windows-nt/Source/XPSP1/NT/base/mvdm/dos/dem/demfile.c
2020-09-26 16:20:57 +08:00

1334 lines
35 KiB
C

/* demfile.c - SVC handlers for calls where file name is specified.
*
* demOpen
* demCreate
* demUnlink
* demChMod
* demRename
*
* Modification History:
*
* Sudeepb 02-Apr-1991 Created
*
*/
#include "dem.h"
#include "demmsg.h"
#include <softpc.h>
#include <winbase.h>
#include <vrnmpipe.h>
#include <nt_vdd.h>
extern PDOSSF pSFTHead;
BOOL (*VrInitialized)(VOID); // POINTER TO FUNCTION
extern BOOL LoadVdmRedir(VOID);
extern BOOL IsVdmRedirLoaded(VOID);
BOOL
IsNamedPipeName(
IN LPSTR Name
);
BOOL
IsNamedPipeName(
IN LPSTR Name
)
/*++
Routine Description:
Lifted from VDMREDIR.DLL - we don't want to load the entire DLL if we
need to check for a named pipe
Checks if a string designates a named pipe. As criteria for the decision
we use:
\\computername\PIPE\...
DOS (client-side) can only open a named pipe which is created at a server
and must therefore be prefixed by a computername
Arguments:
Name - to check for (Dos) named pipe syntax
Return Value:
BOOL
TRUE - Name refers to (local or remote) named pipe
FALSE - Name doesn't look like name of pipe
--*/
{
int CharCount;
if (IS_ASCII_PATH_SEPARATOR(*Name)) {
++Name;
if (IS_ASCII_PATH_SEPARATOR(*Name)) {
++Name;
CharCount = 0;
while (*Name && !IS_ASCII_PATH_SEPARATOR(*Name)) {
++Name;
++CharCount;
}
if (!CharCount || !*Name) {
//
// Name is \\ or \\\ or just \\name which I don't understand,
// so its not a named pipe - fail it
//
return FALSE;
}
//
// bump name past next path separator. Note that we don't have to
// check CharCount for max. length of a computername, because this
// function is called only after the (presumed) named pipe has been
// successfully opened, therefore we know that the name has been
// validated
//
++Name;
} else {
return FALSE;
}
//
// We are at <something> (after \ or \\<name>\). Check if <something>
// is [Pp][Ii][Pp][Ee][\\/]
//
if (!_strnicmp(Name, "PIPE", 4)) {
Name += 4;
if (IS_ASCII_PATH_SEPARATOR(*Name)) {
return TRUE;
}
}
}
return FALSE;
}
/* demOpen - Open a file
*
*
* Entry - Client (DS:SI) Full path of File
* Client (BL) Open Mode
* Client (ES:DI) Address of extended attributes buffer
* Client (AL) 0 - No EA's ; 1 - EA's specified
*
* Exit
* SUCCESS
* Client (CY) = 0
* Client (AX) = Assigned Open Handle (high word)
* Client (BP) = Assigned Open Handle (low word)
* Client (DX) = 1 if pipe was opened
* Client (BX) = High word of the file size
* Client (CX) = low word of the file size
*
*
* FAILURE
* CY = 1
* AX = system status code
* HARD ERROR
* CY = 1
* AX = 0FFFFh
*
*
* Notes : Extended Attributes is not yet taken care of.
