[people/ms/u-boot.git] / common / env_attr.c

/*
 * (C) Copyright 2012
 * Joe Hershberger, National Instruments, joe.hershberger@ni.com
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#ifdef USE_HOSTCC /* Eliminate "ANSI does not permit..." warnings */
#include <stdint.h>
#include <stdio.h>
#include <linux/linux_string.h>
#else
#include <common.h>
#include <slre.h>
#endif

#include <env_attr.h>
#include <errno.h>
#include <linux/string.h>
#include <malloc.h>

/*
 * Iterate through the whole list calling the callback for each found element.
 * "attr_list" takes the form:
 *	attributes = [^,:\s]*
 *	entry = name[:attributes]
 *	list = entry[,list]
 */
int env_attr_walk(const char *attr_list,
	int (*callback)(const char *name, const char *attributes, void *priv),
	void *priv)
{
	const char *entry, *entry_end;
	char *name, *attributes;

	if (!attr_list)
		/* list not found */
		return 1;

	entry = attr_list;
	do {
		char *entry_cpy = NULL;

		entry_end = strchr(entry, ENV_ATTR_LIST_DELIM);
		/* check if this is the last entry in the list */
		if (entry_end == NULL) {
			int entry_len = strlen(entry);

			if (entry_len) {
				/*
				 * allocate memory to copy the entry into since
				 * we will need to inject '\0' chars and squash
				 * white-space before calling the callback
				 */
				entry_cpy = malloc(entry_len + 1);
				if (entry_cpy)
					/* copy the rest of the list */
					strcpy(entry_cpy, entry);
				else
					return -ENOMEM;
			}
		} else {
			int entry_len = entry_end - entry;

			if (entry_len) {
				/*
				 * allocate memory to copy the entry into since
				 * we will need to inject '\0' chars and squash
				 * white-space before calling the callback
				 */
				entry_cpy = malloc(entry_len + 1);
				if (entry_cpy) {
					/* copy just this entry and null term */
					strncpy(entry_cpy, entry, entry_len);
					entry_cpy[entry_len] = '\0';
				} else
					return -ENOMEM;
			}
		}

		/* check if there is anything to process (e.g. not ",,,") */
		if (entry_cpy != NULL) {
			attributes = strchr(entry_cpy, ENV_ATTR_SEP);
			/* check if there is a ':' */
			if (attributes != NULL) {
				/* replace the ':' with '\0' to term name */
				*attributes++ = '\0';
				/* remove white-space from attributes */
				attributes = strim(attributes);
			}
			/* remove white-space from name */
			name = strim(entry_cpy);

			/* only call the callback if there is a name */
			if (strlen(name) != 0) {
				int retval = 0;

				retval = callback(name, attributes, priv);
				if (retval) {
					free(entry_cpy);
					return retval;
				}
			}
		}

		free(entry_cpy);
		entry = entry_end + 1;
	} while (entry_end != NULL);

	return 0;
}

#if defined(CONFIG_REGEX)
struct regex_callback_priv {
	const char *searched_for;
	char *regex;
	char *attributes;
};

static int regex_callback(const char *name, const char *attributes, void *priv)
{
	int retval = 0;
	struct regex_callback_priv *cbp = (struct regex_callback_priv *)priv;
	struct slre slre;
	char regex[strlen(name) + 3];

	/* Require the whole string to be described by the regex */
	sprintf(regex, "^%s$", name);
	if (slre_compile(&slre, regex)) {
		struct cap caps[slre.num_caps + 2];

		if (slre_match(&slre, cbp->searched_for,
			       strlen(cbp->searched_for), caps)) {
			free(cbp->regex);
			cbp->regex = malloc(strlen(regex) + 1);
			if (cbp->regex) {
				strcpy(cbp->regex, regex);
			} else {
				retval = -ENOMEM;
				goto done;
			}

			free(cbp->attributes);
			cbp->attributes = malloc(strlen(attributes) + 1);
			if (cbp->attributes) {
				strcpy(cbp->attributes, attributes);
			} else {
				retval = -ENOMEM;
				free(cbp->regex);
				cbp->regex = NULL;
				goto done;
			}
		}
	} else {
		printf("Error compiling regex: %s\n", slre.err_str);
		retval = EINVAL;
	}
done:
	return retval;
}

