1/*
2 * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
3 * Released under the terms of the GNU GPL v2.0.
4 */
5
6#include <ctype.h>
7#include <stdlib.h>
8#include <string.h>
9#include <regex.h>
10#include <sys/utsname.h>
11
12#include "lkc.h"
13
14struct symbol symbol_yes = {
15	.name = "y",
16	.curr = { "y", yes },
17	.flags = SYMBOL_CONST|SYMBOL_VALID,
18}, symbol_mod = {
19	.name = "m",
20	.curr = { "m", mod },
21	.flags = SYMBOL_CONST|SYMBOL_VALID,
22}, symbol_no = {
23	.name = "n",
24	.curr = { "n", no },
25	.flags = SYMBOL_CONST|SYMBOL_VALID,
26}, symbol_empty = {
27	.name = "",
28	.curr = { "", no },
29	.flags = SYMBOL_VALID,
30};
31
32struct symbol *sym_defconfig_list;
33struct symbol *modules_sym;
34tristate modules_val;
35
36struct expr *sym_env_list;
37
38static void sym_add_default(struct symbol *sym, const char *def)
39{
40	struct property *prop = prop_alloc(P_DEFAULT, sym);
41
42	prop->expr = expr_alloc_symbol(sym_lookup(def, SYMBOL_CONST));
43}
44
45void sym_init(void)
46{
47	struct symbol *sym;
48	struct utsname uts;
49	static bool inited = false;
50
51	if (inited)
52		return;
53	inited = true;
54
55	uname(&uts);
56
57	sym = sym_lookup("UNAME_RELEASE", 0);
58	sym->type = S_STRING;
59	sym->flags |= SYMBOL_AUTO;
60	sym_add_default(sym, uts.release);
61}
62
63enum symbol_type sym_get_type(struct symbol *sym)
64{
65	enum symbol_type type = sym->type;
66
67	if (type == S_TRISTATE) {
68		if (sym_is_choice_value(sym) && sym->visible == yes)
69			type = S_BOOLEAN;
70		else if (modules_val == no)
71			type = S_BOOLEAN;
72	}
73	return type;
74}
75
76const char *sym_type_name(enum symbol_type type)
77{
78	switch (type) {
79	case S_BOOLEAN:
80		return "boolean";
81	case S_TRISTATE:
82		return "tristate";
83	case S_INT:
84		return "integer";
85	case S_HEX:
86		return "hex";
87	case S_STRING:
88		return "string";
89	case S_UNKNOWN:
90		return "unknown";
91	case S_OTHER:
92		break;
93	}
94	return "???";
95}
96
97struct property *sym_get_choice_prop(struct symbol *sym)
98{
99	struct property *prop;
100
101	for_all_choices(sym, prop)
102		return prop;
103	return NULL;
104}
105
106struct property *sym_get_env_prop(struct symbol *sym)
107{
108	struct property *prop;
109
110	for_all_properties(sym, prop, P_ENV)
111		return prop;
112	return NULL;
113}
114
115static struct property *sym_get_default_prop(struct symbol *sym)
116{
117	struct property *prop;
118
119	for_all_defaults(sym, prop) {
120		prop->visible.tri = expr_calc_value(prop->visible.expr);
121		if (prop->visible.tri != no)
122			return prop;
123	}
124	return NULL;
125}
126
127static struct property *sym_get_range_prop(struct symbol *sym)
128{
129	struct property *prop;
130
131	for_all_properties(sym, prop, P_RANGE) {
132		prop->visible.tri = expr_calc_value(prop->visible.expr);
133		if (prop->visible.tri != no)
134			return prop;
135	}
136	return NULL;
137}
138
139static long long sym_get_range_val(struct symbol *sym, int base)
140{
141	sym_calc_value(sym);
142	switch (sym->type) {
143	case S_INT:
144		base = 10;
145		break;
146	case S_HEX:
147		base = 16;
148		break;
149	default:
150		break;
151	}
152	return strtoll(sym->curr.val, NULL, base);
153}
154
155static void sym_validate_range(struct symbol *sym)
156{
157	struct property *prop;
158	int base;
159	long long val, val2;
160	char str[64];
161
162	switch (sym->type) {
163	case S_INT:
164		base = 10;
165		break;
166	case S_HEX:
167		base = 16;
168		break;
169	default:
170		return;
171	}
172	prop = sym_get_range_prop(sym);
173	if (!prop)
174		return;
175	val = strtoll(sym->curr.val, NULL, base);
176	val2 = sym_get_range_val(prop->expr->left.sym, base);
177	if (val >= val2) {
178		val2 = sym_get_range_val(prop->expr->right.sym, base);
179		if (val <= val2)
180			return;
181	}
182	if (sym->type == S_INT)
183		sprintf(str, "%lld", val2);
184	else
185		sprintf(str, "0x%llx", val2);
186	sym->curr.val = strdup(str);
187}
188
189static void sym_set_changed(struct symbol *sym)
190{
191	struct property *prop;
192
193	sym->flags |= SYMBOL_CHANGED;
194	for (prop = sym->prop; prop; prop = prop->next) {
195		if (prop->menu)
196			prop->menu->flags |= MENU_CHANGED;
197	}
198}
199
200static void sym_set_all_changed(void)
201{
202	struct symbol *sym;
203	int i;
204
205	for_all_symbols(i, sym)
206		sym_set_changed(sym);
207}
208
209static void sym_calc_visibility(struct symbol *sym)
210{
211	struct property *prop;
212	tristate tri;
213
214	/* any prompt visible? */
215	tri = no;
216	for_all_prompts(sym, prop) {
217		prop->visible.tri = expr_calc_value(prop->visible.expr);
218		tri = EXPR_OR(tri, prop->visible.tri);
219	}
220	if (tri == mod && (sym->type != S_TRISTATE || modules_val == no))
221		tri = yes;
222	if (sym->visible != tri) {
223		sym->visible = tri;
224		sym_set_changed(sym);
225	}
226	if (sym_is_choice_value(sym))
227		return;
228	/* defaulting to "yes" if no explicit "depends on" are given */
229	tri = yes;
230	if (sym->dir_dep.expr)
231		tri = expr_calc_value(sym->dir_dep.expr);
232	if (tri == mod)
233		tri = yes;
234	if (sym->dir_dep.tri != tri) {
235		sym->dir_dep.tri = tri;
236		sym_set_changed(sym);
237	}
238	tri = no;
239	if (sym->rev_dep.expr)
240		tri = expr_calc_value(sym->rev_dep.expr);
241	if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
242		tri = yes;
243	if (sym->rev_dep.tri != tri) {
244		sym->rev_dep.tri = tri;
245		sym_set_changed(sym);
246	}
247}
248
249/*
250 * Find the default symbol for a choice.
