z "$output" ]; then
+		fatal "'$VCSH_COMMAND_PARAMETER' does not exist" 1
+	else
+		echo "$output"
+	fi
+}
+
+write_gitignore() {
+	# Don't do anything if the user does not want to write gitignore
+	if [ "x$VCSH_GITIGNORE" = 'xnone' ]; then
+		info "Not writing gitignore as '\$VCSH_GITIGNORE' is set to 'none'"
+		exit
+	fi
+
+	use
+	cd "$VCSH_BASE" || fatal "could not enter '$VCSH_BASE'" 11
+	OLDIFS=$IFS
+	IFS=$(printf '\n\t')
 	gitignores=$(for file in $(git ls-files); do
 		while true; do
-			echo $file; new="${file%/*}"
-			[ "$file" = "$new" ] && break
-			file="$new"
+			echo "$file"; new=${file%/*}
+			[ x"$file" = x"$new" ] && break
+			file=$new
 		done;
-	done | sort -u | sed 's/^/!/')
-	[ -e .gitignore.d/$2 ] &&
-	echo "$SELF: info: .gitignore.d/$2 exists, moving it to .gitignore.d/$2.bak" &&
-	mv -f .gitignore.d/$2 .gitignore.d/$2.bak
-	echo '*' > .gitignore.d/$2
+	done | sort -u)
+
+	# Contrary to GNU mktemp, mktemp on BSD/OSX requires a template for temp files
+	# Using a template makes GNU mktemp default to $PWD and not #TMPDIR for tempfile location
+	# To make every OS happy, set full path explicitly
+	tempfile=$(mktemp "${TMPDIR:-/tmp}/tmp.XXXXXXXXXX") || fatal "could not create tempfile: '${tempfile}'" 51
+
+	echo '*' > "$tempfile" || fatal "could not write to '$tempfile'" 57
 	for gitignore in $gitignores; do
-		echo $gitignore >> .gitignore.d/$2
+		echo "$gitignore" | sed 's@^@!/@' >> "$tempfile" || fatal "could not write to '$tempfile'" 57
+		if [ "x$VCSH_GITIGNORE" = 'xrecursive' ] && [ -d "$gitignore" ]; then
+			{ echo "$gitignore/*" | sed 's@^@!/@' >> "$tempfile" || fatal "could not write to '$tempfile'" 57; }
+		fi
 	done
+	IFS=$OLDIFS
+	if diff -N "$tempfile" "$VCSH_BASE/.gitignore.d/$VCSH_REPO_NAME" > /dev/null; then
+		rm -f "$tempfile" || error "could not delete '$tempfile'"
+		exit
+	fi
+	if [ -e "$VCSH_BASE/.gitignore.d/$VCSH_REPO_NAME" ]; then
+		info "'$VCSH_BASE/.gitignore.d/$VCSH_REPO_NAME' differs from new data, moving it to '$VCSH_BASE/.gitignore.d/$VCSH_REPO_NAME.bak'"
+		mv -f "$VCSH_BASE/.gitignore.d/$VCSH_REPO_NAME" "$VCSH_BASE/.gitignore.d/$VCSH_REPO_NAME.bak" ||
+			fatal "could not move '$VCSH_BASE/.gitignore.d/$VCSH_REPO_NAME' to '$VCSH_BASE/.gitignore.d/$VCSH_REPO_NAME.bak'" 53
+	fi
+	mv -f "$tempfile" "$VCSH_BASE/.gitignore.d/$VCSH_REPO_NAME" ||
+		fatal "could not move '$tempfile' to '$VCSH_BASE/.gitignore.d/$VCSH_REPO_NAME'" 53
+}
+
+debug $(git version)
+
+if [ ! "x$VCSH_GITIGNORE" = 'xexact' ] && [ ! "x$VCSH_GITIGNORE" = 'xnone' ] && [ ! "x$VCSH_GITIGNORE" = 'xrecursive' ]; then
+	fatal "'\$VCSH_GITIGNORE' must equal 'exact', 'none', or 'recursive'" 1
