/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or https://opensource.org/licenses/CDDL-1.0.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright (c) 2017, Intle Corporation. All rights reserved.
 */

#include <errno.h>
#include <getopt.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <dirent.h>
#include <stddef.h>
#include <libintl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/list.h>
#include <sys/zfs_project.h>

#include "zfs_util.h"
#include "zfs_projectutil.h"

typedef struct zfs_project_item {
	list_node_t	zpi_list;
	char		zpi_name[0];
} zfs_project_item_t;

static void
zfs_project_item_alloc(list_t *head, const char *name)
{
	zfs_project_item_t *zpi;

	zpi = safe_malloc(sizeof (zfs_project_item_t) + strlen(name) + 1);
	strcpy(zpi->zpi_name, name);
	list_insert_tail(head, zpi);
}

static int
zfs_project_sanity_check(const char *name, zfs_project_control_t *zpc,
    struct stat *st)
{
	int ret;

	ret = stat(name, st);
	if (ret) {
		(void) fprintf(stderr, gettext("failed to stat %s: %s\n"),
		    name, strerror(errno));
		return (ret);
	}

	if (!S_ISREG(st->st_mode) && !S_ISDIR(st->st_mode)) {
		(void) fprintf(stderr, gettext("only support project quota on "
		    "regular file or directory\n"));
		return (-1);
	}

	if (!S_ISDIR(st->st_mode)) {
		if (zpc->zpc_dironly) {
			(void) fprintf(stderr, gettext(
			    "'-d' option on non-dir target %s\n"), name);
			return (-1);
		}

		if (zpc->zpc_recursive) {
			(void) fprintf(stderr, gettext(
			    "'-r' option on non-dir target %s\n"), name);
			return (-1);
		}
	}

	return (0);
}

static int
zfs_project_load_projid(const char *name, zfs_project_control_t *zpc)
{
	zfsxattr_t fsx;
	int ret, fd;

	fd = open(name, O_RDONLY | O_NOCTTY);
	if (fd < 0) {
		(void) fprintf(stderr, gettext("failed to open %s: %s\n"),
		    name, strerror(errno));
		return (fd);
	}

	ret = ioctl(fd, ZFS_IOC_FSGETXATTR, &fsx);
	if (ret)
		(void) fprintf(stderr,
		    gettext("failed to get xattr for %s: %s\n"),
		    name, strerror(errno));
	else
		zpc->zpc_expected_projid = fsx.fsx_projid;

	close(fd);
	return (ret);
}

static int
zfs_project_handle_one(const char *name, zfs_project_control_t *zpc)
{
	zfsxattr_t fsx;
	int ret, fd;

	fd = open(name, O_RDONLY | O_NOCTTY);
	if (fd < 0) {
		if (errno == ENOENT && zpc->zpc_ignore_noent)
			return (0);

		(void) fprintf(stderr, gettext("failed to open %s: %s\n"),
		    name, strerror(errno));
		return (fd);
	}

	ret = ioctl(fd, ZFS_IOC_FSGETXATTR, &fsx);
	if (ret) {
		(void) fprintf(stderr,
		    gettext("failed to get xattr for %s: %s\n"),
		    name, strerror(errno));
		goto out;
	}

	switch (zpc->zpc_op) {
	case ZFS_PROJECT_OP_LIST:
		(void) printf("%5u %c %s\n", fsx.fsx_projid,
		    (fsx.fsx_xflags & ZFS_PROJINHERIT_FL) ? 'P' : '-', name);
		goto out;
	case ZFS_PROJECT_OP_CHECK:
		if (fsx.fsx_projid == zpc->zpc_expected_projid &&
		    fsx.fsx_xflags & ZFS_PROJINHERIT_FL)
			goto out;

		if (!zpc->zpc_newline) {
			char c = '\0';

