Array.h

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/*****************************************************************************
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 *  Copyright 2018 Rice University                                           *
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 *  Licensed under the Apache License, Version 2.0 (the "License");          *
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 *  distributed under the License is distributed on an "AS IS" BASIS,        *
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#include "Object.h"
#include "PDBTemplateBase.h"
#include "Handle.h"

#ifndef ARRAY_H
#define ARRAY_H

#include <cstddef>
#include <iostream>
#include <iterator>
#include <cstring>

// PRELOAD %Array <Nothing>%

namespace pdb {


// The Array type is the one type that we allow to be variable length.  This is accomplished
// the the data[] array at the end of the class.  When an Array object is alllocated, it is
// always allocated with some extra space at the end of the class to allow this array to
// be used.
//
// Since the array class can be variable length, it is used as the key building block for
// both the Vector and String classes.

template <class TypeContained>
class Array : public Object {

public:
    // constructor/sdestructor
    Array();
    Array(uint32_t numSlots);
    Array(const Array& copyFromMe);
    ~Array();

    // this constructor pre-allocates the given number of slots, and initializes the specified
    // number,
    // so that the number of used slots is equal to the secod parameter
    Array(uint32_t numSlots, uint32_t numUsedSlots);

    // normally these would be defined by the ENABLE_DEEP_COPY macro, but because
    // Array is the one variable-sized type that we allow, we need to manually override
    // these methods
    void setUpAndCopyFrom(void* target, void* source) const;
    void deleteObject(void* deleteMe);
    size_t getSize(void* forMe);

private:
    // and this gives us our info about TypeContained
    PDBTemplateBase typeInfo;

    // the number of slots actually used
    uint32_t usedSlots;

    // the number of slots
    uint32_t numSlots;

    // the array of data
    Nothing data[0];

public:
    // create a new Array object of size howMany, and copy our contents into it
    Handle<Array<TypeContained>> resize(uint32_t howMany);

    // get a pointer to the data
    TypeContained* c_ptr();

    // access a particular object in the array, by index
    TypeContained& getObj(uint32_t which);

    // assign a particular item in the array
    void assign(uint32_t which, const TypeContained& val);

    // add to the end
    void push_back(const TypeContained& val);

    // add an empty item at the end
    void push_back();

    // remove from the end and shrink the number of used slots
    void pop_back();

    // return a new array that is twice the size, containing the same contents
    Handle<Array<TypeContained>> doubleSize();

    // check if the array is full
    bool isFull();

    // return/set the number of used slots
    uint32_t numUsedSlots();
    void setUsed(uint32_t toMe);

    // beause the communicator needs to see inside to do efficient sends
    friend class PDBCommunicator;
};
}

#include "Array.cc"

#endif