119 lines · c
1// SPDX-License-Identifier: GPL-2.02#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 <linux/err.h>11#include <traceevent/event-parse.h>12#include <api/fs/tracing_path.h>13#include <api/fs/fs.h>14#include "trace-event.h"15#include "machine.h"16 17/*18 * global trace_event object used by trace_event__tp_format19 *20 * TODO There's no cleanup call for this. Add some sort of21 * __exit function support and call trace_event__cleanup22 * there.23 */24static struct trace_event tevent;25static bool tevent_initialized;26 27int trace_event__init(struct trace_event *t)28{29 struct tep_handle *pevent = tep_alloc();30 31 if (pevent) {32 t->plugin_list = tep_load_plugins(pevent);33 t->pevent = pevent;34 }35 36 return pevent ? 0 : -1;37}38 39static int trace_event__init2(void)40{41 int be = tep_is_bigendian();42 struct tep_handle *pevent;43 44 if (trace_event__init(&tevent))45 return -1;46 47 pevent = tevent.pevent;48 tep_set_flag(pevent, TEP_NSEC_OUTPUT);49 tep_set_file_bigendian(pevent, be);50 tep_set_local_bigendian(pevent, be);51 tevent_initialized = true;52 return 0;53}54 55int trace_event__register_resolver(struct machine *machine,56 tep_func_resolver_t *func)57{58 if (!tevent_initialized && trace_event__init2())59 return -1;60 61 return tep_set_function_resolver(tevent.pevent, func, machine);62}63 64void trace_event__cleanup(struct trace_event *t)65{66 tep_unload_plugins(t->plugin_list, t->pevent);67 tep_free(t->pevent);68}69 70/*71 * Returns pointer with encoded error via <linux/err.h> interface.72 */73static struct tep_event*74tp_format(const char *sys, const char *name)75{76 char *tp_dir = get_events_file(sys);77 struct tep_handle *pevent = tevent.pevent;78 struct tep_event *event = NULL;79 char path[PATH_MAX];80 size_t size;81 char *data;82 int err;83 84 if (!tp_dir)85 return ERR_PTR(-errno);86 87 scnprintf(path, PATH_MAX, "%s/%s/format", tp_dir, name);88 put_events_file(tp_dir);89 90 err = filename__read_str(path, &data, &size);91 if (err)92 return ERR_PTR(err);93 94 tep_parse_format(pevent, &event, data, size, sys);95 96 free(data);97 return event;98}99 100/*101 * Returns pointer with encoded error via <linux/err.h> interface.102 */103struct tep_event*104trace_event__tp_format(const char *sys, const char *name)105{106 if (!tevent_initialized && trace_event__init2())107 return ERR_PTR(-ENOMEM);108 109 return tp_format(sys, name);110}111 112struct tep_event *trace_event__tp_format_id(int id)113{114 if (!tevent_initialized && trace_event__init2())115 return ERR_PTR(-ENOMEM);116 117 return tep_find_event(tevent.pevent, id);118}119