diff options
Diffstat (limited to 'include/linux/ppp-comp.h')
| -rw-r--r-- | include/linux/ppp-comp.h | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/include/linux/ppp-comp.h b/include/linux/ppp-comp.h new file mode 100644 index 000000000..4ea1d377e --- /dev/null +++ b/include/linux/ppp-comp.h @@ -0,0 +1,106 @@ +/* + * 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 */ |