1
2#include <stdio.h>
3#include <unistd.h>
4#include <stdlib.h>
5#include <errno.h>
6#include <sys/types.h>
7#include <sys/stat.h>
8#include <fcntl.h>
9#include <linux/kernel.h>
10#include <traceevent/event-parse.h>
11#include "trace-event.h"
12#include "util.h"
13
14/*
15 * global trace_event object used by trace_event__tp_format
16 *
17 * TODO There's no cleanup call for this. Add some sort of
18 * __exit function support and call trace_event__cleanup
19 * there.
20 */
21static struct trace_event tevent;
22
23int trace_event__init(struct trace_event *t)
24{
25	struct pevent *pevent = pevent_alloc();
26
27	if (pevent) {
28		t->plugin_list = traceevent_load_plugins(pevent);
29		t->pevent  = pevent;
30	}
31
32	return pevent ? 0 : -1;
33}
34
35void trace_event__cleanup(struct trace_event *t)
36{
37	traceevent_unload_plugins(t->plugin_list, t->pevent);
38	pevent_free(t->pevent);
39}
40
41static struct event_format*
42tp_format(const char *sys, const char *name)
43{
44	struct pevent *pevent = tevent.pevent;
45	struct event_format *event = NULL;
46	char path[PATH_MAX];
47	size_t size;
48	char *data;
49
50	scnprintf(path, PATH_MAX, "%s/%s/%s/format",
51		  tracing_events_path, sys, name);
52
53	if (filename__read_str(path, &data, &size))
54		return NULL;
55
56	pevent_parse_format(pevent, &event, data, size, sys);
57
58	free(data);
59	return event;
60}
61
62struct event_format*
63trace_event__tp_format(const char *sys, const char *name)
64{
65	static bool initialized;
66
67	if (!initialized) {
68		int be = traceevent_host_bigendian();
69		struct pevent *pevent;
70
71		if (trace_event__init(&tevent))
72			return NULL;
73
74		pevent = tevent.pevent;
75		pevent_set_flag(pevent, PEVENT_NSEC_OUTPUT);
76		pevent_set_file_bigendian(pevent, be);
77		pevent_set_host_bigendian(pevent, be);
78		initialized = true;
79	}
80
81	return tp_format(sys, name);
82}
83