dosbox-wii/src/dos/drive_fat.cpp
2021-02-06 16:06:31 +01:00

1436 lines
41 KiB
C++

/*
* Copyright (C) 2002-2019 The DOSBox Team
*
* This program 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.
*
* This program 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 this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include "dosbox.h"
#include "dos_inc.h"
#include "drives.h"
#include "support.h"
#include "cross.h"
#include "bios.h"
#include "bios_disk.h"
#define IMGTYPE_FLOPPY 0
#define IMGTYPE_ISO 1
#define IMGTYPE_HDD 2
#define FAT12 0
#define FAT16 1
#define FAT32 2
class fatFile : public DOS_File {
public:
fatFile(const char* name, Bit32u startCluster, Bit32u fileLen, fatDrive *useDrive);
bool Read(Bit8u * data,Bit16u * size);
bool Write(Bit8u * data,Bit16u * size);
bool Seek(Bit32u * pos,Bit32u type);
bool Close();
Bit16u GetInformation(void);
bool UpdateDateTimeFromHost(void);
public:
Bit32u firstCluster;
Bit32u seekpos;
Bit32u filelength;
Bit32u currentSector;
Bit32u curSectOff;
Bit8u sectorBuffer[512];
/* Record of where in the directory structure this file is located */
Bit32u dirCluster;
Bit32u dirIndex;
bool loadedSector;
fatDrive *myDrive;
private:
enum { NONE,READ,WRITE } last_action;
Bit16u info;
};
/* IN - char * filename: Name in regular filename format, e.g. bob.txt */
/* OUT - char * filearray: Name in DOS directory format, eleven char, e.g. bob txt */
static void convToDirFile(char *filename, char *filearray) {
Bit32u charidx = 0;
Bit32u flen,i;
flen = (Bit32u)strlen(filename);
memset(filearray, 32, 11);
for(i=0;i<flen;i++) {
if(charidx >= 11) break;
if(filename[i] != '.') {
filearray[charidx] = filename[i];
charidx++;
} else {
charidx = 8;
}
}
}
fatFile::fatFile(const char* /*name*/, Bit32u startCluster, Bit32u fileLen, fatDrive *useDrive) {
Bit32u seekto = 0;
firstCluster = startCluster;
myDrive = useDrive;
filelength = fileLen;
open = true;
loadedSector = false;
curSectOff = 0;
seekpos = 0;
memset(&sectorBuffer[0], 0, sizeof(sectorBuffer));
if(filelength > 0) {
Seek(&seekto, DOS_SEEK_SET);
}
}
bool fatFile::Read(Bit8u * data, Bit16u *size) {
if ((this->flags & 0xf) == OPEN_WRITE) { // check if file opened in write-only mode
DOS_SetError(DOSERR_ACCESS_DENIED);
return false;
}
Bit16u sizedec, sizecount;
if(seekpos >= filelength) {
*size = 0;
return true;
}
if (!loadedSector) {
currentSector = myDrive->getAbsoluteSectFromBytePos(firstCluster, seekpos);
if(currentSector == 0) {
/* EOC reached before EOF */
*size = 0;
loadedSector = false;
return true;
}
curSectOff = seekpos % myDrive->getSectorSize();
myDrive->readSector(currentSector, sectorBuffer);
loadedSector = true;
}
sizedec = *size;
sizecount = 0;
while(sizedec != 0) {
if(seekpos >= filelength) {
*size = sizecount;
return true;
}
data[sizecount++] = sectorBuffer[curSectOff++];
seekpos++;
if(curSectOff >= myDrive->getSectorSize()) {
currentSector = myDrive->getAbsoluteSectFromBytePos(firstCluster, seekpos);
if(currentSector == 0) {
/* EOC reached before EOF */
//LOG_MSG("EOC reached before EOF, seekpos %d, filelen %d", seekpos, filelength);
*size = sizecount;
loadedSector = false;
return true;
}
curSectOff = 0;
myDrive->readSector(currentSector, sectorBuffer);
loadedSector = true;
//LOG_MSG("Reading absolute sector at %d for seekpos %d", currentSector, seekpos);
}
--sizedec;
}
*size =sizecount;
return true;
}
bool fatFile::Write(Bit8u * data, Bit16u *size) {
if ((this->flags & 0xf) == OPEN_READ) { // check if file opened in read-only mode
DOS_SetError(DOSERR_ACCESS_DENIED);
return false;
}
direntry tmpentry;
Bit16u sizedec, sizecount;
sizedec = *size;
sizecount = 0;
if(seekpos < filelength && *size == 0) {
/* Truncate file to current position */
myDrive->deleteClustChain(firstCluster, seekpos);
filelength = seekpos;
goto finalizeWrite;
}
if(seekpos > filelength) {
/* Extend file to current position */
Bit32u clustSize = myDrive->getClusterSize();
if(filelength == 0) {
firstCluster = myDrive->getFirstFreeClust();
if(firstCluster == 0) goto finalizeWrite; // out of space
myDrive->allocateCluster(firstCluster, 0);
filelength = clustSize;
}
filelength = ((filelength - 1) / clustSize + 1) * clustSize;
while(filelength < seekpos) {
if(myDrive->appendCluster(firstCluster) == 0) goto finalizeWrite; // out of space
filelength += clustSize;
}
if(filelength > seekpos) filelength = seekpos;
if(*size == 0) goto finalizeWrite;
}
while(sizedec != 0) {
/* Increase filesize if necessary */
if(seekpos >= filelength) {
if(filelength == 0) {
firstCluster = myDrive->getFirstFreeClust();
if(firstCluster == 0) goto finalizeWrite; // out of space
myDrive->allocateCluster(firstCluster, 0);
currentSector = myDrive->getAbsoluteSectFromBytePos(firstCluster, seekpos);
myDrive->readSector(currentSector, sectorBuffer);
loadedSector = true;
}
if (!loadedSector) {
currentSector = myDrive->getAbsoluteSectFromBytePos(firstCluster, seekpos);
if(currentSector == 0) {
