dos.h File Reference

#include "device.h"
#include "int32.h"

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Classes
struct	_DOS_FCB
struct	_DOS_SYSVARS
struct	_DOS_CLOCK_TRANSFER_RECORD
struct	_DOS_INPUT_BUFFER
struct	_DOS_FIND_FILE_BLOCK
struct	_DOS_SDA
struct	_DOS_DATA
struct	_BIOS_DATA

Macros
#define	DOS_VERSION   MAKEWORD(5, 00)
#define	NTDOS_VERSION   MAKEWORD(5, 50)
#define	DOS_CONFIG_PATH   L"%SystemRoot%\\system32\\CONFIG.NT"
#define	DOS_COMMAND_INTERPRETER   L"%SystemRoot%\\system32\\COMMAND.COM /k %SystemRoot%\\system32\\AUTOEXEC.NT"
#define	BIOS_CODE_SEGMENT   0x70
#define	BIOS_DATA_SEGMENT   0x70
#define	DOS_CODE_SEGMENT   0x80
#define	DOS_DATA_SEGMENT   0xA5
#define	DOS_DATA_OFFSET(x)   FIELD_OFFSET(DOS_DATA, x)
#define	SYSTEM_ENV_BLOCK   0x600
#define	SYSTEM_PSP   0x0008
#define	INVALID_DOS_HANDLE   0xFFFF
#define	DOS_INPUT_HANDLE   0
#define	DOS_OUTPUT_HANDLE   1
#define	DOS_ERROR_HANDLE   2
#define	DOS_SFT_SIZE   255
#define	DOS_DIR_LENGTH   64
#define	NUM_DRIVES   ('Z' - 'A' + 1)
#define	DOS_CHAR_ATTRIBUTE   0x07
#define	RegisterDosInt32(IntNumber, IntHandler)

Typedefs
typedef struct _DOS_FCB	DOS_FCB
typedef struct _DOS_FCB *	PDOS_FCB
typedef struct _DOS_SYSVARS	DOS_SYSVARS
typedef struct _DOS_SYSVARS *	PDOS_SYSVARS
typedef struct _DOS_CLOCK_TRANSFER_RECORD	DOS_CLOCK_TRANSFER_RECORD
typedef struct _DOS_CLOCK_TRANSFER_RECORD *	PDOS_CLOCK_TRANSFER_RECORD
typedef struct _DOS_INPUT_BUFFER	DOS_INPUT_BUFFER
typedef struct _DOS_INPUT_BUFFER *	PDOS_INPUT_BUFFER
typedef struct _DOS_FIND_FILE_BLOCK	DOS_FIND_FILE_BLOCK
typedef struct _DOS_FIND_FILE_BLOCK *	PDOS_FIND_FILE_BLOCK
typedef struct _DOS_SDA	DOS_SDA
typedef struct _DOS_SDA *	PDOS_SDA
typedef struct _DOS_DATA	DOS_DATA
typedef struct _DOS_DATA *	PDOS_DATA
typedef struct _BIOS_DATA	BIOS_DATA
typedef struct _BIOS_DATA *	PBIOS_DATA

Functions
	C_ASSERT (sizeof(BIOS_DATA)==0x100)
VOID	ConDrvInitialize (VOID)
VOID	ConDrvCleanup (VOID)
CHAR	DosReadCharacter (WORD FileHandle, BOOLEAN Echo)
BOOLEAN	DosCheckInput (VOID)
VOID	DosPrintCharacter (WORD FileHandle, CHAR Character)
BOOLEAN	DosBIOSInitialize (VOID)
BOOLEAN	DosControlBreak (VOID)
VOID	DosEchoCharacter (CHAR Character)
BOOLEAN	DosKRNLInitialize (VOID)

Variables
PBIOS_DATA	BiosData
PDOS_DATA	DosData
PDOS_SYSVARS	SysVars
PDOS_SDA	Sda
CALLBACK16	DosContext

Macro Definition Documentation

BIOS_CODE_SEGMENT

#define BIOS_CODE_SEGMENT   0x70

Definition at line 30 of file dos.h.

BIOS_DATA_SEGMENT

#define BIOS_DATA_SEGMENT   0x70

Definition at line 31 of file dos.h.

