Refactor ESP8266WiFiMulti to use esp_delay. Optimisation opportunity: don't thrash the recurrent functions scheduler by using intvl_ms != 0. Keeping the MCU out of the idle task increases power consumption.

Author: dok-net

libraries/ESP8266WiFi/src/ESP8266WiFiGeneric.cpp

@@ -434,6 +434,8 @@ bool ESP8266WiFiGenericClass::mode(WiFiMode_t m) {
     //tasks to wait correctly.
     constexpr unsigned int timeoutValue = 1000; //1 second
     if(can_yield()) {
+        // The final argument, intvl_ms, to esp_delay influences how frequently
+        // the scheduled recurrent functions (Schedule.h) are probed.
         esp_delay(timeoutValue, [m]() { return wifi_get_opmode() != m; }, 5);
 
         //if at this point mode still hasn't been reached, give up

libraries/ESP8266WiFi/src/ESP8266WiFiMulti.cpp

@@ -27,6 +27,7 @@
 #include "ESP8266WiFiMulti.h"
 #include <limits.h>
 #include <string.h>
+#include <coredecls.h>
 
 /**
  * @brief Print WiFi status
@@ -83,36 +84,25 @@ static void printWiFiStatus(wl_status_t status)
 static wl_status_t waitWiFiConnect(uint32_t connectTimeoutMs)
 {
     wl_status_t status;
+    // The final argument, intvl_ms, to esp_delay influences how frequently
+    // the scheduled recurrent functions (Schedule.h) are probed.
+    esp_delay(connectTimeoutMs,
+        [&status]() { status = WiFi.status(); return status != WL_CONNECTED && status != WL_CONNECT_FAILED; }, 0);
 
-    // Set WiFi connect timeout
-    using esp8266::polledTimeout::oneShotMs;
-    oneShotMs connectTimeout(connectTimeoutMs);
-
-    // Wait for WiFi status change or timeout
-    do {
-        // Refresh watchdog
-        delay(0);
-
-        // Get WiFi status
-        status = WiFi.status();
-
-        // Check status
-        if (status == WL_CONNECTED) {
-            // Connected, print WiFi status
-            printWiFiStatus(status);
-
-            // Return WiFi status
-            return status;
-        } else if (status == WL_CONNECT_FAILED) {
-            DEBUG_WIFI_MULTI("[WIFIM] Connect failed\n");
-
-            // Return WiFi connect failed
-            return WL_CONNECT_FAILED;
-        }
-    } while (!connectTimeout);
+    // Check status
+    if (status == WL_CONNECTED) {
+        // Connected, print WiFi status
+        printWiFiStatus(status);
 
-    DEBUG_WIFI_MULTI("[WIFIM] Connect timeout\n");
+        // Return WiFi status
+        return status;
+    } else if (status == WL_CONNECT_FAILED) {
+        DEBUG_WIFI_MULTI("[WIFIM] Connect failed\n");
+    } else {
+        DEBUG_WIFI_MULTI("[WIFIM] Connect timeout\n");
+    }
 
+    // Return WiFi connect failed
     return WL_CONNECT_FAILED;
 }
 
@@ -242,24 +232,16 @@ int8_t ESP8266WiFiMulti::startScan()
     // Start wifi scan in async mode
     WiFi.scanNetworks(true);
 
-    // Set WiFi scan timeout
-    using esp8266::polledTimeout::oneShotMs;
-    oneShotMs scanTimeout(WIFI_SCAN_TIMEOUT_MS);
-
     // Wait for WiFi scan change or timeout
-    do {
-        // Refresh watchdog
-        delay(0);
-
-        // Check scan timeout which may occur when scan does not report completion
-        if (scanTimeout) {
-            DEBUG_WIFI_MULTI("[WIFIM] Scan timeout\n");
-            return WIFI_SCAN_FAILED;
-        }
-
-        // Get scan result
-        scanResult = WiFi.scanComplete();
-    } while (scanResult < 0);
+    // The final argument, intvl_ms, to esp_delay influences how frequently
+    // the scheduled recurrent functions (Schedule.h) are probed.
+    esp_delay(WIFI_SCAN_TIMEOUT_MS,
+        [&scanResult]() { scanResult = WiFi.scanComplete(); return scanResult < 0; }, 0);
+    // Check for scan timeout which may occur when scan does not report completion
+    if (scanResult < 0) {
+        DEBUG_WIFI_MULTI("[WIFIM] Scan timeout\n");
+        return WIFI_SCAN_FAILED;
+    }
 
     // Print WiFi scan result
     printWiFiScan();