/**
 * @file opd_sample_files.c
 * Management of sample files
 *
 * @remark Copyright 2002 OProfile authors
 * @remark Read the file COPYING
 *
 * @author John Levon
 * @author Philippe Elie
 */

#include <sys/types.h>
 
#include "opd_sample_files.h"
#include "opd_image.h"
#include "opd_printf.h"
#include "opd_events.h"
#include "oprofiled.h"

#include "op_sample_file.h"
#include "op_file.h"
#include "op_config.h"
#include "op_mangle.h"
#include "op_events.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>

/** All sfiles are on this list. */
static LIST_HEAD(lru_list);

/* this value probably doesn't matter too much */
#define LRU_AMOUNT 1000
static int opd_24_sfile_lru_clear(void)
{
	struct list_head * pos;
	struct list_head * pos2;
	struct opd_24_sfile * sfile;
	int amount = LRU_AMOUNT;

	verbprintf(vsfile, "image lru clear\n");

	if (list_empty(&lru_list))
		return 1;

	list_for_each_safe(pos, pos2, &lru_list) {
		if (!--amount)
			break;
		sfile = list_entry(pos, struct opd_24_sfile, lru_next);
		odb_close(&sfile->sample_file);
		list_del_init(&sfile->lru_next);
	}

	return 0;
}


void opd_24_sfile_lru(struct opd_24_sfile * sfile)
{
	list_del(&sfile->lru_next);
	list_add_tail(&sfile->lru_next, &lru_list);
}


static char * opd_mangle_filename(struct opd_image const * image, int counter,
                                  int cpu_nr)
{
	char * mangled;
	struct mangle_values values;
	struct opd_event * event = find_counter_event(counter);

	values.flags = 0;
	if (image->kernel)
		values.flags |= MANGLE_KERNEL;

	if (separate_thread) {
		values.flags |= MANGLE_TGID | MANGLE_TID;
		values.tid = image->tid;
		values.tgid = image->tgid;
	}

	if (separate_cpu) {
		values.flags |= MANGLE_CPU;
		values.cpu = cpu_nr;
	}

	values.event_name = event->name;
	values.count = event->count;
	values.unit_mask = event->um;

	values.image_name = image->name;
	values.dep_name = separate_lib && image->app_name
		? image->app_name : image->name;

	mangled = op_mangle_filename(&values);

	return mangled;
}


int opd_open_24_sample_file(struct opd_image * image, int counter, int cpu_nr)
{
	char * mangled;
	struct opd_24_sfile * sfile;
	int err;

	mangled = opd_mangle_filename(image, counter, cpu_nr);

	verbprintf(vsfile, "Opening \"%s\"\n", mangled);

	create_path(mangled);

	sfile = image->sfiles[cpu_nr][counter];
	if (!sfile) {
		sfile = malloc(sizeof(struct opd_24_sfile));
		list_init(&sfile->lru_next);
		odb_init(&sfile->sample_file);
		image->sfiles[cpu_nr][counter] = sfile;
	}

	list_del(&sfile->lru_next);
	list_add_tail(&sfile->lru_next, &lru_list);

retry:
	err = odb_open(&sfile->sample_file, mangled, ODB_RDWR,
                       sizeof(struct opd_header));

	/* This can naturally happen when racing against opcontrol --reset. */
	if (err) {
		if (err == EMFILE) {
			if (opd_24_sfile_lru_clear()) {
				printf("LRU cleared but odb_open() fails for %s.\n", mangled);
				abort();
			}
			goto retry;
		}

		fprintf(stderr, "oprofiled: open of %s failed: %s\n",
		        mangled, strerror(err));
		goto out;
	}

	fill_header(odb_get_data(&sfile->sample_file), counter, 0, 0,
		    image->kernel, 0, 0, 0, image->mtime);

out:
	free(mangled);
	return err;
}


void opd_sync_samples_files(void)
{
	struct list_head * pos;
	struct opd_24_sfile * sfile;

	list_for_each(pos, &lru_list) {
		sfile = list_entry(pos, struct opd_24_sfile, lru_next);
		odb_sync(&sfile->sample_file);
	}
}


void opd_close_image_samples_files(struct opd_image * image)
{
	uint i, j;
	for (i = 0 ; i < op_nr_counters ; ++i) {
		for (j = 0; j < NR_CPUS; ++j) {
			if (image->sfiles[j] && image->sfiles[j][i]) {
				odb_close(&image->sfiles[j][i]->sample_file);
				list_del(&image->sfiles[j][i]->lru_next);
				free(image->sfiles[j][i]);
				image->sfiles[j][i] = 0;
			}
		}
	}
}