xref: /linux-6.15/scripts/kconfig/confdata.c (revision bffbf6e2)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2002 Roman Zippel <[email protected]>
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 	const char *s;
134 	char *d, c;
135 
136 	/* check overflow: prefix + name + ".h" + '\0' must fit in buffer. */
137 	if (depfile_prefix_len + strlen(name) + 3 > sizeof(depfile_path))
138 		return -1;
139 
140 	d = depfile_path + depfile_prefix_len;
141 	s = name;
142 
143 	while ((c = *s++))
144 		*d++ = (c == '_') ? '/' : tolower(c);
145 	strcpy(d, ".h");
146 
147 	/* Assume directory path already exists. */
148 	fd = open(depfile_path, O_WRONLY | O_CREAT | O_TRUNC, 0644);
149 	if (fd == -1) {
150 		if (errno != ENOENT)
151 			return -1;
152 
153 		ret = make_parent_dir(depfile_path);
154 		if (ret)
155 			return ret;
156 
157 		/* Try it again. */
158 		fd = open(depfile_path, O_WRONLY | O_CREAT | O_TRUNC, 0644);
159 		if (fd == -1)
160 			return -1;
161 	}
162 	close(fd);
163 
164 	return 0;
165 }
166 
167 struct conf_printer {
168 	void (*print_symbol)(FILE *, struct symbol *, const char *, void *);
169 	void (*print_comment)(FILE *, const char *, void *);
170 };
171 
172 static void conf_warning(const char *fmt, ...)
173 	__attribute__ ((format (printf, 1, 2)));
174 
175 static void conf_message(const char *fmt, ...)
176 	__attribute__ ((format (printf, 1, 2)));
177 
178 static const char *conf_filename;
179 static int conf_lineno, conf_warnings;
180 
181 static void conf_warning(const char *fmt, ...)
182 {
183 	va_list ap;
184 	va_start(ap, fmt);
185 	fprintf(stderr, "%s:%d:warning: ", conf_filename, conf_lineno);
186 	vfprintf(stderr, fmt, ap);
187 	fprintf(stderr, "\n");
188 	va_end(ap);
189 	conf_warnings++;
190 }
191 
192 static void conf_default_message_callback(const char *s)
193 {
194 	printf("#\n# ");
195 	printf("%s", s);
196 	printf("\n#\n");
197 }
198 
199 static void (*conf_message_callback)(const char *s) =
200 	conf_default_message_callback;
201 void conf_set_message_callback(void (*fn)(const char *s))
202 {
203 	conf_message_callback = fn;
204 }
205 
206 static void conf_message(const char *fmt, ...)
207 {
208 	va_list ap;
209 	char buf[4096];
210 
211 	if (!conf_message_callback)
212 		return;
213 
214 	va_start(ap, fmt);
215 
216 	vsnprintf(buf, sizeof(buf), fmt, ap);
217 	conf_message_callback(buf);
218 	va_end(ap);
219 }
220 
221 const char *conf_get_configname(void)
222 {
223 	char *name = getenv("KCONFIG_CONFIG");
224 
225 	return name ? name : ".config";
226 }
227 
228 static const char *conf_get_autoconfig_name(void)
229 {
230 	char *name = getenv("KCONFIG_AUTOCONFIG");
231 
232 	return name ? name : "include/config/auto.conf";
233 }
234 
235 static int conf_set_sym_val(struct symbol *sym, int def, int def_flags, char *p)
236 {
237 	char *p2;
238 
239 	switch (sym->type) {
240 	case S_TRISTATE:
241 		if (p[0] == 'm') {
242 			sym->def[def].tri = mod;
243 			sym->flags |= def_flags;
244 			break;
245 		}
246 		/* fall through */
247 	case S_BOOLEAN:
248 		if (p[0] == 'y') {
249 			sym->def[def].tri = yes;
250 			sym->flags |= def_flags;
251 			break;
252 		}
253 		if (p[0] == 'n') {
254 			sym->def[def].tri = no;
255 			sym->flags |= def_flags;
256 			break;
