From 3fe7c2e8cdcc34af0f5d3c55f8b4cb79ef5318cf Mon Sep 17 00:00:00 2001
From: lbernstone <lbernstone@gmail.com>
Date: Wed, 24 Feb 2021 10:04:36 -0700
Subject: [PATCH] Add div by zero check back into WMath::map (#4853)

* Add div by zero check back into WMath::map
* include esp32-hal-log.h

Co-authored-by: Me No Dev <me-no-dev@users.noreply.github.com>
---
 cores/esp32/WMath.cpp | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/cores/esp32/WMath.cpp b/cores/esp32/WMath.cpp
index d351b194..d7017165 100644
--- a/cores/esp32/WMath.cpp
+++ b/cores/esp32/WMath.cpp
@@ -27,6 +27,7 @@ extern "C" {
 #include <stdlib.h>
 #include "esp_system.h"
 }
+#include "esp32-hal-log.h"
 
 void randomSeed(unsigned long seed)
 {
@@ -69,7 +70,10 @@ long map(long x, long in_min, long in_max, long out_min, long out_max) {
     const long dividend = out_max - out_min;
     const long divisor = in_max - in_min;
     const long delta = x - in_min;
-
+    if(divisor == 0){
+        log_e("Invalid map input range, min == max");
+        return -1; //AVR returns -1, SAM returns 0
+    }
     return (delta * dividend + (divisor / 2)) / divisor + out_min;
 }