62 lines
1.9 KiB
C
62 lines
1.9 KiB
C
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/*
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* Not Thread Safe !
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*/
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#pragma once
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#include <stddef.h>
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class Filler
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{
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public:
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virtual size_t Read(void *dest, size_t len)=0;
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};
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class Drainer
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{
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public:
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virtual size_t Write(const void *dest, size_t len)=0;
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};
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class RingBuffer
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{
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public:
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RingBuffer();
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~RingBuffer();
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void Reset();
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bool reserve( size_t bytes ); // destructive.
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int expand( size_t bytes ); // like reserve, but only expands upward. non-destructive. returns an NError
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bool empty() const;
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size_t avail() const; // how much available for writing
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size_t size() const; // how much available for reading
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void clear();
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size_t read( void *dest, size_t len ); // returns amount actually read
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size_t advance( size_t len ); // same as read() but doesn't write the data any where.
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size_t peek( void *dest, size_t len ) const; // same as read() but doesn't advance the read pointer
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size_t write( const void *src, size_t len );
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size_t fill( Filler *filler, size_t max_bytes );
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size_t drain( Drainer *drainer, size_t max_bytes );
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size_t at( size_t offset, void *dest, size_t len ) const; // peeks() from offset. returns bytes read
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size_t write_position() const; // returns an integer representing a write position
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size_t read_position() const; // returns an integer representing the read position
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void get_read_buffer( size_t bytes, const void **buffer, size_t *bytes_available ) const; /* returns a pointer that you can read data from, call advance() when you are done */
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/* DO NOT USING THIS UNLESS YOU KNOW WHAT YOU'RE DOING
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you should only use it when the ring buffer is empty
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1) call clear() beforehand - very important!
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2) call LockBuffer(), it'll give you a buffer
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3) call UnlockBufer() with how much you've written
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4) you catch the man
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*/
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void *LockBuffer();
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void UnlockBuffer( size_t written );
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private:
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volatile size_t ringBufferUsed;
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size_t ringBufferSize;
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char *ringBuffer;
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char *ringWritePosition;
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char *ringReadPosition;
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};
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