windows-xp/Source/XPSP1/NT/base/fs/utils/ifsutil/src/numset.cxx

#include <pch.cxx>

#define _NTAPI_ULIB_
#define _IFSUTIL_MEMBER_

#include "ulib.hxx"
#include "ifsutil.hxx"

#include "numset.hxx"
#include "iterator.hxx"

DEFINE_EXPORTED_CONSTRUCTOR( NUMBER_SET, OBJECT, IFSUTIL_EXPORT );

DEFINE_CONSTRUCTOR( NUMBER_EXTENT, OBJECT );

VOID
NUMBER_SET::Construct (
        )
/*++

Routine Description:

    Constructor for NUMBER_SET.

Arguments:

    None.

Return Value:

    None.

--*/
{
    _card = 0;
    _iterator = NULL;
}


VOID
NUMBER_SET::Destroy(
    )
/*++

Routine Description:

    This routine returns the NUMBER_SET to its initial state.

Arguments:

    None.

Return Value:

    None.

--*/
{
    _list.DeleteAllMembers();
    _card = 0;
    DELETE(_iterator);
}


IFSUTIL_EXPORT
NUMBER_SET::~NUMBER_SET(
    )
/*++

Routine Description:

    Destructor for NUMBER_SET.

Arguments:

    None.

Return Value:

    None.

--*/
{
    Destroy();
}


IFSUTIL_EXPORT
BOOLEAN
NUMBER_SET::Initialize(
    )
/*++

Routine Description:

    This routine initializes the stack for new input.

Arguments:

    None.

Return Value:

    FALSE   - Failure.
    TRUE    - Success.

--*/
{
    Destroy();

    if (!_list.Initialize() ||
        !(_iterator = _list.QueryIterator())) {

        Destroy();
        return FALSE;
    }

    return TRUE;
}

IFSUTIL_EXPORT
BOOLEAN
NUMBER_SET::Add(
    IN  BIG_INT Number
    )
/*++

Routine Description:

    This routine adds 'Number' to the set.

Arguments:

    Number  - Supplies the number to add to the set.

Return Value:

    FALSE   - Failure.
    TRUE    - Success.

--*/
{
    PNUMBER_EXTENT  p, pn;
    PNUMBER_EXTENT  new_extent;
    BIG_INT         next;

    DebugAssert(_iterator);

    _iterator->Reset();
    while (p = (PNUMBER_EXTENT) _iterator->GetPrevious()) {
        if (p->Start <= Number) {
            break;
        }
    }

    if (p) {

        next = p->Start + p->Length;

        if (Number < next) {
            return TRUE;
        }

        if (Number == next) {

            p->Length += 1;
            _card += 1;

            if (pn = (PNUMBER_EXTENT) _iterator->GetNext()) {

                if (pn->Start == Number + 1) {

                    p->Length += pn->Length;
                    pn = (PNUMBER_EXTENT) _list.Remove(_iterator);
                    DELETE(pn);
                }
            }

            return TRUE;
        }
    }

    if (p = (PNUMBER_EXTENT) _iterator->GetNext()) {

        if (Number + 1 == p->Start) {

            p->Start = Number;
            p->Length += 1;
            _card += 1;
            return TRUE;
        }
    }

    if (!(new_extent = NEW NUMBER_EXTENT)) {
        return FALSE;
    }

    new_extent->Start = Number;
    new_extent->Length = 1;

    if (!_list.Insert(new_extent, _iterator)) {
        DELETE(new_extent);
        return FALSE;
    }

    _card += 1;

    return TRUE;
}

IFSUTIL_EXPORT
BOOLEAN
NUMBER_SET::AddStart(
    IN  BIG_INT Number
    )
/*++

Routine Description:

    This routine adds 'Number' to the set.  Call this routine once before calling 
    AddNext.

    NOTE: Do not insert other calls of this class in between AddStart and AddNext.

Arguments:

    Number    - Supplies the number to add to the set.

Return Value:

    FALSE   - Failure.
    TRUE    - Success.

