1 // SPDX-License-Identifier: GPL-2.0+
3 * (C) Copyright 2000-2010
4 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
6 * (C) Copyright 2001 Sysgo Real-Time Solutions, GmbH <www.elinos.com>
7 * Andreas Heppel <aheppel@sysgo.de>
13 #include <env_internal.h>
14 #include <linux/stddef.h>
18 #include <u-boot/crc.h>
20 DECLARE_GLOBAL_DATA_PTR;
22 /************************************************************************
23 * Default settings to be used when no valid environment is found
25 #include <env_default.h>
27 struct hsearch_data env_htab = {
28 .change_ok = env_flags_validate,
32 * Read an environment variable as a boolean
33 * Return -1 if variable does not exist (default to true)
35 int env_get_yesno(const char *var)
37 char *s = env_get(var);
41 return (*s == '1' || *s == 'y' || *s == 'Y' || *s == 't' || *s == 'T') ?
46 * Look up the variable from the default environment
48 char *env_get_default(const char *name)
51 unsigned long really_valid = gd->env_valid;
52 unsigned long real_gd_flags = gd->flags;
54 /* Pretend that the image is bad. */
55 gd->flags &= ~GD_FLG_ENV_READY;
56 gd->env_valid = ENV_INVALID;
57 ret_val = env_get(name);
58 gd->env_valid = really_valid;
59 gd->flags = real_gd_flags;
63 void env_set_default(const char *s, int flags)
65 if (sizeof(default_environment) > ENV_SIZE) {
66 puts("*** Error - default environment is too large\n\n");
71 if ((flags & H_INTERACTIVE) == 0) {
72 printf("*** Warning - %s, "
73 "using default environment\n\n", s);
78 debug("Using default environment\n");
81 if (himport_r(&env_htab, (char *)default_environment,
82 sizeof(default_environment), '\0', flags, 0,
84 pr_err("## Error: Environment import failed: errno = %d\n",
87 gd->flags |= GD_FLG_ENV_READY;
88 gd->flags |= GD_FLG_ENV_DEFAULT;
92 /* [re]set individual variables to their value in the default environment */
93 int env_set_default_vars(int nvars, char * const vars[], int flags)
96 * Special use-case: import from default environment
97 * (and use \0 as a separator)
100 return himport_r(&env_htab, (const char *)default_environment,
101 sizeof(default_environment), '\0',
102 flags, 0, nvars, vars);
106 * Check if CRC is valid and (if yes) import the environment.
107 * Note that "buf" may or may not be aligned.
109 int env_import(const char *buf, int check)
111 env_t *ep = (env_t *)buf;
116 memcpy(&crc, &ep->crc, sizeof(crc));
118 if (crc32(0, ep->data, ENV_SIZE) != crc) {
119 env_set_default("bad CRC", 0);
120 return -ENOMSG; /* needed for env_load() */
124 if (himport_r(&env_htab, (char *)ep->data, ENV_SIZE, '\0', 0, 0,
126 gd->flags |= GD_FLG_ENV_READY;
130 pr_err("Cannot import environment: errno = %d\n", errno);
132 env_set_default("import failed", 0);
137 #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
138 static unsigned char env_flags;
140 int env_import_redund(const char *buf1, int buf1_read_fail,
141 const char *buf2, int buf2_read_fail)
143 int crc1_ok, crc2_ok;
144 env_t *ep, *tmp_env1, *tmp_env2;
146 tmp_env1 = (env_t *)buf1;
147 tmp_env2 = (env_t *)buf2;
149 if (buf1_read_fail && buf2_read_fail) {
150 puts("*** Error - No Valid Environment Area found\n");
151 } else if (buf1_read_fail || buf2_read_fail) {
152 puts("*** Warning - some problems detected ");