257 		}
258 		if (def != S_DEF_AUTO)
259 			conf_warning("symbol value '%s' invalid for %s",
260 				     p, sym->name);
261 		return 1;
262 	case S_STRING:
263 		if (*p++ != '"')
264 			break;
265 		for (p2 = p; (p2 = strpbrk(p2, "\"\\")); p2++) {
266 			if (*p2 == '"') {
267 				*p2 = 0;
268 				break;
269 			}
270 			memmove(p2, p2 + 1, strlen(p2));
271 		}
272 		if (!p2) {
273 			if (def != S_DEF_AUTO)
274 				conf_warning("invalid string found");
275 			return 1;
276 		}
277 		/* fall through */
278 	case S_INT:
279 	case S_HEX:
280 		if (sym_string_valid(sym, p)) {
281 			sym->def[def].val = xstrdup(p);
282 			sym->flags |= def_flags;
283 		} else {
284 			if (def != S_DEF_AUTO)
285 				conf_warning("symbol value '%s' invalid for %s",
286 					     p, sym->name);
287 			return 1;
288 		}
289 		break;
290 	default:
291 		;
292 	}
293 	return 0;
294 }
295 
296 #define LINE_GROWTH 16
297 static int add_byte(int c, char **lineptr, size_t slen, size_t *n)
298 {
299 	char *nline;
300 	size_t new_size = slen + 1;
301 	if (new_size > *n) {
302 		new_size += LINE_GROWTH - 1;
303 		new_size *= 2;
304 		nline = xrealloc(*lineptr, new_size);
305 		if (!nline)
306 			return -1;
307 
308 		*lineptr = nline;
309 		*n = new_size;
310 	}
311 
312 	(*lineptr)[slen] = c;
313 
314 	return 0;
315 }
316 
317 static ssize_t compat_getline(char **lineptr, size_t *n, FILE *stream)
318 {
319 	char *line = *lineptr;
320 	size_t slen = 0;
321 
322 	for (;;) {
323 		int c = getc(stream);
324 
325 		switch (c) {
326 		case '\n':
327 			if (add_byte(c, &line, slen, n) < 0)
328 				goto e_out;
329 			slen++;
330 			/* fall through */
331 		case EOF:
332 			if (add_byte('\0', &line, slen, n) < 0)
333 				goto e_out;
334 			*lineptr = line;
335 			if (slen == 0)
336 				return -1;
337 			return slen;
338 		default:
339 			if (add_byte(c, &line, slen, n) < 0)
340 				goto e_out;
341 			slen++;
342 		}
343 	}
344 
345 e_out:
346 	line[slen-1] = '\0';
347 	*lineptr = line;
348 	return -1;
349 }
350 
351 int conf_read_simple(const char *name, int def)
352 {
353 	FILE *in = NULL;
354 	char   *line = NULL;
355 	size_t  line_asize = 0;
356 	char *p, *p2;
357 	struct symbol *sym;
358 	int i, def_flags;
359 
360 	if (name) {
361 		in = zconf_fopen(name);
362 	} else {
363 		char *env;
364 
365 		name = conf_get_configname();
366 		in = zconf_fopen(name);
367 		if (in)
368 			goto load;
369 		sym_add_change_count(1);
370 
371 		env = getenv("KCONFIG_DEFCONFIG_LIST");
372 		if (!env)
373 			return 1;
374 
375 		while (1) {
376 			bool is_last;
377 
378 			while (isspace(*env))
379 				env++;
380 
381 			if (!*env)
382 				break;
383 
384 			p = env;
385 			while (*p && !isspace(*p))
386 				p++;
387 
388 			is_last = (*p == '\0');
389 
390 			*p = '\0';
391 
392 			in = zconf_fopen(env);
393 			if (in) {
394 				conf_message("using defaults found in %s",
395 					     env);
396 				goto load;
397 			}
398 
399 			if (is_last)
400 				break;
401 
402 			env = p + 1;
403 		}
404 	}
405 	if (!in)
406 		return 1;
407 
408 load:
409 	conf_filename = name;
410 	conf_lineno = 0;
411 	conf_warnings = 0;
412 
413 	def_flags = SYMBOL_DEF << def;
414 	for_all_symbols(i, sym) {
415 		sym->flags |= SYMBOL_CHANGED;
416 		sym->flags &= ~(def_flags|SYMBOL_VALID);
