From 54f51ad2cd99b7efee728c627e0baab8cbe7c545 Mon Sep 17 00:00:00 2001
From: Maxim Prokhorov <prokhorov.max@outlook.com>
Date: Thu, 24 Dec 2020 16:19:24 +0300
Subject: [PATCH] sns: more lenient eneTotal parser

---
 code/espurna/sensor.cpp | 32 ++++++++++++++++++++++++++------
 1 file changed, 26 insertions(+), 6 deletions(-)

diff --git a/code/espurna/sensor.cpp b/code/espurna/sensor.cpp
index b1ec9642..e4525a74 100644
--- a/code/espurna/sensor.cpp
+++ b/code/espurna/sensor.cpp
@@ -428,14 +428,34 @@ void _sensorRtcmemSaveEnergy(unsigned char index, const sensor::Energy& source)
 
 sensor::Energy _sensorParseEnergy(const String& value) {
     sensor::Energy result;
+    if (!value.length()) {
+        return result;
+    }
+
+    const char* p { value.c_str() };
+
+    char* endp { nullptr };
+    auto kwh = strtoul(p, &endp, 10);
+    if (!endp || (endp == p)) {
+        return result;
+    }
+    result.kwh = kwh;
 
-    const bool separator = value.indexOf('+') > 0;
-    if (value.length() && (separator > 0)) {
-        const String before = value.substring(0, separator);
-        const String after = value.substring(separator + 1);
-        result.kwh = strtoul(before.c_str(), nullptr, 10);
-        result.ws = strtoul(after.c_str(), nullptr, 10);
+    const char* plus { strchr(p, '+') };
+    if (!plus) {
+        return;
+    }
+
+    p = plus + 1;
+    if (*p == '\0') {
+        return result;
+    }
+
+    auto ws = strtoul(p, &endp, 10);
+    if (!endp || (endp == p)) {
+        return result;
     }
+    result.ws = ws;
 
     return result;
 }