: block_size_(block_size), max_size_(max_size), total_allocated_(0) {

primary_ = allocate_block(block_size_);

current_ = primary_;

total_allocated_ = block_size_;

void* mem = allocate(len);

if (!mem) return StringRef{nullptr, 0};

std::memcpy(mem, src, len);

return StringRef{static_cast<const char*>(mem), len};

Block* b = primary_->next;

while (b) {

Block* next = b->next;

std::free(b);

b = next;

}

primary_->next = nullptr;

primary_->used = 0;

current_ = primary_;

total_allocated_ = block_size_;

size_t used = 0;

const Block* b = primary_;

while (b) {

used += b->used;

b = b->next;

}

return used;