Manage resources in CollectionData

src/ArduinoJson/Array/JsonArrayConst.hpp

@@ -5,6 +5,7 @@
 #pragma once
 
 #include <ArduinoJson/Array/JsonArrayIterator.hpp>
+#include <ArduinoJson/Collection/CollectionFunctions.hpp>
 #include <ArduinoJson/Variant/VariantAttorney.hpp>
 #include <ArduinoJson/Variant/VariantData.hpp>
 
@@ -51,7 +52,7 @@ class JsonArrayConst : public detail::VariantOperators<JsonArrayConst> {
   // Returns the element at the specified index.
   // https://arduinojson.org/v6/api/jsonarrayconst/subscript/
   FORCE_INLINE JsonVariantConst operator[](size_t index) const {
-    return JsonVariantConst(data_ ? slotData(data_->get(index)) : 0);
+    return JsonVariantConst(collectionGetElement(data_, index));
   }
 
   operator JsonVariantConst() const {

src/ArduinoJson/Collection/CollectionData.hpp

@@ -15,16 +15,46 @@ class VariantData;
 class VariantSlot;
 
 class CollectionData {
-  VariantSlot* head_;
-  VariantSlot* tail_;
+  VariantSlot* head_ = 0;
+  VariantSlot* tail_ = 0;
 
  public:
-  void clear();
+  // Placement new
+  static void* operator new(size_t, void* p) noexcept {
+    return p;
+  }
+
+  static void operator delete(void*, void*) noexcept {}
+
   size_t memoryUsage() const;
   size_t size() const;
 
-  void add(VariantSlot*);
-  void remove(VariantSlot* slot);
+  VariantData* addElement(ResourceManager* resources);
+
+  VariantData* addMember(StringNode* key, ResourceManager* resources);
+
+  template <typename TAdaptedString>
+  VariantData* addMember(TAdaptedString key, ResourceManager* resources);
+
+  void clear(ResourceManager* resources);
+  bool copyFrom(const CollectionData& src, ResourceManager* resources);
+
+  VariantData* getOrAddElement(size_t index, ResourceManager* resources);
+
+  VariantData* getElement(size_t index) const;
+
+  template <typename TAdaptedString>
+  VariantData* getOrAddMember(TAdaptedString key, ResourceManager* resources);
+
+  template <typename TAdaptedString>
+  VariantData* getMember(TAdaptedString key) const;
+
+  void removeSlot(VariantSlot* slot, ResourceManager* resources);
+
+  void removeElement(size_t index, ResourceManager* resources);
+
+  template <typename TAdaptedString>
+  void removeMember(TAdaptedString key, ResourceManager* resources);
 
   VariantSlot* head() const {
     return head_;
@@ -32,13 +62,15 @@ class CollectionData {
 
   void movePointers(ptrdiff_t variantDistance);
 
-  VariantSlot* get(size_t index) const;
+ private:
+  void addSlot(VariantSlot*);
+
+  VariantSlot* getPreviousSlot(VariantSlot*) const;
+
+  VariantSlot* getSlot(size_t index) const;
 
   template <typename TAdaptedString>
-  VariantSlot* get(TAdaptedString key) const;
-
- private:
-  VariantSlot* getPrevious(VariantSlot*) const;
+  VariantSlot* getSlot(TAdaptedString key) const;
 };
 
 inline const VariantData* collectionToVariant(

src/ArduinoJson/Collection/CollectionFunctions.hpp

@@ -12,39 +12,20 @@ inline VariantData* collectionAddElement(CollectionData* array,
                                          ResourceManager* resources) {
   if (!array)
     return nullptr;
-  auto slot = resources->allocVariant();
-  if (!slot)
-    return nullptr;
-  array->add(slot);
-  return slot->data();
+  return array->addElement(resources);
 }
 
 template <typename TAdaptedString>
 inline VariantData* collectionAddMember(CollectionData* obj, TAdaptedString key,
                                         ResourceManager* resources) {
-  ARDUINOJSON_ASSERT(!key.isNull());
   ARDUINOJSON_ASSERT(obj != nullptr);
-  auto slot = resources->allocVariant();
-  if (!slot)
-    return nullptr;
-  if (key.isLinked())
-    slot->setKey(key.data());
-  else {
-    auto storedKey = resources->saveString(key);
-    if (!storedKey)
-      return nullptr;
-    slot->setKey(storedKey);
-  }
-  obj->add(slot);
-  return slot->data();
+  return obj->addMember(key, resources);
 }
 
 inline void collectionClear(CollectionData* c, ResourceManager* resources) {
   if (!c)
     return;
-  for (auto slot = c->head(); slot; slot = slot->next())
-    slotRelease(slot, resources);
-  c->clear();
+  c->clear(resources);
 }
 
 inline bool collectionCopy(CollectionData* dst, const CollectionData* src,
@@ -52,21 +33,14 @@ inline bool collectionCopy(CollectionData* dst, const CollectionData* src,
   if (!dst || !src)
     return false;
 