251 * First try the default values for the choice symbol
252 * Next locate the first visible choice value
253 * Return NULL if none was found
254 */
255struct symbol *sym_choice_default(struct symbol *sym)
256{
257	struct symbol *def_sym;
258	struct property *prop;
259	struct expr *e;
260
261	/* any of the defaults visible? */
262	for_all_defaults(sym, prop) {
263		prop->visible.tri = expr_calc_value(prop->visible.expr);
264		if (prop->visible.tri == no)
265			continue;
266		def_sym = prop_get_symbol(prop);
267		if (def_sym->visible != no)
268			return def_sym;
269	}
270
271	/* just get the first visible value */
272	prop = sym_get_choice_prop(sym);
273	expr_list_for_each_sym(prop->expr, e, def_sym)
274		if (def_sym->visible != no)
275			return def_sym;
276
277	/* failed to locate any defaults */
278	return NULL;
279}
280
281static struct symbol *sym_calc_choice(struct symbol *sym)
282{
283	struct symbol *def_sym;
284	struct property *prop;
285	struct expr *e;
286	int flags;
287
288	/* first calculate all choice values' visibilities */
289	flags = sym->flags;
290	prop = sym_get_choice_prop(sym);
291	expr_list_for_each_sym(prop->expr, e, def_sym) {
292		sym_calc_visibility(def_sym);
293		if (def_sym->visible != no)
294			flags &= def_sym->flags;
295	}
296
297	sym->flags &= flags | ~SYMBOL_DEF_USER;
298
299	/* is the user choice visible? */
300	def_sym = sym->def[S_DEF_USER].val;
301	if (def_sym && def_sym->visible != no)
302		return def_sym;
303
304	def_sym = sym_choice_default(sym);
305
306	if (def_sym == NULL)
307		/* no choice? reset tristate value */
308		sym->curr.tri = no;
309
310	return def_sym;
311}
312
313void sym_calc_value(struct symbol *sym)
314{
315	struct symbol_value newval, oldval;
316	struct property *prop;
317	struct expr *e;
318
319	if (!sym)
320		return;
321
322	if (sym->flags & SYMBOL_VALID)
323		return;
324
325	if (sym_is_choice_value(sym) &&
326	    sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES) {
327		sym->flags &= ~SYMBOL_NEED_SET_CHOICE_VALUES;
328		prop = sym_get_choice_prop(sym);
329		sym_calc_value(prop_get_symbol(prop));
330	}
331
332	sym->flags |= SYMBOL_VALID;
333
334	oldval = sym->curr;
335
336	switch (sym->type) {
337	case S_INT:
338	case S_HEX:
339	case S_STRING:
340		newval = symbol_empty.curr;
341		break;
342	case S_BOOLEAN:
343	case S_TRISTATE:
344		newval = symbol_no.curr;
345		break;
346	default:
347		sym->curr.val = sym->name;
348		sym->curr.tri = no;
349		return;
350	}
351	if (!sym_is_choice_value(sym))
352		sym->flags &= ~SYMBOL_WRITE;
353
354	sym_calc_visibility(sym);
355
356	/* set default if recursively called */
357	sym->curr = newval;
358
359	switch (sym_get_type(sym)) {
360	case S_BOOLEAN:
361	case S_TRISTATE:
362		if (sym_is_choice_value(sym) && sym->visible == yes) {
363			prop = sym_get_choice_prop(sym);
364			newval.tri = (prop_get_symbol(prop)->curr.val == sym) ? yes : no;
365		} else {
366			if (sym->visible != no) {
367				/* if the symbol is visible use the user value
368				 * if available, otherwise try the default value
369				 */
370				sym->flags |= SYMBOL_WRITE;
371				if (sym_has_value(sym)) {
372					newval.tri = EXPR_AND(sym->def[S_DEF_USER].tri,
373							      sym->visible);
374					goto calc_newval;
375				}
376			}
377			if (sym->rev_dep.tri != no)
378				sym->flags |= SYMBOL_WRITE;
379			if (!sym_is_choice(sym)) {
