PPP: removed ppp_delete(), merged with ppp_free()

The only benefit of ppp_delete() call was about having a persistent
netif interface. netif was moved out of PPP pcb so we don't need
ppp_delete() anymore, second step in simplifying the weird
new/open/free/delete PPP API.

src/api/pppapi.c

@@ -308,24 +308,24 @@ pppapi_sighup(ppp_pcb *pcb)
 
 
 /**
- * Call ppp_delete() inside the tcpip_thread context.
+ * Call ppp_free() inside the tcpip_thread context.
  */
 static void
-pppapi_do_ppp_delete(struct pppapi_msg_msg *msg)
+pppapi_do_ppp_free(struct pppapi_msg_msg *msg)
 {
-  msg->err = ppp_delete(msg->ppp);
+  msg->err = ppp_free(msg->ppp);
   TCPIP_PPPAPI_ACK(msg);
 }
 
 /**
- * Call ppp_delete() in a thread-safe way by running that function inside the
+ * Call ppp_free() in a thread-safe way by running that function inside the
  * tcpip_thread context.
  */
 int
-pppapi_delete(ppp_pcb *pcb)
+pppapi_free(ppp_pcb *pcb)
 {
   struct pppapi_msg msg;
-  msg.function = pppapi_do_ppp_delete;
+  msg.function = pppapi_do_ppp_free;
   msg.msg.ppp = pcb;
   TCPIP_PPPAPI(&msg);
   return msg.msg.err;

src/include/lwip/pppapi.h

@@ -136,7 +136,7 @@ ppp_pcb *pppapi_over_l2tp_create(struct netif *pppif, struct netif *netif, ip_ad
 int pppapi_open(ppp_pcb *pcb, u16_t holdoff);
 int pppapi_close(ppp_pcb *pcb);
 void pppapi_sighup(ppp_pcb *pcb);
-int pppapi_delete(ppp_pcb *pcb);
+int pppapi_free(ppp_pcb *pcb);
 int pppapi_ioctl(ppp_pcb *pcb, int cmd, void *arg);
 #if LWIP_NETIF_STATUS_CALLBACK
 void pppapi_set_netif_statuscallback(ppp_pcb *pcb, netif_status_callback_fn status_callback);

src/include/netif/ppp/ppp.h

@@ -573,21 +573,6 @@ int ppp_close(ppp_pcb *pcb);
  */
 void ppp_sighup(ppp_pcb *pcb);
 
-/*
- * Free the control block, clean everything except the PPP PCB itself
- * and the netif, it allows you to change the underlying PPP protocol
- * (eg. from PPPoE to PPPoS to switch from DSL to GPRS) without losing
- * your PPP and netif handlers.
- *
- * This can only be called if PPP is in the dead phase.
- *
- * You must use ppp_close() before if you wish to terminate
- * an established PPP session.
- *
- * Return 0 on success, an error code on failure.
- */
-int ppp_free(ppp_pcb *pcb);
-
 /*
  * Release the control block.
  *
@@ -598,7 +583,7 @@ int ppp_free(ppp_pcb *pcb);
  *
  * Return 0 on success, an error code on failure.
  */
-int ppp_delete(ppp_pcb *pcb);
+int ppp_free(ppp_pcb *pcb);
 
 /*
  * Get and set parameters for the given connection.

src/netif/ppp/ppp.c

@@ -352,7 +352,7 @@ ppp_pcb *ppp_over_ethernet_create(struct netif *pppif, struct netif *ethif, cons
   pcb->ctx_cb = ctx_cb;
 
   if (pppoe_create(ethif, pcb, ppp_over_ethernet_link_status_cb, &pcb->pppoe_sc) != ERR_OK) {
-    ppp_delete(pcb);
+    ppp_free(pcb);
     return NULL;
   }
 
@@ -383,7 +383,7 @@ ppp_pcb *ppp_over_l2tp_create(struct netif *pppif, struct netif *netif, ip_addr_
   pcb->ctx_cb = ctx_cb;
 
   if (pppol2tp_create(pcb, ppp_over_l2tp_link_status_cb, &pcb->l2tp_pcb, netif, ipaddr, port, secret, secret_len) != ERR_OK) {
-    ppp_delete(pcb);
+    ppp_free(pcb);
     return NULL;
   }
 
@@ -478,10 +478,7 @@ ppp_sighup(ppp_pcb *pcb)
 }
 
 /*
- * Free the control block, clean everything except the PPP PCB itself
+ * Release the control block.
- * and the netif, it allows you to change the underlying PPP protocol
- * (eg. from PPPoE to PPPoS to switch from DSL to GPRS) without losing
- * your PPP and netif handlers.
  *
  * This can only be called if PPP is in the dead phase.
  *
@@ -497,6 +494,8 @@ int ppp_free(ppp_pcb *pcb) {
 
   PPPDEBUG(LOG_DEBUG, ("ppp_free: unit %d\n", pcb->num));
 
+  netif_remove(pcb->netif);
+
 #if PPPOE_SUPPORT
   if (pcb->pppoe_sc) {
     pppoe_destroy(pcb->pppoe_sc);
@@ -516,33 +515,6 @@ int ppp_free(ppp_pcb *pcb) {
   ppp_free_current_input_packet(&pcb->rx);
 #endif /* PPPOS_SUPPORT */
 
-  return 0;
-}
-
-/*
- * Release the control block.
- *
- * This can only be called if PPP is in the dead phase.
- *
- * You must use ppp_close() before if you wish to terminate
- * an established PPP session.
- *
- * Return 0 on success, an error code on failure.
- */
-int ppp_delete(ppp_pcb *pcb) {
-  int err;
-
-  if (pcb->phase != PPP_PHASE_DEAD) {
-    return PPPERR_PARAM;
-  }
-
-  PPPDEBUG(LOG_DEBUG, ("ppp_delete: unit %d\n", pcb->num));
-
-  netif_remove(pcb->netif);
-  if( (err = ppp_free(pcb)) != PPPERR_NONE) {
-    return err;
-  }
-
   memp_free(MEMP_PPP_PCB, pcb);
   return 0;
 }