[thirdparty/u-boot.git] / cmd / setexpr.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * Copyright 2008 Freescale Semiconductor, Inc.
 * Copyright 2013 Wolfgang Denk <wd@denx.de>
 */

/*
 * This file provides a shell like 'expr' function to return.
 */

#include <common.h>
#include <config.h>
#include <command.h>
#include <mapmem.h>

static ulong get_arg(char *s, int w)
{
	/*
	 * If the parameter starts with a '*' then assume it is a pointer to
	 * the value we want.
	 */
	if (s[0] == '*') {
		ulong *p;
		ulong addr;
		ulong val;

		addr = simple_strtoul(&s[1], NULL, 16);
		switch (w) {
		case 1:
			p = map_sysmem(addr, sizeof(uchar));
			val = (ulong)*(uchar *)p;
			unmap_sysmem(p);
			return val;
		case 2:
			p = map_sysmem(addr, sizeof(ushort));
			val = (ulong)*(ushort *)p;
			unmap_sysmem(p);
			return val;
		case 4:
		default:
			p = map_sysmem(addr, sizeof(ulong));
			val = *p;
			unmap_sysmem(p);
			return val;
		}
	} else {
		return simple_strtoul(s, NULL, 16);
	}
}

#ifdef CONFIG_REGEX

#include <slre.h>

#define SLRE_BUFSZ	16384
#define SLRE_PATSZ	4096

/*
 * memstr - Find the first substring in memory
 * @s1: The string to be searched
 * @s2: The string to search for
 *
 * Similar to and based on strstr(),
 * but strings do not need to be NUL terminated.
 */
static char *memstr(const char *s1, int l1, const char *s2, int l2)
{
	if (!l2)
		return (char *)s1;

	while (l1 >= l2) {
		l1--;
		if (!memcmp(s1, s2, l2))
			return (char *)s1;
		s1++;
	}
	return NULL;
}

static char *substitute(char *string,	/* string buffer */
			int *slen,	/* current string length */
			int ssize,	/* string bufer size */
			const char *old,/* old (replaced) string */
			int olen,	/* length of old string */
			const char *new,/* new (replacement) string */
			int nlen)	/* length of new string */
{
	char *p = memstr(string, *slen, old, olen);

	if (p == NULL)
		return NULL;

	debug("## Match at pos %ld: match len %d, subst len %d\n",
		(long)(p - string), olen, nlen);

	/* make sure replacement matches */
	if (*slen + nlen - olen > ssize) {
		printf("## error: substitution buffer overflow\n");
		return NULL;
	}

	/* move tail if needed */
	if (olen != nlen) {
		int tail, len;

		len = (olen > nlen) ? olen : nlen;

		tail = ssize - (p + len - string);

		debug("## tail len %d\n", tail);

		memmove(p + nlen, p + olen, tail);
	}

	/* insert substitue */
	memcpy(p, new, nlen);

	*slen += nlen - olen;

	return p + nlen;
}

/*
 * Perform regex operations on a environment variable
 *
 * Returns 0 if OK, 1 in case of errors.
 */
static int regex_sub(const char *name,
	const char *r, const char *s, const char *t,
	int global)
{
	struct slre slre;
	char data[SLRE_BUFSZ];
	char *datap = data;
	const char *value;
	int res, len, nlen, loop;

	if (name == NULL)
		return 1;

	if (slre_compile(&slre, r) == 0) {
		printf("Error compiling regex: %s\n", slre.err_str);
		return 1;
	}

	if (t == NULL) {
		value = env_get(name);

		if (value == NULL) {
			printf("## Error: variable \"%s\" not defined\n", name);
			return 1;
		}
		t = value;
	}

	debug("REGEX on %s=%s\n", name, t);
	debug("REGEX=\"%s\", SUBST=\"%s\", GLOBAL=%d\n",
		r, s ? s : "<NULL>", global);

	len = strlen(t);
	if (len + 1 > SLRE_BUFSZ) {
		printf("## error: subst buffer overflow: have %d, need %d\n",
			SLRE_BUFSZ, len + 1);
		return 1;
	}

	strcpy(data, t);

	if (s == NULL)
		nlen = 0;
	else
		nlen = strlen(s);

	for (loop = 0;; loop++) {
		struct cap caps[slre.num_caps + 2];
		char nbuf[SLRE_PATSZ];
		const char *old;
		char *np;
		int i, olen;

