avr/env.c

   1 #include "common.h"
   2 #include <string.h>
   3 #include <stdlib.h>
   4
   5 #include <avr/eeprom.h>
   6
   7 #include "config.h"
   8 #include "debug.h"
   9 #include "xmalloc.h"
  10 #include "crc.h"
  11 #include "command.h"
  12
  13 #include "env.h"
  14
  15
  16 #define ENV_SIZE        (CONFIG_ENV_SIZE - sizeof(uint16_t) -1)
  17 #define ACTIVE_FLAG     1
  18 #define OBSOLETE_FLAG   0
  19
  20 #define ENVLIST_DELETE  (1<<0)
  21
  22
  23 /*
  24  * Default Environment
  25  */
  26
  27 #define DELIM           "\0"
  28
  29 const FLASH char default_env[] = {
  30         "bootdelay="    "3"             DELIM
  31         "bootcmd="      "reset; loadf; go $(startaddr)" DELIM
  32         "baudrate="     "115200"        DELIM
  33         "startaddr="    "0"             DELIM
  34         DELIM
  35 };
  36
  37 /* EEPROM storage */
  38 typedef struct environment_s {
  39         uint16_t        crc;            /* CRC16 over data bytes        */
  40         uint8_t         flags;          /* active/obsolete flags        */
  41         char            data[ENV_SIZE]; /* Environment data             */
  42 } env_t;
  43
  44
  45 /* */
  46 typedef struct env_item_s {
  47         char * envvar;
  48 } env_item_t;
  49
  50
  51 static uint8_t env_valid;
  52 static env_item_t env_list[CONFIG_ENVVAR_MAX];
  53 static int entrycount;
  54
  55
  56 static
  57 char env_get_char(uint16_t index)
  58 {
  59         unsigned int off = CONFIG_ENV_OFFSET;
  60         char ret;
  61
  62         switch (env_valid) {
  63         case 2:
  64                 off += CONFIG_ENV_SIZE;
  65         case 1:
  66                 ret = (char) eeprom_read_byte((const uint8_t *)off + index +
  67                                 offsetof(env_t, data));
  68                 break;
  69
  70         default:
  71                 ret = default_env[index];
  72         }
  73
  74         return ret;
  75 }
  76
  77
  78 static
  79 int comp_env_items(const void *m1, const void *m2)
  80 {
  81         env_item_t *ep1 = (env_item_t *) m1;
  82         env_item_t *ep2 = (env_item_t *) m2;
  83
  84         return strcmp(ep1->envvar, ep2->envvar);
  85 }
  86
  87
  88 env_item_t *envlist_search(const MEMX char *name)
  89 {
  90         env_item_t e;
  91
  92         e.envvar = (char *) name;
  93
  94 #ifdef __MEMX
  95         char buf[CONFIG_SYS_ENV_NAMELEN+1];
  96
  97         if (__builtin_avr_flash_segment(name) != -1) {
  98                 char *p = buf;
  99                 while ((*p++ = *name++) != '\0')
 100                         ;
 101                 e.envvar = buf;
 102         }
 103 #endif /* __MEMX */
 104
 105         return bsearch(&e, env_list, entrycount,
 106                                 sizeof(env_item_t), comp_env_items);
 107 }
 108
 109
 110 static
 111 env_item_t *envlist_enter(env_item_t *e)
 112 {
 113         const size_t size = sizeof(env_item_t);
 114         env_item_t *ep;
 115
 116         ep = bsearch(e, env_list, entrycount,
 117                         size, comp_env_items);
 118
 119         if (ep == NULL) {
 120                 if (entrycount < CONFIG_ENVVAR_MAX) {
 121
 122                         env_list[entrycount++] = *e;
 123                         qsort(env_list, entrycount, size, comp_env_items);
 124                         ep = bsearch(e, env_list, entrycount,
 125                                                 size, comp_env_items);
 126                 }
 127         } else {
 128                 free(ep->envvar);
 129                 ep->envvar = e->envvar;
 130         }
 131
 132         return ep;
 133 }
 134
 135
 136 static
 137 int env_item_delete(env_item_t *ep)
 138 {
 139         if (entrycount == 0)
 140                 return -1;
 141
 142         free(ep->envvar);
 143
 144         entrycount--;
 145         size_t size = sizeof(env_item_t);
 146         memmove(ep, ep + 1, (env_list - ep)*size + entrycount*size);
 147
 148         return 0;
 149 }
 150
 151 static
 152 int envlist_delete(const char *name)
 153 {
 154         env_item_t e;
 155
 156         e.envvar = (char *) name;
 157
