#!/bin/sh

  #
  # This scripts adds local version information from the version
  # control systems git, mercurial (hg) and subversion (svn).
  #

  # If something goes wrong, send a mail the kernel build mailinglist
  # (see MAINTAINERS) and CC Nico Schottelius
  # <nico-linuxsetlocalversion -at- schottelius.org>.
  #

  #

  
  usage() {

  	echo "Usage: $0 [--save-scmversion] [srctree]" >&2

  	exit 1
  }

  scm_only=false
  srctree=.
  if test "$1" = "--save-scmversion"; then
  	scm_only=true
  	shift
  fi
  if test $# -gt 0; then
  	srctree=$1
  	shift
  fi
  if test $# -gt 0 -o ! -d "$srctree"; then
  	usage
  fi
  
  scm_version()
  {
  	local short
  	short=false
  
  	cd "$srctree"
  	if test -e .scmversion; then
  		cat .scmversion
  		return
  	fi
  	if test "$1" = "--short"; then
  		short=true
  	fi
  
  	# Check for git and a git repo.

  	if test -z "$(git rev-parse --show-cdup 2>/dev/null)" &&
  	   head=`git rev-parse --verify --short HEAD 2>/dev/null`; then

  
  		# If we are at a tagged commit (like "v2.6.30-rc6"), we ignore
  		# it, because this version is defined in the top level Makefile.
  		if [ -z "`git describe --exact-match 2>/dev/null`" ]; then
  
  			# If only the short version is requested, don't bother
  			# running further git commands
  			if $short; then
  				echo "+"
  				return
  			fi
  			# If we are past a tagged commit (like
  			# "v2.6.30-rc5-302-g72357d5"), we pretty print it.
  			if atag="`git describe 2>/dev/null`"; then
  				echo "$atag" | awk -F- '{printf("-%05d-%s", $(NF-1),$(NF))}'
  
  			# If we don't have a tag at all we print -g{commitish}.
  			else
  				printf '%s%s' -g $head
  			fi
  		fi
  
  		# Is this git on svn?
  		if git config --get svn-remote.svn.url >/dev/null; then
  			printf -- '-svn%s' "`git svn find-rev $head`"
  		fi

  		# Check for uncommitted changes

  		if git diff-index --name-only HEAD | grep -qv "^scripts/package"; then

  			printf '%s' -dirty
  		fi

  		# All done with git
  		return

  	fi

  	# Check for mercurial and a mercurial repo.
  	if test -d .hg && hgid=`hg id 2>/dev/null`; then
  		# Do we have an tagged version?  If so, latesttagdistance == 1
  		if [ "`hg log -r . --template '{latesttagdistance}'`" == "1" ]; then
  			id=`hg log -r . --template '{latesttag}'`
  			printf '%s%s' -hg "$id"
  		else
  			tag=`printf '%s' "$hgid" | cut -d' ' -f2`
  			if [ -z "$tag" -o "$tag" = tip ]; then
  				id=`printf '%s' "$hgid" | sed 's/[+ ].*//'`
  				printf '%s%s' -hg "$id"
  			fi
  		fi
  
  		# Are there uncommitted changes?
  		# These are represented by + after the changeset id.
  		case "$hgid" in
  			*+|*+\ *) printf '%s' -dirty ;;
  		esac
  
  		# All done with mercurial
  		return

  	fi

  	# Check for svn and a svn repo.

  	if rev=`LANG= LC_ALL= LC_MESSAGES=C svn info 2>/dev/null | grep '^Last Changed Rev'`; then

  		rev=`echo $rev | awk '{print $NF}'`
  		printf -- '-svn%s' "$rev"
  
  		# All done with svn
  		return
  	fi
  }
  
  collect_files()
  {
  	local file res
  
  	for file; do
  		case "$file" in
  		*\~*)
  			continue
  			;;
  		esac
  		if test -e "$file"; then
  			res="$res$(cat "$file")"
  		fi
  	done
  	echo "$res"
  }
  
  if $scm_only; then
  	if test ! -e .scmversion; then
  		res=$(scm_version)
  		echo "$res" >.scmversion

  	fi

  	exit

  fi

  if test -e include/config/auto.conf; then

  	# We are interested only in CONFIG_LOCALVERSION and
          # CONFIG_LOCALVERSION_AUTO, so extract these in a safe
          # way (i.e. w/o sourcing auto.conf)
  	CONFIG_LOCALVERSION=`cat include/config/auto.conf | awk -F '=' '/^CONFIG_LOCALVERSION=/ {print $2}'`
  	CONFIG_LOCALVERSION_AUTO=`cat include/config/auto.conf | awk -F '=' '/^CONFIG_LOCALVERSION_AUTO=/ {print $2}'`

  else
  	echo "Error: kernelrelease not valid - run 'make prepare' to update it"
  	exit 1
  fi

  
  # localversion* files in the build and source directory
  res="$(collect_files localversion*)"
  if test ! "$srctree" -ef .; then
  	res="$res$(collect_files "$srctree"/localversion*)"
  fi
  
  # CONFIG_LOCALVERSION and LOCALVERSION (if set)
  res="${res}${CONFIG_LOCALVERSION}${LOCALVERSION}"
  
  # scm version string if not at a tagged commit
  if test "$CONFIG_LOCALVERSION_AUTO" = "y"; then
  	# full scm version string
  	res="$res$(scm_version)"
  else
  	# append a plus sign if the repository is not in a clean
  	# annotated or signed tagged state (as git describe only
  	# looks at signed or annotated tags - git tag -a/-s) and
  	# LOCALVERSION= is not specified
  	if test "${LOCALVERSION+set}" != "set"; then
  		scm=$(scm_version --short)
  		res="$res${scm:++}"
  	fi

  fi

  echo "$res"