AppleWin/source/DiskImage.cpp

927 lines
31 KiB
C++

/*
AppleWin : An Apple //e emulator for Windows
Copyright (C) 1994-1996, Michael O'Brien
Copyright (C) 1999-2001, Oliver Schmidt
Copyright (C) 2002-2005, Tom Charlesworth
Copyright (C) 2006-2007, Tom Charlesworth, Michael Pohoreski
AppleWin is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
AppleWin is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with AppleWin; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/* Description: Disk Image
*
* Author: Various
*/
#include "StdAfx.h"
#pragma hdrstop
/* DO logical order 0 1 2 3 4 5 6 7 8 9 A B C D E F */
/* physical order 0 D B 9 7 5 3 1 E C A 8 6 4 2 F */
/* PO logical order 0 E D C B A 9 8 7 6 5 4 3 2 1 F */
/* physical order 0 2 4 6 8 A C E 1 3 5 7 9 B D F */
typedef struct _imageinforec {
TCHAR filename[MAX_PATH];
DWORD format;
HANDLE file;
DWORD offset;
BOOL writeprotected;
DWORD headersize;
LPBYTE header;
BOOL validtrack[TRACKS];
} imageinforec, *imageinfoptr;
typedef BOOL (*boottype )(imageinfoptr);
typedef DWORD (*detecttype)(LPBYTE,DWORD);
typedef void (*readtype )(imageinfoptr,int,int,LPBYTE,int *);
typedef void (*writetype )(imageinfoptr,int,int,LPBYTE,int);
BOOL AplBoot (imageinfoptr ptr);
DWORD AplDetect (LPBYTE imageptr, DWORD imagesize);
DWORD DoDetect (LPBYTE imageptr, DWORD imagesize);
void DoRead (imageinfoptr ptr, int track, int quartertrack, LPBYTE trackimagebuffer, int *nibbles);
void DoWrite (imageinfoptr ptr, int track, int quartertrack, LPBYTE trackimage, int nibbles);
DWORD IieDetect (LPBYTE imageptr, DWORD imagesize);
void IieRead (imageinfoptr ptr, int track, int quartertrack, LPBYTE trackimagebuffer, int *nibbles);
void IieWrite (imageinfoptr ptr, int track, int quartertrack, LPBYTE trackimage, int nibbles);
DWORD Nib1Detect (LPBYTE imageptr, DWORD imagesize);
void Nib1Read (imageinfoptr ptr, int track, int quartertrack, LPBYTE trackimagebuffer, int *nibbles);
void Nib1Write (imageinfoptr ptr, int track, int quartertrack, LPBYTE trackimage, int nibbles);
DWORD Nib2Detect (LPBYTE imageptr, DWORD imagesize);
void Nib2Read (imageinfoptr ptr, int track, int quartertrack, LPBYTE trackimagebuffer, int *nibbles);
void Nib2Write (imageinfoptr ptr, int track, int quartertrack, LPBYTE trackimage, int nibbles);
DWORD PoDetect (LPBYTE imageptr, DWORD imagesize);
void PoRead (imageinfoptr ptr, int track, int quartertrack, LPBYTE trackimagebuffer, int *nibbles);
void PoWrite (imageinfoptr ptr, int track, int quartertrack, LPBYTE trackimage, int nibbles);
BOOL PrgBoot (imageinfoptr ptr);
DWORD PrgDetect (LPBYTE imageptr, DWORD imagesize);
typedef struct _imagetyperec {
LPCTSTR createexts;
LPCTSTR rejectexts;
detecttype detect;
boottype boot;
readtype read;
writetype write;
} imagetyperec, *imagetypeptr;
static imagetyperec imagetype[IMAGETYPES] = {{TEXT(".prg"),