 158         env_item_t *ep = bsearch(&e, env_list, entrycount,
 159                                 sizeof(env_item_t), comp_env_items);
 160
 161         if (ep != NULL)
 162                 return env_item_delete(ep);
 163
 164         return 1;
 165 }
 166
 167
 168
 169 static
 170 int envlist_import(uint8_t flags)
 171 {
 172         uint16_t index;
 173
 174         int len;
 175         env_item_t e;
 176         char *np, c;
 177         uint_fast8_t ef;
 178
 179         if ((flags & ENVLIST_DELETE) != 0)
 180                 while (entrycount != 0)
 181                         env_item_delete(&env_list[entrycount-1]);
 182
 183         for (index = 0; env_get_char(index) != '\0'; ) {
 184                 for (len = 0; env_get_char(index + len) != '\0'; ++len) {
 185                         if ((index + len) >= ENV_SIZE)
 186                                 return -1;
 187                 }
 188
 189                 np = (char *) xmalloc(len+1);
 190                 if (np == NULL) {
 191                         printf_P(PSTR("## Can't malloc %d bytes\n"), len+1);
 192                         return 1;
 193                 }
 194                 e.envvar = np;
 195                 ef = 0;
 196                 while ((c = env_get_char(index++)) != '\0') {
 197                         if (!ef && (c == '=')) {
 198                                 *np = '\0';
 199                                 ef = 1;
 200                         } else
 201                                 *np = c;
 202                         np++;
 203                 }
 204                 *np = '\0';
 205                 envlist_enter(&e);
 206         }
 207
 208
 209         return 0;
 210 }
 211
 212
 213 static
 214 uint16_t env_crc(uint16_t data_offset)
 215 {
 216         uint16_t crc;
 217         uint16_t i;
 218         char c, c0;
 219
 220         crc = 0xffff;
 221         c = 0xff;
 222         for (i = 0; !(c == 0 && c0 == 0) && i < ENV_SIZE; i++)
 223         {
 224                 c0 = c;
 225                 c = eeprom_read_byte((const uint8_t *) data_offset + i);
 226                 crc = crc16(crc, c);
 227         }
 228         return crc ;
 229 }
 230
 231
 232 /**
 233  * return valid env
 234  */
 235 static
 236 int env_check_valid(void)
 237 {
 238         const uint16_t offset[2] = {CONFIG_ENV_OFFSET,
 239                                     CONFIG_ENV_OFFSET + CONFIG_ENV_SIZE};
 240         uint_fast8_t flags[2], crc_ok[2];
 241         int rc;
 242
 243         /* read FLAGS */
 244         flags[0] = eeprom_read_byte ((uint8_t *) offset[0] +
 245                                 offsetof(env_t, flags));
 246         flags[1] = eeprom_read_byte ((uint8_t *) offset[1] +
 247                                 offsetof(env_t, flags));
 248
 249         /* check CRC */
 250         crc_ok[0] = (
 251                 eeprom_read_word((uint16_t *) offset[0] +
 252                                 offsetof(env_t, crc))
 253                 == env_crc(offset[0] + offsetof(env_t, data))
 254         );
 255         crc_ok[1] = (
 256                 eeprom_read_word((uint16_t *) offset[1] +
 257                                 offsetof(env_t, crc))
 258                 == env_crc(offset[1] + offsetof(env_t, data))
 259         );
 260
 261         if (!crc_ok[0] && !crc_ok[1]) {
 262                 rc = 0;
 263
 264         } else if (crc_ok[0] && !crc_ok[1]) {
 265                 rc = 1;
 266         } else if (!crc_ok[0] && crc_ok[1]) {
 267                 rc = 2;
 268         } else {
 269                 /* both ok - check serial */
 270 #if 1
 271                 if      (flags[1] == ACTIVE_FLAG && flags[0] != ACTIVE_FLAG)
 272                         rc = 2;
 273                 else if (flags[1] == OBSOLETE_FLAG && flags[0] == 0xFF)
 274                         rc = 2;
 275                 else
 276                         rc = 1;
 277 #else
 278                 if (flags[0] == ACTIVE_FLAG && flags[1] == OBSOLETE_FLAG)
 279                         rc = 1;
 280                 else if (flags[0] == OBSOLETE_FLAG && flags[1] == ACTIVE_FLAG)
 281                         rc = 2;