+fi
+
+VCSH_COMMAND=$1; export VCSH_COMMAND
+
+case $VCSH_COMMAND in
+	clon|clo|cl) VCSH_COMMAND=clone;;
+	commi|comm|com|co) VCSH_COMMAND=commit;;
+	delet|dele|del|de) VCSH_COMMAND=delete;;
+	ente|ent|en) VCSH_COMMAND=enter;;
+	hel|he) VCSH_COMMAND=help;;
+	ini|in) VCSH_COMMAND=init;;
+	pul) VCSH_COMMAND=pull;;
+	pus) VCSH_COMMAND=push;;
+	renam|rena|ren|re) VCSH_COMMAND=rename;;
+	ru) VCSH_COMMAND=run;;
+	statu|stat|sta|st) VCSH_COMMAND=status;;
+	upgrad|upgra|upgr|up) VCSH_COMMAND=upgrade;;
+	versio|versi|vers|ver|ve) VCSH_COMMAND=version;;
+	which|whi|wh) VCSH_COMMAND=which;;
+	write|writ|wri|wr) VCSH_COMMAND=write-gitignore;;
+esac    
 
+if [ x"$VCSH_COMMAND" = x'clone' ]; then
+	VCSH_BRANCH=
+	if [ "$2" = -b ]; then
+		VCSH_BRANCH=$3
+		shift
+		shift
+	fi
+	[ -z "$2" ] && fatal "$VCSH_COMMAND: please specify a remote" 1
+	GIT_REMOTE="$2"
+	[ -n "$VCSH_BRANCH" ] || if [ "$3" = -b ]; then
+		VCSH_BRANCH=$4
+		shift
+		shift
+	fi
+	if [ -n "$3" ]; then
+		VCSH_REPO_NAME=$3
+		[ -z "$VCSH_BRANCH" ] && [ "$4" = -b ] && VCSH_BRANCH=$5
+	else
+		VCSH_REPO_NAME=$(basename "${GIT_REMOTE#*:}" .git)
+	fi
+	[ -z "$VCSH_REPO_NAME" ] && fatal "$VCSH_COMMAND: could not determine repository name" 1
+	export VCSH_REPO_NAME
+	[ -n "$VCSH_BRANCH" ] || VCSH_BRANCH=master
+	GIT_DIR=$VCSH_REPO_D/$VCSH_REPO_NAME.git; export GIT_DIR
+elif [ "$VCSH_COMMAND" = 'version' ]; then
+	echo "$SELF $VERSION"
+	git version
+	exit
+elif [ x"$VCSH_COMMAND" = x'which' ]; then
+	[ -z "$2" ] && fatal "$VCSH_COMMAND: please specify a filename" 1
+	[ -n "$3" ] && fatal "$VCSH_COMMAND: too many parameters" 1
+	VCSH_COMMAND_PARAMETER=$2; export VCSH_COMMAND_PARAMETER
+elif [ x"$VCSH_COMMAND" = x'delete' ]           ||
+     [ x"$VCSH_COMMAND" = x'enter' ]            ||
+     [ x"$VCSH_COMMAND" = x'init' ]             ||
+     [ x"$VCSH_COMMAND" = x'list-tracked-by' ]  ||
+     [ x"$VCSH_COMMAND" = x'rename' ]           ||
+     [ x"$VCSH_COMMAND" = x'run' ]              ||
+     [ x"$VCSH_COMMAND" = x'upgrade' ]          ||
+     [ x"$VCSH_COMMAND" = x'write-gitignore' ]; then
+	[ -z "$2" ]                                     && fatal "$VCSH_COMMAND: please specify repository to work on" 1
+	[ x"$VCSH_COMMAND" = x'rename' ] && [ -z "$3" ] && fatal "$VCSH_COMMAND: please specify a target name" 1
+	[ x"$VCSH_COMMAND" = x'run'    ] && [ -z "$3" ] && fatal "$VCSH_COMMAND: please specify a command" 1
+	VCSH_REPO_NAME=$2; export VCSH_REPO_NAME
+	GIT_DIR=$VCSH_REPO_D/$VCSH_REPO_NAME.git; export GIT_DIR
+	[ x"$VCSH_COMMAND" = x'rename' ] && { VCSH_REPO_NAME_NEW=$3; export VCSH_REPO_NAME_NEW;
