common.c 6.2 KB

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  1. // SPDX-License-Identifier: GPL-2.0+
  2. /*
  3. * (C) Copyright 2000-2010
  4. * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
  5. *
  6. * (C) Copyright 2001 Sysgo Real-Time Solutions, GmbH <www.elinos.com>
  7. * Andreas Heppel <aheppel@sysgo.de>
  8. */
  9. #include <common.h>
  10. #include <command.h>
  11. #include <environment.h>
  12. #include <linux/stddef.h>
  13. #include <search.h>
  14. #include <errno.h>
  15. #include <malloc.h>
  16. DECLARE_GLOBAL_DATA_PTR;
  17. /************************************************************************
  18. * Default settings to be used when no valid environment is found
  19. */
  20. #include <env_default.h>
  21. struct hsearch_data env_htab = {
  22. .change_ok = env_flags_validate,
  23. };
  24. /*
  25. * Read an environment variable as a boolean
  26. * Return -1 if variable does not exist (default to true)
  27. */
  28. int env_get_yesno(const char *var)
  29. {
  30. char *s = env_get(var);
  31. if (s == NULL)
  32. return -1;
  33. return (*s == '1' || *s == 'y' || *s == 'Y' || *s == 't' || *s == 'T') ?
  34. 1 : 0;
  35. }
  36. /*
  37. * Look up the variable from the default environment
  38. */
  39. char *env_get_default(const char *name)
  40. {
  41. char *ret_val;
  42. unsigned long really_valid = gd->env_valid;
  43. unsigned long real_gd_flags = gd->flags;
  44. /* Pretend that the image is bad. */
  45. gd->flags &= ~GD_FLG_ENV_READY;
  46. gd->env_valid = ENV_INVALID;
  47. ret_val = env_get(name);
  48. gd->env_valid = really_valid;
  49. gd->flags = real_gd_flags;
  50. return ret_val;
  51. }
  52. void set_default_env(const char *s)
  53. {
  54. int flags = 0;
  55. if (sizeof(default_environment) > ENV_SIZE) {
  56. puts("*** Error - default environment is too large\n\n");
  57. return;
  58. }
  59. if (s) {
  60. if (*s == '!') {
  61. printf("*** Warning - %s, "
  62. "using default environment\n\n",
  63. s + 1);
  64. } else {
  65. flags = H_INTERACTIVE;
  66. puts(s);
  67. }
  68. } else {
  69. debug("Using default environment\n");
  70. }
  71. if (himport_r(&env_htab, (char *)default_environment,
  72. sizeof(default_environment), '\0', flags, 0,
  73. 0, NULL) == 0)
  74. pr_err("Environment import failed: errno = %d\n", errno);
  75. gd->flags |= GD_FLG_ENV_READY;
  76. gd->flags |= GD_FLG_ENV_DEFAULT;
  77. }
  78. /* [re]set individual variables to their value in the default environment */
  79. int set_default_vars(int nvars, char * const vars[])
  80. {
  81. /*
  82. * Special use-case: import from default environment
  83. * (and use \0 as a separator)
  84. */
  85. return himport_r(&env_htab, (const char *)default_environment,
  86. sizeof(default_environment), '\0',
  87. H_NOCLEAR | H_INTERACTIVE, 0, nvars, vars);
  88. }
  89. /*
  90. * Check if CRC is valid and (if yes) import the environment.
  91. * Note that "buf" may or may not be aligned.
