[PATCH v2 1/3] common: helper to get value from ndctl list by key

[Xiong Zhou <xzhou@redhat.com>]

For some nvdimm DAX related tests, it's better to know
some details of devices being tested. Adding new prog
ndctl to manage nvdimms and jq to parse outputs.

Signed-off-by: Xiong Zhou <xzhou@redhat.com>
---

v2:
  use _require_command instead of running cmds

 common/config |  2 ++
 common/rc     | 19 +++++++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/common/config b/common/config
index 59041a3..dfdcb8e 100644
--- a/common/config
+++ b/common/config
@@ -212,6 +212,8 @@ export XZ_PROG="`set_prog_path xz`"
 export FLOCK_PROG="`set_prog_path flock`"
 export LDD_PROG="`set_prog_path ldd`"
 export TIMEOUT_PROG="`set_prog_path timeout`"
+export NDCTL_PROG="`set_prog_path ndctl`"
+export JQ_PROG="`set_prog_path jq`"
 
 # use 'udevadm settle' or 'udevsettle' to wait for lv to be settled.
 # newer systems have udevadm command but older systems like RHEL5 don't.
diff --git a/common/rc b/common/rc
index e1ab2c6..bc387cf 100644
--- a/common/rc
+++ b/common/rc
@@ -3148,6 +3148,25 @@ _require_chattr()
     rm -f $TEST_DIR/syscalltest.out
 }
 
+_require_ndctl()
+{
+	_require_command "$NDCTL_PROG" ndctl
+}
+
+_require_jq()
+{
+	_require_command "$JQ_PROG" jq
+}
+
+# $1 SCRATCH_DEV or TEST_DEV or other dev
+# $2 key
+_ndctl_get_pmem_key_value()
+{
+	$NDCTL_PROG list | \
+	  $JQ_PROG -r ".[] | \
+	  select(.blockdev == \"${1#/dev/}\") | .$2"
+}
+
 _get_total_inode()
 {
 	if [ -z "$1" ]; then
-- 
1.8.3.1