153 puts("reading environment; recovered successfully\n");
156 if (buf1_read_fail && buf2_read_fail) {
157 env_set_default("bad env area", 0);
159 } else if (!buf1_read_fail && buf2_read_fail) {
160 gd->env_valid = ENV_VALID;
161 return env_import((char *)tmp_env1, 1);
162 } else if (buf1_read_fail && !buf2_read_fail) {
163 gd->env_valid = ENV_REDUND;
164 return env_import((char *)tmp_env2, 1);
167 crc1_ok = crc32(0, tmp_env1->data, ENV_SIZE) ==
169 crc2_ok = crc32(0, tmp_env2->data, ENV_SIZE) ==
172 if (!crc1_ok && !crc2_ok) {
173 env_set_default("bad CRC", 0);
174 return -ENOMSG; /* needed for env_load() */
175 } else if (crc1_ok && !crc2_ok) {
176 gd->env_valid = ENV_VALID;
177 } else if (!crc1_ok && crc2_ok) {
178 gd->env_valid = ENV_REDUND;
180 /* both ok - check serial */
181 if (tmp_env1->flags == 255 && tmp_env2->flags == 0)
182 gd->env_valid = ENV_REDUND;
183 else if (tmp_env2->flags == 255 && tmp_env1->flags == 0)
184 gd->env_valid = ENV_VALID;
185 else if (tmp_env1->flags > tmp_env2->flags)
186 gd->env_valid = ENV_VALID;
187 else if (tmp_env2->flags > tmp_env1->flags)
188 gd->env_valid = ENV_REDUND;
189 else /* flags are equal - almost impossible */
190 gd->env_valid = ENV_VALID;
193 if (gd->env_valid == ENV_VALID)
198 env_flags = ep->flags;
199 return env_import((char *)ep, 0);
201 #endif /* CONFIG_SYS_REDUNDAND_ENVIRONMENT */
203 /* Export the environment and generate CRC for it. */
204 int env_export(env_t *env_out)
209 res = (char *)env_out->data;
210 len = hexport_r(&env_htab, '\0', 0, &res, ENV_SIZE, 0, NULL);
212 pr_err("Cannot export environment: errno = %d\n", errno);
216 env_out->crc = crc32(0, env_out->data, ENV_SIZE);
218 #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
219 env_out->flags = ++env_flags; /* increase the serial */
225 void env_relocate(void)
227 #if defined(CONFIG_NEEDS_MANUAL_RELOC)
230 env_htab.change_ok += gd->reloc_off;
232 if (gd->env_valid == ENV_INVALID) {
233 #if defined(CONFIG_ENV_IS_NOWHERE) || defined(CONFIG_SPL_BUILD)
234 /* Environment not changable */
235 env_set_default(NULL, 0);
237 bootstage_error(BOOTSTAGE_ID_NET_CHECKSUM);
238 env_set_default("bad CRC", 0);
245 #ifdef CONFIG_AUTO_COMPLETE
246 int env_complete(char *var, int maxv, char *cmdv[], int bufsz, char *buf,
249 struct env_entry *match;
254 * When doing $ completion, the first character should
255 * obviously be a '$'.
263 * The second one, if present, should be a '{', as some
264 * configuration of the u-boot shell expand ${var} but not
269 else if (var[0] != '\0')
278 while ((idx = hmatch_r(var, idx, &match, &env_htab))) {
279 int vallen = strlen(match->key) + 1;
281 if (found >= maxv - 2 ||
282 bufsz < vallen + (dollar_comp ? 3 : 0))
287 /* Add the '${' prefix to each var when doing $ completion. */
294 memcpy(buf, match->key, vallen);
300 * This one is a bit odd: vallen already contains the
301 * '\0' character but we need to add the '}' suffix,
302 * hence the buf - 1 here. strcpy() will add the '\0'
303 * character just after '}'. buf is then incremented
304 * to account for the extra '}' we just added.
306 strcpy(buf - 1, "}");
311 qsort(cmdv, found, sizeof(cmdv[0]), strcmp_compar);
314 cmdv[found++] = dollar_comp ? "${...}" : "...";