/*++

Copyright (c) 1990  Microsoft Corporation

Module Name:

    cnvint.c

Abstract:

    Text to integer and integer to text converion routines.

Author:

    Steve Wood (stevewo) 23-Aug-1990

Revision History:

--*/

#include <ntrtlp.h>

#if defined(ALLOC_PRAGMA) && defined(NTOS_KERNEL_RUNTIME)
#pragma alloc_text(PAGE,RtlIntegerToChar)
#pragma alloc_text(PAGE,RtlCharToInteger)
#pragma alloc_text(PAGE,RtlUnicodeStringToInteger)
#pragma alloc_text(PAGE,RtlIntegerToUnicodeString)
#pragma alloc_text(PAGE,RtlLargeIntegerToChar)
#endif

CHAR RtlpIntegerChars[] = {'0', '1', '2', '3', '4', '5', '6', '7',
                           '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};

NTSTATUS
RtlIntegerToChar (
    IN ULONG Value,
    IN ULONG Base OPTIONAL,
    IN LONG OutputLength,
    OUT PSZ String
    )

/*++

Routine Description:

Arguments:

Return Value:

--*/

{
    CHAR Result[ 33 ], *s;
    ULONG Shift, Mask, Digit, Length;

    Shift = 0;
    switch( Base ) {
        case 16:    Shift = 4;  break;
        case  8:    Shift = 3;  break;
        case  2:    Shift = 1;  break;

        case  0:    Base = 10;
        case 10:    Shift = 0;  break;
        default:    return( STATUS_INVALID_PARAMETER );
        }

    if (Shift != 0) {
        Mask = 0xF >> 4 - Shift;
        }

    s = &Result[ 32 ];
    *s = '\0';
    do {
        if (Shift != 0) {
            Digit = Value & Mask;
            Value >>= Shift;
            }
        else {
            Digit = Value % Base;
            Value = Value / Base;
            }

        *--s = RtlpIntegerChars[ Digit ];
    } while (Value != 0);

    Length = &Result[ 32 ] - s;
    if (OutputLength < 0) {
        OutputLength = -OutputLength;
        while ((LONG)Length < OutputLength) {
            *--s = '0';
            Length++;
            }
        }

    if ((LONG)Length > OutputLength) {
        return( STATUS_BUFFER_OVERFLOW );
        }
    else {
        try {
            RtlMoveMemory( String, s, Length );

            if ((LONG)Length < OutputLength) {
                String[ Length ] = '\0';
                }
            }
        except( EXCEPTION_EXECUTE_HANDLER ) {
            return( GetExceptionCode() );
            }

        return( STATUS_SUCCESS );
        }
}


NTSTATUS
RtlCharToInteger (
    IN PCSZ String,
    IN ULONG Base OPTIONAL,
    OUT PULONG Value
    )
{
    CHAR c, Sign;
    ULONG Result, Digit, Shift;

    while ((Sign = *String++) <= ' ') {
        if (!*String) {
            String--;
            break;
            }
        }

    c = Sign;
    if (c == '-' || c == '+') {
        c = *String++;
        }

    if (!ARGUMENT_PRESENT( Base )) {
        Base = 10;
        Shift = 0;
        if (c == '0') {
            c = *String++;
            if (c == 'x') {
                Base = 16;
                Shift = 4;
                }
            else
            if (c == 'o') {
                Base = 8;
                Shift = 3;
                }
            else
            if (c == 'b') {
                Base = 2;
                Shift = 1;
                }
            else {
                String--;
                }

            c = *String++;
            }
        }
    else {
        switch( Base ) {
            case 16:    Shift = 4;  break;
            case  8:    Shift = 3;  break;
            case  2:    Shift = 1;  break;
            case 10:    Shift = 0;  break;
            default:    return( STATUS_INVALID_PARAMETER );
            }
        }

    Result = 0;
    while (c) {
        if (c >= '0' && c <= '9') {
            Digit = c - '0';
            }
        else
        if (c >= 'A' && c <= 'F') {
            Digit = c - 'A' + 10;
            }
        else
        if (c >= 'a' && c <= 'f') {
            Digit = c - 'a' + 10;
            }
        else {
            break;
            }

        if (Digit >= Base) {
            break;
            }

        if (Shift == 0) {
            Result = (Base * Result) + Digit;
            }
        else {
            Result = (Result << Shift) | Digit;
            }

        c = *String++;
        }

    if (Sign == '-') {
        Result = (ULONG)(-(LONG)Result);
        }

    try {
        *Value = Result;
        }
    except( EXCEPTION_EXECUTE_HANDLER ) {
        return( GetExceptionCode() );
        }

    return( STATUS_SUCCESS );
}


NTSTATUS
RtlUnicodeStringToInteger (
    IN PUNICODE_STRING String,
    IN ULONG Base OPTIONAL,
    OUT PULONG Value
    )
{
    PCWSTR s;
    WCHAR c, Sign;
    ULONG nChars, Result, Digit, Shift;

    s = String->Buffer;
    nChars = String->Length / sizeof( WCHAR );
    while (nChars-- && (Sign = *s++) <= ' ') {
        if (!nChars) {
            Sign = UNICODE_NULL;
            break;
            }
        }

