melonDS/FIFO.cpp

73 lines
1.4 KiB
C++

/*
Copyright 2016-2017 StapleButter
This file is part of melonDS.
melonDS 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 3 of the License, or (at your option)
any later version.
melonDS 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 melonDS. If not, see http://www.gnu.org/licenses/.
*/
#include "FIFO.h"
FIFO::FIFO(u32 num)
{
NumEntries = num;
Entries = new u32[num];
Clear();
}
FIFO::~FIFO()
{
delete[] Entries;
}
void FIFO::Clear()
{
NumOccupied = 0;
ReadPos = 0;
WritePos = 0;
Entries[ReadPos] = 0;
}
void FIFO::Write(u32 val)
{
if (IsFull()) return;
Entries[WritePos] = val;
WritePos++;
if (WritePos >= NumEntries)
WritePos = 0;
NumOccupied++;
}
u32 FIFO::Read()
{
u32 ret = Entries[ReadPos];
if (IsEmpty())
return ret;
ReadPos++;
if (ReadPos >= NumEntries)
ReadPos = 0;
NumOccupied--;
return ret;
}
u32 FIFO::Peek()
{
return Entries[ReadPos];
}