417 		if (sym_is_choice(sym))
418 			sym->flags |= def_flags;
419 		switch (sym->type) {
420 		case S_INT:
421 		case S_HEX:
422 		case S_STRING:
423 			if (sym->def[def].val)
424 				free(sym->def[def].val);
425 			/* fall through */
426 		default:
427 			sym->def[def].val = NULL;
428 			sym->def[def].tri = no;
429 		}
430 	}
431 
432 	while (compat_getline(&line, &line_asize, in) != -1) {
433 		conf_lineno++;
434 		sym = NULL;
435 		if (line[0] == '#') {
436 			if (memcmp(line + 2, CONFIG_, strlen(CONFIG_)))
437 				continue;
438 			p = strchr(line + 2 + strlen(CONFIG_), ' ');
439 			if (!p)
440 				continue;
441 			*p++ = 0;
442 			if (strncmp(p, "is not set", 10))
443 				continue;
444 			if (def == S_DEF_USER) {
445 				sym = sym_find(line + 2 + strlen(CONFIG_));
446 				if (!sym) {
447 					sym_add_change_count(1);
448 					continue;
449 				}
450 			} else {
451 				sym = sym_lookup(line + 2 + strlen(CONFIG_), 0);
452 				if (sym->type == S_UNKNOWN)
453 					sym->type = S_BOOLEAN;
454 			}
455 			if (sym->flags & def_flags) {
456 				conf_warning("override: reassigning to symbol %s", sym->name);
457 			}
458 			switch (sym->type) {
459 			case S_BOOLEAN:
460 			case S_TRISTATE:
461 				sym->def[def].tri = no;
462 				sym->flags |= def_flags;
463 				break;
464 			default:
465 				;
466 			}
467 		} else if (memcmp(line, CONFIG_, strlen(CONFIG_)) == 0) {
468 			p = strchr(line + strlen(CONFIG_), '=');
469 			if (!p)
470 				continue;
471 			*p++ = 0;
472 			p2 = strchr(p, '\n');
473 			if (p2) {
474 				*p2-- = 0;
475 				if (*p2 == '\r')
476 					*p2 = 0;
477 			}
478 
479 			sym = sym_find(line + strlen(CONFIG_));
480 			if (!sym) {
481 				if (def == S_DEF_AUTO)
482 					/*
483 					 * Reading from include/config/auto.conf
484 					 * If CONFIG_FOO previously existed in
485 					 * auto.conf but it is missing now,
486 					 * include/config/foo.h must be touched.
487 					 */
488 					conf_touch_dep(line + strlen(CONFIG_));
489 				else
490 					sym_add_change_count(1);
491 				continue;
492 			}
493 
494 			if (sym->flags & def_flags) {
495 				conf_warning("override: reassigning to symbol %s", sym->name);
496 			}
497 			if (conf_set_sym_val(sym, def, def_flags, p))
498 				continue;
499 		} else {
500 			if (line[0] != '\r' && line[0] != '\n')
501 				conf_warning("unexpected data: %.*s",
502 					     (int)strcspn(line, "\r\n"), line);
503 
504 			continue;
505 		}
506 
507 		if (sym && sym_is_choice_value(sym)) {
508 			struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
509 			switch (sym->def[def].tri) {
510 			case no:
511 				break;
512 			case mod:
513 				if (cs->def[def].tri == yes) {
514 					conf_warning("%s creates inconsistent choice state", sym->name);
515 					cs->flags &= ~def_flags;
516 				}
517 				break;
518 			case yes:
519 				if (cs->def[def].tri != no)
520 					conf_warning("override: %s changes choice state", sym->name);
521 				cs->def[def].val = sym;
522 				break;
523 			}
524 			cs->def[def].tri = EXPR_OR(cs->def[def].tri, sym->def[def].tri);
525 		}
526 	}
527 	free(line);
528 	fclose(in);
529 	return 0;
530 }
531 
532 int conf_read(const char *name)
533 {
534 	struct symbol *sym;
535 	int conf_unsaved = 0;
536 	int i;
537 
