Improve getrevision.sh

 - remove bashism.
 - simplify some git-related code.
 - improved parameter and error handling.
 - additional -d/--date action which is similar to the timestamp action.
 - support for an optional path parameter.
 - there is only one sane time format.
 - and only one sane date format too.
 - use UTC dates and times only.
 - vastly improve git_url() to print the correct remote url and
   "nearest" branch.
 - remove username from repository URLs.
 - add "-dirty" to local revisions if there are uncommitted changes.
 - indicate in local revisions how many git-only commits were done
   since branching from upstream svn.
 - fix svn_revision() fallback to svn info and remove git-svn.
 - print leading r in script instead of hardcode it in the makefile;
   no more "0.9.7-runknown".
 - make retrieving the upstream revision work even in cloned git-svn
   repositories.
 - more abstractions and helper functions.
 - less fragmentation of actual functionality.

Corresponding to flashrom svn r1727.

Signed-off-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>
Acked-by: Stefan Tauner <stefan.tauner@alumni.tuwien.ac.at>

2 files changed, 203 insertions, 151 deletions

diff --git a/Makefile b/Makefile
index 5410a71..f34ed1d 100644
--- a/Makefile
+++ b/Makefile
@@ -333,14 +333,13 @@ LIB_OBJS = layout.o flashrom.o udelay.o programmer.o
 
 CLI_OBJS = cli_classic.o cli_output.o print.o
 
-# Set the flashrom version string from the highest revision number
-# of the checked out flashrom files.
+# Set the flashrom version string from the highest revision number of the checked out flashrom files.
 # Note to packagers: Any tree exported with "make export" or "make tarball"
 # will not require subversion. The downloadable snapshots are already exported.
 SVNVERSION := $(shell ./util/getrevision.sh -u)
 
 RELEASE := 0.9.7
-VERSION := $(RELEASE)-r$(SVNVERSION)
+VERSION := $(RELEASE)-$(SVNVERSION)
 RELEASENAME ?= $(VERSION)
 
 SVNDEF := -D'FLASHROM_VERSION="$(VERSION)"'
diff --git a/util/getrevision.sh b/util/getrevision.sh
index 098f63e..c05f59e 100755
--- a/util/getrevision.sh
+++ b/util/getrevision.sh
@@ -1,10 +1,11 @@
-#!/bin/bash
+#!/bin/sh
 #
 # This file is part of the flashrom project.
 #
 # Copyright (C) 2005 coresystems GmbH <stepan@coresystems.de>
 # Copyright (C) 2009,2010 Carl-Daniel Hailfinger
 # Copyright (C) 2010 Chromium OS Authors
+# Copyright (C) 2013 Stefan Tauner
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -26,205 +27,257 @@ EXIT_FAILURE=1
 
 # Make sure we don't get translated output
 export LC_ALL=C
+# nor local times or dates
+export TZ=UTC0
 
-svn_revision() {
-	svnversion -cn . 2>/dev/null | \
-		sed -e "s/.*://" -e "s/\([0-9]*\).*/\1/" | \
-		grep "[0-9]" ||
-	svn info . 2>/dev/null | \
-		awk '/^Revision:/ {print $$2 }' | \
-		grep "[0-9]" ||
-	git svn info . 2>/dev/null | \
-		awk '/^Revision:/ {print $$2 }' | \
-		grep "[0-9]" ||
-	echo ''
+# Helper functions
+# First argument is the path to inspect (usually optional; w/o it the whole repository will be considered)
+svn_has_local_changes() {
+	svn status "$1" | egrep '^ *[ADMR] *' >/dev/null
 }
 
-svn_url() {
-	echo $(svn info 2>/dev/null |
-	       grep URL: |
-		   sed 's/.*URL:[[:blank:]]*//' |
-		   grep ^.
-	      )
+git_has_local_changes() {
+	git update-index -q --refresh >/dev/null
+	! git diff-index --quiet HEAD -- "$1"
 }
 
