/*
 *  Gather statistics from performance sensitive code.
 *
 *  Copyright (C) 2013-2020 Cisco Systems, Inc. and/or its affiliates. All rights reserved.
 *  Copyright (C) 2008-2013 Sourcefire, Inc.
 *
 *  Authors: Török Edvin
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as
 *  published by the Free Software Foundation.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 *  MA 02110-1301, USA.
 */
#ifdef HAVE_CONFIG_H
#include "clamav-config.h"
#endif

#include "perflogging.h"
#include <stdio.h>
#ifdef CLI_PERF_LOGGING

__thread last_flushed        = 0;
__thread cli_perf_registered = 0;
__thread uint64_t cli_perf_sum_tls[__LAST_SUMABLE];
__thread uint64_t cli_perf_count_tls[__LAST_COUNTABLE][256];

uint64_t cli_perf_sum[__LAST_SUMABLE];
uint64_t cli_perf_count[__LAST_COUNTABLE][256];

static pthread_key_t thread_exit_key;
int pthread_key_create(pthread_key_t *key, void (*destr_function)(void *));

static void cli_perf_thread_exit(void *arg)
{
    /* save counters into global */
    cli_perf_flush();
}

void __attribute__((constructor)) __cli_perf_init(void)
{
    pthread_key_create(&thread_exit_key, cli_perf_thread_exit);
}

void __attribute__((destructor)) __cli_perf_exit(void)
{
    cli_perf_thread_exit(NULL);
}

static int dummy;
void cli_perf_register(void)
{
    /* set a fake key, so that destructor gets called */
    pthread_setspecific(thread_exit_key, &dummy);
    cli_perf_registered = 1;
}

static const char *perf_log_names_sum[__LAST_SUMABLE] = {
    "raw scanned",
    "filter scanned",
    "AC scanned",
    "BM scanned"};

static const char *perf_log_names_cnt[__LAST_COUNTABLE] = {
    "trie bytes scanned",
    "filter position load",
    "filter end load",
    "trie pattern original length"};

#define NONE __LAST_SUMABLE
static enum perf_log_sumable perf_log_percent[__LAST_SUMABLE] = {
    NONE,
    RAW_BYTES_SCANNED,
    RAW_BYTES_SCANNED,
    RAW_BYTES_SCANNED,
};

static enum perf_log_countable perf_log_percent_cnt[__LAST_COUNTABLE] = {
    RAW_BYTES_SCANNED,
    NONE,
    NONE,
    NONE,
};

static void cli_perf_print(void)
{
    enum perf_log_sumable i;
    enum perf_log_countable j;
    unsigned k;

    uint64_t raw_scanned = cli_perf_sum[RAW_BYTES_SCANNED];
    const double MEGA    = 1024 * 1024.0;

    /* in multiscan mode multiple threads can output, so output a unique id
	 * here*/
    printf("PERF: %p\n", &cli_perf_registered);
    for (i = 0; i < __LAST_SUMABLE; i++) {
        printf("PERF: %s: %g MB", perf_log_names_sum[i], cli_perf_sum[i] / MEGA);
        if (perf_log_percent[i] != NONE)
            printf("(%6.3f%%)", 100.0 * cli_perf_sum[i] / cli_perf_sum[perf_log_percent[i]]);
        printf("\n");
    }
    printf("\n");
    for (j = 0; j < __LAST_COUNTABLE; j++) {
        printf("PERF: %s: ", perf_log_names_cnt[j]);
        for (k = 0; k < 256; k++)
            if (cli_perf_count[j][k]) {
                printf(" %u -> %ju", k, cli_perf_count[j][k]);
                if (perf_log_percent_cnt[j] != NONE)
                    printf("(%6.3f%%)", 100.0 * cli_perf_count[j][k] / cli_perf_sum[perf_log_percent_cnt[j]]);
            }
        printf("\n");
    }
    printf("\n");
}

static pthread_mutex_t cli_perf_log_mutex = PTHREAD_MUTEX_INITIALIZER;
void cli_perf_flush(void)
{
    unsigned i, j;

    pthread_mutex_lock(&cli_perf_log_mutex);

    for (i = 0; i < __LAST_SUMABLE; i++) {
        cli_perf_sum[i] += cli_perf_sum_tls[i];
        cli_perf_sum_tls[i] = 0;
    }

    for (i = 0; i < __LAST_COUNTABLE; i++) {
        for (j = 0; j < 256; j++) {
            cli_perf_count[i][j] += cli_perf_count_tls[i][j];
            cli_perf_count_tls[i][j] = 0;
        }
    }

    cli_perf_print();
    pthread_mutex_unlock(&cli_perf_log_mutex);
}
#endif
