Where Online Learning is simpler!

The C and C++ Include Header Files

cat -n /usr/include/linux/ppp-comp.h

     1	/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
     2	/*
     3	 * ppp-comp.h - Definitions for doing PPP packet compression.
     4	 *
     5	 * Copyright 1994-1998 Paul Mackerras.
     6	 *
     7	 *  This program is free software; you can redistribute it and/or
     8	 *  modify it under the terms of the GNU General Public License
     9	 *  version 2 as published by the Free Software Foundation.
    10	 */
    11	#ifndef _NET_PPP_COMP_H
    12	#define _NET_PPP_COMP_H
    13	
    14	
    15	/*
    16	 * CCP codes.
    17	 */
    18	
    19	#define CCP_CONFREQ	1
    20	#define CCP_CONFACK	2
    21	#define CCP_TERMREQ	5
    22	#define CCP_TERMACK	6
    23	#define CCP_RESETREQ	14
    24	#define CCP_RESETACK	15
    25	
    26	/*
    27	 * Max # bytes for a CCP option
    28	 */
    29	
    30	#define CCP_MAX_OPTION_LENGTH	32
    31	
    32	/*
    33	 * Parts of a CCP packet.
    34	 */
    35	
    36	#define CCP_CODE(dp)		((dp)[0])
    37	#define CCP_ID(dp)		((dp)[1])
    38	#define CCP_LENGTH(dp)		(((dp)[2] << 8) + (dp)[3])
    39	#define CCP_HDRLEN		4
    40	
    41	#define CCP_OPT_CODE(dp)	((dp)[0])
    42	#define CCP_OPT_LENGTH(dp)	((dp)[1])
    43	#define CCP_OPT_MINLEN		2
    44	
    45	/*
    46	 * Definitions for BSD-Compress.
    47	 */
    48	
    49	#define CI_BSD_COMPRESS		21	/* config. option for BSD-Compress */
    50	#define CILEN_BSD_COMPRESS	3	/* length of config. option */
    51	
    52	/* Macros for handling the 3rd byte of the BSD-Compress config option. */
    53	#define BSD_NBITS(x)		((x) & 0x1F)	/* number of bits requested */
    54	#define BSD_VERSION(x)		((x) >> 5)	/* version of option format */
    55	#define BSD_CURRENT_VERSION	1		/* current version number */
    56	#define BSD_MAKE_OPT(v, n)	(((v) << 5) | (n))
    57	
    58	#define BSD_MIN_BITS		9	/* smallest code size supported */
    59	#define BSD_MAX_BITS		15	/* largest code size supported */
    60	
    61	/*
    62	 * Definitions for Deflate.
    63	 */
    64	
    65	#define CI_DEFLATE		26	/* config option for Deflate */
    66	#define CI_DEFLATE_DRAFT	24	/* value used in original draft RFC */
    67	#define CILEN_DEFLATE		4	/* length of its config option */
    68	
    69	#define DEFLATE_MIN_SIZE	9
    70	#define DEFLATE_MAX_SIZE	15
    71	#define DEFLATE_METHOD_VAL	8
    72	#define DEFLATE_SIZE(x)		(((x) >> 4) + 8)
    73	#define DEFLATE_METHOD(x)	((x) & 0x0F)
    74	#define DEFLATE_MAKE_OPT(w)	((((w) - 8) << 4) + DEFLATE_METHOD_VAL)
    75	#define DEFLATE_CHK_SEQUENCE	0
    76	
    77	/*
    78	 * Definitions for MPPE.
    79	 */
    80	
    81	#define CI_MPPE                18      /* config option for MPPE */
    82	#define CILEN_MPPE              6      /* length of config option */
    83	
    84	/*
    85	 * Definitions for other, as yet unsupported, compression methods.
    86	 */
    87	
    88	#define CI_PREDICTOR_1		1	/* config option for Predictor-1 */
    89	#define CILEN_PREDICTOR_1	2	/* length of its config option */
    90	#define CI_PREDICTOR_2		2	/* config option for Predictor-2 */
    91	#define CILEN_PREDICTOR_2	2	/* length of its config option */
    92	
    93	
    94	#endif /* _NET_PPP_COMP_H */