scripts/kconfig/confdata.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
   4  */
   5
   6 #include <sys/mman.h>
   7 #include <sys/stat.h>
   8 #include <sys/types.h>
   9 #include <ctype.h>
  10 #include <errno.h>
  11 #include <fcntl.h>
  12 #include <limits.h>
  13 #include <stdarg.h>
  14 #include <stdio.h>
  15 #include <stdlib.h>
  16 #include <string.h>
  17 #include <time.h>
  18 #include <unistd.h>
  19
  20 #include "lkc.h"
  21
  22 /* return true if 'path' exists, false otherwise */
  23 static bool is_present(const char *path)
  24 {
  25         struct stat st;
  26
  27         return !stat(path, &st);
  28 }
  29
  30 /* return true if 'path' exists and it is a directory, false otherwise */
  31 static bool is_dir(const char *path)
  32 {
  33         struct stat st;
  34
  35         if (stat(path, &st))
  36                 return false;
  37
  38         return S_ISDIR(st.st_mode);
  39 }
  40
  41 /* return true if the given two files are the same, false otherwise */
  42 static bool is_same(const char *file1, const char *file2)
  43 {
  44         int fd1, fd2;
  45         struct stat st1, st2;
  46         void *map1, *map2;
  47         bool ret = false;
  48
  49         fd1 = open(file1, O_RDONLY);
  50         if (fd1 < 0)
  51                 return ret;
  52
  53         fd2 = open(file2, O_RDONLY);
  54         if (fd2 < 0)
  55                 goto close1;
  56
  57         ret = fstat(fd1, &st1);
  58         if (ret)
  59                 goto close2;
  60         ret = fstat(fd2, &st2);
  61         if (ret)
  62                 goto close2;
  63
  64         if (st1.st_size != st2.st_size)
  65                 goto close2;
  66
  67         map1 = mmap(NULL, st1.st_size, PROT_READ, MAP_PRIVATE, fd1, 0);
  68         if (map1 == MAP_FAILED)
  69                 goto close2;
  70
  71         map2 = mmap(NULL, st2.st_size, PROT_READ, MAP_PRIVATE, fd2, 0);
  72         if (map2 == MAP_FAILED)
  73                 goto close2;
  74
  75         if (bcmp(map1, map2, st1.st_size))
  76                 goto close2;
  77
  78         ret = true;
  79 close2:
  80         close(fd2);
  81 close1:
  82         close(fd1);
  83
  84         return ret;
  85 }
  86
  87 /*
  88  * Create the parent directory of the given path.
  89  *
  90  * For example, if 'include/config/auto.conf' is given, create 'include/config'.
  91  */
  92 static int make_parent_dir(const char *path)
  93 {
  94         char tmp[PATH_MAX + 1];
  95         char *p;
  96
  97         strncpy(tmp, path, sizeof(tmp));
  98         tmp[sizeof(tmp) - 1] = 0;
  99
 100         /* Remove the base name. Just return if nothing is left */
 101         p = strrchr(tmp, '/');
 102         if (!p)
 103                 return 0;
 104         *(p + 1) = 0;
 105
 106         /* Just in case it is an absolute path */
 107         p = tmp;
 108         while (*p == '/')
 109                 p++;
 110
 111         while ((p = strchr(p, '/'))) {
 112                 *p = 0;
 113
 114                 /* skip if the directory exists */
 115                 if (!is_dir(tmp) && mkdir(tmp, 0755))
 116                         return -1;
 117
 118                 *p = '/';
 119                 while (*p == '/')
 120                         p++;
 121         }
 122
 123         return 0;
 124 }
 125
 126 static char depfile_path[PATH_MAX];
 127 static size_t depfile_prefix_len;
 128
 129 /* touch depfile for symbol 'name' */
 130 static int conf_touch_dep(const char *name)
 131 {
 132         int fd, ret;
 133         char *d;
 134
 135         /* check overflow: prefix + name + '\0' must fit in buffer. */
 136         if (depfile_prefix_len + strlen(name) + 1 > sizeof(depfile_path))
 137                 return -1;
 138
 139         d = depfile_path + depfile_prefix_len;
 140         strcpy(d, name);
 141
 142         /* Assume directory path already exists. */
 143         fd = open(depfile_path, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 144         if (fd == -1) {
 145                 if (errno != ENOENT)
 146                         return -1;
 147
 148                 ret = make_parent_dir(depfile_path);
 149                 if (ret)
 150                         return ret;
 151
 152                 /* Try it again. */
 153                 fd = open(depfile_path, O_WRONLY | O_CREAT | O_TRUNC, 0644);
 154                 if (fd == -1)
 155                         return -1;
 156         }
 157         close(fd);
 158
 159         return 0;
 160 }
 161
 162 struct conf_printer {
 163         void (*print_symbol)(FILE *, struct symbol *, const char *, void *);
 164         void (*print_comment)(FILE *, const char *, void *);
 165 };
 166
 167 static void conf_warning(const char *fmt, ...)
