array.hh

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#ifndef __SYSTEMC_EXT_TLM_CORE_2_GENERIC_PAYLOADS_ARRAY_HH__
#define __SYSTEMC_EXT_TLM_CORE_2_GENERIC_PAYLOADS_ARRAY_HH__

#include <vector>

namespace tlm
{

// This implements a lean and fast array class that supports array expansion on
// request. The class is primarily used in the tlm_generic_payload class for
// storing the pointers to the extensions.
//
// Individual array elements can be accessed through the [] operators, and the
// array length is returned by the size() method.
//
// The size can be dynamically expanded using the expand(uint) method. There
// is no shrinking mechanism implemented, because the extension mechanism
// does not require this feature. Bear in mind that calling the expand method
// may invalidate all direct pointers into the array.


// The tlm_array shall always be used with T=tlm_extension_base*.
template <typename T>
class tlm_array : private std::vector<T>
{
  private:
    typedef std::vector<T> base_type;
    typedef typename base_type::size_type size_type;

  public:
    tlm_array(size_type size=0) : base_type(size), m_entries() {}

    // Operators for dereferencing:
    using base_type::operator [];

    // Array size:
    using base_type::size;

    // Expand the array if needed:
    void
    expand(size_type new_size)
    {
        if (new_size > size())
            base_type::resize(new_size);
    }

    static const char *const kind_string;
    const char *kind() const { return kind_string; }

    // This function shall get a pointer to an array slot
    // it stores this slot in a cache of active slots
    void insert_in_cache(T *p) { m_entries.push_back(p - &(*this)[0]); }

    // This functions clears all active slots of the array.
    void
    free_entire_cache()
    {
        while (m_entries.size()) {
            // We make sure no one cleared the slot manually.
            if ((*this)[m_entries.back()]) {
                // ...and then we call free on the content of the slot
                (*this)[m_entries.back()]->free();
            }
            // Afterwards we set the slot to NULL
            (*this)[m_entries.back()] = nullptr;
            m_entries.pop_back();
        }
    }

  protected:
    std::vector<size_type> m_entries;
};

template <typename T>
const char *const tlm_array<T>::kind_string = "tlm_array";

} // namespace tlm

#endif /* __SYSTEMC_EXT_TLM_CORE_2_GENERIC_PAYLOADS_ARRAY_HH__ */