DOS_CHAR_ATTRIBUTE

#define DOS_CHAR_ATTRIBUTE   0x07

Definition at line 49 of file dos.h.

DOS_CODE_SEGMENT

#define DOS_CODE_SEGMENT   0x80

Definition at line 32 of file dos.h.

DOS_COMMAND_INTERPRETER

#define DOS_COMMAND_INTERPRETER   L"%SystemRoot%\\system32\\COMMAND.COM /k %SystemRoot%\\system32\\AUTOEXEC.NT"

Definition at line 28 of file dos.h.

DOS_CONFIG_PATH

#define DOS_CONFIG_PATH   L"%SystemRoot%\\system32\\CONFIG.NT"

Definition at line 27 of file dos.h.

DOS_DATA_OFFSET

#define DOS_DATA_OFFSET

(

x

)

FIELD_OFFSET(DOS_DATA, x)

Definition at line 35 of file dos.h.

DOS_DATA_SEGMENT

#define DOS_DATA_SEGMENT   0xA5

Definition at line 33 of file dos.h.

DOS_DIR_LENGTH

#define DOS_DIR_LENGTH   64

Definition at line 47 of file dos.h.

DOS_ERROR_HANDLE

#define DOS_ERROR_HANDLE   2

Definition at line 44 of file dos.h.

DOS_INPUT_HANDLE

#define DOS_INPUT_HANDLE   0

Definition at line 42 of file dos.h.

DOS_OUTPUT_HANDLE

#define DOS_OUTPUT_HANDLE   1

Definition at line 43 of file dos.h.

DOS_SFT_SIZE

#define DOS_SFT_SIZE   255

Definition at line 46 of file dos.h.

DOS_VERSION

#define DOS_VERSION   MAKEWORD(5, 00)

Definition at line 24 of file dos.h.

INVALID_DOS_HANDLE

#define INVALID_DOS_HANDLE   0xFFFF

Definition at line 41 of file dos.h.

NTDOS_VERSION

#define NTDOS_VERSION   MAKEWORD(5, 50)

Definition at line 25 of file dos.h.

NUM_DRIVES

#define NUM_DRIVES   ('Z' - 'A' + 1)

Definition at line 48 of file dos.h.

RegisterDosInt32

#define RegisterDosInt32	(		IntNumber,
			IntHandler
	)

Value:

do { \
    ASSERT((0x20 <= IntNumber) && (IntNumber <= 0x2F));     \
    RegisterInt32(DosContext.TrampolineFarPtr +             \
                  DosContext.TrampolineSize   +             \
                  (IntNumber - 0x20) * Int16To32StubSize,   \
                  (IntNumber), (IntHandler), NULL);         \
} while(0);

Definition at line 314 of file dos.h.

SYSTEM_ENV_BLOCK

#define SYSTEM_ENV_BLOCK   0x600

Definition at line 37 of file dos.h.

SYSTEM_PSP

#define SYSTEM_PSP   0x0008

Definition at line 39 of file dos.h.

Typedef Documentation

BIOS_DATA

typedef struct _BIOS_DATA BIOS_DATA

DOS_CLOCK_TRANSFER_RECORD

typedef struct _DOS_CLOCK_TRANSFER_RECORD DOS_CLOCK_TRANSFER_RECORD

DOS_DATA

typedef struct _DOS_DATA DOS_DATA

DOS_FCB

typedef struct _DOS_FCB DOS_FCB

DOS_FIND_FILE_BLOCK

typedef struct _DOS_FIND_FILE_BLOCK DOS_FIND_FILE_BLOCK

DOS_INPUT_BUFFER

typedef struct _DOS_INPUT_BUFFER DOS_INPUT_BUFFER

DOS_SDA

typedef struct _DOS_SDA DOS_SDA

DOS_SYSVARS

typedef struct _DOS_SYSVARS DOS_SYSVARS

PBIOS_DATA

typedef struct _BIOS_DATA * PBIOS_DATA

PDOS_CLOCK_TRANSFER_RECORD

typedef struct _DOS_CLOCK_TRANSFER_RECORD * PDOS_CLOCK_TRANSFER_RECORD

PDOS_DATA

typedef struct _DOS_DATA * PDOS_DATA

PDOS_FCB

typedef struct _DOS_FCB * PDOS_FCB

PDOS_FIND_FILE_BLOCK

typedef struct _DOS_FIND_FILE_BLOCK * PDOS_FIND_FILE_BLOCK

PDOS_INPUT_BUFFER

typedef struct _DOS_INPUT_BUFFER * PDOS_INPUT_BUFFER

PDOS_SDA

typedef struct _DOS_SDA * PDOS_SDA

PDOS_SYSVARS

typedef struct _DOS_SYSVARS * PDOS_SYSVARS

Function Documentation

C_ASSERT()