--*/
{
    PNUMBER_EXTENT  p, pn;
    PNUMBER_EXTENT  new_extent;
    BIG_INT         next;

    DebugAssert(_iterator);

    _iterator->Reset();
    p = (PNUMBER_EXTENT) _iterator->GetPrevious();

    while (p != NULL) {
        if (p->Start <= Number) {
            next = p->Start + p->Length;

            // if within range, then done
            if (Number < next)
                return TRUE;

            // if passed the range by 1, try to expand the range to include it
            if (Number == next) {
                p->Length += 1;
                _card += 1;
                // see if the next range can be merged with the expanded range
                if (pn = (PNUMBER_EXTENT) _iterator->GetNext()) {
                   if (pn->Start == Number + 1) {
                       p->Length += pn->Length;
                       pn = (PNUMBER_EXTENT) _list.Remove(_iterator);
                       DELETE(pn);
                   }
                }
                p = (PNUMBER_EXTENT)_iterator->GetPrevious();
                return TRUE;
            }

            // if less than the next range by 1, try to expand the range to
            // include it.  There won't be a merge as there must be more than
            // one hole in between the two ranges
            if (p = (PNUMBER_EXTENT) _iterator->GetNext()) {
                if (p->Start <= Number)
                    continue;
                if ((Number+1) == p->Start) {
                    p->Start = Number;
                    p->Length += 1;
                    _card += 1;
                    return TRUE;
                }
            }
            break;
        } else {
            // search backwards
            p = (PNUMBER_EXTENT) _iterator->GetPrevious();
            if (p == NULL) {
                p = (PNUMBER_EXTENT) _iterator->GetNext();
                DebugAssert(p);
                if (p && ((Number+1) == p->Start)) {
                    p->Start = Number;
                    p->Length += 1;
                    _card += 1;
                    return TRUE;
                }
                break;
            }
        }
    }

    if (!(new_extent = NEW NUMBER_EXTENT)) {
        return FALSE;
    }

    new_extent->Start = Number;
    new_extent->Length = 1;

    if (!_list.Insert(new_extent, _iterator)) {
        DELETE(new_extent);
        return FALSE;
    }

    _card += 1;

    p = (PNUMBER_EXTENT) _iterator->GetPrevious();

    return TRUE;
}


IFSUTIL_EXPORT
BOOLEAN
NUMBER_SET::AddNext(
    IN  BIG_INT Number
    )
/*++

Routine Description:

    This routine adds 'Number' to the set.  Call this routine after calling
    AddStart once.  This routine differs from Add ni the sense that it searches
    through each of the subset from where it last added instead of starting
    backwards like Add does.

    NOTE: Do not insert any other call of this class in between two AddNext calls.

Arguments:

    Number    - Supplies the number to add to the set.

Return Value:

    FALSE   - Failure.
    TRUE    - Success.

--*/
{
    PNUMBER_EXTENT  p, pn;
    PNUMBER_EXTENT  new_extent;
    BIG_INT         next;

    DebugAssert(_iterator);

    if (!(p = (PNUMBER_EXTENT) _iterator->GetCurrent())) {
        _iterator->Reset();
        p = (PNUMBER_EXTENT) _iterator->GetPrevious();
    }

    while (p != NULL) {
        if (p->Start <= Number) {
            next = p->Start + p->Length;

            // if within range, then done
            if (Number < next)
                return TRUE;

            // if passed the range by 1, try to expand the range to include it
            if (Number == next) {
                p->Length += 1;
                _card += 1;
                // see if the next range can be merged with the expanded range
                if (pn = (PNUMBER_EXTENT) _iterator->GetNext()) {
                   if (pn->Start == Number + 1) {
                       p->Length += pn->Length;
                       pn = (PNUMBER_EXTENT) _list.Remove(_iterator);
                       DELETE(pn);
                   }
                }
                p = (PNUMBER_EXTENT)_iterator->GetPrevious();
                return TRUE;
            }

            // if less than the next range by 1, try to expand the range to
            // include it.  There won't be a merge as there must be more than
            // one hole in between the two ranges
            if (p = (PNUMBER_EXTENT) _iterator->GetNext()) {
                if (p->Start <= Number)
                    continue;
                if ((Number+1) == p->Start) {
                    p->Start = Number;
                    p->Length += 1;
                    _card += 1;
                    return TRUE;
                }
            }
            break;
        } else {
            // search backwards
            p = (PNUMBER_EXTENT) _iterator->GetPrevious();
            if (p == NULL) {
                p = (PNUMBER_EXTENT) _iterator->GetNext();
                DebugAssert(p);
                if (p && ((Number+1) == p->Start)) {
                    p->Start = Number;
                    p->Length += 1;
                    _card += 1;
                    return TRUE;
                }
                break;
            }
        }
    }

    if (!(new_extent = NEW NUMBER_EXTENT)) {
        return FALSE;
    }

    new_extent->Start = Number;
    new_extent->Length = 1;

    if (!_list.Insert(new_extent, _iterator)) {
        DELETE(new_extent);
        return FALSE;
    }

