[PATCH 05/10] perf util: Parse header_page to get proper long size

[Namhyung Kim <namhyung@kernel.org>]

From: Namhyung Kim <namhyung.kim@lge.com>

The header_page file describes the format of the ring buffer page
which is used by ftrace (not perf).  And size of "commit" field (I
guess it's older name was 'size') represents the real size of long
type used for kernel.  So update the pevent's long size.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/perf/util/trace-event-read.c | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/trace-event-read.c b/tools/perf/util/trace-event-read.c
index fa45fca2a2d3..b4e8bdd13671 100644
--- a/tools/perf/util/trace-event-read.c
+++ b/tools/perf/util/trace-event-read.c
@@ -212,6 +212,7 @@ static int read_ftrace_printk(struct pevent *pevent)
 static int read_header_files(struct pevent *pevent)
 {
 	unsigned long long size;
+	char *header_page;
 	char buf[BUFSIZ];
 	int ret = 0;
 
@@ -224,7 +225,23 @@ static int read_header_files(struct pevent *pevent)
 	}
 
 	size = read8(pevent);
-	skip(size);
+
+	if (do_read(buf, size) < 0)
+		return -1;
+
+	header_page = malloc(size);
+	if (header_page == NULL)
+		return -1;
+
+	if (!pevent_parse_header_page(pevent, header_page, size,
+				      pevent_get_long_size(pevent))) {
+		/*
+		 * The commit field in the page is of type long,
+		 * use that instead, since it represents the kernel.
+		 */
+		pevent_set_long_size(pevent, pevent->header_page_size_size);
+	}
+	free(header_page);
 
 	if (do_read(buf, 13) < 0)
 		return -1;
-- 
1.7.11.7