 168         __attribute__ ((format (printf, 1, 2)));
 169
 170 static void conf_message(const char *fmt, ...)
 171         __attribute__ ((format (printf, 1, 2)));
 172
 173 static const char *conf_filename;
 174 static int conf_lineno, conf_warnings;
 175
 176 static void conf_warning(const char *fmt, ...)
 177 {
 178         va_list ap;
 179         va_start(ap, fmt);
 180         fprintf(stderr, "%s:%d:warning: ", conf_filename, conf_lineno);
 181         vfprintf(stderr, fmt, ap);
 182         fprintf(stderr, "\n");
 183         va_end(ap);
 184         conf_warnings++;
 185 }
 186
 187 static void conf_default_message_callback(const char *s)
 188 {
 189         printf("#\n# ");
 190         printf("%s", s);
 191         printf("\n#\n");
 192 }
 193
 194 static void (*conf_message_callback)(const char *s) =
 195         conf_default_message_callback;
 196 void conf_set_message_callback(void (*fn)(const char *s))
 197 {
 198         conf_message_callback = fn;
 199 }
 200
 201 static void conf_message(const char *fmt, ...)
 202 {
 203         va_list ap;
 204         char buf[4096];
 205
 206         if (!conf_message_callback)
 207                 return;
 208
 209         va_start(ap, fmt);
 210
 211         vsnprintf(buf, sizeof(buf), fmt, ap);
 212         conf_message_callback(buf);
 213         va_end(ap);
 214 }
 215
 216 const char *conf_get_configname(void)
 217 {
 218         char *name = getenv("KCONFIG_CONFIG");
 219
 220         return name ? name : ".config";
 221 }
 222
 223 static const char *conf_get_autoconfig_name(void)
 224 {
 225         char *name = getenv("KCONFIG_AUTOCONFIG");
 226
 227         return name ? name : "include/config/auto.conf";
 228 }
 229
 230 static int conf_set_sym_val(struct symbol *sym, int def, int def_flags, char *p)
 231 {
 232         char *p2;
 233
 234         switch (sym->type) {
 235         case S_TRISTATE:
 236                 if (p[0] == 'm') {
 237                         sym->def[def].tri = mod;
 238                         sym->flags |= def_flags;
 239                         break;
 240                 }
 241                 /* fall through */
 242         case S_BOOLEAN:
 243                 if (p[0] == 'y') {
 244                         sym->def[def].tri = yes;
 245                         sym->flags |= def_flags;
 246                         break;
 247                 }
 248                 if (p[0] == 'n') {
 249                         sym->def[def].tri = no;
 250                         sym->flags |= def_flags;
 251                         break;
 252                 }
 253                 if (def != S_DEF_AUTO)
 254                         conf_warning("symbol value '%s' invalid for %s",
 255                                      p, sym->name);
 256                 return 1;
 257         case S_STRING:
 258                 if (*p++ != '"')
 259                         break;
 260                 for (p2 = p; (p2 = strpbrk(p2, "\"\\")); p2++) {
 261                         if (*p2 == '"') {
 262                                 *p2 = 0;
 263                                 break;
 264                         }
 265                         memmove(p2, p2 + 1, strlen(p2));
 266                 }
 267                 if (!p2) {
 268                         if (def != S_DEF_AUTO)
 269                                 conf_warning("invalid string found");
 270                         return 1;
 271                 }
 272                 /* fall through */
 273         case S_INT:
 274         case S_HEX:
 275                 if (sym_string_valid(sym, p)) {
 276                         sym->def[def].val = xstrdup(p);
 277                         sym->flags |= def_flags;
 278                 } else {
 279                         if (def != S_DEF_AUTO)
 280                                 conf_warning("symbol value '%s' invalid for %s",
 281                                              p, sym->name);
 282                         return 1;
 283                 }
 284                 break;
 285         default:
 286                 ;
 287         }
 288         return 0;
 289 }
 290
 291 #define LINE_GROWTH 16
 292 static int add_byte(int c, char **lineptr, size_t slen, size_t *n)
 293 {
 294         char *nline;
 295         size_t new_size = slen + 1;
 296         if (new_size > *n) {
 297                 new_size += LINE_GROWTH - 1;
 298                 new_size *= 2;
 299                 nline = xrealloc(*lineptr, new_size);
 300                 if (!nline)
 301                         return -1;
 302
 303                 *lineptr = nline;
 304                 *n = new_size;
 305         }
 306
 307         (*lineptr)[slen] = c;
 308
 309         return 0;
 310 }
 311
 312 static ssize_t compat_getline(char **lineptr, size_t *n, FILE *stream)
 313 {
 314         char *line = *lineptr;
 315         size_t slen = 0;
 316
 317         for (;;) {
 318                 int c = getc(stream);
 319
 320                 switch (c) {
 321                 case '\n':
 322                         if (add_byte(c, &line, slen, n) < 0)
 323                                 goto e_out;
 324                         slen++;
 325                         /* fall through */
 326                 case EOF:
 327                         if (add_byte('\0', &line, slen, n) < 0)
 328                                 goto e_out;
 329                         *lineptr = line;
 330                         if (slen == 0)
 331                                 return -1;
 332                         return slen;
 333                 default:
 334                         if (add_byte(c, &line, slen, n) < 0)
 335                                 goto e_out;
 336                         slen++;
 337                 }
 338         }