*/
VOID demOpen (VOID)
{
HANDLE hFile;
LPSTR lpFileName;
UCHAR uchMode,uchAccess;
DWORD dwDesiredAccess = GENERIC_WRITE | GENERIC_READ;
DWORD dwShareMode = FILE_SHARE_READ | FILE_SHARE_WRITE;
BOOL ItsANamedPipe = FALSE;
BOOL IsFirst;
LPSTR dupFileName;
DWORD dwFileSize,dwSizeHigh;
SECURITY_ATTRIBUTES sa;
if (getAL()){
demPrintMsg (MSG_EAS);
return;
}
lpFileName = (LPSTR) GetVDMAddr (getDS(),getSI());
#if DBG
if(fShowSVCMsg & DEMFILIO){
sprintf(demDebugBuffer,"demfile: Opening File <%s>\n",lpFileName);
OutputDebugStringOem(demDebugBuffer);
}
#endif
//
// the DOS filename must be 'canonicalized': forward slashes (/) must be
// converted to back slashes (\) and the filename should be upper-cased
// using the current code page info
//
//
// BUBUG: Kanji? (/other DBCS)
//
if (strchr(lpFileName, '/')) {
char ch= *lpFileName;
lpFileName = _strdup(lpFileName);
if (lpFileName == NULL) {
SetLastError(ERROR_NOT_ENOUGH_MEMORY);
demClientError(INVALID_HANDLE_VALUE, ch);
return;
}
for (dupFileName = lpFileName; *dupFileName; ++dupFileName) {
if (*dupFileName == '/') {
*dupFileName = '\\';
}
}
dupFileName = lpFileName;
} else {
dupFileName = NULL;
}
uchMode = getBL();
uchAccess = uchMode & (UCHAR)ACCESS_MASK;
if (uchAccess == OPEN_FOR_READ)
dwDesiredAccess = GENERIC_READ;
else if (uchAccess == OPEN_FOR_WRITE)
dwDesiredAccess = GENERIC_WRITE;
uchMode = uchMode & (UCHAR)SHARING_MASK;
switch (uchMode) {
case SHARING_DENY_BOTH:
dwShareMode = 0;
break;
case SHARING_DENY_WRITE:
dwShareMode = FILE_SHARE_READ;
break;
case SHARING_DENY_READ:
dwShareMode = FILE_SHARE_WRITE;
break;
}
//
// slightly new scheme - the redir isn't automatically loaded anymore. We
// may perform a named pipe operation before VDMREDIR is loaded. So now we
// load VDMREDIR.DLL if the filespec designates a named pipe
//
if (IsNamedPipeName(lpFileName)) {
if (!LoadVdmRedir()) {
goto errorReturn;
}
ItsANamedPipe = TRUE;
//
// convert \\<this_computer>\PIPE\foo\bar\etc to \\.\PIPE\...
// if we already allocated a buffer for the slash conversion use
// that else this call will allocate another buffer (we don't
// want to write over DOS memory)
//
lpFileName = VrConvertLocalNtPipeName(dupFileName, lpFileName);
if (!lpFileName) {
goto errorReturn;
}
}
//
// open the file. If we think its a named pipe then use FILE_FLAG_OVERLAPPED
// because the client might use DosReadAsyncNmPipe or DosWriteAsyncNmPipe
// and the only way to accomplish that is to open the named pipe handle in
// overlapped I/O mode now
//
// sudeepb 26-Apr-1993 We are retrying opening the file in case
// of failure without GENERIC_WRITE because of the incompatibility
// of DOS and NT CD ROM driver. DOS CDROM driver ignores the write
// bit which we have to fakeout in this way.
sa.nLength = sizeof (SECURITY_ATTRIBUTES);
sa.lpSecurityDescriptor = NULL;
sa.bInheritHandle = TRUE;
IsFirst = TRUE;
while (TRUE) {
if ((hFile = CreateFileOem(lpFileName,
dwDesiredAccess,
dwShareMode | FILE_SHARE_DELETE,
&sa,
OPEN_EXISTING,
ItsANamedPipe ? FILE_FLAG_OVERLAPPED : 0,
NULL)) == (HANDLE)-1){
if (IsFirst && dwDesiredAccess & GENERIC_WRITE &&
IsCdRomFile(lpFileName)) {
dwDesiredAccess &= ~GENERIC_WRITE;
IsFirst = FALSE;
continue;
}
errorReturn:
demClientError(INVALID_HANDLE_VALUE, *lpFileName);
if (dupFileName) {
free(dupFileName);
} else if (ItsANamedPipe && lpFileName) {
LocalFree(lpFileName);
}
return;
}
else
break;
}
//
// we have to keep some info around when we open a named pipe
//
if (ItsANamedPipe) {
VrAddOpenNamedPipeInfo(hFile, lpFileName);
setDX(1);
}
else {
if(((dwFileSize=GetFileSize(hFile,&dwSizeHigh)) == (DWORD)-1) ||
dwSizeHigh) {
CloseHandle (hFile);
demClientError(INVALID_HANDLE_VALUE, *lpFileName);
return;
}
setCX ((USHORT)dwFileSize);
setBX ((USHORT)(dwFileSize >> 16 ));
setDX(0);
}
setBP((USHORT)hFile);
setAX((USHORT)((ULONG)hFile >> 16));
setCF(0);
if (dupFileName) {
free(dupFileName);
} else if (ItsANamedPipe) {
LocalFree(lpFileName);
}
return;
}
#define DEM_CREATE 0
#define DEM_CREATE_NEW 1
/* demCreate - Create a file
*
*
* Entry - Client (DS:SI) Full path of File
* Client (CX) Attributes
* 00 - Normal File
* 01 - Read-only file
* 02 - Hidden File
* 04 - System file
*
* Exit
* SUCCESS
* Client (CY) = 0
* Client (AX) = Assigned Open Handle (high word)
* VSF(BP) = Assigned Open Handle (low word)
*
* FAILURE
* CY = 1
* AX = error code
* HARD ERROR
* CY = 1
* AX = 0FFFFh
*
*/
VOID demCreate (VOID)
{
demCreateCommon (DEM_CREATE);
return;
}
/* demCreateNew - Create a New file
*
*
* Entry - Client (DS:SI) Full path of File
* Client (CX) Attributes
* 00 - Normal File
* 01 - Read-only file
* 02 - Hidden File
* 04 - System file
*
* Exit
* SUCCESS
* Client (CY) = 0
* Client (AX) = Assigned Open Handle (high word)
* VSF(BP) = Assigned Open Handle (low word)
*
* FAILURE
* CY = 1
* AX = error code
* HARD ERROR
* CY = 1
* AX = 0FFFFh
*
*/
VOID demCreateNew (VOID)
{
demCreateCommon (DEM_CREATE_NEW);
return;
}
/* demFileDelete
*
* EXPORTED FUNCTION
*
* ENTRY:
* lpFile -> OEM file name to be deleted
*
* EXIT:
* returns 0 on success, DOS error code on failure
*
* NOTES:
* Some apps keep a file open and delete it. Then rename another file to
* the old name. On NT since the orignal object is still open the second
* rename fails.
