SQL/ODBC: Return all native error codes

ODBC can (similar to DB2) return more than one native error code for an
error but only the last one was recorded which may made the error
diagnostic more complicated. Therefore return a concatenated list of
native error codes the way it's done for DB2.

[ChangeLog][SQL][ODBC] QSqlError::errorCode() might return a semicolon
separated list of native error codes.

Fixes: QTBUG-45087
Change-Id: I70d02adeb33e72897f13e0c72fbbd2c60f307e2f
Reviewed-by: Volker Hilsheimer <volker.hilsheimer@qt.io>

1 files changed, 76 insertions, 78 deletions

diff --git a/src/plugins/sqldrivers/odbc/qsql_odbc.cpp b/src/plugins/sqldrivers/odbc/qsql_odbc.cpp
index 2d367afa7e..c2252c3f77 100644
--- a/src/plugins/sqldrivers/odbc/qsql_odbc.cpp
+++ b/src/plugins/sqldrivers/odbc/qsql_odbc.cpp
@@ -198,118 +198,115 @@ void QODBCResultPrivate::updateStmtHandleState()
     disconnectCount = drv_d_func() ? drv_d_func()->disconnectCount : 0;
 }
 
-static QString qWarnODBCHandle(int handleType, SQLHANDLE handle, int *nativeCode = nullptr)
+struct DiagRecord
 {
-    SQLINTEGER nativeCode_ = 0;
+    QString description;
+    QString sqlState;
+    QString errorCode;
+};
+static QList<DiagRecord> qWarnODBCHandle(int handleType, SQLHANDLE handle)
+{
+    SQLINTEGER nativeCode = 0;
     SQLSMALLINT msgLen = 0;
+    SQLSMALLINT i = 1;
     SQLRETURN r = SQL_NO_DATA;
-    SQLTCHAR state_[SQL_SQLSTATE_SIZE+1];
-    QVarLengthArray<SQLTCHAR, SQL_MAX_MESSAGE_LENGTH> description_(SQL_MAX_MESSAGE_LENGTH);
-    QString result;
-    int i = 1;
+    QVarLengthArray<SQLTCHAR, SQL_SQLSTATE_SIZE + 1> state(SQL_SQLSTATE_SIZE + 1);
+    QVarLengthArray<SQLTCHAR, SQL_MAX_MESSAGE_LENGTH + 1> description(SQL_MAX_MESSAGE_LENGTH + 1);
+    QList<DiagRecord> result;
 
-    description_[0] = 0;
+    if (!handle)
+        return result;
     do {
         r = SQLGetDiagRec(handleType,
                           handle,
                           i,
-                          state_,
-                          &nativeCode_,
-                          0,
-                          0,
+                          state.data(),
+                          &nativeCode,
+                          description.data(),
+                          description.size(),
                           &msgLen);
-        if ((r == SQL_SUCCESS || r == SQL_SUCCESS_WITH_INFO) && msgLen > 0)
-            description_.resize(msgLen+1);
-        r = SQLGetDiagRec(handleType,
-                            handle,
-                            i,
-                            state_,
-                            &nativeCode_,
-                            description_.data(),
-                            description_.size(),
-                            &msgLen);
+        if (msgLen >= description.size()) {
+            description.resize(msgLen + 1); // incl. \0 termination
+            continue;
+        }
         if (r == SQL_SUCCESS || r == SQL_SUCCESS_WITH_INFO) {
-            if (nativeCode)
-                *nativeCode = nativeCode_;
-            const QString tmpstore = fromSQLTCHAR(description_, msgLen);
-            if (result != tmpstore) {
-                if (!result.isEmpty())
-                    result += u' ';
-                result += tmpstore;
-            }
+            result.push_back({fromSQLTCHAR(description, msgLen),
+                              fromSQLTCHAR(state),
+                              QString::number(nativeCode)});
         } else if (r == SQL_ERROR || r == SQL_INVALID_HANDLE) {
-            return result;
+            break;
         }
         ++i;
     } while (r != SQL_NO_DATA);
     return result;
 }
 
