ax25ipd: Make LOGx() macros bulletproof.

The LOGL1..LOGL4 macros were defined like:

Now consider an invocation like:

	if (condition)
		LOGL1(...);
	else
		something_different();

CPP will expand this like:

	if (condition)
		if (loglevel>0)
			syslog(LOG_DAEMON | LOG_WARNING, ...);
		else
			something_different();

That is the else would now be considered associated with the wrong if.

Macro arguments may also not have been evaluated on every invocation
making the use of these function-like looking macros not function like.

For example:

	LOGL1("%d", i++);

would be expanded to

	if (loglevel>0)
		syslog(LOG_DAEMON | LOG_WARNING, i++);

That is depending on the value of loglevel i++ would only be incremented if
syslog was actually being called.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 6 insertions, 4 deletions

diff --git a/ax25ipd/ax25ipd.h b/ax25ipd/ax25ipd.h
index 06efd58..b088247 100644
--- a/ax25ipd/ax25ipd.h
+++ b/ax25ipd/ax25ipd.h
@@ -111,10 +111,12 @@ struct {
 
 #define MAX_FRAME 2048
 
-#define LOGL1(arg...) if(loglevel>0)syslog(LOG_DAEMON | LOG_WARNING, ##arg)
-#define LOGL2(arg...) if(loglevel>1)syslog(LOG_DAEMON | LOG_WARNING, ##arg)
-#define LOGL3(arg...) if(loglevel>2)syslog(LOG_DAEMON | LOG_WARNING, ##arg)
-#define LOGL4(arg...) if(loglevel>3)(void)syslog(LOG_DAEMON | LOG_DEBUG, ##arg)
+extern void LOGLn(int level, const char *str, ...);
+
+#define LOGL1(arg...) LOGLn(1, ##arg)
+#define LOGL2(arg...) LOGLn(2, ##arg)
+#define LOGL3(arg...) LOGLn(3, ##arg)
+#define LOGL4(arg...) LOGLn(4, ##arg)
 
 #define	AXRT_BCAST	1
 #define	AXRT_DEFAULT	2