* To get around this problem we rename the file before deleteing it
* this allows the second rename to work
*
* But since renaming the file is known to be expensive over the net, we try
* first to open the file exclusively to see if there is really any reason to
* rename it. If we can get a handle to it, then we should be able to skip the
* rename and just delete it. If we can't get a handle to it, then we try
* the rename trick. This should cut down our overhead for the normal case.
*/
DWORD demFileDelete (LPSTR lpFile)
{
CHAR vdmtemp[MAX_PATH];
CHAR tmpfile[MAX_PATH];
PSZ pFileName;
HANDLE hFile;
//
// First, try to access the file exclusively
//
hFile = CreateFileOem(lpFile,
DELETE,
0,
NULL,
OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL,
NULL);
if (hFile != INVALID_HANDLE_VALUE) {
NTSTATUS status;
IO_STATUS_BLOCK ioStatusBlock;
FILE_DISPOSITION_INFORMATION fileDispositionInformation;
// Member name "DeleteFile" conflicts with win32 definition (it
// becomes "DeleteFileA".
#undef DeleteFile
fileDispositionInformation.DeleteFile = TRUE;
//
// We got a handle to it, so there can't be any open
// handles to it. Set the disposition to DELETE.
//
status = NtSetInformationFile(hFile,
&ioStatusBlock,
&fileDispositionInformation,
sizeof(FILE_DISPOSITION_INFORMATION),
FileDispositionInformation);
CloseHandle(hFile);
if NT_SUCCESS(status) {
SetLastError(NO_ERROR);
} else {
SetLastError(ERROR_ACCESS_DENIED);
}
}
//
// Check to see if the delete went OK. If not, try renaming
// the file.
//
switch (GetLastError()) {
case NO_ERROR:
case ERROR_FILE_NOT_FOUND:
case ERROR_PATH_NOT_FOUND:
// Can't find it, forget about it
break;
case ERROR_SHARING_VIOLATION:
case ERROR_ACCESS_DENIED:
//
// The file didn't really go away because there appears to
// be an open handle to the file.
//
if (GetFullPathNameOem(lpFile,MAX_PATH,vdmtemp,&pFileName)) {
if ( pFileName )
*(pFileName) = 0;
if (GetTempFileNameOem(vdmtemp,"VDM",0,tmpfile)) {
if (MoveFileExOem(lpFile,tmpfile, MOVEFILE_REPLACE_EXISTING)) {
if(DeleteFileOem(tmpfile)) {
SetLastError(NO_ERROR);
} else {
MoveFileOem(tmpfile,lpFile);
SetLastError(ERROR_ACCESS_DENIED);
}
}
}
}
break;
default:
//
// We couldn't open or delete the file, and it's not because of a
// sharing violation. Just try a last ditch effort of a
// plain old delete, and see if it works.
