forked from BSB-WS23/mpstubs
77 lines
2.5 KiB
C
77 lines
2.5 KiB
C
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/*! \file
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* \brief \ref Stringbuffer composes single characters into a buffer
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*/
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#pragma once
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/*! \brief The class Stringbuffer composes single characters into a longer text that can be processed on block.
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*
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* To make Stringbuffer as versatile as possible, the class does make
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* assumptions about neither the underlying hardware, nor the meaning of
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* "processing". When flush() is called (i.e., either on explicit request or
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* once the buffer is full). To be hardware independent, flush() is to be
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* implemented by the derived classes.
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*
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* \par Hints for Implementation
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* Use a buffer of fixed size for caching characters, which should be
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* accessible by derived classes.
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* Keep in mind that the derived implementation of flush() will need to know
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* about numbers of characters in the buffer.
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*
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* \par Notes
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* Reason for the existence of this class is that generating longer texts is
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* often implemented by assembly of small fragments (such as single characters
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* or numbers).
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* However, writing such small fragments directly to (for example) screen is
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* quite inefficient (e.g., due to the use of IO ports, syscalls, or locks) and
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* can be improved drastically by delaying the output step until the assembly
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* is finished (or the buffer runs full).
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*/
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class Stringbuffer {
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// Prevent copies and assignments
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Stringbuffer(const Stringbuffer&) = delete;
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Stringbuffer& operator=(const Stringbuffer&) = delete;
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// All variables and methods are protected in this class,
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// as the derived classes need direct access to be buffer,
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// the constructor, the destructor, and the method put.
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// flush() is to be implemented either way and may be redefined
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// as public.
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protected:
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/// buffer containing characters that will be printed upon flush()
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char buffer[80];
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/// current position in the buffer
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long unsigned pos;
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/*! \brief Constructor; Marks the buffer as empty
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*
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* \todo Complete Constructor
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*/
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Stringbuffer() { }
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/*! \brief Inserts a character into the buffer.
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*
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* Once the buffer is full, a call to flush() will be issued and
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* thereby clearing the buffer.
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*
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* \todo Implement Method
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*
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* \param c Char to be added
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*/
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void put(char c);
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/*! \brief Flush the buffer contents
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*
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* This method is to be defined in derived classes, as only those know
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* how to print characters.
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* flush() is required to reset the position pos.
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*/
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virtual void flush() = 0;
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public:
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/*! \brief Destructor (nothing to do here)
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*/
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virtual ~Stringbuffer() { }
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};
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