avr/env.c

   1 /*
   2  * (C) Copyright 2014 Leo C. <erbl259-lmu@yahoo.de>
   3  *
   4  * SPDX-License-Identifier:     GPL-2.0+
   5  */
   6
   7 #include "common.h"
   8 #include <string.h>
   9 #include <stdlib.h>
  10 #include <avr/eeprom.h>
  11
  12 #include "config.h"
  13 #include "debug.h"
  14 #include "xmalloc.h"
  15 #include "crc.h"
  16 #include "command.h"
  17 #include "env.h"
  18
  19
  20 #define ENV_SIZE        (CONFIG_ENV_SIZE - sizeof(uint16_t) -1)
  21 #define ACTIVE_FLAG     1
  22 #define OBSOLETE_FLAG   0
  23
  24 #define ENVLIST_DELETE  (1<<0)
  25
  26
  27 /*
  28  * Default Environment
  29  */
  30
  31 #define DELIM           "\0"
  32
  33 const FLASH char default_env[] = {
  34         "bootdelay="    "3"             DELIM
  35         "bootcmd="      "reset; loadf; go ${startaddr}" DELIM
  36         "baudrate="     "115200"        DELIM
  37         "startaddr="    "0"             DELIM
  38         DELIM
  39 };
  40
  41 /* EEPROM storage */
  42 typedef struct environment_s {
  43         uint16_t        crc;            /* CRC16 over data bytes        */
  44         uint8_t         flags;          /* active/obsolete flags        */
  45         char            data[ENV_SIZE]; /* Environment data             */
  46 } env_t;
  47
  48
  49 /* */
  50 typedef struct env_item_s {
  51         char * envvar;
  52 } env_item_t;
  53
  54
  55 static uint8_t env_valid;
  56 static env_item_t env_list[CONFIG_ENVVAR_MAX];
  57 static int entrycount;
  58
  59
  60 static
  61 char env_get_char(uint16_t index)
  62 {
  63         unsigned int off = CONFIG_ENV_OFFSET;
  64         char ret;
  65
  66         switch (env_valid) {
  67         case 2:
  68                 off += CONFIG_ENV_SIZE;
  69         case 1:
  70                 ret = (char) eeprom_read_byte((const uint8_t *)off + index +
  71                                 offsetof(env_t, data));
  72                 break;
  73
  74         default:
  75                 ret = default_env[index];
  76         }
  77
  78         return ret;
  79 }
  80
  81
  82 static const FLASH char *comp_key;
  83
  84 static
  85 int comp_env_items(const void *m1, const void *m2)
  86 {
  87         env_item_t *ep1 = (env_item_t *) m1;
  88         env_item_t *ep2 = (env_item_t *) m2;
  89
  90         if (ep1 == NULL)
  91                 return - strcmp_P(ep2->envvar, comp_key);
  92         else
  93                 return strcmp(ep1->envvar, ep2->envvar);
  94 }
  95
  96
  97 env_item_t *envlist_search(const MEMX char *name)
  98 {
  99 #ifdef __MEMX
 100         if (__builtin_avr_flash_segment(name) != -1) {
 101                 comp_key = name;
 102                 return bsearch(0, env_list, entrycount,
 103                                 sizeof(env_item_t), comp_env_items);
 104         } else {
 105
 106                 env_item_t e;
 107                 e.envvar = (char *) name;
 108
 109                 return bsearch(&e, env_list, entrycount,
 110                                 sizeof(env_item_t), comp_env_items);
 111         }
 112 #else
 113         env_item_t e;
 114         e.envvar = (char *) name;
 115
 116         return bsearch(&e, env_list, entrycount,
 117                                 sizeof(env_item_t), comp_env_items);
 118 #endif /* __MEMX */
 119 }
 120
 121
 122 static
 123 env_item_t *envlist_enter(env_item_t *e)
 124 {
 125         const size_t size = sizeof(env_item_t);
 126         env_item_t *ep;
 127
 128         ep = bsearch(e, env_list, entrycount,
 129                         size, comp_env_items);
 130
 131         if (ep == NULL) {
 132                 if (entrycount < CONFIG_ENVVAR_MAX) {
 133
 134                         env_list[entrycount++] = *e;
 135                         qsort(env_list, entrycount, size, comp_env_items);
 136                         ep = bsearch(e, env_list, entrycount,
 137                                                 size, comp_env_items);
 138                 }
 139         } else {
 140                 free(ep->envvar);
 141                 ep->envvar = e->envvar;
 142         }
 143
 144         return ep;
 145 }
 146
 147
 148 static
 149 int env_item_delete(env_item_t *ep)
 150 {
 151         if (entrycount == 0)
 152                 return -1;
 153
 154         free(ep->envvar);
 155
 156         entrycount--;
 157         size_t size = sizeof(env_item_t);
