summaryrefslogtreecommitdiffstats
path: root/src/corelib/tools/qringbuffer.cpp
diff options
context:
space:
mode:
Diffstat (limited to 'src/corelib/tools/qringbuffer.cpp')
-rw-r--r--src/corelib/tools/qringbuffer.cpp146
1 files changed, 98 insertions, 48 deletions
diff --git a/src/corelib/tools/qringbuffer.cpp b/src/corelib/tools/qringbuffer.cpp
index 85cfdaf129..4a2dfdec2b 100644
--- a/src/corelib/tools/qringbuffer.cpp
+++ b/src/corelib/tools/qringbuffer.cpp
@@ -1,32 +1,38 @@
/****************************************************************************
**
-** Copyright (C) 2015 The Qt Company Ltd.
+** Copyright (C) 2016 The Qt Company Ltd.
** Copyright (C) 2015 Alex Trotsenko <alex1973tr@gmail.com>
-** Contact: http://www.qt.io/licensing/
+** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtCore module of the Qt Toolkit.
**
-** $QT_BEGIN_LICENSE:LGPL21$
+** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
-** and conditions see http://www.qt.io/terms-conditions. For further
-** information use the contact form at http://www.qt.io/contact-us.
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
-** General Public License version 2.1 or version 3 as published by the Free
-** Software Foundation and appearing in the file LICENSE.LGPLv21 and
-** LICENSE.LGPLv3 included in the packaging of this file. Please review the
-** following information to ensure the GNU Lesser General Public License
-** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
-** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
**
-** As a special exception, The Qt Company gives you certain additional
-** rights. These rights are described in The Qt Company LGPL Exception
-** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
**
** $QT_END_LICENSE$
**
@@ -65,15 +71,17 @@ const char *QRingBuffer::readPointerAtPosition(qint64 pos, qint64 &length) const
void QRingBuffer::free(qint64 bytes)
{
+ Q_ASSERT(bytes <= bufferSize);
+
while (bytes > 0) {
- const qint64 blockSize = buffers.first().size() - head;
+ const qint64 blockSize = buffers.constFirst().size() - head;
if (tailBuffer == 0 || blockSize > bytes) {
// keep a single block around if it does not exceed
// the basic block size, to avoid repeated allocations
// between uses of the buffer
if (bufferSize <= bytes) {
- if (buffers.first().size() <= basicBlockSize) {
+ if (buffers.constFirst().size() <= basicBlockSize) {
bufferSize = 0;
head = tail = 0;
} else {
@@ -100,20 +108,25 @@ char *QRingBuffer::reserve(qint64 bytes)
if (bytes <= 0 || bytes >= MaxByteArraySize)
return 0;
- const qint64 newSize = bytes + tail;
- // if need buffer reallocation
- if (newSize > buffers.last().size()) {
- if (newSize > buffers.last().capacity() && (tail >= basicBlockSize
- || newSize >= MaxByteArraySize)) {
- // shrink this buffer to its current size
- buffers.last().resize(tail);
-
- // create a new QByteArray
- buffers.append(QByteArray());
- ++tailBuffer;
- tail = 0;
+ if (buffers.isEmpty()) {
+ buffers.append(QByteArray());
+ buffers.first().resize(qMax(basicBlockSize, int(bytes)));
+ } else {
+ const qint64 newSize = bytes + tail;
+ // if need buffer reallocation
+ if (newSize > buffers.constLast().size()) {
+ if (newSize > buffers.constLast().capacity() && (tail >= basicBlockSize
+ || newSize >= MaxByteArraySize)) {
+ // shrink this buffer to its current size
+ buffers.last().resize(tail);
+
+ // create a new QByteArray
