[thirdparty/glibc.git] / timezone / tzselect.ksh

#! @KSH@

TZVERSION=tz2012i

# Ask the user about the time zone, and output the resulting TZ value to stdout.
# Interact with the user via stderr and stdin.

# Contributed by Paul Eggert.

# Porting notes:
#
# This script requires a Posix-like shell with the extension of a
# 'select' statement.  The 'select' statement was introduced in the
# Korn shell and is available in Bash and other shell implementations.
# If your host lacks both Bash and the Korn shell, you can get their
# source from one of these locations:
#
#	Bash <http://www.gnu.org/software/bash/bash.html>
#	Korn Shell <http://www.kornshell.com/>
#	Public Domain Korn Shell <http://www.cs.mun.ca/~michael/pdksh/>
#
# This script also uses several features of modern awk programs.
# If your host lacks awk, or has an old awk that does not conform to Posix,
# you can use either of the following free programs instead:
#
#	Gawk (GNU awk) <http://www.gnu.org/software/gawk/>
#	mawk <http://invisible-island.net/mawk/>


# Specify default values for environment variables if they are unset.
: ${AWK=awk}
: ${TZDIR=@TZDIR@}

# Check for awk Posix compliance.
($AWK -v x=y 'BEGIN { exit 123 }') </dev/null >/dev/null 2>&1
[ $? = 123 ] || {
	echo >&2 "$0: Sorry, your \`$AWK' program is not Posix compatible."
	exit 1
}

if [ "$1" = "--help" ]; then
    cat <<EOF
Usage: tzselect
Select a time zone interactively.

Report bugs to tz@elsie.nci.nih.gov.
EOF
    exit 0
elif [ "$1" = "--version" ]; then
    cat <<EOF
tzselect $TZVERSION
EOF
    exit 0
fi

# Make sure the tables are readable.
TZ_COUNTRY_TABLE=$TZDIR/iso3166.tab
TZ_ZONE_TABLE=$TZDIR/zone.tab
for f in $TZ_COUNTRY_TABLE $TZ_ZONE_TABLE
do
	<$f || {
		echo >&2 "$0: time zone files are not set up correctly"
		exit 1
	}
done

newline='
'
IFS=$newline


# Work around a bug in bash 1.14.7 and earlier, where $PS3 is sent to stdout.
case $(echo 1 | (select x in x; do break; done) 2>/dev/null) in
?*) PS3=
esac


# Begin the main loop.  We come back here if the user wants to retry.
while

	echo >&2 'Please identify a location' \
		'so that time zone rules can be set correctly.'

	continent=
	country=
	region=


	# Ask the user for continent or ocean.

	echo >&2 'Please select a continent or ocean.'

	select continent in \
	    Africa \
	    Americas \
	    Antarctica \
	    'Arctic Ocean' \
	    Asia \
	    'Atlantic Ocean' \
	    Australia \
	    Europe \
	    'Indian Ocean' \
	    'Pacific Ocean' \
	    'none - I want to specify the time zone using the Posix TZ format.'
	do
	    case $continent in
	    '')
		echo >&2 'Please enter a number in range.';;
	    ?*)
		case $continent in
		Americas) continent=America;;
		*' '*) continent=$(expr "$continent" : '\([^ ]*\)')
		esac
		break
	    esac
	done
	case $continent in
	'')
		exit 1;;
	none)
		# Ask the user for a Posix TZ string.  Check that it conforms.
		while
			echo >&2 'Please enter the desired value' \
				'of the TZ environment variable.'
			echo >&2 'For example, GST-10 is a zone named GST' \
				'that is 10 hours ahead (east) of UTC.'
			read TZ
			$AWK -v TZ="$TZ" 'BEGIN {
				tzname = "[^-+,0-9][^-+,0-9][^-+,0-9]+"
				time = "[0-2]?[0-9](:[0-5][0-9](:[0-5][0-9])?)?"
				offset = "[-+]?" time
				date = "(J?[0-9]+|M[0-9]+\.[0-9]+\.[0-9]+)"
				datetime = "," date "(/" time ")?"
				tzpattern = "^(:.*|" tzname offset "(" tzname \
				  "(" offset ")?(" datetime datetime ")?)?)$"
				if (TZ ~ tzpattern) exit 1
				exit 0
			}'
		do
			echo >&2 "\`$TZ' is not a conforming" \
				'Posix time zone string.'
		done
		TZ_for_date=$TZ;;
	*)
		# Get list of names of countries in the continent or ocean.
		countries=$($AWK -F'\t' \
			-v continent="$continent" \
			-v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
		'
			/^#/ { next }
			$3 ~ ("^" continent "/") {
				if (!cc_seen[$1]++) cc_list[++ccs] = $1
			}
			END {
				while (getline <TZ_COUNTRY_TABLE) {
					if ($0 !~ /^#/) cc_name[$1] = $2
				}
				for (i = 1; i <= ccs; i++) {
					country = cc_list[i]
					if (cc_name[country]) {
					  country = cc_name[country]
					}
					print country
				}
			}
		' <$TZ_ZONE_TABLE | sort -f)


