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Diffstat (limited to 'roms/u-boot/cmd/setexpr.c')
-rw-r--r-- | roms/u-boot/cmd/setexpr.c | 518 |
1 files changed, 518 insertions, 0 deletions
diff --git a/roms/u-boot/cmd/setexpr.c b/roms/u-boot/cmd/setexpr.c new file mode 100644 index 000000000..e828be397 --- /dev/null +++ b/roms/u-boot/cmd/setexpr.c @@ -0,0 +1,518 @@ +// 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 <env.h> +#include <log.h> +#include <malloc.h> +#include <mapmem.h> +#include <linux/sizes.h> + +/** + * struct expr_arg: Holds an argument to an expression + * + * @ival: Integer value (if width is not CMD_DATA_SIZE_STR) + * @sval: String value (if width is CMD_DATA_SIZE_STR) + */ +struct expr_arg { + union { + ulong ival; + char *sval; + }; +}; + +static int get_arg(char *s, int w, struct expr_arg *argp) +{ + struct expr_arg arg; + + /* + * 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; + int len; + char *str; + + addr = simple_strtoul(&s[1], NULL, 16); + switch (w) { + case 1: + p = map_sysmem(addr, sizeof(uchar)); + val = (ulong)*(uchar *)p; + unmap_sysmem(p); + arg.ival = val; + break; + case 2: + p = map_sysmem(addr, sizeof(ushort)); + val = (ulong)*(ushort *)p; + unmap_sysmem(p); + arg.ival = val; + break; + case CMD_DATA_SIZE_STR: + p = map_sysmem(addr, SZ_64K); + + /* Maximum string length of 64KB plus terminator */ + len = strnlen((char *)p, SZ_64K) + 1; + str = malloc(len); + if (!str) { + printf("Out of memory\n"); + return -ENOMEM; + } + memcpy(str, p, len); + str[len - 1] = '\0'; + unmap_sysmem(p); + arg.sval = str; + break; + case 4: + p = map_sysmem(addr, sizeof(u32)); + val = *(u32 *)p; + unmap_sysmem(p); + arg.ival = val; + break; + default: + p = map_sysmem(addr, sizeof(ulong)); + val = *p; + unmap_sysmem(p); + arg.ival = val; + break; + } + } else { + if (w == CMD_DATA_SIZE_STR) + return -EINVAL; + arg.ival = simple_strtoul(s, NULL, 16); + } + *argp = arg; + + return 0; +} + +#ifdef CONFIG_REGEX + +#include <slre.h> + +/* + * 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; +} + +/** + * substitute() - Substitute part of one string with another + * + * This updates @string so that the first occurrence of @old is replaced with + * @new + * + * @string: String buffer containing string to update at the start + * @slen: Pointer to current string length, updated on success + * @ssize: Size of string buffer + * @old: Old string to find in the buffer (no terminator needed) + * @olen: Length of @old excluding terminator + * @new: New string to replace @old with + * @nlen: Length of @new excluding terminator + * @return pointer to immediately after the copied @new in @string, or NULL if + * no replacement took place + */ +static char *substitute(char *string, int *slen, int ssize, + const char *old, int olen, const char *new, int nlen) +{ + 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 substitute */ + memcpy(p, new, nlen); + + *slen += nlen - olen; + + return p + nlen; +} + +int setexpr_regex_sub(char *data, uint data_size, char *nbuf, uint nbuf_size, + const char *r, const char *s, bool global) +{ + struct slre slre; + char *datap = data; + int res, len, nlen, loop; + + if (slre_compile(&slre, r) == 0) { + printf("Error compiling regex: %s\n", slre.err_str); + return 1; + } + + len = strlen(data); + for (loop = 0;; loop++) { + struct cap caps[slre.num_caps + 2]; + const char *old; + char *np; + int i, olen; + + (void) memset(caps, 0, sizeof(caps)); + + res = slre_match(&slre, datap, len - (datap - data), 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", data); + return 1; + } else { + break; + } + } + + debug("## MATCH ## %s\n", data); + + if (!s) + return 1; + + old = caps[0].ptr; + olen = caps[0].len; + nlen = strlen(s); + + if (nlen + 1 >= nbuf_size) { + printf("## error: pattern buffer overflow: have %d, need %d\n", + nbuf_size, 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, + nbuf_size - (np - nbuf), + backref, 2, + caps[i].ptr, caps[i].len); + + if (np == NULL) + return 1; + } + } + debug("## SUBST(2) ## %s\n", nbuf); + + datap = substitute(datap, &len, data_size - (datap - data), + 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); + + return 0; +} + +#define SLRE_BUFSZ 16384 +#define SLRE_PATSZ 4096 + +/* + * Perform regex operations on a environment variable + * + * Returns 0 if OK, 1 in case of errors. + */ +static int regex_sub_var(const char *name, const char *r, const char *s, + const char *t, int global) +{ + struct slre slre; + char data[SLRE_BUFSZ]; + char nbuf[SLRE_PATSZ]; + const char *value; + int len; + int ret; + + if (!name) + return 1; + + if (slre_compile(&slre, r) == 0) { + printf("Error compiling regex: %s\n", slre.err_str); + return 1; + } + + if (!t) { + value = env_get(name); + if (!value) { + 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); + + ret = setexpr_regex_sub(data, SLRE_BUFSZ, nbuf, SLRE_PATSZ, r, s, + global); + if (ret) + return 1; + + printf("%s=%s\n", name, data); + + return env_set(name, data); +} +#endif + +static int do_setexpr(struct cmd_tbl *cmdtp, int flag, int argc, + char *const argv[]) +{ + struct expr_arg aval, bval; + ulong value; + int ret = 0; + 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); + + if (get_arg(argv[2], w, &aval)) + return CMD_RET_FAILURE; + + /* plain assignment: "setexpr name value" */ + if (argc == 3) { + if (w == CMD_DATA_SIZE_STR) { + ret = env_set(argv[1], aval.sval); + free(aval.sval); + } else { + ret = env_set_hex(argv[1], aval.ival); + } + + return ret; + } + + /* 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_var(argv[1], argv[3], argv[4], argv[5], 1); + + if (strcmp(argv[2], "sub") == 0) + return regex_sub_var(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; + + if (get_arg(argv[4], w, &bval)) { + if (w == CMD_DATA_SIZE_STR) + free(aval.sval); + return CMD_RET_FAILURE; + } + + if (w == CMD_DATA_SIZE_STR) { + int len; + char *str; + + switch (argv[3][0]) { + case '+': + len = strlen(aval.sval) + strlen(bval.sval) + 1; + str = malloc(len); + if (!str) { + printf("Out of memory\n"); + ret = CMD_RET_FAILURE; + } else { + /* These were copied out and checked earlier */ + strcpy(str, aval.sval); + strcat(str, bval.sval); + ret = env_set(argv[1], str); + if (ret) + printf("Could not set var\n"); + free(str); + } + break; + default: + printf("invalid op\n"); + ret = 1; + } + } else { + ulong a = aval.ival; + ulong b = bval.ival; + + 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); + } + + if (w == CMD_DATA_SIZE_STR) { + free(aval.sval); + free(bval.sval); + } + + return ret; +} + +U_BOOT_CMD( + setexpr, 6, 0, do_setexpr, + "set environment variable as the result of eval expression", + "[.b, .w, .l, .s] name [*]value1 <op> [*]value2\n" + " - set environment variable 'name' to the result of the evaluated\n" + " expression specified by <op>. <op> can be &, |, ^, +, -, *, /, %\n" + " (for strings only + is supported)\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 +); |