 158         memmove(ep, ep + 1, (env_list - ep)*size + entrycount*size);
 159
 160         return 0;
 161 }
 162
 163 static
 164 int envlist_delete(const MEMX char *name)
 165 {
 166         env_item_t *ep = envlist_search(name);
 167
 168         if (ep != NULL)
 169                 return env_item_delete(ep);
 170
 171         return 1;
 172 }
 173
 174
 175
 176 static
 177 int envlist_import(uint8_t flags)
 178 {
 179         uint16_t index;
 180
 181         int len;
 182         env_item_t e;
 183         char *np, c;
 184         uint_fast8_t ef;
 185
 186         if ((flags & ENVLIST_DELETE) != 0)
 187                 while (entrycount != 0)
 188                         env_item_delete(&env_list[entrycount-1]);
 189
 190         for (index = 0; env_get_char(index) != '\0'; ) {
 191                 for (len = 0; env_get_char(index + len) != '\0'; ++len) {
 192                         if ((index + len) >= ENV_SIZE)
 193                                 return -1;
 194                 }
 195
 196                 np = (char *) xmalloc(len+1);
 197                 if (np == NULL) {
 198                         printf_P(PSTR("## Can't malloc %d bytes\n"), len+1);
 199                         return 1;
 200                 }
 201                 e.envvar = np;
 202                 ef = 0;
 203                 while ((c = env_get_char(index++)) != '\0') {
 204                         if (!ef && (c == '=')) {
 205                                 *np = '\0';
 206                                 ef = 1;
 207                         } else
 208                                 *np = c;
 209                         np++;
 210                 }
 211                 *np = '\0';
 212                 envlist_enter(&e);
 213         }
 214
 215
 216         return 0;
 217 }
 218
 219
 220 static
 221 uint16_t env_crc(uint16_t data_offset)
 222 {
 223         uint16_t crc;
 224         uint16_t i;
 225         char c, c0;
 226
 227         crc = 0xffff;
 228         c = 0xff;
 229         for (i = 0; !(c == 0 && c0 == 0) && i < ENV_SIZE; i++)
 230         {
 231                 c0 = c;
 232                 c = eeprom_read_byte((const uint8_t *) data_offset + i);
 233                 crc = crc16(crc, c);
 234         }
 235         return crc ;
 236 }
 237
 238
 239 /**
 240  * return valid env
 241  */
 242 static
 243 int env_check_valid(void)
 244 {
 245         const uint16_t offset[2] = {CONFIG_ENV_OFFSET,
 246                                     CONFIG_ENV_OFFSET + CONFIG_ENV_SIZE};
 247         uint_fast8_t flags[2], crc_ok[2];
 248         int rc;
 249
 250         /* read FLAGS */
 251         flags[0] = eeprom_read_byte ((uint8_t *) offset[0] +
 252                                 offsetof(env_t, flags));
 253         flags[1] = eeprom_read_byte ((uint8_t *) offset[1] +
 254                                 offsetof(env_t, flags));
 255
 256         /* check CRC */
 257         crc_ok[0] = (
 258                 eeprom_read_word((uint16_t *) offset[0] +
 259                                 offsetof(env_t, crc))
 260                 == env_crc(offset[0] + offsetof(env_t, data))
 261         );
 262         crc_ok[1] = (
 263                 eeprom_read_word((uint16_t *) offset[1] +
 264                                 offsetof(env_t, crc))
 265                 == env_crc(offset[1] + offsetof(env_t, data))
 266         );
 267
 268         if (!crc_ok[0] && !crc_ok[1]) {
 269                 rc = 0;
 270
 271         } else if (crc_ok[0] && !crc_ok[1]) {
 272                 rc = 1;
 273         } else if (!crc_ok[0] && crc_ok[1]) {
 274                 rc = 2;
 275         } else {
 276                 /* both ok - check serial */
 277 #if 1
 278                 if      (flags[1] == ACTIVE_FLAG && flags[0] != ACTIVE_FLAG)
 279                         rc = 2;
 280                 else if (flags[1] == OBSOLETE_FLAG && flags[0] == 0xFF)
 281                         rc = 2;
 282                 else
 283                         rc = 1;
 284 #else
 285                 if (flags[0] == ACTIVE_FLAG && flags[1] == OBSOLETE_FLAG)
 286                         rc = 1;
 287                 else if (flags[0] == OBSOLETE_FLAG && flags[1] == ACTIVE_FLAG)
 288                         rc = 2;
 289                 else if (flags[0] == 0xFF && flags[1] == 0)
 290                         rc = 2;
