Use POSIX version of version.c.

1 files changed, 292 insertions, 0 deletions

diff --git a/time/tzselect.ksh b/time/tzselect.ksh
new file mode 100644
index 0000000..0f0a3bb
--- /dev/null
+++ b/time/tzselect.ksh
@@ -0,0 +1,292 @@
+#! /bin/ksh
+# 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:
+#
+#	Bourne-Again shell (bash)
+#	<URL:ftp://prep.ai.mit.edu:/pub/gnu/bash-1.14.7.tar.gz>
+#	(or any later version)
+#
+#	Public domain ksh
+#	<URL:ftp://ftp.cs.mun.ca:/pub/pdksh/pdksh.tar.gz>
+#
+# 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:
+#
+#	GNU awk (gawk)
+#	<URL:ftp://prep.ai.mit.edu:/pub/gnu/gawk-3.0.0.tar.gz>
+#	(or any later version)
+#
+#	mawk
+#	<URL:ftp://oxy.edu/public/mawk1.2.2.tar.gz>
+#	(or any later version)
+
+
+# Specify default values for environment variables if they are unset.
+: ${AWK=awk}
+: ${TZDIR=$(pwd)}
+
+# 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 bash bug, 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 $ok in
+	'') exit 1;;
+	Yes) break
+	esac
+do :
+done
+
+# Output the answer.
+echo "$TZ"