538 	sym_set_change_count(0);
539 
540 	if (conf_read_simple(name, S_DEF_USER)) {
541 		sym_calc_value(modules_sym);
542 		return 1;
543 	}
544 
545 	sym_calc_value(modules_sym);
546 
547 	for_all_symbols(i, sym) {
548 		sym_calc_value(sym);
549 		if (sym_is_choice(sym) || (sym->flags & SYMBOL_NO_WRITE))
550 			continue;
551 		if (sym_has_value(sym) && (sym->flags & SYMBOL_WRITE)) {
552 			/* check that calculated value agrees with saved value */
553 			switch (sym->type) {
554 			case S_BOOLEAN:
555 			case S_TRISTATE:
556 				if (sym->def[S_DEF_USER].tri == sym_get_tristate_value(sym))
557 					continue;
558 				break;
559 			default:
560 				if (!strcmp(sym->curr.val, sym->def[S_DEF_USER].val))
561 					continue;
562 				break;
563 			}
564 		} else if (!sym_has_value(sym) && !(sym->flags & SYMBOL_WRITE))
565 			/* no previous value and not saved */
566 			continue;
567 		conf_unsaved++;
568 		/* maybe print value in verbose mode... */
569 	}
570 
571 	for_all_symbols(i, sym) {
572 		if (sym_has_value(sym) && !sym_is_choice_value(sym)) {
573 			/* Reset values of generates values, so they'll appear
574 			 * as new, if they should become visible, but that
575 			 * doesn't quite work if the Kconfig and the saved
576 			 * configuration disagree.
577 			 */
578 			if (sym->visible == no && !conf_unsaved)
579 				sym->flags &= ~SYMBOL_DEF_USER;
580 			switch (sym->type) {
581 			case S_STRING:
582 			case S_INT:
583 			case S_HEX:
584 				/* Reset a string value if it's out of range */
585 				if (sym_string_within_range(sym, sym->def[S_DEF_USER].val))
586 					break;
587 				sym->flags &= ~(SYMBOL_VALID|SYMBOL_DEF_USER);
588 				conf_unsaved++;
589 				break;
590 			default:
591 				break;
592 			}
593 		}
594 	}
595 
596 	sym_add_change_count(conf_warnings || conf_unsaved);
597 
598 	return 0;
599 }
600 
601 /*
602  * Kconfig configuration printer
603  *
604  * This printer is used when generating the resulting configuration after
605  * kconfig invocation and `defconfig' files. Unset symbol might be omitted by
606  * passing a non-NULL argument to the printer.
607  *
608  */
609 static void
610 kconfig_print_symbol(FILE *fp, struct symbol *sym, const char *value, void *arg)
611 {
612 
613 	switch (sym->type) {
614 	case S_BOOLEAN:
615 	case S_TRISTATE:
616 		if (*value == 'n') {
617 			bool skip_unset = (arg != NULL);
618 
619 			if (!skip_unset)
620 				fprintf(fp, "# %s%s is not set\n",
621 				    CONFIG_, sym->name);
622 			return;
623 		}
624 		break;
625 	default:
626 		break;
627 	}
628 
629 	fprintf(fp, "%s%s=%s\n", CONFIG_, sym->name, value);
630 }
631 
632 static void
633 kconfig_print_comment(FILE *fp, const char *value, void *arg)
634 {
635 	const char *p = value;
636 	size_t l;
637 
638 	for (;;) {
639 		l = strcspn(p, "\n");
640 		fprintf(fp, "#");
641 		if (l) {
642 			fprintf(fp, " ");
643 			xfwrite(p, l, 1, fp);
644 			p += l;
645 		}
646 		fprintf(fp, "\n");
647 		if (*p++ == '\0')
648 			break;
649 	}
650 }
651 
652 static struct conf_printer kconfig_printer_cb =
653 {
654 	.print_symbol = kconfig_print_symbol,
655 	.print_comment = kconfig_print_comment,
656 };
657 
658 /*
659  * Header printer
660  *
661  * This printer is used when generating the `include/generated/autoconf.h' file.
