559 lines
15 KiB
Plaintext
559 lines
15 KiB
Plaintext
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#!/arm/tools/gnu/bash/4.2/rhe6-x86_64/bin/bash
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# Ask the user about the time zone, and output the resulting TZ value to stdout.
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# Interact with the user via stderr and stdin.
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PKGVERSION="(GNU Toolchain for the A-profile Architecture 9.2-2019.12 (arm-9.10)) "
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TZVERSION="2.30"
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REPORT_BUGS_TO="<https://bugs.linaro.org/>"
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# Contributed by Paul Eggert. This file is in the public domain.
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# Porting notes:
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#
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# This script requires a Posix-like shell and prefers the extension of a
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# 'select' statement. The 'select' statement was introduced in the
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# Korn shell and is available in Bash and other shell implementations.
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# If your host lacks both Bash and the Korn shell, you can get their
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# source from one of these locations:
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#
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# Bash <https://www.gnu.org/software/bash/>
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# Korn Shell <http://www.kornshell.com/>
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# MirBSD Korn Shell <https://www.mirbsd.org/mksh.htm>
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#
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# For portability to Solaris 9 /bin/sh this script avoids some POSIX
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# features and common extensions, such as $(...) (which works sometimes
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# but not others), $((...)), and $10.
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#
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# This script also uses several features of modern awk programs.
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# If your host lacks awk, or has an old awk that does not conform to Posix,
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# you can use either of the following free programs instead:
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#
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# Gawk (GNU awk) <https://www.gnu.org/software/gawk/>
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# mawk <https://invisible-island.net/mawk/>
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# Specify default values for environment variables if they are unset.
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: ${AWK=awk}
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: ${TZDIR=/usr/share/zoneinfo}
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# Output one argument as-is to standard output.
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# Safer than 'echo', which can mishandle '\' or leading '-'.
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say() {
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printf '%s\n' "$1"
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}
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# Check for awk Posix compliance.
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($AWK -v x=y 'BEGIN { exit 123 }') </dev/null >/dev/null 2>&1
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[ $? = 123 ] || {
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say >&2 "$0: Sorry, your '$AWK' program is not Posix compatible."
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exit 1
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}
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coord=
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location_limit=10
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zonetabtype=zone1970
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usage="Usage: tzselect [--version] [--help] [-c COORD] [-n LIMIT]
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Select a timezone interactively.
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Options:
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-c COORD
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Instead of asking for continent and then country and then city,
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ask for selection from time zones whose largest cities
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are closest to the location with geographical coordinates COORD.
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COORD should use ISO 6709 notation, for example, '-c +4852+00220'
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for Paris (in degrees and minutes, North and East), or
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'-c -35-058' for Buenos Aires (in degrees, South and West).
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-n LIMIT
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Display at most LIMIT locations when -c is used (default $location_limit).
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--version
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Output version information.
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--help
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Output this help.
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Report bugs to $REPORT_BUGS_TO."
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# Ask the user to select from the function's arguments,
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# and assign the selected argument to the variable 'select_result'.
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# Exit on EOF or I/O error. Use the shell's 'select' builtin if available,
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# falling back on a less-nice but portable substitute otherwise.
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if
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case $BASH_VERSION in
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?*) : ;;
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'')
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# '; exit' should be redundant, but Dash doesn't properly fail without it.
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(eval 'set --; select x; do break; done; exit') </dev/null 2>/dev/null
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esac
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then
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# Do this inside 'eval', as otherwise the shell might exit when parsing it
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# even though it is never executed.
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eval '
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doselect() {
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select select_result
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do
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case $select_result in
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"") echo >&2 "Please enter a number in range." ;;
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?*) break
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esac
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done || exit
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}
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# Work around a bug in bash 1.14.7 and earlier, where $PS3 is sent to stdout.