380				prop = sym_get_default_prop(sym);
381				if (prop) {
382					sym->flags |= SYMBOL_WRITE;
383					newval.tri = EXPR_AND(expr_calc_value(prop->expr),
384							      prop->visible.tri);
385				}
386			}
387		calc_newval:
388			if (sym->dir_dep.tri == no && sym->rev_dep.tri != no) {
389				struct expr *e;
390				e = expr_simplify_unmet_dep(sym->rev_dep.expr,
391				    sym->dir_dep.expr);
392				fprintf(stderr, "warning: (");
393				expr_fprint(e, stderr);
394				fprintf(stderr, ") selects %s which has unmet direct dependencies (",
395					sym->name);
396				expr_fprint(sym->dir_dep.expr, stderr);
397				fprintf(stderr, ")\n");
398				expr_free(e);
399			}
400			newval.tri = EXPR_OR(newval.tri, sym->rev_dep.tri);
401		}
402		if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
403			newval.tri = yes;
404		break;
405	case S_STRING:
406	case S_HEX:
407	case S_INT:
408		if (sym->visible != no) {
409			sym->flags |= SYMBOL_WRITE;
410			if (sym_has_value(sym)) {
411				newval.val = sym->def[S_DEF_USER].val;
412				break;
413			}
414		}
415		prop = sym_get_default_prop(sym);
416		if (prop) {
417			struct symbol *ds = prop_get_symbol(prop);
418			if (ds) {
419				sym->flags |= SYMBOL_WRITE;
420				sym_calc_value(ds);
421				newval.val = ds->curr.val;
422			}
423		}
424		break;
425	default:
426		;
427	}
428
429	sym->curr = newval;
430	if (sym_is_choice(sym) && newval.tri == yes)
431		sym->curr.val = sym_calc_choice(sym);
432	sym_validate_range(sym);
433
434	if (memcmp(&oldval, &sym->curr, sizeof(oldval))) {
435		sym_set_changed(sym);
436		if (modules_sym == sym) {
437			sym_set_all_changed();
438			modules_val = modules_sym->curr.tri;
439		}
440	}
441
442	if (sym_is_choice(sym)) {
443		struct symbol *choice_sym;
444
445		prop = sym_get_choice_prop(sym);
446		expr_list_for_each_sym(prop->expr, e, choice_sym) {
447			if ((sym->flags & SYMBOL_WRITE) &&
448			    choice_sym->visible != no)
449				choice_sym->flags |= SYMBOL_WRITE;
450			if (sym->flags & SYMBOL_CHANGED)
451				sym_set_changed(choice_sym);
452		}
453	}
454
455	if (sym->flags & SYMBOL_AUTO)
456		sym->flags &= ~SYMBOL_WRITE;
457
458	if (sym->flags & SYMBOL_NEED_SET_CHOICE_VALUES)
459		set_all_choice_values(sym);
460}
461
462void sym_clear_all_valid(void)
463{
464	struct symbol *sym;
465	int i;
466
467	for_all_symbols(i, sym)
468		sym->flags &= ~SYMBOL_VALID;
469	sym_add_change_count(1);
470	sym_calc_value(modules_sym);
471}
472
473bool sym_tristate_within_range(struct symbol *sym, tristate val)
474{
475	int type = sym_get_type(sym);
476
477	if (sym->visible == no)
478		return false;
479
480	if (type != S_BOOLEAN && type != S_TRISTATE)
481		return false;
482
483	if (type == S_BOOLEAN && val == mod)
484		return false;
485	if (sym->visible <= sym->rev_dep.tri)
486		return false;
487	if (sym_is_choice_value(sym) && sym->visible == yes)
488		return val == yes;
489	return val >= sym->rev_dep.tri && val <= sym->visible;
490}
491
492bool sym_set_tristate_value(struct symbol *sym, tristate val)
493{
494	tristate oldval = sym_get_tristate_value(sym);
495
496	if (oldval != val && !sym_tristate_within_range(sym, val))
497		return false;
498
499	if (!(sym->flags & SYMBOL_DEF_USER)) {
500		sym->flags |= SYMBOL_DEF_USER;
501		sym_set_changed(sym);
502	}
503	/*
504	 * setting a choice value also resets the new flag of the choice
505	 * symbol and all other choice values.
