xref: /linux/scripts/kconfig/expr.h (revision 68e5c7d4cefb66de3953a874e670ec8f1ce86a24)
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  * @val: calculated tristate value
43  * @val_is_valid: indicate whether the value is valid
44  * @left:  left node
45  * @right: right node
46  */
47 struct expr {
48 	struct hlist_node node;
49 	enum expr_type type;
50 	tristate val;
51 	bool val_is_valid;
52 	union expr_data left, right;
53 };
54 
55 #define EXPR_OR(dep1, dep2)	(((dep1)>(dep2))?(dep1):(dep2))
56 #define EXPR_AND(dep1, dep2)	(((dep1)<(dep2))?(dep1):(dep2))
57 #define EXPR_NOT(dep)		(2-(dep))
58 
59 struct expr_value {
60 	struct expr *expr;
61 	tristate tri;
62 };
63 
64 struct symbol_value {
65 	void *val;
66 	tristate tri;
67 };
68 
69 enum symbol_type {
70 	S_UNKNOWN, S_BOOLEAN, S_TRISTATE, S_INT, S_HEX, S_STRING
71 };
72 
73 /* enum values are used as index to symbol.def[] */
74 enum {
75 	S_DEF_USER,		/* main user value */
76 	S_DEF_AUTO,		/* values read from auto.conf */
77 	S_DEF_DEF3,		/* Reserved for UI usage */
78 	S_DEF_DEF4,		/* Reserved for UI usage */
79 	S_DEF_COUNT
80 };
81 
82 /*
83  * Represents a configuration symbol.
84  *
85  * Choices are represented as a special kind of symbol with null name.
86  *
87  * @choice_link: linked to menu::choice_members
88  */
89 struct symbol {
90 	/* link node for the hash table */
91 	struct hlist_node node;
92 
93 	/* The name of the symbol, e.g. "FOO" for 'config FOO' */
94 	char *name;
95 
96 	/* S_BOOLEAN, S_TRISTATE, ... */
97 	enum symbol_type type;
98 
99 	/*
100 	 * The calculated value of the symbol. The SYMBOL_VALID bit is set in
101 	 * 'flags' when this is up to date. Note that this value might differ
102 	 * from the user value set in e.g. a .config file, due to visibility.
103 	 */
104 	struct symbol_value curr;
105 
106 	/*
107 	 * Values for the symbol provided from outside. def[S_DEF_USER] holds
108 	 * the .config value.
109 	 */
110 	struct symbol_value def[S_DEF_COUNT];
111 
112 	/*
113 	 * An upper bound on the tristate value the user can set for the symbol
114 	 * if it is a boolean or tristate. Calculated from prompt dependencies,
115 	 * which also inherit dependencies from enclosing menus, choices, and
116 	 * ifs. If 'n', the user value will be ignored.
117 	 *
118 	 * Symbols lacking prompts always have visibility 'n'.
119 	 */
120 	tristate visible;
121 
122 	/* config entries associated with this symbol */
123 	struct list_head menus;
124 
125 	struct list_head choice_link;
126 
127 	/* SYMBOL_* flags */
128 	int flags;
129 
130 	/* List of properties. See prop_type. */
131 	struct property *prop;
132 
133 	/* Dependencies from enclosing menus, choices, and ifs */
134 	struct expr_value dir_dep;
135 
136 	/* Reverse dependencies through being selected by other symbols */
137 	struct expr_value rev_dep;
138 
139 	/*
140 	 * "Weak" reverse dependencies through being implied by other symbols
141 	 */
142 	struct expr_value implied;
143 };
144 
145 #define SYMBOL_CONST      0x0001  /* symbol is const */
146 #define SYMBOL_CHECK      0x0008  /* used during dependency checking */
147 #define SYMBOL_VALID      0x0080  /* set when symbol.curr is calculated */
148 #define SYMBOL_WRITE      0x0200  /* write symbol to file (KCONFIG_CONFIG) */
149 #define SYMBOL_WRITTEN    0x0800  /* track info to avoid double-write to .config */
150 #define SYMBOL_CHECKED    0x2000  /* used during dependency checking */
151 #define SYMBOL_WARNED     0x8000  /* warning has been issued */
152 
153 /* Set when symbol.def[] is used */
154 #define SYMBOL_DEF        0x10000  /* First bit of SYMBOL_DEF */
155 #define SYMBOL_DEF_USER   0x10000  /* symbol.def[S_DEF_USER] is valid */
156 #define SYMBOL_DEF_AUTO   0x20000  /* symbol.def[S_DEF_AUTO] is valid */
157 #define SYMBOL_DEF3       0x40000  /* symbol.def[S_DEF_3] is valid */
158 #define SYMBOL_DEF4       0x80000  /* symbol.def[S_DEF_4] is valid */
159 
160 #define SYMBOL_MAXLENGTH	256
161 
162 /* A property represent the config options that can be associated
163  * with a config "symbol".
164  * Sample:
165  * config FOO
166  *         default y
167  *         prompt "foo prompt"
168  *         select BAR
169  * config BAZ
170  *         int "BAZ Value"
171  *         range 1..255
172  *
173  * Please, also check parser.y:print_symbol() when modifying the
174  * list of property types!
