* Added nothrow to the new operator because otherwise the C++ compiler

will not accept if the allocator returns NULL and crashes instead
  (ie. not compiling in tracing would have crashed if some module tried
  to use it).
* Added total entries count to the KDL command output.
* Fixed computing the start index of the KDL command.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@23460 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/private/kernel/tracing.h

@@ -3,6 +3,7 @@
 
 
 #include <SupportDefs.h>
+#include <KernelExport.h>
 
 
 #define ENABLE_TRACING 0
@@ -29,7 +30,29 @@ class TraceEntry : trace_entry {
 
 		void Initialized();
 
-		void* operator new(size_t size);
+		void* operator new(size_t size, const std::nothrow_t&) throw();
+};
+
+class AbstractTraceEntry : public TraceEntry {
+	public:
+		AbstractTraceEntry()
+			:
+			fThread(find_thread(NULL)),
+			fTime(system_time())
+		{
+		}
+
+		virtual void Dump()
+		{
+			kprintf("[%6ld] %Ld: ", fThread, fTime);
+		}
+
+		thread_id Thread() const { return fThread; }
+		bigtime_t Time() const { return fTime; }
+
+	protected:
+		thread_id	fThread;
+		bigtime_t	fTime;
 };
 
 #endif	// __cplusplus

src/system/kernel/debug/tracing.cpp

@@ -101,7 +101,7 @@ TraceEntry::Initialized()
 
 
 void*
-TraceEntry::operator new(size_t size) throw()
+TraceEntry::operator new(size_t size, const std::nothrow_t&) throw()
 {
 #if ENABLE_TRACING
 	if (sBuffer == NULL)
@@ -143,17 +143,19 @@ int
 dump_tracing(int argc, char** argv)
 {
 	int32 count = 30;
+	if (argc == 2)
+		count = strtol(argv[1], NULL, 0);
+
 	int32 start = sEntries - count;
 
-	if (argc == 2) {
+	if (argc == 3) {
-		count = strtol(argv[1], NULL, 0);
-	} else if (argc == 3) {
 		start = strtol(argv[1], NULL, 0);
 		count = strtol(argv[2], NULL, 0);
 	} else if (argc > 3) {
 		kprintf("usage: %s [start] [count]\n", argv[0]);
 		return 0;
 	}
+	// TODO: add pattern matching mechanism for the class name
 
 	if (start < 0)
 		start = 0;
@@ -173,6 +175,7 @@ dump_tracing(int argc, char** argv)
 			kprintf("** uninitialized entry **\n");
 	}
 
+	kprintf("%ld of %ld entries.\n", count, sEntries);
 	return 0;
 }