1 /*****************************************************************************
2 
3   Filename:     mfifo.h
4 
5   Contents:     header for MFIFO
6 
7   License/Copyright:
8 
9   Copyright (c) 2007, Jan Vidar Berger, Case Labs, Ltd. All rights reserved.
10   email:janvb@caselaboratories.com
11 
12   Redistribution and use in source and binary forms, with or without
13   modification, are permitted provided that the following conditions are
14   met:
15 
16     * Redistributions of source code must retain the above copyright notice,
17 	  this list of conditions and the following disclaimer.
18     * Redistributions in binary form must reproduce the above copyright notice,
19 	  this list of conditions and the following disclaimer in the documentation
20 	  and/or other materials provided with the distribution.
21     * Neither the name of the Case Labs, Ltd nor the names of its contributors
22 	  may be used to endorse or promote products derived from this software
23 	  without specific prior written permission.
24 
25   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
26   AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27   IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28   ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
29   LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30   CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31   SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33   CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34   ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35   POSSIBILITY OF SUCH DAMAGE.
36 *****************************************************************************/
37 #ifndef _MFIFO
38 #define _MFIFO
39 
40 /*****************************************************************************
41 
42   Struct:		MINDEX
43 
44   Description:	Message Index used to index a dynamic size Message FIFO.
45 
46 *****************************************************************************/
47 typedef struct _mindex {
48     int offset;                     /* offset to message in buf             */
49     int size;                       /* size of message in bytes             */
50 } MINDEX;
51 
52 /*****************************************************************************
53 
54   Struct:		MFIFO
55 
56   Description:	Message FIFO. Provides a dynamic sized message based FIFO
57 				queue.
58 
59 *****************************************************************************/
60 typedef struct {
61 	int first;                      /* first out                            */
62 	int last;                       /* last in + 1                          */
63 	int bsize;                      /* buffer size                          */
64 	unsigned char *buf;             /* ptr to start of buffer               */
65 	int ixsize;                     /* index size                           */
66 	MINDEX ix[1];                   /* message index                        */
67 } MFIFO;
68 
69 /*****************************************************************************
70   Function prototypes.
71 *****************************************************************************/
72 int MFIFOCreate(unsigned char *buf, int size, int index);
73 void MFIFOClear(unsigned char * buf);
74 int MFIFOGetLBOffset(unsigned char *buf);
75 int MFIFOGetFBOffset(unsigned char *buf);
76 void MFIFOWriteIX(unsigned char *buf, unsigned char *mes, int size, int ix, int off);
77 int MFIFOWriteMes(unsigned char *buf, unsigned char *mes, int size);
78 unsigned char * MFIFOGetMesPtr(unsigned char *buf, int *size);
79 void MFIFOKillNext(unsigned char *buf);
80 
81 unsigned char * MFIFOGetMesPtrOffset(unsigned char *buf, int *size, const int pos);
82 int MFIFOGetMesCount(unsigned char *buf);
83 int MFIFOWriteMesOverwrite(unsigned char *buf, unsigned char *mes, int size);
84 
85 #endif
86