SQL/MySQL: Add support for Bit-Value Type - BIT

Add support for MYSQL_TYPE_BIT. Since the bitfield can be max 64bits,
store it in a uint64_t. Writing such a value as MYSQL_TYPE_LONGLONG
works as expected but receiving it needs a special handling.

[ChangeLog][SQL][MySQL] Added handling for Bit-Value Type - BIT.

Fixes: QTBUG-21326
Change-Id: Id20e3316caf6703b3bec8a828144494a20693fd8
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>

src/plugins/sqldrivers/mysql/qsql_mysql.cpp

@@ -215,6 +215,7 @@ static QMetaType qDecodeMYSQLType(enum_field_types mysqltype, uint flags)
     case MYSQL_TYPE_YEAR:
         type = QMetaType::Int;
         break;
+    case MYSQL_TYPE_BIT:
     case MYSQL_TYPE_LONGLONG:
         type = (flags & UNSIGNED_FLAG) ? QMetaType::ULongLong : QMetaType::LongLong;
         break;
@@ -303,6 +304,11 @@ static bool qIsInteger(int t)
         || t == QMetaType::LongLong || t == QMetaType::ULongLong;
 }
 
+static inline bool qIsBitfield(enum_field_types type)
+{
+    return type == MYSQL_TYPE_BIT;
+}
+
 void QMYSQLResultPrivate::bindBlobs()
 {
     for (int i = 0; i < fields.size(); ++i) {
@@ -519,6 +525,20 @@ bool QMYSQLResult::fetchFirst()
     return fetch(0);
 }
 
+static inline uint64_t
+qDecodeBitfield(const QMYSQLResultPrivate::QMyField &f, const char *outField)
+{
+    // byte-aligned length
+    const auto numBytes = (f.myField->length + 7) / 8;
+    uint64_t val = 0;
+    for (unsigned long i = 0; i < numBytes && outField; ++i) {
+        uint64_t tmp = static_cast<uint8_t>(outField[i]);
+        val <<= 8;
+        val |= tmp;
+    }
+    return val;
+}
+
 QVariant QMYSQLResult::data(int field)
 {
     Q_D(QMYSQLResult);
@@ -536,8 +556,9 @@ QVariant QMYSQLResult::data(int field)
     if (d->preparedQuery) {
         if (f.nullIndicator)
             return QVariant(f.type);
-
+        if (qIsBitfield(f.myField->type)) {
-        if (qIsInteger(f.type.id())) {
+            return QVariant::fromValue(qDecodeBitfield(f, f.outField));
+        } else if (qIsInteger(f.type.id())) {
             QVariant variant(f.type, f.outField);
             // we never want to return char variants here, see QTBUG-53397
             if (f.type.id() == QMetaType::UChar)
@@ -569,6 +590,9 @@ QVariant QMYSQLResult::data(int field)
             return QVariant(f.type);
         }
 
+        if (qIsBitfield(f.myField->type))
+            return QVariant::fromValue(qDecodeBitfield(f, d->row[field]));
+
         fieldLength = mysql_fetch_lengths(d->result)[field];
 
         if (f.type.id() != QMetaType::QByteArray)
@@ -677,6 +701,7 @@ bool QMYSQLResult::reset (const QString& query)
         for(int i = 0; i < numFields; i++) {
             MYSQL_FIELD* field = mysql_fetch_field_direct(d->result, i);
             d->fields[i].type = qDecodeMYSQLType(field->type, field->flags);
+            d->fields[i].myField = field;
         }
         setAt(QSql::BeforeFirstRow);
     }
@@ -794,6 +819,7 @@ bool QMYSQLResult::nextResult()
         for (unsigned int i = 0; i < numFields; i++) {
             MYSQL_FIELD *field = mysql_fetch_field_direct(d->result, i);
             d->fields[i].type = qDecodeMYSQLType(field->type, field->flags);
+            d->fields[i].myField = field;
         }
     }
 

tests/auto/sql/kernel/qsqlquery/tst_qsqlquery.cpp

@@ -4629,6 +4629,13 @@ void tst_QSqlQuery::integralTypesMysql()
         runIntegralTypesMysqlTest<qint64>(db, "bigIntTest", "BIGINT", withPreparedStatement);
         runIntegralTypesMysqlTest<quint64>(db, "unsignedBigIntTest", "BIGINT UNSIGNED",
                                            withPreparedStatement);
+        runIntegralTypesMysqlTest<quint64>(db, "bitmask_7", "BIT(7)", withPreparedStatement, 0,
+                                           (1LL << 7) - 1);
+        runIntegralTypesMysqlTest<quint64>(db, "bitmask_31", "BIT(31)", withPreparedStatement, 0,
+                                           (1LL << 31) - 1);
+        runIntegralTypesMysqlTest<quint64>(db, "bitmask_33", "BIT(33)", withPreparedStatement, 0,
+                                           (1LL << 33) - 1);
+        runIntegralTypesMysqlTest<quint64>(db, "bitmask_64", "BIT(64)", withPreparedStatement);
     }
 }