avr/env.c

   1 #include "common.h"
   2 #include <string.h>
   3 #include <stdlib.h>
   4 #include <avr/eeprom.h>
   5
   6 #include "config.h"
   7 #include "debug.h"
   8 #include "xmalloc.h"
   9 #include "crc.h"
  10 #include "command.h"
  11
  12 #include "env.h"
  13
  14
  15 #define ENV_SIZE        (CONFIG_ENV_SIZE - sizeof(uint16_t) -1)
  16 #define ACTIVE_FLAG     1
  17 #define OBSOLETE_FLAG   0
  18
  19 #define ENVLIST_DELETE  (1<<0)
  20
  21
  22 /*
  23  * Default Environment
  24  */
  25
  26 #define DELIM           "\0"
  27
  28 const FLASH char default_env[] = {
  29         "bootdelay="    "3"             DELIM
  30         "bootcmd="      "reset; loadf; go ${startaddr}" DELIM
  31         "baudrate="     "115200"        DELIM
  32         "startaddr="    "0"             DELIM
  33         DELIM
  34 };
  35
  36 /* EEPROM storage */
  37 typedef struct environment_s {
  38         uint16_t        crc;            /* CRC16 over data bytes        */
  39         uint8_t         flags;          /* active/obsolete flags        */
  40         char            data[ENV_SIZE]; /* Environment data             */
  41 } env_t;
  42
  43
  44 /* */
  45 typedef struct env_item_s {
  46         char * envvar;
  47 } env_item_t;
  48
  49
  50 static uint8_t env_valid;
  51 static env_item_t env_list[CONFIG_ENVVAR_MAX];
  52 static int entrycount;
  53
  54
  55 static
  56 char env_get_char(uint16_t index)
  57 {
  58         unsigned int off = CONFIG_ENV_OFFSET;
  59         char ret;
  60
  61         switch (env_valid) {
  62         case 2:
  63                 off += CONFIG_ENV_SIZE;
  64         case 1:
  65                 ret = (char) eeprom_read_byte((const uint8_t *)off + index +
  66                                 offsetof(env_t, data));
  67                 break;
  68
  69         default:
  70                 ret = default_env[index];
  71         }
  72
  73         return ret;
  74 }
  75
  76
  77 static
  78 int comp_env_items(const void *m1, const void *m2)
  79 {
  80         env_item_t *ep1 = (env_item_t *) m1;
  81         env_item_t *ep2 = (env_item_t *) m2;
  82
  83         return strcmp(ep1->envvar, ep2->envvar);
  84 }
  85
  86
  87 env_item_t *envlist_search(const MEMX char *name)
  88 {
  89         env_item_t e;
  90
  91         e.envvar = (char *) name;
  92
  93 #ifdef __MEMX
  94         char buf[CONFIG_SYS_ENV_NAMELEN+1];
  95
  96         if (__builtin_avr_flash_segment(name) != -1) {
  97                 char *p = buf;
  98                 while ((*p++ = *name++) != '\0')
  99                         ;
 100                 e.envvar = buf;
 101         }
 102 #endif /* __MEMX */
 103
 104         return bsearch(&e, env_list, entrycount,
 105                                 sizeof(env_item_t), comp_env_items);
 106 }
 107
 108
 109 static
 110 env_item_t *envlist_enter(env_item_t *e)
 111 {
 112         const size_t size = sizeof(env_item_t);
 113         env_item_t *ep;
 114
 115         ep = bsearch(e, env_list, entrycount,
 116                         size, comp_env_items);
 117
 118         if (ep == NULL) {
 119                 if (entrycount < CONFIG_ENVVAR_MAX) {
 120
 121                         env_list[entrycount++] = *e;
 122                         qsort(env_list, entrycount, size, comp_env_items);
 123                         ep = bsearch(e, env_list, entrycount,
 124                                                 size, comp_env_items);
 125                 }
 126         } else {
 127                 free(ep->envvar);
 128                 ep->envvar = e->envvar;
 129         }
 130
 131         return ep;
 132 }
 133
 134
 135 static
 136 int env_item_delete(env_item_t *ep)
 137 {
 138         if (entrycount == 0)
 139                 return -1;
 140
 141         free(ep->envvar);
 142
 143         entrycount--;
 144         size_t size = sizeof(env_item_t);
 145         memmove(ep, ep + 1, (env_list - ep)*size + entrycount*size);
 146
 147         return 0;
 148 }
 149
 150 static
 151 int envlist_delete(const char *name)
 152 {
 153         env_item_t e;
 154
 155         e.envvar = (char *) name;
 156
 157         env_item_t *ep = bsearch(&e, env_list, entrycount,
 158                                 sizeof(env_item_t), comp_env_items);
