unit tests: prepare for kdumpctl and kdump-lib.sh to be unit-tested

Currently there are two issues with unit-testing the functions defined
in kdumpctl and other shell scripts after sourcing them,
  - kdumpctl would call main which requires root permission and would
    create single instance lock (/var/lock/kdump)
  - kdumpctl and other shell scripts directly source files under /usr/lib/kdump/

When ShellSpec load a script via "Include", it defines the__SOURCED__
variable. By making use of __SOURCED__, we can
1. let kdumpctl not call main when kdumpctl is "Include"d by ShellSpec
2. instruct kdumpctl and kdump-lib.sh to source the files in the repo
   when running ShelSpec tests

Note coverage/ is added to .gitignore because ShellSpec generates code
coverage results in this folder.

Reviewed-by: Philipp Rudo <prudo@redhat.com>
Signed-off-by: Coiby Xu <coxu@redhat.com>

.gitignore

@@ -21,3 +21,4 @@
 /kexec-tools-2.0.11.tar.xz
 /makedumpfile-1.5.9.tar.gz
 /kexec-tools-2.0.12.tar.xz
+coverage/

kdump-lib.sh

@@ -2,8 +2,11 @@
 #
 # Kdump common variables and functions
 #
-
+if [[ ${__SOURCED__:+x} ]]; then
-. /usr/lib/kdump/kdump-lib-initramfs.sh
+	. ./kdump-lib-initramfs.sh
+else
+	. /lib/kdump/kdump-lib-initramfs.sh
+fi
 
 FADUMP_ENABLED_SYS_NODE="/sys/kernel/fadump_enabled"
 

kdumpctl

@@ -32,8 +32,14 @@ fi
 
 [[ $dracutbasedir ]] || dracutbasedir=/usr/lib/dracut
 . $dracutbasedir/dracut-functions.sh
-. /lib/kdump/kdump-lib.sh
+
-. /lib/kdump/kdump-logger.sh
+if [[ ${__SOURCED__:+x} ]]; then
+	KDUMP_LIB_PATH=.
+else
+	KDUMP_LIB_PATH=/lib/kdump
+fi
+. $KDUMP_LIB_PATH/kdump-lib.sh
+. $KDUMP_LIB_PATH/kdump-logger.sh
 
 #initiate the kdump logger
 if ! dlog_init; then
@@ -1676,11 +1682,6 @@ reset_crashkernel_for_installed_kernel()
 	fi
 }
 
-if [[ ! -f $KDUMP_CONFIG_FILE ]]; then
-	derror "Error: No kdump config file found!"
-	exit 1
-fi
-
 main()
 {
 	# Determine if the dump mode is kdump or fadump
@@ -1753,6 +1754,15 @@ main()
 	esac
 }
 
+if [[ ${__SOURCED__:+x} ]]; then
+	return
+fi
+
+if [[ ! -f $KDUMP_CONFIG_FILE ]]; then
+	derror "Error: No kdump config file found!"
+	exit 1
+fi
+
 # Other kdumpctl instances will block in queue, until this one exits
 single_instance_lock