506	 */
507	if (sym_is_choice_value(sym) && val == yes) {
508		struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
509		struct property *prop;
510		struct expr *e;
511
512		cs->def[S_DEF_USER].val = sym;
513		cs->flags |= SYMBOL_DEF_USER;
514		prop = sym_get_choice_prop(cs);
515		for (e = prop->expr; e; e = e->left.expr) {
516			if (e->right.sym->visible != no)
517				e->right.sym->flags |= SYMBOL_DEF_USER;
518		}
519	}
520
521	sym->def[S_DEF_USER].tri = val;
522	if (oldval != val)
523		sym_clear_all_valid();
524
525	return true;
526}
527
528tristate sym_toggle_tristate_value(struct symbol *sym)
529{
530	tristate oldval, newval;
531
532	oldval = newval = sym_get_tristate_value(sym);
533	do {
534		switch (newval) {
535		case no:
536			newval = mod;
537			break;
538		case mod:
539			newval = yes;
540			break;
541		case yes:
542			newval = no;
543			break;
544		}
545		if (sym_set_tristate_value(sym, newval))
546			break;
547	} while (oldval != newval);
548	return newval;
549}
550
551bool sym_string_valid(struct symbol *sym, const char *str)
552{
553	signed char ch;
554
555	switch (sym->type) {
556	case S_STRING:
557		return true;
558	case S_INT:
559		ch = *str++;
560		if (ch == '-')
561			ch = *str++;
562		if (!isdigit(ch))
563			return false;
564		if (ch == '0' && *str != 0)
565			return false;
566		while ((ch = *str++)) {
567			if (!isdigit(ch))
568				return false;
569		}
570		return true;
571	case S_HEX:
572		if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
573			str += 2;
574		ch = *str++;
575		do {
576			if (!isxdigit(ch))
577				return false;
578		} while ((ch = *str++));
579		return true;
580	case S_BOOLEAN:
581	case S_TRISTATE:
582		switch (str[0]) {
583		case 'y': case 'Y':
584		case 'm': case 'M':
585		case 'n': case 'N':
586			return true;
587		}
588		return false;
589	default:
590		return false;
591	}
592}
593
594bool sym_string_within_range(struct symbol *sym, const char *str)
595{
596	struct property *prop;
597	long long val;
598
599	switch (sym->type) {
600	case S_STRING:
601		return sym_string_valid(sym, str);
602	case S_INT:
603		if (!sym_string_valid(sym, str))
604			return false;
605		prop = sym_get_range_prop(sym);
606		if (!prop)
607			return true;
608		val = strtoll(str, NULL, 10);
609		return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
610		       val <= sym_get_range_val(prop->expr->right.sym, 10);
611	case S_HEX:
612		if (!sym_string_valid(sym, str))
613			return false;
614		prop = sym_get_range_prop(sym);
615		if (!prop)
616			return true;
617		val = strtoll(str, NULL, 16);
618		return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
619		       val <= sym_get_range_val(prop->expr->right.sym, 16);
620	case S_BOOLEAN:
621	case S_TRISTATE:
622		switch (str[0]) {
623		case 'y': case 'Y':
624			return sym_tristate_within_range(sym, yes);
625		case 'm': case 'M':
626			return sym_tristate_within_range(sym, mod);
627		case 'n': case 'N':
628			return sym_tristate_within_range(sym, no);
629		}
630		return false;
631	default:
632		return false;
633	}
634}
635
636bool sym_set_string_value(struct symbol *sym, const char *newval)
637{
638	const char *oldval;
639	char *val;
640	int size;
641
642	switch (sym->type) {
643	case S_BOOLEAN:
644	case S_TRISTATE:
645		switch (newval[0]) {
646		case 'y': case 'Y':
647			return sym_set_tristate_value(sym, yes);
648		case 'm': case 'M':
649			return sym_set_tristate_value(sym, mod);
650		case 'n': case 'N':
651			return sym_set_tristate_value(sym, no);
652		}
653		return false;
654	default:
655		;
656	}
657
658	if (!sym_string_within_range(sym, newval))
659		return false;
660
661	if (!(sym->flags & SYMBOL_DEF_USER)) {
662		sym->flags |= SYMBOL_DEF_USER;
663		sym_set_changed(sym);
664	}
665
666	oldval = sym->def[S_DEF_USER].val;
667	size = strlen(newval) + 1;
668	if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
669		size += 2;
670		sym->def[S_DEF_USER].val = val = xmalloc(size);
671		*val++ = '0';
672		*val++ = 'x';
673	} else if (!oldval || strcmp(oldval, newval))
674		sym->def[S_DEF_USER].val = val = xmalloc(size);
675	else
676		return true;
677
678	strcpy(val, newval);
679	free((void *)oldval);
680	sym_clear_all_valid();
681
682	return true;
683}
684
685/*
686 * Find the default value associated to a symbol.
687 * For tristate symbol handle the modules=n case
688 * in which case "m" becomes "y".
689 * If the symbol does not have any default then fallback
690 * to the fixed default values.
691 */
692const char *sym_get_string_default(struct symbol *sym)
693{
694	struct property *prop;
695	struct symbol *ds;
696	const char *str;
697	tristate val;
698
699	sym_calc_visibility(sym);
700	sym_calc_value(modules_sym);
701	val = symbol_no.curr.tri;
702	str = symbol_empty.curr.val;
703
704	/* If symbol has a default value look it up */
705	prop = sym_get_default_prop(sym);
706	if (prop != NULL) {
707		switch (sym->type) {
708		case S_BOOLEAN:
709		case S_TRISTATE:
710			/* The visibility may limit the value from yes => mod */
711			val = EXPR_AND(expr_calc_value(prop->expr), prop->visible.tri);
712			break;
713		default:
714			/*
715			 * The following fails to handle the situation
716			 * where a default value is further limited by
717			 * the valid range.