TEXT(".do;.dsk;.iie;.nib;.po"),
PrgDetect,
PrgBoot,
NULL,
NULL},
{TEXT(".do;.dsk"),
TEXT(".nib;.iie;.po;.prg"),
DoDetect,
NULL,
DoRead,
DoWrite},
{TEXT(".po"),
TEXT(".do;.iie;.nib;.prg"),
PoDetect,
NULL,
PoRead,
PoWrite},
{TEXT(".apl"),
TEXT(".do;.dsk;.iie;.nib;.po"),
AplDetect,
AplBoot,
NULL,
NULL},
{TEXT(".nib"),
TEXT(".do;.iie;.po;.prg"),
Nib1Detect,
NULL,
Nib1Read,
Nib1Write},
{TEXT(".nb2"),
TEXT(".do;.iie;.po;.prg"),
Nib2Detect,
NULL,
Nib2Read,
Nib2Write},
{TEXT(".iie"),
TEXT(".do.;.nib;.po;.prg"),
IieDetect,
NULL,
IieRead,
IieWrite}};
static BYTE diskbyte[0x40] = {0x96,0x97,0x9A,0x9B,0x9D,0x9E,0x9F,0xA6,
0xA7,0xAB,0xAC,0xAD,0xAE,0xAF,0xB2,0xB3,
0xB4,0xB5,0xB6,0xB7,0xB9,0xBA,0xBB,0xBC,
0xBD,0xBE,0xBF,0xCB,0xCD,0xCE,0xCF,0xD3,
0xD6,0xD7,0xD9,0xDA,0xDB,0xDC,0xDD,0xDE,
0xDF,0xE5,0xE6,0xE7,0xE9,0xEA,0xEB,0xEC,
0xED,0xEE,0xEF,0xF2,0xF3,0xF4,0xF5,0xF6,
0xF7,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF};
static BYTE sectornumber[3][0x10] = {{0x00,0x08,0x01,0x09,0x02,0x0A,0x03,0x0B,
0x04,0x0C,0x05,0x0D,0x06,0x0E,0x07,0x0F},
{0x00,0x07,0x0E,0x06,0x0D,0x05,0x0C,0x04,
0x0B,0x03,0x0A,0x02,0x09,0x01,0x08,0x0F},
{0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00}};
static LPBYTE workbuffer = NULL;
/****************************************************************************
*
* NIBBLIZATION FUNCTIONS
*
***/
//===========================================================================
LPBYTE Code62 (int sector) {
// CONVERT THE 256 8-BIT BYTES INTO 342 6-BIT BYTES, WHICH WE STORE
// STARTING AT 4K INTO THE WORK BUFFER.
{
LPBYTE sectorbase = workbuffer+(sector << 8);
LPBYTE resultptr = workbuffer+0x1000;
BYTE offset = 0xAC;
while (offset != 0x02) {
BYTE value = 0;
#define ADDVALUE(a) value = (value << 2) | \
(((a) & 0x01) << 1) | \
(((a) & 0x02) >> 1)
ADDVALUE(*(sectorbase+offset)); offset -= 0x56;
ADDVALUE(*(sectorbase+offset)); offset -= 0x56;
ADDVALUE(*(sectorbase+offset)); offset -= 0x53;
#undef ADDVALUE
*(resultptr++) = value << 2;
}
*(resultptr-2) &= 0x3F;
*(resultptr-1) &= 0x3F;
int loop = 0;
while (loop < 0x100)
*(resultptr++) = *(sectorbase+(loop++));
}
// EXCLUSIVE-OR THE ENTIRE DATA BLOCK WITH ITSELF OFFSET BY ONE BYTE,
// CREATING A 343RD BYTE WHICH IS USED AS A CHECKSUM. STORE THE NEW
// BLOCK OF 343 BYTES STARTING AT 5K INTO THE WORK BUFFER.
{
BYTE savedval = 0;
LPBYTE sourceptr = workbuffer+0x1000;
LPBYTE resultptr = workbuffer+0x1400;
int loop = 342;
while (loop--) {
*(resultptr++) = savedval ^ *sourceptr;
savedval = *(sourceptr++);
}
*resultptr = savedval;
}
// USING A LOOKUP TABLE, CONVERT THE 6-BIT BYTES INTO DISK BYTES. A VALID
// DISK BYTE IS A BYTE THAT HAS THE HIGH BIT SET, AT LEAST TWO ADJACENT
// BITS SET (EXCLUDING THE HIGH BIT), AND AT MOST ONE PAIR OF CONSECUTIVE
// ZERO BITS. THE CONVERTED BLOCK OF 343 BYTES IS STORED STARTING AT 4K
// INTO THE WORK BUFFER.
