usr.bin/tn3270/api/api_exch.h

   1 /*      $NetBSD: api_exch.h,v 1.6 2002/06/13 23:41:16 wiz Exp $ */
   2
   3 /*-
   4  * Copyright (c) 1988 The Regents of the University of California.
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  *      from: @(#)api_exch.h    4.2 (Berkeley) 4/26/91
  32  */
  33
  34 /*
  35  * This file describes the structures passed back and forth
  36  * between the API client and API server on a Unix-based
  37  * tn3270 implementation.
  38  */
  39
  40 /*
  41  * The following are the low-level opcodes exchanged between the
  42  * two sides.  These are designed to allow for type, sequence number,
  43  * and direction checking.
  44  *
  45  * We enforce conversation flow.  There are three states: CONTENTION,
  46  * SEND, and RECEIVE.  Both sides start in CONTENTION.
  47  * We never leave RECEIVE state without first reading a TURNAROUND
  48  * opcode.  We never leave SEND state without first writing a TURNAROUND
  49  * opcode.  This scheme ensures that we always have conversation flowing
  50  * in a synchronized direction (or detect an application error), and that
  51  * we never hang with both sides trying to read from the "wire".
  52  *
  53  * State        event                   action
  54  *
  55  * CONTENTION   read request            send TURNAROUND
  56  *                                      read RTS
  57  *                                      enter RECEIVE
  58  * CONTENTION   write request           send RTS
  59  *                                      read TURNAROUND
  60  *                                      enter SEND
  61  *
  62  * RECEIVE      read request            read whatever
  63  * RECEIVE      write request           read TURNAROUND
  64  *
  65  * SEND         read request            send TURNAROUND
  66  * SEND         write                   write whatever
  67  */
  68
  69 #define EXCH_EXCH_COMMAND       0       /* The following is a command */
  70 #define EXCH_EXCH_TURNAROUND    1       /* Your turn to send */
  71 #define EXCH_EXCH_RTS           2       /* Request to send */
  72 #define EXCH_EXCH_TYPE          3       /* The following is a type */
  73
  74 struct exch_exch {
  75     char
  76         opcode;                 /* COMMAND, TURNAROUND, or TYPE */
  77     unsigned char
  78         my_sequence,            /* 0-ff, initially zero */
  79         your_sequence,          /* 0-ff, initially zero */
  80         command_or_type;        /* Application level command or type */
  81     unsigned short
  82         length;                 /* The length of any following data */
  83 };
  84
  85 /*
  86  * The following are the command codes which the higher level protocols
  87  * send and receive.
  88  */
  89
  90 #define EXCH_CMD_ASSOCIATE      0       /* Connect [client->server] */
  91         /*
  92          * struct storage_desc
  93          * char key[]
  94          */
  95 #define EXCH_CMD_DISASSOCIATE   1       /* Disconnect [client->server] */
  96 #define EXCH_CMD_SEND_AUTH      2       /* Send password [server->client] */
  97         /*
  98          * struct storage_desc
  99          * char prompt[]
 100          * struct storage_desc
 101          * char seed[]
 102          */
 103 #define EXCH_CMD_AUTH           3       /* Authorization [client->server] */
 104         /*
 105          * struct storage_desc
 106          * char authenticator[]
 107          */
 108 #define EXCH_CMD_ASSOCIATED     4       /* Connected [server->client] */
 109 #define EXCH_CMD_REJECTED       5       /* Too bad [server->client] */
 110         /*
 111          * struct storage_desc
 112          * char message[]
 113          */
 114
 115 #define EXCH_CMD_REQUEST        6       /* A request [client->server] */
 116         /* struct regs,
 117          * struct sregs,
 118          * struct storage_desc
 119          * char bytes[]
 120          */
 121 #define EXCH_CMD_GIMME          7       /* Send storage [server->client] */
 122         /*
 123          * struct storage_desc
 124          */
 125 #define EXCH_CMD_HEREIS         8       /* Here is storage [BOTH WAYS] */
 126         /*
 127          * struct storage_desc
 128          * char bytes[]
 129          */
 130 #define EXCH_CMD_REPLY          9       /* End of discussion */
 131         /*
 132          * struct regs,
 133          * struct sregs,
 134          */
 135
 136 /*
 137  * The following are typed parameters sent across the wire.
 138  *
 139  * This should be done much more generally, with some form of
 140  * XDR or mapped conversation ability.
 141  */
 142
 143 #define EXCH_TYPE_REGS          0
 144 #define EXCH_TYPE_SREGS         1
 145 #define EXCH_TYPE_STORE_DESC    2
 146 #define EXCH_TYPE_BYTES         3
 147
 148 /*
 149  * each parameter that comes over looks like:
 150  *
 151  *      char                    type of following
 152  *      short (2 bytes)         length of following (network byte order)
 153  *      following
 154  */
 155
 156 struct storage_descriptor {
 157     long        location;       /* In network byte order */
 158     short       length;         /* In network byte order */
 159 };
 160
 161 int api_exch_nextcommand(void);
 162 int api_exch_incommand(int);
 163 int api_exch_outcommand(int);
 164 int api_exch_outtype(int, int , const char *);
 165 int api_exch_intype(int, int , char *);
 166 int api_exch_flush(void);
 167 int api_exch_init(int, char *);