1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * Extra Boot Config
  4 * Masami Hiramatsu <mhiramat@kernel.org>
  5 */
  6
  7#define pr_fmt(fmt)    "bootconfig: " fmt
  8
  9#include <linux/bootconfig.h>
 10#include <linux/bug.h>
 11#include <linux/ctype.h>
 12#include <linux/errno.h>
 13#include <linux/kernel.h>
 14#include <linux/memblock.h>
 15#include <linux/printk.h>
 16#include <linux/string.h>
 17
 18/*
 19 * Extra Boot Config (XBC) is given as tree-structured ascii text of
 20 * key-value pairs on memory.
 21 * xbc_parse() parses the text to build a simple tree. Each tree node is
 22 * simply a key word or a value. A key node may have a next key node or/and
 23 * a child node (both key and value). A value node may have a next value
 24 * node (for array).
 25 */
 26
 27static struct xbc_node *xbc_nodes __initdata;
 28static int xbc_node_num __initdata;
 29static char *xbc_data __initdata;
 30static size_t xbc_data_size __initdata;
 31static struct xbc_node *last_parent __initdata;
 32static const char *xbc_err_msg __initdata;
 33static int xbc_err_pos __initdata;
 34static int open_brace[XBC_DEPTH_MAX] __initdata;
 35static int brace_index __initdata;
 36
 37static int __init xbc_parse_error(const char *msg, const char *p)
 38{
 39	xbc_err_msg = msg;
 40	xbc_err_pos = (int)(p - xbc_data);
 41
 42	return -EINVAL;
 43}
 44
 45/**
 46 * xbc_root_node() - Get the root node of extended boot config
 47 *
 48 * Return the address of root node of extended boot config. If the
 49 * extended boot config is not initiized, return NULL.
 50 */
 51struct xbc_node * __init xbc_root_node(void)
 52{
 53	if (unlikely(!xbc_data))
 54		return NULL;
 55
 56	return xbc_nodes;
 57}
 58
 59/**
 60 * xbc_node_index() - Get the index of XBC node
 61 * @node: A target node of getting index.
 62 *
 63 * Return the index number of @node in XBC node list.
 64 */
 65int __init xbc_node_index(struct xbc_node *node)
 66{
 67	return node - &xbc_nodes[0];
 68}
 69
 70/**
 71 * xbc_node_get_parent() - Get the parent XBC node
 72 * @node: An XBC node.
 73 *
 74 * Return the parent node of @node. If the node is top node of the tree,
 75 * return NULL.
 76 */
 77struct xbc_node * __init xbc_node_get_parent(struct xbc_node *node)
 78{
 79	return node->parent == XBC_NODE_MAX ? NULL : &xbc_nodes[node->parent];
 80}
 81
 82/**
 83 * xbc_node_get_child() - Get the child XBC node
 84 * @node: An XBC node.
 85 *
 86 * Return the first child node of @node. If the node has no child, return
 87 * NULL.
 88 */
 89struct xbc_node * __init xbc_node_get_child(struct xbc_node *node)
 90{
 91	return node->child ? &xbc_nodes[node->child] : NULL;
 92}
 93
 94/**
 95 * xbc_node_get_next() - Get the next sibling XBC node
 96 * @node: An XBC node.
 97 *
 98 * Return the NEXT sibling node of @node. If the node has no next sibling,
 99 * return NULL. Note that even if this returns NULL, it doesn't mean @node
100 * has no siblings. (You also has to check whether the parent's child node
101 * is @node or not.)
102 */
103struct xbc_node * __init xbc_node_get_next(struct xbc_node *node)
104{
105	return node->next ? &xbc_nodes[node->next] : NULL;
106}
107
108/**
109 * xbc_node_get_data() - Get the data of XBC node
110 * @node: An XBC node.
111 *
112 * Return the data (which is always a null terminated string) of @node.
113 * If the node has invalid data, warn and return NULL.
