xref: /linux/scripts/kconfig/expr.h (revision e6a901a00822659181c93c86d8bbc2a17779fddc)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
4  */
5 
6 #ifndef EXPR_H
7 #define EXPR_H
8 
9 #ifdef __cplusplus
10 extern "C" {
11 #endif
12 
13 #include <assert.h>
14 #include <stdio.h>
15 #include "list_types.h"
16 #ifndef __cplusplus
17 #include <stdbool.h>
18 #endif
19 
20 #include "list_types.h"
21 
22 typedef enum tristate {
23 	no, mod, yes
24 } tristate;
25 
26 enum expr_type {
27 	E_NONE, E_OR, E_AND, E_NOT,
28 	E_EQUAL, E_UNEQUAL, E_LTH, E_LEQ, E_GTH, E_GEQ,
29 	E_LIST, E_SYMBOL, E_RANGE
30 };
31 
32 union expr_data {
33 	struct expr *expr;
34 	struct symbol *sym;
35 };
36 
37 struct expr {
38 	enum expr_type type;
39 	union expr_data left, right;
40 };
41 
42 #define EXPR_OR(dep1, dep2)	(((dep1)>(dep2))?(dep1):(dep2))
43 #define EXPR_AND(dep1, dep2)	(((dep1)<(dep2))?(dep1):(dep2))
44 #define EXPR_NOT(dep)		(2-(dep))
45 
46 #define expr_list_for_each_sym(l, e, s) \
47 	for (e = (l); e && (s = e->right.sym); e = e->left.expr)
48 
49 struct expr_value {
50 	struct expr *expr;
51 	tristate tri;
52 };
53 
54 struct symbol_value {
55 	void *val;
56 	tristate tri;
57 };
58 
59 enum symbol_type {
60 	S_UNKNOWN, S_BOOLEAN, S_TRISTATE, S_INT, S_HEX, S_STRING
61 };
62 
63 /* enum values are used as index to symbol.def[] */
64 enum {
65 	S_DEF_USER,		/* main user value */
66 	S_DEF_AUTO,		/* values read from auto.conf */
67 	S_DEF_DEF3,		/* Reserved for UI usage */
68 	S_DEF_DEF4,		/* Reserved for UI usage */
69 	S_DEF_COUNT
70 };
71 
72 /*
73  * Represents a configuration symbol.
74  *
75  * Choices are represented as a special kind of symbol and have the
76  * SYMBOL_CHOICE bit set in 'flags'.
77  */
78 struct symbol {
79 	/* link node for the hash table */
80 	struct hlist_node node;
81 
82 	/* The name of the symbol, e.g. "FOO" for 'config FOO' */
83 	char *name;
84 
85 	/* S_BOOLEAN, S_TRISTATE, ... */
86 	enum symbol_type type;
87 
88 	/*
89 	 * The calculated value of the symbol. The SYMBOL_VALID bit is set in
90 	 * 'flags' when this is up to date. Note that this value might differ
91 	 * from the user value set in e.g. a .config file, due to visibility.
92 	 */
93 	struct symbol_value curr;
94 
95 	/*
96 	 * Values for the symbol provided from outside. def[S_DEF_USER] holds
97 	 * the .config value.
98 	 */
99 	struct symbol_value def[S_DEF_COUNT];
100 
101 	/*
102 	 * An upper bound on the tristate value the user can set for the symbol
103 	 * if it is a boolean or tristate. Calculated from prompt dependencies,
104 	 * which also inherit dependencies from enclosing menus, choices, and
105 	 * ifs. If 'n', the user value will be ignored.
106 	 *
107 	 * Symbols lacking prompts always have visibility 'n'.
