windows-nt/Source/XPSP1/NT/com/ole32/stg/utils/chkdsk/chkdsk.cxx
2020-09-26 16:20:57 +08:00

375 lines
9.2 KiB
C++

//-----------------------------------------------------------------------
//
// File: chkdsk.cxx
//
// Contents: Sanity checking and recovery mechanism for multistream files
//
// Argument:
//
// History: 9-July-92 t-chrisy Created.
//------------------------------------------------------------------------
#include "chkdsk.hxx"
// Global variables, declared as so for convenience.
CMSFHeader *pheader;
CFat *pFat;
CFat *pMiniFat;
CDirectory *pDir;
CDIFat *pDIFat;
BOOL fixdf;
CFatVector *pfvFat, *pfvMiniFat;
wchar_t pwcsDocfile[_MAX_PATH];
DFLAGS df = DF_READWRITE | DF_DENYWRITE;
extern SCODE DllMultiStreamFromCorruptedStream(CMStream MSTREAM_NEAR **ppms,
ILockBytes **pplstStream,
DWORD dwFlags);
// Function Prototypes
void BuildFatTables();
void MarkFatTables();
void TreeWalk(CDirEntry *pde, SID sid);
BOOL GetOption(int argc, char *argv[]);
void Usage(char *pszProgName);
void DIFTable();
void main(int argc, char *argv[])
{
CFileStream *pfilestr;
CMStream MSTREAM_NEAR *pms;
SCODE scRc;
ILockBytes *pilb;
// if fixdf returns yes, open docfile without a copy;
// otherwise, open docfile with a copy and operate on the copy.
fixdf = GetOption(argc,argv);
pfilestr = new CFileStream;
// creating ILockBytes implementation for the given file
// Note: When a docfile is corrupted, the chkdsk utility
// calls the original CFileStream::Init. If any objects
// fail to instantiate, the approach is to call an
// alternative Init routine, which can force the instantiation
// of Directory and MiniFat objects.
if (fixdf==TRUE) // -f specified, write allowed.
{
df &= ~0x03;
df |= DF_WRITE;
printf("Trying to open file...\n");
scRc = pfilestr->Init(pwcsDocfile,RSF_OPEN,df);
if (FAILED(scRc))
{
printf("Error creating ILockBytes.\n");
exit(FAIL_CREATE_ILB);
}
}
else // open a read-only copy of filestream
{
df &= ~0x300; // clear access bits
df |= DF_DENYWRITE;
printf("Trying to open file...\n");
scRc = pfilestr->Init(pwcsDocfile,RSF_OPEN,df);
if (FAILED(scRc))
{
printf("Error creating ILockBytes.\n");
exit(FAIL_CREATE_ILB);
}
else printf("Successfully created ILockBytes.\n");
}
scRc = pfilestr->Validate();
if (scRc == STG_E_INVALIDHANDLE)
{
printf("Filestream signature is not valid.\n");
exit(INVALID_DOCFILE);
}
// CFileStream is essentially equivalent to ILockBytes.
pilb = (ILockBytes *) pfilestr;
scRc = DllMultiStreamFromStream(&pms,&pilb,0);
if (FAILED(scRc))
if (FAILED(scRc = DllMultiStreamFromCorruptedStream
(&pms,&pilb,0)))
{
exit(FAIL_CREATE_MULTISTREAM);
printf("Error creating a multistream.\n");
}
// When an multi-stream is instantiated, the following control structures
// are automatically instantiated.
pheader = pms->GetHeader();
pDir = pms->GetDir();
pFat = pms->GetFat();
pMiniFat = pms->GetMiniFat();
pDIFat = pms->GetDIFat();
printf("\tBuilding fat tables...\n");
BuildFatTables();
printf("\tExamining the DIFat...\n");
DIFTable();
printf("\tExamining Fat and MiniFat chains...\n");
MarkFatTables();
printf("\tChecking completed.\n");
delete(pfvFat);
delete(pfvMiniFat);
pfilestr->Release();
printf("Memory blocks freed.\n");
}
void BuildFatTables()
{
// Build two tables: one for Fat sectors, the other for Minifat sectors.
