Add event_enable_debug_logging() to control use of debug logs

Previously, debug logs were turned on if you built with -DUSE_DEBUG
and off otherwise.  This make builds with -DUSE_DEBUG hideously slow
and other builds unable to get debug logs.

This is based off a patch by Ralph Castain from October.  It tries a
little harder to avoid needless function calls, it doesn't require
stdbool, and makes the controlling parameter a mask rather than a
boolean so that we can later support enabling only the debugging
messages for the parts of Libevent you're trying to debug.

1 files changed, 19 insertions, 0 deletions

diff --git a/log.c b/log.c
index f0cd4320..79eaae71 100644
--- a/log.c
+++ b/log.c
@@ -63,6 +63,25 @@ static void event_exit(int errcode) EV_NORETURN;
 
 static event_fatal_cb fatal_fn = NULL;
 
+#ifdef EVENT_DEBUG_LOGGING_ENABLED
+#ifdef USE_DEBUG
+#define DEFAULT_MASK EVENT_DBG_ALL
+#else
+#define DEFAULT_MASK 0
+#endif
+
+#ifdef USE_GLOBAL_FOR_DEBUG_LOGGING
+ev_uint32_t _event_debug_logging_mask = DEFAULT_MASK;
+#else
+static ev_uint32_t _event_debug_logging_mask = DEFAULT_MASK;
+ev_uint32_t
+_event_debug_get_logging_mask(void)
+{
+	return _event_debug_logging_mask;
+}
+#endif
+#endif /* EVENT_DEBUG_LOGGING_ENABLED */
+
 void
 event_set_fatal_callback(event_fatal_cb cb)
 {