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case $BASH_VERSION in
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[01].*)
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case `echo 1 | (select x in x; do break; done) 2>/dev/null` in
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?*) PS3=
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esac
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esac
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'
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else
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doselect() {
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# Field width of the prompt numbers.
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select_width=`expr $# : '.*'`
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select_i=
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while :
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do
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case $select_i in
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'')
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select_i=0
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for select_word
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do
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select_i=`expr $select_i + 1`
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printf >&2 "%${select_width}d) %s\\n" $select_i "$select_word"
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done ;;
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*[!0-9]*)
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echo >&2 'Please enter a number in range.' ;;
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*)
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if test 1 -le $select_i && test $select_i -le $#; then
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shift `expr $select_i - 1`
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select_result=$1
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break
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fi
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echo >&2 'Please enter a number in range.'
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esac
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# Prompt and read input.
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printf >&2 %s "${PS3-#? }"
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read select_i || exit
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done
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}
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fi
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while getopts c:n:t:-: opt
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do
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case $opt$OPTARG in
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c*)
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coord=$OPTARG ;;
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n*)
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location_limit=$OPTARG ;;
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t*) # Undocumented option, used for developer testing.
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zonetabtype=$OPTARG ;;
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-help)
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exec echo "$usage" ;;
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-version)
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exec echo "tzselect $PKGVERSION$TZVERSION" ;;
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-*)
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say >&2 "$0: -$opt$OPTARG: unknown option; try '$0 --help'"; exit 1 ;;
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*)
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say >&2 "$0: try '$0 --help'"; exit 1 ;;
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esac
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done
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shift `expr $OPTIND - 1`
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case $# in
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0) ;;
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*) say >&2 "$0: $1: unknown argument"; exit 1 ;;
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esac
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# Make sure the tables are readable.
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TZ_COUNTRY_TABLE=$TZDIR/iso3166.tab
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TZ_ZONE_TABLE=$TZDIR/$zonetabtype.tab
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for f in $TZ_COUNTRY_TABLE $TZ_ZONE_TABLE
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do
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<"$f" || {
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say >&2 "$0: time zone files are not set up correctly"
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exit 1
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}
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done
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# If the current locale does not support UTF-8, convert data to current
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# locale's format if possible, as the shell aligns columns better that way.
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# Check the UTF-8 of U+12345 CUNEIFORM SIGN URU TIMES KI.
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! $AWK 'BEGIN { u12345 = "\360\222\215\205"; exit length(u12345) != 1 }' &&
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{ tmp=`(mktemp -d) 2>/dev/null` || {
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tmp=${TMPDIR-/tmp}/tzselect.$$ &&
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(umask 77 && mkdir -- "$tmp")
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};} &&
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trap 'status=$?; rm -fr -- "$tmp"; exit $status' 0 HUP INT PIPE TERM &&
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(iconv -f UTF-8 -t //TRANSLIT <"$TZ_COUNTRY_TABLE" >$tmp/iso3166.tab) \
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2>/dev/null &&
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TZ_COUNTRY_TABLE=$tmp/iso3166.tab &&
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iconv -f UTF-8 -t //TRANSLIT <"$TZ_ZONE_TABLE" >$tmp/$zonetabtype.tab &&
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TZ_ZONE_TABLE=$tmp/$zonetabtype.tab
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newline='
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'
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IFS=$newline
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# Awk script to read a time zone table and output the same table,
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# with each column preceded by its distance from 'here'.
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output_distances='
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BEGIN {
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FS = "\t"
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while (getline <TZ_COUNTRY_TABLE)
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if ($0 ~ /^[^#]/)
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country[$1] = $2
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country["US"] = "US" # Otherwise the strings get too long.