 291                 else if (flags[1] == 0xFF && flags[0] == 0)
 292                         rc = 1;
 293                 else /* flags are equal - almost impossible */
 294                         rc = 1;
 295 #endif
 296         }
 297
 298         return rc;
 299 }
 300
 301
 302 int env_init(void)
 303 {
 304         env_valid = env_check_valid();
 305         if (env_valid == 0) {
 306                 printf_P(PSTR("*** Warning - bad CRC, "
 307                                 "using default environment\n\n"));
 308         }
 309
 310         envlist_import(ENVLIST_DELETE);
 311         return 0;
 312 }
 313
 314
 315 char *getenv(const MEMX char *name)
 316 {
 317         env_item_t *ep;
 318         char *ret = NULL;
 319
 320         ep = envlist_search(name);
 321         if (ep != NULL)
 322                 ret = ep->envvar + strlen(ep->envvar) +1;
 323         return ret;
 324 }
 325
 326 static
 327 int env_item_save(env_item_t *ep, uint16_t offset, int space_left)
 328 {
 329         int nlen, vlen;
 330         char *var = ep->envvar;
 331
 332         nlen = strlen(var);
 333         if (nlen == 0)
 334                 return 0;
 335         vlen = strlen(var + nlen + 1);
 336         if (vlen == 0)
 337                 return 0;
 338         if (nlen + vlen + 2 > space_left)
 339                 return 0;
 340
 341         eeprom_update_block(var, (uint8_t *) offset, nlen);
 342         offset += nlen;
 343         eeprom_update_byte((uint8_t *) offset++, '=');
 344         eeprom_update_block(var + nlen +1, (uint8_t *) offset, vlen+1);
 345
 346         return nlen + vlen + 2;
 347 }
 348
 349
 350 static
 351 int saveenv(void)
 352 {
 353         unsigned int off     = CONFIG_ENV_OFFSET + CONFIG_ENV_SIZE;
 354         unsigned int off_red = CONFIG_ENV_OFFSET;
 355         unsigned int pos;
 356         int len, left;
 357         uint16_t crc;
 358         int rc = 0;
 359
 360         if (env_valid == 2) {
 361                 off     = CONFIG_ENV_OFFSET;
 362                 off_red = CONFIG_ENV_OFFSET + CONFIG_ENV_SIZE;
 363         }
 364
 365         eeprom_update_byte((uint8_t *) off + offsetof(env_t, flags), 0xff);
 366
 367         pos = off + offsetof(env_t, data);
 368         left = ENV_SIZE - 1;
 369         for (int i = 0 ; i < entrycount; i++) {
 370                 len = env_item_save(&env_list[i], pos, left);
 371                 if (len == 0) {
 372                         return 1;
 373                 }
 374                 pos += len;
 375                 left -= len;
 376         }
 377         /* terminate list */
 378         eeprom_update_byte((uint8_t *) pos, 0);
 379         crc = env_crc(off + offsetof(env_t, data));
 380         eeprom_update_word((uint16_t *) off + offsetof(env_t, crc), crc);
 381         eeprom_update_byte((uint8_t *) off + offsetof(env_t, flags),
 382                                         ACTIVE_FLAG);
 383
 384         if (rc == 0) {
 385                 eeprom_update_byte((uint8_t *) off_red + offsetof(env_t, flags),
 386                                         OBSOLETE_FLAG);
 387                 env_valid = (env_valid == 2) ? 1 : 2;
 388         }
 389
 390         return rc;
 391 }
 392
 393
 394 static
 395 int env_item_print(env_item_t *ep)
 396 {
 397         int len;
 398         char *ev = ep->envvar;
 399
 400         len = printf_P(PSTR("%s="), ev);
 401         len += printf_P(PSTR("%s\n"), ev + len);
 402
 403         return len;
 404 }
 405
 406
 407 /*
 408  * Command interface: print one or all environment variables
 409  *
 410  * Returns -1 in case of error, or length of printed string
 411  */
 412 static
 413 int env_print(const MEMX char *name)
 414 {
 415         int len = -1;
 416
 417         if (name) {             /* print a single name */
 418
 419                 env_item_t *ep = envlist_search(name);
 420                 if (ep != NULL)
 421                         len = env_item_print(ep);
 422
 423         } else {                /* print whole list */
 424                 len = 0;
 425                 for (int i = 0 ; i < entrycount; i++) {
 426                         len += env_item_print(&env_list[i]);
 427                 }
 428         }
 429         return len;
 430 }
 431
 432
 433 /**
 434  * Set or delete environment variable
 435  *
 436  * Set a new environment variable,
 437  * or replace or delete an existing one.