		# If there's more than one country, ask the user which one.
		case $countries in
		*"$newline"*)
			echo >&2 'Please select a country.'
			select country in $countries
			do
			    case $country in
			    '') echo >&2 'Please enter a number in range.';;
			    ?*) break
			    esac
			done

			case $country in
			'') exit 1
			esac;;
		*)
			country=$countries
		esac


		# Get list of names of time zone rule regions in the country.
		regions=$($AWK -F'\t' \
			-v country="$country" \
			-v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
		'
			BEGIN {
				cc = country
				while (getline <TZ_COUNTRY_TABLE) {
					if ($0 !~ /^#/  &&  country == $2) {
						cc = $1
						break
					}
				}
			}
			$1 == cc { print $4 }
		' <$TZ_ZONE_TABLE)


		# If there's more than one region, ask the user which one.
		case $regions in
		*"$newline"*)
			echo >&2 'Please select one of the following' \
				'time zone regions.'
			select region in $regions
			do
				case $region in
				'') echo >&2 'Please enter a number in range.';;
				?*) break
				esac
			done
			case $region in
			'') exit 1
			esac;;
		*)
			region=$regions
		esac

		# Determine TZ from country and region.
		TZ=$($AWK -F'\t' \
			-v country="$country" \
			-v region="$region" \
			-v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
		'
			BEGIN {
				cc = country
				while (getline <TZ_COUNTRY_TABLE) {
					if ($0 !~ /^#/  &&  country == $2) {
						cc = $1
						break
					}
				}
			}
			$1 == cc && $4 == region { print $3 }
		' <$TZ_ZONE_TABLE)

		# Make sure the corresponding zoneinfo file exists.
		TZ_for_date=$TZDIR/$TZ
		<$TZ_for_date || {
			echo >&2 "$0: time zone files are not set up correctly"
			exit 1
		}
	esac


	# Use the proposed TZ to output the current date relative to UTC.
	# Loop until they agree in seconds.
	# Give up after 8 unsuccessful tries.

	extra_info=
	for i in 1 2 3 4 5 6 7 8
	do
		TZdate=$(LANG=C TZ="$TZ_for_date" date)
		UTdate=$(LANG=C TZ=UTC0 date)
		TZsec=$(expr "$TZdate" : '.*:\([0-5][0-9]\)')
		UTsec=$(expr "$UTdate" : '.*:\([0-5][0-9]\)')
		case $TZsec in
		$UTsec)
			extra_info="
Local time is now:	$TZdate.
Universal Time is now:	$UTdate."
			break
		esac
	done


