BizHawk/psx/octoshock/psx/FastFIFO.h

112 lines
2.2 KiB
C++

/******************************************************************************/
/* Mednafen Sony PS1 Emulation Module */
/******************************************************************************/
/* FastFIFO.h:
** Copyright (C) 2014-2016 Mednafen Team
**
** This program is free software; you can redistribute it and/or
** modify it under the terms of the GNU General Public License
** as published by the Free Software Foundation; either version 2
** of the License, or (at your option) any later version.
**
** This program is distributed in the hope that it will be useful,
** but WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
** GNU General Public License for more details.
**
** You should have received a copy of the GNU General Public License
** along with this program; if not, write to the Free Software Foundation, Inc.,
** 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#ifndef __MDFN_FASTFIFO_H
#define __MDFN_FASTFIFO_H
#include "emuware/EW_state.h"
// size should be a power of 2.
template<typename T, size_t size>
class FastFIFO
{
public:
FastFIFO()
{
memset(data, 0, sizeof(data));
read_pos = 0;
write_pos = 0;
in_count = 0;
}
INLINE ~FastFIFO()
{
}
INLINE void SaveStatePostLoad(void)
{
read_pos %= size;
write_pos %= size;
in_count %= (size + 1);
}
INLINE uint32 CanRead(void)
{
return(in_count);
}
INLINE uint32 CanWrite(void)
{
return(size - in_count);
}
INLINE T Peek(void)
{
return data[read_pos];
}
INLINE T Read(void)
{
T ret = data[read_pos];
read_pos = (read_pos + 1) & (size - 1);
in_count--;
return(ret);
}
INLINE void Write(const T& wr_data)
{
data[write_pos] = wr_data;
write_pos = (write_pos + 1) & (size - 1);
in_count++;
}
INLINE void Flush(void)
{
read_pos = 0;
write_pos = 0;
in_count = 0;
}
T data[size];
uint32 read_pos; // Read position
uint32 write_pos; // Write position
uint32 in_count; // Number of units in the FIFO
template<bool isReader> void SyncState(EW::NewState *ns)
{
//I dont like this class...
NSS(data);
NSS(read_pos);
NSS(write_pos);
NSS(in_count);
SaveStatePostLoad();
}
};
#endif