Fixed result of JsonVariant::set((char*)0) (fixes #1368)

src/ArduinoJson/Json/JsonDeserializer.hpp

@@ -347,8 +347,7 @@ class JsonDeserializer {
     if (!parseQuotedString())
       return false;
     const char *value = _stringStorage.save();
-    variant.setString(make_not_null(value),
-                      typename TStringStorage::storage_policy());
+    variant.setStringPointer(value, typename TStringStorage::storage_policy());
     return true;
   }
 

src/ArduinoJson/MsgPack/MsgPackDeserializer.hpp

@@ -233,8 +233,7 @@ class MsgPackDeserializer {
     const char *s = 0;  // <- mute "maybe-uninitialized" (+4 bytes on AVR)
     if (!readString(s, n))
       return false;
-    variant.setString(make_not_null(s),
-                      typename TStringStorage::storage_policy());
+    variant.setStringPointer(s, typename TStringStorage::storage_policy());
     return true;
   }
 

src/ArduinoJson/Polyfills/gsl/not_null.hpp

@@ -1,34 +0,0 @@
-// ArduinoJson - arduinojson.org
-// Copyright Benoit Blanchon 2014-2020
-// MIT License
-
-#pragma once
-
-#include <ArduinoJson/Namespace.hpp>
-#include <ArduinoJson/Polyfills/assert.hpp>
-
-namespace ARDUINOJSON_NAMESPACE {
-
-template <typename T>
-class not_null {
- public:
-  explicit not_null(T ptr) : _ptr(ptr) {
-    ARDUINOJSON_ASSERT(ptr != NULL);
-  }
-
-  T get() const {
-    ARDUINOJSON_ASSERT(_ptr != NULL);
-    return _ptr;
-  }
-
- private:
-  T _ptr;
-};
-
-template <typename T>
-not_null<T> make_not_null(T ptr) {
-  ARDUINOJSON_ASSERT(ptr != NULL);
-  return not_null<T>(ptr);
-}
-
-}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Variant/VariantData.hpp

@@ -7,7 +7,6 @@
 #include <ArduinoJson/Memory/MemoryPool.hpp>
 #include <ArduinoJson/Misc/SerializedValue.hpp>
 #include <ArduinoJson/Numbers/convertNumber.hpp>
-#include <ArduinoJson/Polyfills/gsl/not_null.hpp>
 #include <ArduinoJson/Strings/RamStringAdapter.hpp>
 #include <ArduinoJson/Variant/VariantContent.hpp>
 
@@ -245,25 +244,14 @@ class VariantData {
     setType(VALUE_IS_NULL);
   }
 
-  void setString(not_null<const char *> s, storage_policies::store_by_copy) {
+  void setStringPointer(const char *s, storage_policies::store_by_copy) {
     setType(VALUE_IS_OWNED_STRING);
-    _content.asString = s.get();
+    _content.asString = s;
   }
 
-  void setString(not_null<const char *> s, storage_policies::store_by_address) {
+  void setStringPointer(const char *s, storage_policies::store_by_address) {
     setType(VALUE_IS_LINKED_STRING);
-    _content.asString = s.get();
-  }
-
-  template <typename TStoragePolicy>
-  bool setString(const char *s, TStoragePolicy storage_policy) {
-    if (s) {
-      setString(make_not_null(s), storage_policy);
-      return true;
-    } else {
-      setType(VALUE_IS_NULL);
-      return false;
-    }
+    _content.asString = s;
   }
 
   template <typename TAdaptedString>
@@ -283,14 +271,27 @@ class VariantData {
   template <typename TAdaptedString>
   inline bool setString(TAdaptedString value, MemoryPool *,
                         storage_policies::store_by_address) {
-    return setString(value.data(), storage_policies::store_by_address());
+    if (value.isNull())
+      setNull();
+    else
+      setStringPointer(value.data(), storage_policies::store_by_address());
+    return true;
   }
 
   template <typename TAdaptedString>
   inline bool setString(TAdaptedString value, MemoryPool *pool,
                         storage_policies::store_by_copy) {
-    return setString(pool->saveString(value),
-                     storage_policies::store_by_copy());
+    if (value.isNull()) {
+      setNull();
+      return true;
+    }
+    const char *copy = pool->saveString(value);
+    if (!copy) {
+      setNull();
+      return false;
+    }
+    setStringPointer(copy, storage_policies::store_by_copy());
+    return true;
   }
 
   CollectionData &toArray() {

src/ArduinoJson/Variant/VariantSlot.hpp

@@ -6,7 +6,6 @@
 
 #include <stdint.h>  // int8_t, int16_t
 
-#include <ArduinoJson/Polyfills/gsl/not_null.hpp>
 #include <ArduinoJson/Polyfills/type_traits.hpp>
 #include <ArduinoJson/Strings/StoragePolicy.hpp>
 #include <ArduinoJson/Variant/VariantContent.hpp>