-svn_timestamp() {
-	local date_format="+%Y-%m-%d %H:%M:%S"
-	local timestamp
-
-	# are there local changes in the client?
-	if svn status | egrep '^ *[ADMR] *' > /dev/null ; then
-		timestamp=$(date "${date_format} +")
-	else
-		# No local changes, get date of the last log record.
-		local last_commit_date=$(svn info | grep '^Last Changed Date:' | awk '{print $4" "$5" "$6}')
-		timestamp=$(date --utc --date "${last_commit_date}" \
-			        "${date_format} UTC")
-	fi
-
-	echo "${timestamp}"
+git_last_commit() {
+	git log --pretty=format:"%h" -1 -- "$1"
 }
 
-git_revision() {
-	echo $(git log --oneline | head -1 | awk '{print $1}')
+svn_is_file_tracked() {
+	svn info "$1" >/dev/null 2>&1
 }
 
-# Retrieve svn revision using git log data (for git mirrors)
-gitsvn_revision() {
-	local r
-
-	git log|
-		grep git-svn-id|
-		sed 's/.*git-svn-id:[[:blank:]]*\([^@]\+\)@[0-9]\+[[:blank:]]\+\([^[:blank:]]\+\)/\1 \2/'|
-		sort|
-		uniq|
-		read url uuid
-
-	r=$(git log --grep="git-svn-id.*$uuid"| grep git-svn-id | \
-		sed 's/.*@//;s/[[:blank:]].*//'| \
-		sort -n | \
-		tail -1)
-
-	echo "${r}"
+git_is_file_tracked() {
+	git ls-files --error-unmatch -- "$1" >/dev/null 2>&1
 }
 
-git_timestamp() {
-	local date_format="+%b %d %Y %H:%M:%S"
-	local timestamp
-
-	# are there local changes in the client?
-	if git status | \
-	   egrep '^# Change(s to be committed|d but not updated):$' > /dev/null
-	then
-		timestamp=$(date "${date_format} +")
-	else
-		# No local changes, get date of the last log record.
-		local last_commit_date=$(git log | head -3 | grep '^Date:' | \
-		                         awk '{print $3" "$4" "$6" "$5" "$7}')
-		timestamp=$(date --utc --date "${last_commit_date}" \
-		            "${date_format} UTC")
-	fi
-
-	echo "${timestamp}"
+is_file_tracked() {
+	svn_is_file_tracked "$1" || git_is_file_tracked "$1"
 }
 
+# Tries to find a remote source for the changes committed locally.
+# This includes the URL of the remote repository including the last commit and a suitable branch name.
+# Takes one optional argument: the path to inspect
 git_url() {
-	# Only the first line of `git remote' is considered.
-	echo $(git remote show origin 2>/dev/null |
-	       grep 'Fetch URL:' |
-	       sed 's/.*URL:[[:blank:]]*//' |
-	       grep ^.
-	      )
+	last_commit=$(git_last_commit "$1")
+	# get all remote branches containing the last commit (excluding origin/HEAD and git-svn branches/tags)
+	branches=$(git branch -r --contains $last_commit | sed '/\//!d;/.*->.*/d;s/[\t ]*//')
+	if [ -z "$branches" ] ; then
+		echo "No remote branch contains a suitable commit">&2
+		return
+	fi
+
+	# find "nearest" branch
+	local mindiff=9000
+	local target=
+	for branch in $branches ; do
+		curdiff=$(git rev-list --count $last_commit..$branch)
+		if [ $curdiff -ge $mindiff ] ; then
+			continue
+		fi
+		mindiff=$curdiff
+		target=$branch
+	done
+
+	echo "$(git ls-remote --exit-code --get-url ${target%/*}) ${target#*/}"
 }
 