			(void) printf("%s%c", name, c);
			goto out;
		}

		if (fsx.fsx_projid != zpc->zpc_expected_projid)
			(void) printf("%s - project ID is not set properly "
			    "(%u/%u)\n", name, fsx.fsx_projid,
			    (uint32_t)zpc->zpc_expected_projid);

		if (!(fsx.fsx_xflags & ZFS_PROJINHERIT_FL))
			(void) printf("%s - project inherit flag is not set\n",
			    name);

		goto out;
	case ZFS_PROJECT_OP_CLEAR:
		if (!(fsx.fsx_xflags & ZFS_PROJINHERIT_FL) &&
		    (zpc->zpc_keep_projid ||
		    fsx.fsx_projid == ZFS_DEFAULT_PROJID))
			goto out;

		fsx.fsx_xflags &= ~ZFS_PROJINHERIT_FL;
		if (!zpc->zpc_keep_projid)
			fsx.fsx_projid = ZFS_DEFAULT_PROJID;
		break;
	case ZFS_PROJECT_OP_SET:
		if (fsx.fsx_projid == zpc->zpc_expected_projid &&
		    (!zpc->zpc_set_flag || fsx.fsx_xflags & ZFS_PROJINHERIT_FL))
			goto out;

		fsx.fsx_projid = zpc->zpc_expected_projid;
		if (zpc->zpc_set_flag)
			fsx.fsx_xflags |= ZFS_PROJINHERIT_FL;
		break;
	default:
		ASSERT(0);
		break;
	}

	ret = ioctl(fd, ZFS_IOC_FSSETXATTR, &fsx);
	if (ret)
		(void) fprintf(stderr,
		    gettext("failed to set xattr for %s: %s\n"),
		    name, strerror(errno));

out:
	close(fd);
	return (ret);
}

static int
zfs_project_handle_dir(const char *name, zfs_project_control_t *zpc,
    list_t *head)
{
	struct dirent *ent;
	DIR *dir;
	int ret = 0;

	dir = opendir(name);
	if (dir == NULL) {
		if (errno == ENOENT && zpc->zpc_ignore_noent)
			return (0);

		ret = -errno;
		(void) fprintf(stderr, gettext("failed to opendir %s: %s\n"),
		    name, strerror(errno));
		return (ret);
	}

	/* Non-top item, ignore the case of being removed or renamed by race. */
	zpc->zpc_ignore_noent = B_TRUE;
	errno = 0;
	while (!ret && (ent = readdir(dir)) != NULL) {
		char *fullname;

		/* skip "." and ".." */
		if (strcmp(ent->d_name, ".") == 0 ||
		    strcmp(ent->d_name, "..") == 0)
			continue;

		if (strlen(ent->d_name) + strlen(name) + 1 >= PATH_MAX) {
			errno = ENAMETOOLONG;
			break;
		}

		if (asprintf(&fullname, "%s/%s", name, ent->d_name) == -1) {
			errno = ENOMEM;
			break;
		}

		ret = zfs_project_handle_one(fullname, zpc);
		if (!ret && zpc->zpc_recursive && ent->d_type == DT_DIR)
			zfs_project_item_alloc(head, fullname);

		free(fullname);
	}

	if (errno && !ret) {
		ret = -errno;
		(void) fprintf(stderr, gettext("failed to readdir %s: %s\n"),
		    name, strerror(errno));
	}

	closedir(dir);
	return (ret);
}

int
zfs_project_handle(const char *name, zfs_project_control_t *zpc)
{
	zfs_project_item_t *zpi;
	struct stat st;
	list_t head;
	int ret;

	ret = zfs_project_sanity_check(name, zpc, &st);
	if (ret)
		return (ret);

	if ((zpc->zpc_op == ZFS_PROJECT_OP_SET ||
	    zpc->zpc_op == ZFS_PROJECT_OP_CHECK) &&
	    zpc->zpc_expected_projid == ZFS_INVALID_PROJID) {
		ret = zfs_project_load_projid(name, zpc);
		if (ret)
			return (ret);
	}

	zpc->zpc_ignore_noent = B_FALSE;
	ret = zfs_project_handle_one(name, zpc);
	if (ret || !S_ISDIR(st.st_mode) || zpc->zpc_dironly ||
	    (!zpc->zpc_recursive &&
	    zpc->zpc_op != ZFS_PROJECT_OP_LIST &&
	    zpc->zpc_op != ZFS_PROJECT_OP_CHECK))
		return (ret);

	list_create(&head, sizeof (zfs_project_item_t),
	    offsetof(zfs_project_item_t, zpi_list));
	zfs_project_item_alloc(&head, name);
	while ((zpi = list_remove_head(&head)) != NULL) {
		if (!ret)
			ret = zfs_project_handle_dir(zpi->zpi_name, zpc, &head);
		free(zpi);
	}

	return (ret);
}