 159
 160         if (ep != NULL)
 161                 return env_item_delete(ep);
 162
 163         return 1;
 164 }
 165
 166
 167
 168 static
 169 int envlist_import(uint8_t flags)
 170 {
 171         uint16_t index;
 172
 173         int len;
 174         env_item_t e;
 175         char *np, c;
 176         uint_fast8_t ef;
 177
 178         if ((flags & ENVLIST_DELETE) != 0)
 179                 while (entrycount != 0)
 180                         env_item_delete(&env_list[entrycount-1]);
 181
 182         for (index = 0; env_get_char(index) != '\0'; ) {
 183                 for (len = 0; env_get_char(index + len) != '\0'; ++len) {
 184                         if ((index + len) >= ENV_SIZE)
 185                                 return -1;
 186                 }
 187
 188                 np = (char *) xmalloc(len+1);
 189                 if (np == NULL) {
 190                         printf_P(PSTR("## Can't malloc %d bytes\n"), len+1);
 191                         return 1;
 192                 }
 193                 e.envvar = np;
 194                 ef = 0;
 195                 while ((c = env_get_char(index++)) != '\0') {
 196                         if (!ef && (c == '=')) {
 197                                 *np = '\0';
 198                                 ef = 1;
 199                         } else
 200                                 *np = c;
 201                         np++;
 202                 }
 203                 *np = '\0';
 204                 envlist_enter(&e);
 205         }
 206
 207
 208         return 0;
 209 }
 210
 211
 212 static
 213 uint16_t env_crc(uint16_t data_offset)
 214 {
 215         uint16_t crc;
 216         uint16_t i;
 217         char c, c0;
 218
 219         crc = 0xffff;
 220         c = 0xff;
 221         for (i = 0; !(c == 0 && c0 == 0) && i < ENV_SIZE; i++)
 222         {
 223                 c0 = c;
 224                 c = eeprom_read_byte((const uint8_t *) data_offset + i);
 225                 crc = crc16(crc, c);
 226         }
 227         return crc ;
 228 }
 229
 230
 231 /**
 232  * return valid env
 233  */
 234 static
 235 int env_check_valid(void)
 236 {
 237         const uint16_t offset[2] = {CONFIG_ENV_OFFSET,
 238                                     CONFIG_ENV_OFFSET + CONFIG_ENV_SIZE};
 239         uint_fast8_t flags[2], crc_ok[2];
 240         int rc;
 241
 242         /* read FLAGS */
 243         flags[0] = eeprom_read_byte ((uint8_t *) offset[0] +
 244                                 offsetof(env_t, flags));
 245         flags[1] = eeprom_read_byte ((uint8_t *) offset[1] +
 246                                 offsetof(env_t, flags));
 247
 248         /* check CRC */
 249         crc_ok[0] = (
 250                 eeprom_read_word((uint16_t *) offset[0] +
 251                                 offsetof(env_t, crc))
 252                 == env_crc(offset[0] + offsetof(env_t, data))
 253         );
 254         crc_ok[1] = (
 255                 eeprom_read_word((uint16_t *) offset[1] +
 256                                 offsetof(env_t, crc))
 257                 == env_crc(offset[1] + offsetof(env_t, data))
 258         );
 259
 260         if (!crc_ok[0] && !crc_ok[1]) {
 261                 rc = 0;
 262
 263         } else if (crc_ok[0] && !crc_ok[1]) {
 264                 rc = 1;
 265         } else if (!crc_ok[0] && crc_ok[1]) {
 266                 rc = 2;
 267         } else {
 268                 /* both ok - check serial */
 269 #if 1
 270                 if      (flags[1] == ACTIVE_FLAG && flags[0] != ACTIVE_FLAG)
 271                         rc = 2;
 272                 else if (flags[1] == OBSOLETE_FLAG && flags[0] == 0xFF)
 273                         rc = 2;
 274                 else
 275                         rc = 1;
 276 #else
 277                 if (flags[0] == ACTIVE_FLAG && flags[1] == OBSOLETE_FLAG)
 278                         rc = 1;
 279                 else if (flags[0] == OBSOLETE_FLAG && flags[1] == ACTIVE_FLAG)
 280                         rc = 2;
 281                 else if (flags[0] == 0xFF && flags[1] == 0)
 282                         rc = 2;
 283                 else if (flags[1] == 0xFF && flags[0] == 0)
 284                         rc = 1;
 285                 else /* flags are equal - almost impossible */
