/*
 * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_HEADER_START@
 * 
 * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
 * Please see the License for the specific language governing rights and
 * limitations under the License.
 * 
 * @APPLE_LICENSE_HEADER_END@
 */

#include "libsaio.h"

/*
 * Convert zero-based linear address to far pointer.
 */
#define GET_FP(x)   ( (((x) & 0xffff0000) << (16 - 4)) | ((x) & 0xffff) )

/*==========================================================================
 * Issue a command to the network loader.
 *
 * The 'cmd' command structure should be allocated on the stack to
 * ensure that it resides within the addressable range for the
 * network loader, which runs in real mode.
 */
static UInt32 nbp(nbpCommandCode_t code, nbpCommand_u * cmd)
{
	loader(code, GET_FP((UInt32) cmd));

	// Must re-enable the A20 address line, the PXE firmware will
	// disable the A20 line control.
	//
	enableA20();

	return cmd->header.status;
}

/*==========================================================================
 * Unload Base Code Stack command.
 */
UInt32 nbpUnloadBaseCode()
{
    return nbp(nbpCommandUnloadBaseCode, (nbpCommand_u *) 0);
}

/*==========================================================================
 * TFTP Read File command.
 */
static long NBPLoadFile(CICell ih, char * filePath)
{
    nbpCommandTFTPReadFile_s  cmd;
	UInt32                    ret;

	strcpy(cmd.filename, filePath);
	cmd.status     = nbpStatusFailed;
	cmd.bufferSize = TFTP_LEN;
	cmd.buffer     = TFTP_ADDR;

	verbose("Loading file: %s\n", filePath);

	ret = nbp(nbpCommandTFTPReadFile, (nbpCommand_u *) &cmd);

    return (ret == nbpStatusSuccess) ? (long)cmd.bufferSize : -1;
}

/*==========================================================================
 * GetDirEntry is not supported.
 */
static long NBPGetDirEntry(CICell ih, char * dirPath, long * dirIndex,
                           char ** name, long * flags, long * time)
{
    return -1;
}

//==========================================================================

static void NBPGetDescription(CICell ih, char * str, long strMaxLen)
{
    sprintf( str, "Ethernet PXE Client" );
}

//==========================================================================

BVRef nbpScanBootVolumes( int biosdev, int * countPtr )
{
    static BVRef gNetBVR = NULL;

    if ( countPtr ) *countPtr = 1;

    if ( !gNetBVR )
    {
        gNetBVR = malloc( sizeof(*gNetBVR) );
        if ( gNetBVR )
        {
            bzero(gNetBVR, sizeof(*gNetBVR));
            gNetBVR->biosdev = biosdev;
            gNetBVR->flags   = kBVFlagPrimary | kBVFlagNativeBoot;
            gNetBVR->description = NBPGetDescription;
            gNetBVR->fs_loadfile = NBPLoadFile;
            gNetBVR->fs_getdirentry = NBPGetDirEntry;
        }
    }
    return gNetBVR;
}