114 */
115const char * __init xbc_node_get_data(struct xbc_node *node)
116{
117	int offset = node->data & ~XBC_VALUE;
118
119	if (WARN_ON(offset >= xbc_data_size))
120		return NULL;
121
122	return xbc_data + offset;
123}
124
125static bool __init
126xbc_node_match_prefix(struct xbc_node *node, const char **prefix)
127{
128	const char *p = xbc_node_get_data(node);
129	int len = strlen(p);
130
131	if (strncmp(*prefix, p, len))
132		return false;
133
134	p = *prefix + len;
135	if (*p == '.')
136		p++;
137	else if (*p != '\0')
138		return false;
139	*prefix = p;
140
141	return true;
142}
143
144/**
145 * xbc_node_find_child() - Find a child node which matches given key
146 * @parent: An XBC node.
147 * @key: A key string.
148 *
149 * Search a node under @parent which matches @key. The @key can contain
150 * several words jointed with '.'. If @parent is NULL, this searches the
151 * node from whole tree. Return NULL if no node is matched.
152 */
153struct xbc_node * __init
154xbc_node_find_child(struct xbc_node *parent, const char *key)
155{
156	struct xbc_node *node;
157
158	if (parent)
159		node = xbc_node_get_subkey(parent);
160	else
161		node = xbc_root_node();
162
163	while (node && xbc_node_is_key(node)) {
164		if (!xbc_node_match_prefix(node, &key))
165			node = xbc_node_get_next(node);
166		else if (*key != '\0')
167			node = xbc_node_get_subkey(node);
168		else
169			break;
170	}
171
172	return node;
173}
174
175/**
176 * xbc_node_find_value() - Find a value node which matches given key
177 * @parent: An XBC node.
178 * @key: A key string.
179 * @vnode: A container pointer of found XBC node.
180 *
181 * Search a value node under @parent whose (parent) key node matches @key,
182 * store it in *@vnode, and returns the value string.
183 * The @key can contain several words jointed with '.'. If @parent is NULL,
184 * this searches the node from whole tree. Return the value string if a
185 * matched key found, return NULL if no node is matched.
186 * Note that this returns 0-length string and stores NULL in *@vnode if the
187 * key has no value. And also it will return the value of the first entry if
188 * the value is an array.
189 */
190const char * __init
191xbc_node_find_value(struct xbc_node *parent, const char *key,
192		    struct xbc_node **vnode)
193{
194	struct xbc_node *node = xbc_node_find_child(parent, key);
195
196	if (!node || !xbc_node_is_key(node))
197		return NULL;
198
199	node = xbc_node_get_child(node);
200	if (node && !xbc_node_is_value(node))
201		return NULL;
202
203	if (vnode)
204		*vnode = node;
205
206	return node ? xbc_node_get_data(node) : "";
207}
208
209/**
210 * xbc_node_compose_key_after() - Compose partial key string of the XBC node
211 * @root: Root XBC node
212 * @node: Target XBC node.
213 * @buf: A buffer to store the key.
214 * @size: The size of the @buf.
215 *
216 * Compose the partial key of the @node into @buf, which is starting right
217 * after @root (@root is not included.) If @root is NULL, this returns full
218 * key words of @node.
219 * Returns the total length of the key stored in @buf. Returns -EINVAL
220 * if @node is NULL or @root is not the ancestor of @node or @root is @node,
221 * or returns -ERANGE if the key depth is deeper than max depth.
222 * This is expected to be used with xbc_find_node() to list up all (child)
223 * keys under given key.
