/*
 * sysfs_dir.c
 *
 * Directory utility functions for libsysfs
 *
 * Copyright (C) IBM Corp. 2003-2005
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *
 *  This library 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
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 *
 */
#include "libsysfs.h"
#include "sysfs.h"

/**
 * sysfs_close_attribute: closes and cleans up attribute
 * @sysattr: attribute to close.
 */
void sysfs_close_attribute(struct sysfs_attribute *sysattr)
{
	if (sysattr) {
		if (sysattr->value)
			free(sysattr->value);
		free(sysattr);
	}
}

/**
 * alloc_attribute: allocates and initializes attribute structure
 * returns struct sysfs_attribute with success and NULL with error.
 */
static struct sysfs_attribute *alloc_attribute(void)
{
	return (struct sysfs_attribute *)
			calloc(1, sizeof(struct sysfs_attribute));
}

/**
 * sysfs_open_attribute: creates sysfs_attribute structure
 * @path: path to attribute.
 * returns sysfs_attribute struct with success and NULL with error.
 */
struct sysfs_attribute *sysfs_open_attribute(const char *path)
{
	struct sysfs_attribute *sysattr = NULL;
	struct stat fileinfo;

	if (!path) {
		errno = EINVAL;
		return NULL;
	}
	sysattr = alloc_attribute();
	if (!sysattr) {
		dprintf("Error allocating attribute at %s\n", path);
		return NULL;
	}
	if (sysfs_get_name_from_path(path, sysattr->name,
				SYSFS_NAME_LEN) != 0) {
		dprintf("Error retrieving attrib name from path: %s\n", path);
		sysfs_close_attribute(sysattr);
		return NULL;
	}
	safestrcpy(sysattr->path, path);
	if ((stat(sysattr->path, &fileinfo)) != 0) {
		dprintf("Stat failed: No such attribute?\n");
		sysattr->method = 0;
		free(sysattr);
		sysattr = NULL;
	} else {
		if (fileinfo.st_mode & S_IRUSR)
			sysattr->method |= SYSFS_METHOD_SHOW;
		if (fileinfo.st_mode & S_IWUSR)
			sysattr->method |= SYSFS_METHOD_STORE;
	}

	return sysattr;
}

/**
 * sysfs_read_attribute: reads value from attribute
 * @sysattr: attribute to read
 * returns 0 with success and -1 with error.
 */
int sysfs_read_attribute(struct sysfs_attribute *sysattr)
{
	char *fbuf = NULL;
	char *vbuf = NULL;