[deliverable/linux.git] / drivers / staging / lustre / lnet / libcfs / libcfs_string.c

/*
 * GPL HEADER START
 *
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 only,
 * as published by the Free Software Foundation.
 *
 * This program 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 version 2 for more details (a copy is included
 * in the LICENSE file that accompanied this code).
 *
 * You should have received a copy of the GNU General Public License
 * version 2 along with this program; If not, see
 * http://www.gnu.org/licenses/gpl-2.0.html
 *
 * GPL HEADER END
 */
/*
 * Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
 * Use is subject to license terms.
 *
 * Copyright (c) 2012, 2015 Intel Corporation.
 */
/*
 * This file is part of Lustre, http://www.lustre.org/
 * Lustre is a trademark of Sun Microsystems, Inc.
 *
 * String manipulation functions.
 *
 * libcfs/libcfs/libcfs_string.c
 *
 * Author: Nathan Rutman <nathan.rutman@sun.com>
 */

#include "../../include/linux/libcfs/libcfs.h"

/* Convert a text string to a bitmask */
int cfs_str2mask(const char *str, const char *(*bit2str)(int bit),
		 int *oldmask, int minmask, int allmask)
{
	const char *debugstr;
	char op = '\0';
	int newmask = minmask, i, len, found = 0;

	/* <str> must be a list of tokens separated by whitespace
	 * and optionally an operator ('+' or '-').  If an operator
	 * appears first in <str>, '*oldmask' is used as the starting point
	 * (relative), otherwise minmask is used (absolute).  An operator
	 * applies to all following tokens up to the next operator.
	 */
	while (*str != '\0') {
		while (isspace(*str))
			str++;
		if (*str == '\0')
			break;
		if (*str == '+' || *str == '-') {
			op = *str++;
			if (!found)
				/* only if first token is relative */
				newmask = *oldmask;
			while (isspace(*str))
				str++;
			if (*str == '\0')  /* trailing op */
				return -EINVAL;
		}

		/* find token length */
		len = 0;
		while (str[len] != '\0' && !isspace(str[len]) &&
		       str[len] != '+' && str[len] != '-')
			len++;

		/* match token */
		found = 0;
		for (i = 0; i < 32; i++) {
			debugstr = bit2str(i);
			if (debugstr && strlen(debugstr) == len &&
			    strncasecmp(str, debugstr, len) == 0) {
				if (op == '-')
					newmask &= ~(1 << i);
				else
					newmask |= (1 << i);
				found = 1;
				break;
			}
		}
		if (!found && len == 3 &&
		    (strncasecmp(str, "ALL", len) == 0)) {
			if (op == '-')
				newmask = minmask;
			else
				newmask = allmask;
			found = 1;
		}
		if (!found) {
			CWARN("unknown mask '%.*s'.\n"
			      "mask usage: [+|-]<all|type> ...\n", len, str);
			return -EINVAL;
		}
		str += len;
	}

	*oldmask = newmask;
	return 0;
}

/* get the first string out of @str */
char *cfs_firststr(char *str, size_t size)
{
	size_t i = 0;
	char  *end;

	/* trim leading spaces */
	while (i < size && *str && isspace(*str)) {
		++i;
		++str;
	}

	/* string with all spaces */
	if (*str == '\0')
		goto out;

	end = str;
	while (i < size && *end != '\0' && !isspace(*end)) {
		++i;
		++end;
	}

	*end = '\0';
out:
	return str;
}
EXPORT_SYMBOL(cfs_firststr);

char *
cfs_trimwhite(char *str)
{
	char *end;

	while (isspace(*str))
		str++;

	end = str + strlen(str);
	while (end > str) {
		if (!isspace(end[-1]))
			break;
		end--;
	}

	*end = 0;
	return str;
}
EXPORT_SYMBOL(cfs_trimwhite);

/**
 * Extracts tokens from strings.
 *
 * Looks for \a delim in string \a next, sets \a res to point to
 * substring before the delimiter, sets \a next right after the found
 * delimiter.
 *
 * \retval 1 if \a res points to a string of non-whitespace characters
 * \retval 0 otherwise
 */
int
cfs_gettok(struct cfs_lstr *next, char delim, struct cfs_lstr *res)
{
	char *end;

	if (!next->ls_str)
		return 0;

