xref: /openbmc/linux/scripts/kconfig/confdata.c (revision e15a5365)
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 <ctype.h>
9 #include <errno.h>
10 #include <fcntl.h>
11 #include <limits.h>
12 #include <stdarg.h>
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <string.h>
16 #include <time.h>
17 #include <unistd.h>
18 
19 #include "lkc.h"
20 
21 /* return true if 'path' exists, false otherwise */
22 static bool is_present(const char *path)
23 {
24 	struct stat st;
25 
26 	return !stat(path, &st);
27 }
28 
29 /* return true if 'path' exists and it is a directory, false otherwise */
30 static bool is_dir(const char *path)
31 {
32 	struct stat st;
33 
34 	if (stat(path, &st))
35 		return 0;
36 
37 	return S_ISDIR(st.st_mode);
38 }
39 
40 /* return true if the given two files are the same, false otherwise */
41 static bool is_same(const char *file1, const char *file2)
42 {
43 	int fd1, fd2;
44 	struct stat st1, st2;
45 	void *map1, *map2;
46 	bool ret = false;
47 
48 	fd1 = open(file1, O_RDONLY);
49 	if (fd1 < 0)
50 		return ret;
51 
52 	fd2 = open(file2, O_RDONLY);
53 	if (fd2 < 0)
54 		goto close1;
55 
56 	ret = fstat(fd1, &st1);
57 	if (ret)
58 		goto close2;
59 	ret = fstat(fd2, &st2);
60 	if (ret)
61 		goto close2;
62 
63 	if (st1.st_size != st2.st_size)
64 		goto close2;
65 
66 	map1 = mmap(NULL, st1.st_size, PROT_READ, MAP_PRIVATE, fd1, 0);
67 	if (map1 == MAP_FAILED)
68 		goto close2;
69 
70 	map2 = mmap(NULL, st2.st_size, PROT_READ, MAP_PRIVATE, fd2, 0);
71 	if (map2 == MAP_FAILED)
72 		goto close2;
73 
74 	if (bcmp(map1, map2, st1.st_size))
75 		goto close2;
76 
77 	ret = true;
78 close2:
79 	close(fd2);
80 close1:
81 	close(fd1);
82 
83 	return ret;
84 }
85 
86 /*
87  * Create the parent directory of the given path.
88  *
89  * For example, if 'include/config/auto.conf' is given, create 'include/config'.
90  */
91 static int make_parent_dir(const char *path)
92 {
93 	char tmp[PATH_MAX + 1];
94 	char *p;
95 
96 	strncpy(tmp, path, sizeof(tmp));
97 	tmp[sizeof(tmp) - 1] = 0;
98 
99 	/* Remove the base name. Just return if nothing is left */
100 	p = strrchr(tmp, '/');
101 	if (!p)
102 		return 0;
103 	*(p + 1) = 0;
104 
105 	/* Just in case it is an absolute path */
106 	p = tmp;
107 	while (*p == '/')
108 		p++;
109 
110 	while ((p = strchr(p, '/'))) {
111 		*p = 0;
112 
113 		/* skip if the directory exists */
114 		if (!is_dir(tmp) && mkdir(tmp, 0755))
115 			return -1;
116 
117 		*p = '/';
118 		while (*p == '/')
119 			p++;
120 	}
121 
122 	return 0;
123 }
124 
125 static char depfile_path[PATH_MAX];
126 static size_t depfile_prefix_len;
127 
128 /* touch depfile for symbol 'name' */
129 static int conf_touch_dep(const char *name)
130 {
131 	int fd, ret;
132 	const char *s;
133 	char *d, c;
134 
135 	/* check overflow: prefix + name + ".h" + '\0' must fit in buffer. */
136 	if (depfile_prefix_len + strlen(name) + 3 > sizeof(depfile_path))
137 		return -1;
138 
139 	d = depfile_path + depfile_prefix_len;
140 	s = name;
141 
142 	while ((c = *s++))
143 		*d++ = (c == '_') ? '/' : tolower(c);
144 	strcpy(d, ".h");
145 
146 	/* Assume directory path already exists. */
147 	fd = open(depfile_path, O_WRONLY | O_CREAT | O_TRUNC, 0644);
148 	if (fd == -1) {
149 		if (errno != ENOENT)
150 			return -1;
151 
152 		ret = make_parent_dir(depfile_path);
153 		if (ret)
154 			return ret;
155 
156 		/* Try it again. */
157 		fd = open(depfile_path, O_WRONLY | O_CREAT | O_TRUNC, 0644);
158 		if (fd == -1)
159 			return -1;
160 	}
161 	close(fd);
162 
163 	return 0;
164 }
165 
166 struct conf_printer {
167 	void (*print_symbol)(FILE *, struct symbol *, const char *, void *);
168 	void (*print_comment)(FILE *, const char *, void *);
169 };
170 
171 static void conf_warning(const char *fmt, ...)
172 	__attribute__ ((format (printf, 1, 2)));
173 
174 static void conf_message(const char *fmt, ...)
175 	__attribute__ ((format (printf, 1, 2)));
176 
177 static const char *conf_filename;
178 static int conf_lineno, conf_warnings;
179 
180 static void conf_warning(const char *fmt, ...)
