#!/bin/sh

# RCS to ChangeLog generator

# Generate a change log prefix from RCS files and the ChangeLog (if any).
# Output the new prefix to standard output.
# You can edit this prefix by hand, and then prepend it to ChangeLog.

# Ignore log entries that start with `#'.
# Clump together log entries that start with `{topic} ',
# where `topic' contains neither white space nor `}'.

# Author: Paul Eggert <eggert@twinsun.com>

# $Id: rcs2log,v 1.15 1993/09/24 01:03:32 eggert Exp eggert $

# Copyright 1992, 1993 Free Software Foundation, Inc.

# 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
# the Free Software Foundation; either version 2, or (at your option)
# any later version.
# 
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
# 
# You should have received a copy of the GNU General Public License
# along with this program; see the file COPYING.  If not, write to
# the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.

nl='
'

# Parse options.

# defaults
: ${TMPDIR=/tmp}
hostname= # name of local host (if empty, will deduce it later)
indent=8 # indent of log line
initialize_fullname= # awk assignments to set up fullname array
initialize_mailaddr= # awk assignments to set up mailaddr array
length=79 # suggested max width of log line
logins= # login names for people we know fullnames and mailaddresses of
loginsout= # temporary file holding sorted logins
rlog_options= # options to pass to rlog
tabwidth=8 # width of horizontal tab

while :
do
	case $1 in
	-i)	indent=${2?};;
	-h)	hostname=${2?};;
	-l)	length=${2?};;
	-n)	logins=$logins$nl${2?}
		loginsout=$TMPDIR/rcs2log$$l
		case $2${3?}${4?} in
		*\"* | *\\* | *"$nl"*)
			echo >&2 "$0: -n '$2' '$3' '$4': special characters not allowed"
			exit 1
		esac
		initialize_fullname="$initialize_fullname
			fullname[\"$2\"] = \"$3\""
		initialize_mailaddr="$initialize_mailaddr
			mailaddr[\"$2\"] = \"$4\""
		shift; shift;;
	-r)	rlog_options=$rlog_options$nl${2?};;
	-t)	tabwidth=${2?};;
	-*)	echo >&2 "$0: usage: $0 [options] [file ...]
Options:
	[-h hostname] [-i indent] [-l length] [-n login fullname mailaddr]...
	[-r rlog_option]... [-t tabwidth]"
		exit 1;;
	*)	break
	esac
	shift; shift
done

month_data='
	m[0]="Jan"; m[1]="Feb"; m[2]="Mar"
	m[3]="Apr"; m[4]="May"; m[5]="Jun"
	m[6]="Jul"; m[7]="Aug"; m[8]="Sep"
	m[9]="Oct"; m[10]="Nov"; m[11]="Dec"

	# days in non-leap year thus far, indexed by month (0-12)
	mo[0]=0; mo[1]=31; mo[2]=59; mo[3]=90
	mo[4]=120; mo[5]=151; mo[6]=181; mo[7]=212
	mo[8]=243; mo[9]=273; mo[10]=304; mo[11]=334
	mo[12]=365
'


# Log into $rlogout the revisions checked in since the first ChangeLog entry.

date=1970
if test -s ChangeLog
then
	# Add 1 to seconds to avoid duplicating most recent log.
	e='
		/^... ... [ 0-9][0-9] [ 0-9][0-9]:[0-9][0-9]:[0-9][0-9] [0-9]+ /{
			'"$month_data"'
			year = $5
			for (i=0; i<=11; i++) if (m[i] == $2) break
			dd = $3
			hh = substr($0,12,2)
			mm = substr($0,15,2)
			ss = substr($0,18,2)
			ss++
			if (ss == 60) {
				ss = 0
				mm++
				if (mm == 60) {
					mm = 0
					hh++
					if (hh == 24) {
						hh = 0
						dd++
						monthdays = mo[i+1] - mo[i]
						if (i == 1 && year%4 == 0 && (year%100 != 0 || year%400 == 0)) monthdays++
						if (dd == monthdays + 1) {
							dd = 1
							i++
							if (i == 12) {
								i = 0
								year++
							}
						}
					}
				}
			}
			printf "%d/%02d/%02d %02d:%02d:%02d\n", year, i+1, dd, hh, mm, ss
			exit
		}
	'
	d=`awk "$e" <ChangeLog` || exit
	case $d in
	?*) date=$d
	esac
fi
datearg="-d>$date"

