[monitoring-plugins] Fix some minor compiler warnings

[Lorenz Kästle]

 Module: monitoring-plugins
 Branch: master
 Commit: c1384375bc55c41bc79a1e1bcce57ffee263b52d
 Author: Lorenz Kästle <12514511+RincewindsHat at users.noreply.github.com>
   Date: Fri Jan  9 13:05:25 2026 +0100
    URL: https://www.monitoring-plugins.org/repositories/monitoring-plugins/commit/?id=c1384375

Fix some minor compiler warnings

---

 plugins/check_snmp.d/check_snmp_helpers.c | 10 ++++++----
 plugins/check_snmp.d/check_snmp_helpers.h |  4 ++--
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/plugins/check_snmp.d/check_snmp_helpers.c b/plugins/check_snmp.d/check_snmp_helpers.c
index f506537a..2dfc88b5 100644
--- a/plugins/check_snmp.d/check_snmp_helpers.c
+++ b/plugins/check_snmp.d/check_snmp_helpers.c
@@ -36,7 +36,8 @@ int check_snmp_set_thresholds(const char *threshold_string, check_snmp_test_unit
 			threshold_string++;
 		}
 
-		for (char *ptr = strtok(threshold_string, ", "); ptr != NULL;
+		char *thr_string_copy = strdup(threshold_string);
+		for (char *ptr = strtok(thr_string_copy, ", "); ptr != NULL;
 			 ptr = strtok(NULL, ", "), tu_index++) {
 
 			if (tu_index > max_test_units) {
@@ -64,6 +65,7 @@ int check_snmp_set_thresholds(const char *threshold_string, check_snmp_test_unit
 			}
 		}
 
+		free(thr_string_copy);
 	} else {
 		// Single value
 		// only valid for the first test unit
@@ -843,8 +845,8 @@ char *_np_state_calculate_location_prefix(void) {
  * Sets variables. Generates filename. Returns np_state_key. die with
  * UNKNOWN if exception
  */
-state_key np_enable_state(char *keyname, int expected_data_version, char *plugin_name, int argc,
-						  char **argv) {
+state_key np_enable_state(char *keyname, int expected_data_version, const char *plugin_name,
+						  int argc, char **argv) {
 	state_key *this_state = (state_key *)calloc(1, sizeof(state_key));
 	if (this_state == NULL) {
 		die(STATE_UNKNOWN, _("Cannot allocate memory: %s"), strerror(errno));
@@ -869,7 +871,7 @@ state_key np_enable_state(char *keyname, int expected_data_version, char *plugin
 		tmp_char++;
 	}
 	this_state->name = temp_keyname;
-	this_state->plugin_name = plugin_name;
+	this_state->plugin_name = (char *)plugin_name;
 	this_state->data_version = expected_data_version;
 	this_state->state_data = NULL;
 
diff --git a/plugins/check_snmp.d/check_snmp_helpers.h b/plugins/check_snmp.d/check_snmp_helpers.h
index 0f7780b1..95b361ac 100644
--- a/plugins/check_snmp.d/check_snmp_helpers.h
+++ b/plugins/check_snmp.d/check_snmp_helpers.h
@@ -66,6 +66,6 @@ typedef struct state_key_struct {
 } state_key;
 
 state_data *np_state_read(state_key stateKey);
-state_key np_enable_state(char *keyname, int expected_data_version, char *plugin_name, int argc,
-						  char **argv);
+state_key np_enable_state(char *keyname, int expected_data_version, const char *plugin_name,
+						  int argc, char **argv);
 void np_state_write_string(state_key stateKey, time_t timestamp, char *stringToStore);