 286                         rc = 1;
 287 #endif
 288         }
 289
 290         return rc;
 291 }
 292
 293
 294 int env_init(void)
 295 {
 296         env_valid = env_check_valid();
 297         if (env_valid == 0) {
 298                 printf_P(PSTR("*** Warning - bad CRC, "
 299                                 "using default environment\n\n"));
 300         }
 301
 302         envlist_import(ENVLIST_DELETE);
 303         return 0;
 304 }
 305
 306
 307 char *getenv(const MEMX char *name)
 308 {
 309         env_item_t *ep;
 310         char *ret = NULL;
 311
 312         ep = envlist_search(name);
 313         if (ep != NULL)
 314                 ret = ep->envvar + strlen(ep->envvar) +1;
 315         return ret;
 316 }
 317
 318 static
 319 int env_item_save(env_item_t *ep, uint16_t offset, int space_left)
 320 {
 321         int nlen, vlen;
 322         char *var = ep->envvar;
 323
 324         nlen = strlen(var);
 325         if (nlen == 0)
 326                 return 0;
 327         vlen = strlen(var + nlen + 1);
 328         if (vlen == 0)
 329                 return 0;
 330         if (nlen + vlen + 2 > space_left)
 331                 return 0;
 332
 333         eeprom_update_block(var, (uint8_t *) offset, nlen);
 334         offset += nlen;
 335         eeprom_update_byte((uint8_t *) offset++, '=');
 336         eeprom_update_block(var + nlen +1, (uint8_t *) offset, vlen+1);
 337
 338         return nlen + vlen + 2;
 339 }
 340
 341
 342 static
 343 int saveenv(void)
 344 {
 345         unsigned int off     = CONFIG_ENV_OFFSET + CONFIG_ENV_SIZE;
 346         unsigned int off_red = CONFIG_ENV_OFFSET;
 347         unsigned int pos;
 348         int len, left;
 349         uint16_t crc;
 350         int rc = 0;
 351
 352         if (env_valid == 2) {
 353                 off     = CONFIG_ENV_OFFSET;
 354                 off_red = CONFIG_ENV_OFFSET + CONFIG_ENV_SIZE;
 355         }
 356
 357         eeprom_update_byte((uint8_t *) off + offsetof(env_t, flags), 0xff);
 358
 359         pos = off + offsetof(env_t, data);
 360         left = ENV_SIZE - 1;
 361         for (int i = 0 ; i < entrycount; i++) {
 362                 len = env_item_save(&env_list[i], pos, left);
 363                 if (len == 0) {
 364                         return 1;
 365                 }
 366                 pos += len;
 367                 left -= len;
 368         }
 369         /* terminate list */
 370         eeprom_update_byte((uint8_t *) pos, 0);
 371         crc = env_crc(off + offsetof(env_t, data));
 372         eeprom_update_word((uint16_t *) off + offsetof(env_t, crc), crc);
 373         eeprom_update_byte((uint8_t *) off + offsetof(env_t, flags),
 374                                         ACTIVE_FLAG);
 375
 376         if (rc == 0) {
 377                 eeprom_update_byte((uint8_t *) off_red + offsetof(env_t, flags),
 378                                         OBSOLETE_FLAG);
 379                 env_valid = (env_valid == 2) ? 1 : 2;
 380         }
 381
 382         return rc;
 383 }
 384
 385
 386 static
 387 int env_item_print(env_item_t *ep)
 388 {
 389         int len;
 390         char *ev = ep->envvar;
 391
 392         len = printf_P(PSTR("%s="), ev);
 393         len += printf_P(PSTR("%s\n"), ev + len);
 394
 395         return len;
 396 }
 397
 398
 399 /*
 400  * Command interface: print one or all environment variables
 401  *
 402  * Returns -1 in case of error, or length of printed string
 403  */
 404 static
 405 int env_print(const MEMX char *name)
 406 {
 407         int len = -1;
 408
 409         if (name) {             /* print a single name */
 410
 411                 env_item_t *ep = envlist_search(name);
 412                 if (ep != NULL)
 413                         len = env_item_print(ep);
 414
 415         } else {                /* print whole list */
 416                 len = 0;
 417                 for (int i = 0 ; i < entrycount; i++) {
 418                         len += env_item_print(&env_list[i]);
 419                 }
 420         }
 421         return len;
 422 }
 423
 424
 425 /**
 426  * Set or delete environment variable
 427  *
 428  * Set a new environment variable,
 429  * or replace or delete an existing one.
