gecko-dev/layout/generic/nsIntervalSet.cpp

77 строки
2.3 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
// vim:cindent:ts=8:et:sw=4:
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/* a set of ranges on a number-line */
#include "nsIntervalSet.h"
#include <new>
#include <algorithm>
#include "nsIPresShell.h" // for allocation
using namespace mozilla;
nsIntervalSet::nsIntervalSet(nsIPresShell *aPresShell)
: mList(nullptr), mPresShell(aPresShell) {}
nsIntervalSet::~nsIntervalSet() {
Interval *current = mList;
while (current) {
Interval *trash = current;
current = current->mNext;
FreeInterval(trash);
}
}
void *nsIntervalSet::AllocateInterval() {
return mPresShell->AllocateByObjectID(eArenaObjectID_nsIntervalSet_Interval,
sizeof(Interval));
}
void nsIntervalSet::FreeInterval(nsIntervalSet::Interval *aInterval) {
NS_ASSERTION(aInterval, "null interval");
aInterval->Interval::~Interval();
mPresShell->FreeByObjectID(eArenaObjectID_nsIntervalSet_Interval, aInterval);
}
void nsIntervalSet::IncludeInterval(coord_type aBegin, coord_type aEnd) {
auto newInterval = static_cast<Interval *>(AllocateInterval());
new (newInterval) Interval(aBegin, aEnd);
Interval **current = &mList;
while (*current && (*current)->mEnd < aBegin) current = &(*current)->mNext;
newInterval->mNext = *current;
*current = newInterval;
Interval *subsumed = newInterval->mNext;
while (subsumed && subsumed->mBegin <= aEnd) {
newInterval->mBegin = std::min(newInterval->mBegin, subsumed->mBegin);
newInterval->mEnd = std::max(newInterval->mEnd, subsumed->mEnd);
newInterval->mNext = subsumed->mNext;
FreeInterval(subsumed);
subsumed = newInterval->mNext;
}
}
bool nsIntervalSet::Intersects(coord_type aBegin, coord_type aEnd) const {
Interval *current = mList;
while (current && current->mBegin <= aEnd) {
if (current->mEnd >= aBegin) return true;
current = current->mNext;
}
return false;
}
bool nsIntervalSet::Contains(coord_type aBegin, coord_type aEnd) const {
Interval *current = mList;
while (current && current->mBegin <= aBegin) {
if (current->mEnd >= aEnd) return true;
current = current->mNext;
}
return false;
}