#!/bin/sh
#
# Copyright (c) 2005, Linus Torvalds
# Copyright (c) 2005, Junio C Hamano
#
# Clone a repository into a different directory that does not yet exist.

# See git-sh-setup why.
unset CDPATH

setglobal OPTIONS_SPEC = '"\
git-clone [options] [--] <repo> [<dir>]
--
n,no-checkout        don't create a checkout
bare                 create a bare repository
naked                create a bare repository
l,local              to clone from a local repository
no-hardlinks         don't use local hardlinks, always copy
s,shared             setup as a shared repository
template=            path to the template directory
q,quiet              be quiet
reference=           reference repository
o,origin=            use <name> instead of 'origin' to track upstream
u,upload-pack=       path to git-upload-pack on the remote
depth=               create a shallow clone of that depth

use-separate-remote  compatibility, do not use
no-separate-remote   compatibility, do not use'"

proc die {
	echo >&2 @Argv> !2 "$@"
	exit 1
}

proc usage {
	exec $0 -h
}

eval $[echo $OPTIONS_SPEC | git rev-parse --parseopt -- @Argv || echo exit $Status]

proc get_repo_base {
	shell {
		cd $[/bin/pwd] &&
		cd $1 || cd "$1.git" &&
		do {
			cd .git
			pwd
		}
	} 2>/dev/null
}

if test -n $GIT_SSL_NO_VERIFY -o \
	$[git config --bool http.sslVerify] = false {
    setglobal curl_extra_args = '"-k'"
}

proc http_fetch {
	# $1 = Remote, $2 = Local
	curl -nsfL $curl_extra_args $1 >$2
	setglobal curl_exit_status = $Status
	match $curl_exit_status {
	with 126|127 exit 
	with *	 return $curl_exit_status 
	}
}

proc clone_dumb_http {
	# $1 - remote, $2 - local
	cd $2 &&
	setglobal clone_tmp = ""$GIT_DIR/clone-tmp"" &&
	mkdir -p $clone_tmp || exit 1
	if test -n $GIT_CURL_FTP_NO_EPSV -o \
		$[git config --bool http.noEPSV] = true {
		setglobal curl_extra_args = ""$(curl_extra_args) --disable-epsv""
	}
	http_fetch "$1/info/refs" "$clone_tmp/refs" ||
		die "Cannot get remote repository information.
Perhaps git-update-server-info needs to be run there?"
	test "z$quiet" = z && setglobal v = '-v' || setglobal v = ''
	while read sha1 refname
	{
		setglobal name = $[expr "z$refname" : 'zrefs/\(.*\)] &&
		match $name {
		with *^*	continue
		}
		match "$bare,$name" {
		with yes,* | ,heads/* | ,tags/* 
		with *	continue 
		}
		if test -n $use_separate_remote &&
		   setglobal branch_name = $[expr "z$name" : 'zheads/\(.*\)]
		{
			setglobal tname = ""remotes/$origin/$branch_name""
		} else {
			setglobal tname = $name
		}
		git-http-fetch $v -a -w $tname $sha1 $1 || exit 1
	} <"$clone_tmp/refs"
	rm -fr $clone_tmp
	http_fetch "$1/HEAD" "$GIT_DIR/REMOTE_HEAD" ||
	rm -f "$GIT_DIR/REMOTE_HEAD"
	if test -f "$GIT_DIR/REMOTE_HEAD" {
		setglobal head_sha1 = $[cat "$GIT_DIR/REMOTE_HEAD]
		match $head_sha1 {
		with 'ref: refs/'*
			
		with *
			git-http-fetch $v -a $head_sha1 $1 ||
			rm -f "$GIT_DIR/REMOTE_HEAD"
			