{
LPBYTE sourceptr = workbuffer+0x1400;
LPBYTE resultptr = workbuffer+0x1000;
int loop = 343;
while (loop--)
*(resultptr++) = diskbyte[(*(sourceptr++)) >> 2];
}
return workbuffer+0x1000;
}
//===========================================================================
void Decode62 (LPBYTE imageptr) {
// IF WE HAVEN'T ALREADY DONE SO, GENERATE A TABLE FOR CONVERTING
// DISK BYTES BACK INTO 6-BIT BYTES
static BOOL tablegenerated = 0;
static BYTE sixbitbyte[0x80];
if (!tablegenerated) {
ZeroMemory(sixbitbyte,0x80);
int loop = 0;
while (loop < 0x40) {
sixbitbyte[diskbyte[loop]-0x80] = loop << 2;
loop++;
}
tablegenerated = 1;
}
// USING OUR TABLE, CONVERT THE DISK BYTES BACK INTO 6-BIT BYTES
{
LPBYTE sourceptr = workbuffer+0x1000;
LPBYTE resultptr = workbuffer+0x1400;
int loop = 343;
while (loop--)
*(resultptr++) = sixbitbyte[*(sourceptr++) & 0x7F];
}
// EXCLUSIVE-OR THE ENTIRE DATA BLOCK WITH ITSELF OFFSET BY ONE BYTE
// TO UNDO THE EFFECTS OF THE CHECKSUMMING PROCESS
{
BYTE savedval = 0;
LPBYTE sourceptr = workbuffer+0x1400;
LPBYTE resultptr = workbuffer+0x1000;
int loop = 342;
while (loop--) {
*resultptr = savedval ^ *(sourceptr++);
savedval = *(resultptr++);
}
}
// CONVERT THE 342 6-BIT BYTES INTO 256 8-BIT BYTES
{
LPBYTE lowbitsptr = workbuffer+0x1000;
LPBYTE sectorbase = workbuffer+0x1056;
BYTE offset = 0xAC;
while (offset != 0x02) {
if (offset >= 0xAC)
*(imageptr+offset) = (*(sectorbase+offset) & 0xFC)
| (((*lowbitsptr) & 0x80) >> 7)
| (((*lowbitsptr) & 0x40) >> 5);
offset -= 0x56;
*(imageptr+offset) = (*(sectorbase+offset) & 0xFC)
| (((*lowbitsptr) & 0x20) >> 5)
| (((*lowbitsptr) & 0x10) >> 3);
offset -= 0x56;
*(imageptr+offset) = (*(sectorbase+offset) & 0xFC)
| (((*lowbitsptr) & 0x08) >> 3)
| (((*lowbitsptr) & 0x04) >> 1);
offset -= 0x53;
lowbitsptr++;
}
}
}
//===========================================================================
void DenibblizeTrack (LPBYTE trackimage, BOOL dosorder, int nibbles) {
ZeroMemory(workbuffer,0x1000);
// SEARCH THROUGH THE TRACK IMAGE FOR EACH SECTOR. FOR EVERY SECTOR
// WE FIND, COPY THE NIBBLIZED DATA FOR THAT SECTOR INTO THE WORK
// BUFFER AT OFFSET 4K. THEN CALL DECODE62() TO DENIBBLIZE THE DATA
// IN THE BUFFER AND WRITE IT INTO THE FIRST PART OF THE WORK BUFFER
// OFFSET BY THE SECTOR NUMBER.
{
int offset = 0;
int partsleft = 33;
int sector = 0;
while (partsleft--) {
BYTE byteval[3] = {0,0,0};
int bytenum = 0;
int loop = nibbles;
while ((loop--) && (bytenum < 3)) {
if (bytenum)
byteval[bytenum++] = *(trackimage+offset++);
else if (*(trackimage+offset++) == 0xD5)
bytenum = 1;
if (offset >= nibbles)
offset = 0;
}
if ((bytenum == 3) && (byteval[1] = 0xAA)) {
int loop = 0;
int tempoffset = offset;
while (loop < 384) {
*(workbuffer+0x1000+loop++) = *(trackimage+tempoffset++);
if (tempoffset >= nibbles)
tempoffset = 0;
}
if (byteval[2] == 0x96)
sector = ((*(workbuffer+0x1004) & 0x55) << 1)
| (*(workbuffer+0x1005) & 0x55);
else if (byteval[2] == 0xAD) {
Decode62(workbuffer+(sectornumber[dosorder][sector] << 8));
sector = 0;
}
}
}
}
}
//===========================================================================
DWORD NibblizeTrack (LPBYTE trackimagebuffer, BOOL dosorder, int track) {
ZeroMemory(workbuffer+4096,4096);
LPBYTE imageptr = trackimagebuffer;
BYTE sector = 0;
// WRITE GAP ONE, WHICH CONTAINS 48 SELF-SYNC BYTES
int loop;
for (loop = 0; loop < 48; loop++)
*(imageptr++) = 0xFF;
while (sector < 16) {
// WRITE THE ADDRESS FIELD, WHICH CONTAINS:
// - PROLOGUE (D5AA96)
