xref: /linux/scripts/kconfig/expr.h (revision f93d6bfbd2f74d79041c153a59df5336f6e9a14a)
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 #ifndef __cplusplus
16 #include <stdbool.h>
17 #endif
18 
19 #include <list_types.h>
20 
21 typedef enum tristate {
22 	no, mod, yes
23 } tristate;
24 
25 enum expr_type {
26 	E_NONE, E_OR, E_AND, E_NOT,
27 	E_EQUAL, E_UNEQUAL, E_LTH, E_LEQ, E_GTH, E_GEQ,
28 	E_SYMBOL, E_RANGE
29 };
30 
31 union expr_data {
32 	struct expr * const expr;
33 	struct symbol * const sym;
34 	void *_initdata;
35 };
36 
37 /**
38  * struct expr - expression
39  *
40  * @node:  link node for the hash table
41  * @type:  expressoin type
42  * @left:  left node
43  * @right: right node
44  */
45 struct expr {
46 	struct hlist_node node;
47 	enum expr_type type;
48 	union expr_data left, right;
49 };
50 
51 #define EXPR_OR(dep1, dep2)	(((dep1)>(dep2))?(dep1):(dep2))
52 #define EXPR_AND(dep1, dep2)	(((dep1)<(dep2))?(dep1):(dep2))
53 #define EXPR_NOT(dep)		(2-(dep))
54 
55 struct expr_value {
56 	struct expr *expr;
57 	tristate tri;
58 };
59 
60 struct symbol_value {
61 	void *val;
62 	tristate tri;
63 };
64 
65 enum symbol_type {
66 	S_UNKNOWN, S_BOOLEAN, S_TRISTATE, S_INT, S_HEX, S_STRING
67 };
68 
69 /* enum values are used as index to symbol.def[] */
70 enum {
71 	S_DEF_USER,		/* main user value */
72 	S_DEF_AUTO,		/* values read from auto.conf */
73 	S_DEF_DEF3,		/* Reserved for UI usage */
74 	S_DEF_DEF4,		/* Reserved for UI usage */
75 	S_DEF_COUNT
76 };
77 
78 /*
79  * Represents a configuration symbol.
80  *
81  * Choices are represented as a special kind of symbol with null name.
82  *
83  * @choice_link: linked to menu::choice_members
84  */
85 struct symbol {
86 	/* link node for the hash table */
87 	struct hlist_node node;
88 
89 	/* The name of the symbol, e.g. "FOO" for 'config FOO' */
90 	char *name;
91 
92 	/* S_BOOLEAN, S_TRISTATE, ... */
93 	enum symbol_type type;
94 
95 	/*
96 	 * The calculated value of the symbol. The SYMBOL_VALID bit is set in
97 	 * 'flags' when this is up to date. Note that this value might differ
98 	 * from the user value set in e.g. a .config file, due to visibility.
99 	 */
100 	struct symbol_value curr;
101 
102 	/*
103 	 * Values for the symbol provided from outside. def[S_DEF_USER] holds
104 	 * the .config value.
105 	 */
106 	struct symbol_value def[S_DEF_COUNT];
107 
108 	/*
109 	 * An upper bound on the tristate value the user can set for the symbol
110 	 * if it is a boolean or tristate. Calculated from prompt dependencies,
111 	 * which also inherit dependencies from enclosing menus, choices, and
112 	 * ifs. If 'n', the user value will be ignored.
113 	 *
114 	 * Symbols lacking prompts always have visibility 'n'.
115 	 */
116 	tristate visible;
117 
118 	/* config entries associated with this symbol */
119 	struct list_head menus;
120 
121 	struct list_head choice_link;
122 
123 	/* SYMBOL_* flags */
124 	int flags;
125 
126 	/* List of properties. See prop_type. */
127 	struct property *prop;
128 
129 	/* Dependencies from enclosing menus, choices, and ifs */
130 	struct expr_value dir_dep;
131 
132 	/* Reverse dependencies through being selected by other symbols */
133 	struct expr_value rev_dep;
134 
135 	/*
136 	 * "Weak" reverse dependencies through being implied by other symbols
137 	 */
138 	struct expr_value implied;
139 };
140 
141 #define SYMBOL_CONST      0x0001  /* symbol is const */
142 #define SYMBOL_CHECK      0x0008  /* used during dependency checking */
143 #define SYMBOL_VALID      0x0080  /* set when symbol.curr is calculated */
144 #define SYMBOL_WRITE      0x0200  /* write symbol to file (KCONFIG_CONFIG) */
145 #define SYMBOL_WRITTEN    0x0800  /* track info to avoid double-write to .config */
146 #define SYMBOL_CHECKED    0x2000  /* used during dependency checking */
147 #define SYMBOL_WARNED     0x8000  /* warning has been issued */
148 
149 /* Set when symbol.def[] is used */
150 #define SYMBOL_DEF        0x10000  /* First bit of SYMBOL_DEF */
151 #define SYMBOL_DEF_USER   0x10000  /* symbol.def[S_DEF_USER] is valid */
152 #define SYMBOL_DEF_AUTO   0x20000  /* symbol.def[S_DEF_AUTO] is valid */
153 #define SYMBOL_DEF3       0x40000  /* symbol.def[S_DEF_3] is valid */
154 #define SYMBOL_DEF4       0x80000  /* symbol.def[S_DEF_4] is valid */
155 
156 #define SYMBOL_MAXLENGTH	256
157 
158 /* A property represent the config options that can be associated
159  * with a config "symbol".