 438  *
 439  * @param flag          (not used)
 440  * @param argc
 441  * @param argv[1]       Environment variable to set or delete
 442  *                      if no more args
 443  * @param argv[2] ...   Value to set it to
 444  *
 445  * @return 0 if ok, 1 on error
 446  */
 447 static
 448 command_ret_t _do_env_set(int flag, int argc, char * const argv[])
 449 {
 450         int i, len;
 451         char *name, *value, *valp, *p;
 452         env_item_t e, *ep;
 453
 454         (void) flag;
 455         debug("Initial value for argc=%d\n", argc);
 456
 457         name = argv[1];
 458         value = argv[2];
 459
 460         if (strchr(name, '=')) {
 461                 printf_P(PSTR("## Error: illegal character '='"
 462                        "in variable name \"%s\"\n"), name);
 463                 return CMD_RET_FAILURE;
 464         }
 465         len = strlen(name);
 466         if (len > CONFIG_SYS_ENV_NAMELEN) {
 467                 printf_P(PSTR("## Error: Variable name \"%s\" too long. "
 468                        "(max %d characters)\n"), name, CONFIG_SYS_ENV_NAMELEN);
 469                 return CMD_RET_FAILURE;
 470         }
 471 /*
 472         env_id++;
 473 */
 474         /* Delete only ? */
 475         if (argc < 3 || argv[2] == NULL) {
 476                 int rc = envlist_delete(name);
 477                 return rc ? CMD_RET_FAILURE : CMD_RET_SUCCESS;
 478         }
 479
 480         /*
 481          * Insert / replace new value
 482          */
 483         for (i = 2, len += 1; i < argc; ++i)
 484                 len += strlen(argv[i]) + 1;
 485
 486         value = xmalloc(len);
 487         if (value == NULL) {
 488                 printf_P(PSTR("## Can't malloc %d bytes\n"), len);
 489                 return CMD_RET_FAILURE;
 490         }
 491         strcpy(value, name);
 492         valp = value + strlen(name) + 1;
 493         for (i = 2, p = valp; i < argc; ++i) {
 494                 char *v = argv[i];
 495
 496                 while ((*p++ = *v++) != '\0')
 497                         ;
 498                 *(p - 1) = ' ';
 499         }
 500         if (p != valp)
 501                 *--p = '\0';
 502
 503         e.envvar = value;
 504         ep = envlist_enter(&e);
 505         if (!ep) {
 506                 printf_P(PSTR("## Error inserting \"%s\" variable.\n"),
 507                         name);
 508                 return CMD_RET_FAILURE;
 509         }
 510
 511         return CMD_RET_SUCCESS;
 512 }
 513
 514 /**
 515  * Set an environment variable
 516  *
 517  * @param varname       Environment variable to set
 518  * @param varvalue      Value to set it to
 519  * @return 0 if ok, 1 on error
 520  */
 521 static
 522 int setenv(const char *varname, const char *varvalue)
 523 {
 524         const char * const argv[3] = { NULL, varname, varvalue };
 525         int argc = 3;
 526
 527         if (varvalue == NULL || varvalue[0] == '\0')
 528                 --argc;
 529
 530         return (int) _do_env_set(0, argc, (char * const *)argv);
 531 }
 532
 533 /**
 534  * Set an environment variable to an integer value
 535  *
 536  * @param name  Environment variable to set
 537  * @param value Value to set it to
 538  * @param radix Base
 539  * @return 0 if ok, 1 on error
 540  */
 541 static
 542 int setenv_intval(const MEMX char *name, unsigned long value, int radix)
 543 {
 544         char buf[11];
 545
 546         ultoa(value, buf, radix);
 547
 548         return setenv(name, buf);
 549 }
 550
 551 /**
 552  * Set an environment variable to a decimal integer value
 553  *
 554  * @param name  Environment variable to set
 555  * @param value Value to set it to
 556  * @return 0 if ok, 1 on error
 557  */
 558 int setenv_ulong(const MEMX char *name, unsigned long value)
 559 {
 560         return setenv_intval(name, value, 10);
 561 }
 562
 563
 564 /**
 565  * Set an environment variable to a value in hex
 566  *
 567  * @param name  Environment variable to set
 568  * @param value Value to set it to
 569  * @return 0 if ok, 1 on error
 570  */
 571 int setenv_hex(const MEMX char *name, unsigned long value)
 572 {
 573         return setenv_intval(name, value, 16);
 574 }
 575
 576
 577 /**
 578  * Decode the integer value of an environment variable and return it.