C_ASSERT

(

sizeof(BIOS_DATA)

= =0x100

)

ConDrvCleanup()

VOID ConDrvCleanup

(

VOID

)

Definition at line 147 of file condrv.c.

{
    if (Con) DosDeleteDevice(Con);
}

ConDrvInitialize()

VOID ConDrvInitialize

(

VOID

)

Definition at line 132 of file condrv.c.

{
    Con = DosCreateDevice(DOS_DEVATTR_STDIN
                          | DOS_DEVATTR_STDOUT
                          | DOS_DEVATTR_CON
                          | DOS_DEVATTR_CHARACTER,
                          "CON");
 
    Con->ReadRoutine        = ConDrvReadInput;
    Con->InputStatusRoutine = ConDrvInputStatus;
    Con->WriteRoutine       = ConDrvWriteOutput;
    Con->OpenRoutine        = ConDrvOpen;
    Con->CloseRoutine       = ConDrvClose;
}

Referenced by DosKRNLInitialize().

DosBIOSInitialize()

BOOLEAN DosBIOSInitialize

(

VOID

)

setBP(0x091E); // DOS base stack pointer relic value

Definition at line 221 of file bios.c.

{
    FILE *Stream;
    WCHAR Buffer[256];
 
    /* Set the data segment */
    setDS(BIOS_DATA_SEGMENT);
 
    /* Initialize the global DOS BIOS data area */
    BiosData = (PBIOS_DATA)SEG_OFF_TO_PTR(BIOS_DATA_SEGMENT, 0x0000);
 
    /* Initialize the DOS BIOS stack */
    // FIXME: Add a block of fixed size for the stack in BIOS/DOS_DATA instead!
    setSS(0x0F00);
    setSP(0x0FF0);
 
    /*
     * Initialize the INT 13h (BIOS Disk Services) handler chain support.
     *
     * The INT 13h handler chain is some functionality that allows DOS
     * to insert disk filter drivers in between the (hooked) INT 13h handler
     * and its original handler.
     * Typically, those are:
     * - filter for detecting disk changes (for floppy disks),
     * - filter for tracking formatting calls and correcting DMA boundary errors,
     * - a possible filter to work around a bug in a particular version of PC-AT's
     *   IBM's ROM BIOS (on systems with model byte FCh and BIOS date "01/10/84" only)
     * (see http://www.ctyme.com/intr/rb-4453.htm for more details).
     *
     * This functionality is known to be used by some legitimate programs,
     * by Windows 3.x, as well as some illegitimate ones (aka. virii).
     *
     * See extra information about this support in dos.h
     */
    // FIXME: Should be done by the DOS BIOS
    BiosData->RomBiosInt13 = ((PULONG)BaseAddress)[0x13];
    BiosData->PrevInt13    = BiosData->RomBiosInt13;
//  RegisterDosInt32(0x13, DosInt13h); // Unused at the moment!
 
    //
    // HERE: Do all hardware initialization needed for DOS
    //
 
    /*
     * SysInit part...
     */
 
    /* Initialize the DOS kernel (DosInit) */
    if (!DosKRNLInitialize())
    {
        BiosDisplayMessage("Failed to load the DOS kernel! Exiting...\n");
        return FALSE;
    }
 
    /* DOS kernel loading succeeded, we can finish the initialization */
 
    /* Build the system master (pre-) environment block (inherited by the shell) */
    if (!DosBuildSysEnvBlock())
    {
        DosDisplayMessage("An error occurred when setting up the system environment block.\n");
    }
 
    /* TODO: Read CONFIG.NT/SYS */
    Stream = _wfopen(DOS_CONFIG_PATH, L"r");
    if (Stream != NULL)
    {
        while (fgetws(Buffer, ARRAYSIZE(Buffer), Stream))
        {
            // TODO: Parse the line
        }
        fclose(Stream);
    }
 
    return TRUE;
}

Referenced by DosStart().