//
if(DeleteFileOem(lpFile)) {
SetLastError(NO_ERROR);
}
}
//
// Map win32 error code to DOS
//
switch(GetLastError()) {
case NO_ERROR:
case ERROR_FILE_NOT_FOUND:
case ERROR_PATH_NOT_FOUND:
case ERROR_ACCESS_DENIED:
break;
default:
// make sure demClientError can see retval
SetLastError(ERROR_ACCESS_DENIED);
}
return GetLastError();
}
/* demDelete - Delete a file
*
*
* Entry - Client (DS:DX) Full path of File
*
* Exit
* SUCCESS
* Client (CY) = 0
*
* FAILURE
* CY = 1
* AX = system status code
* HARD ERROR
* CY = 1
* AX = 0FFFFh
*
*/
VOID demDelete (VOID)
{
LPSTR lpFileName;
DWORD retval;
lpFileName = (LPSTR) GetVDMAddr (getDS(),getDX());
#if DBG
if(fShowSVCMsg & DEMFILIO){
sprintf(demDebugBuffer,"demfile: Deleting File<%s>\n",lpFileName);
OutputDebugStringOem(demDebugBuffer);
}
#endif
if (retval = demFileDelete(lpFileName)){
demClientError(INVALID_HANDLE_VALUE, *lpFileName);
return;
}
setCF(0);
return;
}
/* demChMod - Change the file modes
*
* Entry - Client (DS:DX) Full path of File
* Client (AL) = 0 Get File Modes 1 Set File Modes
* Client (CL) new modes
*
* Exit
* SUCCESS
* Client (CY) = 0
* Client (CL) = file attributes in get case.
*
* FAILURE
* Client (CY) = 1
* Client (AX) = Error Code
* HARD ERROR
* CY = 1
* AX = 0FFFFh
*
* Compatibility Notes:
*
* ATTR_VOLUME_ID,ATTR_DEVICE and ATTR_DIRECTORY are not supported
* by WIN32 call. Although these are unpublished for DOS world also
* but still a compatibility requirement.
*/
VOID demChMod (VOID)
{
LPSTR lpFileName;
DWORD dwAttr;
lpFileName = (LPSTR) GetVDMAddr (getDS(),getDX());
#if DBG
if(fShowSVCMsg & DEMFILIO){
sprintf(demDebugBuffer,"demfile: ChMod File <%s>\n",lpFileName);
OutputDebugStringOem(demDebugBuffer);
}
#endif
if(getAL() == 0){
if ((dwAttr = GetFileAttributesOem(lpFileName)) == -1)
goto dcerr;
if (dwAttr == FILE_ATTRIBUTE_NORMAL) {
dwAttr = 0;
}
else {
dwAttr &= DOS_ATTR_MASK;
}
// SudeepB - 28-Jul-1997
//
// For CDFS, Win3.1/DOS/Win95, only return FILE_ATTRIBUTE_DIRECTORY (10)
// for directories while WinNT returns
// FILE_ATTRIBUTE_DIRECTORY | FILE_ATTRIBUTE_READONLY (11).
// Some VB controls that app setups use, depend on getting
// FILE_ATTRIBUTE_DIRECTORY (10) only or otherwise are broken.
// An example of this is Cliffs StudyWare series.
if (dwAttr == (FILE_ATTRIBUTE_DIRECTORY | FILE_ATTRIBUTE_READONLY)) {
if(IsCdRomFile(lpFileName))
dwAttr = FILE_ATTRIBUTE_DIRECTORY;
}
setCX((USHORT)dwAttr);
setCF(0);
return;
}
if((dwAttr = getCX()) == 0)
dwAttr = FILE_ATTRIBUTE_NORMAL;
dwAttr &= DOS_ATTR_MASK;
if (!SetFileAttributesOem(lpFileName,dwAttr))
goto dcerr;
setCF(0);
return;
dcerr:
demClientError(INVALID_HANDLE_VALUE, *lpFileName);
return;
}
/* demRename - Rename a file
*
* Entry - Client (DS:DX) Source File
* Client (ES:DI) Destination File
*
* Exit
* SUCCESS
* Client (CY) = 0
*
* FAILURE
* Client (CY) = 1
* Client (AX) = Error Code
*
*/
VOID demRename (VOID)
{
LPSTR lpSrc,lpDst;
lpSrc = (LPSTR) GetVDMAddr (getDS(),getDX());
lpDst = (LPSTR) GetVDMAddr (getES(),getDI());
#if DBG
if(fShowSVCMsg & DEMFILIO){
sprintf(demDebugBuffer,"demfile: Rename File <%s> to <%s>\n",lpSrc,lpDst);
OutputDebugStringOem(demDebugBuffer);
}
#endif
// DOS rename fails accross drives with 11h error code
// This following check is OK even for UNC names and SUBST drives.
// SUBST drives come to NTVDM as env variables for current directory
// and we will treet them just like a network drive and full qualified
// path will be sent from NTDOS.
if(toupper(lpSrc[0]) != toupper(lpDst[0])) {
setCF(1);
setAX(0x11);
return;
}
// Now check that SRC and DEST are not pointing to the same file.