	/* skip leading white spaces */
	while (next->ls_len) {
		if (!isspace(*next->ls_str))
			break;
		next->ls_str++;
		next->ls_len--;
	}

	if (next->ls_len == 0) /* whitespaces only */
		return 0;

	if (*next->ls_str == delim) {
		/* first non-writespace is the delimiter */
		return 0;
	}

	res->ls_str = next->ls_str;
	end = memchr(next->ls_str, delim, next->ls_len);
	if (!end) {
		/* there is no the delimeter in the string */
		end = next->ls_str + next->ls_len;
		next->ls_str = NULL;
	} else {
		next->ls_str = end + 1;
		next->ls_len -= (end - res->ls_str + 1);
	}

	/* skip ending whitespaces */
	while (--end != res->ls_str) {
		if (!isspace(*end))
			break;
	}

	res->ls_len = end - res->ls_str + 1;
	return 1;
}
EXPORT_SYMBOL(cfs_gettok);

/**
 * Converts string to integer.
 *
 * Accepts decimal and hexadecimal number recordings.
 *
 * \retval 1 if first \a nob chars of \a str convert to decimal or
 * hexadecimal integer in the range [\a min, \a max]
 * \retval 0 otherwise
 */
int
cfs_str2num_check(char *str, int nob, unsigned *num,
		  unsigned min, unsigned max)
{
	bool all_numbers = true;
	char *endp, cache;
	int rc;

	/**
	 * kstrouint can only handle strings composed
	 * of only numbers. We need to scan the string
	 * passed in for the first non-digit character
	 * and end the string at that location. If we
	 * don't find any non-digit character we still
	 * need to place a '\0' at position nob since
	 * we are not interested in the rest of the
	 * string which is longer than nob in size.
	 * After we are done the character at the
	 * position we placed '\0' must be restored.
	 */
	for (endp = str; endp < str + nob; endp++) {
		if (!isdigit(*endp)) {
			all_numbers = false;
			break;
		}
	}
	cache = *endp;
	*endp = '\0';

	rc = kstrtouint(str, 10, num);
	*endp = cache;
	if (rc || !all_numbers)
		return 0;

	return (*num >= min && *num <= max);
}
EXPORT_SYMBOL(cfs_str2num_check);

/**
 * Parses \<range_expr\> token of the syntax. If \a bracketed is false,
 * \a src should only have a single token which can be \<number\> or  \*
 *
 * \retval pointer to allocated range_expr and initialized
 * range_expr::re_lo, range_expr::re_hi and range_expr:re_stride if \a
 `* src parses to
 * \<number\> |
 * \<number\> '-' \<number\> |
 * \<number\> '-' \<number\> '/' \<number\>
 * \retval 0 will be returned if it can be parsed, otherwise -EINVAL or
 * -ENOMEM will be returned.
 */
static int
cfs_range_expr_parse(struct cfs_lstr *src, unsigned min, unsigned max,
		     int bracketed, struct cfs_range_expr **expr)
{
	struct cfs_range_expr	*re;
	struct cfs_lstr		tok;

	LIBCFS_ALLOC(re, sizeof(*re));
	if (!re)
		return -ENOMEM;

	if (src->ls_len == 1 && src->ls_str[0] == '*') {
		re->re_lo = min;
		re->re_hi = max;
		re->re_stride = 1;
		goto out;
	}

	if (cfs_str2num_check(src->ls_str, src->ls_len,
			      &re->re_lo, min, max)) {
		/* <number> is parsed */
		re->re_hi = re->re_lo;
		re->re_stride = 1;
		goto out;
	}

	if (!bracketed || !cfs_gettok(src, '-', &tok))
		goto failed;

	if (!cfs_str2num_check(tok.ls_str, tok.ls_len,
			       &re->re_lo, min, max))
		goto failed;

	/* <number> - */
	if (cfs_str2num_check(src->ls_str, src->ls_len,
			      &re->re_hi, min, max)) {
		/* <number> - <number> is parsed */
		re->re_stride = 1;
		goto out;
	}

	/* go to check <number> '-' <number> '/' <number> */
	if (cfs_gettok(src, '/', &tok)) {
		if (!cfs_str2num_check(tok.ls_str, tok.ls_len,
				       &re->re_hi, min, max))
			goto failed;

