/*
 *  snapfs/options.c
 */
#define DEBUG_SUBSYSTEM S_SM

#include <linux/module.h>
#include <linux/kmod.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/slab.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/lustre_idl.h>
#include "smfs_internal.h" 


static struct list_head option_list;
char  *options = NULL;
char  *opt_left = NULL;

int init_option(char *data)
{
	INIT_LIST_HEAD(&option_list);
	SM_ALLOC(options, strlen(data) + 1);
	if (!options) {
		CERROR("Can not allocate memory \n");
		return -ENOMEM;
	}
	memcpy(options, data, strlen(data));
	opt_left = options;
	return 0;
}
/*cleanup options*/
void cleanup_option(void)
{
	struct option *option;
	while (!list_empty(&option_list)) {
		option = list_entry(option_list.next, struct option, list);
		list_del(&option->list);
		SM_FREE(option->opt, strlen(option->opt) + 1);
		if (option->value)
			SM_FREE(option->value, strlen(option->value) + 1);
		SM_FREE(option, sizeof(struct option));
	}
	SM_FREE(options, strlen(options) + 1);
}
int get_opt(struct option **option, char **pos)
{
	char  *name, *value, *left, *tmp;
	struct option *tmp_opt;
	int  length = 0;

	*pos = opt_left;

	if (! *opt_left)
		return -ENODATA;
	left = strchr(opt_left, ',');
	if (left == opt_left) 
		return -EINVAL;
	if (!left){
		left = opt_left + strlen(opt_left);	
	}	

	SM_ALLOC(tmp_opt, sizeof(struct option));   	
	tmp_opt->opt = NULL;
	tmp_opt->value = NULL;

	tmp = opt_left;
	while(tmp != left && *tmp != '=') {
		length++;
		tmp++;
	}	
	SM_ALLOC(name, length + 1);
	tmp_opt->opt = name;
	memset(name, 0, length + 1);
	while (opt_left != tmp) *name++ = *opt_left++;

	if (*tmp == '=') {
		/*this option has value*/
		opt_left ++; /*after '='*/
		if (left == opt_left) {
			SM_FREE(tmp_opt->opt, length);
			SM_FREE(tmp_opt, sizeof(struct option));
			opt_left = *pos;
			return -EINVAL;
		}
		length = left - opt_left + 1;
		SM_ALLOC(value, length);
		tmp_opt->value = value;
		memset(value, 0, length);
		while (opt_left != left) *value++ = *opt_left++;
	}
	list_add(&tmp_opt->list, &option_list);
	if (*opt_left == ',') opt_left ++; /*after ','*/	
	*option = tmp_opt;
	return 0;
}