662  */
663 static void
664 header_print_symbol(FILE *fp, struct symbol *sym, const char *value, void *arg)
665 {
666 
667 	switch (sym->type) {
668 	case S_BOOLEAN:
669 	case S_TRISTATE: {
670 		const char *suffix = "";
671 
672 		switch (*value) {
673 		case 'n':
674 			break;
675 		case 'm':
676 			suffix = "_MODULE";
677 			/* fall through */
678 		default:
679 			fprintf(fp, "#define %s%s%s 1\n",
680 			    CONFIG_, sym->name, suffix);
681 		}
682 		break;
683 	}
684 	case S_HEX: {
685 		const char *prefix = "";
686 
687 		if (value[0] != '0' || (value[1] != 'x' && value[1] != 'X'))
688 			prefix = "0x";
689 		fprintf(fp, "#define %s%s %s%s\n",
690 		    CONFIG_, sym->name, prefix, value);
691 		break;
692 	}
693 	case S_STRING:
694 	case S_INT:
695 		fprintf(fp, "#define %s%s %s\n",
696 		    CONFIG_, sym->name, value);
697 		break;
698 	default:
699 		break;
700 	}
701 
702 }
703 
704 static void
705 header_print_comment(FILE *fp, const char *value, void *arg)
706 {
707 	const char *p = value;
708 	size_t l;
709 
710 	fprintf(fp, "/*\n");
711 	for (;;) {
712 		l = strcspn(p, "\n");
713 		fprintf(fp, " *");
714 		if (l) {
715 			fprintf(fp, " ");
716 			xfwrite(p, l, 1, fp);
717 			p += l;
718 		}
719 		fprintf(fp, "\n");
720 		if (*p++ == '\0')
721 			break;
722 	}
723 	fprintf(fp, " */\n");
724 }
725 
726 static struct conf_printer header_printer_cb =
727 {
728 	.print_symbol = header_print_symbol,
729 	.print_comment = header_print_comment,
730 };
731 
732 static void conf_write_symbol(FILE *fp, struct symbol *sym,
733 			      struct conf_printer *printer, void *printer_arg)
734 {
735 	const char *str;
736 
737 	switch (sym->type) {
738 	case S_UNKNOWN:
739 		break;
740 	case S_STRING:
741 		str = sym_get_string_value(sym);
742 		str = sym_escape_string_value(str);
743 		printer->print_symbol(fp, sym, str, printer_arg);
744 		free((void *)str);
745 		break;
746 	default:
747 		str = sym_get_string_value(sym);
748 		printer->print_symbol(fp, sym, str, printer_arg);
749 	}
750 }
751 
752 static void
753 conf_write_heading(FILE *fp, struct conf_printer *printer, void *printer_arg)
754 {
755 	char buf[256];
756 
757 	snprintf(buf, sizeof(buf),
758 	    "\n"
759 	    "Automatically generated file; DO NOT EDIT.\n"
760 	    "%s\n",
761 	    rootmenu.prompt->text);
762 
763 	printer->print_comment(fp, buf, printer_arg);
764 }
765 
766 /*
767  * Write out a minimal config.
768  * All values that has default values are skipped as this is redundant.
769  */
770 int conf_write_defconfig(const char *filename)
771 {
772 	struct symbol *sym;
773 	struct menu *menu;
774 	FILE *out;
775 
776 	out = fopen(filename, "w");
777 	if (!out)
778 		return 1;
779 
780 	sym_clear_all_valid();
781 
782 	/* Traverse all menus to find all relevant symbols */
783 	menu = rootmenu.list;
784 
785 	while (menu != NULL)
786 	{
787 		sym = menu->sym;
788 		if (sym == NULL) {
789 			if (!menu_is_visible(menu))
790 				goto next_menu;
791 		} else if (!sym_is_choice(sym)) {
792 			sym_calc_value(sym);
793 			if (!(sym->flags & SYMBOL_WRITE))
794 				goto next_menu;
795 			sym->flags &= ~SYMBOL_WRITE;
796 			/* If we cannot change the symbol - skip */
797 			if (!sym_is_changeable(sym))
798 				goto next_menu;
799 			/* If symbol equals to default value - skip */
800 			if (strcmp(sym_get_string_value(sym), sym_get_string_default(sym)) == 0)
801 				goto next_menu;
802 
803 			/*
804 			 * If symbol is a choice value and equals to the
805 			 * default for a choice - skip.