// - VOLUME NUMBER ("4 AND 4" ENCODED)
// - TRACK NUMBER ("4 AND 4" ENCODED)
// - SECTOR NUMBER ("4 AND 4" ENCODED)
// - CHECKSUM ("4 AND 4" ENCODED)
// - EPILOGUE (DEAAEB)
*(imageptr++) = 0xD5;
*(imageptr++) = 0xAA;
*(imageptr++) = 0x96;
#define VOLUME 0xFE
#define CODE44A(a) ((((a) >> 1) & 0x55) | 0xAA)
#define CODE44B(a) (((a) & 0x55) | 0xAA)
*(imageptr++) = CODE44A(VOLUME);
*(imageptr++) = CODE44B(VOLUME);
*(imageptr++) = CODE44A((BYTE)track);
*(imageptr++) = CODE44B((BYTE)track);
*(imageptr++) = CODE44A(sector);
*(imageptr++) = CODE44B(sector);
*(imageptr++) = CODE44A(VOLUME ^ ((BYTE)track) ^ sector);
*(imageptr++) = CODE44B(VOLUME ^ ((BYTE)track) ^ sector);
#undef CODE44A
#undef CODE44B
*(imageptr++) = 0xDE;
*(imageptr++) = 0xAA;
*(imageptr++) = 0xEB;
// WRITE GAP TWO, WHICH CONTAINS SIX SELF-SYNC BYTES
for (loop = 0; loop < 6; loop++)
*(imageptr++) = 0xFF;
// WRITE THE DATA FIELD, WHICH CONTAINS:
// - PROLOGUE (D5AAAD)
// - 343 6-BIT BYTES OF NIBBLIZED DATA, INCLUDING A 6-BIT CHECKSUM
// - EPILOGUE (DEAAEB)
*(imageptr++) = 0xD5;
*(imageptr++) = 0xAA;
*(imageptr++) = 0xAD;
CopyMemory(imageptr,Code62(sectornumber[dosorder][sector]),343);
imageptr += 343;
*(imageptr++) = 0xDE;
*(imageptr++) = 0xAA;
*(imageptr++) = 0xEB;
// WRITE GAP THREE, WHICH CONTAINS 27 SELF-SYNC BYTES
for (loop = 0; loop < 27; loop++)
*(imageptr++) = 0xFF;
sector++;
}
return imageptr-trackimagebuffer;
}
//===========================================================================
void SkewTrack (int track, int nibbles, LPBYTE trackimagebuffer) {
int skewbytes = (track*768) % nibbles;
CopyMemory(workbuffer,trackimagebuffer,nibbles);
CopyMemory(trackimagebuffer,workbuffer+skewbytes,nibbles-skewbytes);
CopyMemory(trackimagebuffer+nibbles-skewbytes,workbuffer,skewbytes);
}
/****************************************************************************
*
* RAW PROGRAM IMAGE (APL) FORMAT IMPLEMENTATION
*
***/
//===========================================================================
BOOL AplBoot (imageinfoptr ptr) {
SetFilePointer(ptr->file,0,NULL,FILE_BEGIN);
WORD address = 0;
WORD length = 0;
DWORD bytesread;
ReadFile(ptr->file,&address,sizeof(WORD),&bytesread,NULL);
ReadFile(ptr->file,&length ,sizeof(WORD),&bytesread,NULL);
if ((((WORD)(address+length)) <= address) ||
(address >= 0xC000) ||
(address+length-1 >= 0xC000))
return 0;
ReadFile(ptr->file,mem+address,length,&bytesread,NULL);
int loop = 192;
while (loop--)
*(memdirty+loop) = 0xFF;
regs.pc = address;
return 1;
}
//===========================================================================
DWORD AplDetect (LPBYTE imageptr, DWORD imagesize) {
DWORD length = *(LPWORD)(imageptr+2);
return (((length+4) == imagesize) ||
((length+4+((256-((length+4) & 255)) & 255)) == imagesize));
}
/****************************************************************************
*
* DOS ORDER (DO) FORMAT IMPLEMENTATION
*
***/
//===========================================================================
DWORD DoDetect (LPBYTE imageptr, DWORD imagesize) {
if (((imagesize < 143105) || (imagesize > 143364)) &&
(imagesize != 143403) && (imagesize != 143488))
return 0;
// CHECK FOR A DOS ORDER IMAGE OF A DOS DISKETTE
{
int loop = 0;
BOOL mismatch = 0;
while ((loop++ < 15) && !mismatch)
if (*(imageptr+0x11002+(loop << 8)) != loop-1)
mismatch = 1;
if (!mismatch)
return 2;
}
// CHECK FOR A DOS ORDER IMAGE OF A PRODOS DISKETTE
{
int loop = 1;
BOOL mismatch = 0;
while ((loop++ < 5) && !mismatch)
if ((*(LPWORD)(imageptr+(loop << 9)+0x100) != ((loop == 5) ? 0 : 6-loop)) ||
