MXS-1461 Add TempFile

Class for creating a temporary file.

server/modules/filter/dbfwfilter/test/tempfile.cc

@@ -0,0 +1,51 @@
+/*
+ * Copyright (c) 2016 MariaDB Corporation Ab
+ *
+ * Use of this software is governed by the Business Source License included
+ * in the LICENSE.TXT file and at www.mariadb.com/bsl11.
+ *
+ * Change Date: 2020-01-01
+ *
+ * On the date above, in accordance with the Business Source License, use
+ * of this software will be governed by version 2 or later of the General
+ * Public License.
+ */
+
+#include "tempfile.hh"
+#include <string.h>
+#include <unistd.h>
+#include <maxscale/debug.h>
+
+namespace
+{
+
+static char NAME_TEMPLATE[] = "/tmp/XXXXXX";
+
+}
+
+TempFile::TempFile()
+    : m_fd(-1)
+    , m_name(NAME_TEMPLATE)
+{
+    m_fd = mkstemp((char*)m_name.c_str());
+    ss_dassert(m_fd != -1);
+}
+
+TempFile::~TempFile()
+{
+    int rc = unlink(m_name.c_str());
+    ss_dassert(rc != -1);
+    close(m_fd);
+}
+
+void TempFile::write(const void* pData, size_t count)
+{
+    int rc = ::write(m_fd, pData, count);
+    ss_dassert(rc != -1);
+    ss_dassert((size_t)rc == count);
+}
+
+void TempFile::write(const char* zData)
+{
+    write(zData, strlen(zData));
+}

server/modules/filter/dbfwfilter/test/tempfile.hh

@@ -0,0 +1,69 @@
+#pragma once
+/*
+ * Copyright (c) 2016 MariaDB Corporation Ab
+ *
+ * Use of this software is governed by the Business Source License included
+ * in the LICENSE.TXT file and at www.mariadb.com/bsl11.
+ *
+ * Change Date: 2020-01-01
+ *
+ * On the date above, in accordance with the Business Source License, use
+ * of this software will be governed by version 2 or later of the General
+ * Public License.
+ */
+
+#include <string>
+
+/**
+ * TempFile is a class using which a temporary file can be created and
+ * written to.
+ */
+class TempFile
+{
+    TempFile(const TempFile&);
+    TempFile& operator = (const TempFile&);
+
+public:
+    /**
+     * Constructor
+     *
+     * Create temporary file in /tmp
+     */
+    TempFile();
+
+    /**
+     * Destructor
+     *
+     * Close and unlink file.
+     */
+    ~TempFile();
+
+    /**
+     * The name of the created temporary file.
+     *
+     * @return The name of the file.
+     */
+    std::string name() const
+    {
+        return m_name;
+    }
+
+    /**
+     * Write data to the file.
+     *
+     * @param pData  Pointer to data.
+     * @param count  The number of bytes to write.
+     */
+    void write(const void* pData, size_t count);
+
+    /**
+     * Write data to the file.
+     *
+     * @param zData  Null terminated buffer to write.
+     */
+    void write(const char* zData);
+
+private:
+    int         m_fd;
+    std::string m_name;
+};