Class Iterator

src/test/common/ObjectContents.h:23–74

  bool _exists;
public:
  class Iterator {
    ObjectContents *parent;
    std::map<uint64_t, unsigned int>::iterator iter;
    unsigned int current_state;
    int current_val;
    uint64_t pos;
  private:
    unsigned int get_state(uint64_t pos);
  public:
    explicit Iterator(ObjectContents *parent) :
      parent(parent), iter(parent->seeds.end()),
      current_state(0), current_val(0), pos(-1) {
      seek_to_first();
    }
    char operator*() {
      return parent->written.contains(pos) ?
	static_cast<char>(current_val % 256) : '\0';
    }
    uint64_t get_pos() {
      return pos;
    }
    void seek_to(uint64_t _pos) {
      if (pos > _pos ||
	  (iter != parent->seeds.end() && _pos >= iter->first)) {
	iter = parent->seeds.upper_bound(_pos);
	--iter;
	current_state = iter->second;
	current_val = rand_r(&current_state);
	pos = iter->first;
	++iter;
      }
      while (pos < _pos) ++(*this);
    }

    void seek_to_first() {
      seek_to(0);
    }
    Iterator &operator++() {
      ++pos;
      if (iter != parent->seeds.end() && pos >= iter->first) {
	ceph_assert(pos == iter->first);
	current_state = iter->second;
	++iter;
      }
      current_val = rand_r(&current_state);
      return *this;
    }
    bool valid() {
      return pos < parent->size();
    }
    friend class ObjectContents;
  };

  ObjectContents() : _size(0), _exists(false) {
    seeds[0] = 0;