Add a function to parse IPv4 addresses in QtCore

In the unit test, check against inet_aton on Linux with GLIBC
only. Other platforms have this function too, but they sometimes have
different behaviour, so don't try to test them equally.

Change-Id: I1a77e405ac7e713d4cf1cee03ea5ce17fb47feef
Reviewed-by: João Abecasis <joao.abecasis@nokia.com>
Reviewed-by: Shane Kearns <shane.kearns@accenture.com>

3 files changed, 204 insertions, 0 deletions

diff --git a/src/corelib/io/io.pri b/src/corelib/io/io.pri
index 9c117abe03..a3bc3afbcf 100644
--- a/src/corelib/io/io.pri
+++ b/src/corelib/io/io.pri
@@ -15,6 +15,7 @@ HEADERS +=  \
         io/qfiledevice_p.h \
         io/qfileinfo.h \
         io/qfileinfo_p.h \
+        io/qipaddress_p.h \
         io/qiodevice.h \
         io/qiodevice_p.h \
         io/qnoncontiguousbytedevice_p.h \
@@ -53,6 +54,7 @@ SOURCES += \
         io/qfile.cpp \
         io/qfiledevice.cpp \
         io/qfileinfo.cpp \
+        io/qipaddress.cpp \
         io/qiodevice.cpp \
         io/qnoncontiguousbytedevice.cpp \
         io/qprocess.cpp \
diff --git a/src/corelib/io/qipaddress.cpp b/src/corelib/io/qipaddress.cpp
new file mode 100644
index 0000000000..b8871fe8b9
--- /dev/null
+++ b/src/corelib/io/qipaddress.cpp
@@ -0,0 +1,131 @@
+/****************************************************************************
+**
+** Copyright (C) 2012 Intel Corporation
+** Contact: http://www.qt-project.org/
+**
+** 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 "qipaddress_p.h"
+#include "private/qlocale_tools_p.h"
+#include "qvarlengtharray.h"
+
+QT_BEGIN_NAMESPACE
+namespace QIPAddressUtils {
+
+static QString number(quint8 val, int base = 10)
+{
+    QChar zero(0x30);
+    return val ? qulltoa(val, base, zero) : zero;
+}
+
+typedef QVarLengthArray<char, 64> Buffer;
+static bool checkedToAscii(Buffer &buffer, const QChar *begin, const QChar *end)
+{
+    const ushort *const ubegin = reinterpret_cast<const ushort *>(begin);
+    const ushort *const uend = reinterpret_cast<const ushort *>(end);
+    const ushort *src = ubegin;
+
+    buffer.resize(uend - ubegin + 1);
+    char *dst = buffer.data();
+
+    while (src != uend) {
+        if (*src >= 0x7f)
+            return false;
+        *dst++ = *src++;
+    }
+    *dst = '\0';
+    return true;
+}
+
+bool parseIp4(IPv4Address &address, const QChar *begin, const QChar *end)
+{
+    Q_ASSERT(begin != end);
+    Buffer buffer;
+    if (!checkedToAscii(buffer, begin, end))
+        return false;
+
+    int dotCount = 0;
+    address = 0;
+    const char *ptr = buffer.data();
+    while (dotCount < 4) {
+        const char *endptr;
+        bool ok;
+        quint64 ll = qstrtoull(ptr, &endptr, 0, &ok);
+        quint32 x = ll;
+        if (!ok || endptr == ptr || ll != x)
+            return false;
+
+        if (*endptr == '.' || dotCount == 3) {
+            if (x & ~0xff)
+                return false;
+            address <<= 8;
+        } else if (dotCount == 2) {
+            if (x & ~0xffff)
+                return false;
+            address <<= 16;
+        } else if (dotCount == 1) {
+            if (x & ~0xffffff)
+                return false;
+            address <<= 24;
+        }
+        address |= x;
+
+        if (dotCount == 3 && *endptr != '\0')
+            return false;
+        else if (dotCount == 3 || *endptr == '\0')
+            return true;
+        ++dotCount;
+        ptr = endptr + 1;
+    }
+    return false;
+}
+
+void toString(QString &appendTo, IPv4Address address)
+{
+    // reconstructing is easy
+    // use the fast operator% that pre-calculates the size
+    appendTo += number(address >> 24)
+                % QLatin1Char('.')
+                % number(address >> 16)
+                % QLatin1Char('.')
+                % number(address >> 8)
+                % QLatin1Char('.')
+                % number(address);
+}
+
+}
+QT_END_NAMESPACE
diff --git a/src/corelib/io/qipaddress_p.h b/src/corelib/io/qipaddress_p.h
new file mode 100644
index 0000000000..f3bcf76424
--- /dev/null
+++ b/src/corelib/io/qipaddress_p.h
@@ -0,0 +1,71 @@
+/****************************************************************************
+**
+** Copyright (C) 2012 Intel Corporation
+** Contact: http://www.qt-project.org/
+**
+** 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.
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QIPADDRESS_P_H
+#define QIPADDRESS_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API. It exists for the convenience of
+// qurl*.cpp This header file may change from version to version without
+// notice, or even be removed.
+//
+// We mean it.
+//
+
+#include "qstring.h"
+
+QT_BEGIN_NAMESPACE
+
+namespace QIPAddressUtils {
+
+typedef quint32 IPv4Address;
+
+Q_CORE_EXPORT bool parseIp4(IPv4Address &address, const QChar *begin, const QChar *end);
+Q_CORE_EXPORT void toString(QString &appendTo, IPv4Address address);
+
+} // namespace
+
+QT_END_NAMESPACE
+
+#endif // QIPADDRESS_P_H