Changeset 2c11c1 for src/Patterns/Observer/ObserverLog.cpp

Timestamp:

Dec 13, 2011, 10:45:00 AM (14 years ago)

Author:

Frederik Heber <heber@…>

Children:

d85532

Parents:

40f2e6

git-author:

Frederik Heber <heber@…> (12/02/11 13:05:49)

git-committer:

Frederik Heber <heber@…> (12/13/11 10:45:00)

Message:

Modified ObserverLog: Singleton and both output to screen and internal Log.

• ObserverLog can now either be printed concurrently or later requested as string (e.g. on exit as has been done before). This should ease debugging Observer code.
• enable/disableLogging() (dis)activate printing to screen.
• ObserverLog is now a true singleton.

Details:

• Implemented helper class ObserverLog::Log which is returned as boost::shared_ptr on addMessage() and can be streamed to.
• On dstor the logged message is appended with endl, placed into ObserverLog's internal log and printed on screen if enableLogging().
• NOTE: streaming std::endl is not working, and not necessary.

File:

• src/Patterns/Observer/ObserverLog.cpp (modified) (2 diffs)

src/Patterns/Observer/ObserverLog.cpp

@@ -20 +20 @@
 #include "MemDebug.hpp"
 
+#include <fstream>
+#include <iostream>
+#include <sstream>
+
 #include "ObserverLog.hpp"
+#include "Singleton_impl.hpp"
 
+std::ostream* ObserverLog::nullstream = NULL;
+std::ostream* ObserverLog::outstream = NULL;
 
-ObserverLog::ObserverLog() :
-  count (0)
+ObserverLog::ObserverLog()
+{
+  nullstream = new std::ofstream("/dev/null");
+  outstream = nullstream;
+}
+
+ObserverLog::~ObserverLog()
+{
+  outstream = NULL;
+  delete nullstream;
+}
+
+/** Constructor of class Log.
+ *
+ * Log is just a tiny helper to bring the log message to screen and to the
+ * ObserverLog's log.
+ *
+ * @param _callback_ref
+ */
+ObserverLog::Log::Log(ObserverLog *_callback_ref) :
+    callback_ref(_callback_ref)
 {}
 
-ObserverLog::~ObserverLog(){}
+/** Destructor of class Log.
+ *
+ * Prints to both ObserverLog::log and to ObserverLog::outstream.
+ *
+ */
+ObserverLog::Log::~Log()
+{
+  callback_ref->log << log.str() << std::endl;
+  *callback_ref->outstream << log.str() << std::endl;
 
-std::string ObserverLog::getLog(){return log.str();}
+  callback_ref = NULL;
+}
+
+void ObserverLog::disableLogging()
+{
+  outstream = nullstream;
+}
+
+void ObserverLog::enableLogging()
+{
+  outstream = &std::cout;
+}
+
+std::string ObserverLog::getLog() { return log.str(); }
 
 std::string ObserverLog::getName(void* obj){
@@ -57 +104 @@
 }
 
-std::stringstream &ObserverLog::addMessage(int depth){
+/** Obtain Log reference to place another message (line) in log.
+ *
+ * \warning Don't append std::endl to the message, won't work and is done
+ * automatically.
+ *
+ * @param depth depth (indenting) of the message
+ * @return ref to Log class which can be ostreamed to
+ */
+boost::shared_ptr<ObserverLog::Log> ObserverLog::addMessage(int depth){
+  boost::shared_ptr<ObserverLog::Log> L(new Log(this));
   for(int i=depth;i--;)
-    log << "  ";
-  return log;
+    L->log << "  ";
+  return L;
 }
 
-// The log needs to exist fairly early, so we make it construct on first use,
-// and never destroy it
-ObserverLog &observerLog(){
-  // yes, this memory is never freed... we need it around for the whole programm,
-  // so no freeing is possible
-  static ObserverLog *theLog = Memory::ignore(new ObserverLog());
-  return *theLog;
+ObserverLog &observerLog()
+{
+  return ObserverLog::getInstance();
 }
 
+CONSTRUCT_SINGLETON(ObserverLog)