From ebe2184e2a4f277baabcf1d3cde6619a5b3c5d46 Mon Sep 17 00:00:00 2001
From: Juraj Andrassy <juraj.andrassy@gmail.com>
Date: Wed, 13 Dec 2023 22:00:01 +0100
Subject: [PATCH] lwipClient - fix mem pool leak with shared_ptr

---
 libraries/lwIpWrapper/src/lwipClient.cpp | 14 ++++++++------
 libraries/lwIpWrapper/src/lwipClient.h   |  3 ++-
 2 files changed, 10 insertions(+), 7 deletions(-)

diff --git a/libraries/lwIpWrapper/src/lwipClient.cpp b/libraries/lwIpWrapper/src/lwipClient.cpp
index 8facb252..4109306a 100644
--- a/libraries/lwIpWrapper/src/lwipClient.cpp
+++ b/libraries/lwIpWrapper/src/lwipClient.cpp
@@ -8,7 +8,6 @@ extern "C" {
 
 /* -------------------------------------------------------------------------- */
 lwipClient::lwipClient()
-    : _tcp_client(NULL)
 {
 }
 /* -------------------------------------------------------------------------- */
@@ -17,7 +16,6 @@ lwipClient::lwipClient()
 sketches but sock is ignored. */
 /* -------------------------------------------------------------------------- */
 lwipClient::lwipClient(uint8_t sock)
-    : _tcp_client(NULL)
 {
 }
 /* -------------------------------------------------------------------------- */
@@ -25,7 +23,10 @@ lwipClient::lwipClient(uint8_t sock)
 /* -------------------------------------------------------------------------- */
 lwipClient::lwipClient(struct tcp_struct* tcpClient)
 {
-    _tcp_client = tcpClient;
+    if (tcpClient == NULL)
+        return;
+    _tcp_client.reset(tcpClient,
+            [](struct tcp_struct *tcp_client) { (void) tcp_client; } ); // empty deleter
 }
 /* -------------------------------------------------------------------------- */
 
@@ -49,7 +50,8 @@ int lwipClient::connect(IPAddress ip, uint16_t port)
     /* -------------------------------------------------------------------------- */
     if (_tcp_client == NULL) {
         /* Allocates memory for client */
-        _tcp_client = (struct tcp_struct*)mem_malloc(sizeof(struct tcp_struct));
+        _tcp_client.reset((struct tcp_struct*)mem_malloc(sizeof(struct tcp_struct)),
+                [](struct tcp_struct *tcp_client) { mem_free(tcp_client); } );
 
         if (_tcp_client == NULL) {
             return 0;
@@ -69,7 +71,7 @@ int lwipClient::connect(IPAddress ip, uint16_t port)
 
     uint32_t startTime = millis();
     ip_addr_t ipaddr;
-    tcp_arg(_tcp_client->pcb, _tcp_client);
+    tcp_arg(_tcp_client->pcb, _tcp_client.get());
     if (ERR_OK != tcp_connect(_tcp_client->pcb, u8_to_ip_addr(rawIPAddress(ip), &ipaddr), port, &tcp_connected_callback)) {
         stop();
         return 0;
@@ -215,7 +217,7 @@ void lwipClient::stop()
 
     // close tcp connection if not closed yet
     if (status() != TCP_CLOSING) {
-        tcp_connection_close(_tcp_client->pcb, _tcp_client);
+        tcp_connection_close(_tcp_client->pcb, _tcp_client.get());
     }
 }
 
diff --git a/libraries/lwIpWrapper/src/lwipClient.h b/libraries/lwIpWrapper/src/lwipClient.h
index 511b3c7f..0dc282d3 100644
--- a/libraries/lwIpWrapper/src/lwipClient.h
+++ b/libraries/lwIpWrapper/src/lwipClient.h
@@ -9,6 +9,7 @@
 #include "lwipMem.h"
 #include "lwipTcp.h"
 #include "lwipTypes.h"
+#include <memory>
 
 class lwipClient : public Client {
 
@@ -66,7 +67,7 @@ class lwipClient : public Client {
     using Print::write;
 
 private:
-    struct tcp_struct* _tcp_client;
+    std::shared_ptr<struct tcp_struct> _tcp_client;
     uint16_t _timeout = 10000;
 };