181 {
182 	va_list ap;
183 	va_start(ap, fmt);
184 	fprintf(stderr, "%s:%d:warning: ", conf_filename, conf_lineno);
185 	vfprintf(stderr, fmt, ap);
186 	fprintf(stderr, "\n");
187 	va_end(ap);
188 	conf_warnings++;
189 }
190 
191 static void conf_default_message_callback(const char *s)
192 {
193 	printf("#\n# ");
194 	printf("%s", s);
195 	printf("\n#\n");
196 }
197 
198 static void (*conf_message_callback)(const char *s) =
199 	conf_default_message_callback;
200 void conf_set_message_callback(void (*fn)(const char *s))
201 {
202 	conf_message_callback = fn;
203 }
204 
205 static void conf_message(const char *fmt, ...)
206 {
207 	va_list ap;
208 	char buf[4096];
209 
210 	if (!conf_message_callback)
211 		return;
212 
213 	va_start(ap, fmt);
214 
215 	vsnprintf(buf, sizeof(buf), fmt, ap);
216 	conf_message_callback(buf);
217 	va_end(ap);
218 }
219 
220 const char *conf_get_configname(void)
221 {
222 	char *name = getenv("KCONFIG_CONFIG");
223 
224 	return name ? name : ".config";
225 }
226 
227 static const char *conf_get_autoconfig_name(void)
228 {
229 	char *name = getenv("KCONFIG_AUTOCONFIG");
230 
231 	return name ? name : "include/config/auto.conf";
232 }
233 
234 static int conf_set_sym_val(struct symbol *sym, int def, int def_flags, char *p)
235 {
236 	char *p2;
237 
238 	switch (sym->type) {
239 	case S_TRISTATE:
240 		if (p[0] == 'm') {
241 			sym->def[def].tri = mod;
242 			sym->flags |= def_flags;
243 			break;
244 		}
245 		/* fall through */
246 	case S_BOOLEAN:
247 		if (p[0] == 'y') {
248 			sym->def[def].tri = yes;
249 			sym->flags |= def_flags;
250 			break;
251 		}
252 		if (p[0] == 'n') {
253 			sym->def[def].tri = no;
254 			sym->flags |= def_flags;
255 			break;
256 		}
257 		if (def != S_DEF_AUTO)
258 			conf_warning("symbol value '%s' invalid for %s",
259 				     p, sym->name);
260 		return 1;
261 	case S_STRING:
262 		if (*p++ != '"')
263 			break;
264 		for (p2 = p; (p2 = strpbrk(p2, "\"\\")); p2++) {
265 			if (*p2 == '"') {
266 				*p2 = 0;
267 				break;
268 			}
269 			memmove(p2, p2 + 1, strlen(p2));
270 		}
271 		if (!p2) {
272 			if (def != S_DEF_AUTO)
273 				conf_warning("invalid string found");
274 			return 1;
275 		}
276 		/* fall through */
277 	case S_INT:
278 	case S_HEX:
279 		if (sym_string_valid(sym, p)) {
280 			sym->def[def].val = xstrdup(p);
281 			sym->flags |= def_flags;
282 		} else {
283 			if (def != S_DEF_AUTO)
284 				conf_warning("symbol value '%s' invalid for %s",
285 					     p, sym->name);
286 			return 1;
287 		}
288 		break;
289 	default:
290 		;
291 	}
292 	return 0;
293 }
294 
295 #define LINE_GROWTH 16
296 static int add_byte(int c, char **lineptr, size_t slen, size_t *n)
297 {
298 	char *nline;
299 	size_t new_size = slen + 1;
300 	if (new_size > *n) {
301 		new_size += LINE_GROWTH - 1;
302 		new_size *= 2;
303 		nline = xrealloc(*lineptr, new_size);
304 		if (!nline)
305 			return -1;
306 
307 		*lineptr = nline;
308 		*n = new_size;
309 	}
310 
311 	(*lineptr)[slen] = c;
312 
313 	return 0;
314 }
315 
316 static ssize_t compat_getline(char **lineptr, size_t *n, FILE *stream)
317 {
318 	char *line = *lineptr;
319 	size_t slen = 0;
320 
321 	for (;;) {
322 		int c = getc(stream);
323 
324 		switch (c) {
325 		case '\n':
326 			if (add_byte(c, &line, slen, n) < 0)
327 				goto e_out;
328 			slen++;
329 			/* fall through */
330 		case EOF:
331 			if (add_byte('\0', &line, slen, n) < 0)
332 				goto e_out;
333 			*lineptr = line;
334 			if (slen == 0)
335 				return -1;
336 			return slen;
337 		default:
338 			if (add_byte(c, &line, slen, n) < 0)
339 				goto e_out;
340 			slen++;
341 		}
342 	}
343 
344 e_out:
345 	line[slen-1] = '\0';
346 	*lineptr = line;
347 	return -1;
348 }
349 
350 int conf_read_simple(const char *name, int def)
351 {
352 	FILE *in = NULL;
353 	char   *line = NULL;
354 	size_t  line_asize = 0;
355 	char *p, *p2;
356 	struct symbol *sym;
357 	int i, def_flags;
358 
359 	if (name) {
360 		in = zconf_fopen(name);
361 	} else {
362 		struct property *prop;
363 
364 		name = conf_get_configname();
365 		in = zconf_fopen(name);
366 		if (in)
367 			goto load;
368 		sym_add_change_count(1);
369 		if (!sym_defconfig_list)
370 			return 1;
371 
372 		for_all_defaults(sym_defconfig_list, prop) {
373 			if (expr_calc_value(prop->visible.expr) == no ||
374 			    prop->expr->type != E_SYMBOL)
375 				continue;
376 			sym_calc_value(prop->expr->left.sym);
377 			name = sym_get_string_value(prop->expr->left.sym);
378 			in = zconf_fopen(name);
379 			if (in) {
380 				conf_message("using defaults found in %s",
381 					 name);
382 				goto load;
383 			}
384 		}
385 	}
386 	if (!in)
387 		return 1;
388 
389 load:
390 	conf_filename = name;
