From 37a7b035f8feb248d25741b22e22ffb0ec7463d6 Mon Sep 17 00:00:00 2001 From: Lars Knoll Date: Wed, 18 Jan 2012 10:12:50 +0100 Subject: Import json support from playground/qtbinaryjson This imports the JSON support for Qt 5 from playground/qtbinaryjson. It adds a fast, fully compliant json parser, a convenient C++ API, conversion to and from QVariants and a binary format for JSON that is extremely fast to use together with the C++ API. Change-Id: If9e3a21a4241d388d0abaa446b6824f9cc6edb1c Reviewed-by: Thiago Macieira --- src/corelib/json/qjson.cpp | 427 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 427 insertions(+) create mode 100644 src/corelib/json/qjson.cpp (limited to 'src/corelib/json/qjson.cpp') diff --git a/src/corelib/json/qjson.cpp b/src/corelib/json/qjson.cpp new file mode 100644 index 0000000000..dedddfcfad --- /dev/null +++ b/src/corelib/json/qjson.cpp @@ -0,0 +1,427 @@ +/**************************************************************************** +** +** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies). +** All rights reserved. +** Contact: Nokia Corporation (qt-info@nokia.com) +** +** This file is part of the QtCore module of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** GNU Lesser General Public License Usage +** This file may be used under the terms of the GNU Lesser General Public +** License version 2.1 as published by the Free Software Foundation and +** appearing in the file LICENSE.LGPL included in the packaging of this +** file. Please review the following information to ensure the GNU Lesser +** General Public License version 2.1 requirements will be met: +** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. +** +** In addition, as a special exception, Nokia gives you certain additional +** rights. These rights are described in the Nokia Qt 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 3.0 as published by the Free Software Foundation +** and appearing in the file LICENSE.GPL included in the packaging of this +** file. Please review the following information to ensure the GNU General +** Public License version 3.0 requirements will be met: +** http://www.gnu.org/copyleft/gpl.html. +** +** Other Usage +** Alternatively, this file may be used in accordance with the terms and +** conditions contained in a signed written agreement between you and Nokia. +** +** +** +** +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include "qjson_p.h" +#include + +QT_BEGIN_NAMESPACE + +namespace QJsonPrivate +{ + +#ifdef Q_LITTLE_ENDIAN +#define Q_TO_LITTLE_ENDIAN(x) (x) +#else +#define Q_TO_LITTLE_ENDIAN(x) ( ((x & 0xff) << 24) | ((x & 0xff00) << 8) | ((x & 0xff0000) >> 8) | ((x & 0xff000000) >> 24) ) +#endif + +static const Base emptyArray = { { Q_TO_LITTLE_ENDIAN(sizeof(Base)) }, { 0 }, { 0 } }; +static const Base emptyObject = { { Q_TO_LITTLE_ENDIAN(sizeof(Base)) }, { 0 }, { 0 } }; + + +void Data::compact() +{ + Q_ASSERT(sizeof(Value) == sizeof(offset)); + + if (!compactionCounter) + return; + + Base *base = header->root(); + int reserve = 0; + if (base->is_object) { + Object *o = static_cast(base); + for (int i = 0; i < (int)o->length; ++i) + reserve += o->entryAt(i)->usedStorage(o); + } else { + Array *a = static_cast(base); + for (int i = 0; i < (int)a->length; ++i) + reserve += (*a)[i].usedStorage(a); + } + + int size = sizeof(Base) + reserve + base->length*sizeof(offset); + int alloc = sizeof(Header) + size; + Header *h = (Header *) malloc(alloc); + h->tag = QJsonDocument::BinaryFormatTag; + h->version = 1; + Base *b = h->root(); + b->size = size; + b->is_object = header->root()->is_object; + b->length = base->length; + b->tableOffset = reserve + sizeof(Array); + + int offset = sizeof(Base); + if (b->is_object) { + Object *o = static_cast(base); + Object *no = static_cast(b); + + for (int i = 0; i < (int)o->length; ++i) { + no->table()[i] = offset; + + const Entry *e = o->entryAt(i); + Entry *ne = no->entryAt(i); + int s = e->size(); + memcpy(ne, e, s); + offset += s; + int dataSize = e->value.usedStorage(o); + if (dataSize) { + memcpy((char *)no + offset, e->value.data(o), dataSize); + ne->value.value = offset; + offset += dataSize; + } + } + } else { + Array *a = static_cast(base); + Array *na = static_cast(b); + + for (int i = 0; i < (int)a->length; ++i) { + const Value &v = (*a)[i]; + Value &nv = (*na)[i]; + nv = v; + int dataSize = v.usedStorage(a); + if (dataSize) { + memcpy((char *)na + offset, v.data(a), dataSize); + nv.value = offset; + offset += dataSize; + } + } + } + Q_ASSERT(offset == (int)b->tableOffset); + + free(header); + header = h; + alloc = alloc; + compactionCounter = 0; +} + +bool Data::valid() const +{ + if (header->tag != QJsonDocument::BinaryFormatTag || header->version != 1u) + return false; + + bool res = false; + if (header->root()->is_object) + res = static_cast(header->root())->isValid(); + else + res = static_cast(header->root())->isValid(); + + return res; +} + + +int Base::reserveSpace(uint dataSize, int posInTable, uint numItems, bool replace) +{ + Q_ASSERT(posInTable >= 0 && posInTable <= (int)length); + + offset off = tableOffset; + // move table to new position + if (replace) { + memmove((char *)(table()) + dataSize, table(), length*sizeof(offset)); + } else { + memmove((char *)(table() + posInTable + numItems) + dataSize, table() + posInTable, (length - posInTable)*sizeof(offset)); + memmove((char *)(table()) + dataSize, table(), posInTable*sizeof(offset)); + } + tableOffset += dataSize; + for (int i = 0; i < (int)numItems; ++i) + table()[posInTable + i] = off; + size += dataSize; + if (!replace) { + length += numItems; + size += numItems * sizeof(offset); + } + return off; +} + +void Base::removeItems(int pos, int numItems) +{ + Q_ASSERT(pos >= 0 && pos <= (int)length); + if (pos + numItems < (int)length) + memmove(table() + pos, table() + pos + numItems, (length - pos - numItems)*sizeof(offset)); + length -= numItems; +} + +int Object::indexOf(const QString &key, bool *exists) +{ + int min = 0; + int n = length; + while (n > 0) { + int half = n >> 1; + int middle = min + half; + if (*entryAt(middle) >= key) { + n = half; + } else { + min = middle + 1; + n -= half + 1; + } + } + if (min < (int)length && *entryAt(min) == key) { + *exists = true; + return min; + } + *exists = false; + return min; +} + +bool Object::isValid() const +{ + if (tableOffset + length*sizeof(offset) > size) + return false; + + for (uint i = 0; i < length; ++i) { + offset entryOffset = table()[i]; + if (entryOffset + sizeof(Entry) >= tableOffset) + return false; + Entry *e = entryAt(i); + int s = e->size(); + if (table()[i] + s > tableOffset) + return false; + if (!e->value.isValid(this)) + return false; + } + return true; +} + + + +bool Array::isValid() const +{ + if (tableOffset + length*sizeof(offset) > size) + return false; + + for (uint i = 0; i < length; ++i) { + if (!at(i).isValid(this)) + return false; + } + return true; +} + + +bool Entry::operator ==(const QString &key) const +{ + if (value.latinKey) + return (shallowLatin1Key() == key); + else + return (shallowKey() == key); +} + +bool Entry::operator >=(const QString &key) const +{ + if (value.latinKey) + return (shallowLatin1Key() >= key); + else + return (shallowKey() >= key); +} + +bool Entry::operator ==(const Entry &other) const +{ + if (value.latinKey) { + if (other.value.latinKey) + return shallowLatin1Key() == other.shallowLatin1Key(); + return shallowLatin1Key() == other.shallowKey(); + } else if (other.value.latinKey) { + return shallowKey() == other.shallowLatin1Key(); + } + return shallowKey() == other.shallowKey(); +} + +bool Entry::operator >=(const Entry &other) const +{ + if (value.latinKey) { + if (other.value.latinKey) + return shallowLatin1Key() >= other.shallowLatin1Key(); + return shallowLatin1Key() >= other.shallowKey(); + } else if (other.value.latinKey) { + return shallowKey() >= other.shallowLatin1Key(); + } + return shallowKey() >= other.shallowKey(); +} + + +int Value::usedStorage(const Base *b) const +{ + int s = 0; + switch (type) { + case QJsonValue::Double: + if (latinOrIntValue) + break; + s = sizeof(double); + break; + case QJsonValue::String: { + char *d = data(b); + if (latinOrIntValue) + s = sizeof(ushort) + *(ushort *)d; + else + s = sizeof(int) + sizeof(ushort)*(*(int *)d); + break; + } + case QJsonValue::Array: + case QJsonValue::Object: + s = base(b)->size; + break; + case QJsonValue::Null: + case QJsonValue::Bool: + default: + break; + } + return alignedSize(s); +} + +bool Value::isValid(const Base *b) const +{ + int offset = 0; + switch (type) { + case QJsonValue::Double: + if (latinOrIntValue) + break; + // fall through + case QJsonValue::String: + case QJsonValue::Array: + case QJsonValue::Object: + offset = value; + break; + case QJsonValue::Null: + case QJsonValue::Bool: + default: + break; + } + + if (!offset) + return true; + if (offset + sizeof(uint) > b->tableOffset) + return false; + + int s = usedStorage(b); + if (!s) + return true; + if (s < 0 || offset + s > (int)b->tableOffset) + return false; + if (type == QJsonValue::Array) + return static_cast(base(b))->isValid(); + if (type == QJsonValue::Object) + return static_cast(base(b))->isValid(); + return true; +} + +/*! + \internal + */ +int Value::requiredStorage(const QJsonValue &v, bool *compressed) +{ + *compressed = false; + switch (v.t) { + case QJsonValue::Double: + if (QJsonPrivate::compressedNumber(v.dbl) != INT_MAX) { + *compressed = true; + return 0; + } + return sizeof(double); + case QJsonValue::String: { + QString s = v.toString(); + *compressed = QJsonPrivate::useCompressed(s); + return QJsonPrivate::qStringSize(s, *compressed); + } + case QJsonValue::Array: + case QJsonValue::Object: + return v.base ? v.base->size : sizeof(QJsonPrivate::Base); + case QJsonValue::Undefined: + case QJsonValue::Null: + case QJsonValue::Bool: + break; + } + return 0; +} + +/*! + \internal + */ +uint Value::valueToStore(const QJsonValue &v, uint offset) +{ + switch (v.t) { + case QJsonValue::Undefined: + case QJsonValue::Null: + break; + case QJsonValue::Bool: + return v.b; + case QJsonValue::Double: { + int c = QJsonPrivate::compressedNumber(v.dbl); + if (c != INT_MAX) + return c; + } + // fall through + case QJsonValue::String: + case QJsonValue::Array: + case QJsonValue::Object: + return offset; + } + return 0; +} + +/*! + \internal + */ +void Value::copyData(const QJsonValue &v, char *dest, bool compressed) +{ + switch (v.t) { + case QJsonValue::Double: + if (!compressed) { + qToLittleEndian(v.ui, (uchar *)dest); + } + break; + case QJsonValue::String: { + QString str = v.toString(); + QJsonPrivate::copyString(dest, str, compressed); + break; + } + case QJsonValue::Array: + case QJsonValue::Object: { + const QJsonPrivate::Base *b = v.base; + if (!b) + b = (v.t == QJsonValue::Array ? &emptyArray : &emptyObject); + memcpy(dest, b, b->size); + break; + } + default: + break; + } +} + +} // namespace QJsonPrivate + +QT_END_NAMESPACE -- cgit v1.2.3