		}
	}
}

setglobal quiet = ''
setglobal local = 'no'
setglobal use_local_hardlink = 'yes'
setglobal local_shared = 'no'
unset template
setglobal no_checkout = ''
setglobal upload_pack = ''
setglobal bare = ''
setglobal reference = ''
setglobal origin = ''
setglobal origin_override = ''
setglobal use_separate_remote = 't'
setglobal depth = ''
setglobal no_progress = ''
setglobal local_explicitly_asked_for = ''
test -t 1 || setglobal no_progress = '--no-progress'

while test $# != 0
{
	match $1 {
	with -n|--no-checkout
		setglobal no_checkout = 'yes' 
	with --naked|--bare
		setglobal bare = 'yes' 
	with -l|--local
		setglobal local_explicitly_asked_for = 'yes'
		setglobal use_local_hardlink = 'yes'
		
	with --no-hardlinks
		setglobal use_local_hardlink = 'no' 
	with -s|--shared
		setglobal local_shared = 'yes' 
	with --template
		shift; setglobal template = ""--template=$1"" 
	with -q|--quiet
		setglobal quiet = '-q' 
	with --use-separate-remote|--no-separate-remote
		die "clones are always made with separate-remote layout" 
	with --reference
		shift; setglobal reference = $1 
	with -o|--origin
		shift;
		match $1 {
		with ''
		    usage 
		with */*
		    die "'$1' is not suitable for an origin name"
		}
		git check-ref-format "heads/$1" ||
		    die "'$1' is not suitable for a branch name"
		test -z $origin_override ||
		    die "Do not give more than one --origin options."
		setglobal origin_override = 'yes'
		setglobal origin = $1
		
	with -u|--upload-pack
		shift
		setglobal upload_pack = ""--upload-pack=$1"" 
	with --depth
		shift
		setglobal depth = ""--depth=$1"" 
	with --
		shift
		break 
	with *
		usage 
	}
	shift
}

setglobal repo = $1
test -n $repo ||
    die 'you must specify a repository to clone.'

# --bare implies --no-checkout and --no-separate-remote
if test yes = $bare
{
	if test yes = $origin_override
	{
		die '--bare and --origin $origin options are incompatible.'
	}
	setglobal no_checkout = 'yes'
	setglobal use_separate_remote = ''
}

if test -z $origin
{
	setglobal origin = 'origin'
}

# Turn the source into an absolute path if
# it is local
if setglobal base = $[get_repo_base $repo] {
	setglobal repo = $base
	if test -z $depth
	{
		setglobal local = 'yes'
	}
} elif test -f $repo
{
	match $repo { with /*  with * setglobal repo = ""$PWD/$repo""  }
}

# Decide the directory name of the new repository
if test -n $2
{
	setglobal dir = $2
	test $Argc = 2 || die "excess parameter to git-clone"
} else {
	# Derive one from the repository name
	# Try using "humanish" part of source repo if user didn't specify one
	if test -f $repo
	{
		# Cloning from a bundle
		setglobal dir = $[echo $repo | sed -e 's|/*\.bundle$||' -e 's|.*/||g]
	} else {
		setglobal dir = $[echo $repo |
			sed -e 's|/$||' -e 's|:*/*\.git$||' -e 's|.*[/:]||g]
	}
}

test -e $dir && die "destination directory '$dir' already exists."
test yes = $bare && unset GIT_WORK_TREE
test -n $GIT_WORK_TREE && test -e $GIT_WORK_TREE &&
die "working tree '$GIT_WORK_TREE' already exists."
setglobal D = ''
setglobal W = ''
proc cleanup {
	test -z $D && rm -rf $dir
	test -z $W && test -n $GIT_WORK_TREE && rm -rf $GIT_WORK_TREE
	cd ..
	test -n $D && rm -rf $D
	test -n $W && rm -rf $W
	exit $err
}
trap 'err=$?; cleanup' 0
mkdir -p $dir && setglobal D = $[cd $dir && pwd] || usage
test -n $GIT_WORK_TREE && mkdir -p $GIT_WORK_TREE &&
setglobal W = $[cd $GIT_WORK_TREE && pwd] && setglobal GIT_WORK_TREE = $W && export GIT_WORK_TREE
if test yes = $bare || test -n $GIT_WORK_TREE {
	setglobal GIT_DIR = $D
} else {
	setglobal GIT_DIR = ""$D/.git""
} &&
export GIT_DIR &&
env GIT_CONFIG="$GIT_DIR/config" git-init $quiet $(template+"$template") || usage

if test -n $bare
{
	env GIT_CONFIG="$GIT_DIR/config" git config core.bare true
}

if test -n $reference
{
	setglobal ref_git = ''
	if test -d $reference
	{
		if test -d "$reference/.git/objects"
		{
			setglobal ref_git = ""$reference/.git""
		} elif test -d "$reference/objects"
		{
			setglobal ref_git = $reference
		}
	}
	if test -n $ref_git
	{
		setglobal ref_git = $[cd $ref_git && pwd]
		echo "$ref_git/objects" >"$GIT_DIR/objects/info/alternates"
		shell {
			env GIT_DIR=$ref_git git for-each-ref \
				--format='%(objectname) %(*objectname)'
		} |
		while read a b
		{
			test -z $a ||
			git update-ref "refs/reference-tmp/$a" $a
			test -z $b ||
			git update-ref "refs/reference-tmp/$b" $b
		}
	} else {
		die "reference repository '$reference' is not a local directory."
	}
}

rm -f "$GIT_DIR/CLONE_HEAD"