718			 */
719			ds = prop_get_symbol(prop);
720			if (ds != NULL) {
721				sym_calc_value(ds);
722				str = (const char *)ds->curr.val;
723			}
724		}
725	}
726
727	/* Handle select statements */
728	val = EXPR_OR(val, sym->rev_dep.tri);
729
730	/* transpose mod to yes if modules are not enabled */
731	if (val == mod)
732		if (!sym_is_choice_value(sym) && modules_sym->curr.tri == no)
733			val = yes;
734
735	/* transpose mod to yes if type is bool */
736	if (sym->type == S_BOOLEAN && val == mod)
737		val = yes;
738
739	switch (sym->type) {
740	case S_BOOLEAN:
741	case S_TRISTATE:
742		switch (val) {
743		case no: return "n";
744		case mod: return "m";
745		case yes: return "y";
746		}
747	case S_INT:
748	case S_HEX:
749		return str;
750	case S_STRING:
751		return str;
752	case S_OTHER:
753	case S_UNKNOWN:
754		break;
755	}
756	return "";
757}
758
759const char *sym_get_string_value(struct symbol *sym)
760{
761	tristate val;
762
763	switch (sym->type) {
764	case S_BOOLEAN:
765	case S_TRISTATE:
766		val = sym_get_tristate_value(sym);
767		switch (val) {
768		case no:
769			return "n";
770		case mod:
771			sym_calc_value(modules_sym);
772			return (modules_sym->curr.tri == no) ? "n" : "m";
773		case yes:
774			return "y";
775		}
776		break;
777	default:
778		;
779	}
780	return (const char *)sym->curr.val;
781}
782
783bool sym_is_changable(struct symbol *sym)
784{
785	return sym->visible > sym->rev_dep.tri;
786}
787
788static unsigned strhash(const char *s)
789{
790	/* fnv32 hash */
791	unsigned hash = 2166136261U;
792	for (; *s; s++)
793		hash = (hash ^ *s) * 0x01000193;
794	return hash;
795}
796
797struct symbol *sym_lookup(const char *name, int flags)
798{
799	struct symbol *symbol;
800	char *new_name;
801	int hash;
802
803	if (name) {
804		if (name[0] && !name[1]) {
805			switch (name[0]) {
806			case 'y': return &symbol_yes;
807			case 'm': return &symbol_mod;
808			case 'n': return &symbol_no;
809			}
810		}
811		hash = strhash(name) % SYMBOL_HASHSIZE;
812
813		for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
814			if (symbol->name &&
815			    !strcmp(symbol->name, name) &&
816			    (flags ? symbol->flags & flags
817				   : !(symbol->flags & (SYMBOL_CONST|SYMBOL_CHOICE))))
818				return symbol;
819		}
820		new_name = strdup(name);
821	} else {
822		new_name = NULL;
823		hash = 0;
824	}
825
826	symbol = xmalloc(sizeof(*symbol));
827	memset(symbol, 0, sizeof(*symbol));
828	symbol->name = new_name;
829	symbol->type = S_UNKNOWN;
830	symbol->flags |= flags;
831
832	symbol->next = symbol_hash[hash];
833	symbol_hash[hash] = symbol;
834
835	return symbol;
836}
837
838struct symbol *sym_find(const char *name)
839{
840	struct symbol *symbol = NULL;
841	int hash = 0;
842
843	if (!name)
844		return NULL;
845
846	if (name[0] && !name[1]) {
847		switch (name[0]) {
848		case 'y': return &symbol_yes;
849		case 'm': return &symbol_mod;
850		case 'n': return &symbol_no;
851		}
852	}
853	hash = strhash(name) % SYMBOL_HASHSIZE;
854
855	for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
856		if (symbol->name &&
857		    !strcmp(symbol->name, name) &&
858		    !(symbol->flags & SYMBOL_CONST))
859				break;
860	}
861
862	return symbol;
863}
864
865/*
866 * Expand symbol's names embedded in the string given in argument. Symbols'
867 * name to be expanded shall be prefixed by a '$'. Unknown symbol expands to
868 * the empty string.