	# Output TZ info and ask the user to confirm.

	echo >&2 ""
	echo >&2 "The following information has been given:"
	echo >&2 ""
	case $country+$region in
	?*+?*)	echo >&2 "	$country$newline	$region";;
	?*+)	echo >&2 "	$country";;
	+)	echo >&2 "	TZ='$TZ'"
	esac
	echo >&2 ""
	echo >&2 "Therefore TZ='$TZ' will be used.$extra_info"
	echo >&2 "Is the above information OK?"

	ok=
	select ok in Yes No
	do
	    case $ok in
	    '') echo >&2 'Please enter 1 for Yes, or 2 for No.';;
	    ?*) break
	    esac
	done
	case $ok in
	'') exit 1;;
	Yes) break
	esac
do :
done

case $SHELL in
*csh) file=.login line="setenv TZ '$TZ'";;
*) file=.profile line="TZ='$TZ'; export TZ"
esac

echo >&2 "
You can make this change permanent for yourself by appending the line
	$line
to the file '$file' in your home directory; then log out and log in again.

Here is that TZ value again, this time on standard output so that you
can use the $0 command in shell scripts:"

echo "$TZ"
Commit	Line	Data
5290baf0	1	#! @KSH@
a7123f0e	2
92e4b6a9	3	TZVERSION=tz2012i
a7123f0e	4
d0045e79 UD	5	# Ask the user about the time zone, and output the resulting TZ value to stdout.
	6	# Interact with the user via stderr and stdin.
	7
c872f5cc	8	# Contributed by Paul Eggert.
d0045e79 UD	9
	10	# Porting notes:
	11	#
92e4b6a9 JM	12	# This script requires a Posix-like shell with the extension of a
	13	# 'select' statement. The 'select' statement was introduced in the
	14	# Korn shell and is available in Bash and other shell implementations.
	15	# If your host lacks both Bash and the Korn shell, you can get their
	16	# source from one of these locations:
d0045e79	17	#
92e4b6a9 JM	18	# Bash <http://www.gnu.org/software/bash/bash.html>
	19	# Korn Shell <http://www.kornshell.com/>
	20	# Public Domain Korn Shell <http://www.cs.mun.ca/~michael/pdksh/>
d0045e79 UD	21	#
d0045e79 UD	22	# This script also uses several features of modern awk programs.
92e4b6a9	23	# If your host lacks awk, or has an old awk that does not conform to Posix,
d0045e79 UD	24	# you can use either of the following free programs instead:
d0045e79 UD	25	#
92e4b6a9 JM	26	# Gawk (GNU awk) <http://www.gnu.org/software/gawk/>
92e4b6a9 JM	27	# mawk <http://invisible-island.net/mawk/>
d0045e79 UD	28
	29
	30	# Specify default values for environment variables if they are unset.
	31	: ${AWK=awk}
5290baf0	32	: ${TZDIR=@TZDIR@}
d0045e79 UD	33
	34	# Check for awk Posix compliance.
	35	($AWK -v x=y 'BEGIN { exit 123 }') </dev/null >/dev/null 2>&1
	36	[ $? = 123 ] \|\| {
	37	echo >&2 "$0: Sorry, your \`$AWK' program is not Posix compatible."
	38	exit 1
	39	}
	40
5fb55a68 UD	41	if [ "$1" = "--help" ]; then
	42	cat <<EOF
	43	Usage: tzselect
	44	Select a time zone interactively.
	45
	46	Report bugs to tz@elsie.nci.nih.gov.
	47	EOF
	48	exit 0
	49	elif [ "$1" = "--version" ]; then
	50	cat <<EOF
92e4b6a9	51	tzselect $TZVERSION
5fb55a68 UD	52	EOF
	53	exit 0
	54	fi
	55
d0045e79 UD	56	# Make sure the tables are readable.
	57	TZ_COUNTRY_TABLE=$TZDIR/iso3166.tab
	58	TZ_ZONE_TABLE=$TZDIR/zone.tab
	59	for f in $TZ_COUNTRY_TABLE $TZ_ZONE_TABLE
