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git.ipfire.org Git - thirdparty/u-boot.git/blob - cmd/setexpr.c
1 // SPDX-License-Identifier: GPL-2.0+
3 * Copyright 2008 Freescale Semiconductor, Inc.
4 * Copyright 2013 Wolfgang Denk <wd@denx.de>
8 * This file provides a shell like 'expr' function to return.
16 static ulong
get_arg(char *s
, int w
)
19 * If the parameter starts with a '*' then assume it is a pointer to
27 addr
= simple_strtoul(&s
[1], NULL
, 16);
30 p
= map_sysmem(addr
, sizeof(uchar
));
31 val
= (ulong
)*(uchar
*)p
;
35 p
= map_sysmem(addr
, sizeof(ushort
));
36 val
= (ulong
)*(ushort
*)p
;
41 p
= map_sysmem(addr
, sizeof(ulong
));
47 return simple_strtoul(s
, NULL
, 16);
55 #define SLRE_BUFSZ 16384
56 #define SLRE_PATSZ 4096
59 * memstr - Find the first substring in memory
60 * @s1: The string to be searched
61 * @s2: The string to search for
63 * Similar to and based on strstr(),
64 * but strings do not need to be NUL terminated.
66 static char *memstr(const char *s1
, int l1
, const char *s2
, int l2
)
73 if (!memcmp(s1
, s2
, l2
))
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 */
88 char *p
= memstr(string
, *slen
, old
, olen
);
93 debug("## Match at pos %ld: match len %d, subst len %d\n",
94 (long)(p
- string
), olen
, nlen
);
96 /* make sure replacement matches */
97 if (*slen
+ nlen
- olen
> ssize
) {
98 printf("## error: substitution buffer overflow\n");
102 /* move tail if needed */
106 len
= (olen
> nlen
) ? olen
: nlen
;
108 tail
= ssize
- (p
+ len
- string
);
110 debug("## tail len %d\n", tail
);
112 memmove(p
+ nlen
, p
+ olen
, tail
);
115 /* insert substitue */
116 memcpy(p
, new, nlen
);
118 *slen
+= nlen
- olen
;
124 * Perform regex operations on a environment variable
126 * Returns 0 if OK, 1 in case of errors.
128 static int regex_sub(const char *name
,
129 const char *r
, const char *s
, const char *t
,
133 char data
[SLRE_BUFSZ
];
136 int res
, len
, nlen
, loop
;
141 if (slre_compile(&slre
, r
) == 0) {
142 printf("Error compiling regex: %s\n", slre
.err_str
);
147 value
= env_get(name
);
150 printf("## Error: variable \"%s\" not defined\n", name
);
156 debug("REGEX on %s=%s\n", name
, t
);
157 debug("REGEX=\"%s\", SUBST=\"%s\", GLOBAL=%d\n",
158 r
, s
? s
: "<NULL>", global
);
161 if (len
+ 1 > SLRE_BUFSZ
) {
162 printf("## error: subst buffer overflow: have %d, need %d\n",
163 SLRE_BUFSZ
, len
+ 1);
174 for (loop
= 0;; loop
++) {
175 struct cap caps
[slre
.num_caps
+ 2];
176 char nbuf
[SLRE_PATSZ
];
181 (void) memset(caps
, 0, sizeof(caps
));
183 res
= slre_match(&slre
, datap
, len
, caps
);
185 debug("Result: %d\n", res
);
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
);
196 printf("%s: No match\n", t
);
203 debug("## MATCH ## %s\n", data
);
206 printf("%s=%s\n", name
, t
);
213 if (nlen
+ 1 >= SLRE_PATSZ
) {
214 printf("## error: pattern buffer overflow: have %d, need %d\n",
215 SLRE_BUFSZ
, nlen
+ 1);
220 debug("## SUBST(1) ## %s\n", nbuf
);
223 * Handle back references
225 * Support for \0 ... \9, where \0 is the
226 * whole matched pattern (similar to &).
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.
236 for (i
= 0; i
< 10; ++i
) {
242 if (caps
[i
].len
== 0)
247 debug("## BACKREF %d: replace \"%.*s\" by \"%.*s\" in \"%s\"\n",
250 caps
[i
].len
, caps
[i
].ptr
,
254 char *p
= memstr(np
, nlen
, backref
, 2);
259 np
= substitute(np
, &nlen
,
262 caps
[i
].ptr
, caps
[i
].len
);
268 debug("## SUBST(2) ## %s\n", nbuf
);
270 datap
= substitute(datap
, &len
, SLRE_BUFSZ
,
277 debug("## REMAINDER: %s\n", datap
);
279 debug("## RESULT: %s\n", data
);
284 debug("## FINAL (now env_set()) : %s\n", data
);
286 printf("%s=%s\n", name
, data
);
288 return env_set(name
, data
);
292 static int do_setexpr(cmd_tbl_t
*cmdtp
, int flag
, int argc
, char * const argv
[])
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
306 /* > 6 already tested by max command args */
307 if ((argc
< 3) || (argc
== 4))
308 return CMD_RET_USAGE
;
310 w
= cmd_get_data_size(argv
[0], 4);
312 a
= get_arg(argv
[2], w
);
314 /* plain assignment: "setexpr name value" */
316 env_set_hex(argv
[1], a
);
320 /* 5 or 6 args (6 args only with [g]sub) */
323 * rexep handling: "setexpr name [g]sub r s [t]"
324 * with 5 args, "t" will be NULL
326 if (strcmp(argv
[2], "gsub") == 0)
327 return regex_sub(argv
[1], argv
[3], argv
[4], argv
[5], 1);
329 if (strcmp(argv
[2], "sub") == 0)
330 return regex_sub(argv
[1], argv
[3], argv
[4], argv
[5], 0);
333 /* standard operators: "setexpr name val1 op val2" */
335 return CMD_RET_USAGE
;
337 if (strlen(argv
[3]) != 1)
338 return CMD_RET_USAGE
;
340 b
= get_arg(argv
[4], w
);
342 switch (argv
[3][0]) {
368 printf("invalid op\n");
372 env_set_hex(argv
[1], value
);
378 setexpr
, 6, 0, do_setexpr
,
379 "set environment variable as the result of eval expression",
380 "[.b, .w, .l] name [*]value1 <op> [*]value2\n"
381 " - set environment variable 'name' to the result of the evaluated\n"
382 " expression specified by <op>. <op> can be &, |, ^, +, -, *, /, %\n"
383 " size argument is only meaningful if value1 and/or value2 are\n"
384 " memory addresses (*)\n"
385 "setexpr[.b, .w, .l] name [*]value\n"
386 " - load a value into a variable"
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"
394 "setexpr name sub r s [t]\n"
395 " - Just like gsub(), but replace only the first matching substring"