1 /***************************************************************************
3 * Open \______ \ ____ ____ | | _\_ |__ _______ ___
4 * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
5 * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
6 * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
8 * $Id: skin_buffer.c 25962 2010-05-12 09:31:40Z jdgordon $
10 * Copyright (C) 2002 by Linus Nielsen Feltzing
11 * Copyright (C) 2009 Jonathan Gordon
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License
15 * as published by the Free Software Foundation; either version 2
16 * of the License, or (at your option) any later version.
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
21 ****************************************************************************/
27 #include "skin_buffer.h"
30 static size_t buf_size
;
31 static unsigned char *buffer_start
= NULL
;
32 static unsigned char *buffer_front
= NULL
;
35 void skin_buffer_init(char* buffer
, size_t size
)
38 buffer_start
= buffer_front
= buffer
;
43 /* Allocate size bytes from the buffer */
44 void* skin_buffer_alloc(size_t size
)
48 if (size
> skin_buffer_freespace())
50 retval
= buffer_front
;
53 buffer_front
= (void *)(((unsigned long)buffer_front
+ 3) & ~3);
55 retval
= malloc(size
);
62 /* get the number of bytes currently being used */
63 size_t skin_buffer_usage(void)
65 return buffer_front
- buffer_start
;
67 size_t skin_buffer_freespace(void)
69 return buf_size
- skin_buffer_usage();
72 static unsigned char *saved_buffer_pos
= NULL
;
73 void skin_buffer_save_position(void)
75 saved_buffer_pos
= buffer_front
;
78 void skin_buffer_restore_position(void)
81 buffer_front
= saved_buffer_pos
;