DosCheckInput()

BOOLEAN DosCheckInput

(

VOID

)

Definition at line 120 of file bios.c.

{
    PDOS_FILE_DESCRIPTOR Descriptor = DosGetHandleFileDescriptor(DOS_INPUT_HANDLE);
 
    if (Descriptor == NULL)
    {
        /* Invalid handle */
        Sda->LastErrorCode = ERROR_INVALID_HANDLE; // ERROR_FILE_NOT_FOUND
        return FALSE;
    }
 
    if (Descriptor->DeviceInfo & FILE_INFO_DEVICE)
    {
        WORD Result;
        PDOS_DEVICE_NODE Node = DosGetDriverNode(Descriptor->DevicePointer);
 
        if (!Node->InputStatusRoutine) return FALSE;
 
        Result = Node->InputStatusRoutine(Node);
        return !(Result & DOS_DEVSTAT_BUSY);
    }
    else
    {
        DWORD FileSizeHigh;
        DWORD FileSize = GetFileSize(Descriptor->Win32Handle, &FileSizeHigh);
        LONG LocationHigh = 0;
        DWORD Location = SetFilePointer(Descriptor->Win32Handle, 0, &LocationHigh, FILE_CURRENT);
 
        return ((Location != FileSize) || (LocationHigh != FileSizeHigh));
    }
}

Referenced by DosInt21h().

DosControlBreak()

BOOLEAN DosControlBreak

(

VOID

)

Definition at line 181 of file dos.c.

{
    setCF(0);
 
    /* Print an extra newline */
    DosPrintCharacter(DOS_OUTPUT_HANDLE, '\r');
    DosPrintCharacter(DOS_OUTPUT_HANDLE, '\n');
 
    /* Call interrupt 0x23 */
    Int32Call(&DosContext, 0x23);
 
    if (getCF())
    {
        DosTerminateProcess(Sda->CurrentPsp, 0, 0);
        return TRUE;
    }
 
    return FALSE;
}

Referenced by DosInt21h(), and DosReadLineBuffered().

DosEchoCharacter()

VOID DosEchoCharacter

(

CHAR

Character

)

Definition at line 48 of file bios.c.

{
    switch (Character)
    {
        case '\0':
        {
            /* Nothing */
            break;
        }
 
        case '\b':
        {
            /* Erase the character */
            DosPrintCharacter(DOS_OUTPUT_HANDLE, '\b');
            DosPrintCharacter(DOS_OUTPUT_HANDLE, ' ');
            DosPrintCharacter(DOS_OUTPUT_HANDLE, '\b');
            break;
        }
 
        default:
        {
            /*
             * Check if this is a special character
             * NOTE: \r and \n are handled by the underlying driver!
             */
            if (Character < 0x20 && Character != '\r' && Character != '\n')
            {
                DosPrintCharacter(DOS_OUTPUT_HANDLE, '^');
                Character += 'A' - 1;
            }
 
            /* Echo the character */
            DosPrintCharacter(DOS_OUTPUT_HANDLE, Character);
        }
    }
}

Referenced by DosReadCharacter(), DosReadFile(), and DosReadLineBuffered().

DosKRNLInitialize()

BOOLEAN DosKRNLInitialize

(

VOID

)

Definition at line 2264 of file dos.c.

{
    UCHAR i;
    PDOS_SFT Sft;
    LPSTR Path;
    BOOLEAN Success = TRUE;
    DWORD dwRet;
    CHAR CurrentDirectory[MAX_PATH];
    CHAR DosDirectory[DOS_DIR_LENGTH];
 
    static const BYTE NullDriverRoutine[] =
    {
        /* Strategy routine entry */
        0x26, // mov [Request.Status], DOS_DEVSTAT_DONE
        0xC7,
        0x47,
        FIELD_OFFSET(DOS_REQUEST_HEADER, Status),
        LOBYTE(DOS_DEVSTAT_DONE),
        HIBYTE(DOS_DEVSTAT_DONE),
 
        /* Interrupt routine entry */
        0xCB, // retf
    };
 
    /* Set the data segment */
    setDS(DOS_DATA_SEGMENT);
 