+	                                      GIT_DIR_NEW=$VCSH_REPO_D/$VCSH_REPO_NAME_NEW.git; export GIT_DIR_NEW; }
+	[ x"$VCSH_COMMAND" = x'run' ]    && shift 2
+elif [ x"$VCSH_COMMAND" = x'foreach' ]; then
+	[ -z "$2" ] && fatal "$VCSH_COMMAND: please specify a command" 1
+	shift 1
+elif [ x"$VCSH_COMMAND" = x'commit' ] ||
+     [ x"$VCSH_COMMAND" = x'list'   ] ||
+     [ x"$VCSH_COMMAND" = x'list-tracked' ] ||
+     [ x"$VCSH_COMMAND" = x'list-untracked' ] ||
+     [ x"$VCSH_COMMAND" = x'pull'   ] ||
+     [ x"$VCSH_COMMAND" = x'push'   ]; then
+	:
+elif [ x"$VCSH_COMMAND" = x'status' ]; then
+	if [ x"$2" = x'--terse' ]; then
+		VCSH_STATUS_TERSE=1; export VCSH_STATUS_TERSE
+		shift
+	fi
+	VCSH_REPO_NAME=$2; export VCSH_REPO_NAME
+elif [ -n "$2" ]; then
+	VCSH_COMMAND='run'; export VCSH_COMMAND
+	VCSH_REPO_NAME=$1; export VCSH_REPO_NAME
+	GIT_DIR=$VCSH_REPO_D/$VCSH_REPO_NAME.git; export GIT_DIR
+	[ -d "$GIT_DIR" ] || { help; exit 1; }
+	shift 1
+	set -- "git" "$@"
+elif [ -n "$VCSH_COMMAND" ]; then
+	VCSH_COMMAND='enter'; export VCSH_COMMAND
+	VCSH_REPO_NAME=$1; export VCSH_REPO_NAME
+	GIT_DIR=$VCSH_REPO_D/$VCSH_REPO_NAME.git; export GIT_DIR
+	[ -d "$GIT_DIR" ] || { help; exit 1; }
 else
-	verbose "defaulting to calling help()"
-	help
-	exit 3
+	# $1 is empty, or 'help'
+	help && exit
+fi
 
+# Did we receive a directory instead of a name?
+# Mangle the input to fit normal operation.
+if echo "$VCSH_REPO_NAME" | grep -q '/'; then
+	GIT_DIR=$VCSH_REPO_NAME; export GIT_DIR
+	VCSH_REPO_NAME=$(basename "$VCSH_REPO_NAME" .git); export VCSH_REPO_NAME
 fi
 
+check_dir() {
+	check_directory="$1"
+	if [ ! -d "$check_directory" ]; then
+		if [ -e "$check_directory" ]; then
+			fatal "'$check_directory' exists but is not a directory" 13
+		else
+			verbose "attempting to create '$check_directory'"
+			mkdir -p "$check_directory" || fatal "could not create '$check_directory'" 50
+		fi
+	fi
+}
+
+check_dir "$VCSH_REPO_D"
+[ ! "x$VCSH_GITIGNORE" = 'xnone' ] && check_dir "$VCSH_BASE/.gitignore.d"
+[ ! "x$VCSH_GITATTRIBUTES" = 'xnone' ] && check_dir "$VCSH_BASE/.gitattributes.d"
+
+verbose "$VCSH_COMMAND begin"
+VCSH_COMMAND=$(echo "$VCSH_COMMAND" | sed 's/-/_/g'); export VCSH_COMMAND
+
+# Source repo-specific configuration file
+[ -r "$XDG_CONFIG_HOME/vcsh/config.d/$VCSH_REPO_NAME" ] && . "$XDG_CONFIG_HOME/vcsh/config.d/$VCSH_REPO_NAME"
+
+# source overlay functions
+for overlay in "$VCSH_OVERLAY_D/$VCSH_COMMAND"* "$VCSH_OVERLAY_D/$VCSH_REPO_NAME.$VCSH_COMMAND"*; do
+	[ -r "$overlay" ] || continue
+	info "sourcing '$overlay'"
+	. "$overlay"
+done
+
+hook pre-command
+$VCSH_COMMAND "$@"
+hook post-command
+verbose "$VCSH_COMMAND end, exiting"
+exit $VCSH_COMMAND_RETURN_CODE