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