sd-dhcp: refactor dhcp_option_append

Store a pointer to the options in the DHCPMessage struct, and pass
this together with an offset around, rather than a uint8_t**.

This avoids us having to (re)compute the pointer; and changes
dhcp_option_append from adjusting both the pointer to the next
option and the remaining size of the options, to just adjusting
the current offset.

This makes the code a bit simpler to follow IMHO, but there should
be no functional change.

1 files changed, 3 insertions, 3 deletions

diff --git a/src/libsystemd-network/dhcp-internal.h b/src/libsystemd-network/dhcp-internal.h
index eb4a6cdce2..56423a2cce 100644
--- a/src/libsystemd-network/dhcp-internal.h
+++ b/src/libsystemd-network/dhcp-internal.h
@@ -36,8 +36,8 @@ int dhcp_network_send_raw_socket(int s, const union sockaddr_union *link,
 int dhcp_network_send_udp_socket(int s, be32_t address, uint16_t port,
                                  const void *packet, size_t len);
 
-int dhcp_option_append(uint8_t **buf, size_t *buflen, uint8_t code,
-                       size_t optlen, const void *optval);
+int dhcp_option_append(uint8_t options[], size_t size, size_t *offset,
+                       uint8_t code, size_t optlen, const void *optval);
 
 typedef int (*dhcp_option_cb_t)(uint8_t code, uint8_t len,
                                 const uint8_t *option, void *user_data);
@@ -46,7 +46,7 @@ int dhcp_option_parse(DHCPMessage *message, size_t len,
                       dhcp_option_cb_t cb, void *user_data);
 
 int dhcp_message_init(DHCPMessage *message, uint8_t op, uint32_t xid, uint8_t type,
-                      uint8_t **opt, size_t *optlen);
+                      uint8_t options[], size_t optlen, size_t *optoffset);
 
 uint16_t dhcp_packet_checksum(void *buf, size_t len);