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}
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function abs(x) {
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return x < 0 ? -x : x;
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}
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function min(x, y) {
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return x < y ? x : y;
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}
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function convert_coord(coord, deg, minute, ilen, sign, sec) {
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if (coord ~ /^[-+]?[0-9]?[0-9][0-9][0-9][0-9][0-9][0-9]([^0-9]|$)/) {
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degminsec = coord
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intdeg = degminsec < 0 ? -int(-degminsec / 10000) : int(degminsec / 10000)
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minsec = degminsec - intdeg * 10000
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intmin = minsec < 0 ? -int(-minsec / 100) : int(minsec / 100)
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sec = minsec - intmin * 100
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deg = (intdeg * 3600 + intmin * 60 + sec) / 3600
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} else if (coord ~ /^[-+]?[0-9]?[0-9][0-9][0-9][0-9]([^0-9]|$)/) {
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degmin = coord
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intdeg = degmin < 0 ? -int(-degmin / 100) : int(degmin / 100)
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minute = degmin - intdeg * 100
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deg = (intdeg * 60 + minute) / 60
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} else
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deg = coord
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return deg * 0.017453292519943296
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}
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function convert_latitude(coord) {
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match(coord, /..*[-+]/)
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return convert_coord(substr(coord, 1, RLENGTH - 1))
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}
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function convert_longitude(coord) {
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match(coord, /..*[-+]/)
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return convert_coord(substr(coord, RLENGTH))
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}
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# Great-circle distance between points with given latitude and longitude.
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# Inputs and output are in radians. This uses the great-circle special
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# case of the Vicenty formula for distances on ellipsoids.
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function gcdist(lat1, long1, lat2, long2, dlong, x, y, num, denom) {
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dlong = long2 - long1
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x = cos(lat2) * sin(dlong)
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y = cos(lat1) * sin(lat2) - sin(lat1) * cos(lat2) * cos(dlong)
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num = sqrt(x * x + y * y)
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denom = sin(lat1) * sin(lat2) + cos(lat1) * cos(lat2) * cos(dlong)
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return atan2(num, denom)
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}
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# Parallel distance between points with given latitude and longitude.
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# This is the product of the longitude difference and the cosine
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# of the latitude of the point that is further from the equator.
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# I.e., it considers longitudes to be further apart if they are
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# nearer the equator.
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function pardist(lat1, long1, lat2, long2) {
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return abs(long1 - long2) * min(cos(lat1), cos(lat2))
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}
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# The distance function is the sum of the great-circle distance and
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# the parallel distance. It could be weighted.
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function dist(lat1, long1, lat2, long2) {
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return gcdist(lat1, long1, lat2, long2) + pardist(lat1, long1, lat2, long2)
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}
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BEGIN {
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coord_lat = convert_latitude(coord)
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coord_long = convert_longitude(coord)
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}
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/^[^#]/ {
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here_lat = convert_latitude($2)
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here_long = convert_longitude($2)
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line = $1 "\t" $2 "\t" $3
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sep = "\t"
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ncc = split($1, cc, /,/)
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for (i = 1; i <= ncc; i++) {
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line = line sep country[cc[i]]
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sep = ", "
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}
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if (NF == 4)
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line = line " - " $4
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printf "%g\t%s\n", dist(coord_lat, coord_long, here_lat, here_long), line
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}
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'
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# Begin the main loop. We come back here if the user wants to retry.
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while
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echo >&2 'Please identify a location' \
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'so that time zone rules can be set correctly.'
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continent=
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country=
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region=
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case $coord in
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?*)
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continent=coord;;
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'')
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# Ask the user for continent or ocean.
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echo >&2 'Please select a continent, ocean, "coord", or "TZ".'
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quoted_continents=`
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$AWK '
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BEGIN { FS = "\t" }
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/^[^#]/ {
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entry = substr($3, 1, index($3, "/") - 1)
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if (entry == "America")
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entry = entry "s"
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if (entry ~ /^(Arctic|Atlantic|Indian|Pacific)$/)
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entry = entry " Ocean"
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printf "'\''%s'\''\n", entry
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}
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' <"$TZ_ZONE_TABLE" |
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sort -u |
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tr '\n' ' '
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echo ''
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`
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eval '
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doselect '"$quoted_continents"' \
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"coord - I want to use geographical coordinates." \
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"TZ - I want to specify the timezone using the Posix TZ format."