/* EOC reached before EOF - try to increase file allocation */
myDrive->appendCluster(firstCluster);
/* Try getting sector again */
currentSector = myDrive->getAbsoluteSectFromBytePos(firstCluster, seekpos);
if(currentSector == 0) {
/* No can do. lets give up and go home. We must be out of room */
goto finalizeWrite;
}
}
curSectOff = seekpos % myDrive->getSectorSize();
myDrive->readSector(currentSector, sectorBuffer);
loadedSector = true;
}
filelength = seekpos+1;
}
sectorBuffer[curSectOff++] = data[sizecount++];
seekpos++;
if(curSectOff >= myDrive->getSectorSize()) {
if(loadedSector) myDrive->writeSector(currentSector, sectorBuffer);
currentSector = myDrive->getAbsoluteSectFromBytePos(firstCluster, seekpos);
if(currentSector == 0) {
/* EOC reached before EOF - try to increase file allocation */
myDrive->appendCluster(firstCluster);
/* Try getting sector again */
currentSector = myDrive->getAbsoluteSectFromBytePos(firstCluster, seekpos);
if(currentSector == 0) {
/* No can do. lets give up and go home. We must be out of room */
loadedSector = false;
goto finalizeWrite;
}
}
curSectOff = 0;
myDrive->readSector(currentSector, sectorBuffer);
loadedSector = true;
}
--sizedec;
}
if(curSectOff>0 && loadedSector) myDrive->writeSector(currentSector, sectorBuffer);
finalizeWrite:
myDrive->directoryBrowse(dirCluster, &tmpentry, dirIndex);
tmpentry.entrysize = filelength;
tmpentry.loFirstClust = (Bit16u)firstCluster;
myDrive->directoryChange(dirCluster, &tmpentry, dirIndex);
*size =sizecount;
return true;
}
bool fatFile::Seek(Bit32u *pos, Bit32u type) {
Bit32s seekto=0;
switch(type) {
case DOS_SEEK_SET:
seekto = (Bit32s)*pos;
break;
case DOS_SEEK_CUR:
/* Is this relative seek signed? */
seekto = (Bit32s)*pos + (Bit32s)seekpos;
break;
case DOS_SEEK_END:
seekto = (Bit32s)filelength + (Bit32s)*pos;
break;
}
// LOG_MSG("Seek to %d with type %d (absolute value %d)", *pos, type, seekto);
if(seekto<0) seekto = 0;
seekpos = (Bit32u)seekto;
currentSector = myDrive->getAbsoluteSectFromBytePos(firstCluster, seekpos);
if (currentSector == 0) {
/* not within file size, thus no sector is available */
loadedSector = false;
} else {
curSectOff = seekpos % myDrive->getSectorSize();
myDrive->readSector(currentSector, sectorBuffer);
loadedSector = true;
}
*pos = seekpos;
return true;
}
bool fatFile::Close() {
/* Flush buffer */
if (loadedSector) myDrive->writeSector(currentSector, sectorBuffer);
return false;
}
Bit16u fatFile::GetInformation(void) {
return 0;
}
bool fatFile::UpdateDateTimeFromHost(void) {
return true;
}
Bit32u fatDrive::getClustFirstSect(Bit32u clustNum) {
return ((clustNum - 2) * bootbuffer.sectorspercluster) + firstDataSector;
}
Bit32u fatDrive::getClusterValue(Bit32u clustNum) {
Bit32u fatoffset=0;
Bit32u fatsectnum;
Bit32u fatentoff;
Bit32u clustValue=0;
switch(fattype) {
case FAT12:
fatoffset = clustNum + (clustNum / 2);
break;
case FAT16:
fatoffset = clustNum * 2;
break;
case FAT32:
fatoffset = clustNum * 4;
break;
}
fatsectnum = bootbuffer.reservedsectors + (fatoffset / bootbuffer.bytespersector) + partSectOff;
fatentoff = fatoffset % bootbuffer.bytespersector;
if(curFatSect != fatsectnum) {
/* Load two sectors at once for FAT12 */
readSector(fatsectnum, &fatSectBuffer[0]);
if (fattype==FAT12)
readSector(fatsectnum+1, &fatSectBuffer[512]);
curFatSect = fatsectnum;
}
switch(fattype) {
case FAT12:
clustValue = *((Bit16u *)&fatSectBuffer[fatentoff]);
if(clustNum & 0x1) {
clustValue >>= 4;
} else {
clustValue &= 0xfff;
}
break;
case FAT16:
clustValue = *((Bit16u *)&fatSectBuffer[fatentoff]);
break;
case FAT32:
clustValue = *((Bit32u *)&fatSectBuffer[fatentoff]);
break;
}
return clustValue;
}
void fatDrive::setClusterValue(Bit32u clustNum, Bit32u clustValue) {
Bit32u fatoffset=0;
Bit32u fatsectnum;
Bit32u fatentoff;
switch(fattype) {
case FAT12:
fatoffset = clustNum + (clustNum / 2);
break;
case FAT16:
fatoffset = clustNum * 2;
break;
case FAT32:
fatoffset = clustNum * 4;
break;
}
fatsectnum = bootbuffer.reservedsectors + (fatoffset / bootbuffer.bytespersector) + partSectOff;
fatentoff = fatoffset % bootbuffer.bytespersector;
if(curFatSect != fatsectnum) {
/* Load two sectors at once for FAT12 */
readSector(fatsectnum, &fatSectBuffer[0]);
if (fattype==FAT12)
readSector(fatsectnum+1, &fatSectBuffer[512]);
curFatSect = fatsectnum;
}
switch(fattype) {
case FAT12: {
Bit16u tmpValue = *((Bit16u *)&fatSectBuffer[fatentoff]);
if(clustNum & 0x1) {
clustValue &= 0xfff;
clustValue <<= 4;
tmpValue &= 0xf;
tmpValue |= (Bit16u)clustValue;
} else {
clustValue &= 0xfff;
tmpValue &= 0xf000;
tmpValue |= (Bit16u)clustValue;
}
*((Bit16u *)&fatSectBuffer[fatentoff]) = tmpValue;
break;
}
case FAT16:
*((Bit16u *)&fatSectBuffer[fatentoff]) = (Bit16u)clustValue;
break;
case FAT32:
*((Bit32u *)&fatSectBuffer[fatentoff]) = clustValue;
break;
}
for(int fc=0;fc<bootbuffer.fatcopies;fc++) {
writeSector(fatsectnum + (fc * bootbuffer.sectorsperfat), &fatSectBuffer[0]);