224 */
225int __init xbc_node_compose_key_after(struct xbc_node *root,
226				      struct xbc_node *node,
227				      char *buf, size_t size)
228{
229	u16 keys[XBC_DEPTH_MAX];
230	int depth = 0, ret = 0, total = 0;
231
232	if (!node || node == root)
233		return -EINVAL;
234
235	if (xbc_node_is_value(node))
236		node = xbc_node_get_parent(node);
237
238	while (node && node != root) {
239		keys[depth++] = xbc_node_index(node);
240		if (depth == XBC_DEPTH_MAX)
241			return -ERANGE;
242		node = xbc_node_get_parent(node);
243	}
244	if (!node && root)
245		return -EINVAL;
246
247	while (--depth >= 0) {
248		node = xbc_nodes + keys[depth];
249		ret = snprintf(buf, size, "%s%s", xbc_node_get_data(node),
250			       depth ? "." : "");
251		if (ret < 0)
252			return ret;
253		if (ret > size) {
254			size = 0;
255		} else {
256			size -= ret;
257			buf += ret;
258		}
259		total += ret;
260	}
261
262	return total;
263}
264
265/**
266 * xbc_node_find_next_leaf() - Find the next leaf node under given node
267 * @root: An XBC root node
268 * @node: An XBC node which starts from.
269 *
270 * Search the next leaf node (which means the terminal key node) of @node
271 * under @root node (including @root node itself).
272 * Return the next node or NULL if next leaf node is not found.
273 */
274struct xbc_node * __init xbc_node_find_next_leaf(struct xbc_node *root,
275						 struct xbc_node *node)
276{
277	struct xbc_node *next;
278
279	if (unlikely(!xbc_data))
280		return NULL;
281
282	if (!node) {	/* First try */
283		node = root;
284		if (!node)
285			node = xbc_nodes;
286	} else {
287		/* Leaf node may have a subkey */
288		next = xbc_node_get_subkey(node);
289		if (next) {
290			node = next;
291			goto found;
292		}
293
294		if (node == root)	/* @root was a leaf, no child node. */
295			return NULL;
296
297		while (!node->next) {
298			node = xbc_node_get_parent(node);
299			if (node == root)
300				return NULL;
301			/* User passed a node which is not uder parent */
302			if (WARN_ON(!node))
303				return NULL;
304		}
305		node = xbc_node_get_next(node);
306	}
307
308found:
309	while (node && !xbc_node_is_leaf(node))
310		node = xbc_node_get_child(node);
311
312	return node;
313}
314
315/**
316 * xbc_node_find_next_key_value() - Find the next key-value pair nodes
317 * @root: An XBC root node
318 * @leaf: A container pointer of XBC node which starts from.
319 *
320 * Search the next leaf node (which means the terminal key node) of *@leaf
321 * under @root node. Returns the value and update *@leaf if next leaf node
322 * is found, or NULL if no next leaf node is found.
323 * Note that this returns 0-length string if the key has no value, or
324 * the value of the first entry if the value is an array.
325 */
326const char * __init xbc_node_find_next_key_value(struct xbc_node *root,
327						 struct xbc_node **leaf)
328{
329	/* tip must be passed */
330	if (WARN_ON(!leaf))
331		return NULL;
332
333	*leaf = xbc_node_find_next_leaf(root, *leaf);
334	if (!*leaf)
335		return NULL;
336	if ((*leaf)->child)
337		return xbc_node_get_data(xbc_node_get_child(*leaf));
338	else
339		return "";	/* No value key */
340}
341
342/* XBC parse and tree build */
343
344static int __init xbc_init_node(struct xbc_node *node, char *data, u32 flag)
345{
346	unsigned long offset = data - xbc_data;
347
348	if (WARN_ON(offset >= XBC_DATA_MAX))
349		return -EINVAL;
