Method Realloc

include/sonic/allocator.h:383–416

Resizes a memory block (concept Allocator)

  //! Resizes a memory block (concept Allocator)
  void* Realloc(void* originalPtr, size_t originalSize, size_t newSize) {
    if (originalPtr == 0) return Malloc(newSize);

    sonic_assert(shared_->refcount > 0);
    if (newSize == 0) return nullptr;

    originalSize = SONIC_ALIGN(originalSize);
    newSize = SONIC_ALIGN(newSize);

    // Do not shrink if new size is smaller than original
    if (originalSize >= newSize) return originalPtr;

    // Simply expand it if it is the last allocation and there is sufficient
    // space
    {
      LOCK_GUARD;
      if (originalPtr ==
          GetChunkBuffer(shared_) + shared_->chunkHead->size - originalSize) {
        size_t increment = static_cast<size_t>(newSize - originalSize);
        if (shared_->chunkHead->size + increment <=
            shared_->chunkHead->capacity) {
          shared_->chunkHead->size += increment;
          return originalPtr;
        }
      }
    }

    // Realloc process: allocate and copy memory, do not free original buffer.
    if (void* newBuffer = Malloc(newSize)) {
      if (originalSize) std::memcpy(newBuffer, originalPtr, originalSize);
      return newBuffer;
    }
    return nullptr;
  }

  //! Frees a memory block (concept Allocator)
  static void Free(void* ptr) noexcept { (void)ptr; }  // Do nothing