391 	conf_lineno = 0;
392 	conf_warnings = 0;
393 
394 	def_flags = SYMBOL_DEF << def;
395 	for_all_symbols(i, sym) {
396 		sym->flags |= SYMBOL_CHANGED;
397 		sym->flags &= ~(def_flags|SYMBOL_VALID);
398 		if (sym_is_choice(sym))
399 			sym->flags |= def_flags;
400 		switch (sym->type) {
401 		case S_INT:
402 		case S_HEX:
403 		case S_STRING:
404 			if (sym->def[def].val)
405 				free(sym->def[def].val);
406 			/* fall through */
407 		default:
408 			sym->def[def].val = NULL;
409 			sym->def[def].tri = no;
410 		}
411 	}
412 
413 	while (compat_getline(&line, &line_asize, in) != -1) {
414 		conf_lineno++;
415 		sym = NULL;
416 		if (line[0] == '#') {
417 			if (memcmp(line + 2, CONFIG_, strlen(CONFIG_)))
418 				continue;
419 			p = strchr(line + 2 + strlen(CONFIG_), ' ');
420 			if (!p)
421 				continue;
422 			*p++ = 0;
423 			if (strncmp(p, "is not set", 10))
424 				continue;
425 			if (def == S_DEF_USER) {
426 				sym = sym_find(line + 2 + strlen(CONFIG_));
427 				if (!sym) {
428 					sym_add_change_count(1);
429 					continue;
430 				}
431 			} else {
432 				sym = sym_lookup(line + 2 + strlen(CONFIG_), 0);
433 				if (sym->type == S_UNKNOWN)
434 					sym->type = S_BOOLEAN;
435 			}
436 			if (sym->flags & def_flags) {
437 				conf_warning("override: reassigning to symbol %s", sym->name);
438 			}
439 			switch (sym->type) {
440 			case S_BOOLEAN:
441 			case S_TRISTATE:
442 				sym->def[def].tri = no;
443 				sym->flags |= def_flags;
444 				break;
445 			default:
446 				;
447 			}
448 		} else if (memcmp(line, CONFIG_, strlen(CONFIG_)) == 0) {
449 			p = strchr(line + strlen(CONFIG_), '=');
450 			if (!p)
451 				continue;
452 			*p++ = 0;
453 			p2 = strchr(p, '\n');
454 			if (p2) {
455 				*p2-- = 0;
456 				if (*p2 == '\r')
457 					*p2 = 0;
458 			}
459 
460 			sym = sym_find(line + strlen(CONFIG_));
461 			if (!sym) {
462 				if (def == S_DEF_AUTO)
463 					/*
464 					 * Reading from include/config/auto.conf
465 					 * If CONFIG_FOO previously existed in
466 					 * auto.conf but it is missing now,
467 					 * include/config/foo.h must be touched.
468 					 */
469 					conf_touch_dep(line + strlen(CONFIG_));
470 				else
471 					sym_add_change_count(1);
472 				continue;
473 			}
474 
475 			if (sym->flags & def_flags) {
476 				conf_warning("override: reassigning to symbol %s", sym->name);
477 			}
478 			if (conf_set_sym_val(sym, def, def_flags, p))
479 				continue;
480 		} else {
481 			if (line[0] != '\r' && line[0] != '\n')
482 				conf_warning("unexpected data: %.*s",
483 					     (int)strcspn(line, "\r\n"), line);
484 
485 			continue;
486 		}
487 
488 		if (sym && sym_is_choice_value(sym)) {
489 			struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
490 			switch (sym->def[def].tri) {
491 			case no:
492 				break;
493 			case mod:
494 				if (cs->def[def].tri == yes) {
495 					conf_warning("%s creates inconsistent choice state", sym->name);
496 					cs->flags &= ~def_flags;
497 				}
498 				break;
499 			case yes:
500 				if (cs->def[def].tri != no)
501 					conf_warning("override: %s changes choice state", sym->name);
502 				cs->def[def].val = sym;
503 				break;
504 			}
505 			cs->def[def].tri = EXPR_OR(cs->def[def].tri, sym->def[def].tri);
506 		}
507 	}
508 	free(line);
509 	fclose(in);
510 	return 0;
511 }
512 
513 int conf_read(const char *name)
514 {
515 	struct symbol *sym;
516 	int conf_unsaved = 0;
517 	int i;
518 
519 	sym_set_change_count(0);
520 
521 	if (conf_read_simple(name, S_DEF_USER)) {
522 		sym_calc_value(modules_sym);
523 		return 1;
524 	}
525 
526 	sym_calc_value(modules_sym);
527 
528 	for_all_symbols(i, sym) {
529 		sym_calc_value(sym);
530 		if (sym_is_choice(sym) || (sym->flags & SYMBOL_NO_WRITE))
531 			continue;
532 		if (sym_has_value(sym) && (sym->flags & SYMBOL_WRITE)) {
533 			/* check that calculated value agrees with saved value */
534 			switch (sym->type) {
535 			case S_BOOLEAN:
536 			case S_TRISTATE:
537 				if (sym->def[S_DEF_USER].tri == sym_get_tristate_value(sym))
538 					continue;
539 				break;
540 			default:
541 				if (!strcmp(sym->curr.val, sym->def[S_DEF_USER].val))
542 					continue;
543 				break;
544 			}
545 		} else if (!sym_has_value(sym) && !(sym->flags & SYMBOL_WRITE))
546 			/* no previous value and not saved */
547 			continue;
548 		conf_unsaved++;
549 		/* maybe print value in verbose mode... */
550 	}
551 
552 	for_all_symbols(i, sym) {
553 		if (sym_has_value(sym) && !sym_is_choice_value(sym)) {
554 			/* Reset values of generates values, so they'll appear
555 			 * as new, if they should become visible, but that
556 			 * doesn't quite work if the Kconfig and the saved
557 			 * configuration disagree.