160  * Sample:
161  * config FOO
162  *         default y
163  *         prompt "foo prompt"
164  *         select BAR
165  * config BAZ
166  *         int "BAZ Value"
167  *         range 1..255
168  *
169  * Please, also check parser.y:print_symbol() when modifying the
170  * list of property types!
171  */
172 enum prop_type {
173 	P_UNKNOWN,
174 	P_PROMPT,   /* prompt "foo prompt" or "BAZ Value" */
175 	P_COMMENT,  /* text associated with a comment */
176 	P_MENU,     /* prompt associated with a menu or menuconfig symbol */
177 	P_DEFAULT,  /* default y */
178 	P_SELECT,   /* select BAR */
179 	P_IMPLY,    /* imply BAR */
180 	P_RANGE,    /* range 7..100 (for a symbol) */
181 };
182 
183 struct property {
184 	struct property *next;     /* next property - null if last */
185 	enum prop_type type;       /* type of property */
186 	const char *text;          /* the prompt value - P_PROMPT, P_MENU, P_COMMENT */
187 	struct expr_value visible;
188 	struct expr *expr;         /* the optional conditional part of the property */
189 	struct menu *menu;         /* the menu the property are associated with
190 	                            * valid for: P_SELECT, P_RANGE,
191 	                            * P_PROMPT, P_DEFAULT, P_MENU, P_COMMENT */
192 	const char *filename;      /* what file was this property defined */
193 	int lineno;                /* what lineno was this property defined */
194 };
195 
196 #define for_all_properties(sym, st, tok) \
197 	for (st = sym->prop; st; st = st->next) \
198 		if (st->type == (tok))
199 #define for_all_defaults(sym, st) for_all_properties(sym, st, P_DEFAULT)
200 #define for_all_prompts(sym, st) \
201 	for (st = sym->prop; st; st = st->next) \
202 		if (st->text)
203 
204 /*
205  * Represents a node in the menu tree, as seen in e.g. menuconfig (though used
206  * for all front ends). Each symbol, menu, etc. defined in the Kconfig files
207  * gets a node. A symbol defined in multiple locations gets one node at each
208  * location.
209  *
210  * @choice_members: list of choice members with priority.
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 	struct list_head choice_members;
231 
232 	/*
233 	 * The prompt associated with the node. This holds the prompt for a
234 	 * symbol as well as the text for a menu or comment, along with the
235 	 * type (P_PROMPT, P_MENU, etc.)
236 	 */
237 	struct property *prompt;
238 
239 	/*
240 	 * 'visible if' dependencies. If more than one is given, they will be
241 	 * ANDed together.
242 	 */
243 	struct expr *visibility;
244 
245 	/*
246 	 * Ordinary dependencies from e.g. 'depends on' and 'if', ANDed
247 	 * together
248 	 */
249 	struct expr *dep;
250 
251 	/* MENU_* flags */
252 	unsigned int flags;
253 
254 	/* Any help text associated with the node */
255 	char *help;
256 
257 	/* The location where the menu node appears in the Kconfig files */
258 	const char *filename;
259 	int lineno;
260 
261 	/* For use by front ends that need to store auxiliary data */
262 	void *data;
263 };
264 
265 /*
266  * Set on a menu node when the corresponding symbol changes state in some way.
267  * Can be checked by front ends.
268  */
269 #define MENU_CHANGED		0x0001
270 
271 #define MENU_ROOT		0x0002
272 
273 struct jump_key {
274 	struct list_head entries;
275 	size_t offset;
276 	struct menu *target;
277 };
278 
279 extern struct symbol symbol_yes, symbol_no, symbol_mod;
280 extern struct symbol *modules_sym;
281 extern int cdebug;
282 struct expr *expr_alloc_symbol(struct symbol *sym);
283 struct expr *expr_alloc_one(enum expr_type type, struct expr *ce);
284 struct expr *expr_alloc_two(enum expr_type type, struct expr *e1, struct expr *e2);
285 struct expr *expr_alloc_comp(enum expr_type type, struct symbol *s1, struct symbol *s2);
286 struct expr *expr_alloc_and(struct expr *e1, struct expr *e2);
287 struct expr *expr_alloc_or(struct expr *e1, struct expr *e2);
288 void expr_eliminate_eq(struct expr **ep1, struct expr **ep2);
289 bool expr_eq(struct expr *e1, struct expr *e2);
290 tristate expr_calc_value(struct expr *e);
291 struct expr *expr_eliminate_dups(struct expr *e);
292 struct expr *expr_transform(struct expr *e);
293 bool expr_contains_symbol(struct expr *dep, struct symbol *sym);
294 bool expr_depends_symbol(struct expr *dep, struct symbol *sym);
295 struct expr *expr_trans_compare(struct expr *e, enum expr_type type, struct symbol *sym);
296 
297 void expr_fprint(struct expr *e, FILE *out);
298 struct gstr; /* forward */
299 void expr_gstr_print(const struct expr *e, struct gstr *gs);
300 void expr_gstr_print_revdep(struct expr *e, struct gstr *gs,
301 			    tristate pr_type, const char *title);
302 
303 static inline bool expr_is_yes(const struct expr *e)
304 {
305 	return !e || (e->type == E_SYMBOL && e->left.sym == &symbol_yes);
306 }
307 
308 #ifdef __cplusplus
309 }
310 #endif
311 
312 #endif /* EXPR_H */
313