350
351	node->data = (u16)offset | flag;
352	node->child = 0;
353	node->next = 0;
354
355	return 0;
356}
357
358static struct xbc_node * __init xbc_add_node(char *data, u32 flag)
359{
360	struct xbc_node *node;
361
362	if (xbc_node_num == XBC_NODE_MAX)
363		return NULL;
364
365	node = &xbc_nodes[xbc_node_num++];
366	if (xbc_init_node(node, data, flag) < 0)
367		return NULL;
368
369	return node;
370}
371
372static inline __init struct xbc_node *xbc_last_sibling(struct xbc_node *node)
373{
374	while (node->next)
375		node = xbc_node_get_next(node);
376
377	return node;
378}
379
380static inline __init struct xbc_node *xbc_last_child(struct xbc_node *node)
381{
382	while (node->child)
383		node = xbc_node_get_child(node);
384
385	return node;
386}
387
388static struct xbc_node * __init __xbc_add_sibling(char *data, u32 flag, bool head)
389{
390	struct xbc_node *sib, *node = xbc_add_node(data, flag);
391
392	if (node) {
393		if (!last_parent) {
394			/* Ignore @head in this case */
395			node->parent = XBC_NODE_MAX;
396			sib = xbc_last_sibling(xbc_nodes);
397			sib->next = xbc_node_index(node);
398		} else {
399			node->parent = xbc_node_index(last_parent);
400			if (!last_parent->child || head) {
401				node->next = last_parent->child;
402				last_parent->child = xbc_node_index(node);
403			} else {
404				sib = xbc_node_get_child(last_parent);
405				sib = xbc_last_sibling(sib);
406				sib->next = xbc_node_index(node);
407			}
408		}
409	} else
410		xbc_parse_error("Too many nodes", data);
411
412	return node;
413}
414
415static inline struct xbc_node * __init xbc_add_sibling(char *data, u32 flag)
416{
417	return __xbc_add_sibling(data, flag, false);
418}
419
420static inline struct xbc_node * __init xbc_add_head_sibling(char *data, u32 flag)
421{
422	return __xbc_add_sibling(data, flag, true);
423}
424
425static inline __init struct xbc_node *xbc_add_child(char *data, u32 flag)
426{
427	struct xbc_node *node = xbc_add_sibling(data, flag);
428
429	if (node)
430		last_parent = node;
431
432	return node;
433}
434
435static inline __init bool xbc_valid_keyword(char *key)
436{
437	if (key[0] == '\0')
438		return false;
439
440	while (isalnum(*key) || *key == '-' || *key == '_')
441		key++;
442
443	return *key == '\0';
444}
445
446static char *skip_comment(char *p)
447{
448	char *ret;
449
450	ret = strchr(p, '\n');
451	if (!ret)
452		ret = p + strlen(p);
453	else
454		ret++;
455
456	return ret;
457}
458
459static char *skip_spaces_until_newline(char *p)
460{
461	while (isspace(*p) && *p != '\n')
462		p++;
463	return p;
464}
465
466static int __init __xbc_open_brace(char *p)
467{
468	/* Push the last key as open brace */
469	open_brace[brace_index++] = xbc_node_index(last_parent);
470	if (brace_index >= XBC_DEPTH_MAX)
471		return xbc_parse_error("Exceed max depth of braces", p);
472
473	return 0;
474}
475
476static int __init __xbc_close_brace(char *p)
477{
478	brace_index--;
479	if (!last_parent || brace_index < 0 ||
480	    (open_brace[brace_index] != xbc_node_index(last_parent)))
481		return xbc_parse_error("Unexpected closing brace", p);
482
483	if (brace_index == 0)
484		last_parent = NULL;
485	else
486		last_parent = &xbc_nodes[open_brace[brace_index - 1]];
487
488	return 0;
489}
490
491/*
492 * Return delimiter or error, no node added. As same as lib/cmdline.c,
493 * you can use " around spaces, but can't escape " for value.