    c = Sign;
    if (c == L'-' || c == L'+') {
        if (nChars) {
            nChars--;
            c = *s++;
            }
        else {
            c = UNICODE_NULL;
            }
        }

    if (!ARGUMENT_PRESENT( Base )) {
        Base = 10;
        Shift = 0;
        if (c == L'0') {
            if (nChars) {
                nChars--;
                c = *s++;
                if (c == L'x') {
                    Base = 16;
                    Shift = 4;
                    }
                else
                if (c == L'o') {
                    Base = 8;
                    Shift = 3;
                    }
                else
                if (c == L'b') {
                    Base = 2;
                    Shift = 1;
                    }
                else {
                    nChars++;
                    s--;
                    }
                }

            if (nChars) {
                nChars--;
                c = *s++;
                }
            else {
                c = UNICODE_NULL;
                }
            }
        }
    else {
        switch( Base ) {
            case 16:    Shift = 4;  break;
            case  8:    Shift = 3;  break;
            case  2:    Shift = 1;  break;
            case 10:    Shift = 0;  break;
            default:    return( STATUS_INVALID_PARAMETER );
            }
        }

    Result = 0;
    while (c != UNICODE_NULL) {
        if (c >= L'0' && c <= L'9') {
            Digit = c - L'0';
            }
        else
        if (c >= L'A' && c <= L'F') {
            Digit = c - L'A' + 10;
            }
        else
        if (c >= L'a' && c <= L'f') {
            Digit = c - L'a' + 10;
            }
        else {
            break;
            }

        if (Digit >= Base) {
            break;
            }

        if (Shift == 0) {
            Result = (Base * Result) + Digit;
            }
        else {
            Result = (Result << Shift) | Digit;
            }

        if (!nChars) {
            break;
            }
        nChars--;
        c = *s++;
        }

    if (Sign == L'-') {
        Result = (ULONG)(-(LONG)Result);
        }

    try {
        *Value = Result;
        }
    except( EXCEPTION_EXECUTE_HANDLER ) {
        return( GetExceptionCode() );
        }

    return( STATUS_SUCCESS );
}


NTSTATUS
RtlIntegerToUnicodeString (
    IN ULONG Value,
    IN ULONG Base OPTIONAL,
    IN OUT PUNICODE_STRING String
    )
{
    NTSTATUS Status;
    UCHAR ResultBuffer[ 16 ];
    ANSI_STRING AnsiString;

    Status = RtlIntegerToChar( Value, Base, sizeof( ResultBuffer ), ResultBuffer );
    if (NT_SUCCESS( Status )) {
        AnsiString.Buffer = ResultBuffer;
        AnsiString.MaximumLength = sizeof( ResultBuffer );
        AnsiString.Length = (USHORT)strlen( ResultBuffer );
        Status = RtlAnsiStringToUnicodeString( String, &AnsiString, FALSE );
        }

    return( Status );
}


NTSTATUS
RtlLargeIntegerToChar (
    IN PLARGE_INTEGER Value,
    IN ULONG Base OPTIONAL,
    IN LONG OutputLength,
    OUT PSZ String
    )

/*++

Routine Description:

Arguments:

Return Value:

--*/

{
    CHAR Result[ 100 ], *s;
    ULONG Shift, Mask, Digit, Length;

    Shift = 0;
    switch( Base ) {
        case 16:    Shift = 4;  break;
        case  8:    Shift = 3;  break;
        case  2:    Shift = 1;  break;

        case  0:
        case 10:    Shift = 0;  break;
        default:    return( STATUS_INVALID_PARAMETER );
        }

    if (Shift != 0) {
        Mask = 0xF >> 4 - Shift;
        }

    s = &Result[ 99 ];
    *s = '\0';
    if (Shift != 0) {
        ULONG LowValue,HighValue,HighShift,HighMask;

        LowValue = Value->LowPart;
        HighValue = Value->HighPart;
        HighShift = Shift - (sizeof(ULONG) % Shift);
        HighMask = 0xF >> 4 - HighShift;
        do {
            Digit = LowValue & Mask;
            LowValue = (LowValue >> Shift) | ((HighValue & HighMask) << (sizeof(ULONG) - HighShift));
            HighValue = HighValue >> HighShift;
            *--s = RtlpIntegerChars[ Digit ];
        } while ((LowValue | HighValue) != 0);
    } else {
        LARGE_INTEGER TempValue=*Value;
        do {
            TempValue = RtlExtendedLargeIntegerDivide(TempValue,Base,&Digit);
            *--s = RtlpIntegerChars[ Digit ];
        } while (TempValue.HighPart != 0 || TempValue.LowPart != 0);
    }

    Length = &Result[ 99 ] - s;
    if (OutputLength < 0) {
        OutputLength = -OutputLength;
        while ((LONG)Length < OutputLength) {
            *--s = '0';
            Length++;
            }
        }

    if ((LONG)Length > OutputLength) {
        return( STATUS_BUFFER_OVERFLOW );
        }
    else {
        try {
            RtlMoveMemory( String, s, Length );

            if ((LONG)Length < OutputLength) {
                String[ Length ] = '\0';
                }
            }
        except( EXCEPTION_EXECUTE_HANDLER ) {
            return( GetExceptionCode() );
            }

        return( STATUS_SUCCESS );
        }
}