core: updated dprint api to enable support for debug level per module

- a callback can be registered to return the log level based on module
  name

dprint.c

@@ -115,12 +115,29 @@ int log_facility_fixup(void *handle, str *gname, str *name, void **val)
 
 /* the local debug log level */
 static int _local_debug_level = UNSET_LOCAL_DEBUG_LEVEL;
+/* callback to get per module debug level */
+static get_module_debug_level_f _module_debug_level = NULL;
+
+/**
+ * @brief set callback function for per module debug level
+ */
+void set_module_debug_level_cb(get_module_debug_level_f f)
+{
+	_module_debug_level = f;
+}
 
 /**
  * @brief return the log level - the local one if it set,
  *   otherwise the global value
  */
-int get_debug_level(void) {
+int get_debug_level(char *mname, int mnlen) {
+	int mlevel = L_DBG;
+	/*important -- no LOGs inside, because it will loop */
+	if(unlikely(_module_debug_level!=NULL && mnlen>0)) {
+		if(_module_debug_level(mname, mnlen, &mlevel)==0) {
+			return mlevel;
+		}
+	}
 	return (_local_debug_level != UNSET_LOCAL_DEBUG_LEVEL) ?
 				_local_debug_level : cfg_get(core, core_cfg, debug);
 }

dprint.h

@@ -59,8 +59,10 @@
 #ifdef NO_DEBUG
 #	ifdef MOD_NAME
 #		define LOC_INFO		MOD_NAME ": "
+#		define LOG_MNAME	MOD_NAME
 #	else
 #		define LOC_INFO		"<core>: "
+#		define LOG_MNAME	"core"
 #	endif
 #else
 #	define XCT2STR(i) #i
@@ -68,8 +70,10 @@
 #
 #	ifdef MOD_NAME
 #		define LOC_INFO		MOD_NAME " [" __FILE__ ":" CT2STR(__LINE__) "]: "
+#		define LOG_MNAME	MOD_NAME
 #	else
 #		define LOC_INFO		"<core> [" __FILE__ ":" CT2STR(__LINE__) "]: "
+#		define LOG_MNAME	"core"
 #	endif
 #
 #	ifdef NO_LOG
@@ -77,6 +81,7 @@
 #	endif
 #endif /* NO_DEBUG */
 
+#define LOG_MNAME_LEN		(sizeof(LOG_MNAME)-1)
 
 /*
  * Log levels
@@ -121,11 +126,13 @@ struct log_level_info {
 };
 
 /** @brief per process debug level handling */
-int get_debug_level(void);
+int get_debug_level(char *mname, int mnlen);
 void set_local_debug_level(int level);
 void reset_local_debug_level(void);
+typedef int (*get_module_debug_level_f)(char *mname, int mnlen, int *mlevel);
+void set_module_debug_level_cb(get_module_debug_level_f f);
 
-#define is_printable(level) (get_debug_level()>=(level))
+#define is_printable(level) (get_debug_level(LOG_MNAME, LOG_MNAME_LEN)>=(level))
 extern struct log_level_info log_level_info[];
 extern char *log_name;
 
@@ -179,7 +186,7 @@ void dprint_term_color(char f, char b, str *obuf);
 #	ifdef __SUNPRO_C
 #		define LOG_(facility, level, prefix, fmt, ...) \
 			do { \
-				if (unlikely(get_debuglevel() >= (level) && \
+				if (unlikely(get_debug_level(LOG_MNAME, LOG_MNAME_LEN) >= (level) && \
 						DPRINT_NON_CRIT)) { \
 					DPRINT_CRIT_ENTER; \
 					if (likely(((level) >= L_ALERT) && ((level) <= L_DBG))){ \
@@ -245,7 +252,7 @@ void dprint_term_color(char f, char b, str *obuf);
 #	else /* ! __SUNPRO_C */
 #		define LOG_(facility, level, prefix, fmt, args...) \
 			do { \
-				if (get_debug_level() >= (level) && \
+				if (get_debug_level(LOG_MNAME, LOG_MNAME_LEN) >= (level) && \
 						DPRINT_NON_CRIT) { \
 					DPRINT_CRIT_ENTER; \
 					if (likely(((level) >= L_ALERT) && ((level) <= L_DBG))){ \