    _card += 1;

    p = (PNUMBER_EXTENT) _iterator->GetPrevious();

    return TRUE;
}


IFSUTIL_EXPORT
BOOLEAN
NUMBER_SET::Add(
    IN  BIG_INT Start,
    IN  BIG_INT Length
    )
/*++

Routine Description:

    This routine adds the range of numbers to the set.

Arguments:

    Start   - Supplies the first number to add to the set.
    Length  - Supplies the length of the run to add.

Return Value:

    FALSE   - Failure.
    TRUE    - Success.

--*/
{
    BIG_INT i, sup;
    BOOLEAN r;

    sup = Start + Length;

    r = TRUE;
    for (i = Start; i < sup; i += 1) {
        r = Add(i) && r;
    }

    return r;
}


IFSUTIL_EXPORT
BOOLEAN
NUMBER_SET::Add(
    IN  PCNUMBER_SET    NumberSet
    )
/*++

Routine Description:

    This routine adds all of the elements in the given number set to
    this one.

Arguments:

    NumberSet   - Supplies the numbers to add.

Return Value:

    FALSE   - Failure.
    TRUE    - Success.

--*/
{
    ULONG   i, n;
    BIG_INT s, l;

    n = NumberSet->QueryNumDisjointRanges();

    for (i = 0; i < n; i++) {

        NumberSet->QueryDisjointRange(i, &s, &l);

        if (!Add(s, l)) {
            return FALSE;
        }
    }

    return TRUE;
}

IFSUTIL_EXPORT
BOOLEAN
NUMBER_SET::CheckAndAdd(
    IN  BIG_INT   Number,
    OUT PBOOLEAN  Duplicate
    )
/*++

Routine Description:

    This routine adds 'Number' to the set.

Arguments:

    Number  - Supplies the number to add to the set.

Return Value:

    FALSE   - Failure.
    TRUE    - Success.

--*/
{
    PNUMBER_EXTENT  p, pn;
    PNUMBER_EXTENT  new_extent;
    BIG_INT         next;

    DebugAssert(_iterator);
    DebugAssert(Duplicate);

    *Duplicate = FALSE;

    _iterator->Reset();
    while (p = (PNUMBER_EXTENT) _iterator->GetPrevious()) {
        if (p->Start <= Number) {
            break;
        }
    }

    if (p) {

        next = p->Start + p->Length;

        if (Number < next) {
            *Duplicate = TRUE;
            return TRUE;
        }

        if (Number == next) {

            p->Length += 1;
            _card += 1;

            if (pn = (PNUMBER_EXTENT) _iterator->GetNext()) {

                if (pn->Start == Number + 1) {

                    p->Length += pn->Length;
                    pn = (PNUMBER_EXTENT) _list.Remove(_iterator);
                    DELETE(pn);
                }
            }

            return TRUE;
        }
    }

    if (p = (PNUMBER_EXTENT) _iterator->GetNext()) {

        if (Number + 1 == p->Start) {

            p->Start = Number;
            p->Length += 1;
            _card += 1;
            return TRUE;
        }
    }

    if (!(new_extent = NEW NUMBER_EXTENT)) {
        return FALSE;
    }

    new_extent->Start = Number;
    new_extent->Length = 1;

    if (!_list.Insert(new_extent, _iterator)) {
        DELETE(new_extent);
        return FALSE;
    }

    _card += 1;

    return TRUE;
}

IFSUTIL_EXPORT
BOOLEAN
NUMBER_SET::Remove(
    IN  BIG_INT     Number
    )
/*++

Routine Description:

    This routine removes a number from the number set.

Arguments:

    Number  - Supplies the number to remove.

Routine Description:

    FALSE   - Failure.
    TRUE    - Success.

