VariantSlot stores a StringNode* for owned keys

bblanchon · Jul 7, 2023 · 324b1e5 · 324b1e5
1 parent 04d7ec3
commit 324b1e5
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Showing 5 changed files with 26 additions and 18 deletions.
diff --git a/src/ArduinoJson/Memory/ResourceManager.hpp b/src/ArduinoJson/Memory/ResourceManager.hpp
@@ -114,7 +114,7 @@ class ResourceManager {
     StringNode::destroy(node, allocator_);
   }
 
-  void dereferenceString(const char* s) {
+  void dereferenceString(StringNode* s) {
     stringPool_.dereference(s, allocator_);
   }
 

diff --git a/src/ArduinoJson/Memory/StringPool.hpp b/src/ArduinoJson/Memory/StringPool.hpp
@@ -82,21 +82,23 @@ class StringPool {
     return nullptr;
   }
 
-  void dereference(const char* s, Allocator* allocator) {
+  void dereference(StringNode* s, Allocator* allocator) {
+    ARDUINOJSON_ASSERT(s != nullptr);
+    ARDUINOJSON_ASSERT(s->references > 0);
+    if (--s->references > 0)
+      return;
     StringNode* prev = nullptr;
     for (auto node = strings_; node; node = node->next) {
-      if (node->data == s) {
-        if (--node->references == 0) {
-          if (prev)
-            prev->next = node->next;
-          else
-            strings_ = node->next;
-          StringNode::destroy(node, allocator);
-        }
-        return;
+      if (node == s) {
+        if (prev)
+          prev->next = node->next;
+        else
+          strings_ = node->next;
+        break;
       }
       prev = node;
     }
+    StringNode::destroy(s, allocator);
   }
 
  private:

diff --git a/src/ArduinoJson/Variant/SlotFunctions.hpp b/src/ArduinoJson/Variant/SlotFunctions.hpp
@@ -20,7 +20,7 @@ inline size_t slotSize(const VariantSlot* var) {
 
 inline void VariantSlot::release(ResourceManager* resources) {
   if (flags_ & OWNED_KEY_BIT)
-    resources->dereferenceString(key_);
+    resources->dereferenceString(ownedKey_);
   data()->setNull(resources);
 }
 

diff --git a/src/ArduinoJson/Variant/VariantData.hpp b/src/ArduinoJson/Variant/VariantData.hpp
@@ -545,7 +545,7 @@ class VariantData {
  private:
   void release(ResourceManager* resources) {
     if (flags_ & OWNED_VALUE_BIT)
-      resources->dereferenceString(content_.asOwnedString->data);
+      resources->dereferenceString(content_.asOwnedString);
 
     auto collection = asCollection();
     if (collection)

diff --git a/src/ArduinoJson/Variant/VariantSlot.hpp b/src/ArduinoJson/Variant/VariantSlot.hpp
@@ -23,7 +23,10 @@ class VariantSlot {
   VariantContent content_;
   uint8_t flags_;
   VariantSlotDiff next_;
-  const char* key_;
+  union {
+    StringNode* ownedKey_;
+    const char* linkedKey_;
+  };
 
  public:
   // Placement new
@@ -33,7 +36,7 @@ class VariantSlot {
 
   static void operator delete(void*, void*) noexcept {}
 
-  VariantSlot() : flags_(0), next_(0), key_(0) {}
+  VariantSlot() : flags_(0), next_(0), linkedKey_(0) {}
 
   void release(ResourceManager* resources);
 
@@ -73,17 +76,20 @@ class VariantSlot {
   void setKey(const char* k) {
     ARDUINOJSON_ASSERT(k);
     flags_ &= VALUE_MASK;
-    key_ = k;
+    linkedKey_ = k;
   }
 
   void setKey(StringNode* k) {
     ARDUINOJSON_ASSERT(k);
     flags_ |= OWNED_KEY_BIT;
-    key_ = k->data;
+    ownedKey_ = k;
   }
 
   const char* key() const {
-    return key_;
+    if (flags_ & OWNED_KEY_BIT)
+      return ownedKey_->data;
+    else
+      return linkedKey_;
   }
 
   bool ownsKey() const {