 339
 340 e_out:
 341         line[slen-1] = '\0';
 342         *lineptr = line;
 343         return -1;
 344 }
 345
 346 int conf_read_simple(const char *name, int def)
 347 {
 348         FILE *in = NULL;
 349         char   *line = NULL;
 350         size_t  line_asize = 0;
 351         char *p, *p2;
 352         struct symbol *sym;
 353         int i, def_flags;
 354
 355         if (name) {
 356                 in = zconf_fopen(name);
 357         } else {
 358                 char *env;
 359
 360                 name = conf_get_configname();
 361                 in = zconf_fopen(name);
 362                 if (in)
 363                         goto load;
 364                 conf_set_changed(true);
 365
 366                 env = getenv("KCONFIG_DEFCONFIG_LIST");
 367                 if (!env)
 368                         return 1;
 369
 370                 while (1) {
 371                         bool is_last;
 372
 373                         while (isspace(*env))
 374                                 env++;
 375
 376                         if (!*env)
 377                                 break;
 378
 379                         p = env;
 380                         while (*p && !isspace(*p))
 381                                 p++;
 382
 383                         is_last = (*p == '\0');
 384
 385                         *p = '\0';
 386
 387                         in = zconf_fopen(env);
 388                         if (in) {
 389                                 conf_message("using defaults found in %s",
 390                                              env);
 391                                 goto load;
 392                         }
 393
 394                         if (is_last)
 395                                 break;
 396
 397                         env = p + 1;
 398                 }
 399         }
 400         if (!in)
 401                 return 1;
 402
 403 load:
 404         conf_filename = name;
 405         conf_lineno = 0;
 406         conf_warnings = 0;
 407
 408         def_flags = SYMBOL_DEF << def;
 409         for_all_symbols(i, sym) {
 410                 sym->flags |= SYMBOL_CHANGED;
 411                 sym->flags &= ~(def_flags|SYMBOL_VALID);
 412                 if (sym_is_choice(sym))
 413                         sym->flags |= def_flags;
 414                 switch (sym->type) {
 415                 case S_INT:
 416                 case S_HEX:
 417                 case S_STRING:
 418                         if (sym->def[def].val)
 419                                 free(sym->def[def].val);
 420                         /* fall through */
 421                 default:
 422                         sym->def[def].val = NULL;
 423                         sym->def[def].tri = no;
 424                 }
 425         }
 426
 427         while (compat_getline(&line, &line_asize, in) != -1) {
 428                 conf_lineno++;
 429                 sym = NULL;
 430                 if (line[0] == '#') {
 431                         if (memcmp(line + 2, CONFIG_, strlen(CONFIG_)))
 432                                 continue;
 433                         p = strchr(line + 2 + strlen(CONFIG_), ' ');
 434                         if (!p)
 435                                 continue;
 436                         *p++ = 0;
 437                         if (strncmp(p, "is not set", 10))
 438                                 continue;
 439                         if (def == S_DEF_USER) {
 440                                 sym = sym_find(line + 2 + strlen(CONFIG_));
 441                                 if (!sym) {
 442                                         conf_set_changed(true);
 443                                         continue;
 444                                 }
 445                         } else {
 446                                 sym = sym_lookup(line + 2 + strlen(CONFIG_), 0);
 447                                 if (sym->type == S_UNKNOWN)
 448                                         sym->type = S_BOOLEAN;
 449                         }
 450                         if (sym->flags & def_flags) {
 451                                 conf_warning("override: reassigning to symbol %s", sym->name);
 452                         }
 453                         switch (sym->type) {
 454                         case S_BOOLEAN:
 455                         case S_TRISTATE:
 456                                 sym->def[def].tri = no;
 457                                 sym->flags |= def_flags;
 458                                 break;
 459                         default:
 460                                 ;
 461                         }
 462                 } else if (memcmp(line, CONFIG_, strlen(CONFIG_)) == 0) {
 463                         p = strchr(line + strlen(CONFIG_), '=');
 464                         if (!p)
 465                                 continue;
 466                         *p++ = 0;
 467                         p2 = strchr(p, '\n');
 468                         if (p2) {
 469                                 *p2-- = 0;
 470                                 if (*p2 == '\r')
 471                                         *p2 = 0;
 472                         }
 473
 474                         sym = sym_find(line + strlen(CONFIG_));
 475                         if (!sym) {
 476                                 if (def == S_DEF_AUTO)
 477                                         /*
 478                                          * Reading from include/config/auto.conf
 479                                          * If CONFIG_FOO previously existed in
 480                                          * auto.conf but it is missing now,
 481                                          * include/config/FOO must be touched.
