[DHCP] Optimize the DHCP startup logic

1 files changed, 15 insertions, 6 deletions

diff --git a/components/net/lwip-dhcpd/dhcp_server_raw.c b/components/net/lwip-dhcpd/dhcp_server_raw.c
index b271ce36b9..2e18966151 100644
--- a/components/net/lwip-dhcpd/dhcp_server_raw.c
+++ b/components/net/lwip-dhcpd/dhcp_server_raw.c
@@ -577,7 +577,6 @@ dhcp_server_recv(void *arg, struct udp_pcb *pcb, struct pbuf *p, const ip_addr_t
                             break;
                         }
                         node_prev = node;
-                        node = node->next;
                     }
 
                     if (node != NULL)
@@ -615,6 +614,7 @@ err_t
 dhcp_server_start(struct netif *netif, ip4_addr_t *start, ip4_addr_t *end)
 {
     struct dhcp_server *dhcp_server;
+    err_t err;
 
     /* If this netif alreday use the dhcp server. */
     for (dhcp_server = lw_dhcp_server; dhcp_server != NULL; dhcp_server = dhcp_server->next)
@@ -640,9 +640,6 @@ dhcp_server_start(struct netif *netif, ip4_addr_t *start, ip4_addr_t *end)
     /* clear data structure */
     memset(dhcp_server, 0, sizeof(struct dhcp_server));
 
-    /* store this dhcp server to list */
-    dhcp_server->next = lw_dhcp_server;
-    lw_dhcp_server = dhcp_server;
     dhcp_server->netif = netif;
     dhcp_server->node_list = NULL;
     dhcp_server->start = *start;
@@ -654,15 +651,27 @@ dhcp_server_start(struct netif *netif, ip4_addr_t *start, ip4_addr_t *end)
     if (dhcp_server->pcb == NULL)
     {
         LWIP_DEBUGF(DHCP_DEBUG  | LWIP_DBG_TRACE, ("dhcp_server_start(): could not obtain pcb\n"));
+        mem_free(dhcp_server);
         return ERR_MEM;
     }
 
     ip_set_option(dhcp_server->pcb, SOF_BROADCAST);
     /* set up local and remote port for the pcb */
-    udp_bind(dhcp_server->pcb, IP_ADDR_ANY, DHCP_SERVER_PORT);
+    err = udp_bind(dhcp_server->pcb, IP_ADDR_ANY, DHCP_SERVER_PORT);
+    if (err != ERR_OK)
+    {
+        LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_server_start(): could not bind pcb, err=%d\n", (int)err));
+        udp_remove(dhcp_server->pcb);
+        mem_free(dhcp_server);
+        return err;
+    }
     //udp_connect(dhcp_server->pcb, IP_ADDR_ANY, DHCP_CLIENT_PORT);
     /* set up the recv callback and argument */
     udp_recv(dhcp_server->pcb, dhcp_server_recv, dhcp_server);
+
+    /* Publish the server only after all resources are ready. */
+    dhcp_server->next = lw_dhcp_server;
+    lw_dhcp_server = dhcp_server;
     LWIP_DEBUGF(DHCP_DEBUG | LWIP_DBG_TRACE, ("dhcp_server_start(): starting DHCP server\n"));
 
     return ERR_OK;
@@ -742,7 +751,7 @@ void dhcpd_start(const char *netif_name)
         res = dhcp_server_start(netif, &ip_start, &ip_end);
         if (res != 0)
         {
-            DEBUG_PRINTF("dhcp_server_start res: %s.\r\n", res);
+            DEBUG_PRINTF("dhcp_server_start res: %d.\r\n", (int)res);
         }
     }