(*(LPWORD)(imageptr+(loop << 9)+0x102) != ((loop == 2) ? 0 : 8-loop)))
mismatch = 1;
if (!mismatch)
return 2;
}
return 1;
}
//===========================================================================
void DoRead (imageinfoptr ptr, int track, int quartertrack, LPBYTE trackimagebuffer, int *nibbles) {
SetFilePointer(ptr->file,ptr->offset+(track << 12),NULL,FILE_BEGIN);
ZeroMemory(workbuffer,4096);
DWORD bytesread;
ReadFile(ptr->file,workbuffer,4096,&bytesread,NULL);
*nibbles = NibblizeTrack(trackimagebuffer,1,track);
if (!enhancedisk)
SkewTrack(track,*nibbles,trackimagebuffer);
}
//===========================================================================
void DoWrite (imageinfoptr ptr, int track, int quartertrack, LPBYTE trackimage, int nibbles) {
ZeroMemory(workbuffer,4096);
DenibblizeTrack(trackimage,1,nibbles);
SetFilePointer(ptr->file,ptr->offset+(track << 12),NULL,FILE_BEGIN);
DWORD byteswritten;
WriteFile(ptr->file,workbuffer,4096,&byteswritten,NULL);
}
/****************************************************************************
*
* SIMSYSTEM IIE (IIE) FORMAT IMPLEMENTATION
*
***/
//===========================================================================
void IieConvertSectorOrder (LPBYTE sourceorder) {
int loop = 16;
while (loop--) {
BYTE found = 0xFF;
int loop2 = 16;
while (loop2-- && (found == 0xFF))
if (*(sourceorder+loop2) == loop)
found = loop2;
if (found == 0xFF)
found = 0;
sectornumber[2][loop] = found;
}
}
//===========================================================================
DWORD IieDetect (LPBYTE imageptr, DWORD imagesize) {
if (strncmp((const char *)imageptr,"SIMSYSTEM_IIE",13) ||
(*(imageptr+13) > 3))
return 0;
return 2;
}
//===========================================================================
void IieRead (imageinfoptr ptr, int track, int quartertrack, LPBYTE trackimagebuffer, int *nibbles) {
// IF WE HAVEN'T ALREADY DONE SO, READ THE IMAGE FILE HEADER
if (!ptr->header) {
ptr->header = (LPBYTE)VirtualAlloc(NULL,88,MEM_COMMIT,PAGE_READWRITE);
if (!ptr->header) {
*nibbles = 0;
return;
}
ZeroMemory(ptr->header,88);
DWORD bytesread;
SetFilePointer(ptr->file,0,NULL,FILE_BEGIN);
ReadFile(ptr->file,ptr->header,88,&bytesread,NULL);
}
// IF THIS IMAGE CONTAINS USER DATA, READ THE TRACK AND NIBBLIZE IT
if (*(ptr->header+13) <= 2) {
IieConvertSectorOrder(ptr->header+14);
SetFilePointer(ptr->file,(track << 12)+30,NULL,FILE_BEGIN);
ZeroMemory(workbuffer,4096);
DWORD bytesread;
ReadFile(ptr->file,workbuffer,4096,&bytesread,NULL);
*nibbles = NibblizeTrack(trackimagebuffer,2,track);
}
// OTHERWISE, IF THIS IMAGE CONTAINS NIBBLE INFORMATION, READ IT
// DIRECTLY INTO THE TRACK BUFFER
else {
*nibbles = *(LPWORD)(ptr->header+(track << 1)+14);
DWORD offset = 88;
while (track--)
offset += *(LPWORD)(ptr->header+(track << 1)+14);
SetFilePointer(ptr->file,offset,NULL,FILE_BEGIN);
ZeroMemory(trackimagebuffer,*nibbles);
DWORD bytesread;
ReadFile(ptr->file,trackimagebuffer,*nibbles,&bytesread,NULL);
}
}
//===========================================================================
void IieWrite (imageinfoptr ptr, int track, int quartertrack, LPBYTE trackimage, int nibbles) {
// note: unimplemented
}
/****************************************************************************
*
* NIBBLIZED 6656-NIBBLE (NIB) FORMAT IMPLEMENTATION
*
***/
//===========================================================================
DWORD Nib1Detect (LPBYTE imageptr, DWORD imagesize) {