	60	do
	61	<$f \|\| {
	62	echo >&2 "$0: time zone files are not set up correctly"
	63	exit 1
	64	}
	65	done
	66
	67	newline='
	68	'
	69	IFS=$newline
	70
	71
4cca6b86	72	# Work around a bug in bash 1.14.7 and earlier, where $PS3 is sent to stdout.
d0045e79 UD	73	case $(echo 1 \| (select x in x; do break; done) 2>/dev/null) in
	74	?*) PS3=
	75	esac
	76
	77
	78	# Begin the main loop. We come back here if the user wants to retry.
	79	while
	80
	81	echo >&2 'Please identify a location' \
	82	'so that time zone rules can be set correctly.'
	83
	84	continent=
	85	country=
	86	region=
	87
	88
	89	# Ask the user for continent or ocean.
	90
	91	echo >&2 'Please select a continent or ocean.'
	92
	93	select continent in \
	94	Africa \
	95	Americas \
	96	Antarctica \
	97	'Arctic Ocean' \
	98	Asia \
	99	'Atlantic Ocean' \
	100	Australia \
	101	Europe \
	102	'Indian Ocean' \
	103	'Pacific Ocean' \
	104	'none - I want to specify the time zone using the Posix TZ format.'
	105	do
	106	case $continent in
	107	'')
	108	echo >&2 'Please enter a number in range.';;
	109	?*)
	110	case $continent in
	111	Americas) continent=America;;
	112	' ') continent=$(expr "$continent" : '\([^ ]*\)')
	113	esac
	114	break
	115	esac
	116	done
	117	case $continent in
	118	'')
	119	exit 1;;
	120	none)
	121	# Ask the user for a Posix TZ string. Check that it conforms.
	122	while
	123	echo >&2 'Please enter the desired value' \
	124	'of the TZ environment variable.'
	125	echo >&2 'For example, GST-10 is a zone named GST' \
	126	'that is 10 hours ahead (east) of UTC.'
	127	read TZ
	128	$AWK -v TZ="$TZ" 'BEGIN {
	129	tzname = "[^-+,0-9][^-+,0-9][^-+,0-9]+"
	130	time = "[0-2]?[0-9](:[0-5][0-9](:[0-5][0-9])?)?"
	131	offset = "[-+]?" time
	132	date = "(J?[0-9]+\|M[0-9]+\.[0-9]+\.[0-9]+)"
	133	datetime = "," date "(/" time ")?"
	134	tzpattern = "^(:.*\|" tzname offset "(" tzname \
	135	"(" offset ")?(" datetime datetime ")?)?)$"
	136	if (TZ ~ tzpattern) exit 1
137	exit 0
138	}'
139	do
140	echo >&2 "\`$TZ' is not a conforming" \
141	'Posix time zone string.'
142	done
143	TZ_for_date=$TZ;;
144	*)
145	# Get list of names of countries in the continent or ocean.
146	countries=$($AWK -F'\t' \
147	-v continent="$continent" \
148	-v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
149	'
150	/^#/ { next }
151	$3 ~ ("^" continent "/") {
152	if (!cc_seen[$1]++) cc_list[++ccs] = $1
153	}
154	END {
155	while (getline <TZ_COUNTRY_TABLE) {
156	if ($0 !~ /^#/) cc_name[$1] = $2
157	}
158	for (i = 1; i <= ccs; i++) {
159	country = cc_list[i]
160	if (cc_name[country]) {
161	country = cc_name[country]
162	}
163	print country
164	}
165	}
166	' <$TZ_ZONE_TABLE \| sort -f)
167
168
169	# If there's more than one country, ask the user which one.
170	case $countries in
171	"$newline")
172	echo >&2 'Please select a country.'
173	select country in $countries
174	do
175	case $country in
176	'') echo >&2 'Please enter a number in range.';;
177	?*) break
178	esac
179	done
180
181	case $country in
182	'') exit 1
183	esac;;
184	*)
185	country=$countries
186	esac
187