558 			 */
559 			if (sym->visible == no && !conf_unsaved)
560 				sym->flags &= ~SYMBOL_DEF_USER;
561 			switch (sym->type) {
562 			case S_STRING:
563 			case S_INT:
564 			case S_HEX:
565 				/* Reset a string value if it's out of range */
566 				if (sym_string_within_range(sym, sym->def[S_DEF_USER].val))
567 					break;
568 				sym->flags &= ~(SYMBOL_VALID|SYMBOL_DEF_USER);
569 				conf_unsaved++;
570 				break;
571 			default:
572 				break;
573 			}
574 		}
575 	}
576 
577 	sym_add_change_count(conf_warnings || conf_unsaved);
578 
579 	return 0;
580 }
581 
582 /*
583  * Kconfig configuration printer
584  *
585  * This printer is used when generating the resulting configuration after
586  * kconfig invocation and `defconfig' files. Unset symbol might be omitted by
587  * passing a non-NULL argument to the printer.
588  *
589  */
590 static void
591 kconfig_print_symbol(FILE *fp, struct symbol *sym, const char *value, void *arg)
592 {
593 
594 	switch (sym->type) {
595 	case S_BOOLEAN:
596 	case S_TRISTATE:
597 		if (*value == 'n') {
598 			bool skip_unset = (arg != NULL);
599 
600 			if (!skip_unset)
601 				fprintf(fp, "# %s%s is not set\n",
602 				    CONFIG_, sym->name);
603 			return;
604 		}
605 		break;
606 	default:
607 		break;
608 	}
609 
610 	fprintf(fp, "%s%s=%s\n", CONFIG_, sym->name, value);
611 }
612 
613 static void
614 kconfig_print_comment(FILE *fp, const char *value, void *arg)
615 {
616 	const char *p = value;
617 	size_t l;
618 
619 	for (;;) {
620 		l = strcspn(p, "\n");
621 		fprintf(fp, "#");
622 		if (l) {
623 			fprintf(fp, " ");
624 			xfwrite(p, l, 1, fp);
625 			p += l;
626 		}
627 		fprintf(fp, "\n");
628 		if (*p++ == '\0')
629 			break;
630 	}
631 }
632 
633 static struct conf_printer kconfig_printer_cb =
634 {
635 	.print_symbol = kconfig_print_symbol,
636 	.print_comment = kconfig_print_comment,
637 };
638 
639 /*
640  * Header printer
641  *
642  * This printer is used when generating the `include/generated/autoconf.h' file.
643  */
644 static void
645 header_print_symbol(FILE *fp, struct symbol *sym, const char *value, void *arg)
646 {
647 
648 	switch (sym->type) {
649 	case S_BOOLEAN:
650 	case S_TRISTATE: {
651 		const char *suffix = "";
652 
653 		switch (*value) {
654 		case 'n':
655 			break;
656 		case 'm':
657 			suffix = "_MODULE";
658 			/* fall through */
659 		default:
660 			fprintf(fp, "#define %s%s%s 1\n",
661 			    CONFIG_, sym->name, suffix);
662 		}
663 		break;
664 	}
665 	case S_HEX: {
666 		const char *prefix = "";
667 
668 		if (value[0] != '0' || (value[1] != 'x' && value[1] != 'X'))
669 			prefix = "0x";
670 		fprintf(fp, "#define %s%s %s%s\n",
671 		    CONFIG_, sym->name, prefix, value);
672 		break;
673 	}
674 	case S_STRING:
675 	case S_INT:
676 		fprintf(fp, "#define %s%s %s\n",
677 		    CONFIG_, sym->name, value);
678 		break;
679 	default:
680 		break;
681 	}
682 
683 }
684 
685 static void
686 header_print_comment(FILE *fp, const char *value, void *arg)
687 {
688 	const char *p = value;
689 	size_t l;
690 
691 	fprintf(fp, "/*\n");
692 	for (;;) {
693 		l = strcspn(p, "\n");
694 		fprintf(fp, " *");
695 		if (l) {
696 			fprintf(fp, " ");
697 			xfwrite(p, l, 1, fp);
698 			p += l;
699 		}
700 		fprintf(fp, "\n");
701 		if (*p++ == '\0')
702 			break;
703 	}
704 	fprintf(fp, " */\n");
705 }
706 
707 static struct conf_printer header_printer_cb =
708 {
709 	.print_symbol = header_print_symbol,
710 	.print_comment = header_print_comment,
711 };
712 
713 static void conf_write_symbol(FILE *fp, struct symbol *sym,
714 			      struct conf_printer *printer, void *printer_arg)
715 {
716 	const char *str;
717 
718 	switch (sym->type) {
719 	case S_UNKNOWN:
720 		break;
721 	case S_STRING:
722 		str = sym_get_string_value(sym);
723 		str = sym_escape_string_value(str);
724 		printer->print_symbol(fp, sym, str, printer_arg);
725 		free((void *)str);
726 		break;
727 	default:
728 		str = sym_get_string_value(sym);
729 		printer->print_symbol(fp, sym, str, printer_arg);
730 	}
731 }
732 
733 static void
734 conf_write_heading(FILE *fp, struct conf_printer *printer, void *printer_arg)
735 {
736 	char buf[256];
737 
738 	snprintf(buf, sizeof(buf),
739 	    "\n"
740 	    "Automatically generated file; DO NOT EDIT.\n"
741 	    "%s\n",
742 	    rootmenu.prompt->text);
743 
744 	printer->print_comment(fp, buf, printer_arg);
745 }
746 
747 /*
748  * Write out a minimal config.