/*
 * Retrieve the attributes string associated with a single name in the list
 * There is no protection on attributes being too small for the value
 */
int env_attr_lookup(const char *attr_list, const char *name, char *attributes)
{
	if (!attributes)
		/* bad parameter */
		return -EINVAL;
	if (!attr_list)
		/* list not found */
		return -EINVAL;

	struct regex_callback_priv priv;
	int retval;

	priv.searched_for = name;
	priv.regex = NULL;
	priv.attributes = NULL;
	retval = env_attr_walk(attr_list, regex_callback, &priv);
	if (retval)
		return retval; /* error */

	if (priv.regex) {
		strcpy(attributes, priv.attributes);
		free(priv.attributes);
		free(priv.regex);
		/* success */
		return 0;
	}
	return -ENOENT; /* not found in list */
}
#else

/*
 * Search for the last exactly matching name in an attribute list
 */
static int reverse_name_search(const char *searched, const char *search_for,
	const char **result)
{
	int result_size = 0;
	const char *cur_searched = searched;

	if (result)
		*result = NULL;

	if (*search_for == '\0') {
		if (result)
			*result = searched;
		return strlen(searched);
	}

	for (;;) {
		const char *match = strstr(cur_searched, search_for);
		const char *prevch;
		const char *nextch;

		/* Stop looking if no new match is found */
		if (match == NULL)
			break;

		prevch = match - 1;
		nextch = match + strlen(search_for);

		/* Skip spaces */
		while (*prevch == ' ' && prevch >= searched)
			prevch--;
		while (*nextch == ' ')
			nextch++;

		/* Start looking past the current match so last is found */
		cur_searched = match + 1;
		/* Check for an exact match */
		if (match != searched &&
		    *prevch != ENV_ATTR_LIST_DELIM &&
		    prevch != searched - 1)
			continue;
		if (*nextch != ENV_ATTR_SEP &&
		    *nextch != ENV_ATTR_LIST_DELIM &&
		    *nextch != '\0')
			continue;

		if (result)
			*result = match;
		result_size = strlen(search_for);
	}

	return result_size;
}

/*
 * Retrieve the attributes string associated with a single name in the list
 * There is no protection on attributes being too small for the value
 */
int env_attr_lookup(const char *attr_list, const char *name, char *attributes)
{
	const char *entry = NULL;
	int entry_len;

	if (!attributes)
		/* bad parameter */
		return -EINVAL;
	if (!attr_list)
		/* list not found */
		return -EINVAL;

	entry_len = reverse_name_search(attr_list, name, &entry);
	if (entry != NULL) {
		int len;

		/* skip the name */
		entry += entry_len;
		/* skip spaces */
		while (*entry == ' ')
			entry++;
		if (*entry != ENV_ATTR_SEP)
			len = 0;
		else {
			const char *delim;
			static const char delims[] = {
				ENV_ATTR_LIST_DELIM, ' ', '\0'};

			/* skip the attr sep */
			entry += 1;
			/* skip spaces */
			while (*entry == ' ')
				entry++;

			delim = strpbrk(entry, delims);
			if (delim == NULL)
				len = strlen(entry);
			else
				len = delim - entry;
			memcpy(attributes, entry, len);
		}
		attributes[len] = '\0';

