Add payloads, bitmaps to trace API

This is a proposed adjustment to the trace APIs.  This makes the
trace levels into a bitmask so that they can be selectively enabled
and adds a callback-level payload, plus a message-level payload.

This makes it easier for me to a GIT_TRACE_PERF callbacks that
are simply bypassed if the PERF level is not set.

1 files changed, 11 insertions, 8 deletions

diff --git a/src/trace.h b/src/trace.h
index 4d4e3bf53..b35e3808f 100644
--- a/src/trace.h
+++ b/src/trace.h
@@ -15,13 +15,16 @@
 struct git_trace_data {
 	git_trace_level_t level;
 	git_trace_callback callback;
+	void *callback_payload;
 };
 
 extern struct git_trace_data git_trace__data;
 
 GIT_INLINE(void) git_trace__write_fmt(
 	git_trace_level_t level,
-	const char *fmt, ...)
+	void *message_payload,
+	const char *fmt,
+	...)
 {
 	git_trace_callback callback = git_trace__data.callback;
 	git_buf message = GIT_BUF_INIT;
@@ -31,18 +34,18 @@ GIT_INLINE(void) git_trace__write_fmt(
 	git_buf_vprintf(&message, fmt, ap);
 	va_end(ap);
 
-	callback(level, git_buf_cstr(&message));
+	callback(
+		level, git_trace__data.callback_payload, message_payload,
+		git_buf_cstr(&message));
 
 	git_buf_free(&message);
 }
 
 #define git_trace_level()		(git_trace__data.level)
-#define git_trace(l, ...)		{ \
-									if (git_trace__data.level >= l && \
-										git_trace__data.callback != NULL) { \
-										git_trace__write_fmt(l, __VA_ARGS__); \
-									} \
-								}
+#define git_trace(l, p, ...)	do { \
+	if ((git_trace__data.level & (l)) != 0 && git_trace__data.callback) { \
+		git_trace__write_fmt((l), (p), __VA_ARGS__); \
+	} } while (0)
 
 #else