-static QString qODBCWarn(const SQLHANDLE hStmt, const SQLHANDLE envHandle = 0,
-                         const SQLHANDLE pDbC = 0, int *nativeCode = nullptr)
+static QList<DiagRecord> qODBCWarn(const SQLHANDLE hStmt,
+                                   const SQLHANDLE envHandle = nullptr,
+                                   const SQLHANDLE pDbC = nullptr)
 {
-    QString result;
-    if (envHandle)
-        result += qWarnODBCHandle(SQL_HANDLE_ENV, envHandle, nativeCode);
-    if (pDbC) {
-        const QString dMessage = qWarnODBCHandle(SQL_HANDLE_DBC, pDbC, nativeCode);
-        if (!dMessage.isEmpty()) {
-            if (!result.isEmpty())
-                result += u' ';
-            result += dMessage;
-        }
-    }
-    if (hStmt) {
-        const QString hMessage = qWarnODBCHandle(SQL_HANDLE_STMT, hStmt, nativeCode);
-        if (!hMessage.isEmpty()) {
-            if (!result.isEmpty())
-                result += u' ';
-            result += hMessage;
-        }
-    }
+    QList<DiagRecord> result;
+    result.append(qWarnODBCHandle(SQL_HANDLE_ENV, envHandle));
+    result.append(qWarnODBCHandle(SQL_HANDLE_DBC, pDbC));
+    result.append(qWarnODBCHandle(SQL_HANDLE_STMT, hStmt));
     return result;
 }
 
-static QString qODBCWarn(const QODBCResultPrivate* odbc, int *nativeCode = nullptr)
+static QList<DiagRecord> qODBCWarn(const QODBCResultPrivate *odbc)
 {
-    return qODBCWarn(odbc->hStmt, odbc->dpEnv(), odbc->dpDbc(), nativeCode);
+    return qODBCWarn(odbc->hStmt, odbc->dpEnv(), odbc->dpDbc());
 }
 
-static QString qODBCWarn(const QODBCDriverPrivate* odbc, int *nativeCode = nullptr)
+static QList<DiagRecord> qODBCWarn(const QODBCDriverPrivate *odbc)
 {
-    return qODBCWarn(0, odbc->hEnv, odbc->hDbc, nativeCode);
+    return qODBCWarn(nullptr, odbc->hEnv, odbc->hDbc);
+}
+
+static DiagRecord combineRecords(const QList<DiagRecord> &records)
+{
+    const auto add = [](const DiagRecord &a, const DiagRecord &b) {
+        return DiagRecord{a.description + u' ' + b.description,
+                          a.sqlState + u';' + b.sqlState,
+                          a.errorCode + u';' + b.errorCode};
+    };
+    return std::accumulate(std::next(records.begin()), records.end(), records.front(), add);
 }
 
-static void qSqlWarning(const QString& message, const QODBCResultPrivate* odbc)
+static QSqlError errorFromDiagRecords(const QString &err,
+                                      QSqlError::ErrorType type,
+                                      const QList<DiagRecord> &records)
 {
-    qWarning() << message << "\tError:" << qODBCWarn(odbc);
+    if (records.empty())
+        return QSqlError("QODBC: unknown error"_L1, {}, type, {});
+    const auto combined = combineRecords(records);
+    return QSqlError("QODBC: "_L1 + err, combined.description + ", "_L1 + combined.sqlState, type,
+                     combined.errorCode);
 }
 
-static void qSqlWarning(const QString &message, const QODBCDriverPrivate *odbc)
+static QString errorStringFromDiagRecords(const QList<DiagRecord>& records)
 {
-    qWarning() << message << "\tError:" << qODBCWarn(odbc);
+    const auto combined = combineRecords(records);
+    return combined.description;
 }
 
-static void qSqlWarning(const QString &message, const SQLHANDLE hStmt)
+template<class T>
+static void qSqlWarning(const QString &message, T &&val)
 {
-    qWarning() << message << "\tError:" << qODBCWarn(hStmt);
+    qWarning() << message << "\tError:" << errorStringFromDiagRecords(qODBCWarn(val));
 }
 