		/* success */
		return 0;
	}

	/* not found in list */
	return -ENOENT;
}
#endif
Commit	Line	Data
170ab110 JH	1	/*
	2	* (C) Copyright 2012
	3	* Joe Hershberger, National Instruments, joe.hershberger@ni.com
	4	*
1a459660	5	* SPDX-License-Identifier: GPL-2.0+
170ab110 JH	6	*/
170ab110 JH	7
30fd4fad JH	8	#ifdef USE_HOSTCC /* Eliminate "ANSI does not permit..." warnings */
	9	#include <stdint.h>
	10	#include <stdio.h>
	11	#include <linux/linux_string.h>
	12	#else
170ab110	13	#include <common.h>
bdf1fe4e	14	#include <slre.h>
30fd4fad JH	15	#endif
30fd4fad JH	16
170ab110 JH	17	#include <env_attr.h>
	18	#include <errno.h>
	19	#include <linux/string.h>
	20	#include <malloc.h>
	21
	22	/*
	23	* Iterate through the whole list calling the callback for each found element.
	24	* "attr_list" takes the form:
	25	* attributes = [^,:\s]*
	26	* entry = name[:attributes]
	27	* list = entry[,list]
	28	*/
	29	int env_attr_walk(const char *attr_list,
cca98fd6 JH	30	int (callback)(const char name, const char attributes, void priv),
cca98fd6 JH	31	void *priv)
170ab110 JH	32	{
	33	const char entry, entry_end;
	34	char name, attributes;
	35
	36	if (!attr_list)
	37	/* list not found */
	38	return 1;
	39
	40	entry = attr_list;
	41	do {
	42	char *entry_cpy = NULL;
	43
	44	entry_end = strchr(entry, ENV_ATTR_LIST_DELIM);
	45	/* check if this is the last entry in the list */
	46	if (entry_end == NULL) {
	47	int entry_len = strlen(entry);
	48
	49	if (entry_len) {
	50	/*
	51	* allocate memory to copy the entry into since
	52	* we will need to inject '\0' chars and squash
	53	* white-space before calling the callback
	54	*/
	55	entry_cpy = malloc(entry_len + 1);
	56	if (entry_cpy)
	57	/* copy the rest of the list */
	58	strcpy(entry_cpy, entry);
	59	else
	60	return -ENOMEM;
	61	}
	62	} else {
	63	int entry_len = entry_end - entry;
	64
	65	if (entry_len) {
	66	/*
	67	* allocate memory to copy the entry into since
	68	* we will need to inject '\0' chars and squash
	69	* white-space before calling the callback
	70	*/
	71	entry_cpy = malloc(entry_len + 1);
	72	if (entry_cpy) {
	73	/* copy just this entry and null term */
	74	strncpy(entry_cpy, entry, entry_len);
	75	entry_cpy[entry_len] = '\0';
	76	} else
	77	return -ENOMEM;
	78	}
	79	}
	80
	81	/* check if there is anything to process (e.g. not ",,,") */
	82	if (entry_cpy != NULL) {
	83	attributes = strchr(entry_cpy, ENV_ATTR_SEP);
	84	/* check if there is a ':' */
	85	if (attributes != NULL) {
	86	/* replace the ':' with '\0' to term name */
	87	*attributes++ = '\0';
	88	/* remove white-space from attributes */
	89	attributes = strim(attributes);
	90	}
	91	/* remove white-space from name */
	92	name = strim(entry_cpy);
	93
	94	/* only call the callback if there is a name */
	95	if (strlen(name) != 0) {
96	int retval = 0;
97
cca98fd6	98	retval = callback(name, attributes, priv);
170ab110 JH	99	if (retval) {
	100	free(entry_cpy);
	101	return retval;
	102	}
	103	}
	104	}
	105
	106	free(entry_cpy);
	107	entry = entry_end + 1;
	108	} while (entry_end != NULL);
	109
	110	return 0;
	111	}
	112
bdf1fe4e JH	113	#if defined(CONFIG_REGEX)
	114	struct regex_callback_priv {
	115	const char *searched_for;
	116	char *regex;
	117	char *attributes;
	118	};
	119
	120	static int regex_callback(const char name, const char attributes, void *priv)
	121	{
	122	int retval = 0;
	123	struct regex_callback_priv cbp = (struct regex_callback_priv )priv;
	124	struct slre slre;
	125	char regex[strlen(name) + 3];
	126
	127	/* Require the whole string to be described by the regex */
	128	sprintf(regex, "^%s$", name);
	129	if (slre_compile(&slre, regex)) {
	130	struct cap caps[slre.num_caps + 2];
	131
	132	if (slre_match(&slre, cbp->searched_for,
	133	strlen(cbp->searched_for), caps)) {
	134	free(cbp->regex);
	135	cbp->regex = malloc(strlen(regex) + 1);
	136	if (cbp->regex) {
	137	strcpy(cbp->regex, regex);
	138	} else {
	139	retval = -ENOMEM;
	140	goto done;
	141	}
	142
	143	free(cbp->attributes);
	144	cbp->attributes = malloc(strlen(attributes) + 1);
	145	if (cbp->attributes) {
	146	strcpy(cbp->attributes, attributes);