749  * All values that has default values are skipped as this is redundant.
750  */
751 int conf_write_defconfig(const char *filename)
752 {
753 	struct symbol *sym;
754 	struct menu *menu;
755 	FILE *out;
756 
757 	out = fopen(filename, "w");
758 	if (!out)
759 		return 1;
760 
761 	sym_clear_all_valid();
762 
763 	/* Traverse all menus to find all relevant symbols */
764 	menu = rootmenu.list;
765 
766 	while (menu != NULL)
767 	{
768 		sym = menu->sym;
769 		if (sym == NULL) {
770 			if (!menu_is_visible(menu))
771 				goto next_menu;
772 		} else if (!sym_is_choice(sym)) {
773 			sym_calc_value(sym);
774 			if (!(sym->flags & SYMBOL_WRITE))
775 				goto next_menu;
776 			sym->flags &= ~SYMBOL_WRITE;
777 			/* If we cannot change the symbol - skip */
778 			if (!sym_is_changeable(sym))
779 				goto next_menu;
780 			/* If symbol equals to default value - skip */
781 			if (strcmp(sym_get_string_value(sym), sym_get_string_default(sym)) == 0)
782 				goto next_menu;
783 
784 			/*
785 			 * If symbol is a choice value and equals to the
786 			 * default for a choice - skip.
787 			 * But only if value is bool and equal to "y" and
788 			 * choice is not "optional".
789 			 * (If choice is "optional" then all values can be "n")
790 			 */
791 			if (sym_is_choice_value(sym)) {
792 				struct symbol *cs;
793 				struct symbol *ds;
794 
795 				cs = prop_get_symbol(sym_get_choice_prop(sym));
796 				ds = sym_choice_default(cs);
797 				if (!sym_is_optional(cs) && sym == ds) {
798 					if ((sym->type == S_BOOLEAN) &&
799 					    sym_get_tristate_value(sym) == yes)
800 						goto next_menu;
801 				}
802 			}
803 			conf_write_symbol(out, sym, &kconfig_printer_cb, NULL);
804 		}
805 next_menu:
806 		if (menu->list != NULL) {
807 			menu = menu->list;
808 		}
809 		else if (menu->next != NULL) {
810 			menu = menu->next;
811 		} else {
812 			while ((menu = menu->parent)) {
813 				if (menu->next != NULL) {
814 					menu = menu->next;
815 					break;
816 				}
817 			}
818 		}
819 	}
820 	fclose(out);
821 	return 0;
822 }
823 
824 int conf_write(const char *name)
825 {
826 	FILE *out;
827 	struct symbol *sym;
828 	struct menu *menu;
829 	const char *str;
830 	char tmpname[PATH_MAX + 1], oldname[PATH_MAX + 1];
831 	char *env;
832 	int i;
833 	bool need_newline = false;
834 
835 	if (!name)
836 		name = conf_get_configname();
837 
838 	if (!*name) {
839 		fprintf(stderr, "config name is empty\n");
840 		return -1;
841 	}
842 
843 	if (is_dir(name)) {
844 		fprintf(stderr, "%s: Is a directory\n", name);
845 		return -1;
846 	}
847 
848 	if (make_parent_dir(name))
849 		return -1;
850 
851 	env = getenv("KCONFIG_OVERWRITECONFIG");
852 	if (env && *env) {
853 		*tmpname = 0;
854 		out = fopen(name, "w");
855 	} else {
856 		snprintf(tmpname, sizeof(tmpname), "%s.%d.tmp",
857 			 name, (int)getpid());
858 		out = fopen(tmpname, "w");
859 	}
860 	if (!out)
861 		return 1;
862 
863 	conf_write_heading(out, &kconfig_printer_cb, NULL);
864 
865 	if (!conf_get_changed())
866 		sym_clear_all_valid();
867 
868 	menu = rootmenu.list;
869 	while (menu) {
870 		sym = menu->sym;
871 		if (!sym) {
872 			if (!menu_is_visible(menu))
873 				goto next;
874 			str = menu_get_prompt(menu);
875 			fprintf(out, "\n"
876 				     "#\n"
877 				     "# %s\n"
878 				     "#\n", str);
879 			need_newline = false;
880 		} else if (!(sym->flags & SYMBOL_CHOICE) &&
881 			   !(sym->flags & SYMBOL_WRITTEN)) {
882 			sym_calc_value(sym);
883 			if (!(sym->flags & SYMBOL_WRITE))
884 				goto next;
885 			if (need_newline) {
886 				fprintf(out, "\n");
887 				need_newline = false;
888 			}
889 			sym->flags |= SYMBOL_WRITTEN;