 482                                          */
 483                                         conf_touch_dep(line + strlen(CONFIG_));
 484                                 else
 485                                         conf_set_changed(true);
 486                                 continue;
 487                         }
 488
 489                         if (sym->flags & def_flags) {
 490                                 conf_warning("override: reassigning to symbol %s", sym->name);
 491                         }
 492                         if (conf_set_sym_val(sym, def, def_flags, p))
 493                                 continue;
 494                 } else {
 495                         if (line[0] != '\r' && line[0] != '\n')
 496                                 conf_warning("unexpected data: %.*s",
 497                                              (int)strcspn(line, "\r\n"), line);
 498
 499                         continue;
 500                 }
 501
 502                 if (sym && sym_is_choice_value(sym)) {
 503                         struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
 504                         switch (sym->def[def].tri) {
 505                         case no:
 506                                 break;
 507                         case mod:
 508                                 if (cs->def[def].tri == yes) {
 509                                         conf_warning("%s creates inconsistent choice state", sym->name);
 510                                         cs->flags &= ~def_flags;
 511                                 }
 512                                 break;
 513                         case yes:
 514                                 if (cs->def[def].tri != no)
 515                                         conf_warning("override: %s changes choice state", sym->name);
 516                                 cs->def[def].val = sym;
 517                                 break;
 518                         }
 519                         cs->def[def].tri = EXPR_OR(cs->def[def].tri, sym->def[def].tri);
 520                 }
 521         }
 522         free(line);
 523         fclose(in);
 524         return 0;
 525 }
 526
 527 int conf_read(const char *name)
 528 {
 529         struct symbol *sym;
 530         int conf_unsaved = 0;
 531         int i;
 532
 533         conf_set_changed(false);
 534
 535         if (conf_read_simple(name, S_DEF_USER)) {
 536                 sym_calc_value(modules_sym);
 537                 return 1;
 538         }
 539
 540         sym_calc_value(modules_sym);
 541
 542         for_all_symbols(i, sym) {
 543                 sym_calc_value(sym);
 544                 if (sym_is_choice(sym) || (sym->flags & SYMBOL_NO_WRITE))
 545                         continue;
 546                 if (sym_has_value(sym) && (sym->flags & SYMBOL_WRITE)) {
 547                         /* check that calculated value agrees with saved value */
 548                         switch (sym->type) {
 549                         case S_BOOLEAN:
 550                         case S_TRISTATE:
 551                                 if (sym->def[S_DEF_USER].tri == sym_get_tristate_value(sym))
 552                                         continue;
 553                                 break;
 554                         default:
 555                                 if (!strcmp(sym->curr.val, sym->def[S_DEF_USER].val))
 556                                         continue;
 557                                 break;
 558                         }
 559                 } else if (!sym_has_value(sym) && !(sym->flags & SYMBOL_WRITE))
 560                         /* no previous value and not saved */
 561                         continue;
 562                 conf_unsaved++;
 563                 /* maybe print value in verbose mode... */
 564         }
 565
 566         for_all_symbols(i, sym) {
 567                 if (sym_has_value(sym) && !sym_is_choice_value(sym)) {
 568                         /* Reset values of generates values, so they'll appear
 569                          * as new, if they should become visible, but that
 570                          * doesn't quite work if the Kconfig and the saved
 571                          * configuration disagree.
