From 3d2079c31cd80741ea6d44eb7f13d7f08be74a94 Mon Sep 17 00:00:00 2001
From: Coiby Xu <coxu@redhat.com>
Date: Wed, 1 Dec 2021 16:57:15 +0800
Subject: [PATCH] add helper functions to get dump mode

Add a helper function to get dump mode. The dump mode would be
 - fadump if fadump=on or fadump=nocma
 - kdump if fadump=off or empty fadump

Otherwise return 1.

Also add another helper function to return a kernel's dump mode.

Reviewed-by: Pingfan Liu <piliu@redhat.com>
Reviewed-by: Philipp Rudo <prudo@redhat.com>
Signed-off-by: Coiby Xu <coxu@redhat.com>
---
 kdumpctl | 34 ++++++++++++++++++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/kdumpctl b/kdumpctl
index 6f6bdd2..a72b71b 100755
--- a/kdumpctl
+++ b/kdumpctl
@@ -1291,6 +1291,40 @@ get_grub_kernel_boot_parameter()
 	grubby --info="$_kernel_path" | sed -En -e "/^args=.*$/{s/^.*(\s|\")${_para}=(\S*).*\"$/\2/p;q}"
 }
 
+# get dump mode by fadump value
+# return
+#  - fadump, if fadump=on or fadump=nocma
+#  - kdump, if fadump=off or empty fadump, return kdump
+#  - error if otherwise
+get_dump_mode_by_fadump_val()
+{
+	local _fadump_val=$1
+
+	if [[ -z $_fadump_val ]] || [[ $_fadump_val == off ]]; then
+		echo -n kdump
+	elif [[ $_fadump_val == on ]] || [[ $_fadump_val == nocma ]]; then
+		echo -n fadump
+	else
+		derror "invalid fadump=$_fadump_val"
+		return 1
+	fi
+}
+
+# get dump mode of a specific kernel
+# based on its fadump kernel cmdline parameter
+get_dump_mode_by_kernel()
+{
+	local _kernel_path=$1 _fadump_val _dump_mode
+
+	_fadump_val=$(get_grub_kernel_boot_parameter "$_kernel_path" fadump)
+	if _dump_mode=$(get_dump_mode_by_fadump_val "$_fadump_val"); then
+		echo -n "$_dump_mode"
+	else
+		derror "failed to get dump mode for kernel $_kernel_path"
+		exit
+	fi
+}
+
 reset_crashkernel()
 {
 	local kernel=$1 entry crashkernel_default