finit/src/util.c

/* Misc. shared utility functions for initctl, reboot and finit
 *
 * Copyright (c) 2016  Joachim Nilsson <troglobit@gmail.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include "config.h"
#include <ctype.h>		/* isprint() */
#include <errno.h>
#include <regex.h>
#include <string.h>
#include <stdarg.h>
#include <stdlib.h>
#include <time.h>
#include <unistd.h>
#include <sys/sysinfo.h>	/* sysinfo() */
#include <lite/lite.h>		/* strlcat() */
#include "util.h"

int   screen_rows  = 24;
int   screen_cols  = 80;
char *prognm       = NULL;

char *progname(char *arg0)
{
       prognm = strrchr(arg0, '/');
       if (prognm)
	       prognm++;
       else
	       prognm = arg0;

       return prognm;
}

int echo(char *file, int append, char *fmt, ...)
{
	va_list ap;
	FILE *fp;

	if (!file)
		fp = stdout;
	else
		fp = fopen(file, append ? "a" : "w");
	if (!fp)
		return -1;

	if (fmt) {
		va_start(ap, fmt);
		vfprintf(fp, fmt, ap);
		va_end(ap);
	}

	/* echo(1) always adds a newline */
	fprintf(fp, "\n");
	if (file)
		fclose(fp);

	return 0;
}

int strtobytes(char *arg)
{
	int mod = 0, bytes;
	size_t pos;

	if (!arg)
		return -1;

	pos = strspn(arg, "0123456789");
	if (arg[pos] != 0) {
		if (arg[pos] == 'G')
			mod = 3;
		else if (arg[pos] == 'M')
			mod = 2;
		else if (arg[pos] == 'k')
			mod = 1;
		else
			return -1;

		arg[pos] = 0;
	}

	bytes = atoi(arg);
	while (mod--)
		bytes *= 1000;

	return bytes;
}

void do_sleep(unsigned int sec)
{
	struct timespec requested_sleep = {
		.tv_sec = sec,
		.tv_nsec = 0,
	};
	while (nanosleep(&requested_sleep, &requested_sleep))
		;
}

/* Seconds since boot, from sysinfo() */
long jiffies(void)
{
	struct sysinfo si;

	if (!sysinfo(&si))
		return si.uptime;

	return 0;
}

char *uptime(long secs, char *buf, size_t len)
{
	long mins, hours, days, years;
	char y[20] = "", d[20] = "", h[20] = "", m[20] = "", s[20] = "";

	if (!buf) {
		errno = EINVAL;
		return NULL;
	}

	years = secs / 31556926;
	secs  = secs % 31556926;
	days  = secs / 86400;
	secs  = secs % 86400;
	hours = secs / 3600;
	secs  = secs % 3600;
	mins  = secs / 60;
	secs  = secs % 60;

	if (years)
		snprintf(y, sizeof(y), "%ld year", years);
	if (days)
		snprintf(d, sizeof(d), "%ld day", days);
	if (hours)
		snprintf(h, sizeof(h), "%ld hour", hours);
	if (mins)
		snprintf(m, sizeof(m), "%ld min", mins);
	if (secs)
		snprintf(s, sizeof(s), "%ld sec", secs);

	snprintf(buf, len, "%s%s%s%s%s%s%s%s%s",
		 y, years ? " " : "",
		 d, days  ? " " : "",
		 h, hours ? " " : "",
		 m, mins  ? " " : "",
		 s);

	return buf;
}

/*
 * Verify string argument is NUL terminated
 * Verify string is a JOB[:ID], JOB and ID
 * can both be string or number, or combo.
 */
char *sanitize(char *arg, size_t len)
{
	const char *regex = "[a-z0-9_]+[:]?[a-z0-9_]*";
	regex_t preg;
	int rc;

	if (strlen(arg) > len)
		return NULL;

	if (regcomp(&preg, regex, REG_ICASE | REG_EXTENDED))
		return NULL;

	rc = regexec(&preg, arg, 0, NULL, 0);
	regfree(&preg);
	if (rc)
		return NULL;

	return arg;
}

/*
 * Called at boot, and shutdown, to (re)initialize the
 * screen size for print() et al.
 */
void screen_init(void)
{
	if (!isatty(STDOUT_FILENO))
		return;

	initscr(&screen_rows, &screen_cols);
}

/*
 * Called when debug mode is enabled to revert back
 * to old-school safe defaults.
 */
void screen_exit(void)
{
	screen_rows = 24;
	screen_cols = 80;
}

/**
 * Local Variables:
 *  indent-tabs-mode: t
 *  c-file-style: "linux"
 * End:
 */