From f04c991a2fbb3531c3b464ed8e6dd7543e521f7a Mon Sep 17 00:00:00 2001
From: Yu Watanabe <watanabe.yu+github@gmail.com>
Date: Tue, 9 May 2023 00:34:06 +0900
Subject: [PATCH] sd-dhcp-client: make return arguments for
 sd_dhcp_client_get_client_id() optional

---
 src/libsystemd-network/sd-dhcp-client.c | 35 +++++++++++++++----------
 src/systemd/sd-dhcp-client.h            |  6 ++---
 2 files changed, 24 insertions(+), 17 deletions(-)

diff --git a/src/libsystemd-network/sd-dhcp-client.c b/src/libsystemd-network/sd-dhcp-client.c
index b73abcb82d..19ed80db5c 100644
--- a/src/libsystemd-network/sd-dhcp-client.c
+++ b/src/libsystemd-network/sd-dhcp-client.c
@@ -339,25 +339,32 @@ int sd_dhcp_client_set_mac(
 
 int sd_dhcp_client_get_client_id(
                 sd_dhcp_client *client,
-                uint8_t *type,
-                const uint8_t **data,
-                size_t *data_len) {
+                uint8_t *ret_type,
+                const uint8_t **ret_data,
+                size_t *ret_data_len) {
 
         assert_return(client, -EINVAL);
-        assert_return(type, -EINVAL);
-        assert_return(data, -EINVAL);
-        assert_return(data_len, -EINVAL);
 
-        if (client->client_id_len) {
-                *type = client->client_id.type;
-                *data = client->client_id.raw.data;
-                *data_len = client->client_id_len - sizeof(client->client_id.type);
-        } else {
-                *type = 0;
-                *data = NULL;
-                *data_len = 0;
+        if (client->client_id_len > 0) {
+                if (client->client_id_len < offsetof(sd_dhcp_client_id, raw.data))
+                        return -EINVAL;
+
+                if (ret_type)
+                        *ret_type = client->client_id.type;
+                if (ret_data)
+                        *ret_data = client->client_id.raw.data;
+                if (ret_data_len)
+                        *ret_data_len = client->client_id_len - offsetof(sd_dhcp_client_id, raw.data);
+                return 1;
         }
 
+        if (ret_type)
+                *ret_type = 0;
+        if (ret_data)
+                *ret_data = NULL;
+        if (ret_data_len)
+                *ret_data_len = 0;
+
         return 0;
 }
 
diff --git a/src/systemd/sd-dhcp-client.h b/src/systemd/sd-dhcp-client.h
index 2b3f995769..2b8fddcf04 100644
--- a/src/systemd/sd-dhcp-client.h
+++ b/src/systemd/sd-dhcp-client.h
@@ -279,9 +279,9 @@ int sd_dhcp_client_set_duid_llt(
                 uint64_t llt_time);
 int sd_dhcp_client_get_client_id(
                 sd_dhcp_client *client,
-                uint8_t *type,
-                const uint8_t **data,
-                size_t *data_len);
+                uint8_t *ret_type,
+                const uint8_t **ret_data,
+                size_t *ret_data_len);
 int sd_dhcp_client_set_mtu(
                 sd_dhcp_client *client,
                 uint32_t mtu);