 572                          */
 573                         if (sym->visible == no && !conf_unsaved)
 574                                 sym->flags &= ~SYMBOL_DEF_USER;
 575                         switch (sym->type) {
 576                         case S_STRING:
 577                         case S_INT:
 578                         case S_HEX:
 579                                 /* Reset a string value if it's out of range */
 580                                 if (sym_string_within_range(sym, sym->def[S_DEF_USER].val))
 581                                         break;
 582                                 sym->flags &= ~(SYMBOL_VALID|SYMBOL_DEF_USER);
 583                                 conf_unsaved++;
 584                                 break;
 585                         default:
 586                                 break;
 587                         }
 588                 }
 589         }
 590
 591         if (conf_warnings || conf_unsaved)
 592                 conf_set_changed(true);
 593
 594         return 0;
 595 }
 596
 597 /*
 598  * Kconfig configuration printer
 599  *
 600  * This printer is used when generating the resulting configuration after
 601  * kconfig invocation and `defconfig' files. Unset symbol might be omitted by
 602  * passing a non-NULL argument to the printer.
 603  *
 604  */
 605 static void
 606 kconfig_print_symbol(FILE *fp, struct symbol *sym, const char *value, void *arg)
 607 {
 608
 609         switch (sym->type) {
 610         case S_BOOLEAN:
 611         case S_TRISTATE:
 612                 if (*value == 'n') {
 613                         bool skip_unset = (arg != NULL);
 614
 615                         if (!skip_unset)
 616                                 fprintf(fp, "# %s%s is not set\n",
 617                                     CONFIG_, sym->name);
 618                         return;
 619                 }
 620                 break;
 621         default:
 622                 break;
 623         }
 624
 625         fprintf(fp, "%s%s=%s\n", CONFIG_, sym->name, value);
 626 }
 627
 628 static void
 629 kconfig_print_comment(FILE *fp, const char *value, void *arg)
 630 {
 631         const char *p = value;
 632         size_t l;
 633
 634         for (;;) {
 635                 l = strcspn(p, "\n");
 636                 fprintf(fp, "#");
 637                 if (l) {
 638                         fprintf(fp, " ");
 639                         xfwrite(p, l, 1, fp);
 640                         p += l;
 641                 }
 642                 fprintf(fp, "\n");
 643                 if (*p++ == '\0')
 644                         break;
 645         }
 646 }
 647
 648 static struct conf_printer kconfig_printer_cb =
 649 {
 650         .print_symbol = kconfig_print_symbol,
 651         .print_comment = kconfig_print_comment,
 652 };
 653
 654 /*
 655  * Header printer
 656  *
 657  * This printer is used when generating the `include/generated/autoconf.h' file.
 658  */
 659 static void
 660 header_print_symbol(FILE *fp, struct symbol *sym, const char *value, void *arg)
 661 {
 662
 663         switch (sym->type) {
 664         case S_BOOLEAN:
 665         case S_TRISTATE: {
 666                 const char *suffix = "";
 667
 668                 switch (*value) {
 669                 case 'n':
 670                         break;
 671                 case 'm':
 672                         suffix = "_MODULE";
 673                         /* fall through */
 674                 default:
 675                         fprintf(fp, "#define %s%s%s 1\n",
 676                             CONFIG_, sym->name, suffix);
 677                 }
 678                 break;
 679         }
 680         case S_HEX: {
 681                 const char *prefix = "";
 682
 683                 if (value[0] != '0' || (value[1] != 'x' && value[1] != 'X'))
 684                         prefix = "0x";
 685                 fprintf(fp, "#define %s%s %s%s\n",
 686                     CONFIG_, sym->name, prefix, value);
 687                 break;
 688         }
 689         case S_STRING:
 690         case S_INT:
 691                 fprintf(fp, "#define %s%s %s\n",
 692                     CONFIG_, sym->name, value);
 693                 break;
 694         default:
 695                 break;
 696         }
 697
 698 }
 699
 700 static void
 701 header_print_comment(FILE *fp, const char *value, void *arg)
 702 {
 703         const char *p = value;
 704         size_t l;
 705
 706         fprintf(fp, "/*\n");
 707         for (;;) {
 708                 l = strcspn(p, "\n");
 709                 fprintf(fp, " *");
 710                 if (l) {
 711                         fprintf(fp, " ");
 712                         xfwrite(p, l, 1, fp);
 713                         p += l;
 714                 }
 715                 fprintf(fp, "\n");
 716                 if (*p++ == '\0')
 717                         break;
 718         }
 719         fprintf(fp, " */\n");
 720 }
 721
 722 static struct conf_printer header_printer_cb =
 723 {
 724         .print_symbol = header_print_symbol,
 725         .print_comment = header_print_comment,
 726 };
 727
 728 static void conf_write_symbol(FILE *fp, struct symbol *sym,
 729                               struct conf_printer *printer, void *printer_arg)
 730 {
 731         const char *str;
 732
 733         switch (sym->type) {
 734         case S_UNKNOWN:
 735                 break;
 736         case S_STRING:
 737                 str = sym_get_string_value(sym);
 738                 str = sym_escape_string_value(str);
 739                 printer->print_symbol(fp, sym, str, printer_arg);
 740                 free((void *)str);
 741                 break;
 742         default:
 743                 str = sym_get_string_value(sym);
 744                 printer->print_symbol(fp, sym, str, printer_arg);
 745         }
 746 }
 747
 748 static void
 749 conf_write_heading(FILE *fp, struct conf_printer *printer, void *printer_arg)
 750 {
 751         char buf[256];
 752
 753         snprintf(buf, sizeof(buf),
 754             "\n"
 755             "Automatically generated file; DO NOT EDIT.\n"
 756             "%s\n",
 757             rootmenu.prompt->text);
 758
 759         printer->print_comment(fp, buf, printer_arg);
 760 }
 761
 762 /*
 763  * Write out a minimal config.
