nvme: allow to overwrite hostnqn and hostid

In order to be able to test the topology scan code, allow
hostnqn and hostid to be controlled via an environment variable.

This is just for testing purposes, thus don't mention it.

Signed-off-by: Daniel Wagner <[email protected]>

Author: dwsuse

src/nvme/fabrics.c

@@ -1416,11 +1416,21 @@ static char *nvmf_read_file(const char *f, int len)
 
 char *nvmf_hostnqn_from_file()
 {
+	char *hostnqn = getenv("LIBNVME_HOSTNQN");
+
+	if (hostnqn)
+		return strdup(hostnqn);
+
 	return nvmf_read_file(NVMF_HOSTNQN_FILE, NVMF_NQN_SIZE);
 }
 
 char *nvmf_hostid_from_file()
 {
+	char *hostid = getenv("LIBNVME_HOSTID");
+
+	if (hostid)
+		return strdup(hostid);
+
 	return nvmf_read_file(NVMF_HOSTID_FILE, NVMF_HOSTID_SIZE);
 }