return (imagesize == 232960) ? 2 : 0;
}
//===========================================================================
void Nib1Read (imageinfoptr ptr, int track, int quartertrack, LPBYTE trackimagebuffer, int *nibbles) {
SetFilePointer(ptr->file,ptr->offset+track*NIBBLES,NULL,FILE_BEGIN);
ReadFile(ptr->file,trackimagebuffer,NIBBLES,(DWORD *)nibbles,NULL);
}
//===========================================================================
void Nib1Write (imageinfoptr ptr, int track, int quartertrack, LPBYTE trackimage, int nibbles) {
SetFilePointer(ptr->file,ptr->offset+track*NIBBLES,NULL,FILE_BEGIN);
DWORD byteswritten;
WriteFile(ptr->file,trackimage,nibbles,&byteswritten,NULL);
}
/****************************************************************************
*
* NIBBLIZED 6384-NIBBLE (NB2) FORMAT IMPLEMENTATION
*
***/
//===========================================================================
DWORD Nib2Detect (LPBYTE imageptr, DWORD imagesize) {
return (imagesize == 223440) ? 2 : 0;
}
//===========================================================================
void Nib2Read (imageinfoptr ptr, int track, int quartertrack, LPBYTE trackimagebuffer, int *nibbles) {
SetFilePointer(ptr->file,ptr->offset+track*6384,NULL,FILE_BEGIN);
ReadFile(ptr->file,trackimagebuffer,6384,(DWORD *)nibbles,NULL);
}
//===========================================================================
void Nib2Write (imageinfoptr ptr, int track, int quartertrack, LPBYTE trackimage, int nibbles) {
SetFilePointer(ptr->file,ptr->offset+track*6384,NULL,FILE_BEGIN);
DWORD byteswritten;
WriteFile(ptr->file,trackimage,nibbles,&byteswritten,NULL);
}
/****************************************************************************
*
* PRODOS ORDER (PO) FORMAT IMPLEMENTATION
*
***/
//===========================================================================
DWORD PoDetect (LPBYTE imageptr, DWORD imagesize) {
if (((imagesize < 143105) || (imagesize > 143364)) &&
(imagesize != 143488))
return 0;
// CHECK FOR A PRODOS ORDER IMAGE OF A DOS DISKETTE
{
int loop = 4;
BOOL mismatch = 0;
while ((loop++ < 13) && !mismatch)
if (*(imageptr+0x11002+(loop << 8)) != 14-loop)
mismatch = 1;
if (!mismatch)
return 2;
}
// CHECK FOR A PRODOS ORDER IMAGE OF A PRODOS DISKETTE
{
int loop = 1;
BOOL mismatch = 0;
while ((loop++ < 5) && !mismatch)
if ((*(LPWORD)(imageptr+(loop << 9) ) != ((loop == 2) ? 0 : loop-1)) ||
(*(LPWORD)(imageptr+(loop << 9)+2) != ((loop == 5) ? 0 : loop+1)))
mismatch = 1;
if (!mismatch)
return 2;
}
return 1;
}
//===========================================================================
void PoRead (imageinfoptr ptr, int track, int quartertrack, LPBYTE trackimagebuffer, int *nibbles) {
SetFilePointer(ptr->file,ptr->offset+(track << 12),NULL,FILE_BEGIN);
ZeroMemory(workbuffer,4096);
DWORD bytesread;
ReadFile(ptr->file,workbuffer,4096,&bytesread,NULL);
*nibbles = NibblizeTrack(trackimagebuffer,0,track);
if (!enhancedisk)
SkewTrack(track,*nibbles,trackimagebuffer);
}
//===========================================================================
void PoWrite (imageinfoptr ptr, int track, int quartertrack, LPBYTE trackimage, int nibbles) {
ZeroMemory(workbuffer,4096);
DenibblizeTrack(trackimage,0,nibbles);
SetFilePointer(ptr->file,ptr->offset+(track << 12),NULL,FILE_BEGIN);
DWORD byteswritten;
WriteFile(ptr->file,workbuffer,4096,&byteswritten,NULL);
}
/****************************************************************************
*
* PRODOS PROGRAM IMAGE (PRG) FORMAT IMPLEMENTATION
*
