| /* |
| * A simple FIFO implementation. |
| * |
| * Copyright (C) 2004 Stelian Pop <stelian@popies.net> |
| * |
| * 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., 675 Mass Ave, Cambridge, MA 02139, USA. |
| * |
| */ |
| struct fifo { |
| unsigned char *buffer; /* the buffer holding the data */ |
| unsigned int size; /* the size of the allocated buffer */ |
| unsigned int in; /* data is added at offset (in % size) */ |
| unsigned int out; /* data is extracted from off. (out % size) */ |
| }; |
| |
| struct fifo *fifo_alloc(unsigned int); |
| unsigned int fifo_put(struct fifo *, void *, unsigned int); |
| unsigned int fifo_get(struct fifo *, void *, unsigned int); |
| void fifo_free(struct fifo *); |
| |
| static inline unsigned int fifo_len(struct fifo *fifo) |
| { |
| return fifo->in - fifo->out; |
| } |
| |
| static inline unsigned int fifo_room(struct fifo *fifo) |
| { |
| return fifo->size - fifo->in + fifo->out; |
| } |
| |
| #ifndef min |
| #define min(x,y) ({ \ |
| typeof(x) _x = (x); \ |
| typeof(y) _y = (y); \ |
| (void) (&_x == &_y); \ |
| _x < _y ? _x : _y; }) |
| #endif |
| |
| #ifndef max |
| #define max(x,y) ({ \ |
| typeof(x) _x = (x); \ |
| typeof(y) _y = (y); \ |
| (void) (&_x == &_y); \ |
| _x > _y ? _x : _y; }) |
| |
| #endif |