		/* <number> - <number> / ... */
		if (cfs_str2num_check(src->ls_str, src->ls_len,
				      &re->re_stride, min, max)) {
			/* <number> - <number> / <number> is parsed */
			goto out;
		}
	}

 out:
	*expr = re;
	return 0;

 failed:
	LIBCFS_FREE(re, sizeof(*re));
	return -EINVAL;
}

/**
 * Print the range expression \a re into specified \a buffer.
 * If \a bracketed is true, expression does not need additional
 * brackets.
 *
 * \retval number of characters written
 */
static int
cfs_range_expr_print(char *buffer, int count, struct cfs_range_expr *expr,
		     bool bracketed)
{
	int i;
	char s[] = "[";
	char e[] = "]";

	if (bracketed) {
		s[0] = '\0';
		e[0] = '\0';
	}

	if (expr->re_lo == expr->re_hi)
		i = scnprintf(buffer, count, "%u", expr->re_lo);
	else if (expr->re_stride == 1)
		i = scnprintf(buffer, count, "%s%u-%u%s",
			      s, expr->re_lo, expr->re_hi, e);
	else
		i = scnprintf(buffer, count, "%s%u-%u/%u%s",
			      s, expr->re_lo, expr->re_hi, expr->re_stride, e);
	return i;
}

/**
 * Print a list of range expressions (\a expr_list) into specified \a buffer.
 * If the list contains several expressions, separate them with comma
 * and surround the list with brackets.
 *
 * \retval number of characters written
 */
int
cfs_expr_list_print(char *buffer, int count, struct cfs_expr_list *expr_list)
{
	struct cfs_range_expr *expr;
	int i = 0, j = 0;
	int numexprs = 0;

	if (count <= 0)
		return 0;

	list_for_each_entry(expr, &expr_list->el_exprs, re_link)
		numexprs++;

	if (numexprs > 1)
		i += scnprintf(buffer + i, count - i, "[");

	list_for_each_entry(expr, &expr_list->el_exprs, re_link) {
		if (j++ != 0)
			i += scnprintf(buffer + i, count - i, ",");
		i += cfs_range_expr_print(buffer + i, count - i, expr,
					  numexprs > 1);
	}

	if (numexprs > 1)
		i += scnprintf(buffer + i, count - i, "]");

	return i;
}
EXPORT_SYMBOL(cfs_expr_list_print);

/**
 * Matches value (\a value) against ranges expression list \a expr_list.
 *
 * \retval 1 if \a value matches
 * \retval 0 otherwise
 */
int
cfs_expr_list_match(__u32 value, struct cfs_expr_list *expr_list)
{
	struct cfs_range_expr	*expr;

	list_for_each_entry(expr, &expr_list->el_exprs, re_link) {
		if (value >= expr->re_lo && value <= expr->re_hi &&
		    ((value - expr->re_lo) % expr->re_stride) == 0)
			return 1;
	}

	return 0;
}
EXPORT_SYMBOL(cfs_expr_list_match);

/**
 * Convert express list (\a expr_list) to an array of all matched values
 *
 * \retval N N is total number of all matched values
 * \retval 0 if expression list is empty
 * \retval < 0 for failure
 */
int
cfs_expr_list_values(struct cfs_expr_list *expr_list, int max, __u32 **valpp)
{
	struct cfs_range_expr	*expr;
	__u32			*val;
	int			count = 0;
	int			i;

	list_for_each_entry(expr, &expr_list->el_exprs, re_link) {
		for (i = expr->re_lo; i <= expr->re_hi; i++) {
			if (((i - expr->re_lo) % expr->re_stride) == 0)
				count++;
		}
	}

	if (count == 0) /* empty expression list */
		return 0;

	if (count > max) {
		CERROR("Number of values %d exceeds max allowed %d\n",
		       max, count);
		return -EINVAL;
	}

	LIBCFS_ALLOC(val, sizeof(val[0]) * count);
	if (!val)
		return -ENOMEM;

	count = 0;
	list_for_each_entry(expr, &expr_list->el_exprs, re_link) {
		for (i = expr->re_lo; i <= expr->re_hi; i++) {
			if (((i - expr->re_lo) % expr->re_stride) == 0)
				val[count++] = i;
		}
	}

	*valpp = val;
	return count;
}
EXPORT_SYMBOL(cfs_expr_list_values);

/**
 * Frees cfs_range_expr structures of \a expr_list.
 *
 * \retval none
 */
void
cfs_expr_list_free(struct cfs_expr_list *expr_list)
{
	while (!list_empty(&expr_list->el_exprs)) {
		struct cfs_range_expr *expr;

		expr = list_entry(expr_list->el_exprs.next,
				  struct cfs_range_expr, re_link);
		list_del(&expr->re_link);
		LIBCFS_FREE(expr, sizeof(*expr));
	}

	LIBCFS_FREE(expr_list, sizeof(*expr_list));
}
EXPORT_SYMBOL(cfs_expr_list_free);

