initial commit

+io/private/ptycho_reader/debug_helper.h

@@ -0,0 +1,60 @@
+/*!
+ * \file
+ * Helper code for debug handling
+ */
+
+#ifndef DEBUG_HELPER
+#define DEBUG_HELPER
+
+/*!
+ * \brief Debug functionality
+ *
+ * The environment variable PTYCHO_READ_DEBUG gives the name of the debug log file
+ */
+namespace debug {
+    extern std::unique_ptr<std::ofstream> out; //!< pointer to debug file
+
+    /*!
+     * \brief Check debug output stream
+     * \return true if stream is operational, otherwise false
+     */
+    inline bool check_out()
+    {
+        if (out.get())
+            return out.get()->good();
+        return false;
+    }
+
+    /*!
+     * \brief Initialize debug output stream
+     */
+    inline void debug_init()
+    {
+        out.reset(nullptr);
+        const char *fname = std::getenv("PTYCHO_READ_DEBUG");
+        if (fname) {
+            out.reset(new std::ofstream(fname, std::ios::app));
+            if (! out.get()->good())
+                out.reset(nullptr);
+        }
+    }
+}
+
+/*!
+ * \brief Initialize debug stream
+ */
+#define DEBUG_INIT debug::debug_init()
+
+/*!
+ * \brief Start debug code block
+ * Only access the debug stream inside such a block
+ */
+#define DEBUG if (debug::check_out())
+
+/*!
+ * \brief Access debug output stream
+ * \return debug output stream reference
+ */
+#define OUT (*debug::out.get())
+
+#endif