806 			 * But only if value is bool and equal to "y" and
807 			 * choice is not "optional".
808 			 * (If choice is "optional" then all values can be "n")
809 			 */
810 			if (sym_is_choice_value(sym)) {
811 				struct symbol *cs;
812 				struct symbol *ds;
813 
814 				cs = prop_get_symbol(sym_get_choice_prop(sym));
815 				ds = sym_choice_default(cs);
816 				if (!sym_is_optional(cs) && sym == ds) {
817 					if ((sym->type == S_BOOLEAN) &&
818 					    sym_get_tristate_value(sym) == yes)
819 						goto next_menu;
820 				}
821 			}
822 			conf_write_symbol(out, sym, &kconfig_printer_cb, NULL);
823 		}
824 next_menu:
825 		if (menu->list != NULL) {
826 			menu = menu->list;
827 		}
828 		else if (menu->next != NULL) {
829 			menu = menu->next;
830 		} else {
831 			while ((menu = menu->parent)) {
832 				if (menu->next != NULL) {
833 					menu = menu->next;
834 					break;
835 				}
836 			}
837 		}
838 	}
839 	fclose(out);
840 	return 0;
841 }
842 
843 int conf_write(const char *name)
844 {
845 	FILE *out;
846 	struct symbol *sym;
847 	struct menu *menu;
848 	const char *str;
849 	char tmpname[PATH_MAX + 1], oldname[PATH_MAX + 1];
850 	char *env;
851 	int i;
852 	bool need_newline = false;
853 
854 	if (!name)
855 		name = conf_get_configname();
856 
857 	if (!*name) {
858 		fprintf(stderr, "config name is empty\n");
859 		return -1;
860 	}
861 
862 	if (is_dir(name)) {
863 		fprintf(stderr, "%s: Is a directory\n", name);
864 		return -1;
865 	}
866 
867 	if (make_parent_dir(name))
868 		return -1;
869 
870 	env = getenv("KCONFIG_OVERWRITECONFIG");
871 	if (env && *env) {
872 		*tmpname = 0;
873 		out = fopen(name, "w");
874 	} else {
875 		snprintf(tmpname, sizeof(tmpname), "%s.%d.tmp",
876 			 name, (int)getpid());
877 		out = fopen(tmpname, "w");
878 	}
879 	if (!out)
880 		return 1;
881 
882 	conf_write_heading(out, &kconfig_printer_cb, NULL);
883 
884 	if (!conf_get_changed())
885 		sym_clear_all_valid();
886 
887 	menu = rootmenu.list;
888 	while (menu) {
889 		sym = menu->sym;
890 		if (!sym) {
891 			if (!menu_is_visible(menu))
892 				goto next;
893 			str = menu_get_prompt(menu);
894 			fprintf(out, "\n"
895 				     "#\n"
896 				     "# %s\n"
897 				     "#\n", str);
898 			need_newline = false;
899 		} else if (!(sym->flags & SYMBOL_CHOICE) &&
900 			   !(sym->flags & SYMBOL_WRITTEN)) {
901 			sym_calc_value(sym);
902 			if (!(sym->flags & SYMBOL_WRITE))
903 				goto next;
904 			if (need_newline) {
905 				fprintf(out, "\n");
906 				need_newline = false;
907 			}
908 			sym->flags |= SYMBOL_WRITTEN;
909 			conf_write_symbol(out, sym, &kconfig_printer_cb, NULL);
910 		}
911 
912 next:
913 		if (menu->list) {
914 			menu = menu->list;
915 			continue;
916 		}
917 		if (menu->next)
918 			menu = menu->next;
919 		else while ((menu = menu->parent)) {
920 			if (!menu->sym && menu_is_visible(menu) &&
921 			    menu != &rootmenu) {
922 				str = menu_get_prompt(menu);
923 				fprintf(out, "# end of %s\n", str);
924 				need_newline = true;
925 			}
926 			if (menu->next) {
927 				menu = menu->next;
928 				break;
929 			}
930 		}
931 	}