		(void) memset(caps, 0, sizeof(caps));

		res = slre_match(&slre, datap, len, caps);

		debug("Result: %d\n", res);

		for (i = 0; i < slre.num_caps; i++) {
			if (caps[i].len > 0) {
				debug("Substring %d: [%.*s]\n", i,
					caps[i].len, caps[i].ptr);
			}
		}

		if (res == 0) {
			if (loop == 0) {
				printf("%s: No match\n", t);
				return 1;
			} else {
				break;
			}
		}

		debug("## MATCH ## %s\n", data);

		if (s == NULL) {
			printf("%s=%s\n", name, t);
			return 1;
		}

		old = caps[0].ptr;
		olen = caps[0].len;

		if (nlen + 1 >= SLRE_PATSZ) {
			printf("## error: pattern buffer overflow: have %d, need %d\n",
				SLRE_BUFSZ, nlen + 1);
			return 1;
		}
		strcpy(nbuf, s);

		debug("## SUBST(1) ## %s\n", nbuf);

		/*
		 * Handle back references
		 *
		 * Support for \0 ... \9, where \0 is the
		 * whole matched pattern (similar to &).
		 *
		 * Implementation is a bit simpleminded as
		 * backrefs are substituted sequentially, one
		 * by one.  This will lead to somewhat
		 * unexpected results if the replacement
		 * strings contain any \N strings then then
		 * may get substitued, too.  We accept this
		 * restriction for the sake of simplicity.
		 */
		for (i = 0; i < 10; ++i) {
			char backref[2] = {
				'\\',
				'0',
			};

			if (caps[i].len == 0)
				break;

			backref[1] += i;

			debug("## BACKREF %d: replace \"%.*s\" by \"%.*s\" in \"%s\"\n",
				i,
				2, backref,
				caps[i].len, caps[i].ptr,
				nbuf);

			for (np = nbuf;;) {
				char *p = memstr(np, nlen, backref, 2);

				if (p == NULL)
					break;

				np = substitute(np, &nlen,
					SLRE_PATSZ,
					backref, 2,
					caps[i].ptr, caps[i].len);

				if (np == NULL)
					return 1;
			}
		}
		debug("## SUBST(2) ## %s\n", nbuf);

		datap = substitute(datap, &len, SLRE_BUFSZ,
				old, olen,
				nbuf, nlen);

		if (datap == NULL)
			return 1;

		debug("## REMAINDER: %s\n", datap);

		debug("## RESULT: %s\n", data);

		if (!global)
			break;
	}
	debug("## FINAL (now env_set()) :  %s\n", data);

	printf("%s=%s\n", name, data);

	return env_set(name, data);
}
#endif

static int do_setexpr(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
	ulong a, b;
	ulong value;
	int w;

	/*
	 * We take 3, 5, or 6 arguments:
	 * 3 : setexpr name value
	 * 5 : setexpr name val1 op val2
	 *     setexpr name [g]sub r s
	 * 6 : setexpr name [g]sub r s t
	 */

	/* > 6 already tested by max command args */
	if ((argc < 3) || (argc == 4))
		return CMD_RET_USAGE;

	w = cmd_get_data_size(argv[0], 4);

	a = get_arg(argv[2], w);

	/* plain assignment: "setexpr name value" */
	if (argc == 3) {
		env_set_hex(argv[1], a);
		return 0;
	}

	/* 5 or 6 args (6 args only with [g]sub) */
#ifdef CONFIG_REGEX
	/*
	 * rexep handling: "setexpr name [g]sub r s [t]"
	 * with 5 args, "t" will be NULL
	 */
	if (strcmp(argv[2], "gsub") == 0)
		return regex_sub(argv[1], argv[3], argv[4], argv[5], 1);

	if (strcmp(argv[2], "sub") == 0)
		return regex_sub(argv[1], argv[3], argv[4], argv[5], 0);
#endif

	/* standard operators: "setexpr name val1 op val2" */
	if (argc != 5)
		return CMD_RET_USAGE;

	if (strlen(argv[3]) != 1)
		return CMD_RET_USAGE;

	b = get_arg(argv[4], w);

	switch (argv[3][0]) {
	case '|':
		value = a | b;
		break;
	case '&':
		value = a & b;
		break;
	case '+':
		value = a + b;
		break;
	case '^':
		value = a ^ b;
		break;
	case '-':
		value = a - b;
		break;
	case '*':
		value = a * b;
		break;
	case '/':
		value = a / b;
		break;
	case '%':
		value = a % b;
		break;
	default:
		printf("invalid op\n");
		return 1;
	}

	env_set_hex(argv[1], value);