if (fattype==FAT12) {
if (fatentoff>=511)
writeSector(fatsectnum+1+(fc * bootbuffer.sectorsperfat), &fatSectBuffer[512]);
}
}
}
bool fatDrive::getEntryName(char *fullname, char *entname) {
char dirtoken[DOS_PATHLENGTH];
char * findDir;
char * findFile;
strcpy(dirtoken,fullname);
//LOG_MSG("Testing for filename %s", fullname);
findDir = strtok(dirtoken,"\\");
if (findDir==NULL) {
return true; // root always exists
}
findFile = findDir;
while(findDir != NULL) {
findFile = findDir;
findDir = strtok(NULL,"\\");
}
strcpy(entname, findFile);
return true;
}
bool fatDrive::getFileDirEntry(char const * const filename, direntry * useEntry, Bit32u * dirClust, Bit32u * subEntry) {
size_t len = strlen(filename);
char dirtoken[DOS_PATHLENGTH];
Bit32u currentClust = 0;
direntry foundEntry;
char * findDir;
char * findFile;
strcpy(dirtoken,filename);
findFile=dirtoken;
/* Skip if testing in root directory */
if ((len>0) && (filename[len-1]!='\\')) {
//LOG_MSG("Testing for filename %s", filename);
findDir = strtok(dirtoken,"\\");
findFile = findDir;
while(findDir != NULL) {
imgDTA->SetupSearch(0,DOS_ATTR_DIRECTORY,findDir);
imgDTA->SetDirID(0);
findFile = findDir;
if(!FindNextInternal(currentClust, *imgDTA, &foundEntry)) break;
else {
//Found something. See if it's a directory (findfirst always finds regular files)
char find_name[DOS_NAMELENGTH_ASCII];Bit16u find_date,find_time;Bit32u find_size;Bit8u find_attr;
imgDTA->GetResult(find_name,find_size,find_date,find_time,find_attr);
if(!(find_attr & DOS_ATTR_DIRECTORY)) break;
}
currentClust = foundEntry.loFirstClust;
findDir = strtok(NULL,"\\");
}
} else {
/* Set to root directory */
}
/* Search found directory for our file */
imgDTA->SetupSearch(0,0x7,findFile);
imgDTA->SetDirID(0);
if(!FindNextInternal(currentClust, *imgDTA, &foundEntry)) return false;
memcpy(useEntry, &foundEntry, sizeof(direntry));
*dirClust = (Bit32u)currentClust;
*subEntry = ((Bit32u)imgDTA->GetDirID()-1);
return true;
}
bool fatDrive::getDirClustNum(char *dir, Bit32u *clustNum, bool parDir) {
Bit32u len = (Bit32u)strlen(dir);
char dirtoken[DOS_PATHLENGTH];
Bit32u currentClust = 0;
direntry foundEntry;
char * findDir;
strcpy(dirtoken,dir);
/* Skip if testing for root directory */
if ((len>0) && (dir[len-1]!='\\')) {
//LOG_MSG("Testing for dir %s", dir);
findDir = strtok(dirtoken,"\\");
while(findDir != NULL) {
imgDTA->SetupSearch(0,DOS_ATTR_DIRECTORY,findDir);
imgDTA->SetDirID(0);
findDir = strtok(NULL,"\\");
if(parDir && (findDir == NULL)) break;
char find_name[DOS_NAMELENGTH_ASCII];Bit16u find_date,find_time;Bit32u find_size;Bit8u find_attr;
if(!FindNextInternal(currentClust, *imgDTA, &foundEntry)) {
return false;
} else {
imgDTA->GetResult(find_name,find_size,find_date,find_time,find_attr);
if(!(find_attr &DOS_ATTR_DIRECTORY)) return false;
}
currentClust = foundEntry.loFirstClust;
}
*clustNum = currentClust;
} else {
/* Set to root directory */
*clustNum = 0;
}
return true;
}
Bit8u fatDrive::readSector(Bit32u sectnum, void * data) {
if (absolute) return loadedDisk->Read_AbsoluteSector(sectnum, data);
Bit32u cylindersize = bootbuffer.headcount * bootbuffer.sectorspertrack;
Bit32u cylinder = sectnum / cylindersize;
sectnum %= cylindersize;
Bit32u head = sectnum / bootbuffer.sectorspertrack;
Bit32u sector = sectnum % bootbuffer.sectorspertrack + 1L;
return loadedDisk->Read_Sector(head, cylinder, sector, data);
}
Bit8u fatDrive::writeSector(Bit32u sectnum, void * data) {
if (absolute) return loadedDisk->Write_AbsoluteSector(sectnum, data);
Bit32u cylindersize = bootbuffer.headcount * bootbuffer.sectorspertrack;
Bit32u cylinder = sectnum / cylindersize;
sectnum %= cylindersize;
Bit32u head = sectnum / bootbuffer.sectorspertrack;
Bit32u sector = sectnum % bootbuffer.sectorspertrack + 1L;
return loadedDisk->Write_Sector(head, cylinder, sector, data);
}
Bit32u fatDrive::getSectorSize(void) {
return bootbuffer.bytespersector;
}
Bit32u fatDrive::getClusterSize(void) {
return bootbuffer.sectorspercluster * bootbuffer.bytespersector;
}
Bit32u fatDrive::getAbsoluteSectFromBytePos(Bit32u startClustNum, Bit32u bytePos) {
return getAbsoluteSectFromChain(startClustNum, bytePos / bootbuffer.bytespersector);
}
Bit32u fatDrive::getAbsoluteSectFromChain(Bit32u startClustNum, Bit32u logicalSector) {
Bit32s skipClust = logicalSector / bootbuffer.sectorspercluster;
Bit32u sectClust = logicalSector % bootbuffer.sectorspercluster;
Bit32u currentClust = startClustNum;
Bit32u testvalue;
while(skipClust!=0) {
bool isEOF = false;
testvalue = getClusterValue(currentClust);
switch(fattype) {
case FAT12:
if(testvalue >= 0xff8) isEOF = true;
break;
case FAT16:
if(testvalue >= 0xfff8) isEOF = true;
break;
case FAT32:
if(testvalue >= 0xfffffff8) isEOF = true;
break;
}
if((isEOF) && (skipClust>=1)) {
//LOG_MSG("End of cluster chain reached before end of logical sector seek!");
if (skipClust == 1 && fattype == FAT12) {