  92. */
  93. int env_import(const char *buf, int check)
  94. {
  95. env_t *ep = (env_t *)buf;
  96. if (check) {
  97. uint32_t crc;
  98. memcpy(&crc, &ep->crc, sizeof(crc));
  99. if (crc32(0, ep->data, ENV_SIZE) != crc) {
  100. set_default_env("!bad CRC");
  101. return -EIO;
  102. }
  103. }
  104. if (himport_r(&env_htab, (char *)ep->data, ENV_SIZE, '\0', 0, 0,
  105. 0, NULL)) {
  106. gd->flags |= GD_FLG_ENV_READY;
  107. return 0;
  108. }
  109. pr_err("Cannot import environment: errno = %d\n", errno);
  110. set_default_env("!import failed");
  111. return -EIO;
  112. }
  113. #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
  114. static unsigned char env_flags;
  115. int env_import_redund(const char *buf1, int buf1_read_fail,
  116. const char *buf2, int buf2_read_fail)
  117. {
  118. int crc1_ok, crc2_ok;
  119. env_t *ep, *tmp_env1, *tmp_env2;
  120. tmp_env1 = (env_t *)buf1;
  121. tmp_env2 = (env_t *)buf2;
  122. if (buf1_read_fail && buf2_read_fail) {
  123. puts("*** Error - No Valid Environment Area found\n");
  124. } else if (buf1_read_fail || buf2_read_fail) {
  125. puts("*** Warning - some problems detected ");
  126. puts("reading environment; recovered successfully\n");
  127. }
  128. if (buf1_read_fail && buf2_read_fail) {
  129. set_default_env("!bad env area");
  130. return -EIO;
  131. } else if (!buf1_read_fail && buf2_read_fail) {
  132. gd->env_valid = ENV_VALID;
  133. return env_import((char *)tmp_env1, 1);
  134. } else if (buf1_read_fail && !buf2_read_fail) {
  135. gd->env_valid = ENV_REDUND;
  136. return env_import((char *)tmp_env2, 1);
  137. }
  138. crc1_ok = crc32(0, tmp_env1->data, ENV_SIZE) ==
  139. tmp_env1->crc;
  140. crc2_ok = crc32(0, tmp_env2->data, ENV_SIZE) ==
  141. tmp_env2->crc;
  142. if (!crc1_ok && !crc2_ok) {
  143. set_default_env("!bad CRC");
  144. return -EIO;
  145. } else if (crc1_ok && !crc2_ok) {
  146. gd->env_valid = ENV_VALID;
  147. } else if (!crc1_ok && crc2_ok) {
  148. gd->env_valid = ENV_REDUND;
  149. } else {
  150. /* both ok - check serial */
  151. if (tmp_env1->flags == 255 && tmp_env2->flags == 0)
  152. gd->env_valid = ENV_REDUND;
  153. else if (tmp_env2->flags == 255 && tmp_env1->flags == 0)
  154. gd->env_valid = ENV_VALID;
  155. else if (tmp_env1->flags > tmp_env2->flags)
  156. gd->env_valid = ENV_VALID;
  157. else if (tmp_env2->flags > tmp_env1->flags)
  158. gd->env_valid = ENV_REDUND;
  159. else /* flags are equal - almost impossible */
  160. gd->env_valid = ENV_VALID;
  161. }
  162. if (gd->env_valid == ENV_VALID)
  163. ep = tmp_env1;
  164. else
  165. ep = tmp_env2;
  166. env_flags = ep->flags;
  167. return env_import((char *)ep, 0);
  168. }
  169. #endif /* CONFIG_SYS_REDUNDAND_ENVIRONMENT */
  170. /* Export the environment and generate CRC for it. */
  171. int env_export(env_t *env_out)
  172. {
  173. char *res;
  174. ssize_t len;
  175. res = (char *)env_out->data;
  176. len = hexport_r(&env_htab, '\0', 0, &res, ENV_SIZE, 0, NULL);
  177. if (len < 0) {
  178. pr_err("Cannot export environment: errno = %d\n", errno);
  179. return 1;
  180. }
  181. env_out->crc = crc32(0, env_out->data, ENV_SIZE);
  182. #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
  183. env_out->flags = ++env_flags; /* increase the serial */
  184. #endif
  185. return 0;
  186. }
  187. void env_relocate(void)
  188. {
  189. #if defined(CONFIG_NEEDS_MANUAL_RELOC)
  190. env_reloc();
  191. env_fix_drivers();
  192. env_htab.change_ok += gd->reloc_off;
  193. #endif
  194. if (gd->env_valid == ENV_INVALID) {
  195. #if defined(CONFIG_ENV_IS_NOWHERE) || defined(CONFIG_SPL_BUILD)
  196. /* Environment not changable */
  197. set_default_env(NULL);
  198. #else
  199. bootstage_error(BOOTSTAGE_ID_NET_CHECKSUM);
  200. set_default_env("!bad CRC");
  201. #endif
  202. } else {
  203. env_load();
  204. }
  205. }
  206. #if defined(CONFIG_AUTO_COMPLETE) && !defined(CONFIG_SPL_BUILD)
  207. int env_complete(char *var, int maxv, char *cmdv[], int bufsz, char *buf)
  208. {
  209. ENTRY *match;
  210. int found, idx;
  211. idx = 0;
  212. found = 0;
  213. cmdv[0] = NULL;
  214. while ((idx = hmatch_r(var, idx, &match, &env_htab))) {
  215. int vallen = strlen(match->key) + 1;
  216. if (found >= maxv - 2 || bufsz < vallen)
  217. break;
  218. cmdv[found++] = buf;
  219. memcpy(buf, match->key, vallen);
  220. buf += vallen;
  221. bufsz -= vallen;
  222. }
  223. qsort(cmdv, found, sizeof(cmdv[0]), strcmp_compar);
  224. if (idx)
  225. cmdv[found++] = "...";
  226. cmdv[found] = NULL;
  227. return found;
  228. }
  229. #endif