/*
 * Copyright (c) 2011 Martin Sucha
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup test
 * @{
 */

/**
 * @file	bnchmark.c
 * This program measures time for various actions and writes the results
 * to a file.
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <mem.h>
#include <loc.h>
#include <byteorder.h>
#include <sys/types.h>
#include <sys/typefmt.h>
#include <inttypes.h>
#include <errno.h>
#include <time.h>
#include <dirent.h>

#define NAME	"bnchmark"
#define BUFSIZE 8096
#define MBYTE (1024*1024)

typedef int(*measure_func_t)(void *);
typedef unsigned long umseconds_t; /* milliseconds */

static void syntax_print(void);

static int measure(measure_func_t fn, void* data, umseconds_t *result)
{
	struct timeval start_time;
	int rc;
	rc = gettimeofday(&start_time, NULL);
	if (rc != EOK) {
		fprintf(stderr, "gettimeofday failed\n");
		return rc;
	}
	
	rc = fn(data);
	if (rc != EOK) {
		fprintf(stderr, "measured function failed\n");
		return rc;
	}

	struct timeval final_time;
	rc = gettimeofday(&final_time, NULL);
	if (rc != EOK) {
		fprintf(stderr, "gettimeofday failed\n");
		return rc;
	}
	
	/* Calculate time difference in milliseconds */
	*result = ((final_time.tv_usec - start_time.tv_usec) / 1000) +
	    ((final_time.tv_sec - start_time.tv_sec) * 1000);
	return EOK;
}

static int sequential_read_file(void *data)
{
	char *path = (char *) data;
	char *buf = malloc(BUFSIZE);

	if (buf == NULL) {
		return ENOMEM;
	}
	
	FILE *file = fopen(path, "r");
	if (file == NULL) {
		fprintf(stderr, "Failed opening file: %s\n", path);
		free(buf);
		return EIO;
	}
	
	while (!feof(file)) {
		fread(buf, 1, BUFSIZE, file);
		if (ferror(file)) {
			fprintf(stderr, "Failed reading file\n");
			fclose(file);
			free(buf);
			return EIO;
		}
	}
	
	fclose(file);
	free(buf);
	return EOK;
}

static int sequential_read_dir(void *data)
{
	char *path = (char *) data;
	
	DIR *dir = opendir(path);
	if (dir == NULL) {
		fprintf(stderr, "Failed opening directory: %s\n", path);
		return EIO;
	}

	struct dirent *dp;
	
	while ((dp = readdir(dir))) {
		/* Do nothing */
	}
	
	closedir(dir);
	return EOK;
}

int main(int argc, char **argv)
{
	int rc;
	umseconds_t milliseconds_taken;
	char *path = NULL;
	measure_func_t fn = NULL;
	int iteration;
	int iterations;
	char *log_str = NULL;
	char *test_type = NULL;
	char *endptr;
	
	if (argc < 5) {
		fprintf(stderr, NAME ": Error, argument missing.\n");
		syntax_print();
		return 1;
	}
	
	if (argc > 5) {
		fprintf(stderr, NAME ": Error, too many arguments.\n");
		syntax_print();
		return 1;
	}
	
	// Skip program name
	--argc; ++argv;

	iterations = strtol(*argv, &endptr, 10);
	if (*endptr != '\0') {
		printf(NAME ": Error, invalid argument (iterations).\n");
		syntax_print();
		return 1;
	}
	
	--argc; ++argv;
	test_type = *argv;

	--argc; ++argv;
	log_str = *argv;

	--argc; ++argv;
	path = *argv;
	
	if (str_cmp(test_type, "sequential-file-read") == 0) {
		fn = sequential_read_file;
	}
	else if (str_cmp(test_type, "sequential-dir-read") == 0) {
		fn = sequential_read_dir;
	}
	else {
		fprintf(stderr, "Error, unknown test type\n");
		syntax_print();
		return 1;
	}

	for (iteration = 0; iteration < iterations; iteration++) {
		rc = measure(fn, path, &milliseconds_taken);
		if (rc != EOK) {
			fprintf(stderr, "Error %d\n", rc);
			return 1;
		}
	
		printf("%s;%s;%s;%lu;ms\n", test_type, path, log_str, milliseconds_taken);
	}

	return 0;
}


static void syntax_print(void)
{
	fprintf(stderr, "syntax: " NAME " <iterations> <test type> <log-str> <path>\n");
	fprintf(stderr, "  <iterations>    number of times to run a given test\n");
	fprintf(stderr, "  <test-type>     one of:\n");
	fprintf(stderr, "                    sequential-file-read\n");
	fprintf(stderr, "                    sequential-dir-read\n");
	fprintf(stderr, "  <log-str>       a string to attach to results\n");
	fprintf(stderr, "  <path>          file/directory to use for testing\n");
}

/**
 * @}
 */