//break;
LOG(LOG_DOSMISC,LOG_ERROR)("End of cluster chain reached, but maybe good afterall ?");
}
return 0;
}
currentClust = testvalue;
--skipClust;
}
return (getClustFirstSect(currentClust) + sectClust);
}
void fatDrive::deleteClustChain(Bit32u startCluster, Bit32u bytePos) {
Bit32u clustSize = getClusterSize();
Bit32u endClust = (bytePos + clustSize - 1) / clustSize;
Bit32u countClust = 1;
Bit32u testvalue;
Bit32u currentClust = startCluster;
bool isEOF = false;
while(!isEOF) {
testvalue = getClusterValue(currentClust);
if(testvalue == 0) {
/* What the crap? Cluster is already empty - BAIL! */
break;
}
switch(fattype) {
case FAT12:
if(testvalue >= 0xff8) isEOF = true;
break;
case FAT16:
if(testvalue >= 0xfff8) isEOF = true;
break;
case FAT32:
if(testvalue >= 0xfffffff8) isEOF = true;
break;
}
if(countClust == endClust && !isEOF) {
/* Mark cluster as end */
switch(fattype) {
case FAT12:
setClusterValue(currentClust, 0xfff);
break;
case FAT16:
setClusterValue(currentClust, 0xffff);
break;
case FAT32:
setClusterValue(currentClust, 0xffffffff);
break;
}
} else if(countClust > endClust) {
/* Mark cluster as empty */
setClusterValue(currentClust, 0);
}
if(isEOF) break;
currentClust = testvalue;
countClust++;
}
}
Bit32u fatDrive::appendCluster(Bit32u startCluster) {
Bit32u testvalue;
Bit32u currentClust = startCluster;
bool isEOF = false;
while(!isEOF) {
testvalue = getClusterValue(currentClust);
switch(fattype) {
case FAT12:
if(testvalue >= 0xff8) isEOF = true;
break;
case FAT16:
if(testvalue >= 0xfff8) isEOF = true;
break;
case FAT32:
if(testvalue >= 0xfffffff8) isEOF = true;
break;
}
if(isEOF) break;
currentClust = testvalue;
}
Bit32u newClust = getFirstFreeClust();
/* Drive is full */
if(newClust == 0) return 0;
if(!allocateCluster(newClust, currentClust)) return 0;
zeroOutCluster(newClust);
return newClust;
}
bool fatDrive::allocateCluster(Bit32u useCluster, Bit32u prevCluster) {
/* Can't allocate cluster #0 */
if(useCluster == 0) return false;
if(prevCluster != 0) {
/* Refuse to allocate cluster if previous cluster value is zero (unallocated) */
if(!getClusterValue(prevCluster)) return false;
/* Point cluster to new cluster in chain */
setClusterValue(prevCluster, useCluster);
//LOG_MSG("Chaining cluser %d to %d", prevCluster, useCluster);
}
switch(fattype) {
case FAT12:
setClusterValue(useCluster, 0xfff);
break;
case FAT16:
setClusterValue(useCluster, 0xffff);
break;
case FAT32:
setClusterValue(useCluster, 0xffffffff);
break;
}
return true;
}
fatDrive::fatDrive(const char *sysFilename, Bit32u bytesector, Bit32u cylsector, Bit32u headscyl, Bit32u cylinders, Bit32u startSector) {
created_successfully = true;
FILE *diskfile;
Bit32u filesize;
bool is_hdd;
struct partTable mbrData;
if(imgDTASeg == 0) {
imgDTASeg = DOS_GetMemory(2);
imgDTAPtr = RealMake(imgDTASeg, 0);
imgDTA = new DOS_DTA(imgDTAPtr);
}
diskfile = fopen_wrap(sysFilename, "rb+");
if(!diskfile) {created_successfully = false;return;}
fseek(diskfile, 0L, SEEK_END);
filesize = (Bit32u)ftell(diskfile) / 1024L;
is_hdd = (filesize > 2880);
/* Load disk image */
loadedDisk = new imageDisk(diskfile, sysFilename, filesize, is_hdd);
if(!loadedDisk) {
created_successfully = false;
return;
}
if(is_hdd) {
/* Set user specified harddrive parameters */
loadedDisk->Set_Geometry(headscyl, cylinders,cylsector, bytesector);
loadedDisk->Read_Sector(0,0,1,&mbrData);
if(mbrData.magic1!= 0x55 || mbrData.magic2!= 0xaa) LOG_MSG("Possibly invalid partition table in disk image.");
startSector = 63;
int m;
for(m=0;m<4;m++) {
/* Pick the first available partition */
if(mbrData.pentry[m].partSize != 0x00) {
LOG_MSG("Using partition %d on drive; skipping %d sectors", m, mbrData.pentry[m].absSectStart);
startSector = mbrData.pentry[m].absSectStart;
break;
}
}
if(m==4) LOG_MSG("No good partition found in image.");
partSectOff = startSector;
} else {
/* Get floppy disk parameters based on image size */
loadedDisk->Get_Geometry(&headscyl, &cylinders, &cylsector, &bytesector);
/* Floppy disks don't have partitions */
partSectOff = 0;
}
if (bytesector != 512) {
/* Non-standard sector sizes not implemented */
created_successfully = false;
return;
}
loadedDisk->Read_AbsoluteSector(0+partSectOff,&bootbuffer);
if (!is_hdd) {
/* Identify floppy format */
if ((bootbuffer.nearjmp[0] == 0x69 || bootbuffer.nearjmp[0] == 0xe9 ||
(bootbuffer.nearjmp[0] == 0xeb && bootbuffer.nearjmp[2] == 0x90)) &&
(bootbuffer.mediadescriptor & 0xf0) == 0xf0) {
/* DOS 2.x or later format, BPB assumed valid */
if ((bootbuffer.mediadescriptor != 0xf0 && !(bootbuffer.mediadescriptor & 0x1)) &&
(bootbuffer.oemname[5] != '3' || bootbuffer.oemname[6] != '.' || bootbuffer.oemname[7] < '2')) {
/* Fix pre-DOS 3.2 single-sided floppy */
bootbuffer.sectorspercluster = 1;
}
} else {
/* Read media descriptor in FAT */
Bit8u sectorBuffer[512];
loadedDisk->Read_AbsoluteSector(1,&sectorBuffer);
