SQL/ODBC: misc cleanup

Misc cleanup
 - merge qGetIntData and qGetBigIntData
 - remove unused braces
 - properly initialize values

Pick-to: 6.10
Change-Id: I0867dbbfa611087cd470b821f1f8d7ed74ed0aae
Reviewed-by: Axel Spoerl <[email protected]>

1 files changed, 43 insertions, 57 deletions

diff --git a/src/plugins/sqldrivers/odbc/qsql_odbc.cpp b/src/plugins/sqldrivers/odbc/qsql_odbc.cpp
index 18289f93b54..2c0cfc61923 100644
--- a/src/plugins/sqldrivers/odbc/qsql_odbc.cpp
+++ b/src/plugins/sqldrivers/odbc/qsql_odbc.cpp
@@ -337,7 +337,7 @@ static QSqlError qMakeError(const QString &err,
     return errorFromDiagRecords(err, type, qODBCWarn(p));
 }
 
-static QMetaType qDecodeODBCType(SQLSMALLINT sqltype, bool isSigned = true)
+static QMetaType qDecodeODBCType(SQLSMALLINT sqltype, bool isSigned)
 {
     int type = QMetaType::UnknownType;
     switch (sqltype) {
@@ -520,29 +520,33 @@ static QVariant qGetBinaryData(SQLHANDLE hStmt, int column)
     return fieldVal;
 }
 
-static QVariant qGetIntData(SQLHANDLE hStmt, int column, bool isSigned = true)
-{
-    SQLINTEGER intbuf = 0;
+template <typename T>
+static QVariant qGetIntData(SQLHANDLE hStmt, int column)
+{
+    constexpr auto isSigned = std::is_signed<T>();
+    constexpr auto is16BitType = sizeof(T) == 2;
+    constexpr auto is32BitType = sizeof(T) == 4;
+    constexpr auto is64BitType = sizeof(T) == 8;
+    constexpr auto tgtType =
+        is16BitType ? (isSigned ? SQL_C_SSHORT : SQL_C_USHORT)
+                    : is32BitType ? (isSigned ? SQL_C_SLONG : SQL_C_ULONG)
+                                  : (isSigned ? SQL_C_SBIGINT : SQL_C_UBIGINT);
+    static_assert(is16BitType || is32BitType || is64BitType,
+                  "Can only handle 16, 32 or 64 bit integer");
+    T intbuf = 0;
     SQLLEN lengthIndicator = 0;
-    SQLRETURN r = SQLGetData(hStmt,
-                              column+1,
-                              isSigned ? SQL_C_SLONG : SQL_C_ULONG,
-                              (SQLPOINTER)&intbuf,
-                              sizeof(intbuf),
-                              &lengthIndicator);
+    SQLRETURN r = SQLGetData(hStmt, column + 1, tgtType,
+                            (SQLPOINTER)&intbuf, sizeof(intbuf), &lengthIndicator);
     if (!SQL_SUCCEEDED(r))
         return QVariant();
     if (lengthIndicator == SQL_NULL_DATA)
-        return QVariant(QMetaType::fromType<int>());
-    if (isSigned)
-        return int(intbuf);
-    else
-        return uint(intbuf);
+        return QVariant(QMetaType::fromType<T>());
+    return QVariant::fromValue<T>(intbuf);
 }
 
 static QVariant qGetDoubleData(SQLHANDLE hStmt, int column)
 {
-    SQLDOUBLE dblbuf;
+    SQLDOUBLE dblbuf = 0;
     SQLLEN lengthIndicator = 0;
     SQLRETURN r = SQLGetData(hStmt,
                               column+1,
@@ -550,37 +554,14 @@ static QVariant qGetDoubleData(SQLHANDLE hStmt, int column)
                               (SQLPOINTER) &dblbuf,
                               0,
                               &lengthIndicator);
-    if (!SQL_SUCCEEDED(r)) {
+    if (!SQL_SUCCEEDED(r))
         return QVariant();
-    }
     if (lengthIndicator == SQL_NULL_DATA)
         return QVariant(QMetaType::fromType<double>());
 