/**
 * Parses \<cfs_expr_list\> token of the syntax.
 *
 * \retval 0 if \a str parses to \<number\> | \<expr_list\>
 * \retval -errno otherwise
 */
int
cfs_expr_list_parse(char *str, int len, unsigned min, unsigned max,
		    struct cfs_expr_list **elpp)
{
	struct cfs_expr_list	*expr_list;
	struct cfs_range_expr	*expr;
	struct cfs_lstr		src;
	int			rc;

	LIBCFS_ALLOC(expr_list, sizeof(*expr_list));
	if (!expr_list)
		return -ENOMEM;

	src.ls_str = str;
	src.ls_len = len;

	INIT_LIST_HEAD(&expr_list->el_exprs);

	if (src.ls_str[0] == '[' &&
	    src.ls_str[src.ls_len - 1] == ']') {
		src.ls_str++;
		src.ls_len -= 2;

		rc = -EINVAL;
		while (src.ls_str) {
			struct cfs_lstr tok;

			if (!cfs_gettok(&src, ',', &tok)) {
				rc = -EINVAL;
				break;
			}

			rc = cfs_range_expr_parse(&tok, min, max, 1, &expr);
			if (rc != 0)
				break;

			list_add_tail(&expr->re_link, &expr_list->el_exprs);
		}
	} else {
		rc = cfs_range_expr_parse(&src, min, max, 0, &expr);
		if (rc == 0)
			list_add_tail(&expr->re_link, &expr_list->el_exprs);
	}

	if (rc != 0)
		cfs_expr_list_free(expr_list);
	else
		*elpp = expr_list;

	return rc;
}
EXPORT_SYMBOL(cfs_expr_list_parse);

/**
 * Frees cfs_expr_list structures of \a list.
 *
 * For each struct cfs_expr_list structure found on \a list it frees
 * range_expr list attached to it and frees the cfs_expr_list itself.
 *
 * \retval none
 */
void
cfs_expr_list_free_list(struct list_head *list)
{
	struct cfs_expr_list *el;