932 	fclose(out);
933 
934 	for_all_symbols(i, sym)
935 		sym->flags &= ~SYMBOL_WRITTEN;
936 
937 	if (*tmpname) {
938 		if (is_same(name, tmpname)) {
939 			conf_message("No change to %s", name);
940 			unlink(tmpname);
941 			sym_set_change_count(0);
942 			return 0;
943 		}
944 
945 		snprintf(oldname, sizeof(oldname), "%s.old", name);
946 		rename(name, oldname);
947 		if (rename(tmpname, name))
948 			return 1;
949 	}
950 
951 	conf_message("configuration written to %s", name);
952 
953 	sym_set_change_count(0);
954 
955 	return 0;
956 }
957 
958 /* write a dependency file as used by kbuild to track dependencies */
959 static int conf_write_dep(const char *name)
960 {
961 	struct file *file;
962 	FILE *out;
963 
964 	out = fopen("..config.tmp", "w");
965 	if (!out)
966 		return 1;
967 	fprintf(out, "deps_config := \\\n");
968 	for (file = file_list; file; file = file->next) {
969 		if (file->next)
970 			fprintf(out, "\t%s \\\n", file->name);
971 		else
972 			fprintf(out, "\t%s\n", file->name);
973 	}
974 	fprintf(out, "\n%s: \\\n"
975 		     "\t$(deps_config)\n\n", conf_get_autoconfig_name());
976 
977 	env_write_dep(out, conf_get_autoconfig_name());
978 
979 	fprintf(out, "\n$(deps_config): ;\n");
980 	fclose(out);
981 
982 	if (make_parent_dir(name))
983 		return 1;
984 	rename("..config.tmp", name);
985 	return 0;
986 }
987 
988 static int conf_touch_deps(void)
989 {
990 	const char *name;
991 	struct symbol *sym;
992 	int res, i;
993 
994 	strcpy(depfile_path, "include/config/");
995 	depfile_prefix_len = strlen(depfile_path);
996 
997 	name = conf_get_autoconfig_name();
998 	conf_read_simple(name, S_DEF_AUTO);
999 	sym_calc_value(modules_sym);
1000 
1001 	for_all_symbols(i, sym) {
1002 		sym_calc_value(sym);
1003 		if ((sym->flags & SYMBOL_NO_WRITE) || !sym->name)
1004 			continue;
1005 		if (sym->flags & SYMBOL_WRITE) {
1006 			if (sym->flags & SYMBOL_DEF_AUTO) {
1007 				/*
1008 				 * symbol has old and new value,
1009 				 * so compare them...
1010 				 */
1011 				switch (sym->type) {
1012 				case S_BOOLEAN:
1013 				case S_TRISTATE:
1014 					if (sym_get_tristate_value(sym) ==
1015 					    sym->def[S_DEF_AUTO].tri)
1016 						continue;
1017 					break;
1018 				case S_STRING:
1019 				case S_HEX:
1020 				case S_INT:
1021 					if (!strcmp(sym_get_string_value(sym),
1022 						    sym->def[S_DEF_AUTO].val))
1023 						continue;
1024 					break;
1025 				default:
1026 					break;
1027 				}
1028 			} else {
1029 				/*
1030 				 * If there is no old value, only 'no' (unset)
1031 				 * is allowed as new value.
1032 				 */
1033 				switch (sym->type) {
1034 				case S_BOOLEAN:
1035 				case S_TRISTATE:
1036 					if (sym_get_tristate_value(sym) == no)
1037 						continue;
1038 					break;
1039 				default:
1040 					break;
1041 				}
1042 			}
1043 		} else if (!(sym->flags & SYMBOL_DEF_AUTO))
1044 			/* There is neither an old nor a new value. */
1045 			continue;
1046 		/* else
1047 		 *	There is an old value, but no new value ('no' (unset)
1048 		 *	isn't saved in auto.conf, so the old value is always
1049 		 *	different from 'no').