     return (double) dblbuf;
 }
 
-
-static QVariant qGetBigIntData(SQLHANDLE hStmt, int column, bool isSigned = true)
-{
-    SQLBIGINT lngbuf = 0;
-    SQLLEN lengthIndicator = 0;
-    SQLRETURN r = SQLGetData(hStmt,
-                              column+1,
-                              isSigned ? SQL_C_SBIGINT : SQL_C_UBIGINT,
-                              (SQLPOINTER) &lngbuf,
-                              sizeof(lngbuf),
-                              &lengthIndicator);
-    if (!SQL_SUCCEEDED(r))
-        return QVariant();
-    if (lengthIndicator == SQL_NULL_DATA)
-        return QVariant(QMetaType::fromType<qlonglong>());
-
-    if (isSigned)
-        return qint64(lngbuf);
-    else
-        return quint64(lngbuf);
-}
-
 static bool isAutoValue(const SQLHANDLE hStmt, int column)
 {
     SQLLEN nNumericAttribute = 0; // Check for auto-increment
@@ -599,13 +580,13 @@ static bool isAutoValue(const SQLHANDLE hStmt, int column)
 static QSqlField qMakeFieldInfo(const SQLHANDLE hStmt, const QODBCDriverPrivate* p)
 {
     QString fname = qGetStringData(hStmt, 3, -1, p->unicode).toString();
-    int type = qGetIntData(hStmt, 4).toInt(); // column type
-    QSqlField f(fname, qDecodeODBCType(type, p));
-    QVariant var = qGetIntData(hStmt, 6);
+    int type = qGetIntData<int>(hStmt, 4).toInt();     // column type
+    QSqlField f(fname, qDecodeODBCType(type, true));    // signed, we don't know better here
+    QVariant var = qGetIntData<int>(hStmt, 6);
     f.setLength(var.isNull() ? -1 : var.toInt()); // column size
-    var = qGetIntData(hStmt, 8).toInt();
+    var = qGetIntData<int>(hStmt, 8).toInt();
     f.setPrecision(var.isNull() ? -1 : var.toInt()); // precision
-    int required = qGetIntData(hStmt, 10).toInt(); // nullable-flag
+    int required = qGetIntData<int>(hStmt, 10).toInt(); // nullable-flag
     // required can be SQL_NO_NULLS, SQL_NULLABLE or SQL_NULLABLE_UNKNOWN
     if (required == SQL_NO_NULLS)
         f.setRequired(true);
@@ -996,9 +977,8 @@ bool QODBCResult::reset (const QString& query)
     SQLNumResultCols(d->hStmt, &count);
     if (count) {
         setSelect(true);
-        for (SQLSMALLINT i = 0; i < count; ++i) {
+        for (SQLSMALLINT i = 0; i < count; ++i)
             d->rInf.append(qMakeFieldInfo(d, i));
-        }
         d->fieldCache.resize(count);
     } else {
         setSelect(false);
@@ -1171,18 +1151,22 @@ QVariant QODBCResult::data(int field)
         const QSqlField info = d->rInf.field(i);
         switch (info.metaType().id()) {
         case QMetaType::LongLong:
-            d->fieldCache[i] = qGetBigIntData(d->hStmt, i);
-        break;
-        case QMetaType::ULongLong:
-            d->fieldCache[i] = qGetBigIntData(d->hStmt, i, false);
+            d->fieldCache[i] = qGetIntData<int64_t>(d->hStmt, i);
             break;
         case QMetaType::Int:
+            d->fieldCache[i] = qGetIntData<int32_t>(d->hStmt, i);
+            break;
         case QMetaType::Short:
-            d->fieldCache[i] = qGetIntData(d->hStmt, i);
+            d->fieldCache[i] = qGetIntData<int16_t>(d->hStmt, i);
+            break;
+        case QMetaType::ULongLong:
+            d->fieldCache[i] = qGetIntData<uint64_t>(d->hStmt, i);
             break;
         case QMetaType::UInt:
+            d->fieldCache[i] = qGetIntData<uint32_t>(d->hStmt, i);
+            break;
         case QMetaType::UShort:
-            d->fieldCache[i] = qGetIntData(d->hStmt, i, false);
+            d->fieldCache[i] = qGetIntData<uint16_t>(d->hStmt, i);
             break;
         case QMetaType::QDate:
             DATE_STRUCT dbuf;
@@ -1233,10 +1217,10 @@ QVariant QODBCResult::data(int field)
         case QMetaType::Double:
             switch(numericalPrecisionPolicy()) {
                 case QSql::LowPrecisionInt32:
-                    d->fieldCache[i] = qGetIntData(d->hStmt, i);
+                    d->fieldCache[i] = qGetIntData<int32_t>(d->hStmt, i);
                     break;
                 case QSql::LowPrecisionInt64:
-                    d->fieldCache[i] = qGetBigIntData(d->hStmt, i);
+                    d->fieldCache[i] = qGetIntData<int64_t>(d->hStmt, i);
                     break;
                 case QSql::LowPrecisionDouble:
                     d->fieldCache[i] = qGetDoubleData(d->hStmt, i);
@@ -1294,6 +1278,9 @@ bool QODBCResult::prepare(const QString& query)
     SQLRETURN r;
 
     d->rInf.clear();
+    d->fieldCache.clear();
+    d->fieldCacheIdx = 0;
+
     if (d->hStmt && d->isStmtHandleValid()) {
         r = SQLFreeHandle(SQL_HANDLE_STMT, d->hStmt);
         if (r != SQL_SUCCESS) {
@@ -1670,9 +1657,8 @@ bool QODBCResult::exec()
     SQLNumResultCols(d->hStmt, &count);
     if (count) {
         setSelect(true);
-        for (SQLSMALLINT i = 0; i < count; ++i) {
+        for (SQLSMALLINT i = 0; i < count; ++i)
             d->rInf.append(qMakeFieldInfo(d, i));
-        }
         d->fieldCache.resize(count);
     } else {
         setSelect(false);