890 			conf_write_symbol(out, sym, &kconfig_printer_cb, NULL);
891 		}
892 
893 next:
894 		if (menu->list) {
895 			menu = menu->list;
896 			continue;
897 		}
898 		if (menu->next)
899 			menu = menu->next;
900 		else while ((menu = menu->parent)) {
901 			if (!menu->sym && menu_is_visible(menu) &&
902 			    menu != &rootmenu) {
903 				str = menu_get_prompt(menu);
904 				fprintf(out, "# end of %s\n", str);
905 				need_newline = true;
906 			}
907 			if (menu->next) {
908 				menu = menu->next;
909 				break;
910 			}
911 		}
912 	}
913 	fclose(out);
914 
915 	for_all_symbols(i, sym)
916 		sym->flags &= ~SYMBOL_WRITTEN;
917 
918 	if (*tmpname) {
919 		if (is_same(name, tmpname)) {
920 			conf_message("No change to %s", name);
921 			unlink(tmpname);
922 			sym_set_change_count(0);
923 			return 0;
924 		}
925 
926 		snprintf(oldname, sizeof(oldname), "%s.old", name);
927 		rename(name, oldname);
928 		if (rename(tmpname, name))
929 			return 1;
930 	}
931 
932 	conf_message("configuration written to %s", name);
933 
934 	sym_set_change_count(0);
935 
936 	return 0;
937 }
938 
939 /* write a dependency file as used by kbuild to track dependencies */
940 static int conf_write_dep(const char *name)
941 {
942 	struct file *file;
943 	FILE *out;
944 
945 	out = fopen("..config.tmp", "w");
946 	if (!out)
947 		return 1;
948 	fprintf(out, "deps_config := \\\n");
949 	for (file = file_list; file; file = file->next) {
950 		if (file->next)
951 			fprintf(out, "\t%s \\\n", file->name);
952 		else
953 			fprintf(out, "\t%s\n", file->name);
954 	}
955 	fprintf(out, "\n%s: \\\n"
956 		     "\t$(deps_config)\n\n", conf_get_autoconfig_name());
957 
958 	env_write_dep(out, conf_get_autoconfig_name());
959 
960 	fprintf(out, "\n$(deps_config): ;\n");
961 	fclose(out);
962 
963 	if (make_parent_dir(name))
964 		return 1;
965 	rename("..config.tmp", name);
966 	return 0;
967 }
968 
969 static int conf_touch_deps(void)
970 {
971 	const char *name;
972 	struct symbol *sym;
973 	int res, i;
974 
975 	strcpy(depfile_path, "include/config/");
976 	depfile_prefix_len = strlen(depfile_path);
977 
978 	name = conf_get_autoconfig_name();
979 	conf_read_simple(name, S_DEF_AUTO);
980 	sym_calc_value(modules_sym);
981 
982 	for_all_symbols(i, sym) {
983 		sym_calc_value(sym);
984 		if ((sym->flags & SYMBOL_NO_WRITE) || !sym->name)
985 			continue;
986 		if (sym->flags & SYMBOL_WRITE) {
987 			if (sym->flags & SYMBOL_DEF_AUTO) {
988 				/*
989 				 * symbol has old and new value,
990 				 * so compare them...
991 				 */
992 				switch (sym->type) {
993 				case S_BOOLEAN:
994 				case S_TRISTATE:
995 					if (sym_get_tristate_value(sym) ==
996 					    sym->def[S_DEF_AUTO].tri)
997 						continue;
998 					break;
999 				case S_STRING:
1000 				case S_HEX:
1001 				case S_INT:
1002 					if (!strcmp(sym_get_string_value(sym),
1003 						    sym->def[S_DEF_AUTO].val))
1004 						continue;
1005 					break;
1006 				default:
1007 					break;
1008 				}
1009 			} else {
1010 				/*
1011 				 * If there is no old value, only 'no' (unset)
1012 				 * is allowed as new value.
1013 				 */
1014 				switch (sym->type) {
1015 				case S_BOOLEAN:
1016 				case S_TRISTATE:
1017 					if (sym_get_tristate_value(sym) == no)
1018 						continue;
1019 					break;
1020 				default:
1021 					break;
1022 				}
1023 			}
1024 		} else if (!(sym->flags & SYMBOL_DEF_AUTO))
1025 			/* There is neither an old nor a new value. */
1026 			continue;
1027 		/* else
1028 		 *	There is an old value, but no new value ('no' (unset)
1029 		 *	isn't saved in auto.conf, so the old value is always
1030 		 *	different from 'no').