 579  *
 580  * @param name          Name of environemnt variable
 581  * @param base          Number base to use (normally 10, or 16 for hex)
 582  * @param default_val   Default value to return if the variable is not
 583  *                      found
 584  * @return the decoded value, or default_val if not found
 585  */
 586 unsigned long getenv_ulong(const MEMX char *name, int base, unsigned long default_val)
 587 {
 588         unsigned long value;
 589         char *vp, *endp;
 590
 591         env_item_t *ep = envlist_search(name);
 592
 593         if (ep != NULL ) {
 594                 vp = ep->envvar + strlen(ep->envvar) +1;
 595                 value = strtoul(vp, &endp, base);
 596                 if (endp != vp)
 597                         return value;
 598         }
 599
 600         return default_val;
 601 }
 602
 603
 604 command_ret_t do_env_print(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 605 {
 606         command_ret_t rc = CMD_RET_SUCCESS;
 607
 608         (void) cmdtp; (void) flag;
 609
 610         if (argc == 1) {
 611                 /* print all env vars */
 612                 int size = env_print(NULL);
 613                 if (size < 0)
 614                         return CMD_RET_FAILURE;
 615                 printf_P(PSTR("\nEnvironment size: %d/%d bytes\n"),
 616                         size, ENV_SIZE);
 617                 return CMD_RET_SUCCESS;
 618         }
 619
 620         /* print selected env vars */
 621         for (int i = 1; i < argc; ++i) {
 622                 int rc = env_print(argv[i]);
 623                 if (rc < 0) {
 624                         printf_P(PSTR("## Error: \"%s\" not defined\n"), argv[i]);
 625                         rc = CMD_RET_FAILURE;
 626                 }
 627         }
 628
 629         return rc;
 630 }
 631
 632
 633 command_ret_t do_env_set(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 634 {
 635         (void) cmdtp;
 636
 637         if (argc < 2)
 638                 return CMD_RET_USAGE;
 639
 640         return _do_env_set(flag, argc, argv);
 641 }
 642
 643
 644 command_ret_t do_env_default(cmd_tbl_t *cmdtp, int flag,
 645                           int argc, char * const argv[])
 646 {
 647         (void) cmdtp; (void) flag; (void) argc; (void) argv;
 648
 649         uint8_t tmp = env_valid;
 650         env_valid = 0;
 651
 652         /* Reset the whole environment */
 653         printf_P(PSTR("## Resetting to default environment\n"));
 654         envlist_import(ENVLIST_DELETE);
 655
 656         env_valid = tmp;
 657
 658         return CMD_RET_SUCCESS;
 659 }
 660
 661
 662 command_ret_t do_env_save(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 663 {
 664         (void) cmdtp; (void) flag; (void) argc; (void) argv;
 665
 666         printf_P(PSTR("Saving Environment ...\n"));
 667         return saveenv() ? CMD_RET_FAILURE : CMD_RET_SUCCESS;
 668 }
 669
 670
 671 #if defined(CONFIG_AUTO_COMPLETE)
 672 int env_complete(char *var, int maxv, char *cmdv[], int bufsz, char *buf)
 673 {
 674         ENTRY *match;
 675         int found, idx;
 676
 677         idx = 0;
 678         found = 0;
 679         cmdv[0] = NULL;
 680
 681         while ((idx = hmatch_r(var, idx, &match, &env_htab))) {
 682                 int vallen = strlen(match->key) + 1;
 683
 684                 if (found >= maxv - 2 || bufsz < vallen)
 685                         break;
 686
 687                 cmdv[found++] = buf;
 688                 memcpy(buf, match->key, vallen);
 689                 buf += vallen;
 690                 bufsz -= vallen;
 691         }
 692
 693         qsort(cmdv, found, sizeof(cmdv[0]), strcmp_compar);
 694
 695         if (idx)
 696                 cmdv[found++] = "...";
 697
 698         cmdv[found] = NULL;
 699         return found;
 700 }
 701 #endif