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

#! @KSH@

# '@(#)tzselect.ksh	1.7'

# 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 <eggert@twinsun.com>.

# Porting notes:
#
# This script requires several features of the Korn shell.
# If your host lacks the Korn shell,
# you can use either of the following free programs instead:
#
#	<a href=ftp://ftp.gnu.org/pub/gnu/>
#	Bourne-Again shell (bash)
#	</a>
#
#	<a href=ftp://ftp.cs.mun.ca/pub/pdksh/pdksh.tar.gz>
#	Public domain ksh
#	</a>
#
# 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.2,
# you can use either of the following free programs instead:
#
#	<a href=ftp://ftp.gnu.org/pub/gnu/>
#	GNU awk (gawk)
#	</a>
#
#	<a href=ftp://ftp.whidbey.net/pub/brennan/>
#	mawk
#	</a>


# 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
}

# 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
a334319f	3	# '@(#)tzselect.ksh 1.7'
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
a334319f	8	# Contributed by Paul Eggert <eggert@twinsun.com>.
d0045e79 UD	9
	10	# Porting notes:
	11	#
	12	# This script requires several features of the Korn shell.
	13	# If your host lacks the Korn shell,
	14	# you can use either of the following free programs instead:
	15	#
f962d792	16	# <a href=ftp://ftp.gnu.org/pub/gnu/>
d0045e79	17	# Bourne-Again shell (bash)
f962d792	18	# </a>
d0045e79	19	#
f962d792	20	# <a href=ftp://ftp.cs.mun.ca/pub/pdksh/pdksh.tar.gz>
d0045e79	21	# Public domain ksh
f962d792	22	# </a>
d0045e79 UD	23	#
	24	# This script also uses several features of modern awk programs.
	25	# If your host lacks awk, or has an old awk that does not conform to Posix.2,
	26	# you can use either of the following free programs instead:
	27	#
f962d792	28	# <a href=ftp://ftp.gnu.org/pub/gnu/>
d0045e79	29	# GNU awk (gawk)
f962d792	30	# </a>
d0045e79	31	#
f962d792	32	# <a href=ftp://ftp.whidbey.net/pub/brennan/>
d0045e79	33	# mawk
f962d792	34	# </a>
d0045e79 UD	35
	36
	37	# Specify default values for environment variables if they are unset.
	38	: ${AWK=awk}
5290baf0	39	: ${TZDIR=@TZDIR@}
d0045e79 UD	40
	41	# Check for awk Posix compliance.
	42	($AWK -v x=y 'BEGIN { exit 123 }') </dev/null >/dev/null 2>&1
	43	[ $? = 123 ] \|\| {
	44	echo >&2 "$0: Sorry, your \`$AWK' program is not Posix compatible."
	45	exit 1
	46	}
	47
	48	# Make sure the tables are readable.
	49	TZ_COUNTRY_TABLE=$TZDIR/iso3166.tab
	50	TZ_ZONE_TABLE=$TZDIR/zone.tab
	51	for f in $TZ_COUNTRY_TABLE $TZ_ZONE_TABLE
	52	do
	53	<$f \|\| {
	54	echo >&2 "$0: time zone files are not set up correctly"
	55	exit 1
	56	}
	57	done
	58
	59	newline='
	60	'
	61	IFS=$newline
	62
	63
4cca6b86	64	# Work around a bug in bash 1.14.7 and earlier, where $PS3 is sent to stdout.
d0045e79 UD	65	case $(echo 1 \| (select x in x; do break; done) 2>/dev/null) in
	66	?*) PS3=
	67	esac
	68
	69
	70	# Begin the main loop. We come back here if the user wants to retry.
	71	while
	72
	73	echo >&2 'Please identify a location' \
	74	'so that time zone rules can be set correctly.'
	75
	76	continent=
	77	country=
	78	region=
	79
	80
	81	# Ask the user for continent or ocean.
	82
	83	echo >&2 'Please select a continent or ocean.'
	84
	85	select continent in \
	86	Africa \
	87	Americas \
	88	Antarctica \
	89	'Arctic Ocean' \
	90	Asia \
	91	'Atlantic Ocean' \
	92	Australia \
	93	Europe \
	94	'Indian Ocean' \
	95	'Pacific Ocean' \
	96	'none - I want to specify the time zone using the Posix TZ format.'
	97	do
	98	case $continent in
	99	'')
	100	echo >&2 'Please enter a number in range.';;
	101	?*)
	102	case $continent in
	103	Americas) continent=America;;
	104	' ') continent=$(expr "$continent" : '\([^ ]*\)')
	105	esac
	106	break
	107	esac
	108	done
	109	case $continent in
	110	'')
	111	exit 1;;
	112	none)
	113	# Ask the user for a Posix TZ string. Check that it conforms.
	114	while
	115	echo >&2 'Please enter the desired value' \
	116	'of the TZ environment variable.'
	117	echo >&2 'For example, GST-10 is a zone named GST' \
	118	'that is 10 hours ahead (east) of UTC.'
	119	read TZ
	120	$AWK -v TZ="$TZ" 'BEGIN {
	121	tzname = "[^-+,0-9][^-+,0-9][^-+,0-9]+"
	122	time = "[0-2]?[0-9](:[0-5][0-9](:[0-5][0-9])?)?"
	123	offset = "[-+]?" time
	124	date = "(J?[0-9]+\|M[0-9]+\.[0-9]+\.[0-9]+)"
	125	datetime = "," date "(/" time ")?"