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continent=$select_result
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case $continent in
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Americas) continent=America;;
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*" "*) continent=`expr "$continent" : '\''\([^ ]*\)'\''`
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esac
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'
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esac
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case $continent in
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TZ)
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# Ask the user for a Posix TZ string. Check that it conforms.
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while
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echo >&2 'Please enter the desired value' \
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'of the TZ environment variable.'
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echo >&2 'For example, AEST-10 is abbreviated' \
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'AEST and is 10 hours'
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echo >&2 'ahead (east) of Greenwich,' \
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'with no daylight saving time.'
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read TZ
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$AWK -v TZ="$TZ" 'BEGIN {
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tzname = "(<[[:alnum:]+-]{3,}>|[[:alpha:]]{3,})"
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time = "(2[0-4]|[0-1]?[0-9])" \
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"(:[0-5][0-9](:[0-5][0-9])?)?"
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offset = "[-+]?" time
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mdate = "M([1-9]|1[0-2])\\.[1-5]\\.[0-6]"
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jdate = "((J[1-9]|[0-9]|J?[1-9][0-9]" \
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"|J?[1-2][0-9][0-9])|J?3[0-5][0-9]|J?36[0-5])"
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datetime = ",(" mdate "|" jdate ")(/" time ")?"
|
||
|
|
tzpattern = "^(:.*|" tzname offset "(" tzname \
|
||
|
|
"(" offset ")?(" datetime datetime ")?)?)$"
|
||
|
|
if (TZ ~ tzpattern) exit 1
|
||
|
|
exit 0
|
||
|
|
}'
|
||
|
|
do
|
||
|
|
say >&2 "'$TZ' is not a conforming Posix timezone string."
|
||
|
|
done
|
||
|
|
TZ_for_date=$TZ;;
|
||
|
|
*)
|
||
|
|
case $continent in
|
||
|
|
coord)
|
||
|
|
case $coord in
|
||
|
|
'')
|
||
|
|
echo >&2 'Please enter coordinates' \
|
||
|
|
'in ISO 6709 notation.'
|
||
|
|
echo >&2 'For example, +4042-07403 stands for'
|
||
|
|
echo >&2 '40 degrees 42 minutes north,' \
|
||
|
|
'74 degrees 3 minutes west.'
|
||
|
|
read coord;;
|
||
|
|
esac
|
||
|
|
distance_table=`$AWK \
|
||
|
|
-v coord="$coord" \
|
||
|
|
-v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
|
||
|
|
"$output_distances" <"$TZ_ZONE_TABLE" |
|
||
|
|
sort -n |
|
||
|
|
sed "${location_limit}q"
|
||
|
|
`
|
||
|
|
regions=`say "$distance_table" | $AWK '
|
||
|
|
BEGIN { FS = "\t" }
|
||
|
|
{ print $NF }
|
||
|
|
'`
|
||
|
|
echo >&2 'Please select one of the following timezones,' \
|
||
|
|
echo >&2 'listed roughly in increasing order' \
|
||
|
|
"of distance from $coord".
|
||
|
|
doselect $regions
|
||
|
|
region=$select_result
|
||
|
|
TZ=`say "$distance_table" | $AWK -v region="$region" '
|
||
|
|
BEGIN { FS="\t" }
|
||
|
|
$NF == region { print $4 }
|
||
|
|
'`
|
||
|
|
;;
|
||
|
|
*)
|
||
|
|
# Get list of names of countries in the continent or ocean.
|
||
|
|
countries=`$AWK \
|
||
|
|
-v continent="$continent" \
|
||
|
|
-v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
|
||
|
|
'
|
||
|
|
BEGIN { FS = "\t" }
|
||
|
|
/^#/ { next }
|
||
|
|
$3 ~ ("^" continent "/") {
|
||
|
|
ncc = split($1, cc, /,/)
|
||
|
|
for (i = 1; i <= ncc; i++)
|
||
|
|
if (!cc_seen[cc[i]]++) cc_list[++ccs] = cc[i]
|
||
|
|
}
|
||
|
|
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' \
|
||
|
|
'whose clocks agree with yours.'