-  collectionClear(dst, resources);
+  return dst->copyFrom(*src, resources);
+}
 
-  for (VariantSlot* s = src->head(); s; s = s->next()) {
-    VariantData* var;
-    if (s->key() != 0) {
-      JsonString key(s->key(),
-                     s->ownsKey() ? JsonString::Copied : JsonString::Linked);
-      var = collectionAddMember(dst, adaptString(key), resources);
-    } else {
-      var = collectionAddElement(dst, resources);
-    }
-    if (!variantCopyFrom(var, s->data(), resources))
-      return false;
-  }
-  return true;
+inline VariantData* collectionGetElement(const CollectionData* obj,
+                                         size_t index) {
+  if (!obj)
+    return nullptr;
+  return obj->getElement(index);
 }
 
 template <typename TAdaptedString>
@@ -74,22 +48,21 @@ inline VariantData* collectionGetMember(const CollectionData* obj,
                                         TAdaptedString key) {
   if (!obj)
     return nullptr;
-  return slotData(obj->get(key));
+  return obj->getMember(key);
 }
 
 inline void collectionRemove(CollectionData* data, VariantSlot* slot,
                              ResourceManager* resources) {
-  if (!data || !slot)
+  if (!data)
     return;
-  data->remove(slot);
-  slotRelease(slot, resources);
+  data->removeSlot(slot, resources);
 }
 
 inline void collectionRemoveElement(CollectionData* array, size_t index,
                                     ResourceManager* resources) {
   if (!array)
     return;
-  collectionRemove(array, array->get(index), resources);
+  array->removeElement(index, resources);
 }
 
 template <typename TAdaptedString>
@@ -97,7 +70,7 @@ inline void collectionRemoveMember(CollectionData* obj, TAdaptedString key,
                                    ResourceManager* resources) {
   if (!obj)
     return;
-  collectionRemove(obj, obj->get(key), resources);
+  obj->removeMember(key, resources);
 }
 
 ARDUINOJSON_END_PRIVATE_NAMESPACE

src/ArduinoJson/Collection/CollectionImpl.hpp

@@ -11,7 +11,7 @@
 
 ARDUINOJSON_BEGIN_PRIVATE_NAMESPACE
 
-inline void CollectionData::add(VariantSlot* slot) {
+inline void CollectionData::addSlot(VariantSlot* slot) {
   ARDUINOJSON_ASSERT(slot != nullptr);
 
   if (tail_) {
@@ -23,13 +23,110 @@ inline void CollectionData::add(VariantSlot* slot) {
   }
 }
 
-inline void CollectionData::clear() {
+inline VariantData* CollectionData::addElement(ResourceManager* resources) {
+  auto slot = resources->allocVariant();
+  if (!slot)
+    return nullptr;
+  addSlot(slot);
+  return slot->data();
+}
+
+inline VariantData* CollectionData::addMember(StringNode* key,
+                                              ResourceManager* resources) {
+  ARDUINOJSON_ASSERT(key != nullptr);
+  auto slot = resources->allocVariant();
+  if (!slot)
+    return nullptr;
+
+  slot->setKey(key);
+  addSlot(slot);
+  return slot->data();
+}
+
+template <typename TAdaptedString>
+inline VariantData* CollectionData::addMember(TAdaptedString key,
+                                              ResourceManager* resources) {
+  ARDUINOJSON_ASSERT(!key.isNull());
+  auto slot = resources->allocVariant();
+  if (!slot)
+    return nullptr;
+  if (key.isLinked())
+    slot->setKey(key.data());
+  else {
+    auto storedKey = resources->saveString(key);
+    if (!storedKey)
+      return nullptr;
+    slot->setKey(storedKey);
+  }
+  addSlot(slot);
+  return slot->data();
+}
+
+template <typename TAdaptedString>
+inline VariantData* CollectionData::getMember(TAdaptedString key) const {
+  return slotData(getSlot(key));
+}
+
+inline VariantData* CollectionData::getOrAddElement(
+    size_t index, ResourceManager* resources) {
+  VariantSlot* slot = head_;
+  while (slot && index > 0) {
+    slot = slot->next();
+    index--;
+  }
+  if (!slot)
+    index++;
+  while (index > 0) {
+    slot = resources->allocVariant();
+    if (!slot)
+      return nullptr;
+    addSlot(slot);
+    index--;
+  }
+  return slot->data();
+}
+
+template <typename TAdaptedString>
+VariantData* CollectionData::getOrAddMember(TAdaptedString key,
+                                            ResourceManager* resources) {
+  auto slot = getSlot(key);
+  if (slot)
+    return slot->data();
+  return addMember(key, resources);
+}
+
+inline VariantData* CollectionData::getElement(size_t index) const {
+  return slotData(getSlot(index));
+}
+
+inline void CollectionData::clear(ResourceManager* resources) {
+  for (auto slot = head_; slot; slot = slot->next())
+    slotRelease(slot, resources);
   head_ = 0;
   tail_ = 0;
 }
 