	return 0;
}

U_BOOT_CMD(
	setexpr, 6, 0, do_setexpr,
	"set environment variable as the result of eval expression",
	"[.b, .w, .l] name [*]value1 <op> [*]value2\n"
	"    - set environment variable 'name' to the result of the evaluated\n"
	"      expression specified by <op>.  <op> can be &, |, ^, +, -, *, /, %\n"
	"      size argument is only meaningful if value1 and/or value2 are\n"
	"      memory addresses (*)\n"
	"setexpr[.b, .w, .l] name [*]value\n"
	"    - load a value into a variable"
#ifdef CONFIG_REGEX
	"\n"
	"setexpr name gsub r s [t]\n"
	"    - For each substring matching the regular expression <r> in the\n"
	"      string <t>, substitute the string <s>.  The result is\n"
	"      assigned to <name>.  If <t> is not supplied, use the old\n"
	"      value of <name>\n"
	"setexpr name sub r s [t]\n"
	"    - Just like gsub(), but replace only the first matching substring"
#endif
);
Commit	Line	Data
83d290c5	1	// SPDX-License-Identifier: GPL-2.0+
d058698f KG	2	/*
d058698f KG	3	* Copyright 2008 Freescale Semiconductor, Inc.
855f18ea	4	* Copyright 2013 Wolfgang Denk <wd@denx.de>
d058698f KG	5	*/
	6
	7	/*
	8	* This file provides a shell like 'expr' function to return.
	9	*/
	10
	11	#include <common.h>
	12	#include <config.h>
	13	#include <command.h>
2068cea1	14	#include <mapmem.h>
d058698f	15
47ab5ad1 FM	16	static ulong get_arg(char *s, int w)
47ab5ad1 FM	17	{
482126e2	18	/*
2068cea1 JH	19	* If the parameter starts with a '*' then assume it is a pointer to
2068cea1 JH	20	* the value we want.
47ab5ad1	21	*/
47ab5ad1	22	if (s[0] == '*') {
2068cea1 JH	23	ulong *p;
	24	ulong addr;
	25	ulong val;
	26
	27	addr = simple_strtoul(&s[1], NULL, 16);
47ab5ad1	28	switch (w) {
2068cea1 JH	29	case 1:
	30	p = map_sysmem(addr, sizeof(uchar));
	31	val = (ulong)(uchar )p;
	32	unmap_sysmem(p);
	33	return val;
	34	case 2:
	35	p = map_sysmem(addr, sizeof(ushort));
	36	val = (ulong)(ushort )p;
	37	unmap_sysmem(p);
	38	return val;
47ab5ad1	39	case 4:
2068cea1 JH	40	default:
	41	p = map_sysmem(addr, sizeof(ulong));
	42	val = *p;
	43	unmap_sysmem(p);
	44	return val;
47ab5ad1 FM	45	}
	46	} else {
	47	return simple_strtoul(s, NULL, 16);
	48	}
	49	}
	50
855f18ea WD	51	#ifdef CONFIG_REGEX
	52
	53	#include <slre.h>
	54
	55	#define SLRE_BUFSZ 16384
	56	#define SLRE_PATSZ 4096
	57
	58	/*
	59	* memstr - Find the first substring in memory
	60	* @s1: The string to be searched
	61	* @s2: The string to search for
	62	*
	63	* Similar to and based on strstr(),
	64	* but strings do not need to be NUL terminated.
	65	*/
	66	static char memstr(const char s1, int l1, const char *s2, int l2)
	67	{
	68	if (!l2)
	69	return (char *)s1;
	70
	71	while (l1 >= l2) {
	72	l1--;
	73	if (!memcmp(s1, s2, l2))
	74	return (char *)s1;
	75	s1++;
	76	}
	77	return NULL;
	78	}
	79
	80	static char substitute(char string, /* string buffer */
	81	int slen, / current string length */
	82	int ssize, /* string bufer size */
	83	const char old,/ old (replaced) string */
	84	int olen, /* length of old string */
	85	const char new,/ new (replacement) string */
	86	int nlen) /* length of new string */
	87	{
	88	char p = memstr(string, slen, old, olen);
	89
	90	if (p == NULL)
	91	return NULL;
	92
	93	debug("## Match at pos %ld: match len %d, subst len %d\n",
	94	(long)(p - string), olen, nlen);
	95
	96	/* make sure replacement matches */
	97	if (*slen + nlen - olen > ssize) {
	98	printf("## error: substitution buffer overflow\n");
	99	return NULL;
	100	}
	101
	102	/* move tail if needed */
	103	if (olen != nlen) {