869 */
870const char *sym_expand_string_value(const char *in)
871{
872	const char *src;
873	char *res;
874	size_t reslen;
875
876	reslen = strlen(in) + 1;
877	res = xmalloc(reslen);
878	res[0] = '\0';
879
880	while ((src = strchr(in, '$'))) {
881		char *p, name[SYMBOL_MAXLENGTH];
882		const char *symval = "";
883		struct symbol *sym;
884		size_t newlen;
885
886		strncat(res, in, src - in);
887		src++;
888
889		p = name;
890		while (isalnum(*src) || *src == '_')
891			*p++ = *src++;
892		*p = '\0';
893
894		sym = sym_find(name);
895		if (sym != NULL) {
896			sym_calc_value(sym);
897			symval = sym_get_string_value(sym);
898		}
899
900		newlen = strlen(res) + strlen(symval) + strlen(src) + 1;
901		if (newlen > reslen) {
902			reslen = newlen;
903			res = realloc(res, reslen);
904		}
905
906		strcat(res, symval);
907		in = src;
908	}
909	strcat(res, in);
910
911	return res;
912}
913
914const char *sym_escape_string_value(const char *in)
915{
916	const char *p;
917	size_t reslen;
918	char *res;
919	size_t l;
920
921	reslen = strlen(in) + strlen("\"\"") + 1;
922
923	p = in;
924	for (;;) {
925		l = strcspn(p, "\"\\");
926		p += l;
927
928		if (p[0] == '\0')
929			break;
930
931		reslen++;
932		p++;
933	}
934
935	res = xmalloc(reslen);
936	res[0] = '\0';
937
938	strcat(res, "\"");
939
940	p = in;
941	for (;;) {
942		l = strcspn(p, "\"\\");
943		strncat(res, p, l);
944		p += l;
945
946		if (p[0] == '\0')
947			break;
948
949		strcat(res, "\\");
950		strncat(res, p++, 1);
951	}
952
953	strcat(res, "\"");
954	return res;
955}
956
957struct sym_match {
958	struct symbol	*sym;
959	off_t		so, eo;
960};
961
962/* Compare matched symbols as thus:
963 * - first, symbols that match exactly
964 * - then, alphabetical sort
965 */
966static int sym_rel_comp(const void *sym1, const void *sym2)
967{
968	const struct sym_match *s1 = sym1;
969	const struct sym_match *s2 = sym2;
970	int exact1, exact2;
971
972	/* Exact match:
973	 * - if matched length on symbol s1 is the length of that symbol,
974	 *   then this symbol should come first;
975	 * - if matched length on symbol s2 is the length of that symbol,
976	 *   then this symbol should come first.
977	 * Note: since the search can be a regexp, both symbols may match
978	 * exactly; if this is the case, we can't decide which comes first,
979	 * and we fallback to sorting alphabetically.
980	 */
981	exact1 = (s1->eo - s1->so) == strlen(s1->sym->name);
982	exact2 = (s2->eo - s2->so) == strlen(s2->sym->name);
983	if (exact1 && !exact2)
984		return -1;
985	if (!exact1 && exact2)
986		return 1;
987
988	/* As a fallback, sort symbols alphabetically */
989	return strcmp(s1->sym->name, s2->sym->name);
990}
991
992struct symbol **sym_re_search(const char *pattern)
993{
994	struct symbol *sym, **sym_arr = NULL;
995	struct sym_match *sym_match_arr = NULL;
996	int i, cnt, size;
997	regex_t re;
998	regmatch_t match[1];
999
1000	cnt = size = 0;
1001	/* Skip if empty */
1002	if (strlen(pattern) == 0)
1003		return NULL;
1004	if (regcomp(&re, pattern, REG_EXTENDED|REG_ICASE))
1005		return NULL;
1006
1007	for_all_symbols(i, sym) {
1008		if (sym->flags & SYMBOL_CONST || !sym->name)
1009			continue;
1010		if (regexec(&re, sym->name, 1, match, 0))
1011			continue;
1012		if (cnt >= size) {
1013			void *tmp;
1014			size += 16;
1015			tmp = realloc(sym_match_arr, size * sizeof(struct sym_match));
1016			if (!tmp)
1017				goto sym_re_search_free;
1018			sym_match_arr = tmp;
1019		}
1020		sym_calc_value(sym);
1021		/* As regexec returned 0, we know we have a match, so
1022		 * we can use match[0].rm_[se]o without further checks
1023		 */
1024		sym_match_arr[cnt].so = match[0].rm_so;
1025		sym_match_arr[cnt].eo = match[0].rm_eo;
1026		sym_match_arr[cnt++].sym = sym;
1027	}
1028	if (sym_match_arr) {
1029		qsort(sym_match_arr, cnt, sizeof(struct sym_match), sym_rel_comp);
1030		sym_arr = malloc((cnt+1) * sizeof(struct symbol));
1031		if (!sym_arr)
1032			goto sym_re_search_free;
1033		for (i = 0; i < cnt; i++)
1034			sym_arr[i] = sym_match_arr[i].sym;
1035		sym_arr[cnt] = NULL;
1036	}
1037sym_re_search_free:
1038	/* sym_match_arr can be NULL if no match, but free(NULL) is OK */
1039	free(sym_match_arr);
1040	regfree(&re);
1041
1042	return sym_arr;
1043}
1044
1045/*
1046 * When we check for recursive dependencies we use a stack to save
1047 * current state so we can print out relevant info to user.
1048 * The entries are located on the call stack so no need to free memory.
1049 * Note insert() remove() must always match to properly clear the stack.
1050 */
1051static struct dep_stack {
1052	struct dep_stack *prev, *next;
1053	struct symbol *sym;
1054	struct property *prop;
1055	struct expr *expr;
1056} *check_top;
1057
1058static void dep_stack_insert(struct dep_stack *stack, struct symbol *sym)
1059{
1060	memset(stack, 0, sizeof(*stack));
1061	if (check_top)
1062		check_top->next = stack;
1063	stack->prev = check_top;
1064	stack->sym = sym;
1065	check_top = stack;
1066}
1067
1068static void dep_stack_remove(void)
1069{
1070	check_top = check_top->prev;
1071	if (check_top)
1072		check_top->next = NULL;
1073}
1074
1075/*
1076 * Called when we have detected a recursive dependency.
1077 * check_top point to the top of the stact so we use
1078 * the ->prev pointer to locate the bottom of the stack.