Bit8u mdesc = sectorBuffer[0];
if (mdesc >= 0xf8) {
/* DOS 1.x format, create BPB for 160kB floppy */
bootbuffer.bytespersector = 512;
bootbuffer.sectorspercluster = 1;
bootbuffer.reservedsectors = 1;
bootbuffer.fatcopies = 2;
bootbuffer.rootdirentries = 64;
bootbuffer.totalsectorcount = 320;
bootbuffer.mediadescriptor = mdesc;
bootbuffer.sectorsperfat = 1;
bootbuffer.sectorspertrack = 8;
bootbuffer.headcount = 1;
bootbuffer.magic1 = 0x55; // to silence warning
bootbuffer.magic2 = 0xaa;
if (!(mdesc & 0x2)) {
/* Adjust for 9 sectors per track */
bootbuffer.totalsectorcount = 360;
bootbuffer.sectorsperfat = 2;
bootbuffer.sectorspertrack = 9;
}
if (mdesc & 0x1) {
/* Adjust for 2 sides */
bootbuffer.sectorspercluster = 2;
bootbuffer.rootdirentries = 112;
bootbuffer.totalsectorcount *= 2;
bootbuffer.headcount = 2;
}
} else {
/* Unknown format */
created_successfully = false;
return;
}
}
}
if ((bootbuffer.magic1 != 0x55) || (bootbuffer.magic2 != 0xaa)) {
/* Not a FAT filesystem */
LOG_MSG("Loaded image has no valid magicnumbers at the end!");
}
/* Sanity checks */
if ((bootbuffer.sectorsperfat == 0) || // FAT32 not implemented yet
(bootbuffer.bytespersector != 512) || // non-standard sector sizes not implemented
(bootbuffer.sectorspercluster == 0) ||
(bootbuffer.rootdirentries == 0) ||
(bootbuffer.fatcopies == 0) ||
(bootbuffer.headcount == 0) ||
(bootbuffer.headcount > headscyl) ||
(bootbuffer.sectorspertrack == 0) ||
(bootbuffer.sectorspertrack > cylsector)) {
created_successfully = false;
return;
}
/* Filesystem must be contiguous to use absolute sectors, otherwise CHS will be used */
absolute = ((bootbuffer.headcount == headscyl) && (bootbuffer.sectorspertrack == cylsector));
/* Determine FAT format, 12, 16 or 32 */
/* Get size of root dir in sectors */
Bit32u RootDirSectors = ((bootbuffer.rootdirentries * 32) + (bootbuffer.bytespersector - 1)) / bootbuffer.bytespersector;
Bit32u DataSectors;
if(bootbuffer.totalsectorcount != 0) {
DataSectors = bootbuffer.totalsectorcount - (bootbuffer.reservedsectors + (bootbuffer.fatcopies * bootbuffer.sectorsperfat) + RootDirSectors);
} else {
DataSectors = bootbuffer.totalsecdword - (bootbuffer.reservedsectors + (bootbuffer.fatcopies * bootbuffer.sectorsperfat) + RootDirSectors);
}
CountOfClusters = DataSectors / bootbuffer.sectorspercluster;
firstDataSector = (bootbuffer.reservedsectors + (bootbuffer.fatcopies * bootbuffer.sectorsperfat) + RootDirSectors) + partSectOff;
firstRootDirSect = bootbuffer.reservedsectors + (bootbuffer.fatcopies * bootbuffer.sectorsperfat) + partSectOff;
if(CountOfClusters < 4085) {
/* Volume is FAT12 */
LOG_MSG("Mounted FAT volume is FAT12 with %d clusters", CountOfClusters);
fattype = FAT12;
} else if (CountOfClusters < 65525) {
LOG_MSG("Mounted FAT volume is FAT16 with %d clusters", CountOfClusters);
fattype = FAT16;
} else {
LOG_MSG("Mounted FAT volume is FAT32 with %d clusters", CountOfClusters);
fattype = FAT32;
}
/* There is no cluster 0, this means we are in the root directory */
cwdDirCluster = 0;
memset(fatSectBuffer,0,1024);
curFatSect = 0xffffffff;
strcpy(info, "fatDrive ");
strcat(info, sysFilename);
}
bool fatDrive::AllocationInfo(Bit16u *_bytes_sector, Bit8u *_sectors_cluster, Bit16u *_total_clusters, Bit16u *_free_clusters) {
Bit32u hs, cy, sect,sectsize;
Bit32u countFree = 0;
Bit32u i;
loadedDisk->Get_Geometry(&hs, &cy, &sect, &sectsize);
*_bytes_sector = (Bit16u)sectsize;
*_sectors_cluster = bootbuffer.sectorspercluster;
if (CountOfClusters<65536) *_total_clusters = (Bit16u)CountOfClusters;
else {
// maybe some special handling needed for fat32
*_total_clusters = 65535;
}
for(i=0;i<CountOfClusters;i++) if(!getClusterValue(i+2)) countFree++;
if (countFree<65536) *_free_clusters = (Bit16u)countFree;
else {
// maybe some special handling needed for fat32
*_free_clusters = 65535;
}
return true;
}
Bit32u fatDrive::getFirstFreeClust(void) {
Bit32u i;
for(i=0;i<CountOfClusters;i++) {
if(!getClusterValue(i+2)) return (i+2);
}
/* No free cluster found */
return 0;
}
bool fatDrive::isRemote(void) { return false; }
bool fatDrive::isRemovable(void) { return false; }
Bits fatDrive::UnMount(void) {
delete this;
return 0;
}
Bit8u fatDrive::GetMediaByte(void) { return loadedDisk->GetBiosType(); }
bool fatDrive::FileCreate(DOS_File **file, char *name, Bit16u attributes) {
direntry fileEntry;
Bit32u dirClust, subEntry;
char dirName[DOS_NAMELENGTH_ASCII];
char pathName[11];
Bit16u save_errorcode=dos.errorcode;
/* Check if file already exists */
if(getFileDirEntry(name, &fileEntry, &dirClust, &subEntry)) {
/* Truncate file */
fileEntry.entrysize=0;
directoryChange(dirClust, &fileEntry, subEntry);
if(fileEntry.loFirstClust != 0) deleteClustChain(fileEntry.loFirstClust, 0);
} else {
/* Can we even get the name of the file itself? */
if(!getEntryName(name, &dirName[0])) return false;
convToDirFile(&dirName[0], &pathName[0]);
/* Can we find the base directory? */