	104	int tail, len;
	105
	106	len = (olen > nlen) ? olen : nlen;
	107
	108	tail = ssize - (p + len - string);
	109
	110	debug("## tail len %d\n", tail);
	111
	112	memmove(p + nlen, p + olen, tail);
	113	}
	114
115	/* insert substitue */
116	memcpy(p, new, nlen);
117
118	*slen += nlen - olen;
119
120	return p + nlen;
121	}
122
123	/*
124	* Perform regex operations on a environment variable
125	*
126	* Returns 0 if OK, 1 in case of errors.
127	*/
128	static int regex_sub(const char *name,
129	const char r, const char s, const char *t,
130	int global)
131	{
132	struct slre slre;
133	char data[SLRE_BUFSZ];
134	char *datap = data;
135	const char *value;
136	int res, len, nlen, loop;
137
138	if (name == NULL)
139	return 1;
140
141	if (slre_compile(&slre, r) == 0) {
142	printf("Error compiling regex: %s\n", slre.err_str);
143	return 1;
144	}
145
146	if (t == NULL) {
00caae6d	147	value = env_get(name);
855f18ea WD	148
	149	if (value == NULL) {
	150	printf("## Error: variable \"%s\" not defined\n", name);
	151	return 1;
	152	}
	153	t = value;
	154	}
	155
	156	debug("REGEX on %s=%s\n", name, t);
	157	debug("REGEX=\"%s\", SUBST=\"%s\", GLOBAL=%d\n",
	158	r, s ? s : "<NULL>", global);
	159
	160	len = strlen(t);
	161	if (len + 1 > SLRE_BUFSZ) {
	162	printf("## error: subst buffer overflow: have %d, need %d\n",
	163	SLRE_BUFSZ, len + 1);
	164	return 1;
	165	}
	166
	167	strcpy(data, t);
	168
	169	if (s == NULL)
	170	nlen = 0;
	171	else
	172	nlen = strlen(s);
	173
	174	for (loop = 0;; loop++) {
	175	struct cap caps[slre.num_caps + 2];
	176	char nbuf[SLRE_PATSZ];
	177	const char *old;
	178	char *np;
	179	int i, olen;
	180
	181	(void) memset(caps, 0, sizeof(caps));
	182
	183	res = slre_match(&slre, datap, len, caps);
	184
	185	debug("Result: %d\n", res);
	186
	187	for (i = 0; i < slre.num_caps; i++) {
	188	if (caps[i].len > 0) {
	189	debug("Substring %d: [%.*s]\n", i,
	190	caps[i].len, caps[i].ptr);
	191	}
	192	}
	193
	194	if (res == 0) {
	195	if (loop == 0) {
	196	printf("%s: No match\n", t);
	197	return 1;
	198	} else {
	199	break;
	200	}
	201	}
	202
	203	debug("## MATCH ## %s\n", data);
	204
	205	if (s == NULL) {
	206	printf("%s=%s\n", name, t);
	207	return 1;
	208	}
	209
	210	old = caps[0].ptr;
	211	olen = caps[0].len;
212
213	if (nlen + 1 >= SLRE_PATSZ) {
214	printf("## error: pattern buffer overflow: have %d, need %d\n",
215	SLRE_BUFSZ, nlen + 1);
216	return 1;
217	}
218	strcpy(nbuf, s);
219
220	debug("## SUBST(1) ## %s\n", nbuf);
221
222	/*
223	* Handle back references
224	*
225	* Support for \0 ... \9, where \0 is the
226	* whole matched pattern (similar to &).
227	*
228	* Implementation is a bit simpleminded as
229	* backrefs are substituted sequentially, one
230	* by one. This will lead to somewhat
231	* unexpected results if the replacement
232	* strings contain any \N strings then then
233	* may get substitued, too. We accept this
234	* restriction for the sake of simplicity.
235	*/
236	for (i = 0; i < 10; ++i) {
237	char backref[2] = {
238	'\\',
239	'0',
240	};
241
242	if (caps[i].len == 0)
243	break;
244
245	backref[1] += i;
246
247	debug("## BACKREF %d: replace \"%.s\" by \"%.s\" in \"%s\"\n",
248	i,
249	2, backref,
250	caps[i].len, caps[i].ptr,
251	nbuf);
252
253	for (np = nbuf;;) {
254	char *p = memstr(np, nlen, backref, 2);
255
256	if (p == NULL)
257	break;
258
259	np = substitute(np, &nlen,
260	SLRE_PATSZ,
261	backref, 2,
262	caps[i].ptr, caps[i].len);
263
264	if (np == NULL)
265	return 1;
266	}
267	}
268	debug("## SUBST(2) ## %s\n", nbuf);
269