	while (!list_empty(list)) {
		el = list_entry(list->next, struct cfs_expr_list, el_link);
		list_del(&el->el_link);
		cfs_expr_list_free(el);
	}
}
EXPORT_SYMBOL(cfs_expr_list_free_list);
Commit	Line	Data
d7e09d03 PT	1	/*
	2	* GPL HEADER START
	3	*
	4	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License version 2 only,
	8	* as published by the Free Software Foundation.
	9	*
	10	* This program is distributed in the hope that it will be useful, but
	11	* WITHOUT ANY WARRANTY; without even the implied warranty of
	12	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	13	* General Public License version 2 for more details (a copy is included
	14	* in the LICENSE file that accompanied this code).
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* version 2 along with this program; If not, see
6a5b99a4	18	* http://www.gnu.org/licenses/gpl-2.0.html
d7e09d03	19	*
d7e09d03 PT	20	* GPL HEADER END
	21	*/
	22	/*
	23	* Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
	24	* Use is subject to license terms.
	25	*
1dc563a6	26	* Copyright (c) 2012, 2015 Intel Corporation.
d7e09d03 PT	27	*/
	28	/*
	29	* This file is part of Lustre, http://www.lustre.org/
	30	* Lustre is a trademark of Sun Microsystems, Inc.
	31	*
	32	* String manipulation functions.
	33	*
	34	* libcfs/libcfs/libcfs_string.c
	35	*
	36	* Author: Nathan Rutman <nathan.rutman@sun.com>
	37	*/
	38
9fdaf8c0	39	#include "../../include/linux/libcfs/libcfs.h"
d7e09d03	40
d7e09d03 PT	41	/* Convert a text string to a bitmask */
	42	int cfs_str2mask(const char str, const char (*bit2str)(int bit),
	43	int *oldmask, int minmask, int allmask)
	44	{
	45	const char *debugstr;
3f9773a5	46	char op = '\0';
d7e09d03	47	int newmask = minmask, i, len, found = 0;
d7e09d03 PT	48
	49	/* <str> must be a list of tokens separated by whitespace
	50	* and optionally an operator ('+' or '-'). If an operator
	51	* appears first in <str>, '*oldmask' is used as the starting point
	52	* (relative), otherwise minmask is used (absolute). An operator
a3fbcb3c OD	53	* applies to all following tokens up to the next operator.
a3fbcb3c OD	54	*/
3f9773a5	55	while (*str != '\0') {
d7e09d03 PT	56	while (isspace(*str))
d7e09d03 PT	57	str++;
3f9773a5	58	if (*str == '\0')
d7e09d03 PT	59	break;
	60	if (str == '+' \|\| str == '-') {
	61	op = *str++;
	62	if (!found)
	63	/* only if first token is relative */
	64	newmask = *oldmask;
	65	while (isspace(*str))
	66	str++;
3f9773a5	67	if (str == '\0') / trailing op */
d7e09d03 PT	68	return -EINVAL;
	69	}
	70
	71	/* find token length */
3f9773a5 MT	72	len = 0;
	73	while (str[len] != '\0' && !isspace(str[len]) &&
	74	str[len] != '+' && str[len] != '-')
	75	len++;
d7e09d03 PT	76
	77	/* match token */
	78	found = 0;
	79	for (i = 0; i < 32; i++) {
	80	debugstr = bit2str(i);
15d9f520	81	if (debugstr && strlen(debugstr) == len &&
7a724582	82	strncasecmp(str, debugstr, len) == 0) {
d7e09d03 PT	83	if (op == '-')
	84	newmask &= ~(1 << i);
	85	else
	86	newmask \|= (1 << i);
	87	found = 1;
	88	break;
	89	}
	90	}
	91	if (!found && len == 3 &&
7a724582	92	(strncasecmp(str, "ALL", len) == 0)) {
d7e09d03 PT	93	if (op == '-')
	94	newmask = minmask;
	95	else
	96	newmask = allmask;
	97	found = 1;
	98	}
	99	if (!found) {
	100	CWARN("unknown mask '%.*s'.\n"
	101	"mask usage: [+\|-]<all\|type> ...\n", len, str);
	102	return -EINVAL;
	103	}
	104	str += len;
	105	}
	106
	107	*oldmask = newmask;
	108	return 0;
	109	}
d7e09d03	110
d7e09d03 PT	111	/* get the first string out of @str */
	112	char cfs_firststr(char str, size_t size)
	113	{
	114	size_t i = 0;
	115	char *end;
	116
	117	/* trim leading spaces */
	118	while (i < size && str && isspace(str)) {
	119	++i;
	120	++str;
	121	}
	122
	123	/* string with all spaces */
	124	if (*str == '\0')
	125	goto out;
	126
	127	end = str;
	128	while (i < size && end != '\0' && !isspace(end)) {
	129	++i;
	130	++end;
	131	}
	132
51566472	133	*end = '\0';
d7e09d03 PT	134	out:
	135	return str;
	136	}
	137	EXPORT_SYMBOL(cfs_firststr);
