path: root/tools/perf/util/session.c

#define _FILE_OFFSET_BITS 64

#include <linux/kernel.h>

#include <byteswap.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/mman.h>

#include "evlist.h"
#include "evsel.h"
#include "session.h"
#include "sort.h"
#include "util.h"

static int perf_session__read_evlist(struct perf_session *session)
{
	int i, j;

	session->evlist = perf_evlist__new(NULL, NULL);
	if (session->evlist == NULL)
		return -ENOMEM;

	for (i = 0; i < session->header.attrs; ++i) {
		struct perf_header_attr *hattr = session->header.attr[i];
		struct perf_evsel *evsel = perf_evsel__new(&hattr->attr, i);

		if (evsel == NULL)
			goto out_delete_evlist;
		/*
		 * Do it before so that if perf_evsel__alloc_id fails, this
		 * entry gets purged too at perf_evlist__delete().
		 */
		perf_evlist__add(session->evlist, evsel);
		/*
		 * We don't have the cpu and thread maps on the header, so
		 * for allocating the perf_sample_id table we fake 1 cpu and
		 * hattr->ids threads.
		 */
		if (perf_evsel__alloc_id(evsel, 1, hattr->ids))
			goto out_delete_evlist;

		for (j = 0; j < hattr->ids; ++j)
			perf_evlist__id_hash(session->evlist, evsel, 0, j,
					     hattr->id[j]);
	}

	return 0;

out_delete_evlist:
	perf_evlist__delete(session->evlist);
	session->evlist = NULL;
	return -ENOMEM;
}

static int perf_session__open(struct perf_session *self, bool force)
{
	struct stat input_stat;

	if (!strcmp(self->filename, "-")) {
		self->fd_pipe = true;
		self->fd = STDIN_FILENO;

		if (perf_header__read(self, self->fd) < 0)
			pr_err("incompatible file format");

		return 0;
	}

	self->fd = open(self->filename, O_RDONLY);
	if (self->fd < 0) {
		int err = errno;

		pr_err("failed to open %s: %s", self->filename, strerror(err));
		if (err == ENOENT && !strcmp(self->filename, "perf.data"))
			pr_err("  (try 'perf record' first)");
		pr_err("\n");
		return -errno;
	}

	if (fstat(self->fd, &input_stat) < 0)
		goto out_close;

	if (!force && input_stat.st_uid && (input_stat.st_uid != geteuid())) {
		pr_err("file %s not owned by current user or root\n",
		       self->filename);
		goto out_close;
	}

	if (!input_stat.st_size) {
		pr_info("zero-sized file (%s), nothing to do!\n",
			self->filename);
		goto out_close;
	}

	if (perf_header__read(self,