// if they do return error 5.
if (!_stricmp (lpSrc, lpDst)) {
setCF(1);
setAX(0x5);
return;
}
if(MoveFileOem(lpSrc,lpDst) == FALSE){
demClientError(INVALID_HANDLE_VALUE, *lpSrc);
return;
}
setCF(0);
return;
}
/* demCreateCommon - Create a file or Craete a new file
*
*
* Entry - flCreateType - DEM_CREATE_NEW create new
* DEM_CREATE create
*
* Exit
* SUCCESS
* Client (CY) = 0
* Client (AX) = Assigned Open Handle (high word)
* Client (BP) = Assigned Open Handle (low word)
*
* FAILURE
* CY = 1
* AX = error code
* HARD ERROR
* CY = 1
* AX = 0FFFFh
*
*/
VOID demCreateCommon (flCreateType)
ULONG flCreateType;
{
HANDLE hFile;
LPSTR lpFileName;
LPSTR lpDot;
DWORD dwAttr;
DWORD dwFileSize,dwSizeHigh;
USHORT uErr;
DWORD dwDesiredAccess;
SECURITY_ATTRIBUTES sa;
CHAR cFOTName[MAX_PATH];
BOOL ttfOnce,IsFirst;
DWORD dwLastError;
lpFileName = (LPSTR) GetVDMAddr (getDS(),getSI());
dwAttr = (DWORD)getCX();
// Here is some code stolen from DOS_Create (create.asm) for handling the
// attributes
if (flCreateType == DEM_CREATE || flCreateType == DEM_CREATE_NEW)
dwAttr &= 0xff;
if (dwAttr & ~(ATTR_ALL | ATTR_IGNORE | ATTR_VOLUME_ID)) {
setCF(1);
setAX(5); //Attribute problem
return;
}
/* Special case for set volume label (INT 21 Func 3CH, Attr = 8H */
if((flCreateType == DEM_CREATE || flCreateType == DEM_CREATE_NEW) && (dwAttr == ATTR_VOLUME_ID)) {
if((uErr = demCreateLabel(lpFileName[DRIVEBYTE],
lpFileName+LABELOFF))) {
setCF(1);
setAX(uErr);
return;
}
setAX(0);
setBP(0); // in this case handle = 0 and if we will
setCF(0); // close this handle CF will be 0(!)
return;
}
if ((dwAttr & 0xff) == 0) {
dwAttr = FILE_ATTRIBUTE_NORMAL;
} else {
dwAttr &= DOS_ATTR_MASK;
}
#if DBG
if(fShowSVCMsg & DEMFILIO){
sprintf(demDebugBuffer,"demfile: Creating File <%s>\n",lpFileName);
OutputDebugStringOem(demDebugBuffer);
}
#endif
dwDesiredAccess = GENERIC_WRITE | GENERIC_READ;
sa.nLength = sizeof (SECURITY_ATTRIBUTES);
sa.lpSecurityDescriptor = NULL;
sa.bInheritHandle = TRUE;
ttfOnce = TRUE;
IsFirst = TRUE;
while (TRUE) {
if ((hFile = CreateFileOem(lpFileName,
// create file with delete access and sharing mode
// so that anybody can delete it without closing
// the file handle returned from create file
dwDesiredAccess,
FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
&sa,
flCreateType == DEM_CREATE ? CREATE_ALWAYS : CREATE_NEW,
dwAttr,
NULL)) == (HANDLE)-1){
if (IsFirst && dwDesiredAccess & GENERIC_WRITE &&
IsCdRomFile(lpFileName)) {
dwDesiredAccess &= ~GENERIC_WRITE;
IsFirst = FALSE;
continue;
}
// APP COMPATABILITY
// Some WOW apps installing .TTF or .FON or Fonts fail to create
// The file because the font is already open by GDI32 server.
// The install/setup programs don't gracefully handle
// this error, they bomb out of the install with retry or cancel
// without offering the user a way to ignore the error (which
// would be the right thing since the font already exists.