+# Returns a string indicating where others can get the current source code (excluding uncommitted changes)
+# Takes one optional argument: the path to inspect
 scm_url() {
-	local url
-
-	if [ -d ".svn" ] ; then
-		url=$(svn_url)
-	elif [ -d ".git" ] ; then
-		url=$(git_url)
+	local url=
+
+	# for a primitive VCS like subversion finding the URL is easy: there is only one upstream host
+	if svn_is_file_tracked "$1" ; then
+		url="$(svn info "$1" 2>/dev/null |
+		       grep URL: |
+		       sed 's/.*URL:[[:blank:]]*//;s/:\/\/.*@/:\/\//' |
+		       grep ^.)"
+	elif git_is_file_tracked "$1" ; then
+		url="$(git_url "$1")"
+	else
+		return ${EXIT_FAILURE}
 	fi
 
 	echo "${url}"
 }
 
 # Retrieve timestamp since last modification. If the sources are pristine,
-# then the timestamp will match that of the SCM's more recent modification
+# then the timestamp will match that of the SCM's most recent modification
 # date.
 timestamp() {
 	local t
 
-	if [ -d ".svn" ] ; then
-		t=$(svn_timestamp)
-	elif [ -d ".git" ] ; then
-		t=$(git_timestamp)
+	if svn_is_file_tracked "$2" ; then
+		if svn_has_local_changes "$2"; then
+			t=$(date -u "$1")
+		else
+			# No local changes, get date of the last log record.
+			local last_commit_date="$(svn info "$2" | \
+						  grep '^Last Changed Date:' | \
+						  awk '{print $4" "$5" "$6}')"
+			t=$(date -d "${last_commit_date}" -u "$1")
+		fi
+	elif git_is_file_tracked "$2" ; then
+		# are there local changes?
+		if git_has_local_changes "$2" ; then
+			t=$(date -u "${1}")
+		else
+			# No local changes, get date of the last commit
+			t=$(date -d "$(git log --pretty=format:"%cD" -1 -- "$2")" -u "$1")
+		fi
+	else
+		t=$(date -u "$1")
 	fi
 
-	echo ${t}
+	echo "${t}"
 }
 
-# Retrieve local SCM revision info. This is useful if we're working in
-# a even different SCM than upstream.
-#
-# If local copy is svn, then there is nothing to do here.
-# If local copy is git, then retrieve useful git revision info
+# Retrieve local SCM revision info. This is useful if we're working in a different SCM than upstream and/or
+# have local changes.
 local_revision() {
-	local r
-
-	if [ -d ".git" ] ; then
-		r=$(git_revision)
+	local r=
+
+	if svn_is_file_tracked "$1" ; then
+		r=$(svn_has_local_changes "$1" && echo "dirty")
+	elif git_is_file_tracked "$1" ; then
+		r=$(git_last_commit "$1")
+
+		local svn_base=$(git log --grep git-svn-id -1 --format='%h')
+		if [ "$svn_base" != "" ] ; then
+			local diff_to_svn=$(git rev-list --count ${svn_base}..${r})
+			if [ "$diff_to_svn" -gt 0 ] ; then
+				r="$r-$diff_to_svn"
+			fi
+		fi
+
+		if git_has_local_changes "$1" ; then
+			r="$r-dirty"
+		fi
+	else
+		return ${EXIT_FAILURE}
 	fi
 
-	echo ${r}
+	echo "${r}"
 }
 
 # Get the upstream flashrom revision stored in SVN metadata.
-#
-# If the local copy is svn, then use svnversion
-# If the local copy is git, then scrape upstream revision from git logs
 upstream_revision() {
-	local r
-
-	if [ -d ".svn" ] ; then
-		r=$(svn_revision)
-	elif [ -d ".git" ] ; then
-		r=$(gitsvn_revision)
+	local r=
+
+	if svn_is_file_tracked "$1" ; then
+		r=$(svn info "$1" 2>/dev/null | \
+		    grep "Last Changed Rev:" | \
+		    sed -e "s/^Last Changed Rev: *//" -e "s/\([0-9]*\).*/r\1/" | \
+		    grep "r[0-9]")
+	elif git_is_file_tracked "$1" ; then
+		# If this is a "native" git-svn clone we could use git svn log:
+		# git svn log --oneline -1 | sed 's/^r//;s/[[:blank:]].*//' or even git svn find-rev
+		# but it is easier to just grep for the git-svn-id unconditionally
+		r=$(git log --grep git-svn-id -1 -- "$1" | \
+		    grep git-svn-id | \
+		    sed 's/.*@/r/;s/[[:blank:]].*//')
 	fi
 