188
189	# Get list of names of time zone rule regions in the country.
190	regions=$($AWK -F'\t' \
191	-v country="$country" \
192	-v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
193	'
194	BEGIN {
195	cc = country
196	while (getline <TZ_COUNTRY_TABLE) {
197	if ($0 !~ /^#/ && country == $2) {
198	cc = $1
199	break
200	}
201	}
202	}
203	$1 == cc { print $4 }
204	' <$TZ_ZONE_TABLE)
205
206
207	# If there's more than one region, ask the user which one.
208	case $regions in
209	"$newline")
210	echo >&2 'Please select one of the following' \
211	'time zone regions.'
212	select region in $regions
213	do
214	case $region in
215	'') echo >&2 'Please enter a number in range.';;
216	?*) break
217	esac
218	done
219	case $region in
220	'') exit 1
221	esac;;
222	*)
223	region=$regions
224	esac
225
226	# Determine TZ from country and region.
227	TZ=$($AWK -F'\t' \
228	-v country="$country" \
229	-v region="$region" \
230	-v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
231	'
232	BEGIN {
233	cc = country
234	while (getline <TZ_COUNTRY_TABLE) {
235	if ($0 !~ /^#/ && country == $2) {
236	cc = $1
237	break
238	}
239	}
240	}
241	$1 == cc && $4 == region { print $3 }
242	' <$TZ_ZONE_TABLE)
243
244	# Make sure the corresponding zoneinfo file exists.
245	TZ_for_date=$TZDIR/$TZ
246	<$TZ_for_date \|\| {
247	echo >&2 "$0: time zone files are not set up correctly"
248	exit 1
249	}
250	esac
251
252
253	# Use the proposed TZ to output the current date relative to UTC.
254	# Loop until they agree in seconds.
255	# Give up after 8 unsuccessful tries.
256
257	extra_info=
258	for i in 1 2 3 4 5 6 7 8
259	do
260	TZdate=$(LANG=C TZ="$TZ_for_date" date)
261	UTdate=$(LANG=C TZ=UTC0 date)
262	TZsec=$(expr "$TZdate" : '.*:\([0-5][0-9]\)')
263	UTsec=$(expr "$UTdate" : '.*:\([0-5][0-9]\)')
264	case $TZsec in
265	$UTsec)
266	extra_info="
267	Local time is now: $TZdate.
268	Universal Time is now: $UTdate."
269	break
270	esac
271	done
272
273
274	# Output TZ info and ask the user to confirm.
275
276	echo >&2 ""
277	echo >&2 "The following information has been given:"
278	echo >&2 ""
279	case $country+$region in
280	?+?) echo >&2 " $country$newline $region";;
281	?*+) echo >&2 " $country";;
282	+) echo >&2 " TZ='$TZ'"
283	esac
284	echo >&2 ""
285	echo >&2 "Therefore TZ='$TZ' will be used.$extra_info"
286	echo >&2 "Is the above information OK?"
287
288	ok=
289	select ok in Yes No
290	do
291	case $ok in
292	'') echo >&2 'Please enter 1 for Yes, or 2 for No.';;
293	?*) break
294	esac
295	done
296	case $ok in
297	'') exit 1;;
298	Yes) break
299	esac
300	do :
301	done
302
a7123f0e UD	303	case $SHELL in
	304	*csh) file=.login line="setenv TZ '$TZ'";;
	305	*) file=.profile line="TZ='$TZ'; export TZ"
	306	esac
	307
	308	echo >&2 "
	309	You can make this change permanent for yourself by appending the line
	310	$line
	311	to the file '$file' in your home directory; then log out and log in again.
	312
	313	Here is that TZ value again, this time on standard output so that you
	314	can use the $0 command in shell scripts:"
	315
d0045e79	316	echo "$TZ"