    /* Initialize the global DOS data area */
    DosData = (PDOS_DATA)SEG_OFF_TO_PTR(DOS_DATA_SEGMENT, 0x0000);
    RtlZeroMemory(DosData, sizeof(*DosData));
 
    /* Initialize the DOS stack */
    setSS(DOS_DATA_SEGMENT);
    setSP(DOS_DATA_OFFSET(DosStack) + sizeof(DosData->DosStack) - sizeof(WORD));
 
    /* Initialize the list of lists */
    SysVars = &DosData->SysVars;
    RtlZeroMemory(SysVars, sizeof(*SysVars));
    SysVars->FirstSft = MAKELONG(DOS_DATA_OFFSET(Sft), DOS_DATA_SEGMENT);
    SysVars->CurrentDirs = MAKELONG(DOS_DATA_OFFSET(CurrentDirectories),
                                    DOS_DATA_SEGMENT);
    /*
     * The last drive can be redefined with the LASTDRIVE command.
     * At the moment, set the real maximum possible, 'Z'.
     */
    SysVars->NumLocalDrives = 'Z' - 'A' + 1; // See #define NUM_DRIVES in dos.h
 
    /* The boot drive is initialized to the %SYSTEMDRIVE% value */
    // NOTE: Using the NtSystemRoot system variable might be OS-specific...
    SysVars->BootDrive = RtlUpcaseUnicodeChar(SharedUserData->NtSystemRoot[0]) - 'A' + 1;
 
    /* Initialize the NUL device driver */
    SysVars->NullDevice.Link = MAXDWORD;
    SysVars->NullDevice.DeviceAttributes = DOS_DEVATTR_NUL | DOS_DEVATTR_CHARACTER;
    // Offset from within the DOS data segment
    SysVars->NullDevice.StrategyRoutine  = DOS_DATA_OFFSET(NullDriverRoutine);
    // Hardcoded to the RETF inside StrategyRoutine
    SysVars->NullDevice.InterruptRoutine = SysVars->NullDevice.StrategyRoutine + 6;
    RtlFillMemory(SysVars->NullDevice.DeviceName,
                  sizeof(SysVars->NullDevice.DeviceName),
                  ' ');
    RtlCopyMemory(SysVars->NullDevice.DeviceName, "NUL", strlen("NUL"));
    RtlCopyMemory(DosData->NullDriverRoutine,
                  NullDriverRoutine,
                  sizeof(NullDriverRoutine));
 
    /* Default DOS version to report */
    DosData->DosVersion = DOS_VERSION;
 
    /* Initialize the swappable data area */
    Sda = &DosData->Sda;
    RtlZeroMemory(Sda, sizeof(*Sda));
 
    /* Get the current directory and convert it to a DOS path */
    dwRet = GetCurrentDirectoryA(sizeof(CurrentDirectory), CurrentDirectory);
    if (dwRet == 0)
    {
        Success = FALSE;
        DPRINT1("GetCurrentDirectoryA failed (Error: %u)\n", GetLastError());
    }
    else if (dwRet > sizeof(CurrentDirectory))
    {
        Success = FALSE;
        DPRINT1("Current directory too long (%d > MAX_PATH) for GetCurrentDirectoryA\n", dwRet);
    }
 
    if (Success)
    {
        dwRet = GetShortPathNameA(CurrentDirectory, DosDirectory, sizeof(DosDirectory));
        if (dwRet == 0)
        {
            Success = FALSE;
            DPRINT1("GetShortPathNameA failed (Error: %u)\n", GetLastError());
        }
        else if (dwRet > sizeof(DosDirectory))
        {
            Success = FALSE;
            DPRINT1("Short path too long (%d > DOS_DIR_LENGTH) for GetShortPathNameA\n", dwRet);
        }
    }
 
    if (!Success)
    {
        /* We failed, use the boot drive instead */
        DosDirectory[0] = SysVars->BootDrive + 'A' - 1;
        DosDirectory[1] = ':';
        DosDirectory[2] = '\\';
        DosDirectory[3] = '\0';
    }
 
    /* Set the current drive */
    Sda->CurrentDrive = RtlUpperChar(DosDirectory[0]) - 'A';
 