108 	 */
109 	tristate visible;
110 
111 	/* config entries associated with this symbol */
112 	struct list_head menus;
113 
114 	/* SYMBOL_* flags */
115 	int flags;
116 
117 	/* List of properties. See prop_type. */
118 	struct property *prop;
119 
120 	/* Dependencies from enclosing menus, choices, and ifs */
121 	struct expr_value dir_dep;
122 
123 	/* Reverse dependencies through being selected by other symbols */
124 	struct expr_value rev_dep;
125 
126 	/*
127 	 * "Weak" reverse dependencies through being implied by other symbols
128 	 */
129 	struct expr_value implied;
130 };
131 
132 #define SYMBOL_CONST      0x0001  /* symbol is const */
133 #define SYMBOL_CHECK      0x0008  /* used during dependency checking */
134 #define SYMBOL_CHOICE     0x0010  /* start of a choice block (null name) */
135 #define SYMBOL_CHOICEVAL  0x0020  /* used as a value in a choice block */
136 #define SYMBOL_VALID      0x0080  /* set when symbol.curr is calculated */
137 #define SYMBOL_OPTIONAL   0x0100  /* choice is optional - values can be 'n' */
138 #define SYMBOL_WRITE      0x0200  /* write symbol to file (KCONFIG_CONFIG) */
139 #define SYMBOL_CHANGED    0x0400  /* ? */
140 #define SYMBOL_WRITTEN    0x0800  /* track info to avoid double-write to .config */
141 #define SYMBOL_NO_WRITE   0x1000  /* Symbol for internal use only; it will not be written */
142 #define SYMBOL_CHECKED    0x2000  /* used during dependency checking */
143 #define SYMBOL_WARNED     0x8000  /* warning has been issued */
144 
145 /* Set when symbol.def[] is used */
146 #define SYMBOL_DEF        0x10000  /* First bit of SYMBOL_DEF */
147 #define SYMBOL_DEF_USER   0x10000  /* symbol.def[S_DEF_USER] is valid */
148 #define SYMBOL_DEF_AUTO   0x20000  /* symbol.def[S_DEF_AUTO] is valid */
149 #define SYMBOL_DEF3       0x40000  /* symbol.def[S_DEF_3] is valid */
150 #define SYMBOL_DEF4       0x80000  /* symbol.def[S_DEF_4] is valid */
151 
152 /* choice values need to be set before calculating this symbol value */
153 #define SYMBOL_NEED_SET_CHOICE_VALUES  0x100000
154 
155 #define SYMBOL_MAXLENGTH	256
156 
157 /* A property represent the config options that can be associated
158  * with a config "symbol".
159  * Sample:
160  * config FOO
161  *         default y
162  *         prompt "foo prompt"
163  *         select BAR
164  * config BAZ
165  *         int "BAZ Value"
166  *         range 1..255
167  *
168  * Please, also check parser.y:print_symbol() when modifying the
169  * list of property types!
170  */
171 enum prop_type {
172 	P_UNKNOWN,
173 	P_PROMPT,   /* prompt "foo prompt" or "BAZ Value" */
174 	P_COMMENT,  /* text associated with a comment */
175 	P_MENU,     /* prompt associated with a menu or menuconfig symbol */
176 	P_DEFAULT,  /* default y */
177 	P_CHOICE,   /* choice value */
178 	P_SELECT,   /* select BAR */
179 	P_IMPLY,    /* imply BAR */
180 	P_RANGE,    /* range 7..100 (for a symbol) */
181 	P_SYMBOL,   /* where a symbol is defined */
182 };
183 
184 struct property {
185 	struct property *next;     /* next property - null if last */
186 	enum prop_type type;       /* type of property */
187 	const char *text;          /* the prompt value - P_PROMPT, P_MENU, P_COMMENT */
188 	struct expr_value visible;
189 	struct expr *expr;         /* the optional conditional part of the property */
190 	struct menu *menu;         /* the menu the property are associated with
191 	                            * valid for: P_SELECT, P_RANGE, P_CHOICE,
192 	                            * P_PROMPT, P_DEFAULT, P_MENU, P_COMMENT */
193 	const char *filename;      /* what file was this property defined */
194 	int lineno;                /* what lineno was this property defined */
195 };
196 
197 #define for_all_properties(sym, st, tok) \
198 	for (st = sym->prop; st; st = st->next) \
199 		if (st->type == (tok))
200 #define for_all_defaults(sym, st) for_all_properties(sym, st, P_DEFAULT)
201 #define for_all_choices(sym, st) for_all_properties(sym, st, P_CHOICE)
202 #define for_all_prompts(sym, st) \
203 	for (st = sym->prop; st; st = st->next) \
204 		if (st->text)
205 
206 /*
207  * Represents a node in the menu tree, as seen in e.g. menuconfig (though used
208  * for all front ends). Each symbol, menu, etc. defined in the Kconfig files
209  * gets a node. A symbol defined in multiple locations gets one node at each
210  * location.