***/
//===========================================================================
BOOL PrgBoot (imageinfoptr ptr) {
SetFilePointer(ptr->file,5,NULL,FILE_BEGIN);
WORD address = 0;
WORD length = 0;
DWORD bytesread;
ReadFile(ptr->file,&address,sizeof(WORD),&bytesread,NULL);
ReadFile(ptr->file,&length ,sizeof(WORD),&bytesread,NULL);
length <<= 1;
if ((((WORD)(address+length)) <= address) ||
(address >= 0xC000) ||
(address+length-1 >= 0xC000))
return 0;
SetFilePointer(ptr->file,128,NULL,FILE_BEGIN);
ReadFile(ptr->file,mem+address,length,&bytesread,NULL);
int loop = 192;
while (loop--)
*(memdirty+loop) = 0xFF;
regs.pc = address;
return 1;
}
//===========================================================================
DWORD PrgDetect (LPBYTE imageptr, DWORD imagesize) {
return (*(LPDWORD)imageptr == 0x214C470A) ? 2 : 0;
}
//
// ----- ALL GLOBALLY ACCESSIBLE FUNCTIONS ARE BELOW THIS LINE -----
//
//===========================================================================
BOOL ImageBoot (HIMAGE imagehandle) {
imageinfoptr ptr = (imageinfoptr)imagehandle;
BOOL result = 0;
if (imagetype[ptr->format].boot)
result = imagetype[ptr->format].boot(ptr);
if (result)
ptr->writeprotected = 1;
return result;
}
//===========================================================================
void ImageClose (HIMAGE imagehandle) {
imageinfoptr ptr = (imageinfoptr)imagehandle;
if (ptr->file != INVALID_HANDLE_VALUE)
CloseHandle(ptr->file);
for (int track = 0; track < TRACKS; track++)
if (!ptr->validtrack[track]) {
DeleteFile(ptr->filename);
break;
}
if (ptr->header)
VirtualFree(ptr->header,0,MEM_RELEASE);
VirtualFree(ptr,0,MEM_RELEASE);
}
//===========================================================================
void ImageDestroy () {
VirtualFree(workbuffer,0,MEM_RELEASE);
workbuffer = NULL;
}
//===========================================================================
void ImageInitialize () {
workbuffer = (LPBYTE)VirtualAlloc(NULL,0x2000,MEM_COMMIT,PAGE_READWRITE);
}
//===========================================================================
int ImageOpen (LPCTSTR imagefilename,
HIMAGE *hDiskImage_,
BOOL *pWriteProtected_,
BOOL bCreateIfNecessary)
{
if (! (imagefilename && hDiskImage_ && pWriteProtected_ && workbuffer))
return IMAGE_ERROR_BAD_POINTER; // HACK: MAGIC # -1
// TRY TO OPEN THE IMAGE FILE
HANDLE file = INVALID_HANDLE_VALUE;
if (! *pWriteProtected_)
file = CreateFile(imagefilename,
GENERIC_READ | GENERIC_WRITE,
FILE_SHARE_READ | FILE_SHARE_WRITE,
(LPSECURITY_ATTRIBUTES)NULL,
OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL,
NULL);
// File may have read-only attribute set, so try to open as read-only.
if (file == INVALID_HANDLE_VALUE)
{
file = CreateFile(
imagefilename,
GENERIC_READ,
FILE_SHARE_READ,
(LPSECURITY_ATTRIBUTES)NULL,
OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL,
NULL );
if (file != INVALID_HANDLE_VALUE)
*pWriteProtected_ = 1;
}
if ((file == INVALID_HANDLE_VALUE) && bCreateIfNecessary)
file = CreateFile(
imagefilename,
GENERIC_READ | GENERIC_WRITE,
FILE_SHARE_READ | FILE_SHARE_WRITE,
(LPSECURITY_ATTRIBUTES)NULL,
CREATE_NEW,
FILE_ATTRIBUTE_NORMAL,
NULL );
// IF WE AREN'T ABLE TO OPEN THE FILE, RETURN
if (file == INVALID_HANDLE_VALUE)
return IMAGE_ERROR_UNABLE_TO_OPEN; // HACK: MAGIC # 1
// DETERMINE THE FILE'S EXTENSION AND CONVERT IT TO LOWERCASE
LPCTSTR imagefileext = imagefilename;
if (_tcsrchr(imagefileext,TEXT('\\')))
imagefileext = _tcsrchr(imagefileext,TEXT('\\'))+1;
if (_tcsrchr(imagefileext,TEXT('.')))