# We do local magic only when the user tells us to.
match $local {
with yes
	shell { cd "$repo/objects" } ||
		die "cannot chdir to local '$repo/objects'."

	if test $local_shared = yes
	{
		mkdir -p "$GIT_DIR/objects/info"
		echo "$repo/objects" >>"$GIT_DIR/objects/info/alternates"
	} else {
		setglobal cpio_quiet_flag = ''""
		cpio --help !2 > !1 | grep -- --quiet >/dev/null && \
			setglobal cpio_quiet_flag = '--quiet'
		setglobal l = '' &&
		if test $use_local_hardlink = yes
		{
			# See if we can hardlink and drop "l" if not.
			setglobal sample_file = $[cd $repo && \
				      find objects -type f -print | sed -e 1q]
			# objects directory should not be empty because
			# we are cloning!
			test -f "$repo/$sample_file" ||
				die "fatal: cannot clone empty repository"
			if ln "$repo/$sample_file" "$GIT_DIR/objects/sample" !2 >/dev/null
			{
				rm -f "$GIT_DIR/objects/sample"
				setglobal l = 'l'
			} elif test -n $local_explicitly_asked_for
			{
				echo >&2 "Warning: -l asked but cannot hardlink to $repo> !2 "Warning: -l asked but cannot hardlink to $repo"
			}
		} &&
		cd $repo &&
		# Create dirs using umask and permissions and destination
		find objects -type d -print | shell {cd $GIT_DIR && xargs mkdir -p} &&
		# Copy existing 0444 permissions on content
		find objects ! -type d -print | cpio $cpio_quiet_flag -pumd$l "$GIT_DIR/" || \
			exit 1
	}
	git-ls-remote $repo >"$GIT_DIR/CLONE_HEAD" || exit 1
	
with *
	match $repo {
	with rsync://*
		match $depth {
		with "" 
		with * die "shallow over rsync not supported" 
		}
		rsync $quiet -av --ignore-existing  \
			--exclude info "$repo/objects/" "$GIT_DIR/objects/" ||
		exit
		# Look at objects/info/alternates for rsync -- http will
		# support it natively and git native ones will do it on the
		# remote end.  Not having that file is not a crime.
		rsync -q "$repo/objects/info/alternates" \
			"$GIT_DIR/TMP_ALT" !2 >/dev/null ||
			rm -f "$GIT_DIR/TMP_ALT"
		if test -f "$GIT_DIR/TMP_ALT"
		{
		    shell { cd $D &&
		      source git-parse-remote &&
		      resolve_alternates $repo <"$GIT_DIR/TMP_ALT" } |
		    while read alt
		    {
			match $alt { with 'bad alternate: '* die $alt }
			match $quiet {
			with ''	echo >&2 "Getting alternate: $alt> !2 "Getting alternate: $alt" 
			}
			rsync $quiet -av --ignore-existing  \
			    --exclude info $alt "$GIT_DIR/objects" || exit
		    }
		    rm -f "$GIT_DIR/TMP_ALT"
		}
		git-ls-remote $repo >"$GIT_DIR/CLONE_HEAD" || exit 1
		
	with https://*|http://*|ftp://*
		match $depth {
		with "" 
		with * die "shallow over http or ftp not supported" 
		}
		if test -z "@@NO_CURL@@"
		{
			clone_dumb_http $repo $D
		} else {
			die "http transport not supported, rebuild Git with curl support"
		}
		
	with *
		if test -f $repo  {
			git bundle unbundle $repo > "$GIT_DIR/CLONE_HEAD" ||
			die "unbundle from '$repo' failed."
		} else {
			match $upload_pack {
			with '' git-fetch-pack --all -k $quiet $depth $no_progress $repo
			with * git-fetch-pack --all -k \
				$quiet $upload_pack $depth $no_progress $repo 
			} >"$GIT_DIR/CLONE_HEAD" ||
			die "fetch-pack from '$repo' failed."
		}
		
