ESP8266: Improve error handling and partial sends

Author: michalpasztamobica

components/wifi/esp8266-driver/ESP8266/ESP8266.cpp

@@ -612,7 +612,7 @@ bool ESP8266::dns_lookup(const char *name, char *ip)
     return done;
 }
 
-nsapi_error_t ESP8266::send(int id, const void *data, uint32_t amount)
+nsapi_size_or_error_t ESP8266::send(int id, const void *data, uint32_t amount)
 {
     nsapi_error_t ret = NSAPI_ERROR_DEVICE_ERROR;
     unsigned int send_ack_retries = 3;
@@ -651,15 +651,21 @@ nsapi_error_t ESP8266::send(int id, const void *data, uint32_t amount)
                 goto RETRY;
             }
         }
+        // This means ESP8266 hasn't even started to receive data
         tr_debug("send(): Didn't get \">\"");
-        ret = NSAPI_ERROR_WOULD_BLOCK;
+        if (_sock_i[id].proto == NSAPI_TCP) {
+            ret = NSAPI_ERROR_WOULD_BLOCK;
+        } else if (_sock_i[id].proto == NSAPI_UDP) {
+            ret = NSAPI_ERROR_NO_MEMORY;
+        }
         goto END;
     }
     _ok_received = false;
     _parser.remove_oob("OK");
 
     if (_parser.write((char *)data, (int)amount) < 0) {
-        tr_debug("Failed to write data");
+        tr_debug("Failed to write serial data");
+        // Serial is not working, serious error, reset needed.
         ret = NSAPI_ERROR_DEVICE_ERROR;
         goto END;
     }
@@ -669,6 +675,11 @@ nsapi_error_t ESP8266::send(int id, const void *data, uint32_t amount)
     if (!_parser.recv("Recv %d bytes", &bytes_confirmed)) {
         tr_debug("Bytes not confirmed.");
         ret = NSAPI_ERROR_DEVICE_ERROR;
+        if (_sock_i[id].proto == NSAPI_TCP) {
+            ret = NSAPI_ERROR_WOULD_BLOCK;
+        } else if (_sock_i[id].proto == NSAPI_UDP) {
+            ret = NSAPI_ERROR_NO_MEMORY;
+        }
         goto END;
     } else if (bytes_confirmed != amount) {
         tr_debug("Error: confirmed %d bytes, but expected %d.", bytes_confirmed, amount);
@@ -689,7 +700,7 @@ nsapi_error_t ESP8266::send(int id, const void *data, uint32_t amount)
             goto RETRY_SEND_ACK;
         }
     } else {
-        ret = NSAPI_ERROR_OK;
+        ret = amount;
     }
 
 END:
@@ -711,9 +722,9 @@ nsapi_error_t ESP8266::send(int id, const void *data, uint32_t amount)
         tr_debug("send(): Connection disrupted.");
     }
 
-    if (!_sock_i[id].open && ret != NSAPI_ERROR_OK) {
+    if (!_sock_i[id].open && ret < NSAPI_ERROR_OK) {
         ret = NSAPI_ERROR_CONNECTION_LOST;
-        tr_debug("send(): Socket closed abruptly.");
+        tr_debug("send(): Socket %d closed abruptly.", id);
     }
 
     set_timeout();

components/wifi/esp8266-driver/ESP8266/ESP8266.h

@@ -255,10 +255,10 @@ class ESP8266 {
     *
     * @param id id of socket to send to
     * @param data data to be sent
-    * @param amount amount of data to be sent - max 1024
-    * @return NSAPI_ERROR_OK in success, negative error code in failure
+    * @param amount amount of data to be sent - max 2048
+    * @return number of bytes on success, negative error code in failure
     */
-    nsapi_error_t send(int id, const void *data, uint32_t amount);
+    nsapi_size_or_error_t send(int id, const void *data, uint32_t amount);
 
     /**
     * Receives datagram from an open UDP socket

components/wifi/esp8266-driver/ESP8266Interface.cpp

@@ -849,7 +849,7 @@ int ESP8266Interface::socket_accept(void *server, void **socket, SocketAddress *
 
 int ESP8266Interface::socket_send(void *handle, const void *data, unsigned size)
 {
-    nsapi_error_t status;
+    nsapi_size_or_error_t status;
     struct esp8266_socket *socket = (struct esp8266_socket *)handle;
     uint8_t expect_false = false;
 
@@ -881,7 +881,7 @@ int ESP8266Interface::socket_send(void *handle, const void *data, unsigned size)
         status = NSAPI_ERROR_DEVICE_ERROR;
     }
 
-    return status != NSAPI_ERROR_OK ? status : size;
+    return status;
 }
 
 int ESP8266Interface::socket_recv(void *handle, void *data, unsigned size)