# With no arguments, examine all files under the RCS directory.
case $# in
0)
	files=
	for file in RCS/.* RCS/* .*,v *,v
	do
		case $file in
		RCS/. | RCS/..) continue;;
		RCS/.\* | RCS/\* | .\*,v | \*,v) test -f "$file" || continue
		esac
		files=$files$nl$file
	done
	case $files in
	'') exit 0
	esac
	oldIFS=$IFS
	IFS=$nl
	set $files
	IFS=$oldIFS
esac

rlogout=$TMPDIR/rcs2log$$r
trap exit 1 2 13 15
trap "rm -f $loginsout $rlogout; exit 1" 0

rlog "$datearg" $rlog_options "$@" >$rlogout || exit


# Get the full name of each author the logs mention, and set initialize_fullname
# to awk code that initializes the `fullname' awk associative array.
# Warning: foreign authors (i.e. not known in the passwd file) are mishandled;
# you have to fix the resulting output by hand.

case $loginsout in
?*) sort -u -o $loginsout <<EOF || exit
$logins
EOF
esac
authors=`
	sed -n 's|^date: *[0-9]*/[0-9][0-9]/[0-9][0-9] [0-9][0-9]:[0-9][0-9]:[0-9][0-9]; *author: *\([^; ]*\).*|\1|p' <$rlogout |
	case $loginsout in
	'') sort -u;;
	?*) sort -u | comm -23 - $loginsout
	esac
`
case $authors in
?*)
	initialize_author=
	for author in $authors
	do
		initialize_author="$initialize_author
			author[\"$author\"] = 1
		"
	done
	awkscript='
		BEGIN {
			alphabet = "abcdefghijklmnopqrstuvwxyz"
			ALPHABET = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
			'"$initialize_author"'
		}
		{
			if (author[$1]) {
				fullname = $5
				if (fullname ~ /[0-9]+-[^(]*\([0-9]+\)$/) {
					# Remove the junk from fullnames like "0000-Admin(0000)".
					fullname = substr(fullname, index(fullname, "-") + 1)
					fullname = substr(fullname, 1, index(fullname, "(") - 1)
				}
				if (fullname ~ /,[^ ]/) {
					# Some sites put comma-separated junk after the fullname.
					# Remove it, but leave "Bill Gates, Jr" alone.
					fullname = substr(fullname, 1, index(fullname, ",") - 1)
				}
				abbr = index(fullname, "&")
				if (abbr) {
					a = substr($1, 1, 1)
					A = a
					i = index(alphabet, a)
					if (i) A = substr(ALPHABET, i, 1)
					fullname = substr(fullname, 1, abbr-1) A substr($1, 2) substr(fullname, abbr+1)
				}
				printf "fullname[\"%s\"] = \"%s\"\n", $1, fullname
				author[$1] = 0
			}
		}
	'

	initialize_fullname=`
		(cat /etc/passwd; ypmatch $authors passwd) 2>/dev/null |
		awk -F: "$awkscript"
	`$initialize_fullname
esac


# Function to print a single log line.
# We don't use awk functions, to stay compatible with old awk versions.
# `Log' is the log message (with \n replaced by \r).
# `files' contains the affected files.
printlogline='{

	# Following the GNU coding standards, rewrite
	#	* file: (function): comment
	# to
	#	* file (function): comment
	if (Log ~ /^\([^)]*\): /) {
		i = index(Log, ")")
		files = files " " substr(Log, 1, i)
		Log = substr(Log, i+3)
	}

	# If "label: comment" is too long, break the line after the ":".
	sep = " "
	if ('"$length"' <= '"$indent"' + 1 + length(files) + index(Log, CR)) sep = "\n" indent_string

	# Print the label.
	printf "%s*%s:", indent_string, files

	# Print each line of the log, transliterating \r to \n.
	while ((i = index(Log, CR)) != 0) {
		logline = substr(Log, 1, i-1)
		if (logline ~ /[^	 ]/) {
			printf "%s%s\n", sep, logline
		} else {
			print ""
		}
		sep = indent_string
		Log = substr(Log, i+1)
	}
}'

case $hostname in
'')
	hostname=`(
		hostname || uname -n || uuname -l || cat /etc/whoami
	) 2>/dev/null` || {
		echo >&2 "$0: cannot deduce hostname"
		exit 1
	}
esac


# Process the rlog output, generating ChangeLog style entries.

# First, reformat the rlog output so that each line contains one log entry.
# Transliterate \n to \r so that multiline entries fit on a single line.
# Discard irrelevant rlog output.
awk <$rlogout '
	/^Working file:/ { filename = $3 }
	/^date: /, /^(-----------*|===========*)$/ {
		if ($0 ~ /^branches: /) { next }
		if ($0 ~ /^date: [0-9][ \/0-9:]*;/) {
			time = substr($3, 1, length($3)-1)
			author = substr($5, 1, length($5)-1)
			printf "%s %s %s %s %c", filename, $2, time, author, 13
			next
		}
		if ($0 ~ /^(-----------*|===========*)$/) { print ""; next }
		printf "%s%c", $0, 13
	}
' |