1031 		 */
1032 
1033 		res = conf_touch_dep(sym->name);
1034 		if (res)
1035 			return res;
1036 	}
1037 
1038 	return 0;
1039 }
1040 
1041 int conf_write_autoconf(int overwrite)
1042 {
1043 	struct symbol *sym;
1044 	const char *name;
1045 	const char *autoconf_name = conf_get_autoconfig_name();
1046 	FILE *out, *out_h;
1047 	int i;
1048 
1049 	if (!overwrite && is_present(autoconf_name))
1050 		return 0;
1051 
1052 	conf_write_dep("include/config/auto.conf.cmd");
1053 
1054 	if (conf_touch_deps())
1055 		return 1;
1056 
1057 	out = fopen(".tmpconfig", "w");
1058 	if (!out)
1059 		return 1;
1060 
1061 	out_h = fopen(".tmpconfig.h", "w");
1062 	if (!out_h) {
1063 		fclose(out);
1064 		return 1;
1065 	}
1066 
1067 	conf_write_heading(out, &kconfig_printer_cb, NULL);
1068 	conf_write_heading(out_h, &header_printer_cb, NULL);
1069 
1070 	for_all_symbols(i, sym) {
1071 		sym_calc_value(sym);
1072 		if (!(sym->flags & SYMBOL_WRITE) || !sym->name)
1073 			continue;
1074 
1075 		/* write symbols to auto.conf and autoconf.h */
1076 		conf_write_symbol(out, sym, &kconfig_printer_cb, (void *)1);
1077 		conf_write_symbol(out_h, sym, &header_printer_cb, NULL);
1078 	}
1079 	fclose(out);
1080 	fclose(out_h);
1081 
1082 	name = getenv("KCONFIG_AUTOHEADER");
1083 	if (!name)
1084 		name = "include/generated/autoconf.h";
1085 	if (make_parent_dir(name))
1086 		return 1;
1087 	if (rename(".tmpconfig.h", name))
1088 		return 1;
1089 
1090 	if (make_parent_dir(autoconf_name))
1091 		return 1;
1092 	/*
1093 	 * This must be the last step, kbuild has a dependency on auto.conf
1094 	 * and this marks the successful completion of the previous steps.
1095 	 */
1096 	if (rename(".tmpconfig", autoconf_name))
1097 		return 1;
1098 
1099 	return 0;
1100 }
1101 
1102 static int sym_change_count;
1103 static void (*conf_changed_callback)(void);
1104 
1105 void sym_set_change_count(int count)
1106 {
1107 	int _sym_change_count = sym_change_count;
1108 	sym_change_count = count;
1109 	if (conf_changed_callback &&
1110 	    (bool)_sym_change_count != (bool)count)
1111 		conf_changed_callback();
1112 }
1113 
1114 void sym_add_change_count(int count)
1115 {
1116 	sym_set_change_count(count + sym_change_count);
1117 }
1118 
1119 bool conf_get_changed(void)
1120 {
1121 	return sym_change_count;
1122 }
1123 
1124 void conf_set_changed_callback(void (*fn)(void))
1125 {
1126 	conf_changed_callback = fn;
1127 }
1128 
1129 static bool randomize_choice_values(struct symbol *csym)
1130 {
1131 	struct property *prop;
1132 	struct symbol *sym;
1133 	struct expr *e;
1134 	int cnt, def;
1135 
1136 	/*
1137 	 * If choice is mod then we may have more items selected
1138 	 * and if no then no-one.
1139 	 * In both cases stop.
1140 	 */
1141 	if (csym->curr.tri != yes)
1142 		return false;
1143 
1144 	prop = sym_get_choice_prop(csym);
1145 
1146 	/* count entries in choice block */
1147 	cnt = 0;
1148 	expr_list_for_each_sym(prop->expr, e, sym)
1149 		cnt++;
1150 
1151 	/*
1152 	 * find a random value and set it to yes,
1153 	 * set the rest to no so we have only one set
1154 	 */
1155 	def = (rand() % cnt);
1156 
1157 	cnt = 0;
1158 	expr_list_for_each_sym(prop->expr, e, sym) {
1159 		if (def == cnt++) {
1160 			sym->def[S_DEF_USER].tri = yes;
1161 			csym->def[S_DEF_USER].val = sym;
1162 		}
1163 		else {
1164 			sym->def[S_DEF_USER].tri = no;
1165 		}
1166 		sym->flags |= SYMBOL_DEF_USER;
1167 		/* clear VALID to get value calculated */
1168 		sym->flags &= ~SYMBOL_VALID;
1169 	}
1170 	csym->flags |= SYMBOL_DEF_USER;
1171 	/* clear VALID to get value calculated */
1172 	csym->flags &= ~(SYMBOL_VALID);
1173 
1174 	return true;
1175 }
1176 
1177 void set_all_choice_values(struct symbol *csym)
1178 {
1179 	struct property *prop;
1180 	struct symbol *sym;
1181 	struct expr *e;
1182 
1183 	prop = sym_get_choice_prop(csym);
1184 
1185 	/*
1186 	 * Set all non-assinged choice values to no
1187 	 */
1188 	expr_list_for_each_sym(prop->expr, e, sym) {
1189 		if (!sym_has_value(sym))
1190 			sym->def[S_DEF_USER].tri = no;
1191 	}
1192 	csym->flags |= SYMBOL_DEF_USER;