FSINDEX FatLen,MiniFatLen;
FatLen = pheader->GetFatLength();
MiniFatLen = pheader->GetMiniFatLength();
pfvFat = new CFatVector(TABLE_SIZE);
pfvFat->Init(FatLen);
if (MiniFatLen == 0)
printf("No MiniFat to be checked.\n");
else
{
pfvMiniFat = new CFatVector(TABLE_SIZE);
pfvMiniFat->Init(MiniFatLen);
}
}
void MarkFatTables()
{
CDirEntry *pde;
// Walk through all the fat chains and mark the new table with the
// first SID number encountered.
pDir->SidToEntry(SIDROOT,&pde);
TreeWalk(pde,SIDROOT); // pde points to the root entry now
}
void TreeWalk(CDirEntry *pde, SID sid)
{
CDirEntry *pchild, *pnext;
SID childsid, nextsid;
SCODE scRc,scRcM;
FSINDEX fitable,fioffset;
SECT sectentry, sect;
CFatSect *pfsec;
CFatVector *pfv;
CFat *pf;
ULONG uldesize;
pDir->GetStart(sid,&sect);
uldesize = pde->GetSize();
if (uldesize >= MINISTREAMSIZE) // storage is in FAT
{
pfv = pfvFat;
pf = pFat;
}
else
{
pfv = pfvMiniFat;
pf = pMiniFat;
}
// Check if LUID exceeds MaxLUID. If so, report the error.
if (pde->GetLuid() > pheader->GetLuid())
printf("LUID for dir entry #%lu exceeds MAXLuid.\n",sid);
while (sect < MAXREGSECT)
{
if (sid == SIDROOT)
break; // nothing should be in root stream
// Use fitable and fioffset to index into the fat (or minifat)
// table and mark the field with visited.
// at the same time, check for loops or crosslinks.
//Note: 3 cases
fitable = sect / (TABLE_SIZE);
fioffset = sect % (TABLE_SIZE);
pfv->GetTable(fitable,&pfsec); // pfsec = ptr to CFatSect
sectentry = pfsec->GetSect(fioffset);
// printf("\tsect = %lu \t \t sectentry = %lu \t stream_size = %lu\n",
// sect,sectentry, uldesize);
// Mark the FatTables as well as fixing the multistream.
// Right now, the routine only marks the FatTables.
//Note: 3 cases...but the last two cases may not
// be handled the same.
if (sectentry > MAXREGSECT)
pfsec->SetSect(fioffset,sid);
else if (sectentry == sid)
{
// discontinue the current stream chain by marking
// current SECT as ENDOFCHAIN.
pf->SetNext(sect,ENDOFCHAIN);
pfsec->SetSect(fioffset,ENDOFCHAIN);
printf("Loop detected at fat SECT %ul\n",sectentry);
}
else
{
pf->SetNext(sect,ENDOFCHAIN);
pfsec->SetSect(fioffset,ENDOFCHAIN);
printf("Crosslink detected at Fat SECT %lu with stream #%lu\n",
sect,sid);
}
// get the next sector to be examined
// !!!!! Need to use the Fat object to track down next sector
pf->GetNext(sect,&sect);
}
// Recursively go down the tree
// pchild and pnext must point to the original tree for
// efficiency purposes.
childsid = pde->GetChild();
if (childsid != NOSTREAM)
{
pDir->SidToEntry(childsid,&pchild);
TreeWalk(pchild,childsid);
}
nextsid = pde->GetNext();
if (nextsid != NOSTREAM)
{
pDir->SidToEntry(nextsid,&pnext);
TreeWalk(pnext,nextsid);
}
if (fixdf==TRUE)
{
scRc = pFat->Flush();
scRcM = pMiniFat->Flush();
if (FAILED(scRc) || FAILED(scRcM))
printf("Failed to write all modified FatSects out to stream.\n");
}
}
BOOL GetOption(int argc, char *argv[])
{
char *pszArg, *pszProgName;
BOOL ArgsOK = FALSE, Fix = FALSE;
pszProgName = *argv++;
while ((pszArg = *argv++) != NULL)
{
if (*pszArg == '-' || *pszArg == '/')
{
switch (tolower(*(++pszArg)))
{
case 'f': // fix the errors.