// To work around this problem we do a RemoveFontResource here
// which causes GDI32 to unmap the file, we then retry
// the create. - mattfe june 93
// If it is a TTF file then we need to remove the font resource
// for the .FOT file of the same name
if (ttfOnce) {
// Look for the file extension
lpDot = strrchr(lpFileName,'.');
if (lpDot) {
if ( (!_strcmpi(lpDot,".TTF")) ||
(!_strcmpi(lpDot,".FON")) ||
(!_strcmpi(lpDot,".FOT")) ) {
if ( RemoveFontResourceOem(lpFileName) ) {
PostMessage(HWND_BROADCAST, WM_FONTCHANGE, 0, 0);
ttfOnce = FALSE;
continue;
}
// We failed to remove the .TTF file probably because
// the .FOT file was loaded, so try to remove it
if (!_strcmpi(lpDot,".TTF")) {
RtlZeroMemory(cFOTName,sizeof(cFOTName));
RtlCopyMemory(cFOTName,lpFileName,(ULONG)lpDot-(ULONG)lpFileName);
strcat(cFOTName,".FOT");
if ( RemoveFontResourceOem(cFOTName) ) {
PostMessage(HWND_BROADCAST, WM_FONTCHANGE, 0, 0);
ttfOnce = FALSE;
continue;
}
}
}
}
}
demClientError(INVALID_HANDLE_VALUE, *lpFileName);
return;
}
else
break;
}
if((dwFileSize=GetFileSize(hFile,&dwSizeHigh) == -1) || dwSizeHigh) {
CloseHandle (hFile);
demClientError(INVALID_HANDLE_VALUE, *lpFileName);
return;
}
setCX ((USHORT)dwFileSize);
setBX ((USHORT)(dwFileSize >> 16 ));
setBP((USHORT)hFile);
setAX((USHORT)((ULONG)hFile >> 16));
setCF(0);
return;
}
BOOL IsCdRomFile (PSTR pszPath)
{
UCHAR pszRootDir[MAX_PATH];
UCHAR file_system[MAX_PATH];
int i, j;
// The given path is either a network path or has D: at the start.
if (!pszPath[0]) {
return FALSE;
}
if (pszPath[1] == ':') {
pszRootDir[0] = pszPath[0];
pszRootDir[1] = ':';
pszRootDir[2] = '\\';
pszRootDir[3] = 0;
} else if (IS_ASCII_PATH_SEPARATOR(pszPath[0]) &&
IS_ASCII_PATH_SEPARATOR(pszPath[1])) {
j = 0;
for (i = 2; pszPath[i]; i++) {
if (IS_ASCII_PATH_SEPARATOR(pszPath[i])) {
if (++j == 2) {
break;
}
}
}
memcpy(pszRootDir, pszPath, i);
pszRootDir[i] = '\\';
pszRootDir[i+1] = 0;
} else {
return FALSE;
}
if (GetVolumeInformationOem(pszRootDir, NULL, 0, NULL, NULL, NULL,
file_system, MAX_PATH) &&
!_stricmp(file_system, "CDFS")) {
return TRUE;
}
return FALSE;
}
/* demCheckPath - Check path (for device only)
*
*
* Entry - Client (DS:SI) Full path (with last '\')
*
* Exit
* SUCCESS
* Client (CF) = 0
*
* FAILURE
* CF = 1
*/
VOID demCheckPath (VOID)
{
HANDLE hFile;
LPSTR lpFileName;
CHAR cDRV;
CHAR szFileName[MAX_PATH];
lpFileName = (LPSTR) GetVDMAddr (getDS(),getSI());
cDRV = getDL()+'A'-1;
setDX(0);
// If we have \dev dir then return OK, DOS always has this directory for
// devices.
if(!lstrcmpi(lpFileName, "\\DEV\\")) {
setCF(0);
return;
}
sprintf(szFileName, "%c:%sNUL", cDRV, lpFileName);
#if DBG
if(fShowSVCMsg & DEMFILIO){
sprintf(demDebugBuffer,"demfile: Check Pathe <%s>\n",lpFileName);
OutputDebugStringOem(demDebugBuffer);
}
#endif
// If path exists then we always can open NUL file in this directory,
// if path doesn't exists then CreateFile returns INVALID_HANDLE_VALUE
//
if ((hFile = CreateFileOem((LPSTR) szFileName,
GENERIC_WRITE,
FILE_SHARE_READ | FILE_SHARE_WRITE,
NULL,
CREATE_ALWAYS,
FILE_ATTRIBUTE_NORMAL,
NULL)) == INVALID_HANDLE_VALUE) {
demClientError(INVALID_HANDLE_VALUE, *lpFileName);
setCF(1);
return;
}
CloseHandle (hFile);
setCF(0);
return;
}
PDOSSFT GetFreeSftEntry(PDOSSF pSfHead, PWORD usSFN)
{
WORD i;
PDOSSFT pSft;
DWORD ulSFLink;
*usSFN = 0;
for (;;) {
pSft = (PDOSSFT) &(pSfHead->SFTable);
for (i = 0; i < pSfHead->SFCount; i++) {
if (pSft[i].SFT_Ref_Count == 0) {
*usSFN += i;
return (pSft + i);
}
}
*usSFN += pSfHead->SFCount;
ulSFLink = pSfHead->SFLink;
if (LOWORD(ulSFLink) == 0xFFFF) {
break;
}
pSfHead = (PDOSSF) Sim32GetVDMPointer (ulSFLink, 0, 0);
}
return NULL;
}
/** VDDAllocateDosHandle - Allocates an unused DOS file handle.