if(!getDirClustNum(name, &dirClust, true)) return false;
memset(&fileEntry, 0, sizeof(direntry));
memcpy(&fileEntry.entryname, &pathName[0], 11);
fileEntry.attrib = (Bit8u)(attributes & 0xff);
addDirectoryEntry(dirClust, fileEntry);
/* Check if file exists now */
if(!getFileDirEntry(name, &fileEntry, &dirClust, &subEntry)) return false;
}
/* Empty file created, now lets open it */
/* TODO: check for read-only flag and requested write access */
*file = new fatFile(name, fileEntry.loFirstClust, fileEntry.entrysize, this);
(*file)->flags=OPEN_READWRITE;
((fatFile *)(*file))->dirCluster = dirClust;
((fatFile *)(*file))->dirIndex = subEntry;
/* Maybe modTime and date should be used ? (crt matches findnext) */
((fatFile *)(*file))->time = fileEntry.crtTime;
((fatFile *)(*file))->date = fileEntry.crtDate;
dos.errorcode=save_errorcode;
return true;
}
bool fatDrive::FileExists(const char *name) {
direntry fileEntry;
Bit32u dummy1, dummy2;
if(!getFileDirEntry(name, &fileEntry, &dummy1, &dummy2)) return false;
return true;
}
bool fatDrive::FileOpen(DOS_File **file, char *name, Bit32u flags) {
direntry fileEntry;
Bit32u dirClust, subEntry;
if(!getFileDirEntry(name, &fileEntry, &dirClust, &subEntry)) return false;
/* TODO: check for read-only flag and requested write access */
*file = new fatFile(name, fileEntry.loFirstClust, fileEntry.entrysize, this);
(*file)->flags = flags;
((fatFile *)(*file))->dirCluster = dirClust;
((fatFile *)(*file))->dirIndex = subEntry;
/* Maybe modTime and date should be used ? (crt matches findnext) */
((fatFile *)(*file))->time = fileEntry.crtTime;
((fatFile *)(*file))->date = fileEntry.crtDate;
return true;
}
bool fatDrive::FileStat(const char * /*name*/, FileStat_Block *const /*stat_block*/) {
/* TODO: Stub */
return false;
}
bool fatDrive::FileUnlink(char * name) {
direntry fileEntry;
Bit32u dirClust, subEntry;
if(!getFileDirEntry(name, &fileEntry, &dirClust, &subEntry)) return false;
fileEntry.entryname[0] = 0xe5;
directoryChange(dirClust, &fileEntry, subEntry);
if(fileEntry.loFirstClust != 0) deleteClustChain(fileEntry.loFirstClust, 0);
return true;
}
bool fatDrive::FindFirst(char *_dir, DOS_DTA &dta,bool /*fcb_findfirst*/) {
direntry dummyClust;
#if 0
Bit8u attr;char pattern[DOS_NAMELENGTH_ASCII];
dta.GetSearchParams(attr,pattern);
if(attr==DOS_ATTR_VOLUME) {
if (strcmp(GetLabel(), "") == 0 ) {
DOS_SetError(DOSERR_NO_MORE_FILES);
return false;
}
dta.SetResult(GetLabel(),0,0,0,DOS_ATTR_VOLUME);
return true;
}
if(attr & DOS_ATTR_VOLUME) //check for root dir or fcb_findfirst
LOG(LOG_DOSMISC,LOG_WARN)("findfirst for volumelabel used on fatDrive. Unhandled!!!!!");
#endif
if(!getDirClustNum(_dir, &cwdDirCluster, false)) {
DOS_SetError(DOSERR_PATH_NOT_FOUND);
return false;
}
dta.SetDirID(0);
dta.SetDirIDCluster((Bit16u)(cwdDirCluster&0xffff));
return FindNextInternal(cwdDirCluster, dta, &dummyClust);
}
char* removeTrailingSpaces(char* str) {
char* end = str + strlen(str);
while((*--end == ' ') && (end > str)) {};
*++end = '\0';
return str;
}
char* removeLeadingSpaces(char* str) {
size_t len = strlen(str);
size_t pos = strspn(str," ");
memmove(str,str + pos,len - pos + 1);
return str;
}
char* trimString(char* str) {
return removeTrailingSpaces(removeLeadingSpaces(str));
}
bool fatDrive::FindNextInternal(Bit32u dirClustNumber, DOS_DTA &dta, direntry *foundEntry) {
direntry sectbuf[16]; /* 16 directory entries per sector */
Bit32u logentsector; /* Logical entry sector */
Bit32u entryoffset; /* Index offset within sector */
Bit32u tmpsector;
Bit8u attrs;
Bit16u dirPos;
char srch_pattern[DOS_NAMELENGTH_ASCII];
char find_name[DOS_NAMELENGTH_ASCII];
char extension[4];
dta.GetSearchParams(attrs, srch_pattern);
dirPos = dta.GetDirID();
nextfile:
logentsector = dirPos / 16;
entryoffset = dirPos % 16;
if(dirClustNumber==0) {
if(dirPos >= bootbuffer.rootdirentries) {
DOS_SetError(DOSERR_NO_MORE_FILES);
return false;
}
readSector(firstRootDirSect+logentsector,sectbuf);
} else {
tmpsector = getAbsoluteSectFromChain(dirClustNumber, logentsector);
/* A zero sector number can't happen */
if(tmpsector == 0) {
DOS_SetError(DOSERR_NO_MORE_FILES);
return false;
}
readSector(tmpsector,sectbuf);
}
dirPos++;
dta.SetDirID(dirPos);
/* Deleted file entry */
if (sectbuf[entryoffset].entryname[0] == 0xe5) goto nextfile;
/* End of directory list */
if (sectbuf[entryoffset].entryname[0] == 0x00) {
DOS_SetError(DOSERR_NO_MORE_FILES);
return false;
}
memset(find_name,0,DOS_NAMELENGTH_ASCII);
memset(extension,0,4);
memcpy(find_name,&sectbuf[entryoffset].entryname[0],8);
memcpy(extension,&sectbuf[entryoffset].entryname[8],3);
trimString(&find_name[0]);
trimString(&extension[0]);
//if(!(sectbuf[entryoffset].attrib & DOS_ATTR_DIRECTORY))
if (extension[0]!=0) {
strcat(find_name, ".");
strcat(find_name, extension);
}
/* Compare attributes to search attributes */
//TODO What about attrs = DOS_ATTR_VOLUME|DOS_ATTR_DIRECTORY ?