imagefileext = _tcsrchr(imagefileext,TEXT('.'));
TCHAR ext[_MAX_EXT];
_tcsncpy(ext,imagefileext,_MAX_EXT);
CharLowerBuff(ext,_tcslen(ext));
DWORD size = GetFileSize(file,NULL);
LPBYTE view = NULL;
LPBYTE pImage = NULL;
const DWORD UNKNOWN_FORMAT = 0xFFFFFFFF;
DWORD format = UNKNOWN_FORMAT;
if (size > 0)
{
// MAP THE FILE INTO MEMORY FOR USE BY THE DETECTION FUNCTIONS
HANDLE mapping = CreateFileMapping(
file,
(LPSECURITY_ATTRIBUTES)NULL,
PAGE_READONLY,
0,0,NULL );
view = (LPBYTE)MapViewOfFile(mapping,FILE_MAP_READ,0,0,0);
pImage = view;
if (pImage)
{
// DETERMINE WHETHER THE FILE HAS A 128-BYTE MACBINARY HEADER
if ((size > 128) &&
(!*pImage) &&
(*(pImage+1) < 120) &&
(!*(pImage+*(pImage+1)+2)) &&
(*(pImage+0x7A) == 0x81) &&
(*(pImage+0x7B) == 0x81))
{
pImage += 128;
size -= 128;
}
// CALL THE DETECTION FUNCTIONS IN ORDER, LOOKING FOR A MATCH
DWORD possibleformat = UNKNOWN_FORMAT; // 0xFFFFFFFF;
int loop = 0;
while ((loop < IMAGETYPES) && (format == UNKNOWN_FORMAT)) // 0xFFFFFFFF)) {
{
if (*ext && _tcsstr(imagetype[loop].rejectexts,ext))
++loop;
else
{
DWORD result = imagetype[loop].detect(pImage,size);
if (result == 2)
format = loop;
else if ((result == 1) && (possibleformat == UNKNOWN_FORMAT)) // 0xFFFFFFFF))
possibleformat = loop++;
else
++loop;
}
}
if (format == UNKNOWN_FORMAT) // 0xFFFFFFFF)
format = possibleformat;
// CLOSE THE MEMORY MAPPING
UnmapViewOfFile(view);
}
CloseHandle(mapping);
}
else
{
// WE CREATE ONLY DOS ORDER (DO) OR 6656-NIBBLE (NIB) FORMAT FILES
for (int loop = 1; loop <= 4; loop += 3)
{
if (*ext && _tcsstr(imagetype[loop].createexts,ext))
{
format = loop;
break;
}
}
}
// IF THE FILE DOES MATCH A KNOWN FORMAT...
if (format != UNKNOWN_FORMAT)
{
// CREATE A RECORD FOR THE FILE, AND RETURN AN IMAGE HANDLE
*hDiskImage_ = (HIMAGE)VirtualAlloc(NULL,sizeof(imageinforec),MEM_COMMIT,PAGE_READWRITE);
if (*hDiskImage_)
{
ZeroMemory(*hDiskImage_,sizeof(imageinforec));
_tcsncpy(((imageinfoptr)*hDiskImage_)->filename,imagefilename,MAX_PATH);
((imageinfoptr)*hDiskImage_)->format = format;
((imageinfoptr)*hDiskImage_)->file = file;
((imageinfoptr)*hDiskImage_)->offset = pImage-view;
((imageinfoptr)*hDiskImage_)->writeprotected = *pWriteProtected_;
for (int track = 0; track < TRACKS; track++)
((imageinfoptr)*hDiskImage_)->validtrack[track] = (size > 0);
return IMAGE_ERROR_NONE; // HACK: MAGIC # 0
}
}
CloseHandle(file);
if (!(size > 0))
DeleteFile(imagefilename);
return IMAGE_ERROR_BAD_SIZE; // HACK: MAGIC # 2
}
//===========================================================================
void ImageReadTrack (HIMAGE imagehandle,
int track,
int quartertrack,
LPBYTE trackimagebuffer,
int *nibbles) {
imageinfoptr ptr = (imageinfoptr)imagehandle;
if (imagetype[ptr->format].read && ptr->validtrack[track])
imagetype[ptr->format].read(ptr,track,quartertrack,trackimagebuffer,nibbles);
else
for (*nibbles = 0; *nibbles < NIBBLES; (*nibbles)++)
trackimagebuffer[*nibbles] = (BYTE)(rand() & 0xFF);
}
//===========================================================================
void ImageWriteTrack (HIMAGE imagehandle,
int track,
int quartertrack,
LPBYTE trackimage,
int nibbles) {
imageinfoptr ptr = (imageinfoptr)imagehandle;
if (imagetype[ptr->format].write && !ptr->writeprotected) {
imagetype[ptr->format].write(ptr,track,quartertrack,trackimage,nibbles);
ptr->validtrack[track] = 1;
}
}