*
* ENTRY -
* IN pPDB - OPTIONAL: (16:16) address of the PDB for the task
* OUT ppSFT - OPTIONAL: Returns a 32-bit flat pointer to the SFT
* associated with the allocated file handle.
* OUT ppJFT - OPTIONAL: Returns a 32-bit flat pointer to the JFT
* associated with the given PDB.
*
*
* EXIT
* SUCCESS - Returns the value of the DOS file handle and associated
* pointers.
* FAILURE - Returns a negative value. The absolute value of this number
* is the DOS error code.
*
* Comments:
* This routine searches for an unused DOS file handle and SFT and "opens"
* a file. After the successful completion of this call, the returned file
* handle and the corresponding SFT will be reserved for the caller's use, and
* will be unavailable to other callers trying to issue DOS Open or Create api
* calls. It is the caller's responsibility to release this file handle (with
* a call to VDDReleaseDosHandle).
*
* If the pPDB pointer is not supplied (e.g., is NULL), then the current
* PDB as reported by DOS will be used.
*
* Although the ppSFT parameter is technically optional, it is a required
* parameter of the VDDAssociateNtHandle call. This was done to avoid a
* second handle lookup in the Associate call.
*
*/
SHORT VDDAllocateDosHandle (pPDB,ppSFT,ppJFT)
ULONG pPDB;
PDOSSFT* ppSFT;
PBYTE* ppJFT;
{
PDOSPDB pPDBFlat;
PBYTE pJFT;
PDOSSFT pSFT;
USHORT usSFN;
WORD JFTLength;
SHORT hDosHandle;
if (!pPDB) {
pPDB = (ULONG) (*pusCurrentPDB) << 16;
}
//
// Get the JFT.
//
pPDBFlat = (PDOSPDB) Sim32GetVDMPointer (pPDB, 0, 0);
if ( NULL == pPDBFlat ) {
return (- ERROR_INVALID_HANDLE);
}
pJFT = (PBYTE) Sim32GetVDMPointer (pPDBFlat->PDB_JFN_Pointer, 0, 0);
if ( NULL == pJFT ) {
return (- ERROR_INVALID_HANDLE);
}
//
// Check to see if there's a free entry in the JFT.
//
JFTLength = pPDBFlat->PDB_JFN_Length;
for (hDosHandle = 0; hDosHandle < JFTLength; hDosHandle++) {
if (pJFT[hDosHandle] == 0xFF) {
break;
}
}
// If no room in the JFT then return ERROR_TOO_MANY_OPEN_FILES
if (hDosHandle == JFTLength) {
return (- ERROR_TOO_MANY_OPEN_FILES);
}
//
// Check the SF for a free SFT.
//
if (!(pSFT = GetFreeSftEntry(pSFTHead, &usSFN))) {
return (- ERROR_TOO_MANY_OPEN_FILES);
}
pJFT[hDosHandle] = (BYTE)usSFN;
RtlZeroMemory((PVOID)pSFT, sizeof(DOSSFT));
pSFT->SFT_Ref_Count = 1;
if (ppSFT) {
*ppSFT = (pSFT);
}
if (ppJFT) {
*ppJFT = pJFT;
}
return(hDosHandle);
}
/** VDDAssociateNtHandle - Associates the passed NT handle and access flags
* the given DOS handle.
*
* ENTRY -
* IN pSFT - flat address of the SFT to be updated
* IN hFile32 - NT handle to be stored
* IN wAccess - access flags to set in the SFT
*
* EXIT -
* This routine has no return value.
*
* Comments:
* This routine takes the passed NT handle value and stores it in a DOS SFT
* so that it can later be retrieved by the VDDRetrieveNtHandle api. The
* pointer to the SFT is returned by the VDDAllocateDosHandle api.
*
* The format of the third parameter is the same as the file access flags
* defined for DOS Open File with Handle call (Int 21h, func 3dh), documented
* in Microsoft MS-DOS Programmer's Reference. Only the low order byte of
* this parameter is used, the upper byte is reserved and must be zero.
* The value of this parameter is placed into the passed SFT. This is provided
* to allow the caller to define the access rights for the corresponding
* DOS file handle.
*
*/
VOID VDDAssociateNtHandle (pSFT,hFile,wAccess)
PDOSSFT pSFT;
HANDLE hFile;
WORD wAccess;
{
pSFT->SFT_Mode = wAccess&0x7f; // take out no_inherit bit
pSFT->SFT_Attr = 0; // Not used.
pSFT->SFT_Flags = (wAccess&0x80) ? 0x1000 : 0; // copy no_inherit bit.
pSFT->SFT_Devptr = (ULONG) -1;
pSFT->SFT_NTHandle = (ULONG) hFile;
}
/** VDDReleaseDosHandle - Release the given DOS file handle.