Fix = TRUE; // open file with read-only without a copy.
break;
case 'n': // name of the docfile to be opened.
// path of the filename.
mbstowcs(pwcsDocfile,++pszArg,_MAX_PATH);
Fix = FALSE;
ArgsOK = TRUE;
break;
default:
break;
}
}
else ArgsOK = FALSE;
}
if (ArgsOK == FALSE)
{
printf("0 argument or invalid command line argument.\n");
Usage(pszProgName);
exit(INVALID_ARG);
}
return Fix;
}
void Usage(char *pszProgName)
{
printf("Usage: %s\n", pszProgName);
printf(" -f fix requested by user.\n");
printf(" -n <name of docfile>\n");
printf("The -n option must be specified.\n");
}
void DIFTable() // August 11, 1992
{
// Walk through each DIF sector array to detect loops and
// crosslinks.
SCODE scRc;
BOOL FatOK = TRUE;
SECT sect, sectentry;
FSINDEX diflen, fatlen, fitable, fioffset, index, minifatlen,uldif,ulr;
CFatSect *pfsec;
diflen = pheader->GetDifLength();
fatlen = pheader->GetFatLength();
minifatlen = pheader->GetMiniFatLength();
// testing the validity of pheader->GetDifLength
if (fatlen > CSECTFAT) // diflen > 0
{
ulr = ( ((fatlen - CSECTFAT)%TABLE_SIZE) > 0 )? 1: 0;
uldif = CSECTFAT + (fatlen-CSECTFAT)/TABLE_SIZE + ulr;
}
else uldif = 0;
if (diflen!=uldif)
printf("DIFLEN in header is inconsistent with FatLEN.\n");
for (index=0; index<fatlen; index++)
{
pDIFat->GetFatSect(index,&sect);
if (sect < MAXREGSECT)
{
fitable = sect / TABLE_SIZE;
fioffset = sect % TABLE_SIZE;
pfvFat->GetTable(fitable,&pfsec); // pfsec = ptr to CFatSect
sectentry = pfsec->GetSect(fioffset);
if (sectentry > MAXREGSECT)
pfsec->SetSect(fioffset,SIDFAT);
else
{
printf("Crosslink! DIF index #%u points\n",index);
printf(" to the same location %u.\n", sect);
FatOK = FALSE;
}
}
pDIFat->GetFatSect(index+1,&sect);
}
if (FatOK == TRUE)
printf("No errors found in DIFat.\n");
// Walk through the terminating cells in each sector array to check
// the correctness of chaining.
printf("\tWalking through DIFTable chain.\n");
for (index = 0; index<diflen; index++)
{
pDIFat->GetSect(index,&sect);
fitable = sect/TABLE_SIZE;
fioffset = sect%TABLE_SIZE;
pfvFat->GetTable(fitable,&pfsec); // pfsec = ptr to CFatSect
sectentry = pfsec->GetSect(fioffset);
if ((sectentry!=ENDOFCHAIN) && (index == diflen-1))
printf("ERROR! ENDOFCHAIN expected at the end of DIFat.\n.");
pDIFat->SetFatSect(fioffset,SIDDIF);
pfsec->SetSect(fioffset,SIDDIF);
}
if (fixdf==TRUE)
{
scRc = pDIFat->FlushAll();
if (FAILED(scRc))
printf("Failed to write all modified FatSects out to stream.\n");
}
}