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