270	datap = substitute(datap, &len, SLRE_BUFSZ,
271	old, olen,
272	nbuf, nlen);
273
274	if (datap == NULL)
275	return 1;
276
277	debug("## REMAINDER: %s\n", datap);
278
279	debug("## RESULT: %s\n", data);
280
281	if (!global)
282	break;
283	}
382bee57	284	debug("## FINAL (now env_set()) : %s\n", data);
855f18ea WD	285
	286	printf("%s=%s\n", name, data);
	287
382bee57	288	return env_set(name, data);
855f18ea WD	289	}
	290	#endif
	291
088f1b19	292	static int do_setexpr(cmd_tbl_t cmdtp, int flag, int argc, char const argv[])
d058698f KG	293	{
d058698f KG	294	ulong a, b;
41ef372c	295	ulong value;
47ab5ad1	296	int w;
d058698f	297
855f18ea WD	298	/*
	299	* We take 3, 5, or 6 arguments:
	300	* 3 : setexpr name value
	301	* 5 : setexpr name val1 op val2
	302	* setexpr name [g]sub r s
	303	* 6 : setexpr name [g]sub r s t
	304	*/
	305
	306	/* > 6 already tested by max command args */
	307	if ((argc < 3) \|\| (argc == 4))
4c12eeb8	308	return CMD_RET_USAGE;
d058698f	309
47ab5ad1 FM	310	w = cmd_get_data_size(argv[0], 4);
	311
	312	a = get_arg(argv[2], w);
4823b45d	313
103c94b1	314	/* plain assignment: "setexpr name value" */
4823b45d	315	if (argc == 3) {
018f5303	316	env_set_hex(argv[1], a);
4823b45d JH	317	return 0;
	318	}
	319
855f18ea WD	320	/* 5 or 6 args (6 args only with [g]sub) */
	321	#ifdef CONFIG_REGEX
	322	/*
	323	* rexep handling: "setexpr name [g]sub r s [t]"
	324	* with 5 args, "t" will be NULL
	325	*/
	326	if (strcmp(argv[2], "gsub") == 0)
	327	return regex_sub(argv[1], argv[3], argv[4], argv[5], 1);
	328
	329	if (strcmp(argv[2], "sub") == 0)
	330	return regex_sub(argv[1], argv[3], argv[4], argv[5], 0);
	331	#endif
	332
103c94b1 WD	333	/* standard operators: "setexpr name val1 op val2" */
	334	if (argc != 5)
	335	return CMD_RET_USAGE;
	336
	337	if (strlen(argv[3]) != 1)
	338	return CMD_RET_USAGE;
	339
47ab5ad1	340	b = get_arg(argv[4], w);
d058698f KG	341
d058698f KG	342	switch (argv[3][0]) {
41ef372c SG	343	case '\|':
	344	value = a \| b;
	345	break;
	346	case '&':
	347	value = a & b;
	348	break;
	349	case '+':
	350	value = a + b;
	351	break;
	352	case '^':
	353	value = a ^ b;
	354	break;
	355	case '-':
	356	value = a - b;
	357	break;
	358	case '*':
	359	value = a * b;
	360	break;
	361	case '/':
	362	value = a / b;
	363	break;
	364	case '%':
	365	value = a % b;
	366	break;
d058698f KG	367	default:
	368	printf("invalid op\n");
	369	return 1;
	370	}
	371
018f5303	372	env_set_hex(argv[1], value);
d058698f KG	373
	374	return 0;
	375	}
	376
	377	U_BOOT_CMD(
855f18ea	378	setexpr, 6, 0, do_setexpr,
2fb2604d	379	"set environment variable as the result of eval expression",
4823b45d	380	"[.b, .w, .l] name []value1 <op> []value2\n"
d058698f	381	" - set environment variable 'name' to the result of the evaluated\n"
855f18ea	382	" expression specified by <op>. <op> can be &, \|, ^, +, -, *, /, %\n"
4823b45d JH	383	" size argument is only meaningful if value1 and/or value2 are\n"
4823b45d JH	384	" memory addresses (*)\n"
103c94b1 WD	385	"setexpr[.b, .w, .l] name [*]value\n"
103c94b1 WD	386	" - load a value into a variable"
855f18ea WD	387	#ifdef CONFIG_REGEX
	388	"\n"
	389	"setexpr name gsub r s [t]\n"
	390	" - For each substring matching the regular expression <r> in the\n"
	391	" string <t>, substitute the string <s>. The result is\n"
	392	" assigned to <name>. If <t> is not supplied, use the old\n"
	393	" value of <name>\n"
	394	"setexpr name sub r s [t]\n"
	395	" - Just like gsub(), but replace only the first matching substring"
	396	#endif
d058698f	397	);