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Member "tn3270-5.2.0-glibc/tn3270/api/api_exch.h" of archive tn3270-5.2.0-glibc.tgz:

    1 /*
    2  * Copyright (c) 1988 Regents of the University of California.
    3  * All rights reserved.
    4  *
    5  * Redistribution and use in source and binary forms are permitted
    6  * provided that the above copyright notice and this paragraph are
    7  * duplicated in all such forms and that any documentation,
    8  * advertising materials, and other materials related to such
    9  * distribution and use acknowledge that the software was developed
   10  * by the University of California, Berkeley.  The name of the
   11  * University may not be used to endorse or promote products derived
   12  * from this software without specific prior written permission.
   13  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
   14  * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
   15  * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
   16  *
   17  *	@(#)api_exch.h	4.1 (Berkeley) 12/4/88
   18  */
   19 
   20 /*
   21  * This file describes the structures passed back and forth
   22  * between the API client and API server on a Unix-based
   23  * tn3270 implementation.
   24  */
   25 
   26 /*
   27  * The following are the low-level opcodes exchanged between the
   28  * two sides.  These are designed to allow for type, sequence number,
   29  * and direction checking.
   30  *
   31  * We enforce conversation flow.  There are three states: CONTENTION,
   32  * SEND, and RECEIVE.  Both sides start in CONTENTION.
   33  * We never leave RECEIVE state without first reading a TURNAROUND
   34  * opcode.  We never leave SEND state without first writing a TURNAROUND
   35  * opcode.  This scheme ensures that we always have conversation flowing
   36  * in a synchronized direction (or detect an application error), and that
   37  * we never hang with both sides trying to read from the "wire".
   38  *
   39  * State	event			action
   40  *
   41  * CONTENTION	read request		send TURNAROUND
   42  *					read RTS
   43  *					enter RECEIVE
   44  * CONTENTION	write request		send RTS
   45  *					read TURNAROUND
   46  *					enter SEND
   47  *
   48  * RECEIVE	read request		read whatever
   49  * RECEIVE	write request		read TURNAROUND
   50  *
   51  * SEND		read request		send TURNAROUND
   52  * SEND		write			write whatever
   53  */
   54 
   55 #define	EXCH_EXCH_COMMAND	0	/* The following is a command */
   56 #define	EXCH_EXCH_TURNAROUND	1	/* Your turn to send */
   57 #define	EXCH_EXCH_RTS		2	/* Request to send */
   58 #define	EXCH_EXCH_TYPE		3	/* The following is a type */
   59 
   60 struct exch_exch {
   61     char
   62 	opcode;			/* COMMAND, TURNAROUND, or TYPE */
   63     unsigned char
   64 	my_sequence,		/* 0-ff, initially zero */
   65 	your_sequence,		/* 0-ff, initially zero */
   66 	command_or_type;	/* Application level command or type */
   67     unsigned short
   68 	length;			/* The length of any following data */
   69 };
   70 
   71 /*
   72  * The following are the command codes which the higher level protocols
   73  * send and receive.
   74  */
   75 
   76 #define	EXCH_CMD_ASSOCIATE	0	/* Connect [client->server] */
   77 	/*
   78 	 * struct storage_desc
   79 	 * char key[]
   80 	 */
   81 #define	EXCH_CMD_DISASSOCIATE	1	/* Disconnect [client->server] */
   82 #define	EXCH_CMD_SEND_AUTH	2	/* Send password [server->client] */
   83 	/*
   84 	 * struct storage_desc
   85 	 * char prompt[]
   86 	 * struct storage_desc
   87 	 * char seed[]
   88 	 */
   89 #define	EXCH_CMD_AUTH		3	/* Authorization [client->server] */
   90 	/*
   91 	 * struct storage_desc
   92 	 * char authenticator[]
   93 	 */
   94 #define	EXCH_CMD_ASSOCIATED	4	/* Connected [server->client] */
   95 #define	EXCH_CMD_REJECTED	5	/* Too bad [server->client] */
   96 	/*
   97 	 * struct storage_desc
   98 	 * char message[]
   99 	 */
  100 
  101 #define	EXCH_CMD_REQUEST	6	/* A request [client->server] */
  102 	/* struct regs,
  103 	 * struct sregs,
  104 	 * struct storage_desc
  105 	 * char bytes[]
  106 	 */
  107 #define	EXCH_CMD_GIMME		7	/* Send storage [server->client] */
  108 	/*
  109 	 * struct storage_desc
  110 	 */
  111 #define	EXCH_CMD_HEREIS		8	/* Here is storage [BOTH WAYS] */
  112 	/*
  113 	 * struct storage_desc
  114 	 * char bytes[]
  115 	 */
  116 #define	EXCH_CMD_REPLY		9	/* End of discussion */
  117 	/*
  118 	 * struct regs,
  119 	 * struct sregs,
  120 	 */
  121 
  122 /*
  123  * The following are typed parameters sent across the wire.
  124  *
  125  * This should be done much more generally, with some form of
  126  * XDR or mapped conversation ability.
  127  */
  128 
  129 #define	EXCH_TYPE_REGS		0
  130 #define	EXCH_TYPE_SREGS		1
  131 #define	EXCH_TYPE_STORE_DESC	2
  132 #define	EXCH_TYPE_BYTES		3
  133 
  134 /*
  135  * each parameter that comes over looks like:
  136  *
  137  *	char			type of following
  138  *	short (2 bytes)		length of following (network byte order)
  139  *	following
  140  */
  141 
  142 struct storage_descriptor {
  143     long	location;	/* In network byte order */
  144     short	length;		/* In network byte order */
  145 };