1079 */
1080static void sym_check_print_recursive(struct symbol *last_sym)
1081{
1082	struct dep_stack *stack;
1083	struct symbol *sym, *next_sym;
1084	struct menu *menu = NULL;
1085	struct property *prop;
1086	struct dep_stack cv_stack;
1087
1088	if (sym_is_choice_value(last_sym)) {
1089		dep_stack_insert(&cv_stack, last_sym);
1090		last_sym = prop_get_symbol(sym_get_choice_prop(last_sym));
1091	}
1092
1093	for (stack = check_top; stack != NULL; stack = stack->prev)
1094		if (stack->sym == last_sym)
1095			break;
1096	if (!stack) {
1097		fprintf(stderr, "unexpected recursive dependency error\n");
1098		return;
1099	}
1100
1101	for (; stack; stack = stack->next) {
1102		sym = stack->sym;
1103		next_sym = stack->next ? stack->next->sym : last_sym;
1104		prop = stack->prop;
1105		if (prop == NULL)
1106			prop = stack->sym->prop;
1107
1108		/* for choice values find the menu entry (used below) */
1109		if (sym_is_choice(sym) || sym_is_choice_value(sym)) {
1110			for (prop = sym->prop; prop; prop = prop->next) {
1111				menu = prop->menu;
1112				if (prop->menu)
1113					break;
1114			}
1115		}
1116		if (stack->sym == last_sym)
1117			fprintf(stderr, "%s:%d:error: recursive dependency detected!\n",
1118				prop->file->name, prop->lineno);
1119			fprintf(stderr, "For a resolution refer to Documentation/kbuild/kconfig-language.txt\n");
1120			fprintf(stderr, "subsection \"Kconfig recursive dependency limitations\"\n");
1121		if (stack->expr) {
1122			fprintf(stderr, "%s:%d:\tsymbol %s %s value contains %s\n",
1123				prop->file->name, prop->lineno,
1124				sym->name ? sym->name : "<choice>",
1125				prop_get_type_name(prop->type),
1126				next_sym->name ? next_sym->name : "<choice>");
1127		} else if (stack->prop) {
1128			fprintf(stderr, "%s:%d:\tsymbol %s depends on %s\n",
1129				prop->file->name, prop->lineno,
1130				sym->name ? sym->name : "<choice>",
1131				next_sym->name ? next_sym->name : "<choice>");
1132		} else if (sym_is_choice(sym)) {
1133			fprintf(stderr, "%s:%d:\tchoice %s contains symbol %s\n",
1134				menu->file->name, menu->lineno,
1135				sym->name ? sym->name : "<choice>",
1136				next_sym->name ? next_sym->name : "<choice>");
1137		} else if (sym_is_choice_value(sym)) {
1138			fprintf(stderr, "%s:%d:\tsymbol %s is part of choice %s\n",
1139				menu->file->name, menu->lineno,
1140				sym->name ? sym->name : "<choice>",
1141				next_sym->name ? next_sym->name : "<choice>");
1142		} else {
1143			fprintf(stderr, "%s:%d:\tsymbol %s is selected by %s\n",
1144				prop->file->name, prop->lineno,
1145				sym->name ? sym->name : "<choice>",
1146				next_sym->name ? next_sym->name : "<choice>");
1147		}
1148	}
1149
1150	if (check_top == &cv_stack)
1151		dep_stack_remove();
1152}
1153
1154static struct symbol *sym_check_expr_deps(struct expr *e)
1155{
1156	struct symbol *sym;
1157
1158	if (!e)
1159		return NULL;
1160	switch (e->type) {
1161	case E_OR:
1162	case E_AND:
1163		sym = sym_check_expr_deps(e->left.expr);
1164		if (sym)
1165			return sym;
1166		return sym_check_expr_deps(e->right.expr);
1167	case E_NOT:
1168		return sym_check_expr_deps(e->left.expr);
1169	case E_EQUAL:
1170	case E_GEQ:
1171	case E_GTH:
1172	case E_LEQ:
1173	case E_LTH:
1174	case E_UNEQUAL:
1175		sym = sym_check_deps(e->left.sym);
1176		if (sym)
1177			return sym;
1178		return sym_check_deps(e->right.sym);
1179	case E_SYMBOL:
1180		return sym_check_deps(e->left.sym);
1181	default:
1182		break;
1183	}
1184	printf("Oops! How to check %d?\n", e->type);
1185	return NULL;
1186}
1187
1188/* return NULL when dependencies are OK */
1189static struct symbol *sym_check_sym_deps(struct symbol *sym)
1190{
1191	struct symbol *sym2;
1192	struct property *prop;
1193	struct dep_stack stack;
1194
1195	dep_stack_insert(&stack, sym);
1196
1197	sym2 = sym_check_expr_deps(sym->rev_dep.expr);
1198	if (sym2)
1199		goto out;
1200
1201	for (prop = sym->prop; prop; prop = prop->next) {
1202		if (prop->type == P_CHOICE || prop->type == P_SELECT)
1203			continue;
1204		stack.prop = prop;
1205		sym2 = sym_check_expr_deps(prop->visible.expr);
1206		if (sym2)
1207			break;
1208		if (prop->type != P_DEFAULT || sym_is_choice(sym))
1209			continue;
