/* SPDX-License-Identifier: GPL-3.0-or-later */
/*
 * restore_fstree.c
 *
 * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
 */
#include "rdsquashfs.h"

static int create_node(tree_node_t *n, int flags)
{
	tree_node_t *c;
	int fd, ret;
	char *name;

	if (!(flags & UNPACK_QUIET)) {
		name = fstree_get_path(n);
		printf("creating %s\n", name);
		free(name);
	}

	switch (n->mode & S_IFMT) {
	case S_IFDIR:
		if (mkdir(n->name, 0755) && errno != EEXIST) {
			fprintf(stderr, "mkdir %s: %s\n",
				n->name, strerror(errno));
			return -1;
		}

		if (pushd(n->name))
			return -1;

		for (c = n->data.dir->children; c != NULL; c = c->next) {
			if (create_node(c, flags))
				return -1;
		}

		if (popd())
			return -1;
		break;
	case S_IFLNK:
		if (symlink(n->data.slink_target, n->name)) {
			fprintf(stderr, "ln -s %s %s: %s\n",
				n->data.slink_target, n->name,
				strerror(errno));
			return -1;
		}
		break;
	case S_IFSOCK:
	case S_IFIFO:
		if (mknod(n->name, (n->mode & S_IFMT) | 0700, 0)) {
			fprintf(stderr, "creating %s: %s\n",
				n->name, strerror(errno));
			return -1;
		}
		break;
	case S_IFBLK:
	case S_IFCHR:
		if (mknod(n->name, n->mode & S_IFMT, n->data.devno)) {
			fprintf(stderr, "creating device %s: %s\n",
				n->name, strerror(errno));
			return -1;
		}
		break;
	case S_IFREG:
		fd = open(n->name, O_WRONLY | O_CREAT | O_EXCL, 0600);
		if (fd < 0) {
			fprintf(stderr, "creating %s: %s\n",
				n->name, strerror(errno));
			return -1;
		}

		close(fd);

		if (n->parent != NULL) {
			n->data.file->input_file = fstree_get_path(n);
		} else {
			n->data.file->input_file = strdup(n->name);
		}

		if (n->data.file->input_file == NULL) {
			perror("restoring file path");
			return -1;
		}

		ret = canonicalize_name(n->data.file->input_file);
		assert(ret == 0);
		break;
	default:
		break;
	}

	return 0;
}

static int set_attribs(fstree_t *fs, tree_node_t *n, int flags)
{
	tree_node_t *c;

	if (S_ISDIR(n->mode)) {
		if (pushd(n->name))
			return -1;

		for (c = n->data.dir->children; c != NULL; c = c->next) {
			if (set_attribs(fs, c, flags))
				return -1;
		}

		if (popd())
			return -1;
	}

#ifdef HAVE_SYS_XATTR_H
	if ((flags & UNPACK_SET_XATTR) && n->xattr != NULL) {
		size_t i, len, kidx, vidx;
		const char *key, *value;

		for (i = 0; i < n->xattr->num_attr; ++i) {
			kidx = n->xattr->attr[i].key_index;
			vidx = n->xattr->attr[i].value_index;

			key = str_table_get_string(&fs->xattr_keys, kidx);
			value = str_table_get_string(&fs->xattr_values, vidx);
			len = strlen(value);

			if (lsetxattr(n->name, key, value, len, 0)) {
				fprintf(stderr,
					"setting xattr '%s' on %s: %s\n",
					key, n->name, strerror(errno));
				return -1;
			}
		}
	}
#else
	(void)fs;
#endif

	if (flags & UNPACK_SET_TIMES) {
		struct timespec times[2];

		memset(times, 0, sizeof(times));
		times[0].tv_sec = n->mod_time;
		times[1].tv_sec = n->mod_time;

		if (utimensat(AT_FDCWD, n->name, times, AT_SYMLINK_NOFOLLOW)) {
			fprintf(stderr, "setting timestamp on %s: %s\n",
				n->name, strerror(errno));
			return -1;
		}
	}

	if (flags & UNPACK_CHOWN) {
		if (fchownat(AT_FDCWD, n->name, n->uid, n->gid,
			     AT_SYMLINK_NOFOLLOW)) {
			fprintf(stderr, "chown %s: %s\n",
				n->name, strerror(errno));
			return -1;
		}
	}

	if (flags & UNPACK_CHMOD && !S_ISLNK(n->mode)) {
		if (fchmodat(AT_FDCWD, n->name, n->mode, 0)) {
			fprintf(stderr, "chmod %s: %s\n",
				n->name, strerror(errno));
			return -1;
		}
	}
	return 0;
}

int restore_fstree(tree_node_t *root, int flags)
{
	tree_node_t *n, *old_parent;

	/* make sure fstree_get_path() stops at this node */
	old_parent = root->parent;
	root->parent = NULL;

	if (S_ISDIR(root->mode)) {
		for (n = root->data.dir->children; n != NULL; n = n->next) {
			if (create_node(n, flags))
				return -1;
		}
	} else {
		if (create_node(root, flags))
			return -1;
	}

	root->parent = old_parent;
	return 0;
}

int update_tree_attribs(fstree_t *fs, tree_node_t *root, int flags)
{
	tree_node_t *n;

	if ((flags & (UNPACK_CHOWN | UNPACK_CHMOD | UNPACK_SET_TIMES)) == 0)
		return 0;

	if (S_ISDIR(root->mode)) {
		for (n = root->data.dir->children; n != NULL; n = n->next) {
			if (set_attribs(fs, n, flags))
				return -1;
		}
	} else {
		if (set_attribs(fs, root, flags))
			return -1;
	}

	return 0;
}