	138
	139	char *
	140	cfs_trimwhite(char *str)
	141	{
	142	char *end;
	143
e525a681	144	while (isspace(*str))
d7e09d03 PT	145	str++;
	146
	147	end = str + strlen(str);
	148	while (end > str) {
e525a681	149	if (!isspace(end[-1]))
d7e09d03 PT	150	break;
	151	end--;
	152	}
	153
	154	*end = 0;
	155	return str;
	156	}
	157	EXPORT_SYMBOL(cfs_trimwhite);
	158
	159	/**
	160	* Extracts tokens from strings.
	161	*
	162	* Looks for \a delim in string \a next, sets \a res to point to
	163	* substring before the delimiter, sets \a next right after the found
	164	* delimiter.
	165	*
	166	* \retval 1 if \a res points to a string of non-whitespace characters
	167	* \retval 0 otherwise
	168	*/
	169	int
	170	cfs_gettok(struct cfs_lstr next, char delim, struct cfs_lstr res)
	171	{
	172	char *end;
	173
15d9f520	174	if (!next->ls_str)
d7e09d03 PT	175	return 0;
	176
	177	/* skip leading white spaces */
	178	while (next->ls_len) {
e525a681	179	if (!isspace(*next->ls_str))
d7e09d03 PT	180	break;
	181	next->ls_str++;
	182	next->ls_len--;
	183	}
	184
	185	if (next->ls_len == 0) /* whitespaces only */
	186	return 0;
	187
	188	if (*next->ls_str == delim) {
	189	/* first non-writespace is the delimiter */
	190	return 0;
	191	}
	192
	193	res->ls_str = next->ls_str;
	194	end = memchr(next->ls_str, delim, next->ls_len);
15d9f520	195	if (!end) {
d7e09d03 PT	196	/* there is no the delimeter in the string */
	197	end = next->ls_str + next->ls_len;
	198	next->ls_str = NULL;
	199	} else {
	200	next->ls_str = end + 1;
	201	next->ls_len -= (end - res->ls_str + 1);
	202	}
	203
	204	/* skip ending whitespaces */
	205	while (--end != res->ls_str) {
e525a681	206	if (!isspace(*end))
d7e09d03 PT	207	break;
	208	}
	209
	210	res->ls_len = end - res->ls_str + 1;
	211	return 1;
	212	}
47ca6ec2	213	EXPORT_SYMBOL(cfs_gettok);
d7e09d03 PT	214
	215	/**
	216	* Converts string to integer.
	217	*
	218	* Accepts decimal and hexadecimal number recordings.
	219	*
	220	* \retval 1 if first \a nob chars of \a str convert to decimal or
	221	* hexadecimal integer in the range [\a min, \a max]
	222	* \retval 0 otherwise
	223	*/
	224	int
	225	cfs_str2num_check(char str, int nob, unsigned num,
	226	unsigned min, unsigned max)
	227	{
3ad6152d JS	228	bool all_numbers = true;
3ad6152d JS	229	char *endp, cache;
ae0246da	230	int rc;
d7e09d03	231
3ad6152d JS	232	/**
	233	* kstrouint can only handle strings composed
	234	* of only numbers. We need to scan the string
	235	* passed in for the first non-digit character
	236	* and end the string at that location. If we
	237	* don't find any non-digit character we still
	238	* need to place a '\0' at position nob since
	239	* we are not interested in the rest of the
	240	* string which is longer than nob in size.
	241	* After we are done the character at the
	242	* position we placed '\0' must be restored.
	243	*/
	244	for (endp = str; endp < str + nob; endp++) {
	245	if (!isdigit(*endp)) {
	246	all_numbers = false;
	247	break;
	248	}
	249	}
	250	cache = *endp;
	251	*endp = '\0';
	252
ae0246da	253	rc = kstrtouint(str, 10, num);
3ad6152d JS	254	*endp = cache;
3ad6152d JS	255	if (rc \|\| !all_numbers)
d7e09d03 PT	256	return 0;
d7e09d03 PT	257
d7e09d03 PT	258	return (num >= min && num <= max);
d7e09d03 PT	259	}
47ca6ec2	260	EXPORT_SYMBOL(cfs_str2num_check);
d7e09d03 PT	261
	262	/**
	263	* Parses \<range_expr\> token of the syntax. If \a bracketed is false,
	264	* \a src should only have a single token which can be \<number\> or \*
	265	*
	266	* \retval pointer to allocated range_expr and initialized
	267	* range_expr::re_lo, range_expr::re_hi and range_expr:re_stride if \a
	268	`* src parses to
	269	* \<number\> \|
	270	* \<number\> '-' \<number\> \|
	271	* \<number\> '-' \<number\> '/' \<number\>
	272	* \retval 0 will be returned if it can be parsed, otherwise -EINVAL or
	273	* -ENOMEM will be returned.
	274	*/
31fb613a	275	static int
d7e09d03 PT	276	cfs_range_expr_parse(struct cfs_lstr *src, unsigned min, unsigned max,
