u-boot/cmd/setexpr.c
Tom Rini 83d290c56f SPDX: Convert all of our single license tags to Linux Kernel style
When U-Boot started using SPDX tags we were among the early adopters and
there weren't a lot of other examples to borrow from.  So we picked the
area of the file that usually had a full license text and replaced it
with an appropriate SPDX-License-Identifier: entry.  Since then, the
Linux Kernel has adopted SPDX tags and they place it as the very first
line in a file (except where shebangs are used, then it's second line)
and with slightly different comment styles than us.

In part due to community overlap, in part due to better tag visibility
and in part for other minor reasons, switch over to that style.

This commit changes all instances where we have a single declared
license in the tag as both the before and after are identical in tag
contents.  There's also a few places where I found we did not have a tag
and have introduced one.

Signed-off-by: Tom Rini <trini@konsulko.com>
2018-05-07 09:34:12 -04:00

397 lines
7.8 KiB
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
);