--*/
{
    PNUMBER_EXTENT  p;
    PNUMBER_EXTENT  new_extent;
    BIG_INT         next, new_length;

    DebugAssert(_iterator);

    _iterator->Reset();
    while (p = (PNUMBER_EXTENT) _iterator->GetNext()) {
        if (p->Start > Number) {
            break;
        }
    }

    if (p = (PNUMBER_EXTENT) _iterator->GetPrevious()) {

        next = p->Start + p->Length;

        if (p->Start == Number) {
            p->Start += 1;
            p->Length -= 1;
            _card -= 1;

            if (p->Length == 0) {
                p = (PNUMBER_EXTENT) _list.Remove(_iterator);
                DELETE(p);
            }

            return TRUE;
        }

        if (Number + 1 == next) {
            p->Length -= 1;
            _card -= 1;
            return TRUE;
        }

        if (Number < next) {

            if (!(new_extent = NEW NUMBER_EXTENT)) {
                return FALSE;
            }

            _iterator->GetNext();

            if (!_list.Insert(new_extent, _iterator)) {
                DELETE(new_extent);
                return FALSE;
            }

            new_length = Number - p->Start;

            new_extent->Start = Number + 1;
            new_extent->Length = p->Length - 1 - new_length;

            p->Length = new_length;

            _card -= 1;
        }
    }

    return TRUE;
}

IFSUTIL_EXPORT
BOOLEAN
NUMBER_SET::RemoveAll(
     )
{
    PNUMBER_EXTENT  p;

    DebugAssert(_iterator);

    _iterator->Reset();
    if ((p = (PNUMBER_EXTENT) _iterator->GetNext())) 
        do {
            p = (PNUMBER_EXTENT) _list.Remove(_iterator);
            DELETE(p);
        } while ((p=(PNUMBER_EXTENT)_iterator->GetCurrent()));
    _card = 0;
    return TRUE;
}

IFSUTIL_EXPORT
BOOLEAN
NUMBER_SET::CheckAndRemove(
    IN  BIG_INT     Number,
     OUT PBOOLEAN   DoesExists
    )
/*++

Routine Description:

    This routine removes a number from the number set.

Arguments:

    Number      - Supplies the number to remove.
     DoesExists - TRUE if Number was found in the set

Routine Description:

    FALSE   - Failure.
    TRUE    - Success.

--*/
{
    PNUMBER_EXTENT  p;
    PNUMBER_EXTENT  new_extent;
    BIG_INT         next, new_length;

    DebugAssert(_iterator);
    DebugAssert(DoesExists);

    *DoesExists = FALSE;

    _iterator->Reset();
    while (p = (PNUMBER_EXTENT) _iterator->GetNext()) {
        if (p->Start > Number) {
            break;
        }
    }

    if (p = (PNUMBER_EXTENT) _iterator->GetPrevious()) {

        next = p->Start + p->Length;

        if (p->Start == Number) {
            p->Start += 1;
            p->Length -= 1;
            _card -= 1;
            *DoesExists = TRUE;

            if (p->Length == 0) {
                p = (PNUMBER_EXTENT) _list.Remove(_iterator);
                DELETE(p);
            }

            return TRUE;
        }

        if (Number + 1 == next) {
            p->Length -= 1;
            _card -= 1;
            *DoesExists = TRUE;
            return TRUE;
        }

        if (Number < next) {

            if (!(new_extent = NEW NUMBER_EXTENT)) {
                return FALSE;
            }

            _iterator->GetNext();

            if (!_list.Insert(new_extent, _iterator)) {
                DELETE(new_extent);
                return FALSE;
            }

            new_length = Number - p->Start;

            new_extent->Start = Number + 1;
            new_extent->Length = p->Length - 1 - new_length;

            p->Length = new_length;

            _card -= 1;
            *DoesExists = TRUE;
        }
    }

    return TRUE;
}


IFSUTIL_EXPORT
BOOLEAN
NUMBER_SET::Remove(
    IN  BIG_INT Start,
    IN  BIG_INT Length
    )
/*++

Routine Description:

    This routine removes the given range from the number set.

Arguments:

    Start   - Supplies the beginning of the range.
    Length  - Supplies the length of the range.

Routine Description:

    FALSE   - Failure.
    TRUE    - Success.

--*/
{
    BIG_INT i, sup;
    BOOLEAN r;

    sup = Start + Length;

    r = TRUE;
    for (i = Start; i < sup; i += 1) {
        r = Remove(i) && r;
    }

    return r;
}


IFSUTIL_EXPORT
BOOLEAN
NUMBER_SET::Remove(
    IN  PCNUMBER_SET    NumberSet
    )
/*++

Routine Description:

    This routine removes all of the elements in the given number set from
    this one.