	126	tzpattern = "^(:.*\|" tzname offset "(" tzname \
	127	"(" offset ")?(" datetime datetime ")?)?)$"
	128	if (TZ ~ tzpattern) exit 1
129	exit 0
130	}'
131	do
132	echo >&2 "\`$TZ' is not a conforming" \
133	'Posix time zone string.'
134	done
135	TZ_for_date=$TZ;;
136	*)
137	# Get list of names of countries in the continent or ocean.
138	countries=$($AWK -F'\t' \
139	-v continent="$continent" \
140	-v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
141	'
142	/^#/ { next }
143	$3 ~ ("^" continent "/") {
144	if (!cc_seen[$1]++) cc_list[++ccs] = $1
145	}
146	END {
147	while (getline <TZ_COUNTRY_TABLE) {
148	if ($0 !~ /^#/) cc_name[$1] = $2
149	}
150	for (i = 1; i <= ccs; i++) {
151	country = cc_list[i]
152	if (cc_name[country]) {
153	country = cc_name[country]
154	}
155	print country
156	}
157	}
158	' <$TZ_ZONE_TABLE \| sort -f)
159
160
161	# If there's more than one country, ask the user which one.
162	case $countries in
163	"$newline")
164	echo >&2 'Please select a country.'
165	select country in $countries
166	do
167	case $country in
168	'') echo >&2 'Please enter a number in range.';;
169	?*) break
170	esac
171	done
172
173	case $country in
174	'') exit 1
175	esac;;
176	*)
177	country=$countries
178	esac
179
180
181	# Get list of names of time zone rule regions in the country.
182	regions=$($AWK -F'\t' \
183	-v country="$country" \
184	-v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
185	'
186	BEGIN {
187	cc = country
188	while (getline <TZ_COUNTRY_TABLE) {
189	if ($0 !~ /^#/ && country == $2) {
190	cc = $1
191	break
192	}
193	}
194	}
195	$1 == cc { print $4 }
196	' <$TZ_ZONE_TABLE)
197
198
199	# If there's more than one region, ask the user which one.
200	case $regions in
201	"$newline")
202	echo >&2 'Please select one of the following' \
203	'time zone regions.'
204	select region in $regions
205	do
206	case $region in
207	'') echo >&2 'Please enter a number in range.';;
208	?*) break
209	esac
210	done
211	case $region in
212	'') exit 1
213	esac;;
214	*)
215	region=$regions
216	esac
217
218	# Determine TZ from country and region.
219	TZ=$($AWK -F'\t' \
220	-v country="$country" \
221	-v region="$region" \
222	-v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
223	'
224	BEGIN {
225	cc = country
226	while (getline <TZ_COUNTRY_TABLE) {
227	if ($0 !~ /^#/ && country == $2) {
228	cc = $1
229	break
230	}
231	}
232	}
233	$1 == cc && $4 == region { print $3 }
234	' <$TZ_ZONE_TABLE)
235
236	# Make sure the corresponding zoneinfo file exists.
237	TZ_for_date=$TZDIR/$TZ
238	<$TZ_for_date \|\| {
239	echo >&2 "$0: time zone files are not set up correctly"
240	exit 1
241	}
242	esac
243
244
245	# Use the proposed TZ to output the current date relative to UTC.
246	# Loop until they agree in seconds.
247	# Give up after 8 unsuccessful tries.
248
249	extra_info=
250	for i in 1 2 3 4 5 6 7 8
251	do
252	TZdate=$(LANG=C TZ="$TZ_for_date" date)
253	UTdate=$(LANG=C TZ=UTC0 date)
254	TZsec=$(expr "$TZdate" : '.*:\([0-5][0-9]\)')
255	UTsec=$(expr "$UTdate" : '.*:\([0-5][0-9]\)')
256	case $TZsec in
257	$UTsec)
258	extra_info="
259	Local time is now: $TZdate.
260	Universal Time is now: $UTdate."
261	break
262	esac
263	done
264
265
266	# Output TZ info and ask the user to confirm.
267
268	echo >&2 ""
269	echo >&2 "The following information has been given:"
270	echo >&2 ""
271	case $country+$region in
272	?+?) echo >&2 " $country$newline $region";;
273	?*+) echo >&2 " $country";;
274	+) echo >&2 " TZ='$TZ'"
275	esac
276	echo >&2 ""
277	echo >&2 "Therefore TZ='$TZ' will be used.$extra_info"
278	echo >&2 "Is the above information OK?"
279
280	ok=
281	select ok in Yes No
282	do
283	case $ok in
284	'') echo >&2 'Please enter 1 for Yes, or 2 for No.';;
285	?*) break
286	esac
287	done
288	case $ok in
289	'') exit 1;;
290	Yes) break
291	esac
292	do :
293	done
294
a7123f0e UD	295	case $SHELL in
	296	*csh) file=.login line="setenv TZ '$TZ'";;
	297	*) file=.profile line="TZ='$TZ'; export TZ"
	298	esac
	299
	300	echo >&2 "
	301	You can make this change permanent for yourself by appending the line
	302	$line
	303	to the file '$file' in your home directory; then log out and log in again.
	304
	305	Here is that TZ value again, this time on standard output so that you
	306	can use the $0 command in shell scripts:"
	307
d0045e79	308	echo "$TZ"