 764  * All values that has default values are skipped as this is redundant.
 765  */
 766 int conf_write_defconfig(const char *filename)
 767 {
 768         struct symbol *sym;
 769         struct menu *menu;
 770         FILE *out;
 771
 772         out = fopen(filename, "w");
 773         if (!out)
 774                 return 1;
 775
 776         sym_clear_all_valid();
 777
 778         /* Traverse all menus to find all relevant symbols */
 779         menu = rootmenu.list;
 780
 781         while (menu != NULL)
 782         {
 783                 sym = menu->sym;
 784                 if (sym == NULL) {
 785                         if (!menu_is_visible(menu))
 786                                 goto next_menu;
 787                 } else if (!sym_is_choice(sym)) {
 788                         sym_calc_value(sym);
 789                         if (!(sym->flags & SYMBOL_WRITE))
 790                                 goto next_menu;
 791                         sym->flags &= ~SYMBOL_WRITE;
 792                         /* If we cannot change the symbol - skip */
 793                         if (!sym_is_changeable(sym))
 794                                 goto next_menu;
 795                         /* If symbol equals to default value - skip */
 796                         if (strcmp(sym_get_string_value(sym), sym_get_string_default(sym)) == 0)
 797                                 goto next_menu;
 798
 799                         /*
 800                          * If symbol is a choice value and equals to the
 801                          * default for a choice - skip.
 802                          * But only if value is bool and equal to "y" and
 803                          * choice is not "optional".
 804                          * (If choice is "optional" then all values can be "n")
 805                          */
 806                         if (sym_is_choice_value(sym)) {
 807                                 struct symbol *cs;
 808                                 struct symbol *ds;
 809
 810                                 cs = prop_get_symbol(sym_get_choice_prop(sym));
 811                                 ds = sym_choice_default(cs);
 812                                 if (!sym_is_optional(cs) && sym == ds) {
 813                                         if ((sym->type == S_BOOLEAN) &&
 814                                             sym_get_tristate_value(sym) == yes)
 815                                                 goto next_menu;
 816                                 }
 817                         }
 818                         conf_write_symbol(out, sym, &kconfig_printer_cb, NULL);
 819                 }
 820 next_menu:
 821                 if (menu->list != NULL) {
 822                         menu = menu->list;
 823                 }
 824                 else if (menu->next != NULL) {
 825                         menu = menu->next;
 826                 } else {
 827                         while ((menu = menu->parent)) {
 828                                 if (menu->next != NULL) {
 829                                         menu = menu->next;
 830                                         break;
 831                                 }
 832                         }
 833                 }
 834         }
 835         fclose(out);
 836         return 0;
 837 }
 838
 839 int conf_write(const char *name)
 840 {
 841         FILE *out;
 842         struct symbol *sym;
 843         struct menu *menu;
 844         const char *str;
 845         char tmpname[PATH_MAX + 1], oldname[PATH_MAX + 1];
 846         char *env;
 847         int i;
 848         bool need_newline = false;
 849
 850         if (!name)
 851                 name = conf_get_configname();
 852
 853         if (!*name) {
 854                 fprintf(stderr, "config name is empty\n");
 855                 return -1;
 856         }
 857
 858         if (is_dir(name)) {
 859                 fprintf(stderr, "%s: Is a directory\n", name);
 860                 return -1;
 861         }
 862
 863         if (make_parent_dir(name))
 864                 return -1;
 865
 866         env = getenv("KCONFIG_OVERWRITECONFIG");
 867         if (env && *env) {
 868                 *tmpname = 0;
 869                 out = fopen(name, "w");
 870         } else {
 871                 snprintf(tmpname, sizeof(tmpname), "%s.%d.tmp",
 872                          name, (int)getpid());
 873                 out = fopen(tmpname, "w");
 874         }
 875         if (!out)
 876                 return 1;
 877
 878         conf_write_heading(out, &kconfig_printer_cb, NULL);
 879
 880         if (!conf_get_changed())
 881                 sym_clear_all_valid();
 882
 883         menu = rootmenu.list;
 884         while (menu) {