1210		stack.expr = prop->expr;
1211		sym2 = sym_check_expr_deps(prop->expr);
1212		if (sym2)
1213			break;
1214		stack.expr = NULL;
1215	}
1216
1217out:
1218	dep_stack_remove();
1219
1220	return sym2;
1221}
1222
1223static struct symbol *sym_check_choice_deps(struct symbol *choice)
1224{
1225	struct symbol *sym, *sym2;
1226	struct property *prop;
1227	struct expr *e;
1228	struct dep_stack stack;
1229
1230	dep_stack_insert(&stack, choice);
1231
1232	prop = sym_get_choice_prop(choice);
1233	expr_list_for_each_sym(prop->expr, e, sym)
1234		sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1235
1236	choice->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1237	sym2 = sym_check_sym_deps(choice);
1238	choice->flags &= ~SYMBOL_CHECK;
1239	if (sym2)
1240		goto out;
1241
1242	expr_list_for_each_sym(prop->expr, e, sym) {
1243		sym2 = sym_check_sym_deps(sym);
1244		if (sym2)
1245			break;
1246	}
1247out:
1248	expr_list_for_each_sym(prop->expr, e, sym)
1249		sym->flags &= ~SYMBOL_CHECK;
1250
1251	if (sym2 && sym_is_choice_value(sym2) &&
1252	    prop_get_symbol(sym_get_choice_prop(sym2)) == choice)
1253		sym2 = choice;
1254
1255	dep_stack_remove();
1256
1257	return sym2;
1258}
1259
1260struct symbol *sym_check_deps(struct symbol *sym)
1261{
1262	struct symbol *sym2;
1263	struct property *prop;
1264
1265	if (sym->flags & SYMBOL_CHECK) {
1266		sym_check_print_recursive(sym);
1267		return sym;
1268	}
1269	if (sym->flags & SYMBOL_CHECKED)
1270		return NULL;
1271
1272	if (sym_is_choice_value(sym)) {
1273		struct dep_stack stack;
1274
1275		/* for choice groups start the check with main choice symbol */
1276		dep_stack_insert(&stack, sym);
1277		prop = sym_get_choice_prop(sym);
1278		sym2 = sym_check_deps(prop_get_symbol(prop));
1279		dep_stack_remove();
1280	} else if (sym_is_choice(sym)) {
1281		sym2 = sym_check_choice_deps(sym);
1282	} else {
1283		sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
1284		sym2 = sym_check_sym_deps(sym);
1285		sym->flags &= ~SYMBOL_CHECK;
1286	}
1287
1288	if (sym2 && sym2 == sym)
1289		sym2 = NULL;
1290
1291	return sym2;
1292}
1293
1294struct property *prop_alloc(enum prop_type type, struct symbol *sym)
1295{
1296	struct property *prop;
1297	struct property **propp;
1298
1299	prop = xmalloc(sizeof(*prop));
1300	memset(prop, 0, sizeof(*prop));
1301	prop->type = type;
1302	prop->sym = sym;
1303	prop->file = current_file;
1304	prop->lineno = zconf_lineno();
1305
1306	/* append property to the prop list of symbol */
1307	if (sym) {
1308		for (propp = &sym->prop; *propp; propp = &(*propp)->next)
1309			;
1310		*propp = prop;
1311	}
1312
1313	return prop;
1314}
1315
1316struct symbol *prop_get_symbol(struct property *prop)
1317{
1318	if (prop->expr && (prop->expr->type == E_SYMBOL ||
1319			   prop->expr->type == E_LIST))
1320		return prop->expr->left.sym;
1321	return NULL;
1322}
1323
1324const char *prop_get_type_name(enum prop_type type)
1325{
1326	switch (type) {
1327	case P_PROMPT:
1328		return "prompt";
1329	case P_ENV:
1330		return "env";
1331	case P_COMMENT:
1332		return "comment";
1333	case P_MENU:
1334		return "menu";
1335	case P_DEFAULT:
1336		return "default";
1337	case P_CHOICE:
1338		return "choice";
1339	case P_SELECT:
1340		return "select";
1341	case P_RANGE:
1342		return "range";
1343	case P_SYMBOL:
1344		return "symbol";
1345	case P_UNKNOWN:
1346		break;
1347	}
1348	return "unknown";
1349}
1350
1351static void prop_add_env(const char *env)
1352{
1353	struct symbol *sym, *sym2;
1354	struct property *prop;
1355	char *p;
1356
1357	sym = current_entry->sym;
1358	sym->flags |= SYMBOL_AUTO;
1359	for_all_properties(sym, prop, P_ENV) {
1360		sym2 = prop_get_symbol(prop);
1361		if (strcmp(sym2->name, env))
1362			menu_warn(current_entry, "redefining environment symbol from %s",
1363				  sym2->name);
1364		return;
1365	}
1366
1367	prop = prop_alloc(P_ENV, sym);
1368	prop->expr = expr_alloc_symbol(sym_lookup(env, SYMBOL_CONST));
1369
1370	sym_env_list = expr_alloc_one(E_LIST, sym_env_list);
1371	sym_env_list->right.sym = sym;
1372
1373	p = getenv(env);
1374	if (p)
1375		sym_add_default(sym, p);
1376	else
1377		menu_warn(current_entry, "environment variable %s undefined", env);
1378}
1379