175  */
176 enum prop_type {
177 	P_UNKNOWN,
178 	P_PROMPT,   /* prompt "foo prompt" or "BAZ Value" */
179 	P_COMMENT,  /* text associated with a comment */
180 	P_MENU,     /* prompt associated with a menu or menuconfig symbol */
181 	P_DEFAULT,  /* default y */
182 	P_SELECT,   /* select BAR */
183 	P_IMPLY,    /* imply BAR */
184 	P_RANGE,    /* range 7..100 (for a symbol) */
185 };
186 
187 struct property {
188 	struct property *next;     /* next property - null if last */
189 	enum prop_type type;       /* type of property */
190 	const char *text;          /* the prompt value - P_PROMPT, P_MENU, P_COMMENT */
191 	struct expr_value visible;
192 	struct expr *expr;         /* the optional conditional part of the property */
193 	struct menu *menu;         /* the menu the property are associated with
194 	                            * valid for: P_SELECT, P_RANGE,
195 	                            * P_PROMPT, P_DEFAULT, P_MENU, P_COMMENT */
196 	const char *filename;      /* what file was this property defined */
197 	int lineno;                /* what lineno was this property defined */
198 };
199 
200 #define for_all_properties(sym, st, tok) \
201 	for (st = sym->prop; st; st = st->next) \
202 		if (st->type == (tok))
203 #define for_all_defaults(sym, st) for_all_properties(sym, st, P_DEFAULT)
204 #define for_all_prompts(sym, st) \
205 	for (st = sym->prop; st; st = st->next) \
206 		if (st->text)
207 
208 /*
209  * Represents a node in the menu tree, as seen in e.g. menuconfig (though used
210  * for all front ends). Each symbol, menu, etc. defined in the Kconfig files
211  * gets a node. A symbol defined in multiple locations gets one node at each
212  * location.
213  *
214  * @choice_members: list of choice members with priority.
215  */
216 struct menu {
217 	/* The next menu node at the same level */
218 	struct menu *next;
219 
220 	/* The parent menu node, corresponding to e.g. a menu or choice */
221 	struct menu *parent;
222 
223 	/* The first child menu node, for e.g. menus and choices */
224 	struct menu *list;
225 
226 	/*
227 	 * The symbol associated with the menu node. Choices are implemented as
228 	 * a special kind of symbol. NULL for menus, comments, and ifs.
229 	 */
230 	struct symbol *sym;
231 
232 	struct list_head link;	/* link to symbol::menus */
233 
234 	struct list_head choice_members;
235 
236 	/*
237 	 * The prompt associated with the node. This holds the prompt for a
238 	 * symbol as well as the text for a menu or comment, along with the
239 	 * type (P_PROMPT, P_MENU, etc.)
240 	 */
241 	struct property *prompt;
242 
243 	/*
244 	 * 'visible if' dependencies. If more than one is given, they will be
245 	 * ANDed together.
246 	 */
247 	struct expr *visibility;
248 
249 	/*
250 	 * Ordinary dependencies from e.g. 'depends on' and 'if', ANDed
251 	 * together
252 	 */
253 	struct expr *dep;
254 
255 	/* MENU_* flags */
256 	unsigned int flags;
257 
258 	/* Any help text associated with the node */
259 	char *help;
260 
261 	/* The location where the menu node appears in the Kconfig files */
262 	const char *filename;
263 	int lineno;
264 
265 	/* For use by front ends that need to store auxiliary data */
266 	void *data;
267 };
268 
269 /*
270  * Set on a menu node when the corresponding symbol changes state in some way.
271  * Can be checked by front ends.
272  */
273 #define MENU_CHANGED		0x0001
274 
275 #define MENU_ROOT		0x0002
276 
277 struct jump_key {
278 	struct list_head entries;
279 	size_t offset;
280 	struct menu *target;
281 };
282 
283 extern struct symbol symbol_yes, symbol_no, symbol_mod;
284 extern struct symbol *modules_sym;
285 extern int cdebug;
286 struct expr *expr_alloc_symbol(struct symbol *sym);
287 struct expr *expr_alloc_one(enum expr_type type, struct expr *ce);
288 struct expr *expr_alloc_two(enum expr_type type, struct expr *e1, struct expr *e2);
289 struct expr *expr_alloc_comp(enum expr_type type, struct symbol *s1, struct symbol *s2);
290 struct expr *expr_alloc_and(struct expr *e1, struct expr *e2);
291 struct expr *expr_alloc_or(struct expr *e1, struct expr *e2);
292 void expr_eliminate_eq(struct expr **ep1, struct expr **ep2);
293 bool expr_eq(struct expr *e1, struct expr *e2);
294 tristate expr_calc_value(struct expr *e);
295 struct expr *expr_eliminate_dups(struct expr *e);
296 struct expr *expr_transform(struct expr *e);
297 bool expr_contains_symbol(struct expr *dep, struct symbol *sym);
298 bool expr_depends_symbol(struct expr *dep, struct symbol *sym);
299 struct expr *expr_trans_compare(struct expr *e, enum expr_type type, struct symbol *sym);
300 
301 void expr_fprint(struct expr *e, FILE *out);
302 struct gstr; /* forward */
303 void expr_gstr_print(const struct expr *e, struct gstr *gs);
304 void expr_gstr_print_revdep(struct expr *e, struct gstr *gs,
305 			    tristate pr_type, const char *title);
306 
307 static inline bool expr_is_yes(const struct expr *e)
308 {
309 	return !e || (e->type == E_SYMBOL && e->left.sym == &symbol_yes);
310 }
311 
312 #ifdef __cplusplus
313 }
314 #endif
315 
316 #endif /* EXPR_H */
317