QStringConverterICU: Pass correct pointer to callback

Pass the pointer to the current state, not a pointer to a pointer to it.

[ChangeLog][QtCore][QStringConverter] Fixed a bug involving moved
QStringEncoder/QStringDecoder objects accessing invalid state.

Amends 122270d6bea164e6df4357f4d4d77aacfa430470.

Done-with: Marc Mutz <[email protected]>
Change-Id: I70d4dc00e3e0db6cad964579662bcf6d185a4c34
Reviewed-by: Fabian Kosmale <[email protected]>
Reviewed-by: Mårten Nordheim <[email protected]>
(cherry picked from commit 39bbfce9b675c9085ef49c9b9c52c146eca55e4a)
Reviewed-by: Qt Cherry-pick Bot <[email protected]>
(cherry picked from commit 7c4e1357e49baebdd2d20710fccb5604cbb36c0d)

2 files changed, 44 insertions, 32 deletions

diff --git a/src/corelib/text/qstringconverter.cpp b/src/corelib/text/qstringconverter.cpp
index 6ca65ba6ad8..043b8f54151 100644
--- a/src/corelib/text/qstringconverter.cpp
+++ b/src/corelib/text/qstringconverter.cpp
@@ -1966,7 +1966,7 @@ struct QStringConverterICU : QStringConverter
         const void *context;
         ucnv_getToUCallBack(icu_conv, &action, &context);
         if (context != state)
-             ucnv_setToUCallBack(icu_conv, action, &state, nullptr, nullptr, &err);
+             ucnv_setToUCallBack(icu_conv, action, state, nullptr, nullptr, &err);
 
         ucnv_toUnicode(icu_conv, &target, targetLimit, &source, sourceLimit, nullptr, flush, &err);
         // We did reserve enough space:
@@ -1999,7 +1999,7 @@ struct QStringConverterICU : QStringConverter
         const void *context;
         ucnv_getFromUCallBack(icu_conv, &action, &context);
         if (context != state)
-             ucnv_setFromUCallBack(icu_conv, action, &state, nullptr, nullptr, &err);
+             ucnv_setFromUCallBack(icu_conv, action, state, nullptr, nullptr, &err);
 
         ucnv_fromUnicode(icu_conv, &target, targetLimit, &source, sourceLimit, nullptr, flush, &err);
         // We did reserve enough space:
diff --git a/tests/auto/corelib/text/qstringconverter/tst_qstringconverter.cpp b/tests/auto/corelib/text/qstringconverter/tst_qstringconverter.cpp
index f37935f6655..ebe6280385a 100644
--- a/tests/auto/corelib/text/qstringconverter/tst_qstringconverter.cpp
+++ b/tests/auto/corelib/text/qstringconverter/tst_qstringconverter.cpp
@@ -540,11 +540,10 @@ void tst_QStringConverter::charByCharConsistency_data()
 
 void tst_QStringConverter::charByCharConsistency()
 {
-    QFETCH(QStringView, source);
-    QFETCH(QByteArray, codec);
+    QFETCH(const QStringView, source);
+    QFETCH(const QByteArray, codec);
 
-    {
-        QStringEncoder encoder(codec);
+    const auto check = [&](QStringEncoder encoder){
         if (!encoder.isValid())
             QSKIP("Unsupported codec");
 
@@ -555,19 +554,28 @@ void tst_QStringConverter::charByCharConsistency()
             stepByStepConverted += encoder.encode(codeUnit);
         }
         QCOMPARE(stepByStepConverted, fullyConverted);
-    }
+    };
+
+    check(QStringEncoder(codec));
+    if (QTest::currentTestResolved()) return;
+
+    check(QStringEncoder(codec, QStringConverter::Flag::ConvertInvalidToNull));
+    if (QTest::currentTestResolved()) return;
+
+    // moved codecs also work:
 
     {
-        QStringEncoder encoder(codec, QStringConverter::Flag::ConvertInvalidToNull);
+        QStringEncoder dec(codec);
+        check(std::move(dec));
+    }
+    if (QTest::currentTestResolved()) return;
 
-        QByteArray fullyConverted = encoder.encode(source);
-        encoder.resetState();
-        QByteArray stepByStepConverted;
-        for (const auto& codeUnit: source) {
-            stepByStepConverted += encoder.encode(codeUnit);
-        }
-        QCOMPARE(stepByStepConverted, fullyConverted);
+    {
+        QStringEncoder dec(codec, QStringConverter::Flag::ConvertInvalidToNull);
+        check(std::move(dec));
     }
+    if (QTest::currentTestResolved()) return;
+
 }
 
 void tst_QStringConverter::byteByByteConsistency_data()
@@ -584,11 +592,10 @@ void tst_QStringConverter::byteByByteConsistency_data()
 
 void tst_QStringConverter::byteByByteConsistency()
 {
-    QFETCH(QByteArray, source);
-    QFETCH(QByteArray, codec);
+    QFETCH(const QByteArray, source);
+    QFETCH(const QByteArray, codec);
 
-    {
-        QStringDecoder decoder(codec);
+    const auto check = [&](QStringDecoder decoder) {
         if (!decoder.isValid())
             QSKIP("Unsupported codec");
 
@@ -601,23 +608,28 @@ void tst_QStringConverter::byteByByteConsistency()
             stepByStepConverted += decoder.decode(singleChar);
         }
         QCOMPARE(stepByStepConverted, fullyConverted);
-    }
+    };
+
+    check(QStringDecoder(codec));
+    if (QTest::currentTestResolved()) return;
+
+    check(QStringDecoder(codec, QStringConverter::Flag::ConvertInvalidToNull));
+    if (QTest::currentTestResolved()) return;
+
+    // moved codecs also work:
 
     {
-        QStringDecoder decoder(codec, QStringConverter::Flag::ConvertInvalidToNull);
-        if (!decoder.isValid())
-            QSKIP("Unsupported codec");
+        QStringDecoder dec(codec);
+        check(std::move(dec));
+    }
+    if (QTest::currentTestResolved()) return;
 
-        QString fullyConverted = decoder.decode(source);
-        decoder.resetState();
-        QString stepByStepConverted;
-        for (const auto& byte: source) {
-            QByteArray singleChar;
-            singleChar.append(byte);
-            stepByStepConverted += decoder.decode(singleChar);
-        }
-        QCOMPARE(stepByStepConverted, fullyConverted);
+    {
+        QStringDecoder dec(codec, QStringConverter::Flag::ConvertInvalidToNull);
+        check(std::move(dec));
     }
+    if (QTest::currentTestResolved()) return;
+
 }
 
 void tst_QStringConverter::statefulPieceWise()