 282                 else if (flags[0] == 0xFF && flags[1] == 0)
 283                         rc = 2;
 284                 else if (flags[1] == 0xFF && flags[0] == 0)
 285                         rc = 1;
 286                 else /* flags are equal - almost impossible */
 287                         rc = 1;
 288 #endif
 289         }
 290
 291         return rc;
 292 }
 293
 294
 295 int env_init(void)
 296 {
 297         env_valid = env_check_valid();
 298         if (env_valid == 0) {
 299                 printf_P(PSTR("*** Warning - bad CRC, "
 300                                 "using default environment\n\n"));
 301         }
 302
 303         envlist_import(ENVLIST_DELETE);
 304         return 0;
 305 }
 306
 307
 308 char *getenv(const MEMX char *name)
 309 {
 310         env_item_t *ep;
 311         char *ret = NULL;
 312
 313         ep = envlist_search(name);
 314         if (ep != NULL)
 315                 ret = ep->envvar + strlen(ep->envvar) +1;
 316         return ret;
 317 }
 318
 319 static
 320 int env_item_save(env_item_t *ep, uint16_t offset, int space_left)
 321 {
 322         int nlen, vlen;
 323         char *var = ep->envvar;
 324
 325         nlen = strlen(var);
 326         if (nlen == 0)
 327                 return 0;
 328         vlen = strlen(var + nlen + 1);
 329         if (vlen == 0)
 330                 return 0;
 331         if (nlen + vlen + 2 > space_left)
 332                 return 0;
 333
 334         eeprom_update_block(var, (uint8_t *) offset, nlen);
 335         offset += nlen;
 336         eeprom_update_byte((uint8_t *) offset++, '=');
 337         eeprom_update_block(var + nlen +1, (uint8_t *) offset, vlen+1);
 338
 339         return nlen + vlen + 2;
 340 }
 341
 342
 343 static
 344 int saveenv(void)
 345 {
 346         unsigned int off     = CONFIG_ENV_OFFSET + CONFIG_ENV_SIZE;
 347         unsigned int off_red = CONFIG_ENV_OFFSET;
 348         unsigned int pos;
 349         int len, left;
 350         uint16_t crc;
 351         int rc = 0;
 352
 353         if (env_valid == 2) {
 354                 off     = CONFIG_ENV_OFFSET;
 355                 off_red = CONFIG_ENV_OFFSET + CONFIG_ENV_SIZE;
 356         }
 357
 358         eeprom_update_byte((uint8_t *) off + offsetof(env_t, flags), 0xff);
 359
 360         pos = off + offsetof(env_t, data);
 361         left = ENV_SIZE - 1;
 362         for (int i = 0 ; i < entrycount; i++) {
 363                 len = env_item_save(&env_list[i], pos, left);
 364                 if (len == 0) {
 365                         return 1;
 366                 }
 367                 pos += len;
 368                 left -= len;
 369         }
 370         /* terminate list */
 371         eeprom_update_byte((uint8_t *) pos, 0);
 372         crc = env_crc(off + offsetof(env_t, data));
 373         eeprom_update_word((uint16_t *) off + offsetof(env_t, crc), crc);
 374         eeprom_update_byte((uint8_t *) off + offsetof(env_t, flags),
 375                                         ACTIVE_FLAG);
 376
 377         if (rc == 0) {
 378                 eeprom_update_byte((uint8_t *) off_red + offsetof(env_t, flags),
 379                                         OBSOLETE_FLAG);
 380                 env_valid = (env_valid == 2) ? 1 : 2;
 381         }
 382
 383         return rc;
 384 }
 385
 386
 387 static
 388 int env_item_print(env_item_t *ep)
 389 {
 390         int len;
 391         char *ev = ep->envvar;
 392
 393         len = printf_P(PSTR("%s="), ev);
 394         len += printf_P(PSTR("%s\n"), ev + len);
 395
 396         return len;
 397 }
 398
 399
 400 /*
 401  * Command interface: print one or all environment variables
 402  *
 403  * Returns -1 in case of error, or length of printed string
 404  */
 405 static
 406 int env_print(const MEMX char *name)
 407 {
 408         int len = -1;
 409
 410         if (name) {             /* print a single name */
 411
 412                 env_item_t *ep = envlist_search(name);
 413                 if (ep != NULL)
 414                         len = env_item_print(ep);
 415
 416         } else {                /* print whole list */