494 */
495static int __init __xbc_parse_value(char **__v, char **__n)
496{
497	char *p, *v = *__v;
498	int c, quotes = 0;
499
500	v = skip_spaces(v);
501	while (*v == '#') {
502		v = skip_comment(v);
503		v = skip_spaces(v);
504	}
505	if (*v == '"' || *v == '\'') {
506		quotes = *v;
507		v++;
508	}
509	p = v - 1;
510	while ((c = *++p)) {
511		if (!isprint(c) && !isspace(c))
512			return xbc_parse_error("Non printable value", p);
513		if (quotes) {
514			if (c != quotes)
515				continue;
516			quotes = 0;
517			*p++ = '\0';
518			p = skip_spaces_until_newline(p);
519			c = *p;
520			if (c && !strchr(",;\n#}", c))
521				return xbc_parse_error("No value delimiter", p);
522			if (*p)
523				p++;
524			break;
525		}
526		if (strchr(",;\n#}", c)) {
527			*p++ = '\0';
528			v = strim(v);
529			break;
530		}
531	}
532	if (quotes)
533		return xbc_parse_error("No closing quotes", p);
534	if (c == '#') {
535		p = skip_comment(p);
536		c = '\n';	/* A comment must be treated as a newline */
537	}
538	*__n = p;
539	*__v = v;
540
541	return c;
542}
543
544static int __init xbc_parse_array(char **__v)
545{
546	struct xbc_node *node;
547	char *next;
548	int c = 0;
549
550	if (last_parent->child)
551		last_parent = xbc_node_get_child(last_parent);
552
553	do {
554		c = __xbc_parse_value(__v, &next);
555		if (c < 0)
556			return c;
557
558		node = xbc_add_child(*__v, XBC_VALUE);
559		if (!node)
560			return -ENOMEM;
561		*__v = next;
562	} while (c == ',');
563	node->child = 0;
564
565	return c;
566}
567
568static inline __init
569struct xbc_node *find_match_node(struct xbc_node *node, char *k)
570{
571	while (node) {
572		if (!strcmp(xbc_node_get_data(node), k))
573			break;
574		node = xbc_node_get_next(node);
575	}
576	return node;
577}
578
579static int __init __xbc_add_key(char *k)
580{
581	struct xbc_node *node, *child;
582
583	if (!xbc_valid_keyword(k))
584		return xbc_parse_error("Invalid keyword", k);
585
586	if (unlikely(xbc_node_num == 0))
587		goto add_node;
588
589	if (!last_parent)	/* the first level */
590		node = find_match_node(xbc_nodes, k);
591	else {
592		child = xbc_node_get_child(last_parent);
593		/* Since the value node is the first child, skip it. */
594		if (child && xbc_node_is_value(child))
595			child = xbc_node_get_next(child);
596		node = find_match_node(child, k);
597	}
598
599	if (node)
600		last_parent = node;
601	else {
602add_node:
603		node = xbc_add_child(k, XBC_KEY);
604		if (!node)
605			return -ENOMEM;
606	}
607	return 0;
608}
609
610static int __init __xbc_parse_keys(char *k)
611{
612	char *p;
613	int ret;
614
615	k = strim(k);
616	while ((p = strchr(k, '.'))) {
617		*p++ = '\0';
618		ret = __xbc_add_key(k);
619		if (ret)
620			return ret;
621		k = p;
622	}
623
624	return __xbc_add_key(k);
625}
626
627static int __init xbc_parse_kv(char **k, char *v, int op)
628{
629	struct xbc_node *prev_parent = last_parent;
630	struct xbc_node *child;
631	char *next;
632	int c, ret;
633
634	ret = __xbc_parse_keys(*k);
635	if (ret)
636		return ret;
637
 
 
 
 
 
 
 
 
638	c = __xbc_parse_value(&v, &next);
639	if (c < 0)
640		return c;
641
642	child = xbc_node_get_child(last_parent);