 885                 sym = menu->sym;
 886                 if (!sym) {
 887                         if (!menu_is_visible(menu))
 888                                 goto next;
 889                         str = menu_get_prompt(menu);
 890                         fprintf(out, "\n"
 891                                      "#\n"
 892                                      "# %s\n"
 893                                      "#\n", str);
 894                         need_newline = false;
 895                 } else if (!(sym->flags & SYMBOL_CHOICE) &&
 896                            !(sym->flags & SYMBOL_WRITTEN)) {
 897                         sym_calc_value(sym);
 898                         if (!(sym->flags & SYMBOL_WRITE))
 899                                 goto next;
 900                         if (need_newline) {
 901                                 fprintf(out, "\n");
 902                                 need_newline = false;
 903                         }
 904                         sym->flags |= SYMBOL_WRITTEN;
 905                         conf_write_symbol(out, sym, &kconfig_printer_cb, NULL);
 906                 }
 907
 908 next:
 909                 if (menu->list) {
 910                         menu = menu->list;
 911                         continue;
 912                 }
 913                 if (menu->next)
 914                         menu = menu->next;
 915                 else while ((menu = menu->parent)) {
 916                         if (!menu->sym && menu_is_visible(menu) &&
 917                             menu != &rootmenu) {
 918                                 str = menu_get_prompt(menu);
 919                                 fprintf(out, "# end of %s\n", str);
 920                                 need_newline = true;
 921                         }
 922                         if (menu->next) {
 923                                 menu = menu->next;
 924                                 break;
 925                         }
 926                 }
 927         }
 928         fclose(out);
 929
 930         for_all_symbols(i, sym)
 931                 sym->flags &= ~SYMBOL_WRITTEN;
 932
 933         if (*tmpname) {
 934                 if (is_same(name, tmpname)) {
 935                         conf_message("No change to %s", name);
 936                         unlink(tmpname);
 937                         conf_set_changed(false);
 938                         return 0;
 939                 }
 940
 941                 snprintf(oldname, sizeof(oldname), "%s.old", name);
 942                 rename(name, oldname);
 943                 if (rename(tmpname, name))
 944                         return 1;
 945         }
 946
 947         conf_message("configuration written to %s", name);
 948
 949         conf_set_changed(false);
 950
 951         return 0;
 952 }
 953
 954 /* write a dependency file as used by kbuild to track dependencies */
 955 static int conf_write_dep(const char *name)
 956 {
 957         struct file *file;
 958         FILE *out;
 959
 960         out = fopen("..config.tmp", "w");
 961         if (!out)
 962                 return 1;
 963         fprintf(out, "deps_config := \\\n");
 964         for (file = file_list; file; file = file->next) {
 965                 if (file->next)
 966                         fprintf(out, "\t%s \\\n", file->name);
 967                 else
 968                         fprintf(out, "\t%s\n", file->name);
 969         }
 970         fprintf(out, "\n%s: \\\n"
 971                      "\t$(deps_config)\n\n", conf_get_autoconfig_name());
 972
 973         env_write_dep(out, conf_get_autoconfig_name());
 974
 975         fprintf(out, "\n$(deps_config): ;\n");
 976         fclose(out);
 977
 978         if (make_parent_dir(name))
 979                 return 1;
 980         rename("..config.tmp", name);
 981         return 0;
 982 }
 983
 984 static int conf_touch_deps(void)
 985 {
 986         const char *name;
 987         struct symbol *sym;
 988         int res, i;
 989
 990         strcpy(depfile_path, "include/config/");
 991         depfile_prefix_len = strlen(depfile_path);
 992
 993         name = conf_get_autoconfig_name();
 994         conf_read_simple(name, S_DEF_AUTO);
 995         sym_calc_value(modules_sym);
 996
 997         for_all_symbols(i, sym) {
 998                 sym_calc_value(sym);
 999                 if ((sym->flags & SYMBOL_NO_WRITE) || !sym->name)
1000                         continue;
1001                 if (sym->flags & SYMBOL_WRITE) {
1002                         if (sym->flags & SYMBOL_DEF_AUTO) {
1003                                 /*
1004                                  * symbol has old and new value,
1005                                  * so compare them...