+ buffers.append(QByteArray());
+ ++tailBuffer;
+ tail = 0;
+ }
+ buffers.last().resize(qMax(basicBlockSize, tail + int(bytes)));
}
- buffers.last().resize(qMax(basicBlockSize, tail + int(bytes)));
}
char *writePtr = buffers.last().data() + tail;
@@ -134,9 +147,13 @@ char *QRingBuffer::reserveFront(qint64 bytes)
return 0;
if (head < bytes) {
- buffers.first().remove(0, head);
- if (tailBuffer == 0)
- tail -= head;
+ if (buffers.isEmpty()) {
+ buffers.append(QByteArray());
+ } else {
+ buffers.first().remove(0, head);
+ if (tailBuffer == 0)
+ tail -= head;
+ }
head = qMax(basicBlockSize, int(bytes));
if (bufferSize == 0) {
@@ -155,13 +172,15 @@ char *QRingBuffer::reserveFront(qint64 bytes)
void QRingBuffer::chop(qint64 bytes)
{
+ Q_ASSERT(bytes <= bufferSize);
+
while (bytes > 0) {
if (tailBuffer == 0 || tail > bytes) {
// keep a single block around if it does not exceed
// the basic block size, to avoid repeated allocations
// between uses of the buffer
if (bufferSize <= bytes) {
- if (buffers.first().size() <= basicBlockSize) {
+ if (buffers.constFirst().size() <= basicBlockSize) {
bufferSize = 0;
head = tail = 0;
} else {
@@ -179,12 +198,15 @@ void QRingBuffer::chop(qint64 bytes)
bytes -= tail;
buffers.removeLast();
--tailBuffer;
- tail = buffers.last().size();
+ tail = buffers.constLast().size();
}
}
void QRingBuffer::clear()
{
+ if (buffers.isEmpty())
+ return;
+
buffers.erase(buffers.begin() + 1, buffers.end());
buffers.first().clear();
@@ -193,20 +215,32 @@ void QRingBuffer::clear()
bufferSize = 0;
}
-qint64 QRingBuffer::indexOf(char c, qint64 maxLength) const
+qint64 QRingBuffer::indexOf(char c, qint64 maxLength, qint64 pos) const
{
- qint64 index = 0;
- qint64 j = head;
- for (int i = 0; index < maxLength && i < buffers.size(); ++i) {
- const char *ptr = buffers[i].constData() + j;
- j = qMin(index + (i == tailBuffer ? tail : buffers[i].size()) - j, maxLength);
-
- while (index < j) {
- if (*ptr++ == c)
- return index;
- ++index;
+ if (maxLength <= 0 || pos < 0)
+ return -1;
+
+ qint64 index = -(pos + head);
+ for (int i = 0; i < buffers.size(); ++i) {
+ const qint64 nextBlockIndex = qMin(index + (i == tailBuffer ? tail : buffers[i].size()),
+ maxLength);
+
+ if (nextBlockIndex > 0) {
+ const char *ptr = buffers[i].constData();
+ if (index < 0) {
+ ptr -= index;
+ index = 0;
+ }
+
+ const char *findPtr = reinterpret_cast<const char *>(memchr(ptr, c,
+ nextBlockIndex - index));
+ if (findPtr)
+ return qint64(findPtr - ptr) + index + pos;
+
+ if (nextBlockIndex == maxLength)
+ return -1;
}
- j = 0;
+ index = nextBlockIndex;
}
return -1;
}
@@ -242,7 +276,6 @@ QByteArray QRingBuffer::read()
if (tailBuffer == 0) {
qba.resize(tail);
tail = 0;
- buffers.append(QByteArray());
} else {
--tailBuffer;
}
@@ -283,12 +316,29 @@ qint64 QRingBuffer::peek(char *data, qint64 maxLength, qint64 pos) const
/*!
\internal
+ Append bytes from data to the end
+*/
+void QRingBuffer::append(const char *data, qint64 size)
+{
+ char *writePointer = reserve(size);
+ if (size == 1)
+ *writePointer = *data;
+ else if (size)
+ ::memcpy(writePointer, data, size);
+}
+
+/*!
+ \internal
+
Append a new buffer to the end
*/
void QRingBuffer::append(const QByteArray &qba)
{
if (tail == 0) {
- buffers.last() = qba;
+ if (buffers.isEmpty())
+ buffers.append(qba);
+ else
+ buffers.last() = qba;
} else {
buffers.last().resize(tail);
buffers.append(qba);