70 lines
2.1 KiB
Diff
70 lines
2.1 KiB
Diff
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From 98087d78eda2ca58a3b55ee5dd9e0e7bad8467ef Mon Sep 17 00:00:00 2001
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From: Tao Liu <ltao@redhat.com>
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Date: Tue, 25 Jun 2024 16:35:16 +1200
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Subject: [PATCH] Use "grep -q <<< $(cmd)" instead of "cmd | grep -q"
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The following line of code's exit value should be the exit value of
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grep by default:
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cmd | grep -q
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However it will not always work as expected, a 141 exit code may be
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returned, see the following debug info:
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//--- a/usr/lib/dracut/modules.d/99kdumpbase/module-setup.sh
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//+++ b/usr/lib/dracut/modules.d/99kdumpbase/module-setup.sh
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//@@ -55,6 +55,11 @@ depends() {
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// _dep="$_dep ssh-client"
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// fi
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//
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//+ dracut --list-modules 1>&2
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//+ echo $? 1>&2
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//+ dracut --list-modules | grep -q lvmthinpool-monitor
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//+ echo $? ${PIPESTATUS[0]} ${PIPESTATUS[1]} 1>&2
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//+
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// if is_lvm2_thinp_dump_target; then
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// if dracut --list-modules | grep -q lvmthinpool-monitor; then
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// add_opt_module lvmthinpool-monitor
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$ kdumpctl rebuild
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kdump: Rebuilding /boot/initramfs-6.10.0-0.rc4.11.el10.x86_64kdump.img
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...snip...
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lvmmerge
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lvmthinpool-monitor
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..snip...
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uefi-lib
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0
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141 141 0
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The reason is, grep exits immediately when there is a match but the
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first cmd still keep writing to the pipe. Since there is no reader,
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a SIGPIPE signal is generated. As a result, a 141 exit code will be
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returned.
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Let's use the following line of code instead, which have the same effect
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but works as expected:
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grep -q <<< $(cmd)
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Signed-off-by: Tao Liu <ltao@redhat.com>
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---
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dracut-module-setup.sh | 2 +-
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1 file changed, 1 insertion(+), 1 deletion(-)
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diff --git a/dracut-module-setup.sh b/dracut-module-setup.sh
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index 89d9959..76fb5b2 100755
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--- a/dracut-module-setup.sh
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+++ b/dracut-module-setup.sh
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@@ -56,7 +56,7 @@ depends() {
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fi
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if is_lvm2_thinp_dump_target; then
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- if dracut --list-modules | grep -q lvmthinpool-monitor; then
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+ if grep -q lvmthinpool-monitor <<< $(dracut --list-modules); then
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add_opt_module lvmthinpool-monitor
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else
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dwarning "Required lvmthinpool-monitor modules is missing! Please upgrade dracut >= 057."
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--
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2.40.1
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