perf tools: Create for_each_event macro for tracepoints iteration

Similar to for_each_subsystem and for_each_event in util/parse-events.c,
add new macro 'for_each_event' for easy iteration over the tracepoints
in order to be more compact and readable.
Signed-off-by: Taeung Song <treeze.taeung@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/1485862711-20216-2-git-send-email-treeze.taeung@gmail.com
[ Slight change to keep existing style for checking strcmp() return ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/trace-event-info.c

@@ -170,6 +170,12 @@ static bool name_in_tp_list(char *sys, struct tracepoint_path *tps)
 	return false;
 }
 
+#define for_each_event(dir, dent, tps)				\
+	while ((dent = readdir(dir)))				\
+		if (dent->d_type == DT_DIR &&			\
+		    (strcmp(dent->d_name, ".")) &&		\
+		    (strcmp(dent->d_name, "..")))		\
+
 static int copy_event_system(const char *sys, struct tracepoint_path *tps)
 {
 	struct dirent *dent;
@@ -186,12 +192,10 @@ static int copy_event_system(const char *sys, struct tracepoint_path *tps)
 		return -errno;
 	}
 
-	while ((dent = readdir(dir))) {
-		if (dent->d_type != DT_DIR ||
-		    strcmp(dent->d_name, ".") == 0 ||
-		    strcmp(dent->d_name, "..") == 0 ||
-		    !name_in_tp_list(dent->d_name, tps))
+	for_each_event(dir, dent, tps) {
+		if (!name_in_tp_list(dent->d_name, tps))
 			continue;
+
 		if (asprintf(&format, "%s/%s/format", sys, dent->d_name) < 0) {
 			err = -ENOMEM;
 			goto out;
@@ -210,12 +214,10 @@ static int copy_event_system(const char *sys, struct tracepoint_path *tps)
 	}
 
 	rewinddir(dir);
-	while ((dent = readdir(dir))) {
-		if (dent->d_type != DT_DIR ||
-		    strcmp(dent->d_name, ".") == 0 ||
-		    strcmp(dent->d_name, "..") == 0 ||
-		    !name_in_tp_list(dent->d_name, tps))
+	for_each_event(dir, dent, tps) {
+		if (!name_in_tp_list(dent->d_name, tps))
 			continue;
+
 		if (asprintf(&format, "%s/%s/format", sys, dent->d_name) < 0) {
 			err = -ENOMEM;
 			goto out;
@@ -290,13 +292,11 @@ static int record_event_files(struct tracepoint_path *tps)
 		goto out;
 	}
 
-	while ((dent = readdir(dir))) {
-		if (dent->d_type != DT_DIR ||
-		    strcmp(dent->d_name, ".") == 0 ||
-		    strcmp(dent->d_name, "..") == 0 ||
-		    strcmp(dent->d_name, "ftrace") == 0 ||
+	for_each_event(dir, dent, tps) {
+		if (strcmp(dent->d_name, "ftrace") == 0 ||
 		    !system_in_tp_list(dent->d_name, tps))
 			continue;
+
 		count++;
 	}
 
@@ -307,13 +307,11 @@ static int record_event_files(struct tracepoint_path *tps)
 	}
 
 	rewinddir(dir);
-	while ((dent = readdir(dir))) {
-		if (dent->d_type != DT_DIR ||
-		    strcmp(dent->d_name, ".") == 0 ||
-		    strcmp(dent->d_name, "..") == 0 ||
-		    strcmp(dent->d_name, "ftrace") == 0 ||
+	for_each_event(dir, dent, tps) {
+		if (strcmp(dent->d_name, "ftrace") == 0 ||
 		    !system_in_tp_list(dent->d_name, tps))
 			continue;
+
 		if (asprintf(&sys, "%s/%s", path, dent->d_name) < 0) {
 			err = -ENOMEM;
 			goto out;