Arguments:

    NumberSet   - Supplies the numbers to remove.

Return Value:

    FALSE   - Failure.
    TRUE    - Success.

--*/
{
    ULONG   i, n;
    BIG_INT s, l;

    n = NumberSet->QueryNumDisjointRanges();
    for (i = 0; i < n; i++) {

        NumberSet->QueryDisjointRange(i, &s, &l);

        if (!Remove(s, l)) {
            return FALSE;
        }
    }

    return TRUE;
}


IFSUTIL_EXPORT
BIG_INT
NUMBER_SET::QueryNumber(
    IN  BIG_INT Index
    ) CONST
/*++

Routine Description:

    This routine returns the Nth number contained in this set.

Arguments:

    Index   - Supplies a zero-based index into the ordered set.

Return Value:

    The Nth number in this set.

--*/
{
    PNUMBER_EXTENT  p;
    BIG_INT         r;
    BIG_INT         count;

    DebugAssert(Index < _card);

    _iterator->Reset();
    count = 0;
    while (p = (PNUMBER_EXTENT) _iterator->GetNext()) {

        count += p->Length;

        if (count > Index) {
            break;
        }
    }

    DebugAssert(p);

    return p->Start + Index - (count - p->Length);
}


IFSUTIL_EXPORT
BOOLEAN
NUMBER_SET::DoesIntersectSet(
    IN  BIG_INT Start,
    IN  BIG_INT Length
    ) CONST
/*++

Routine Description:

    This routine computes whether or not the range specified intersects
    the current number set.  This routine will return FALSE if the
    intersection is empty, TRUE otherwise.

Arguments:

    Start   - Supplies the start of the range.
    Length  - Supplies the length of the range.

Return Value:

    FALSE   - The specified range does not intersect the number set.
    TRUE    - The specified range makes a non-empty intersection with
                the number set.

--*/
{
    PNUMBER_EXTENT  p;
    BIG_INT         pnext, next;

    DebugAssert(_iterator);

    if (Length == 0) {
        return FALSE;
    }

    next = Start + Length;

    _iterator->Reset();
    while (p = (PNUMBER_EXTENT) _iterator->GetNext()) {

        pnext = p->Start + p->Length;

        if (Start >= p->Start) {

            if (Start < pnext) {
                return TRUE;
            }
        } else {

            if (next > p->Start) {
                return TRUE;
            }
        }
    }

    return FALSE;
}


IFSUTIL_EXPORT
VOID
NUMBER_SET::QueryDisjointRange(
    IN  ULONG       Index,
    OUT PBIG_INT    Start,
    OUT PBIG_INT    Length
    ) CONST
/*++

Routine Description:

    This routine returns the 'Index'th disjoint range.  (This is zero
    based).

Arguments:

    Index   - Supplies the index of the disjoint range.
    Start   - Returns the start of the disjoint range.
    Length  - Returns the length of the disjoint range.

Return Value:

    None.

--*/
{
    ULONG           i;
    PNUMBER_EXTENT  p;

    DebugAssert(_iterator);

    _iterator->Reset();
    for (i = 0; i <= Index; i++) {
        p = (PNUMBER_EXTENT) _iterator->GetNext();
    }

    DebugAssert(p);
    DebugAssert(Start);
    DebugAssert(Length);

    *Start = p->Start;
    *Length = p->Length;
}


IFSUTIL_EXPORT
BOOLEAN
NUMBER_SET::QueryContainingRange(
    IN  BIG_INT     Number,
    OUT PBIG_INT    Start,
    OUT PBIG_INT    Length
    ) CONST
/*++

Routine Description:

    This routine returns the range that contains the given number.

Arguments:

    Number  - Supplies the number.
    Start   - Returns the start of the range.
    Length  - Returns the length of the range.

Return Value:

    FALSE   - The given number was not in the set.
    TRUE    - Success.

--*/
{
    PNUMBER_EXTENT  p;

    DebugAssert(_iterator);

    _iterator->Reset();
    while (p = (PNUMBER_EXTENT) _iterator->GetPrevious()) {
        if (p->Start <= Number) {
            break;
        }
    }

    if (!p || Number >= p->Start + p->Length) {
        return FALSE;
    }

    *Start = p->Start;
    *Length = p->Length;

    return TRUE;
}