643	if (child && xbc_node_is_value(child)) {
644		if (op == '=')
645			return xbc_parse_error("Value is redefined", v);
646		if (op == ':') {
647			unsigned short nidx = child->next;
648
649			xbc_init_node(child, v, XBC_VALUE);
650			child->next = nidx;	/* keep subkeys */
651			goto array;
652		}
653		/* op must be '+' */
654		last_parent = xbc_last_child(child);
655	}
656	/* The value node should always be the first child */
657	if (!xbc_add_head_sibling(v, XBC_VALUE))
658		return -ENOMEM;
659
660array:
661	if (c == ',') {	/* Array */
662		c = xbc_parse_array(&next);
663		if (c < 0)
664			return c;
665	}
666
667	last_parent = prev_parent;
668
669	if (c == '}') {
670		ret = __xbc_close_brace(next - 1);
671		if (ret < 0)
672			return ret;
673	}
674
675	*k = next;
676
677	return 0;
678}
679
680static int __init xbc_parse_key(char **k, char *n)
681{
682	struct xbc_node *prev_parent = last_parent;
683	int ret;
684
685	*k = strim(*k);
686	if (**k != '\0') {
687		ret = __xbc_parse_keys(*k);
688		if (ret)
689			return ret;
690		last_parent = prev_parent;
691	}
692	*k = n;
693
694	return 0;
695}
696
697static int __init xbc_open_brace(char **k, char *n)
698{
699	int ret;
700
701	ret = __xbc_parse_keys(*k);
702	if (ret)
703		return ret;
704	*k = n;
705
706	return __xbc_open_brace(n - 1);
707}
708
709static int __init xbc_close_brace(char **k, char *n)
710{
711	int ret;
712
713	ret = xbc_parse_key(k, n);
714	if (ret)
715		return ret;
716	/* k is updated in xbc_parse_key() */
717
718	return __xbc_close_brace(n - 1);
719}
720
721static int __init xbc_verify_tree(void)
722{
723	int i, depth, len, wlen;
724	struct xbc_node *n, *m;
725
726	/* Brace closing */
727	if (brace_index) {
728		n = &xbc_nodes[open_brace[brace_index]];
729		return xbc_parse_error("Brace is not closed",
730					xbc_node_get_data(n));
731	}
732
733	/* Empty tree */
734	if (xbc_node_num == 0) {
735		xbc_parse_error("Empty config", xbc_data);
736		return -ENOENT;
737	}
738
739	for (i = 0; i < xbc_node_num; i++) {
740		if (xbc_nodes[i].next > xbc_node_num) {
741			return xbc_parse_error("No closing brace",
742				xbc_node_get_data(xbc_nodes + i));
743		}
744	}
745
746	/* Key tree limitation check */
747	n = &xbc_nodes[0];
748	depth = 1;
749	len = 0;
750
751	while (n) {
752		wlen = strlen(xbc_node_get_data(n)) + 1;
753		len += wlen;
754		if (len > XBC_KEYLEN_MAX)
755			return xbc_parse_error("Too long key length",
756				xbc_node_get_data(n));
757
758		m = xbc_node_get_child(n);
759		if (m && xbc_node_is_key(m)) {
760			n = m;
761			depth++;
762			if (depth > XBC_DEPTH_MAX)
763				return xbc_parse_error("Too many key words",
764						xbc_node_get_data(n));
765			continue;
766		}
767		len -= wlen;
768		m = xbc_node_get_next(n);
769		while (!m) {
770			n = xbc_node_get_parent(n);
771			if (!n)
772				break;
773			len -= strlen(xbc_node_get_data(n)) + 1;
774			depth--;
775			m = xbc_node_get_next(n);
776		}
777		n = m;
778	}
779
780	return 0;
781}
782
783/**
784 * xbc_destroy_all() - Clean up all parsed bootconfig
785 *
786 * This clears all data structures of parsed bootconfig on memory.
787 * If you need to reuse xbc_init() with new boot config, you can
788 * use this.
