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static char _[] = "@(#)endian.c 5.18 93/07/30 16:40:17, Srini, AMD.";

/******************************************************************************

 * Copyright 1991 Advanced Micro Devices, Inc.

 *

 * This software is the property of Advanced Micro Devices, Inc  (AMD)  which

 * specifically  grants the user the right to modify, use and distribute this

 * software provided this notice is not removed or altered.  All other rights

 * are reserved by AMD.

 *

 * AMD MAKES NO WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, WITH REGARD TO THIS

 * SOFTWARE.  IN NO EVENT SHALL AMD BE LIABLE FOR INCIDENTAL OR CONSEQUENTIAL

 * DAMAGES IN CONNECTION WITH OR ARISING FROM THE FURNISHING, PERFORMANCE, OR

 * USE OF THIS SOFTWARE.

 *

 * So that all may benefit from your experience, please report  any  problems

 * or  suggestions about this software to the 29K Technical Support Center at

 * 800-29-29-AMD (800-292-9263) in the USA, or 0800-89-1131  in  the  UK,  or

 * 0031-11-1129 in Japan, toll free.  The direct dial number is 512-462-4118.

 *

 * Advanced Micro Devices, Inc.

 * 29K Support Products

 * Mail Stop 573

 * 5900 E. Ben White Blvd.

 * Austin, TX 78741

 * 800-292-9263

 *****************************************************************************

 *      Engineer: Srini Subramanian.

 *****************************************************************************

 **

 **       This module implements the endian conversion routines used by MONTIP.

 **

 *****************************************************************************

 */

#include <stdio.h>

#include <ctype.h>

#include  "messages.h"

#ifdef MSDOS

#include <string.h>

#else

#include <string.h>

#endif  /* MSDOS */

/* Functions */

void  tip_convert32 PARAMS((BYTE *));

void  tip_convert16 PARAMS((BYTE *));

/*

** This function is used to convert the endian of messages.

** Both host to target and target to host messages can be

** converted using this function.

**

** Note that all monitor messages have a header consisting of

** a 32 bit message number and a 32 bit size.  Following this

** may be one or more 32 bit parameters.  And folowing these

** parameters may be an array of bytes.

**

** This function converts the endian of the header and any

** parameters.  It is not necessary to convert the array of

** bytes.

**

** Note that the use of 32 bit parameters makes this conversion

** routine fairly simple.

*/

void

endian_cvt(msg_buf, direction)

   union  msg_t  *msg_buf;

   int    direction;

   {

   INT32  i;

   BYTE  *byte;

   INT32  code;

   INT32  length;

   /*

   ** If incoming message, convert endian, then get message

   ** type and message length.  If outgoing message, get

   ** message type and message length, then convert endian.

   */

   if ((direction != OUTGOING_MSG) &&

       (direction != INCOMING_MSG))

      return;

   if (direction == OUTGOING_MSG) {

      code = (msg_buf->generic_msg).code;

      length = (msg_buf->generic_msg).length;

      }

   /* Change endian of "code" field */

   tip_convert32((BYTE *) &(msg_buf->generic_msg).code);

   /* Change endian of "length" field */

   tip_convert32((BYTE *) &(msg_buf->generic_msg).length);

   if (direction == INCOMING_MSG) {

      code = (msg_buf->generic_msg).code;

      length = (msg_buf->generic_msg).length;

      }

   /*

   ** Some messages, notably WRITE_REQ, FILL, READ

   ** and TRACE have data following the message

   ** parameters.  Since we don't want to swap bytes

   ** in the data array, we need to get the number of

   ** of bytes taken up by the parameters.  This is

   ** still better than having to find ALL of the

   ** message lengths statically.

   */

   if (code == WRITE_REQ)

      length = msg_length(WRITE_REQ);

   else

   if (code == FILL)

      length = MSG_LENGTH(struct fill_msg_t);

   else

   if (code == READ_ACK)

      length = MSG_LENGTH(struct read_ack_msg_t);

   else

   if (code == CHANNEL1)

      length = MSG_LENGTH(struct channel1_msg_t);

   else

   if (code == CHANNEL2)

      length = MSG_LENGTH(struct channel2_msg_t);

   else

   if (code == CHANNEL0)

      length = MSG_LENGTH(struct channel0_msg_t);

   else

   if (code == STDIN_NEEDED_ACK)

      length = MSG_LENGTH(struct stdin_needed_ack_msg_t);

   /* Convert message parameters */

   byte = (BYTE *) &(msg_buf->generic_msg).byte;

   for (i=0; i<(length/sizeof(INT32)); i=i+1) {

      tip_convert32(byte);

      byte = byte + sizeof(INT32);

      }

   }   /* end endian_cvt */

/*

** This function is used to swap the bytes in a 32 bit

** word.  This will convert "little endian" (IBM-PC / Intel)

** words to "big endian" (Sun / Motorola) words.

*/

void

tip_convert32(byte)

   BYTE *byte;

   {

   BYTE temp;

   temp = byte[0];  /* Swap bytes 0 and 3 */

   byte[0] = byte[3];

   byte[3] = temp;

   temp = byte[1];  /* Swap bytes 1 and 2 */

   byte[1] = byte[2];

   byte[2] = temp;

   }   /* end tip_convert32() */

/*

** This function is used to swap the bytes in a 16 bit

** word.  This will convert "little endian" (IBM-PC / Intel)

** half words to "big endian" (Sun / Motorola) half words.

*/

void

tip_convert16(byte)

   BYTE *byte;

   {

   BYTE temp;

   temp = byte[0];  /* Swap bytes 0 and 1 */

   byte[0] = byte[1];

   byte[1] = temp;

   }   /* end tip_convert16() */