if (attrs == DOS_ATTR_VOLUME) {
if (!(sectbuf[entryoffset].attrib & DOS_ATTR_VOLUME)) goto nextfile;
dirCache.SetLabel(find_name, false, true);
} else {
if (~attrs & sectbuf[entryoffset].attrib & (DOS_ATTR_DIRECTORY | DOS_ATTR_VOLUME | DOS_ATTR_SYSTEM | DOS_ATTR_HIDDEN) ) goto nextfile;
}
/* Compare name to search pattern */
if(!WildFileCmp(find_name,srch_pattern)) goto nextfile;
//dta.SetResult(find_name, sectbuf[entryoffset].entrysize, sectbuf[entryoffset].crtDate, sectbuf[entryoffset].crtTime, sectbuf[entryoffset].attrib);
dta.SetResult(find_name, sectbuf[entryoffset].entrysize, sectbuf[entryoffset].modDate, sectbuf[entryoffset].modTime, sectbuf[entryoffset].attrib);
memcpy(foundEntry, &sectbuf[entryoffset], sizeof(direntry));
return true;
}
bool fatDrive::FindNext(DOS_DTA &dta) {
direntry dummyClust;
return FindNextInternal(dta.GetDirIDCluster(), dta, &dummyClust);
}
bool fatDrive::GetFileAttr(char *name, Bit16u *attr) {
direntry fileEntry;
Bit32u dirClust, subEntry;
if(!getFileDirEntry(name, &fileEntry, &dirClust, &subEntry)) {
char dirName[DOS_NAMELENGTH_ASCII];
char pathName[11];
/* Can we even get the name of the directory itself? */
if(!getEntryName(name, &dirName[0])) return false;
convToDirFile(&dirName[0], &pathName[0]);
/* Get parent directory starting cluster */
if(!getDirClustNum(name, &dirClust, true)) return false;
/* Find directory entry in parent directory */
Bit32s fileidx = 2;
if (dirClust==0) fileidx = 0; // root directory
Bit32s last_idx=0;
while(directoryBrowse(dirClust, &fileEntry, fileidx, last_idx)) {
if(memcmp(&fileEntry.entryname, &pathName[0], 11) == 0) {
*attr=fileEntry.attrib;
return true;
}
last_idx=fileidx;
fileidx++;
}
return false;
} else *attr=fileEntry.attrib;
return true;
}
bool fatDrive::directoryBrowse(Bit32u dirClustNumber, direntry *useEntry, Bit32s entNum, Bit32s start/*=0*/) {
direntry sectbuf[16]; /* 16 directory entries per sector */
Bit32u logentsector; /* Logical entry sector */
Bit32u entryoffset = 0; /* Index offset within sector */
Bit32u tmpsector;
if ((start<0) || (start>65535)) return false;
Bit16u dirPos = (Bit16u)start;
if (entNum<start) return false;
entNum-=start;
while(entNum>=0) {
logentsector = dirPos / 16;
entryoffset = dirPos % 16;
if(dirClustNumber==0) {
if(dirPos >= bootbuffer.rootdirentries) return false;
tmpsector = firstRootDirSect+logentsector;
readSector(tmpsector,sectbuf);
} else {
tmpsector = getAbsoluteSectFromChain(dirClustNumber, logentsector);
/* A zero sector number can't happen */
if(tmpsector == 0) return false;
readSector(tmpsector,sectbuf);
}
dirPos++;
/* End of directory list */
if (sectbuf[entryoffset].entryname[0] == 0x00) return false;
--entNum;
}
memcpy(useEntry, &sectbuf[entryoffset],sizeof(direntry));
return true;
}
bool fatDrive::directoryChange(Bit32u dirClustNumber, direntry *useEntry, Bit32s entNum) {
direntry sectbuf[16]; /* 16 directory entries per sector */
Bit32u logentsector; /* Logical entry sector */
Bit32u entryoffset = 0; /* Index offset within sector */
Bit32u tmpsector = 0;
Bit16u dirPos = 0;
while(entNum>=0) {
logentsector = dirPos / 16;
entryoffset = dirPos % 16;
if(dirClustNumber==0) {
if(dirPos >= bootbuffer.rootdirentries) return false;
tmpsector = firstRootDirSect+logentsector;
readSector(tmpsector,sectbuf);
} else {
tmpsector = getAbsoluteSectFromChain(dirClustNumber, logentsector);
/* A zero sector number can't happen */
if(tmpsector == 0) return false;
readSector(tmpsector,sectbuf);
}
dirPos++;
/* End of directory list */
if (sectbuf[entryoffset].entryname[0] == 0x00) return false;
--entNum;
}
if(tmpsector != 0) {
memcpy(&sectbuf[entryoffset], useEntry, sizeof(direntry));
writeSector(tmpsector, sectbuf);
return true;
} else {
return false;
}
}
bool fatDrive::addDirectoryEntry(Bit32u dirClustNumber, direntry useEntry) {
direntry sectbuf[16]; /* 16 directory entries per sector */
Bit32u logentsector; /* Logical entry sector */
Bit32u entryoffset; /* Index offset within sector */
Bit32u tmpsector;
Bit16u dirPos = 0;
for(;;) {
logentsector = dirPos / 16;
entryoffset = dirPos % 16;
if(dirClustNumber==0) {
if(dirPos >= bootbuffer.rootdirentries) return false;
tmpsector = firstRootDirSect+logentsector;
readSector(tmpsector,sectbuf);
} else {
tmpsector = getAbsoluteSectFromChain(dirClustNumber, logentsector);
/* A zero sector number can't happen - we need to allocate more room for this directory*/
if(tmpsector == 0) {
Bit32u newClust;
newClust = appendCluster(dirClustNumber);
if(newClust == 0) return false;
/* Try again to get tmpsector */
tmpsector = getAbsoluteSectFromChain(dirClustNumber, logentsector);
if(tmpsector == 0) return false; /* Give up if still can't get more room for directory */
}
