Peer review fixes

Author: dgarske

src/port/rtl8735b/main.c

@@ -96,6 +96,7 @@ static void echo_cb(int fd, uint16_t event, void *arg)
 {
     struct wolfIP *s = (struct wolfIP *)arg;
     int ret;
+    int sent;
 
     if ((fd == listen_fd) && (event & CB_EVENT_READABLE) && (client_fd == -1)) {
         int c = wolfIP_sock_accept(s, listen_fd, NULL, NULL);
@@ -112,9 +113,15 @@ static void echo_cb(int fd, uint16_t event, void *arg)
         do {
             ret = wolfIP_sock_recvfrom(s, client_fd, rx_buf, sizeof(rx_buf), 0,
                                        NULL, NULL);
-            if (ret > 0)
-                (void)wolfIP_sock_sendto(s, client_fd, rx_buf, (uint32_t)ret, 0,
-                                         NULL, 0);
+            if (ret > 0) {
+                /* Demo echo: no TX backpressure buffering. If the TX buffer
+                 * is full (EAGAIN) or the write is short, the excess is
+                 * dropped; log it so the drop is visible instead of silent. */
+                sent = wolfIP_sock_sendto(s, client_fd, rx_buf, (uint32_t)ret,
+                                          0, NULL, 0);
+                if (sent != ret)
+                    printf("echo: TX drop (sent=%d of %d)\r\n", sent, ret);
+            }
         } while (ret > 0);
         if (ret == 0) {
             wolfIP_sock_close(s, client_fd);

src/port/rtl8735b/tls_client.c

@@ -92,10 +92,17 @@ static void tls_client_teardown(void)
     }
 }
 
-/* Enter a terminal state (DONE/ERROR), freeing the SSL object first. */
+/* Enter a terminal state (DONE/ERROR): free the SSL object and release the
+ * socket so the fd is not orphaned if the caller never calls
+ * tls_client_close(). tls_client_close() then guards on fd >= 0, so its own
+ * close becomes a safe no-op. */
 static void tls_client_finish(tls_client_state_t st)
 {
     tls_client_teardown();
+    if (client.fd >= 0 && client.stack) {
+        wolfIP_sock_close(client.stack, client.fd);
+        client.fd = -1;
+    }
     client.state = st;
 }
 

src/port/rtl8735b/wolfip_eth.cmake

@@ -31,7 +31,7 @@ set(WOLFIP_PORT_DIR ${WOLFIP_ROOT}/src/port/rtl8735b)
 ### ---- header search paths (example dir first so our config.h wins) ---- ###
 list(APPEND app_example_inc_path
     ${CMAKE_CURRENT_LIST_DIR}     # user_settings.h (this example dir)
-    ${WOLFIP_PORT_DIR}            # config.h, rtl8735b_eth.h, tls_client.h
+    ${WOLFIP_PORT_DIR}            # config.h, wolfip_rtl8735b.h, tls_client.h
     ${WOLFIP_ROOT}               # wolfip.h
 )
 

src/port/rtl8735b/wolfip_rtl8735b.c

@@ -189,6 +189,9 @@ int rtl8735b_eth_init(struct wolfIP_ll_dev *ll, const uint8_t *mac)
     if (ll == NULL)
         return -1;
 
+    /* Release any buffers from a prior init so a re-init does not leak. */
+    free_eth_bufs();
+
     /* Descriptor rings in reserved SRAM: TX first, RX right after. */
     tx_desc = (uint8_t *)__sram_rev_start__;
     rx_desc = tx_desc + (RTL8735B_TX_DESC_NO * ETH_TX_DESC_SIZE);