extmod/modlwip: Consolidate socket.accept timeout logic.

This makes the code a bit simpler to understand for the three cases of
timeout behaviour (-1, 0, non-zero), and eliminates a dependency on the
(slow) `mp_hal_delay_ms(100)` call.

Signed-off-by: Damien George <damien@micropython.org>

1 files changed, 12 insertions, 16 deletions

diff --git a/extmod/modlwip.c b/extmod/modlwip.c
index 1ae8c114c..bcee3f0ff 100644
--- a/extmod/modlwip.c
+++ b/extmod/modlwip.c
@@ -1040,26 +1040,22 @@ static mp_obj_t lwip_socket_accept(mp_obj_t self_in) {
     // accept incoming connection
     struct tcp_pcb *volatile *incoming_connection = &lwip_socket_incoming_array(socket)[socket->incoming.connection.iget];
     if (*incoming_connection == NULL) {
-        if (socket->timeout == 0) {
+        mp_uint_t ticks_start = mp_hal_ticks_ms();
+        for (;;) {
             MICROPY_PY_LWIP_EXIT
-            m_del_obj(lwip_socket_obj_t, socket2);
-            mp_raise_OSError(MP_EAGAIN);
-        } else if (socket->timeout != -1) {
-            mp_uint_t retries = socket->timeout / 100;
-            while (*incoming_connection == NULL) {
+            poll_sockets();
+            MICROPY_PY_LWIP_REENTER
+            if (*incoming_connection != NULL) {
+                break;
+            }
+            if (socket_is_timedout(socket, ticks_start)) {
                 MICROPY_PY_LWIP_EXIT
-                if (retries-- == 0) {
-                    m_del_obj(lwip_socket_obj_t, socket2);
+                m_del_obj(lwip_socket_obj_t, socket2);
+                if (socket->timeout == 0) {
+                    mp_raise_OSError(MP_EAGAIN);
+                } else {
                     mp_raise_OSError(MP_ETIMEDOUT);
                 }
-                mp_hal_delay_ms(100);
-                MICROPY_PY_LWIP_REENTER
-            }
-        } else {
-            while (*incoming_connection == NULL) {
-                MICROPY_PY_LWIP_EXIT
-                poll_sockets();
-                MICROPY_PY_LWIP_REENTER
             }
         }
     }