    /* Get the directory part of the path and set the current directory */
    Path = strchr(DosDirectory, '\\');
    if (Path != NULL)
    {
        Path++; // Skip the backslash
        strncpy(DosData->CurrentDirectories[Sda->CurrentDrive], Path, DOS_DIR_LENGTH);
    }
    else
    {
        DosData->CurrentDirectories[Sda->CurrentDrive][0] = '\0';
    }
 
    /* Set the current PSP to the system PSP */
    Sda->CurrentPsp = SYSTEM_PSP;
 
    /* Initialize the SFT */
    Sft = (PDOS_SFT)FAR_POINTER(SysVars->FirstSft);
    Sft->Link = MAXDWORD;
    Sft->NumDescriptors = DOS_SFT_SIZE;
 
    for (i = 0; i < Sft->NumDescriptors; i++)
    {
        /* Clear the file descriptor entry */
        RtlZeroMemory(&Sft->FileDescriptors[i], sizeof(DOS_FILE_DESCRIPTOR));
    }
 
    /* Initialize memory management */
    DosInitializeMemory();
 
    /* Initialize the callback context */
    InitializeContext(&DosContext, DOS_CODE_SEGMENT, 0x0000);
 
    /* Register the DOS 32-bit Interrupts */
    RegisterDosInt32(0x20, DosInt20h        );
    RegisterDosInt32(0x21, DosInt21h        );
//  RegisterDosInt32(0x22, DosInt22h        ); // Termination
    RegisterDosInt32(0x23, DosBreakInterrupt); // Ctrl-C / Ctrl-Break
//  RegisterDosInt32(0x24, DosInt24h        ); // Critical Error
    RegisterDosInt32(0x25, DosAbsoluteRead  ); // Absolute Disk Read
    RegisterDosInt32(0x26, DosAbsoluteWrite ); // Absolute Disk Write
    RegisterDosInt32(0x27, DosInt27h        ); // Terminate and Stay Resident
    RegisterDosInt32(0x28, DosIdle          ); // DOS Idle Interrupt
    RegisterDosInt32(0x29, DosFastConOut    ); // DOS 2+ Fast Console Output
    RegisterDosInt32(0x2F, DosInt2Fh        ); // Multiplex Interrupt
 
    /* Unimplemented DOS interrupts */
    RegisterDosInt32(0x2A, DosInt2Ah); // DOS Critical Sections / Network
//  RegisterDosInt32(0x2E, NULL); // COMMAND.COM "Reload Transient"
//  COMMAND.COM adds support for INT 2Fh, AX=AE00h and AE01h "Installable Command - Installation Check & Execute"
//  COMMAND.COM adds support for INT 2Fh, AX=5500h "COMMAND.COM Interface"
 
    /* Reserved DOS interrupts */
    RegisterDosInt32(0x2B, NULL);
    RegisterDosInt32(0x2C, NULL);
    RegisterDosInt32(0x2D, NULL);
 
    /* Initialize country data */
    DosCountryInitialize();
 
    /* Load the CON driver */
    ConDrvInitialize();
 
    /* Load the XMS driver (HIMEM) */
    XmsInitialize();
 
    /* Load the EMS driver */
    if (!EmsDrvInitialize(EMS_SEGMENT, EMS_TOTAL_PAGES))
    {
        DosDisplayMessage("Could not initialize EMS. EMS will not be available.\n"
                          "Page frame segment or number of EMS pages invalid.\n");
    }
 
    /* Finally initialize the UMBs */
    DosInitializeUmb();
 
    return TRUE;
}

Referenced by DosBIOSInitialize().

DosPrintCharacter()

VOID DosPrintCharacter	(	WORD	FileHandle,
		CHAR	Character
	)

Definition at line 152 of file bios.c.

{
    WORD BytesWritten;
 
    Sda->ByteBuffer = Character;
 
    /* Use the file writing function */
    DosWriteFile(FileHandle,
                 MAKELONG(DOS_DATA_OFFSET(Sda.ByteBuffer), DOS_DATA_SEGMENT),
                 1,
                 &BytesWritten);
}

Referenced by DosCharPrint(), DosControlBreak(), DosEchoCharacter(), and DosInt21h().

DosReadCharacter()

CHAR DosReadCharacter	(	WORD	FileHandle,
		BOOLEAN	Echo
	)

Definition at line 85 of file bios.c.