	277	int bracketed, struct cfs_range_expr **expr)
	278	{
	279	struct cfs_range_expr *re;
	280	struct cfs_lstr tok;
	281
	282	LIBCFS_ALLOC(re, sizeof(*re));
15d9f520	283	if (!re)
d7e09d03 PT	284	return -ENOMEM;
	285
	286	if (src->ls_len == 1 && src->ls_str[0] == '*') {
	287	re->re_lo = min;
	288	re->re_hi = max;
	289	re->re_stride = 1;
	290	goto out;
	291	}
	292
	293	if (cfs_str2num_check(src->ls_str, src->ls_len,
	294	&re->re_lo, min, max)) {
	295	/* <number> is parsed */
	296	re->re_hi = re->re_lo;
	297	re->re_stride = 1;
	298	goto out;
	299	}
	300
	301	if (!bracketed \|\| !cfs_gettok(src, '-', &tok))
	302	goto failed;
	303
	304	if (!cfs_str2num_check(tok.ls_str, tok.ls_len,
	305	&re->re_lo, min, max))
	306	goto failed;
	307
	308	/* <number> - */
	309	if (cfs_str2num_check(src->ls_str, src->ls_len,
	310	&re->re_hi, min, max)) {
	311	/* <number> - <number> is parsed */
	312	re->re_stride = 1;
	313	goto out;
	314	}
	315
	316	/* go to check <number> '-' <number> '/' <number> */
	317	if (cfs_gettok(src, '/', &tok)) {
	318	if (!cfs_str2num_check(tok.ls_str, tok.ls_len,
	319	&re->re_hi, min, max))
	320	goto failed;
	321
	322	/* <number> - <number> / ... */
	323	if (cfs_str2num_check(src->ls_str, src->ls_len,
	324	&re->re_stride, min, max)) {
	325	/* <number> - <number> / <number> is parsed */
	326	goto out;
	327	}
	328	}
	329
	330	out:
	331	*expr = re;
	332	return 0;
	333
	334	failed:
	335	LIBCFS_FREE(re, sizeof(*re));
	336	return -EINVAL;
	337	}
d7e09d03	338
a1dfc93a GP	339	/**
	340	* Print the range expression \a re into specified \a buffer.
	341	* If \a bracketed is true, expression does not need additional
	342	* brackets.
	343	*
	344	* \retval number of characters written
	345	*/
	346	static int
	347	cfs_range_expr_print(char buffer, int count, struct cfs_range_expr expr,
	348	bool bracketed)
	349	{
	350	int i;
	351	char s[] = "[";
	352	char e[] = "]";
	353
34ec7f89 OD	354	if (bracketed) {
	355	s[0] = '\0';
	356	e[0] = '\0';
	357	}
a1dfc93a GP	358
	359	if (expr->re_lo == expr->re_hi)
	360	i = scnprintf(buffer, count, "%u", expr->re_lo);
	361	else if (expr->re_stride == 1)
	362	i = scnprintf(buffer, count, "%s%u-%u%s",
ae0b4833	363	s, expr->re_lo, expr->re_hi, e);
a1dfc93a GP	364	else
a1dfc93a GP	365	i = scnprintf(buffer, count, "%s%u-%u/%u%s",
ae0b4833	366	s, expr->re_lo, expr->re_hi, expr->re_stride, e);
a1dfc93a GP	367	return i;
	368	}
	369
	370	/**
	371	* Print a list of range expressions (\a expr_list) into specified \a buffer.
	372	* If the list contains several expressions, separate them with comma
	373	* and surround the list with brackets.
	374	*
	375	* \retval number of characters written
	376	*/
	377	int
	378	cfs_expr_list_print(char buffer, int count, struct cfs_expr_list expr_list)
	379	{
	380	struct cfs_range_expr *expr;
	381	int i = 0, j = 0;
	382	int numexprs = 0;
	383
	384	if (count <= 0)
	385	return 0;
	386
	387	list_for_each_entry(expr, &expr_list->el_exprs, re_link)
	388	numexprs++;
	389
	390	if (numexprs > 1)
	391	i += scnprintf(buffer + i, count - i, "[");
	392
	393	list_for_each_entry(expr, &expr_list->el_exprs, re_link) {
	394	if (j++ != 0)
	395	i += scnprintf(buffer + i, count - i, ",");
	396	i += cfs_range_expr_print(buffer + i, count - i, expr,
	397	numexprs > 1);
	398	}
	399
	400	if (numexprs > 1)
	401	i += scnprintf(buffer + i, count - i, "]");
	402
	403	return i;
	404	}
	405	EXPORT_SYMBOL(cfs_expr_list_print);
	406
d7e09d03 PT	407	/**
	408	* Matches value (\a value) against ranges expression list \a expr_list.
	409	*
	410	* \retval 1 if \a value matches
	411	* \retval 0 otherwise
	412	*/
	413	int
	414	cfs_expr_list_match(__u32 value, struct cfs_expr_list *expr_list)
	415	{
	416	struct cfs_range_expr *expr;
	417
	418	list_for_each_entry(expr, &expr_list->el_exprs, re_link) {
	419	if (value >= expr->re_lo && value <= expr->re_hi &&
	420	((value - expr->re_lo) % expr->re_stride) == 0)
	421	return 1;
	422	}
	423
	424	return 0;
	425	}
