/* device.c - device manager */
/*
 *  GRUB  --  GRand Unified Bootloader
 *  Copyright (C) 2002,2005,2007,2008,2009  Free Software Foundation, Inc.
 *
 *  GRUB 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 3 of the License, or
 *(at your option) any later version.
 *
 *  GRUB 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 GRUB.  If not, see <https://www.gnu.org/licenses/>.
 */

#include <grub/device.h>
#include <grub/disk.h>
#include <grub/net.h>
#include <grub/fs.h>
#include <grub/mm.h>
#include <grub/misc.h>
#include <grub/env.h>
#include <grub/partition.h>

GRUB_EXPORT(grub_device_open);
GRUB_EXPORT(grub_device_close);
GRUB_EXPORT(grub_device_iterate);

grub_device_t
grub_device_open(const char *name) {
	grub_disk_t disk = 0;
	grub_device_t dev = 0;

	if (!name) {
		name = grub_env_get ("root");
		if (*name == '\0') {
			grub_error (GRUB_ERR_BAD_DEVICE, "no device is set");
			goto fail;
		}
	}

	dev = grub_malloc (sizeof (*dev));
	if (!dev) {
		goto fail;
	}

	/* Try to open a disk.  */
	disk = grub_disk_open (name);
	if (!disk) {
		goto fail;
	}

	dev->disk = disk;
	dev->net = 0; /* FIXME */

	return dev;

fail:
	if (disk) {
		grub_disk_close (disk);
	}

	grub_free (dev);

	return 0;
}

grub_err_t
grub_device_close(grub_device_t device) {
	if (device->disk) {
		grub_disk_close (device->disk);
	}

	grub_free (device);

	return grub_errno;
}

struct grub_device_iterate_closure {
	int (*hook) (const char *name, void *closure);
	void *closure;
	struct part_ent {
		struct part_ent *next;
		char *name;
	} *ents;
};

static int
iterate_partition(grub_disk_t disk, const grub_partition_t partition, void *closure) {
	struct grub_device_iterate_closure *c = closure;
	char *partition_name;
	struct part_ent *p;

	partition_name = grub_partition_get_name (partition);
	if (!partition_name) {
		return 1;
	}

	p = grub_malloc (sizeof (*p));
	if (!p) {
		grub_free (partition_name);
		return 1;
	}

	p->name = grub_xasprintf ("%s,%s", disk->name, partition_name);
	if (!p->name) {
		grub_free (partition_name);
		grub_free (p);
		return 1;
	}
	grub_free (partition_name);

	p->next = c->ents;
	c->ents = p;

	return 0;
}

static int
iterate_disk(const char *disk_name, void *closure) {
	struct grub_device_iterate_closure *c = closure;
	grub_device_t dev;

	if (c->hook (disk_name, c->closure)) {
		return 1;
	}

	dev = grub_device_open (disk_name);
	if (!dev) {
		grub_errno = GRUB_ERR_NONE;
		return 0;
	}

	if (dev->disk && dev->disk->has_partitions) {
		struct part_ent *p;
		int ret = 0;

		c->ents = NULL;
		(void)grub_partition_iterate (dev->disk, iterate_partition, c);
		grub_device_close (dev);

		grub_errno = GRUB_ERR_NONE;

		p = c->ents;
		while (p != NULL) {
			struct part_ent *next = p->next;

			if (!ret) {
				ret = c->hook (p->name, c->closure);
			}
			grub_free (p->name);
			grub_free (p);
			p = next;
		}

		return ret;
	}

	grub_device_close (dev);
	return 0;
}

int grub_device_iterate(int(*hook)(const char *name, void *closure),
	void *closure) {
	struct grub_device_iterate_closure c;

	c.hook = hook;
	c.closure = closure;
	/* Only disk devices are supported at the moment.  */
	return grub_disk_dev_iterate (iterate_disk, &c);
}