	}
	
}
test -d "$GIT_DIR/refs/reference-tmp" && rm -fr "$GIT_DIR/refs/reference-tmp"

if test -f "$GIT_DIR/CLONE_HEAD"
{
	# Read git-fetch-pack -k output and store the remote branches.
	if test -n $use_separate_remote
	{
		setglobal branch_top = ""remotes/$origin""
	} else {
		setglobal branch_top = '"heads'"
	}
	setglobal tag_top = '"tags'"
	while read sha1 name
	{
		match $name {
		with *'^{}'
			continue 
		with HEAD
			setglobal destname = '"REMOTE_HEAD'" 
		with refs/heads/*
			setglobal destname = ""refs/$branch_top/$(name#refs/heads/)"" 
		with refs/tags/*
			setglobal destname = ""refs/$tag_top/$(name#refs/tags/)"" 
		with *
			continue 
		}
		git update-ref -m "clone: from $repo" $destname $sha1 ""
	} < "$GIT_DIR/CLONE_HEAD"
}

if test -n $W {
	cd $W || exit
} else {
	cd $D || exit
}

if test -z $bare
{
	# a non-bare repository is always in separate-remote layout
	setglobal remote_top = ""refs/remotes/$origin""
	setglobal head_sha1 = ''
	test ! -r "$GIT_DIR/REMOTE_HEAD" || setglobal head_sha1 = $[cat "$GIT_DIR/REMOTE_HEAD]
	match $head_sha1 {
	with 'ref: refs/'*
		# Uh-oh, the remote told us (http transport done against
		# new style repository with a symref HEAD).
		# Ideally we should skip the guesswork but for now
		# opt for minimum change.
		setglobal head_sha1 = $[expr "z$head_sha1" : 'zref: refs/heads/\(.*\)]
		setglobal head_sha1 = $[cat "$GIT_DIR/$remote_top/$head_sha1]
		
	}

	# The name under $remote_top the remote HEAD seems to point at.
	setglobal head_points_at = $[
		shell {
			test -f "$GIT_DIR/$remote_top/master" && echo "master"
			cd "$GIT_DIR/$remote_top" &&
			find . -type f -print | sed -e 's/^\.\///'
		} | shell {
		setglobal done = 'f'
		while read name
		{
			test t = $done && continue
			setglobal branch_tip = $[cat "$GIT_DIR/$remote_top/$name]
			if test $head_sha1 = $branch_tip
			{
				echo $name
				setglobal done = 't'
			}
		}
		}]

	# Upstream URL
	git config remote."$origin".url $repo &&

	# Set up the mappings to track the remote branches.
	git config remote."$origin".fetch \
		"+refs/heads/*:$remote_top/*" '^$' &&

	# Write out remote.$origin config, and update our "$head_points_at".
	match $head_points_at {
	with ?*
		# Local default branch
		git symbolic-ref HEAD "refs/heads/$head_points_at" &&

		# Tracking branch for the primary branch at the remote.
		git update-ref HEAD $head_sha1 &&

		rm -f "refs/remotes/$origin/HEAD"
		git symbolic-ref "refs/remotes/$origin/HEAD" \
			"refs/remotes/$origin/$head_points_at" &&

		git config branch."$head_points_at".remote $origin &&
		git config branch."$head_points_at".merge "refs/heads/$head_points_at"
		
	with ''
		if test -z $head_sha1
		{
			# Source had nonexistent ref in HEAD
			echo >&2 "Warning: Remote HEAD refers to nonexistent ref, unable to checkout.> !2 "Warning: Remote HEAD refers to nonexistent ref, unable to checkout."
			setglobal no_checkout = 't'
		} else {
			# Source had detached HEAD pointing nowhere
			git update-ref --no-deref HEAD $head_sha1 &&
			rm -f "refs/remotes/$origin/HEAD"
		}
		
	}

	match $no_checkout {
	with ''
		test "z$quiet" = z && test "z$no_progress" = z && setglobal v = '-v' || setglobal v = ''
		git read-tree -m -u $v HEAD HEAD
	}
}
rm -f "$GIT_DIR/CLONE_HEAD" "$GIT_DIR/REMOTE_HEAD"

trap - 0