1006                                  */
1007                                 switch (sym->type) {
1008                                 case S_BOOLEAN:
1009                                 case S_TRISTATE:
1010                                         if (sym_get_tristate_value(sym) ==
1011                                             sym->def[S_DEF_AUTO].tri)
1012                                                 continue;
1013                                         break;
1014                                 case S_STRING:
1015                                 case S_HEX:
1016                                 case S_INT:
1017                                         if (!strcmp(sym_get_string_value(sym),
1018                                                     sym->def[S_DEF_AUTO].val))
1019                                                 continue;
1020                                         break;
1021                                 default:
1022                                         break;
1023                                 }
1024                         } else {
1025                                 /*
1026                                  * If there is no old value, only 'no' (unset)
1027                                  * is allowed as new value.
1028                                  */
1029                                 switch (sym->type) {
1030                                 case S_BOOLEAN:
1031                                 case S_TRISTATE:
1032                                         if (sym_get_tristate_value(sym) == no)
1033                                                 continue;
1034                                         break;
1035                                 default:
1036                                         break;
1037                                 }
1038                         }
1039                 } else if (!(sym->flags & SYMBOL_DEF_AUTO))
1040                         /* There is neither an old nor a new value. */
1041                         continue;
1042                 /* else
1043                  *      There is an old value, but no new value ('no' (unset)
1044                  *      isn't saved in auto.conf, so the old value is always
1045                  *      different from 'no').
1046                  */
1047
1048                 res = conf_touch_dep(sym->name);
1049                 if (res)
1050                         return res;
1051         }
1052
1053         return 0;
1054 }
1055
1056 int conf_write_autoconf(int overwrite)
1057 {
1058         struct symbol *sym;
1059         const char *name;
1060         const char *autoconf_name = conf_get_autoconfig_name();
1061         FILE *out, *out_h;
1062         int i;
1063
1064         if (!overwrite && is_present(autoconf_name))
1065                 return 0;
1066
1067         conf_write_dep("include/config/auto.conf.cmd");
1068
1069         if (conf_touch_deps())
1070                 return 1;
1071
1072         out = fopen(".tmpconfig", "w");
1073         if (!out)
1074                 return 1;
1075
1076         out_h = fopen(".tmpconfig.h", "w");
1077         if (!out_h) {
1078                 fclose(out);
1079                 return 1;
1080         }
1081
1082         conf_write_heading(out, &kconfig_printer_cb, NULL);
1083         conf_write_heading(out_h, &header_printer_cb, NULL);
1084
1085         for_all_symbols(i, sym) {
1086                 sym_calc_value(sym);
1087                 if (!(sym->flags & SYMBOL_WRITE) || !sym->name)
1088                         continue;
1089
1090                 /* write symbols to auto.conf and autoconf.h */
1091                 conf_write_symbol(out, sym, &kconfig_printer_cb, (void *)1);
1092                 conf_write_symbol(out_h, sym, &header_printer_cb, NULL);
1093         }
1094         fclose(out);
1095         fclose(out_h);
1096
1097         name = getenv("KCONFIG_AUTOHEADER");
1098         if (!name)
1099                 name = "include/generated/autoconf.h";
1100         if (make_parent_dir(name))
1101                 return 1;
1102         if (rename(".tmpconfig.h", name))
1103                 return 1;
1104
1105         if (make_parent_dir(autoconf_name))
1106                 return 1;
1107         /*
1108          * This must be the last step, kbuild has a dependency on auto.conf
1109          * and this marks the successful completion of the previous steps.
1110          */
1111         if (rename(".tmpconfig", autoconf_name))
1112                 return 1;
1113
1114         return 0;
1115 }
1116
1117 static bool conf_changed;
1118 static void (*conf_changed_callback)(void);
1119
1120 void conf_set_changed(bool val)
1121 {
1122         if (conf_changed_callback && conf_changed != val)
1123                 conf_changed_callback();
1124
1125         conf_changed = val;
1126 }
1127
1128 bool conf_get_changed(void)
1129 {
1130         return conf_changed;
1131 }
1132
1133 void conf_set_changed_callback(void (*fn)(void))
1134 {
1135         conf_changed_callback = fn;
1136 }
1137
1138 void set_all_choice_values(struct symbol *csym)
1139 {
1140         struct property *prop;
1141         struct symbol *sym;
1142         struct expr *e;
1143
1144         prop = sym_get_choice_prop(csym);
1145
1146         /*
1147          * Set all non-assinged choice values to no
1148          */
1149         expr_list_for_each_sym(prop->expr, e, sym) {
1150                 if (!sym_has_value(sym))
1151                         sym->def[S_DEF_USER].tri = no;
1152         }
1153         csym->flags |= SYMBOL_DEF_USER;
1154         /* clear VALID to get value calculated */
1155         csym->flags &= ~(SYMBOL_VALID | SYMBOL_NEED_SET_CHOICE_VALUES);
1156 }