+	if [ -z "$r" ]; then
+		r="unknown" # default to unknown
+	fi
 	echo "${r}"
 }
 
 show_help() {
 	echo "Usage:
-	${0} <option>
+	${0} <command> [path]
 
-Options
+Commands
     -h or --help
-        Display this message.
-    -u or --upstream
-        upstream flashrom revision
+        this message
     -l or --local
-        local revision (if different from upstream)
+        local revision information including an indicator for uncommitted changes
+    -u or --upstream
+        upstream revision
+    -U or --url
+        URL associated with the latest commit
+    -d or --date
+        date of most recent modification
     -t or --timestamp
         timestamp of most recent modification
-    -U or --url
-        url associated with local copy of flashrom
-	"
+"
 	return
 }
 
-if [ ! -n "${1}" ]
-then
-	show_help;
-	echo "No options specified";
-	exit ${EXIT_SUCCESS}
-fi
-
-# The is the main loop
-while [[ ${1} = -* ]];
-do
-	case ${1} in
-	-h|--help)
-		show_help;
-		shift;;
-	-u|--upstream)
-		echo "$(upstream_revision)";
-		shift;;
-	-l|--local)
-		echo "$(local_revision)";
-		shift;;
-	-t|--timestamp)
-		echo "$(timestamp)";
-		shift;;
-	-U|--url)
-		echo "$(scm_url)";
-		shift;;
-	*)
-		show_help;
-		echo "invalid option: ${1}"
+check_action() {
+	if [ -n "$action" ]; then
+		echo "Error: Multiple actions given.">&2
 		exit ${EXIT_FAILURE}
-	esac;
-done
+	fi
+}
+
+main() {
+	local query_path=
+	local action=
+
+	# The is the main loop
+	while [ $# -gt 0 ];
+	do
+		case ${1} in
+		-h|--help)
+			action=show_help;
+			shift;;
+		-l|--local)
+			check_action $1
+			action=local_revision
+			shift;;
+		-u|--upstream)
+			check_action $1
+			action=upstream_revision
+			shift;;
+		-U|--url)
+			check_action $1
+			action=scm_url
+			shift;;
+		-d|--date)
+			check_action $1
+			action="timestamp +%Y-%m-%d" # refrain from suffixing 'Z' to indicate it's UTC
+			shift;;
+		-t|--timestamp)
+			check_action $1
+			action="timestamp +%Y-%m-%dT%H:%M:%SZ" # There is only one valid time format! ISO 8601
+			shift;;
+		-*)
+			show_help;
+			echo "Error: Invalid option: ${1}"
+			exit ${EXIT_FAILURE};;
+		*)
+			if [ -z "$query_path" ] ; then
+				if [ ! -e "$1" ] ; then
+					echo "Error: Path \"${1}\" does not exist.">&2
+					exit ${EXIT_FAILURE}
+				fi
+				query_path=$1
+			else
+				echo "Warning: Ignoring over-abundant paramter: \"${1}\"">&2
+			fi
+			shift;;
+		esac;
+	done
+
+	# default to current directory (usually equals the whole repository)
+	if [ -z "$query_path" ] ; then
+		query_path=.
+	fi
+	if ! is_file_tracked "$query_path" ; then
+		echo "Warning: Path \"${query_path}\" is not under version control.">&2
+	fi
+	if [ -z "$action" ] ; then
+		show_help
+		echo "Error: No actions specified"
+		exit ${EXIT_FAILURE}
+	fi
+
+	$action "$query_path"
+}
 
-exit ${EXIT_SUCCESS}
+main $@