-static QSqlError qMakeError(const QString& err, QSqlError::ErrorType type, const QODBCResultPrivate* p)
+static QSqlError qMakeError(const QString &err,
+                            QSqlError::ErrorType type,
+                            const QODBCResultPrivate *p)
 {
-    int nativeCode = -1;
-    QString message = qODBCWarn(p, &nativeCode);
-    return QSqlError("QODBC: "_L1 + err, message, type,
-                     nativeCode != -1 ? QString::number(nativeCode) : QString());
+    return errorFromDiagRecords(err, type, qODBCWarn(p));
 }
 
-static QSqlError qMakeError(const QString& err, QSqlError::ErrorType type,
-                            const QODBCDriverPrivate* p)
+static QSqlError qMakeError(const QString &err,
+                            QSqlError::ErrorType type,
+                            const QODBCDriverPrivate *p)
 {
-    int nativeCode = -1;
-    QString message = qODBCWarn(p, &nativeCode);
-    return QSqlError("QODBC: "_L1 + err, message, type,
-                     nativeCode != -1 ? QString::number(nativeCode) : QString());
+    return errorFromDiagRecords(err, type, qODBCWarn(p));
 }
 
 static QMetaType qDecodeODBCType(SQLSMALLINT sqltype, bool isSigned = true)
@@ -419,7 +416,7 @@ static QVariant getStringDataImpl(SQLHANDLE hStmt, SQLUSMALLINT column, qsizetyp
         } else if (r == SQL_NO_DATA) {
             break;
         } else {
-            qWarning() << "qGetStringData: Error while fetching data (" << qWarnODBCHandle(SQL_HANDLE_STMT, hStmt) << ')';
+            qSqlWarning("qGetStringData: Error while fetching data:"_L1, hStmt);
             return {};
         }
     }
@@ -1618,7 +1615,7 @@ bool QODBCResult::exec()
                 break; }
         }
         if (r != SQL_SUCCESS) {
-            qWarning() << "QODBCResult::exec: unable to bind variable:" << qODBCWarn(d);
+            qSqlWarning("QODBCResult::exec: unable to bind variable:"_L1, d);
             setLastError(qMakeError(QCoreApplication::translate("QODBCResult",
                          "Unable to bind variable"), QSqlError::StatementError, d));
             return false;
@@ -1626,7 +1623,7 @@ bool QODBCResult::exec()
     }
     r = SQLExecute(d->hStmt);
     if (r != SQL_SUCCESS && r != SQL_SUCCESS_WITH_INFO && r != SQL_NO_DATA) {
-        qWarning() << "QODBCResult::exec: Unable to execute statement:" << qODBCWarn(d);
+        qSqlWarning("QODBCResult::exec: Unable to execute statement:"_L1, d);
         setLastError(qMakeError(QCoreApplication::translate("QODBCResult",
                      "Unable to execute statement"), QSqlError::StatementError, d));
         return false;
@@ -1766,8 +1763,7 @@ bool QODBCResult::nextResult()
     SQLRETURN r = SQLMoreResults(d->hStmt);
     if (r != SQL_SUCCESS) {
         if (r == SQL_SUCCESS_WITH_INFO) {
-            int nativeCode = -1;
-            QString message = qODBCWarn(d, &nativeCode);
+            QString message = errorStringFromDiagRecords(qODBCWarn(d));
             qWarning() << "QODBCResult::nextResult():" << message;
         } else {
             if (r != SQL_NO_DATA)
@@ -2344,7 +2340,9 @@ QStringList QODBCDriver::tables(QSql::TableType type) const
         r = SQLFetch(hStmt);
 
     if (r != SQL_SUCCESS && r != SQL_SUCCESS_WITH_INFO && r != SQL_NO_DATA) {
-        qWarning() << "QODBCDriver::tables failed to retrieve table/view list: (" << r << "," << qWarnODBCHandle(SQL_HANDLE_STMT, hStmt) << ")";
+        qSqlWarning("QODBCDriver::tables failed to retrieve table/view list: ("_L1
+                            + QString::number(r) + u':',
+                    hStmt);
         return QStringList();
     }