 417                 len = 0;
 418                 for (int i = 0 ; i < entrycount; i++) {
 419                         len += env_item_print(&env_list[i]);
 420                 }
 421         }
 422         return len;
 423 }
 424
 425
 426 command_ret_t do_env_print(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 427 {
 428         command_ret_t rc = CMD_RET_SUCCESS;
 429
 430         (void) cmdtp; (void) flag;
 431
 432         if (argc == 1) {
 433                 /* print all env vars */
 434                 int size = env_print(NULL);
 435                 if (size < 0)
 436                         return CMD_RET_FAILURE;
 437                 printf_P(PSTR("\nEnvironment size: %d/%d bytes\n"),
 438                         size, ENV_SIZE);
 439                 return CMD_RET_SUCCESS;
 440         }
 441
 442         /* print selected env vars */
 443         for (int i = 1; i < argc; ++i) {
 444                 int rc = env_print(argv[i]);
 445                 if (rc < 0) {
 446                         printf_P(PSTR("## Error: \"%s\" not defined\n"), argv[i]);
 447                         rc = CMD_RET_FAILURE;
 448                 }
 449         }
 450
 451         return rc;
 452 }
 453
 454
 455 /**
 456  * Set or delete environment variable
 457  *
 458  * Set a new environment variable,
 459  * or replace or delete an existing one.
 460  *
 461  * @param flag          (not used)
 462  * @param argc
 463  * @param argv[1]       Environment variable to set or delete
 464  *                      if no more args
 465  * @param argv[2] ...   Value to set it to
 466  *
 467  * @return 0 if ok, 1 on error
 468  */
 469 static
 470 command_ret_t _do_env_set(int flag, int argc, char * const argv[])
 471 {
 472         int i, len;
 473         char *name, *value, *valp, *p;
 474         env_item_t e, *ep;
 475
 476         (void) flag;
 477         debug("Initial value for argc=%d\n", argc);
 478
 479         name = argv[1];
 480         value = argv[2];
 481
 482         if (strchr(name, '=')) {
 483                 printf_P(PSTR("## Error: illegal character '='"
 484                        "in variable name \"%s\"\n"), name);
 485                 return CMD_RET_FAILURE;
 486         }
 487         len = strlen(name);
 488         if (len > CONFIG_SYS_ENV_NAMELEN) {
 489                 printf_P(PSTR("## Error: Variable name \"%s\" too long. "
 490                        "(max %d characters)\n"), name, CONFIG_SYS_ENV_NAMELEN);
 491                 return CMD_RET_FAILURE;
 492         }
 493 /*
 494         env_id++;
 495 */
 496         /* Delete only ? */
 497         if (argc < 3 || argv[2] == NULL) {
 498                 int rc = envlist_delete(name);
 499                 return rc ? CMD_RET_FAILURE : CMD_RET_SUCCESS;
 500         }
 501
 502         /*
 503          * Insert / replace new value
 504          */
 505         for (i = 2, len += 1; i < argc; ++i)
 506                 len += strlen(argv[i]) + 1;
 507
 508         value = xmalloc(len);
 509         if (value == NULL) {
 510                 printf_P(PSTR("## Can't malloc %d bytes\n"), len);
 511                 return CMD_RET_FAILURE;
 512         }
 513         strcpy(value, name);
 514         valp = value + strlen(name) + 1;
 515         for (i = 2, p = valp; i < argc; ++i) {
 516                 char *v = argv[i];
 517
 518                 while ((*p++ = *v++) != '\0')
 519                         ;
 520                 *(p - 1) = ' ';
 521         }
 522         if (p != valp)
 523                 *--p = '\0';
 524
 525         e.envvar = value;
 526         ep = envlist_enter(&e);
 527         if (!ep) {
 528                 printf_P(PSTR("## Error inserting \"%s\" variable.\n"),
 529                         name);
 530                 return CMD_RET_FAILURE;
 531         }
 532
 533         return CMD_RET_SUCCESS;
 534 }
 535
 536 /**
 537  * Set an environment variable
 538  *
 539  * @param varname       Environment variable to set
 540  * @param varvalue      Value to set it to
 541  * @return 0 if ok, 1 on error
 542  */
 543 static
 544 int setenv(const char *varname, const char *varvalue)
 545 {