 430  *
 431  * @param flag          (not used)
 432  * @param argc
 433  * @param argv[1]       Environment variable to set or delete
 434  *                      if no more args
 435  * @param argv[2] ...   Value to set it to
 436  *
 437  * @return 0 if ok, 1 on error
 438  */
 439 static
 440 command_ret_t _do_env_set(int flag, int argc, char * const argv[])
 441 {
 442         int i, len;
 443         char *name, *value, *valp, *p;
 444         env_item_t e, *ep;
 445
 446         (void) flag;
 447         debug("Initial value for argc=%d\n", argc);
 448
 449         name = argv[1];
 450         value = argv[2];
 451
 452         if (strchr(name, '=')) {
 453                 printf_P(PSTR("## Error: illegal character '='"
 454                        "in variable name \"%s\"\n"), name);
 455                 return CMD_RET_FAILURE;
 456         }
 457         len = strlen(name);
 458         if (len > CONFIG_SYS_ENV_NAMELEN) {
 459                 printf_P(PSTR("## Error: Variable name \"%s\" too long. "
 460                        "(max %d characters)\n"), name, CONFIG_SYS_ENV_NAMELEN);
 461                 return CMD_RET_FAILURE;
 462         }
 463 /*
 464         env_id++;
 465 */
 466         /* Delete only ? */
 467         if (argc < 3 || argv[2] == NULL) {
 468                 int rc = envlist_delete(name);
 469                 return rc ? CMD_RET_FAILURE : CMD_RET_SUCCESS;
 470         }
 471
 472         /*
 473          * Insert / replace new value
 474          */
 475         for (i = 2, len += 1; i < argc; ++i)
 476                 len += strlen(argv[i]) + 1;
 477
 478         value = xmalloc(len);
 479         if (value == NULL) {
 480                 printf_P(PSTR("## Can't malloc %d bytes\n"), len);
 481                 return CMD_RET_FAILURE;
 482         }
 483         strcpy(value, name);
 484         valp = value + strlen(name) + 1;
 485         for (i = 2, p = valp; i < argc; ++i) {
 486                 char *v = argv[i];
 487
 488                 while ((*p++ = *v++) != '\0')
 489                         ;
 490                 *(p - 1) = ' ';
 491         }
 492         if (p != valp)
 493                 *--p = '\0';
 494
 495         e.envvar = value;
 496         ep = envlist_enter(&e);
 497         if (!ep) {
 498                 printf_P(PSTR("## Error inserting \"%s\" variable.\n"),
 499                         name);
 500                 return CMD_RET_FAILURE;
 501         }
 502
 503         return CMD_RET_SUCCESS;
 504 }
 505
 506 /**
 507  * Set an environment variable
 508  *
 509  * @param varname       Environment variable to set
 510  * @param varvalue      Value to set it to
 511  * @return 0 if ok, 1 on error
 512  */
 513 static
 514 int setenv(const char *varname, const char *varvalue)
 515 {
 516         const char * const argv[3] = { NULL, varname, varvalue };
 517         int argc = 3;
 518
 519         if (varvalue == NULL || varvalue[0] == '\0')
 520                 --argc;
 521
 522         return (int) _do_env_set(0, argc, (char * const *)argv);
 523 }
 524
 525 /**
 526  * Set an environment variable to an integer value
 527  *
 528  * @param name  Environment variable to set
 529  * @param value Value to set it to
 530  * @param radix Base
 531  * @return 0 if ok, 1 on error
 532  */
 533 static
 534 int setenv_intval(const MEMX char *name, unsigned long value, int radix)
 535 {
 536         char buf[11];
 537
 538         ultoa(value, buf, radix);
 539
 540         return setenv(name, buf);
 541 }
 542
 543 /**
 544  * Set an environment variable to a decimal integer value
 545  *
 546  * @param name  Environment variable to set
 547  * @param value Value to set it to
 548  * @return 0 if ok, 1 on error
 549  */
 550 int setenv_ulong(const MEMX char *name, unsigned long value)
 551 {
 552         return setenv_intval(name, value, 10);
 553 }
 554
 555
 556 /**
 557  * Set an environment variable to a value in hex
 558  *
 559  * @param name  Environment variable to set
 560  * @param value Value to set it to
 561  * @return 0 if ok, 1 on error
 562  */
 563 int setenv_hex(const MEMX char *name, unsigned long value)
 564 {
 565         return setenv_intval(name, value, 16);
 566 }
 567
 568
 569 /**
 570  * Decode the integer value of an environment variable and return it.
