From 38c2e3d1049f494529cb9876bcd564ec20ba512c Mon Sep 17 00:00:00 2001
From: Lars Knoll <lars.knoll@digia.com>
Date: Mon, 1 Sep 2014 14:26:51 +0200
Subject: [PATCH] Properly detect UTF-8 BOM markers in ini files
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

If we detect a utf8 BOM mark at the beginning of the .ini
file, skip the marker and set the iniCodec to utf8.

Task-number: QTBUG-23381
Change-Id: I1b37fc4f1638a48e4f3ee71ab165e2989bc592f1
Reviewed-by: Jędrzej Nowacki <jedrzej.nowacki@digia.com>
---
 src/corelib/io/qsettings.cpp                    |  9 +++++++++
 src/corelib/io/qsettings_p.h                    |  2 +-
 tests/auto/corelib/io/qsettings/bom.ini         |  4 ++++
 tests/auto/corelib/io/qsettings/qsettings.qrc   | 17 +++++++++--------
 .../auto/corelib/io/qsettings/tst_qsettings.cpp | 10 ++++++++++
 5 files changed, 33 insertions(+), 9 deletions(-)
 create mode 100644 tests/auto/corelib/io/qsettings/bom.ini

diff --git a/src/corelib/io/qsettings.cpp b/src/corelib/io/qsettings.cpp
index d896da176a..ebca7d57ff 100644
--- a/src/corelib/io/qsettings.cpp
+++ b/src/corelib/io/qsettings.cpp
@@ -1637,6 +1637,15 @@ bool QConfFileSettingsPrivate::readIniFile(const QByteArray &data,
     int sectionPosition = 0;
     bool ok = true;
 
+#ifndef QT_NO_TEXTCODEC
+    // detect utf8 BOM
+    const uchar *dd = (const uchar *)data.constData();
+    if (data.size() >= 3 && dd[0] == 0xef && dd[1] == 0xbb && dd[2] == 0xbf) {
+        iniCodec = QTextCodec::codecForName("UTF-8");
+        dataPos = 3;
+    }
+#endif
+
     while (readIniLine(data, dataPos, lineStart, lineLen, equalsPos)) {
         char ch = data.at(lineStart);
         if (ch == '[') {
diff --git a/src/corelib/io/qsettings_p.h b/src/corelib/io/qsettings_p.h
index cb29b4c83a..715f13530a 100644
--- a/src/corelib/io/qsettings_p.h
+++ b/src/corelib/io/qsettings_p.h
@@ -282,7 +282,7 @@ public:
     bool isWritable() const;
     QString fileName() const;
 
-    static bool readIniFile(const QByteArray &data, UnparsedSettingsMap *unparsedIniSections);
+    bool readIniFile(const QByteArray &data, UnparsedSettingsMap *unparsedIniSections);
     static bool readIniSection(const QSettingsKey &section, const QByteArray &data,
                                ParsedSettingsMap *settingsMap, QTextCodec *codec);
     static bool readIniLine(const QByteArray &data, int &dataPos, int &lineStart, int &lineLen,
diff --git a/tests/auto/corelib/io/qsettings/bom.ini b/tests/auto/corelib/io/qsettings/bom.ini
new file mode 100644
index 0000000000..8d46ee8d91
--- /dev/null
+++ b/tests/auto/corelib/io/qsettings/bom.ini
@@ -0,0 +1,4 @@
+[section1]
+foo1=bar1
+[section2]
+foo2=bar2
diff --git a/tests/auto/corelib/io/qsettings/qsettings.qrc b/tests/auto/corelib/io/qsettings/qsettings.qrc
index 587c22ebe3..c0be7e013f 100644
--- a/tests/auto/corelib/io/qsettings/qsettings.qrc
+++ b/tests/auto/corelib/io/qsettings/qsettings.qrc
@@ -1,9 +1,10 @@
-<!DOCTYPE RCC><RCC version="1.0">
-<qresource>
-    <file>resourcefile.ini</file>
-    <file>resourcefile2.ini</file>
-    <file>resourcefile3.ini</file>
-    <file>resourcefile4.ini</file>
-    <file>resourcefile5.ini</file>
-</qresource>
+<RCC>
+    <qresource prefix="/">
+        <file>resourcefile.ini</file>
+        <file>resourcefile2.ini</file>
+        <file>resourcefile3.ini</file>
+        <file>resourcefile4.ini</file>
+        <file>resourcefile5.ini</file>
+        <file>bom.ini</file>
+    </qresource>
 </RCC>
diff --git a/tests/auto/corelib/io/qsettings/tst_qsettings.cpp b/tests/auto/corelib/io/qsettings/tst_qsettings.cpp
index 3e68e4859f..c89923f159 100644
--- a/tests/auto/corelib/io/qsettings/tst_qsettings.cpp
+++ b/tests/auto/corelib/io/qsettings/tst_qsettings.cpp
@@ -161,6 +161,7 @@ private slots:
     void testByteArray_data();
     void testByteArray();
     void iniCodec();
+    void bom();
 
 private:
     const bool m_canWriteNativeSystemSettings;
@@ -730,6 +731,15 @@ void tst_QSettings::iniCodec()
 
 }
 
+void tst_QSettings::bom()
+{
+    QSettings s(":/bom.ini", QSettings::IniFormat);
+    QStringList allkeys = s.allKeys();
+    QCOMPARE(allkeys.size(), 2);
+    QVERIFY(allkeys.contains("section1/foo1"));
+    QVERIFY(allkeys.contains("section2/foo2"));
+}
+
 void tst_QSettings::testErrorHandling_data()
 {
     QTest::addColumn<int>("filePerms"); // -1 means file should not exist