trace: remove trace key normalization

Gennady Kupava · gitster · commit 406102a73114 · 2017-11-27T10:19:08.000+09:00
Trace key normalization is not used, not strictly necessary,
complicates the code and would negatively affect compilation speed if
moved to header.

New trace_default_key key or existing separate marco could be used
instead of passing NULL as a key.

Signed-off-by: Gennady Kupava &lt;gkupava@bloomberg.net&gt;
Signed-off-by: Junio C Hamano &lt;gitster@pobox.com&gt;
diff --git a/trace.c b/trace.c
@@ -24,26 +24,13 @@
 #include "cache.h"
 #include "quote.h"
 
-/*
- * "Normalize" a key argument by converting NULL to our trace_default,
- * and otherwise passing through the value. All caller-facing functions
- * should normalize their inputs in this way, though most get it
- * for free by calling get_trace_fd() (directly or indirectly).
- */
-static void normalize_trace_key(struct trace_key **key)
-{
-	static struct trace_key trace_default = { "GIT_TRACE" };
-	if (!*key)
-		*key = &trace_default;
-}
+struct trace_key trace_default_key = { "GIT_TRACE", 0, 0, 0 };
 
 /* Get a trace file descriptor from "key" env variable. */
 static int get_trace_fd(struct trace_key *key)
 {
 	const char *trace;
 
-	normalize_trace_key(&key);
-
 	/* don't open twice */
 	if (key->initialized)
 		return key->fd;
@@ -81,8 +68,6 @@ static int get_trace_fd(struct trace_key *key)
 
 void trace_disable(struct trace_key *key)
 {
-	normalize_trace_key(&key);
-
 	if (key->need_close)
 		close(key->fd);
 	key->fd = 0;
@@ -128,7 +113,6 @@ static int prepare_trace_line(const char *file, int line,
 static void trace_write(struct trace_key *key, const void *buf, unsigned len)
 {
 	if (write_in_full(get_trace_fd(key), buf, len) < 0) {
-		normalize_trace_key(&key);
 		warning("unable to write trace for %s: %s",
 			key->key, strerror(errno));
 		trace_disable(key);
@@ -167,13 +151,13 @@ static void trace_argv_vprintf_fl(const char *file, int line,
 {
 	struct strbuf buf = STRBUF_INIT;
 
-	if (!prepare_trace_line(file, line, NULL, &buf))
+	if (!prepare_trace_line(file, line, &trace_default_key, &buf))
 		return;
 
 	strbuf_vaddf(&buf, format, ap);
 
 	sq_quote_argv(&buf, argv, 0);
-	print_trace_line(NULL, &buf);
+	print_trace_line(&trace_default_key, &buf);
 }
 
 void trace_strbuf_fl(const char *file, int line, struct trace_key *key,
@@ -215,7 +199,7 @@ void trace_printf(const char *format, ...)
 {
 	va_list ap;
 	va_start(ap, format);
-	trace_vprintf_fl(NULL, 0, NULL, format, ap);
+	trace_vprintf_fl(NULL, 0, &trace_default_key, format, ap);
 	va_end(ap);
 }
 
diff --git a/trace.h b/trace.h
@@ -11,6 +11,8 @@ struct trace_key {
 	unsigned int  need_close : 1;
 };
 
+extern struct trace_key trace_default_key;
+
 #define TRACE_KEY_INIT(name) { "GIT_TRACE_" #name, 0, 0, 0 }
 
 extern void trace_repo_setup(const char *prefix);
@@ -78,7 +80,7 @@ extern void trace_performance_since(uint64_t start, const char *format, ...);
  */
 
 #define trace_printf(...) \
-	trace_printf_key_fl(TRACE_CONTEXT, __LINE__, NULL, __VA_ARGS__)
+	trace_printf_key_fl(TRACE_CONTEXT, __LINE__, &trace_default_key, __VA_ARGS__)
 
 #define trace_printf_key(key, ...) \
 	trace_printf_key_fl(TRACE_CONTEXT, __LINE__, key, __VA_ARGS__)