*
* ENTRY -
* IN pPDB - OPTIONAL: (16:16) address of the PDB for the task
* IN hFile - DOS handle (in low byte)
*
* EXIT -
* TRUE - the file handle was released
* FALSE - The file handle was not valid or open
*
* Comments:
* This routine updates the DOS file system data areas to free the passed
* file handle. No effort is made to determine if this handle was previously
* opened by the VDDAllocateDosHandle call. It is the responsibility of the
* caller to insure that the given file handle in the specified PDB should
* be closed.
*
* If the pPDB pointer is not supplied (e.g., is NULL), then the current
* PDB as reported by DOS will be used.
*
*/
BOOL VDDReleaseDosHandle (pPDB,hFile)
ULONG pPDB;
SHORT hFile;
{
PBYTE pJFT;
PDOSSFT pSFT;
HANDLE ntHandle;
if (!pPDB) {
pPDB = (ULONG) (*pusCurrentPDB) << 16;
}
ntHandle = VDDRetrieveNtHandle(pPDB,hFile,(PVOID *)&pSFT,&pJFT);
if (!ntHandle) {
return(FALSE);
}
pJFT[hFile] = 0xFF;
// Decrement reference count.
pSFT->SFT_Ref_Count--;
return(TRUE);
}
/** VDDRetrieveNtHandle - Given a DOS file handle get the associated
* NT handle.
*
* ENTRY -
* IN pPDB - OPTIONAL: (16:16) address of the PDB for the task
* IN hFile - DOS handle (in low byte)
* OUT ppSFT - OPTIONAL: Returns a 32-bit flat pointer to the SFT
* associated with the given file.
* OUT ppJFT - OPTIONAL: Returns a 32-bit flat pointer to the JFT
* associated with the given PDB.
*
*
* EXIT -
* SUCCESS - returns 4byte NT handle
* FAILURE - returns 0
*
* Comments:
* The value returned by this function will be the NT handle passed in a
* previous VDDAssociateNtHandle call. If no previous call is made to the
* the Associate api, then the value returned by this function is undefined.
*
* If the pPDB pointer is not supplied (e.g., is NULL), then the current
* PDB as reported by DOS will be used.
*
* Although the ppSFT parameter is technically optional, it is a required
* parameter of the VDDAssociateNtHandle call. This was done to avoid a
* second handle lookup in the Associate call.
*
* The third and fourth parameters are provided to provide the caller the
* ability to update the DOS system data areas directly. This may be useful
* for performance reasons, or necessary depending on the application. In
* general, care must be taken when using these pointers to avoid causing
* system integrity problems.
*
*/
HANDLE VDDRetrieveNtHandle (pPDB,hFile,ppSFT,ppJFT)
ULONG pPDB;
SHORT hFile;
PDOSSFT* ppSFT;
PBYTE* ppJFT;
{
PDOSPDB pPDBFlat;
PDOSSF pSfFlat;
PDOSSFT pSftFlat;
PBYTE pJFT;
USHORT usSFN;
USHORT usSFTCount;
ULONG ulSFLink;
if (!pPDB) {
pPDB = (ULONG) (*pusCurrentPDB) << 16;
}
// Get flat pointer to PDB
pPDBFlat = (PDOSPDB) Sim32GetVDMPointer(pPDB, 0, 0);
// Check that handle is within JFT
if (hFile >= pPDBFlat->PDB_JFN_Length) {
return 0;
}
// Get the pointer to JFT
pJFT = (PBYTE) Sim32GetVDMPointer (pPDBFlat->PDB_JFN_Pointer, 0, 0);
// Get the SFN, remember -1 indicates unused JFT
usSFN = (USHORT) pJFT[hFile];
if (usSFN == 0xff) {
return 0;
}
// Get flat pointer to SF
pSfFlat = pSFTHead;
// Find the right SFT group
while (usSFN >= (usSFTCount = pSfFlat->SFCount)){
usSFN = usSFN - usSFTCount;
ulSFLink = pSfFlat->SFLink;
if (LOWORD(ulSFLink) == 0xffff)
return 0;
pSfFlat = (PDOSSF) Sim32GetVDMPointer (ulSFLink, 0, 0);
}
// Get the begining of SFT
pSftFlat = (PDOSSFT)&(pSfFlat->SFTable);
// Get the SFN, Finally
if(pSftFlat[usSFN].SFT_Ref_Count == 0) {
return 0;
}
if (ppSFT) {
*ppSFT = (pSftFlat + usSFN);
}
if (ppJFT) {
*ppJFT = pJFT;
}
return (HANDLE) pSftFlat[usSFN].SFT_NTHandle;
}