211  */
212 struct menu {
213 	/* The next menu node at the same level */
214 	struct menu *next;
215 
216 	/* The parent menu node, corresponding to e.g. a menu or choice */
217 	struct menu *parent;
218 
219 	/* The first child menu node, for e.g. menus and choices */
220 	struct menu *list;
221 
222 	/*
223 	 * The symbol associated with the menu node. Choices are implemented as
224 	 * a special kind of symbol. NULL for menus, comments, and ifs.
225 	 */
226 	struct symbol *sym;
227 
228 	struct list_head link;	/* link to symbol::menus */
229 
230 	/*
231 	 * The prompt associated with the node. This holds the prompt for a
232 	 * symbol as well as the text for a menu or comment, along with the
233 	 * type (P_PROMPT, P_MENU, etc.)
234 	 */
235 	struct property *prompt;
236 
237 	/*
238 	 * 'visible if' dependencies. If more than one is given, they will be
239 	 * ANDed together.
240 	 */
241 	struct expr *visibility;
242 
243 	/*
244 	 * Ordinary dependencies from e.g. 'depends on' and 'if', ANDed
245 	 * together
246 	 */
247 	struct expr *dep;
248 
249 	/* MENU_* flags */
250 	unsigned int flags;
251 
252 	/* Any help text associated with the node */
253 	char *help;
254 
255 	/* The location where the menu node appears in the Kconfig files */
256 	const char *filename;
257 	int lineno;
258 
259 	/* For use by front ends that need to store auxiliary data */
260 	void *data;
261 };
262 
263 /*
264  * Set on a menu node when the corresponding symbol changes state in some way.
265  * Can be checked by front ends.
266  */
267 #define MENU_CHANGED		0x0001
268 
269 #define MENU_ROOT		0x0002
270 
271 struct jump_key {
272 	struct list_head entries;
273 	size_t offset;
274 	struct menu *target;
275 };
276 
277 extern struct symbol symbol_yes, symbol_no, symbol_mod;
278 extern struct symbol *modules_sym;
279 extern int cdebug;
280 struct expr *expr_alloc_symbol(struct symbol *sym);
281 struct expr *expr_alloc_one(enum expr_type type, struct expr *ce);
282 struct expr *expr_alloc_two(enum expr_type type, struct expr *e1, struct expr *e2);
283 struct expr *expr_alloc_comp(enum expr_type type, struct symbol *s1, struct symbol *s2);
284 struct expr *expr_alloc_and(struct expr *e1, struct expr *e2);
285 struct expr *expr_alloc_or(struct expr *e1, struct expr *e2);
286 struct expr *expr_copy(const struct expr *org);
287 void expr_free(struct expr *e);
288 void expr_eliminate_eq(struct expr **ep1, struct expr **ep2);
289 int expr_eq(struct expr *e1, struct expr *e2);
290 tristate expr_calc_value(struct expr *e);
291 struct expr *expr_trans_bool(struct expr *e);
292 struct expr *expr_eliminate_dups(struct expr *e);
293 struct expr *expr_transform(struct expr *e);
294 int expr_contains_symbol(struct expr *dep, struct symbol *sym);
295 bool expr_depends_symbol(struct expr *dep, struct symbol *sym);
296 struct expr *expr_trans_compare(struct expr *e, enum expr_type type, struct symbol *sym);
297 
298 void expr_fprint(struct expr *e, FILE *out);
299 struct gstr; /* forward */
300 void expr_gstr_print(struct expr *e, struct gstr *gs);
301 void expr_gstr_print_revdep(struct expr *e, struct gstr *gs,
302 			    tristate pr_type, const char *title);
303 
304 static inline int expr_is_yes(struct expr *e)
305 {
306 	return !e || (e->type == E_SYMBOL && e->left.sym == &symbol_yes);
307 }
308 
309 static inline int expr_is_no(struct expr *e)
310 {
311 	return e && (e->type == E_SYMBOL && e->left.sym == &symbol_no);
312 }
313 
314 #ifdef __cplusplus
315 }
316 #endif
317 
318 #endif /* EXPR_H */
319