	147	} else {
	148	retval = -ENOMEM;
	149	free(cbp->regex);
	150	cbp->regex = NULL;
	151	goto done;
	152	}
	153	}
	154	} else {
	155	printf("Error compiling regex: %s\n", slre.err_str);
	156	retval = EINVAL;
	157	}
	158	done:
	159	return retval;
	160	}
	161
	162	/*
	163	* Retrieve the attributes string associated with a single name in the list
	164	* There is no protection on attributes being too small for the value
	165	*/
	166	int env_attr_lookup(const char attr_list, const char name, char *attributes)
	167	{
	168	if (!attributes)
	169	/* bad parameter */
	170	return -EINVAL;
	171	if (!attr_list)
	172	/* list not found */
	173	return -EINVAL;
	174
	175	struct regex_callback_priv priv;
	176	int retval;
177
178	priv.searched_for = name;
179	priv.regex = NULL;
180	priv.attributes = NULL;
181	retval = env_attr_walk(attr_list, regex_callback, &priv);
182	if (retval)
183	return retval; /* error */
184
185	if (priv.regex) {
186	strcpy(attributes, priv.attributes);
187	free(priv.attributes);
188	free(priv.regex);
189	/* success */
190	return 0;
191	}
192	return -ENOENT; /* not found in list */
193	}
194	#else
195
170ab110	196	/*
032ea185	197	* Search for the last exactly matching name in an attribute list
170ab110	198	*/
032ea185 JH	199	static int reverse_name_search(const char searched, const char search_for,
032ea185 JH	200	const char **result)
170ab110	201	{
032ea185 JH	202	int result_size = 0;
032ea185 JH	203	const char *cur_searched = searched;
170ab110	204
032ea185 JH	205	if (result)
	206	*result = NULL;
	207
	208	if (*search_for == '\0') {
	209	if (result)
	210	*result = searched;
	211	return strlen(searched);
	212	}
170ab110 JH	213
170ab110 JH	214	for (;;) {
032ea185 JH	215	const char *match = strstr(cur_searched, search_for);
	216	const char *prevch;
	217	const char *nextch;
	218
	219	/* Stop looking if no new match is found */
	220	if (match == NULL)
170ab110 JH	221	break;
170ab110 JH	222
032ea185 JH	223	prevch = match - 1;
	224	nextch = match + strlen(search_for);
	225
	226	/* Skip spaces */
	227	while (*prevch == ' ' && prevch >= searched)
	228	prevch--;
	229	while (*nextch == ' ')
	230	nextch++;
	231
	232	/* Start looking past the current match so last is found */
	233	cur_searched = match + 1;
	234	/* Check for an exact match */
	235	if (match != searched &&
	236	*prevch != ENV_ATTR_LIST_DELIM &&
	237	prevch != searched - 1)
	238	continue;
	239	if (*nextch != ENV_ATTR_SEP &&
	240	*nextch != ENV_ATTR_LIST_DELIM &&
	241	*nextch != '\0')
	242	continue;
	243
	244	if (result)
	245	*result = match;
	246	result_size = strlen(search_for);
170ab110 JH	247	}
170ab110 JH	248
032ea185	249	return result_size;
170ab110 JH	250	}
	251
	252	/*
	253	* Retrieve the attributes string associated with a single name in the list
	254	* There is no protection on attributes being too small for the value
	255	*/
	256	int env_attr_lookup(const char attr_list, const char name, char *attributes)
	257	{
	258	const char *entry = NULL;
032ea185	259	int entry_len;
170ab110 JH	260
	261	if (!attributes)
	262	/* bad parameter */
7a0ad2cc	263	return -EINVAL;
170ab110 JH	264	if (!attr_list)
170ab110 JH	265	/* list not found */
7a0ad2cc	266	return -EINVAL;
170ab110	267
032ea185	268	entry_len = reverse_name_search(attr_list, name, &entry);
170ab110 JH	269	if (entry != NULL) {
	270	int len;
	271
	272	/* skip the name */
032ea185	273	entry += entry_len;
170ab110 JH	274	/* skip spaces */
	275	while (*entry == ' ')
	276	entry++;
	277	if (*entry != ENV_ATTR_SEP)
	278	len = 0;
	279	else {
	280	const char *delim;
	281	static const char delims[] = {
	282	ENV_ATTR_LIST_DELIM, ' ', '\0'};
	283
	284	/* skip the attr sep */
	285	entry += 1;
	286	/* skip spaces */
	287	while (*entry == ' ')
	288	entry++;
	289
	290	delim = strpbrk(entry, delims);
	291	if (delim == NULL)
	292	len = strlen(entry);
	293	else
	294	len = delim - entry;
	295	memcpy(attributes, entry, len);
	296	}
	297	attributes[len] = '\0';
	298
	299	/* success */
	300	return 0;
	301	}
	302
	303	/* not found in list */
7a0ad2cc	304	return -ENOENT;
170ab110	305	}
bdf1fe4e	306	#endif