readSector(tmpsector,sectbuf);
}
dirPos++;
/* Deleted file entry or end of directory list */
if ((sectbuf[entryoffset].entryname[0] == 0xe5) || (sectbuf[entryoffset].entryname[0] == 0x00)) {
sectbuf[entryoffset] = useEntry;
writeSector(tmpsector,sectbuf);
break;
}
}
return true;
}
void fatDrive::zeroOutCluster(Bit32u clustNumber) {
Bit8u secBuffer[512];
memset(&secBuffer[0], 0, 512);
int i;
for(i=0;i<bootbuffer.sectorspercluster;i++) {
writeSector(getAbsoluteSectFromChain(clustNumber,i), &secBuffer[0]);
}
}
bool fatDrive::MakeDir(char *dir) {
Bit32u dummyClust, dirClust;
direntry tmpentry;
char dirName[DOS_NAMELENGTH_ASCII];
char pathName[11];
/* Can we even get the name of the directory itself? */
if(!getEntryName(dir, &dirName[0])) return false;
convToDirFile(&dirName[0], &pathName[0]);
/* Fail to make directory if already exists */
if(getDirClustNum(dir, &dummyClust, false)) return false;
dummyClust = getFirstFreeClust();
/* No more space */
if(dummyClust == 0) return false;
if(!allocateCluster(dummyClust, 0)) return false;
zeroOutCluster(dummyClust);
/* Can we find the base directory? */
if(!getDirClustNum(dir, &dirClust, true)) return false;
/* Add the new directory to the base directory */
memset(&tmpentry,0, sizeof(direntry));
memcpy(&tmpentry.entryname, &pathName[0], 11);
tmpentry.loFirstClust = (Bit16u)(dummyClust & 0xffff);
tmpentry.hiFirstClust = (Bit16u)(dummyClust >> 16);
tmpentry.attrib = DOS_ATTR_DIRECTORY;
addDirectoryEntry(dirClust, tmpentry);
/* Add the [.] and [..] entries to our new directory*/
/* [.] entry */
memset(&tmpentry,0, sizeof(direntry));
memcpy(&tmpentry.entryname, ". ", 11);
tmpentry.loFirstClust = (Bit16u)(dummyClust & 0xffff);
tmpentry.hiFirstClust = (Bit16u)(dummyClust >> 16);
tmpentry.attrib = DOS_ATTR_DIRECTORY;
addDirectoryEntry(dummyClust, tmpentry);
/* [..] entry */
memset(&tmpentry,0, sizeof(direntry));
memcpy(&tmpentry.entryname, ".. ", 11);
tmpentry.loFirstClust = (Bit16u)(dirClust & 0xffff);
tmpentry.hiFirstClust = (Bit16u)(dirClust >> 16);
tmpentry.attrib = DOS_ATTR_DIRECTORY;
addDirectoryEntry(dummyClust, tmpentry);
return true;
}
bool fatDrive::RemoveDir(char *dir) {
Bit32u dummyClust, dirClust;
direntry tmpentry;
char dirName[DOS_NAMELENGTH_ASCII];
char pathName[11];
/* Can we even get the name of the directory itself? */
if(!getEntryName(dir, &dirName[0])) return false;
convToDirFile(&dirName[0], &pathName[0]);
/* Get directory starting cluster */
if(!getDirClustNum(dir, &dummyClust, false)) return false;
/* Can't remove root directory */
if(dummyClust == 0) return false;
/* Get parent directory starting cluster */
if(!getDirClustNum(dir, &dirClust, true)) return false;
/* Check to make sure directory is empty */
Bit32u filecount = 0;
/* Set to 2 to skip first 2 entries, [.] and [..] */
Bit32s fileidx = 2;
while(directoryBrowse(dummyClust, &tmpentry, fileidx)) {
/* Check for non-deleted files */
if(tmpentry.entryname[0] != 0xe5) filecount++;
fileidx++;
}
/* Return if directory is not empty */
if(filecount > 0) return false;
/* Find directory entry in parent directory */
if (dirClust==0) fileidx = 0; // root directory
else fileidx = 2;
bool found = false;
while(directoryBrowse(dirClust, &tmpentry, fileidx)) {
if(memcmp(&tmpentry.entryname, &pathName[0], 11) == 0) {
found = true;
tmpentry.entryname[0] = 0xe5;
directoryChange(dirClust, &tmpentry, fileidx);
deleteClustChain(dummyClust, 0);
break;
}
fileidx++;
}
if(!found) return false;
return true;
}
bool fatDrive::Rename(char * oldname, char * newname) {
direntry fileEntry1;
Bit32u dirClust1, subEntry1;
if(!getFileDirEntry(oldname, &fileEntry1, &dirClust1, &subEntry1)) return false;
/* File to be renamed really exists */
direntry fileEntry2;
Bit32u dirClust2, subEntry2;
/* Check if file already exists */
if(!getFileDirEntry(newname, &fileEntry2, &dirClust2, &subEntry2)) {
/* Target doesn't exist, can rename */
char dirName2[DOS_NAMELENGTH_ASCII];
char pathName2[11];
/* Can we even get the name of the file itself? */
if(!getEntryName(newname, &dirName2[0])) return false;
convToDirFile(&dirName2[0], &pathName2[0]);
/* Can we find the base directory? */
if(!getDirClustNum(newname, &dirClust2, true)) return false;
memcpy(&fileEntry2, &fileEntry1, sizeof(direntry));
memcpy(&fileEntry2.entryname, &pathName2[0], 11);
addDirectoryEntry(dirClust2, fileEntry2);
/* Check if file exists now */
if(!getFileDirEntry(newname, &fileEntry2, &dirClust2, &subEntry2)) return false;
/* Remove old entry */
fileEntry1.entryname[0] = 0xe5;
directoryChange(dirClust1, &fileEntry1, subEntry1);
return true;
}
/* Target already exists, fail */
return false;
}
bool fatDrive::TestDir(char *dir) {
Bit32u dummyClust;
return getDirClustNum(dir, &dummyClust, false);
}