{
    WORD BytesRead;
    PDOS_FILE_DESCRIPTOR Descriptor = NULL;
    WORD OldDeviceInfo;
 
    /* Find the standard input descriptor and switch it to binary mode */
    Descriptor = DosGetHandleFileDescriptor(FileHandle);
    if (Descriptor)
    {
        OldDeviceInfo = Descriptor->DeviceInfo;
        Descriptor->DeviceInfo |= FILE_INFO_BINARY;
    }
 
    Sda->ByteBuffer = '\0';
    DPRINT("DosReadCharacter\n");
 
    /* Use the file reading function */
    DosReadFile(FileHandle,
                MAKELONG(DOS_DATA_OFFSET(Sda.ByteBuffer), DOS_DATA_SEGMENT),
                1,
                &BytesRead);
 
    /* Check if we should echo and the file is actually the CON device */
    if (Echo && Descriptor && Descriptor->DeviceInfo & FILE_INFO_DEVICE)
    {
        /* Echo the character */
        DosEchoCharacter(Sda->ByteBuffer);
    }
 
    /* Restore the old mode and return the character */
    if (Descriptor) Descriptor->DeviceInfo = OldDeviceInfo;
    return Sda->ByteBuffer;
}

Referenced by DosInt21h().

Variable Documentation

BiosData

PBIOS_DATA BiosData

extern

Definition at line 42 of file bios.c.

Referenced by DosBIOSInitialize(), DosInt2Fh(), PciScanBus(), and PPBridge_SaveCurrentSettings().

DosContext

CALLBACK16 DosContext

extern

Definition at line 40 of file dos.c.

Referenced by ConDrvInputStatus(), ConDrvReadInput(), ConDrvWriteOutput(), Dem_BiosCharPrint(), DosBootsectorInitialize(), DosCallDriver(), DosControlBreak(), DosFastConOut(), DosKRNLInitialize(), and DosStart().

DosData

PDOS_DATA DosData

extern

Definition at line 45 of file dos.c.

Referenced by demFileFindFirst(), DosChangeDirectory(), DosChangeDrive(), DosCreatePsp(), DosInt21h(), DosInt2Fh(), DosKRNLInitialize(), and DosReadFile().

Sda

PDOS_SDA Sda

extern

Definition at line 48 of file dos.c.

Referenced by CmdSetExitCode(), CmdStartProcess(), DosAllocateMemory(), DosCallDriver(), DosChangeDirectory(), DosChangeDrive(), DosCheckInput(), DosCloseHandle(), DosCombineFreeBlocks(), DosControlBreak(), DosCopyHandleTable(), DosCreateFile(), DosCreateFileEx(), DosCreatePsp(), DosDeviceIoControl(), DosDeviceIoControlDrive(), DosDuplicateHandle(), DosFlushFileBuffers(), DosForceDuplicateHandle(), DosFreeMemory(), DosGetPreviousUmb(), DosInitializeMemory(), DosInt21h(), DosIsFileOnCdRom(), DosKRNLInitialize(), DosLinkUmb(), DosLoadDriver(), DosLoadExecutableInternal(), DosLockFile(), DosOpenFile(), DosOpenHandle(), DosPrintCharacter(), DosQueryHandle(), DosReadCharacter(), DosReadFile(), DosReadLineBuffered(), DosResizeHandleTable(), DosResizeMemory(), DosSetProcessContext(), DosStartComSpec(), DosStartProcess32(), DosTerminateProcess(), DosUnlinkUmb(), and DosUnlockFile().

SysVars

PDOS_SYSVARS SysVars

extern

Definition at line 47 of file dos.c.

Referenced by DosAddDriver(), DosAllocateMemory(), DosChangeDirectory(), DosChangeDrive(), DosCopyHandleTable(), DosFindDeviceDescriptor(), DosFindFreeDescriptor(), DosFindWin32Descriptor(), DosGetDevice(), DosGetFileDescriptor(), DosGetPreviousUmb(), DosInitializeMemory(), DosInitializeUmb(), DosInt21h(), DosKRNLInitialize(), DosLinkUmb(), DosReadFile(), DosRemoveDriver(), DosTerminateProcess(), and DosUnlinkUmb().