1050 		 */
1051 
1052 		res = conf_touch_dep(sym->name);
1053 		if (res)
1054 			return res;
1055 	}
1056 
1057 	return 0;
1058 }
1059 
1060 int conf_write_autoconf(int overwrite)
1061 {
1062 	struct symbol *sym;
1063 	const char *name;
1064 	const char *autoconf_name = conf_get_autoconfig_name();
1065 	FILE *out, *out_h;
1066 	int i;
1067 
1068 	if (!overwrite && is_present(autoconf_name))
1069 		return 0;
1070 
1071 	conf_write_dep("include/config/auto.conf.cmd");
1072 
1073 	if (conf_touch_deps())
1074 		return 1;
1075 
1076 	out = fopen(".tmpconfig", "w");
1077 	if (!out)
1078 		return 1;
1079 
1080 	out_h = fopen(".tmpconfig.h", "w");
1081 	if (!out_h) {
1082 		fclose(out);
1083 		return 1;
1084 	}
1085 
1086 	conf_write_heading(out, &kconfig_printer_cb, NULL);
1087 	conf_write_heading(out_h, &header_printer_cb, NULL);
1088 
1089 	for_all_symbols(i, sym) {
1090 		sym_calc_value(sym);
1091 		if (!(sym->flags & SYMBOL_WRITE) || !sym->name)
1092 			continue;
1093 
1094 		/* write symbols to auto.conf and autoconf.h */
1095 		conf_write_symbol(out, sym, &kconfig_printer_cb, (void *)1);
1096 		conf_write_symbol(out_h, sym, &header_printer_cb, NULL);
1097 	}
1098 	fclose(out);
1099 	fclose(out_h);
1100 
1101 	name = getenv("KCONFIG_AUTOHEADER");
1102 	if (!name)
1103 		name = "include/generated/autoconf.h";
1104 	if (make_parent_dir(name))
1105 		return 1;
1106 	if (rename(".tmpconfig.h", name))
1107 		return 1;
1108 
1109 	if (make_parent_dir(autoconf_name))
1110 		return 1;
1111 	/*
1112 	 * This must be the last step, kbuild has a dependency on auto.conf
1113 	 * and this marks the successful completion of the previous steps.
1114 	 */
1115 	if (rename(".tmpconfig", autoconf_name))
1116 		return 1;
1117 
1118 	return 0;
1119 }
1120 
1121 static int sym_change_count;
1122 static void (*conf_changed_callback)(void);
1123 
1124 void sym_set_change_count(int count)
1125 {
1126 	int _sym_change_count = sym_change_count;
1127 	sym_change_count = count;
1128 	if (conf_changed_callback &&
1129 	    (bool)_sym_change_count != (bool)count)
1130 		conf_changed_callback();
1131 }
1132 
1133 void sym_add_change_count(int count)
1134 {
1135 	sym_set_change_count(count + sym_change_count);
1136 }
1137 
1138 bool conf_get_changed(void)
1139 {
1140 	return sym_change_count;
1141 }
1142 
1143 void conf_set_changed_callback(void (*fn)(void))
1144 {
1145 	conf_changed_callback = fn;
1146 }
1147 
1148 void set_all_choice_values(struct symbol *csym)
1149 {
1150 	struct property *prop;
1151 	struct symbol *sym;
1152 	struct expr *e;
1153 
1154 	prop = sym_get_choice_prop(csym);
1155 
1156 	/*
1157 	 * Set all non-assinged choice values to no
1158 	 */
1159 	expr_list_for_each_sym(prop->expr, e, sym) {
1160 		if (!sym_has_value(sym))
1161 			sym->def[S_DEF_USER].tri = no;
1162 	}
1163 	csym->flags |= SYMBOL_DEF_USER;
1164 	/* clear VALID to get value calculated */
1165 	csym->flags &= ~(SYMBOL_VALID | SYMBOL_NEED_SET_CHOICE_VALUES);
1166 }
1167