+inline bool CollectionData::copyFrom(const CollectionData& src,
+                                     ResourceManager* resources) {
+  clear(resources);
+
+  for (VariantSlot* s = src.head(); s; s = s->next()) {
+    VariantData* var;
+    if (s->key() != 0) {
+      JsonString key(s->key(),
+                     s->ownsKey() ? JsonString::Copied : JsonString::Linked);
+      var = addMember(adaptString(key), resources);
+    } else {
+      var = addElement(resources);
+    }
+    if (!variantCopyFrom(var, s->data(), resources))
+      return false;
+  }
+  return true;
+}
+
 template <typename TAdaptedString>
-inline VariantSlot* CollectionData::get(TAdaptedString key) const {
+inline VariantSlot* CollectionData::getSlot(TAdaptedString key) const {
   if (key.isNull())
     return 0;
   VariantSlot* slot = head_;
@@ -41,13 +138,13 @@ inline VariantSlot* CollectionData::get(TAdaptedString key) const {
   return slot;
 }
 
-inline VariantSlot* CollectionData::get(size_t index) const {
+inline VariantSlot* CollectionData::getSlot(size_t index) const {
   if (!head_)
     return 0;
   return head_->next(index);
 }
 
-inline VariantSlot* CollectionData::getPrevious(VariantSlot* target) const {
+inline VariantSlot* CollectionData::getPreviousSlot(VariantSlot* target) const {
   VariantSlot* current = head_;
   while (current) {
     VariantSlot* next = current->next();
@@ -58,9 +155,11 @@ inline VariantSlot* CollectionData::getPrevious(VariantSlot* target) const {
   return 0;
 }
 
-inline void CollectionData::remove(VariantSlot* slot) {
-  ARDUINOJSON_ASSERT(slot != nullptr);
-  VariantSlot* prev = getPrevious(slot);
+inline void CollectionData::removeSlot(VariantSlot* slot,
+                                       ResourceManager* resources) {
+  if (!slot)
+    return;
+  VariantSlot* prev = getPreviousSlot(slot);
   VariantSlot* next = slot->next();
   if (prev)
     prev->setNext(next);
@@ -68,6 +167,18 @@ inline void CollectionData::remove(VariantSlot* slot) {
     head_ = next;
   if (!next)
     tail_ = prev;
+  slotRelease(slot, resources);
+}
+
+inline void CollectionData::removeElement(size_t index,
+                                          ResourceManager* resources) {
+  removeSlot(getSlot(index), resources);
+}
+
+template <typename TAdaptedString>
+inline void CollectionData::removeMember(TAdaptedString key,
+                                         ResourceManager* resources) {
+  removeSlot(getSlot(key), resources);
 }
 
 inline size_t CollectionData::memoryUsage() const {
@@ -128,10 +239,10 @@ inline bool arrayEquals(const CollectionData* lhs, const CollectionData* rhs) {
 inline bool objectEquals(const CollectionData& lhs, const CollectionData& rhs) {
   size_t count = 0;
   for (auto a = lhs.head(); a; a = a->next()) {
-    auto b = rhs.get(adaptString(a->key()));
+    auto b = rhs.getMember(adaptString(a->key()));
     if (!b)
       return false;
-    if (compare(a->data(), b->data()) != COMPARE_RESULT_EQUAL)
+    if (compare(a->data(), b) != COMPARE_RESULT_EQUAL)
       return false;
     count++;
   }

src/ArduinoJson/Json/JsonDeserializer.hpp

@@ -273,25 +273,21 @@ class JsonDeserializer {
       TFilter memberFilter = filter[key.c_str()];
 
       if (memberFilter.allow()) {
-        VariantSlot* slot = object.get(adaptString(key.c_str()));
-        if (!slot) {
+        auto member = object.getMember(adaptString(key.c_str()));
+        if (!member) {
           // Save key in memory pool.
           auto savedKey = stringBuilder_.save();
 