|
||
|
|
doselect $countries
|
||
|
|
country=$select_result;;
|
||
|
|
*)
|
||
|
|
country=$countries
|
||
|
|
esac
|
||
|
|
|
||
|
|
|
||
|
|
# Get list of timezones in the country.
|
||
|
|
regions=`$AWK \
|
||
|
|
-v country="$country" \
|
||
|
|
-v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
|
||
|
|
'
|
||
|
|
BEGIN {
|
||
|
|
FS = "\t"
|
||
|
|
cc = country
|
||
|
|
while (getline <TZ_COUNTRY_TABLE) {
|
||
|
|
if ($0 !~ /^#/ && country == $2) {
|
||
|
|
cc = $1
|
||
|
|
break
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
/^#/ { next }
|
||
|
|
$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 timezones.'
|
||
|
|
doselect $regions
|
||
|
|
region=$select_result;;
|
||
|
|
*)
|
||
|
|
region=$regions
|
||
|
|
esac
|
||
|
|
|
||
|
|
# Determine TZ from country and region.
|
||
|
|
TZ=`$AWK \
|
||
|
|
-v country="$country" \
|
||
|
|
-v region="$region" \
|
||
|
|
-v TZ_COUNTRY_TABLE="$TZ_COUNTRY_TABLE" \
|
||
|
|
'
|
||
|
|
BEGIN {
|
||
|
|
FS = "\t"
|
||
|
|
cc = country
|
||
|
|
while (getline <TZ_COUNTRY_TABLE) {
|
||
|
|
if ($0 !~ /^#/ && country == $2) {
|
||
|
|
cc = $1
|
||
|
|
break
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
/^#/ { next }
|
||
|
|
$1 ~ cc && $4 == region { print $3 }
|
||
|
|
' <"$TZ_ZONE_TABLE"`
|
||
|
|
esac
|
||
|
|
|
||
|
|
# Make sure the corresponding zoneinfo file exists.
|
||
|
|
TZ_for_date=$TZDIR/$TZ
|
||
|
|
<"$TZ_for_date" || {
|
||
|
|
say >&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="
|
||
|
|
Selected 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%$coord in
|
||
|
|
?*%?*%) say >&2 " $country$newline $region";;
|
||
|
|
?*%%) say >&2 " $country";;
|
||
|
|
%?*%?*) say >&2 " coord $coord$newline $region";;
|
||
|
|
%%?*) say >&2 " coord $coord";;
|
||
|
|
*) say >&2 " TZ='$TZ'"
|
||
|
|
esac
|
||
|
|
say >&2 ""
|
||
|
|
say >&2 "Therefore TZ='$TZ' will be used.$extra_info"
|
||
|
|
say >&2 "Is the above information OK?"
|
||
|
|
|
||
|
|
doselect Yes No
|
||
|
|
ok=$select_result
|
||
|
|
case $ok in
|
||
|
|
Yes) break
|
||
|
|
esac
|
||
|
|
do coord=
|
||
|
|
done
|
||
|
|
|
||
|
|
case $SHELL in
|
||
|
|
*csh) file=.login line="setenv TZ '$TZ'";;
|
||
|
|
*) file=.profile line="TZ='$TZ'; export TZ"
|
||
|
|
esac
|
||
|
|
|
||
|
|
test -t 1 && say >&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 $0 command in shell scripts:"
|
||
|
|
|
||
|
|
say "$TZ"
|