47ca6ec2	426	EXPORT_SYMBOL(cfs_expr_list_match);
d7e09d03 PT	427
	428	/**
	429	* Convert express list (\a expr_list) to an array of all matched values
	430	*
	431	* \retval N N is total number of all matched values
	432	* \retval 0 if expression list is empty
	433	* \retval < 0 for failure
	434	*/
	435	int
	436	cfs_expr_list_values(struct cfs_expr_list expr_list, int max, __u32 *valpp)
	437	{
	438	struct cfs_range_expr *expr;
	439	__u32 *val;
	440	int count = 0;
	441	int i;
	442
	443	list_for_each_entry(expr, &expr_list->el_exprs, re_link) {
	444	for (i = expr->re_lo; i <= expr->re_hi; i++) {
	445	if (((i - expr->re_lo) % expr->re_stride) == 0)
	446	count++;
	447	}
	448	}
	449
	450	if (count == 0) /* empty expression list */
	451	return 0;
	452
	453	if (count > max) {
	454	CERROR("Number of values %d exceeds max allowed %d\n",
	455	max, count);
	456	return -EINVAL;
	457	}
	458
	459	LIBCFS_ALLOC(val, sizeof(val[0]) * count);
15d9f520	460	if (!val)
d7e09d03 PT	461	return -ENOMEM;
	462
	463	count = 0;
	464	list_for_each_entry(expr, &expr_list->el_exprs, re_link) {
	465	for (i = expr->re_lo; i <= expr->re_hi; i++) {
	466	if (((i - expr->re_lo) % expr->re_stride) == 0)
	467	val[count++] = i;
	468	}
	469	}
	470
	471	*valpp = val;
	472	return count;
	473	}
	474	EXPORT_SYMBOL(cfs_expr_list_values);
	475
	476	/**
	477	* Frees cfs_range_expr structures of \a expr_list.
	478	*
	479	* \retval none
	480	*/
	481	void
	482	cfs_expr_list_free(struct cfs_expr_list *expr_list)
	483	{
	484	while (!list_empty(&expr_list->el_exprs)) {
	485	struct cfs_range_expr *expr;
	486
	487	expr = list_entry(expr_list->el_exprs.next,
ae0b4833	488	struct cfs_range_expr, re_link);
d7e09d03 PT	489	list_del(&expr->re_link);
	490	LIBCFS_FREE(expr, sizeof(*expr));
	491	}
	492
	493	LIBCFS_FREE(expr_list, sizeof(*expr_list));
	494	}
	495	EXPORT_SYMBOL(cfs_expr_list_free);
	496
d7e09d03 PT	497	/**
	498	* Parses \<cfs_expr_list\> token of the syntax.
	499	*
a1dfc93a GP	500	* \retval 0 if \a str parses to \<number\> \| \<expr_list\>
a1dfc93a GP	501	* \retval -errno otherwise
d7e09d03 PT	502	*/
	503	int
	504	cfs_expr_list_parse(char *str, int len, unsigned min, unsigned max,
	505	struct cfs_expr_list **elpp)
	506	{
	507	struct cfs_expr_list *expr_list;
	508	struct cfs_range_expr *expr;
	509	struct cfs_lstr src;
	510	int rc;
	511
	512	LIBCFS_ALLOC(expr_list, sizeof(*expr_list));
15d9f520	513	if (!expr_list)
d7e09d03 PT	514	return -ENOMEM;
	515
	516	src.ls_str = str;
	517	src.ls_len = len;
	518
	519	INIT_LIST_HEAD(&expr_list->el_exprs);
	520
	521	if (src.ls_str[0] == '[' &&
	522	src.ls_str[src.ls_len - 1] == ']') {
	523	src.ls_str++;
	524	src.ls_len -= 2;
	525
	526	rc = -EINVAL;
15d9f520	527	while (src.ls_str) {
d7e09d03 PT	528	struct cfs_lstr tok;
	529
	530	if (!cfs_gettok(&src, ',', &tok)) {
	531	rc = -EINVAL;
	532	break;
	533	}
	534
	535	rc = cfs_range_expr_parse(&tok, min, max, 1, &expr);
	536	if (rc != 0)
	537	break;
	538
ae0b4833	539	list_add_tail(&expr->re_link, &expr_list->el_exprs);
d7e09d03 PT	540	}
	541	} else {
	542	rc = cfs_range_expr_parse(&src, min, max, 0, &expr);
ae0b4833 OD	543	if (rc == 0)
ae0b4833 OD	544	list_add_tail(&expr->re_link, &expr_list->el_exprs);
d7e09d03 PT	545	}
	546
	547	if (rc != 0)
	548	cfs_expr_list_free(expr_list);
	549	else
	550	*elpp = expr_list;
	551
	552	return rc;
	553	}
	554	EXPORT_SYMBOL(cfs_expr_list_parse);
	555
	556	/**
	557	* Frees cfs_expr_list structures of \a list.
	558	*
	559	* For each struct cfs_expr_list structure found on \a list it frees
	560	* range_expr list attached to it and frees the cfs_expr_list itself.
	561	*
	562	* \retval none
	563	*/
	564	void
	565	cfs_expr_list_free_list(struct list_head *list)
	566	{
	567	struct cfs_expr_list *el;
	568
	569	while (!list_empty(list)) {
ae0b4833	570	el = list_entry(list->next, struct cfs_expr_list, el_link);
d7e09d03 PT	571	list_del(&el->el_link);
	572	cfs_expr_list_free(el);
	573	}
	574	}
47ca6ec2	575	EXPORT_SYMBOL(cfs_expr_list_free_list);