           // Allocate slot in object
-          slot = resources_->allocVariant();
-          if (!slot)
+          member = object.addMember(savedKey, resources_);
+          if (!member)
             return DeserializationError::NoMemory;
-
-          slot->setKey(savedKey);
-          object.add(slot);
         } else {
-          slot->data()->setNull(resources_);
+          member->setNull(resources_);
         }
 
         // Parse value
-        err =
-            parseVariant(*slot->data(), memberFilter, nestingLimit.decrement());
+        err = parseVariant(*member, memberFilter, nestingLimit.decrement());
         if (err)
           return err;
       } else {

src/ArduinoJson/MsgPack/MsgPackDeserializer.hpp

@@ -495,14 +495,9 @@ class MsgPackDeserializer {
         // Save key in memory pool.
         auto savedKey = stringBuilder_.save();
 
-        VariantSlot* slot = resources_->allocVariant();
-        if (!slot)
+        member = object->addMember(savedKey, resources_);
+        if (!member)
           return DeserializationError::NoMemory;
-
-        slot->setKey(savedKey);
-        object->add(slot);
-
-        member = slot->data();
       } else {
         member = 0;
       }

src/ArduinoJson/Object/JsonObject.hpp

@@ -201,11 +201,6 @@ class JsonObject : public detail::VariantOperators<JsonObject> {
     return detail::collectionToVariant(data_);
   }
 
-  template <typename TAdaptedString>
-  void removeMember(TAdaptedString key) const {
-    collectionRemove(data_, data_->get(key), resources_);
-  }
-
   detail::CollectionData* data_;
   detail::ResourceManager* resources_;
 };

src/ArduinoJson/Variant/VariantContent.hpp

@@ -38,6 +38,8 @@ enum {
 };
 
 union VariantContent {
+  VariantContent() {}
+
   JsonFloat asFloat;
   bool asBoolean;
   JsonUInt asUnsignedInteger;

src/ArduinoJson/Variant/VariantData.hpp

@@ -211,7 +211,7 @@ class VariantData {
     auto array = asArray();
     if (!array)
       return nullptr;
-    return slotData(array->get(index));
+    return array->getElement(index);
   }
 
   template <typename TAdaptedString>
@@ -219,28 +219,14 @@ class VariantData {
     auto object = asObject();
     if (!object)
       return nullptr;
-    return slotData(object->get(key));
+    return object->getMember(key);
   }
 
   VariantData* getOrAddElement(size_t index, ResourceManager* resources) {
     auto array = isNull() ? &toArray() : asArray();
     if (!array)
       return nullptr;
-    VariantSlot* slot = array->head();
-    while (slot && index > 0) {
-      slot = slot->next();
-      index--;
-    }
-    if (!slot)
-      index++;
-    while (index > 0) {
-      slot = resources->allocVariant();
-      if (!slot)
-        return nullptr;
-      array->add(slot);
-      index--;
-    }
-    return slot->data();
+    return array->getOrAddElement(index, resources);
   }
 
   template <typename TAdaptedString>
@@ -250,10 +236,7 @@ class VariantData {
     auto obj = isNull() ? &toObject() : asObject();
     if (!obj)
       return nullptr;
-    auto slot = obj->get(key);
-    if (slot)
-      return slot->data();
-    return collectionAddMember(obj, key, resources);
+    return obj->getOrAddMember(key, resources);
   }
 
   bool isArray() const {
@@ -446,7 +429,7 @@ class VariantData {
 
   CollectionData& toArray() {
     setType(VALUE_IS_ARRAY);
-    content_.asCollection.clear();
+    new (&content_.asCollection) CollectionData();
     return content_.asCollection;
   }
 
@@ -457,7 +440,7 @@ class VariantData {
 
   CollectionData& toObject() {
     setType(VALUE_IS_OBJECT);
-    content_.asCollection.clear();
+    new (&content_.asCollection) CollectionData();
     return content_.asCollection;
   }