 546         const char * const argv[3] = { NULL, varname, varvalue };
 547         int argc = 3;
 548
 549         if (varvalue == NULL || varvalue[0] == '\0')
 550                 --argc;
 551
 552         return (int) _do_env_set(0, argc, (char * const *)argv);
 553 }
 554
 555 #if 0
 556 /**
 557  * Set an environment variable to an integer value
 558  *
 559  * @param varname       Environment variable to set
 560  * @param value         Value to set it to
 561  * @return 0 if ok, 1 on error
 562  */
 563 int setenv_ulong(const char *varname, unsigned long value)
 564 {
 565         /* TODO: this should be unsigned */
 566         char *str = simple_itoa(value);
 567
 568         return setenv(varname, str);
 569 }
 570 #endif
 571
 572
 573 /**
 574  * Set an environment variable to an value in hex
 575  *
 576  * @param varname       Environment variable to set
 577  * @param value         Value to set it to
 578  * @return 0 if ok, 1 on error
 579  */
 580 int setenv_hex(const MEMX char *varname, unsigned long value)
 581 {
 582         char str[sizeof(unsigned long) *2 + 1];
 583
 584         sprintf_P(str, PSTR("%lx"), value);
 585         return setenv(varname, str);
 586 }
 587
 588
 589 /**
 590  * Decode the integer value of an environment variable and return it.
 591  *
 592  * @param name          Name of environemnt variable
 593  * @param base          Number base to use (normally 10, or 16 for hex)
 594  * @param default_val   Default value to return if the variable is not
 595  *                      found
 596  * @return the decoded value, or default_val if not found
 597  */
 598 unsigned long getenv_ulong(const MEMX char *name, int base, unsigned long default_val)
 599 {
 600         unsigned long value;
 601         char *vp, *endp;
 602
 603         env_item_t *ep = envlist_search(name);
 604
 605         if (ep != NULL ) {
 606                 vp = ep->envvar + strlen(ep->envvar) +1;
 607                 value = strtoul(vp, &endp, base);
 608                 if (endp != vp)
 609                         return value;
 610         }
 611
 612         return default_val;
 613 }
 614
 615
 616 command_ret_t do_env_set(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 617 {
 618         (void) cmdtp;
 619
 620         if (argc < 2)
 621                 return CMD_RET_USAGE;
 622
 623         return _do_env_set(flag, argc, argv);
 624 }
 625
 626
 627 command_ret_t do_env_default(cmd_tbl_t *cmdtp, int flag,
 628                           int argc, char * const argv[])
 629 {
 630         (void) cmdtp; (void) flag; (void) argc; (void) argv;
 631
 632         uint8_t tmp = env_valid;
 633         env_valid = 0;
 634
 635         /* Reset the whole environment */
 636         printf_P(PSTR("## Resetting to default environment\n"));
 637         envlist_import(ENVLIST_DELETE);
 638
 639         env_valid = tmp;
 640
 641         return CMD_RET_SUCCESS;
 642 }
 643
 644
 645 command_ret_t do_env_save(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 646 {
 647         (void) cmdtp; (void) flag; (void) argc; (void) argv;
 648
 649         printf_P(PSTR("Saving Environment ...\n"));
 650         return saveenv() ? CMD_RET_FAILURE : CMD_RET_SUCCESS;
 651 }
 652
 653
 654 #if defined(CONFIG_AUTO_COMPLETE)
 655 int env_complete(char *var, int maxv, char *cmdv[], int bufsz, char *buf)
 656 {
 657         ENTRY *match;
 658         int found, idx;
 659
 660         idx = 0;
 661         found = 0;
 662         cmdv[0] = NULL;
 663
 664         while ((idx = hmatch_r(var, idx, &match, &env_htab))) {
 665                 int vallen = strlen(match->key) + 1;
 666
 667                 if (found >= maxv - 2 || bufsz < vallen)
 668                         break;
 669
 670                 cmdv[found++] = buf;
 671                 memcpy(buf, match->key, vallen);
 672                 buf += vallen;
 673                 bufsz -= vallen;
 674         }
 675
 676         qsort(cmdv, found, sizeof(cmdv[0]), strcmp_compar);
 677
 678         if (idx)
 679                 cmdv[found++] = "...";
 680
 681         cmdv[found] = NULL;
 682         return found;
 683 }
 684 #endif