First incarnation of the logging code

logv2.h

@@ -0,0 +1,60 @@
+/*
+  This is a reimplementation of SICS logging. The aim is to 
+  merge all the different logs within SICS to the new logging 
+  system
+
+  COPYRIGHT: see file COPYRIGHT
+
+  Mark Koennecke, February 2016
+ */
+
+#ifndef __LOGV2
+#define __LOGV2
+#include <stdarg.h>
+
+#define FATAL   1
+#define ERROR   2
+#define WARN    3
+#define INFO    4
+#define VERBOSE 5
+#define DEBUG   6
+#define INVALID 7 /* internal olny, do not use, means invalid severity passed */
+
+/* write a log message
+ * \param severity The message severity. Must be one of the defines given above
+ * \param subsystem The subsystem reporting the log messages
+ * \param format The format string for the message
+ * \param ... The data to format
+ */
+void Log(unsigned int severity, const char *subsystem,const char *format,...); 
+
+/* The callback functio which is called by the logging system on log events
+ * \param severity The message severity
+ * \param timeStamp The time stamp of the log message
+ * \param subsystem The subsystem of the log message
+ * \param message The log message
+ * \param userData A pointer to a user define ddata structure passed through 
+ *        transparantly from RegisterLogCallback
+*/
+
+/*
+At this time LogCallback do not do any filtering. Thus, they see every message.
+The idea is that suitable filtering functions ought to be implemented as helper 
+functions once the exact usage of the log \callbacks becomes clearer. 
+ */
+
+typedef void (*LogCallback)(unsigned int severity, const char *timeStamp, 
+			    const char *subsystem, 
+			    const char *message, void *userData);
+
+/* register a LogCallback
+ * \param func The function to call whena suitable log message has been found
+ * \param userData A pointer to user defined data which is passed through to the 
+ *  callback function. The log system does not free that pointer; this is up to the caller
+ * \return An callback ID which can be used for RemoveLogCallback
+ */  
+
+void RegisterLogCallback(LogCallback func, void *userData);
+void RemoveLogCallback(LogCallback func);
+
+#endif