[mirror_ubuntu-bionic-kernel.git] / include / linux / ppp-comp.h

/*
 * ppp-comp.h - Definitions for doing PPP packet compression.
 *
 * Copyright 1994-1998 Paul Mackerras.
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License
 *  version 2 as published by the Free Software Foundation.
 */
#ifndef _NET_PPP_COMP_H
#define _NET_PPP_COMP_H

#include <uapi/linux/ppp-comp.h>


struct module;

/*
 * The following symbols control whether we include code for
 * various compression methods.
 */

#ifndef DO_BSD_COMPRESS
#define DO_BSD_COMPRESS	1	/* by default, include BSD-Compress */
#endif
#ifndef DO_DEFLATE
#define DO_DEFLATE	1	/* by default, include Deflate */
#endif
#define DO_PREDICTOR_1	0
#define DO_PREDICTOR_2	0

/*
 * Structure giving methods for compression/decompression.
 */

struct compressor {
	int	compress_proto;	/* CCP compression protocol number */

	/* Allocate space for a compressor (transmit side) */
	void	*(*comp_alloc) (unsigned char *options, int opt_len);

	/* Free space used by a compressor */
	void	(*comp_free) (void *state);

	/* Initialize a compressor */
	int	(*comp_init) (void *state, unsigned char *options,
			      int opt_len, int unit, int opthdr, int debug);

	/* Reset a compressor */
	void	(*comp_reset) (void *state);

	/* Compress a packet */
	int     (*compress) (void *state, unsigned char *rptr,
			      unsigned char *obuf, int isize, int osize);

	/* Return compression statistics */
	void	(*comp_stat) (void *state, struct compstat *stats);

	/* Allocate space for a decompressor (receive side) */
	void	*(*decomp_alloc) (unsigned char *options, int opt_len);

	/* Free space used by a decompressor */
	void	(*decomp_free) (void *state);

	/* Initialize a decompressor */
	int	(*decomp_init) (void *state, unsigned char *options,
				int opt_len, int unit, int opthdr, int mru,
				int debug);

	/* Reset a decompressor */
	void	(*decomp_reset) (void *state);

	/* Decompress a packet. */
	int	(*decompress) (void *state, unsigned char *ibuf, int isize,
				unsigned char *obuf, int osize);

	/* Update state for an incompressible packet received */
	void	(*incomp) (void *state, unsigned char *ibuf, int icnt);

	/* Return decompression statistics */
	void	(*decomp_stat) (void *state, struct compstat *stats);

	/* Used in locking compressor modules */
	struct module *owner;
	/* Extra skb space needed by the compressor algorithm */
	unsigned int comp_extra;
};

/*
 * The return value from decompress routine is the length of the
 * decompressed packet if successful, otherwise DECOMP_ERROR
 * or DECOMP_FATALERROR if an error occurred.
 * 
 * We need to make this distinction so that we can disable certain
 * useful functionality, namely sending a CCP reset-request as a result
 * of an error detected after decompression.  This is to avoid infringing
 * a patent held by Motorola.
 * Don't you just lurve software patents.
 */

#define DECOMP_ERROR		-1	/* error detected before decomp. */
#define DECOMP_FATALERROR	-2	/* error detected after decomp. */

extern int ppp_register_compressor(struct compressor *);
extern void ppp_unregister_compressor(struct compressor *);
#endif /* _NET_PPP_COMP_H */
Commit	Line	Data
1da177e4 LT	1	/*
	2	* ppp-comp.h - Definitions for doing PPP packet compression.
	3	*
784db3f0	4	* Copyright 1994-1998 Paul Mackerras.
1da177e4	5	*
784db3f0 PM	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License
	8	* version 2 as published by the Free Software Foundation.
1da177e4	9	*/
1da177e4 LT	10	#ifndef _NET_PPP_COMP_H
	11	#define _NET_PPP_COMP_H
	12
607ca46e DH	13	#include <uapi/linux/ppp-comp.h>
607ca46e DH	14
8e4627dd	15
1da177e4 LT	16	struct module;
	17
	18	/*
	19	* The following symbols control whether we include code for
	20	* various compression methods.
	21	*/
	22
	23	#ifndef DO_BSD_COMPRESS
	24	#define DO_BSD_COMPRESS 1 /* by default, include BSD-Compress */
	25	#endif
	26	#ifndef DO_DEFLATE
	27	#define DO_DEFLATE 1 /* by default, include Deflate */
	28	#endif
	29	#define DO_PREDICTOR_1 0
	30	#define DO_PREDICTOR_2 0
	31
	32	/*
	33	* Structure giving methods for compression/decompression.
	34	*/
	35
	36	struct compressor {
	37	int compress_proto; /* CCP compression protocol number */
	38
	39	/* Allocate space for a compressor (transmit side) */
	40	void (comp_alloc) (unsigned char *options, int opt_len);
	41
	42	/* Free space used by a compressor */
	43	void (comp_free) (void state);
	44
	45	/* Initialize a compressor */
	46	int (comp_init) (void state, unsigned char *options,
	47	int opt_len, int unit, int opthdr, int debug);
	48
	49	/* Reset a compressor */
	50	void (comp_reset) (void state);
	51
	52	/* Compress a packet */
	53	int (compress) (void state, unsigned char *rptr,
	54	unsigned char *obuf, int isize, int osize);
	55
	56	/* Return compression statistics */
	57	void (comp_stat) (void state, struct compstat *stats);
	58
	59	/* Allocate space for a decompressor (receive side) */
	60	void (decomp_alloc) (unsigned char *options, int opt_len);
	61
	62	/* Free space used by a decompressor */
	63	void (decomp_free) (void state);
	64
	65	/* Initialize a decompressor */
	66	int (decomp_init) (void state, unsigned char *options,
	67	int opt_len, int unit, int opthdr, int mru,
	68	int debug);
	69
	70	/* Reset a decompressor */
	71	void (decomp_reset) (void state);
	72
	73	/* Decompress a packet. */
	74	int (decompress) (void state, unsigned char *ibuf, int isize,
	75	unsigned char *obuf, int osize);
	76
	77	/* Update state for an incompressible packet received */
	78	void (incomp) (void state, unsigned char *ibuf, int icnt);
	79
80	/* Return decompression statistics */
81	void (decomp_stat) (void state, struct compstat *stats);
82
83	/* Used in locking compressor modules */
84	struct module *owner;
b3f9b92a MD	85	/* Extra skb space needed by the compressor algorithm */
b3f9b92a MD	86	unsigned int comp_extra;
1da177e4 LT	87	};
	88
	89	/*
	90	* The return value from decompress routine is the length of the
	91	* decompressed packet if successful, otherwise DECOMP_ERROR
	92	* or DECOMP_FATALERROR if an error occurred.
	93	*
	94	* We need to make this distinction so that we can disable certain
	95	* useful functionality, namely sending a CCP reset-request as a result
	96	* of an error detected after decompression. This is to avoid infringing
	97	* a patent held by Motorola.
	98	* Don't you just lurve software patents.
	99	*/
	100
	101	#define DECOMP_ERROR -1 /* error detected before decomp. */
	102	#define DECOMP_FATALERROR -2 /* error detected after decomp. */
	103
1da177e4 LT	104	extern int ppp_register_compressor(struct compressor *);
1da177e4 LT	105	extern void ppp_unregister_compressor(struct compressor *);
1da177e4	106	#endif /* _NET_PPP_COMP_H */