commit: 0af4e76511a1235990e10d0e616a261cb6a4714f
Author: Kerin Millar <kfm <AT> plushkava <DOT> net>
AuthorDate: Fri Feb 17 03:04:49 2023 +0000
Commit: Sam James <sam <AT> gentoo <DOT> org>
CommitDate: Fri Feb 17 07:36:59 2023 +0000
URL:
https://gitweb.gentoo.org/proj/gentoo-functions.git/commit/?id=0af4e765
Improve the legibility of the routine that detects the number of columns
Also, mention that the use of stty size is portable as of POSIX Issue 8.
Signed-off-by: Kerin Millar <kfm <AT> plushkava.net>
Signed-off-by: Sam James <sam <AT> gentoo.org>
functions.sh | 52 ++++++++++++++++++++++++++++------------------------
1 file changed, 28 insertions(+), 24 deletions(-)
diff --git a/functions.sh b/functions.sh
index df72d4a..02627d2 100644
--- a/functions.sh
+++ b/functions.sh
@@ -492,32 +492,36 @@ for arg in "$@" ; do
done
# Try to determine the number of available columns in the terminal.
-# shellcheck disable=3044
-if [ -n "${BASH}" ] && shopt -s checkwinsize 2>/dev/null; then
- # As is documented, running an external command will cause bash to set
- # the COLUMNS variable. This technique is effective for >=4.3, though
- # it requires for the checkwinsize shopt to be enabled. By default, it
- # is only enabled for >=5.0.
- /bin/true
-fi
-if is_int "${COLUMNS}" && [ "${COLUMNS}" -gt 0 ]; then
- # The value of COLUMNS was likely set by a shell such as bash or mksh.
- genfun_cols=${COLUMNS}
-else
- # Try to use stty(1) to determine the number of columns. The use of the
- # size operand is not portable.
- genfun_cols=$(
- stty size 2>/dev/null | {
- if IFS=' ' read -r _ cols _; then
- printf '%s\n' "${cols}"
+for _ in 1 2 3; do
+ case $_ in
+ 1)
+ # Running an external command causes bash >=4.3 to set
+ # the COLUMNS variable, provided that the checkwinsize
+ # shopt is enabled. As of 5.0, it's enabled by default.
+ # shellcheck disable=3044
+ if [ -n "${BASH}" ] && shopt -s checkwinsize
2>/dev/null; then
+ /bin/true
fi
- }
- )
- if ! is_int "${genfun_cols}" || [ "${genfun_cols}" -le 0 ]; then
- # Give up and assume 80 available columns.
- genfun_cols=80
+ genfun_cols=${COLUMNS}
+ ;;
+ 2)
+ # This use of stty(1) is portable as of POSIX Issue 8.
+ genfun_cols=$(
+ stty size 2>/dev/null | {
+ if IFS=' ' read -r _ cols; then
+ printf '%s\n' "${cols}"
+ fi
+ }
+ )
+ ;;
+ 3)
+ # Give up and assume 80 available columns.
+ genfun_cols=80
+ esac
+ if is_int "${genfun_cols}" && [ "${genfun_cols}" -gt 0 ]; then
+ break
fi
-fi
+done
# Set an ECMA-48 CSI sequence, allowing for eend to line up the [ ok ] string.
{
