1 /*
2  * slip.h	Define the SLIP device driver interface and constants.
3  *
4  * NOTE:	THIS FILE WILL BE MOVED TO THE LINUX INCLUDE DIRECTORY
5  *		AS SOON AS POSSIBLE!
6  *
7  * Version:	@(#)slip.h	1.2.0	03/28/93
8  *
9  * Fixes:
10  *		Alan Cox	: 	Added slip mtu field.
11  *		Matt Dillon	:	Printable slip (borrowed from net2e)
12  *		Alan Cox	:	Added SL_SLIP_LOTS
13  *	Dmitry Gorodchanin	:	A lot of changes in the 'struct slip'
14  *	Dmitry Gorodchanin	:	Added CSLIP statistics.
15  *	Stanislav Voronyi	:	Make line checking as created by
16  *					Igor Chechik, RELCOM Corp.
17  *	Craig Schlenter		:	Fixed #define bug that caused
18  *					CSLIP telnets to hang in 1.3.61-6
19  *
20  * Author:	Fred N. van Kempen, <waltje@uwalt.nl.mugnet.org>
21  */
22 #ifndef _LINUX_SLIP_H
23 #define _LINUX_SLIP_H
24 
25 
26 #if defined(CONFIG_INET) && defined(CONFIG_SLIP_COMPRESSED)
27 # define SL_INCLUDE_CSLIP
28 #endif
29 
30 #ifdef SL_INCLUDE_CSLIP
31 # define SL_MODE_DEFAULT SL_MODE_ADAPTIVE
32 #else
33 # define SL_MODE_DEFAULT SL_MODE_SLIP
34 #endif
35 
36 /* SLIP configuration. */
37 #define SL_NRUNIT	256		/* MAX number of SLIP channels;
38 					   This can be overridden with
39 					   insmod -oslip_maxdev=nnn	*/
40 #define SL_MTU		296		/* 296; I am used to 600- FvK	*/
41 
42 /* SLIP protocol characters. */
43 #define END             0300		/* indicates end of frame	*/
44 #define ESC             0333		/* indicates byte stuffing	*/
45 #define ESC_END         0334		/* ESC ESC_END means END 'data'	*/
46 #define ESC_ESC         0335		/* ESC ESC_ESC means ESC 'data'	*/
47 
48 
49 struct slip {
50   int			magic;
51 
52   /* Various fields. */
53   struct tty_struct	*tty;		/* ptr to TTY structure		*/
54   struct net_device	*dev;		/* easy for intr handling	*/
55   spinlock_t		lock;
56 
57 #ifdef SL_INCLUDE_CSLIP
58   struct slcompress	*slcomp;	/* for header compression 	*/
59   unsigned char		*cbuff;		/* compression buffer		*/
60 #endif
61 
62   /* These are pointers to the malloc()ed frame buffers. */
63   unsigned char		*rbuff;		/* receiver buffer		*/
64   int                   rcount;         /* received chars counter       */
65   unsigned char		*xbuff;		/* transmitter buffer		*/
66   unsigned char         *xhead;         /* pointer to next byte to XMIT */
67   int                   xleft;          /* bytes left in XMIT queue     */
68 
69   /* SLIP interface statistics. */
70 #ifdef SL_INCLUDE_CSLIP
71   unsigned long		tx_compressed;
72   unsigned long		rx_compressed;
73   unsigned long		tx_misses;
74 #endif
75   /* Detailed SLIP statistics. */
76 
77   int			mtu;		/* Our mtu (to spot changes!)   */
78   int                   buffsize;       /* Max buffers sizes            */
79 
80 #ifdef CONFIG_SLIP_MODE_SLIP6
81   int			xdata, xbits;	/* 6 bit slip controls 		*/
82 #endif
83 
84   unsigned long		flags;		/* Flag values/ mode etc	*/
85 #define SLF_INUSE	0		/* Channel in use               */
86 #define SLF_ESCAPE	1               /* ESC received                 */
87 #define SLF_ERROR	2               /* Parity, etc. error           */
88 #define SLF_KEEPTEST	3		/* Keepalive test flag		*/
89 #define SLF_OUTWAIT	4		/* is outpacket was flag	*/
90 
91   unsigned char		mode;		/* SLIP mode			*/
92   unsigned char		leased;
93   dev_t			line;
94   pid_t			pid;
95 #define SL_MODE_SLIP	0
96 #define SL_MODE_CSLIP	1
97 #define SL_MODE_SLIP6	2		/* Matt Dillon's printable slip */
98 #define SL_MODE_CSLIP6	(SL_MODE_SLIP6|SL_MODE_CSLIP)
99 #define SL_MODE_AX25	4
100 #define SL_MODE_ADAPTIVE 8
101 #ifdef CONFIG_SLIP_SMART
102   unsigned char		outfill;	/* # of sec between outfill packet */
103   unsigned char		keepalive;	/* keepalive seconds		*/
104   struct timer_list	outfill_timer;
105   struct timer_list	keepalive_timer;
106 #endif
107 };
108 
109 #define SLIP_MAGIC 0x5302
110 
111 #endif	/* _LINUX_SLIP.H */
112