# Now each line is of the form
# FILENAME YYYY/MM/DD HH:MM:SS AUTHOR \rLOG
#	where \r stands for a carriage return,
#	and each line of the log is terminated by \r instead of \n.
# Sort the log entries, first by date+time (in reverse order),
# then by author, then by log entry, and finally by file name (just in case).
sort +1 -3r +3 +0 |

# Finally, reformat the sorted log entries.
awk '
	BEGIN {
		# Some awks do not understand "\r" or "\013", so we have to
		# put a carriage return directly in the file.
		CR="
" # <-- There is a single CR between the " chars here.

		# Initialize the fullname and mailaddr associative arrays.
		'"$initialize_fullname"'
		'"$initialize_mailaddr"'

		# Initialize indent string.
		indent_string = ""
		i = '"$indent"'
		if (0 < '"$tabwidth"')
			for (;  '"$tabwidth"' <= i;  i -= '"$tabwidth"')
				indent_string = indent_string "\t"
		while (1 <= i--)
			indent_string = indent_string " "

		# Set up date conversion tables.
		# RCS uses a nice, clean, sortable format,
		# but ChangeLog wants the traditional, ugly ctime format.

		# January 1, 0 AD (Gregorian) was Saturday = 6
		EPOCH_WEEKDAY = 6
		# Of course, there was no 0 AD, but the algorithm works anyway.

		w[0]="Sun"; w[1]="Mon"; w[2]="Tue"; w[3]="Wed"
		w[4]="Thu"; w[5]="Fri"; w[6]="Sat"

		'"$month_data"'
	}

	{
		newlog = substr($0, 1 + index($0, CR))

		# Ignore log entries prefixed by "#".
		if (newlog ~ /^#/) { next }

		if (Log != newlog || date != $2 || author != $4) {

			# The previous log and this log differ.

			# Print the old log.
			if (date != "") '"$printlogline"'

			# Logs that begin with "{clumpname} " should be grouped together,
			# and the clumpname should be removed.
			# Extract the new clumpname from the log header,
			# and use it to decide whether to output a blank line.
			newclumpname = ""
			sep = "\n"
			if (date == "") sep = ""
			if (newlog ~ /^\{[^	 }]*}[	 ]/) {
				i = index(newlog, "}")
				newclumpname = substr(newlog, 1, i)
				while (substr(newlog, i+1) ~ /^[	 ]/) i++
				newlog = substr(newlog, i+1)
				if (clumpname == newclumpname) sep = ""
			}
			printf sep
			clumpname = newclumpname

			# Get ready for the next log.
			Log = newlog
			if (files != "")
				for (i in filesknown)
					filesknown[i] = 0
			files = ""
		}
		if (date != $2  ||  author != $4) {
			# The previous date+author and this date+author differ.
			# Print the new one.
			date = $2
			author = $4

			# Convert nice RCS date like "1992/01/03 00:03:44"
			# into ugly ctime date like "Fri Jan  3 00:03:44 1992".
			# Calculate day of week from Gregorian calendar.
			i = index($2, "/")
			year = substr($2, 1, i-1) + 0
			monthday = substr($2, i+1)
			i = index(monthday, "/")
			month = substr(monthday, 1, i-1) + 0
			day = substr(monthday, i+1) + 0
			leap = 0
			if (2 < month && year%4 == 0 && (year%100 != 0 || year%400 == 0)) leap = 1
			days_since_Sunday_before_epoch = EPOCH_WEEKDAY + year * 365 + int((year + 3) / 4) - int((year + 99) / 100) + int((year + 399) / 400) + mo[month-1] + leap + day - 1

			# Print "date  fullname  (email address)".
			# Get fullname and email address from associative arrays;
			# default to author and author@hostname if not in arrays.
			if (fullname[author])
				auth = fullname[author]
			else
				auth = author
			printf "%s %s %2d %s %d  %s  ", w[days_since_Sunday_before_epoch%7], m[month-1], day, $3, year, auth
			if (mailaddr[author])
				printf "(%s)\n\n", mailaddr[author]
			else
				printf "(%s@%s)\n\n", author, "'"$hostname"'"
		}
		if (! filesknown[$1]) {
			filesknown[$1] = 1
			if (files == "") files = " " $1
			else files = files ", " $1
		}
	}
	END {
		# Print the last log.
		if (date != "") {
			'"$printlogline"'
			printf "\n"
		}
	}
' &&


# Exit successfully.

exec rm -f $loginsout $rlogout