quickstart guide review

[lttng-tools.git] / ltt-sessiond / utils.c

/*
 * Copyright (C)  2011 - David Goulet <david.goulet@polymtl.ca>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * 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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

#define _GNU_SOURCE
#include <errno.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>

#include "utils.h"

/*
 *  get_home_dir
 *
 *  Return pointer to home directory path using the env variable HOME.
 *  No home, NULL is returned.
 */
const char *get_home_dir(void)
{
	return ((const char *) getenv("HOME"));
}

/*
 *  mkdir_recursive
 *
 *  Create recursively directory using the FULL path.
 */
int mkdir_recursive(const char *path, mode_t mode)
{
    int ret;
    char *p, tmp[PATH_MAX];
    size_t len;
    mode_t old_umask;

    ret = snprintf(tmp, sizeof(tmp), "%s", path);
	if (ret < 0) {
		perror("snprintf mkdir");
		goto error;
	}

    len = ret;
    if (tmp[len - 1] == '/') {
        tmp[len - 1] = 0;
    }

    old_umask = umask(0);
    for (p = tmp + 1; *p; p++) {
        if (*p == '/') {
            *p = 0;
            ret = mkdir(tmp, mode);
            if (ret < 0) {
                if (!(errno == EEXIST)) {
					perror("mkdir recursive");
					ret = errno;
                    goto umask_error;
                }
            }
            *p = '/';
        }
    }

    ret = mkdir(tmp, mode);
	if (ret < 0) {
		ret = errno;
	}

umask_error:
	umask(old_umask);
error:
    return ret;
}