789 */
790void __init xbc_destroy_all(void)
791{
792	xbc_data = NULL;
793	xbc_data_size = 0;
794	xbc_node_num = 0;
795	memblock_free(__pa(xbc_nodes), sizeof(struct xbc_node) * XBC_NODE_MAX);
796	xbc_nodes = NULL;
797	brace_index = 0;
798}
799
800/**
801 * xbc_init() - Parse given XBC file and build XBC internal tree
802 * @buf: boot config text
803 * @emsg: A pointer of const char * to store the error message
804 * @epos: A pointer of int to store the error position
805 *
806 * This parses the boot config text in @buf. @buf must be a
807 * null terminated string and smaller than XBC_DATA_MAX.
808 * Return the number of stored nodes (>0) if succeeded, or -errno
809 * if there is any error.
810 * In error cases, @emsg will be updated with an error message and
811 * @epos will be updated with the error position which is the byte offset
812 * of @buf. If the error is not a parser error, @epos will be -1.
813 */
814int __init xbc_init(char *buf, const char **emsg, int *epos)
815{
816	char *p, *q;
817	int ret, c;
818
819	if (epos)
820		*epos = -1;
821
822	if (xbc_data) {
823		if (emsg)
824			*emsg = "Bootconfig is already initialized";
825		return -EBUSY;
826	}
827
828	ret = strlen(buf);
829	if (ret > XBC_DATA_MAX - 1 || ret == 0) {
830		if (emsg)
831			*emsg = ret ? "Config data is too big" :
832				"Config data is empty";
833		return -ERANGE;
834	}
835
836	xbc_nodes = memblock_alloc(sizeof(struct xbc_node) * XBC_NODE_MAX,
837				   SMP_CACHE_BYTES);
838	if (!xbc_nodes) {
839		if (emsg)
840			*emsg = "Failed to allocate bootconfig nodes";
841		return -ENOMEM;
842	}
843	memset(xbc_nodes, 0, sizeof(struct xbc_node) * XBC_NODE_MAX);
844	xbc_data = buf;
845	xbc_data_size = ret + 1;
846	last_parent = NULL;
847
848	p = buf;
849	do {
850		q = strpbrk(p, "{}=+;:\n#");
851		if (!q) {
852			p = skip_spaces(p);
853			if (*p != '\0')
854				ret = xbc_parse_error("No delimiter", p);
855			break;
856		}
857
858		c = *q;
859		*q++ = '\0';
860		switch (c) {
861		case ':':
862		case '+':
863			if (*q++ != '=') {
864				ret = xbc_parse_error(c == '+' ?
865						"Wrong '+' operator" :
866						"Wrong ':' operator",
867							q - 2);
868				break;
869			}
870			fallthrough;
871		case '=':
872			ret = xbc_parse_kv(&p, q, c);
873			break;
874		case '{':
875			ret = xbc_open_brace(&p, q);
876			break;
877		case '#':
878			q = skip_comment(q);
879			fallthrough;
880		case ';':
881		case '\n':
882			ret = xbc_parse_key(&p, q);
883			break;
884		case '}':
885			ret = xbc_close_brace(&p, q);
886			break;
887		}
888	} while (!ret);
889
890	if (!ret)
891		ret = xbc_verify_tree();
892
893	if (ret < 0) {
894		if (epos)
895			*epos = xbc_err_pos;
896		if (emsg)
897			*emsg = xbc_err_msg;
898		xbc_destroy_all();
899	} else
900		ret = xbc_node_num;
901
902	return ret;
903}
904
905/**
906 * xbc_debug_dump() - Dump current XBC node list
907 *
908 * Dump the current XBC node list on printk buffer for debug.
909 */
910void __init xbc_debug_dump(void)
911{
912	int i;
913
914	for (i = 0; i < xbc_node_num; i++) {
915		pr_debug("[%d] %s (%s) .next=%d, .child=%d .parent=%d\n", i,
916			xbc_node_get_data(xbc_nodes + i),
917			xbc_node_is_value(xbc_nodes + i) ? "value" : "key",
918			xbc_nodes[i].next, xbc_nodes[i].child,
919			xbc_nodes[i].parent);
920	}
921}