1193 	/* clear VALID to get value calculated */
1194 	csym->flags &= ~(SYMBOL_VALID | SYMBOL_NEED_SET_CHOICE_VALUES);
1195 }
1196 
1197 bool conf_set_all_new_symbols(enum conf_def_mode mode)
1198 {
1199 	struct symbol *sym, *csym;
1200 	int i, cnt, pby, pty, ptm;	/* pby: probability of bool     = y
1201 					 * pty: probability of tristate = y
1202 					 * ptm: probability of tristate = m
1203 					 */
1204 
1205 	pby = 50; pty = ptm = 33; /* can't go as the default in switch-case
1206 				   * below, otherwise gcc whines about
1207 				   * -Wmaybe-uninitialized */
1208 	if (mode == def_random) {
1209 		int n, p[3];
1210 		char *env = getenv("KCONFIG_PROBABILITY");
1211 		n = 0;
1212 		while( env && *env ) {
1213 			char *endp;
1214 			int tmp = strtol( env, &endp, 10 );
1215 			if( tmp >= 0 && tmp <= 100 ) {
1216 				p[n++] = tmp;
1217 			} else {
1218 				errno = ERANGE;
1219 				perror( "KCONFIG_PROBABILITY" );
1220 				exit( 1 );
1221 			}
1222 			env = (*endp == ':') ? endp+1 : endp;
1223 			if( n >=3 ) {
1224 				break;
1225 			}
1226 		}
1227 		switch( n ) {
1228 		case 1:
1229 			pby = p[0]; ptm = pby/2; pty = pby-ptm;
1230 			break;
1231 		case 2:
1232 			pty = p[0]; ptm = p[1]; pby = pty + ptm;
1233 			break;
1234 		case 3:
1235 			pby = p[0]; pty = p[1]; ptm = p[2];
1236 			break;
1237 		}
1238 
1239 		if( pty+ptm > 100 ) {
1240 			errno = ERANGE;
1241 			perror( "KCONFIG_PROBABILITY" );
1242 			exit( 1 );
1243 		}
1244 	}
1245 	bool has_changed = false;
1246 
1247 	for_all_symbols(i, sym) {
1248 		if (sym_has_value(sym) || (sym->flags & SYMBOL_VALID))
1249 			continue;
1250 		switch (sym_get_type(sym)) {
1251 		case S_BOOLEAN:
1252 		case S_TRISTATE:
1253 			has_changed = true;
1254 			switch (mode) {
1255 			case def_yes:
1256 				sym->def[S_DEF_USER].tri = yes;
1257 				break;
1258 			case def_mod:
1259 				sym->def[S_DEF_USER].tri = mod;
1260 				break;
1261 			case def_no:
1262 				if (sym->flags & SYMBOL_ALLNOCONFIG_Y)
1263 					sym->def[S_DEF_USER].tri = yes;
1264 				else
1265 					sym->def[S_DEF_USER].tri = no;
1266 				break;
1267 			case def_random:
1268 				sym->def[S_DEF_USER].tri = no;
1269 				cnt = rand() % 100;
1270 				if (sym->type == S_TRISTATE) {
1271 					if (cnt < pty)
1272 						sym->def[S_DEF_USER].tri = yes;
1273 					else if (cnt < (pty+ptm))
1274 						sym->def[S_DEF_USER].tri = mod;
1275 				} else if (cnt < pby)
1276 					sym->def[S_DEF_USER].tri = yes;
1277 				break;
1278 			default:
1279 				continue;
1280 			}
1281 			if (!(sym_is_choice(sym) && mode == def_random))
1282 				sym->flags |= SYMBOL_DEF_USER;
1283 			break;
1284 		default:
1285 			break;
1286 		}
1287 
1288 	}
1289 
1290 	sym_clear_all_valid();
1291 
1292 	/*
1293 	 * We have different type of choice blocks.
1294 	 * If curr.tri equals to mod then we can select several
1295 	 * choice symbols in one block.
1296 	 * In this case we do nothing.
1297 	 * If curr.tri equals yes then only one symbol can be
1298 	 * selected in a choice block and we set it to yes,
1299 	 * and the rest to no.
1300 	 */
1301 	if (mode != def_random) {
1302 		for_all_symbols(i, csym) {
1303 			if ((sym_is_choice(csym) && !sym_has_value(csym)) ||
1304 			    sym_is_choice_value(csym))
1305 				csym->flags |= SYMBOL_NEED_SET_CHOICE_VALUES;
1306 		}
1307 	}
1308 
1309 	for_all_symbols(i, csym) {
1310 		if (sym_has_value(csym) || !sym_is_choice(csym))
1311 			continue;
1312 
1313 		sym_calc_value(csym);
1314 		if (mode == def_random)
1315 			has_changed |= randomize_choice_values(csym);
1316 		else {
1317 			set_all_choice_values(csym);
1318 			has_changed = true;
1319 		}
1320 	}
1321 
1322 	return has_changed;
1323 }
1324 
1325 void conf_rewrite_mod_or_yes(enum conf_def_mode mode)
1326 {
1327 	struct symbol *sym;
1328 	int i;
1329 	tristate old_val = (mode == def_y2m) ? yes : mod;
1330 	tristate new_val = (mode == def_y2m) ? mod : yes;
1331 
1332 	for_all_symbols(i, sym) {
1333 		if (sym_get_type(sym) == S_TRISTATE &&
1334 		    sym->def[S_DEF_USER].tri == old_val)
1335 			sym->def[S_DEF_USER].tri = new_val;
1336 	}
1337 	sym_clear_all_valid();
1338 }
1339