 571  *
 572  * @param name          Name of environemnt variable
 573  * @param base          Number base to use (normally 10, or 16 for hex)
 574  * @param default_val   Default value to return if the variable is not
 575  *                      found
 576  * @return the decoded value, or default_val if not found
 577  */
 578 unsigned long getenv_ulong(const MEMX char *name, int base, unsigned long default_val)
 579 {
 580         unsigned long value;
 581         char *vp, *endp;
 582
 583         env_item_t *ep = envlist_search(name);
 584
 585         if (ep != NULL ) {
 586                 vp = ep->envvar + strlen(ep->envvar) +1;
 587                 value = strtoul(vp, &endp, base);
 588                 if (endp != vp)
 589                         return value;
 590         }
 591
 592         return default_val;
 593 }
 594
 595
 596 command_ret_t do_env_print(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 597 {
 598         command_ret_t rc = CMD_RET_SUCCESS;
 599
 600         (void) cmdtp; (void) flag;
 601
 602         if (argc == 1) {
 603                 /* print all env vars */
 604                 int size = env_print(NULL);
 605                 if (size < 0)
 606                         return CMD_RET_FAILURE;
 607                 printf_P(PSTR("\nEnvironment size: %d/%d bytes\n"),
 608                         size, ENV_SIZE);
 609                 return CMD_RET_SUCCESS;
 610         }
 611
 612         /* print selected env vars */
 613         for (int i = 1; i < argc; ++i) {
 614                 int rc = env_print(argv[i]);
 615                 if (rc < 0) {
 616                         printf_P(PSTR("## Error: \"%s\" not defined\n"), argv[i]);
 617                         rc = CMD_RET_FAILURE;
 618                 }
 619         }
 620
 621         return rc;
 622 }
 623
 624
 625 command_ret_t do_env_set(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 626 {
 627         (void) cmdtp;
 628
 629         if (argc < 2)
 630                 return CMD_RET_USAGE;
 631
 632         return _do_env_set(flag, argc, argv);
 633 }
 634
 635
 636 command_ret_t do_env_default(cmd_tbl_t *cmdtp, int flag,
 637                           int argc, char * const argv[])
 638 {
 639         (void) cmdtp; (void) flag; (void) argc; (void) argv;
 640
 641         uint8_t tmp = env_valid;
 642         env_valid = 0;
 643
 644         /* Reset the whole environment */
 645         printf_P(PSTR("## Resetting to default environment\n"));
 646         envlist_import(ENVLIST_DELETE);
 647
 648         env_valid = tmp;
 649
 650         return CMD_RET_SUCCESS;
 651 }
 652
 653
 654 command_ret_t do_env_save(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 655 {
 656         (void) cmdtp; (void) flag; (void) argc; (void) argv;
 657
 658         printf_P(PSTR("Saving Environment ...\n"));
 659         return saveenv() ? CMD_RET_FAILURE : CMD_RET_SUCCESS;
 660 }
 661
 662
 663 #if defined(CONFIG_AUTO_COMPLETE)
 664 int env_complete(char *var, int maxv, char *cmdv[], int bufsz, char *buf)
 665 {
 666         ENTRY *match;
 667         int found, idx;
 668
 669         idx = 0;
 670         found = 0;
 671         cmdv[0] = NULL;
 672
 673         while ((idx = hmatch_r(var, idx, &match, &env_htab))) {
 674                 int vallen = strlen(match->key) + 1;
 675
 676                 if (found >= maxv - 2 || bufsz < vallen)
 677                         break;
 678
 679                 cmdv[found++] = buf;
 680                 memcpy(buf, match->key, vallen);
 681                 buf += vallen;
 682                 bufsz -= vallen;
 683         }
 684
 685         qsort(cmdv, found, sizeof(cmdv[0]), strcmp_compar);
 686
 687         if (idx)
 688                 cmdv[found++] = "...";
 689
 690         cmdv[found] = NULL;
 691         return found;
 692 }
 693 #endif