#include <process.h>
#include <conio.h>
#include <stdio.h>
#include <fcntl.h>
#include <io.h>
#include <sys\types.h>
#include <sys\stat.h>

main ()
{
	int fil, i;
	long fileng, offs;
	unsigned char ch, tempbuf[5];

	puts("");
	puts("DUKSNDFX for Duke Nukem 3D               by Kenneth Silverman (04/26/2000)");
	puts("");
	puts("This program fixes a sound crashing bug in DUKE3D.EXE that occurs on newer");
	puts("   (PCI?) sound cards. If the game crashes immediately upon entering Volume 1,");
	puts("   Level 4 (as well as many other places), then you've found the right program.");
	puts("");
	puts("This program supports these versions of Duke3D:");
	puts("   v1.3d Shareware and Registered versions");
	puts("   v1.5  Atomic Edition");
	puts("");
	puts("Also, be aware that as a side effect, reverberation will be disabled.");
	puts("");
	puts("Do you want to continue with patching DUKE3D.EXE? (Y/N)");

	do
	{
		ch = getch();
	} while ((ch != 'n') && (ch != 'N') && (ch != 'y') && (ch != 'Y') && (ch != 27));
	if ((ch == 'n') || (ch == 'N') || (ch == 27))
	{
		puts("Operation aborted");
		exit(0);
	}

		// DUKE3D.EXE version:   size:    date:     time:   offset:
		// 1.0  Shareware       1066391   01/29/96  13:00   0x74A29  //û
		// 1.1  Shareware       1076339      ?        ?     0x75249  //(according to AshCorv)
		// 1.3d Shareware       1178963      ?        ?     0x89090  //û
		// 1.3d Registered      1179131   04/19/96  13:30   0x89040  //û
		// 1.4  Plutonium Pak   1240151   10/21/96  13:40   0x8F1E1  //(according to Antonio Mignolli)
		// 1.5  Atomic Edition  1246231   12/11/96  13:50   0x8FE51  //û
		// 1.5  Aussie version  1246231      ?        ?     0x8FE51  //(according to Jonathon Fowler)
		// 1.5  Walmart version 1246439   12/11/96  13:50   0x8FE81  //(according to AshCorv)

	if ((fil = open("DUKE3D.EXE",O_BINARY|O_RDWR,S_IREAD)) == -1)
		{ puts("ERROR 1: Can't read DUKE3D.EXE: Make sure it is in the current directory."); exit(0); }
	fileng = filelength(fil);

	offs = -1;
	if (fileng == 1066391) offs = 0x74a29;   //1.0
	if (fileng == 1076339) offs = 0x75249;   //1.1
	if (fileng == 1178963) offs = 0x89090;   //1.3d (s)
	if (fileng == 1179131) offs = 0x89040;   //1.3d (r)
	if (fileng == 1240151) offs = 0x8f1e1;   //1.4
	if (fileng == 1246231) offs = 0x8fe51;   //1.5
	if (fileng == 1246439) offs = 0x8fe81;   //1.5 (Walmart)
	if (offs == -1) { puts("ERROR 2: DUKE3D.EXE unrecognized or not currently supported."); exit(0); }

	lseek(fil,offs,SEEK_SET);
	read(fil,tempbuf,5);
	close(fil);

	if ((tempbuf[0] == 0xb8) && (tempbuf[1] == 0x00) && (tempbuf[2] == 0x00) &&
		 (tempbuf[3] == 0x00) && (tempbuf[4] == 0x00))
	{
		puts("This sound patch has already been applied to DUKE3D.EXE.");
		exit(0);
	}

	if ((tempbuf[0] != 0x2d) || (tempbuf[1] != 0xe8) || (tempbuf[2] != 0x03) ||
		 (tempbuf[3] != 0x00) || (tempbuf[4] != 0x00))
	{
		puts("ERROR 3: DUKE3D.EXE unrecognized, or not currently supported.");
		exit(0);
	}

	if (fileng == 1066391)
	{
		for(i=25;i;i--) puts("");
		puts("Duke Nukem 3D v1.0 (shareware) has been detected:");
		puts("");
		puts("Please be aware that the v1.0 to v1.1 upgrade patch from 3D Realms won't");
		puts("work any more if you apply this patch.");
	}
	if (fileng == 1076339)
	{
		for(i=25;i;i--) puts("");
		puts("Duke Nukem 3D v1.1 (shareware) has been detected:");
		puts("");
		puts("Please be aware that the v1.1 to v1.3d upgrade patch from 3D Realms won't");
		puts("work any more if you apply this patch.");
	}
	if (fileng == 1179131)
	{
		for(i=25;i;i--) puts("");
		puts("Duke Nukem 3D v1.3d (registered) has been detected:");
		puts("");
		puts("Please be aware that using this patch will require you to reinstall from");
		puts("the orginal CD if you purchase the Plutonium PAK at some point in the future");
	}
	if (fileng == 1240151)
	{
		for(i=25;i;i--) puts("");
		puts("Duke Nukem 3D v1.4 (Plutonium Pack) has been detected:");
		puts("");
		puts("It is HIGHLY recommended that you apply the free upgade to the Atomic");
		puts("version (v1.5) BEFORE applying this patch! Should you decide to upgrade");
		puts("to v1.5 in the future, you would have to reinstall v1.3d, upgrade to 1.4,");
		puts("upgrade to v1.5, and finally reinstall this sound patch (YUCK!)");
	}
	if ((fileng == 1066391) || (fileng == 1076339) || (fileng == 1179131) || (fileng == 1240151))
	{
		puts("");
		puts("Proceed anyway? (Y/N)");
		do
		{
			ch = getch();
		} while ((ch != 'n') && (ch != 'N') && (ch != 'y') && (ch != 'Y') && (ch != 27));
		if ((ch == 'n') || (ch == 'N') || (ch == 27))
		{
			puts("Operation aborted");
			exit(0);
		}
	}

		//Actually modify the exe here:
	if ((fil = open("DUKE3D.EXE",O_BINARY|O_RDWR,S_IWRITE)) == -1)
		{ puts("ERROR 4: Can't write to DUKE3D.EXE: Make sure it has write priviledges."); exit(0); }
	lseek(fil,offs,SEEK_SET);
	tempbuf[0] = 0xb8; tempbuf[1] = tempbuf[2] = tempbuf[3] = tempbuf[4] = 0;
	write(fil,tempbuf,5);
	close(fil);
	puts("SUCCESS! DUKE3D.EXE has been patched to prevent the sound crashing bug.");
}