The "imply" keyword is a weak version of "select" where the target config symbol can still be turned off, avoiding those pitfalls that come with the "select" keyword. This is useful e.g. with multiple drivers that want to indicate their ability to hook into a secondary subsystem while allowing the user to configure that subsystem out without also having to unset these drivers. Currently, the same effect can almost be achieved with: config DRIVER_A tristate config DRIVER_B tristate config DRIVER_C tristate config DRIVER_D tristate [...] config SUBSYSTEM_X tristate default DRIVER_A || DRIVER_B || DRIVER_C || DRIVER_D || [...] This is unwieldy to maintain especially with a large number of drivers. Furthermore, there is no easy way to restrict the choice for SUBSYSTEM_X to y or n, excluding m, when some drivers are built-in. The "select" keyword allows for excluding m, but it excludes n as well. Hence this "imply" keyword. The above becomes: config DRIVER_A tristate imply SUBSYSTEM_X config DRIVER_B tristate imply SUBSYSTEM_X [...] config SUBSYSTEM_X tristate This is much cleaner, and way more flexible than "select". SUBSYSTEM_X can still be configured out, and it can be set as a module when none of the drivers are configured in or all of them are modular. Signed-off-by: Nicolas Pitre <nico@linaro.org> Acked-by: Richard Cochran <richardcochran@gmail.com> Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: John Stultz <john.stultz@linaro.org> Reviewed-by: Josh Triplett <josh@joshtriplett.org> Cc: Paul Bolle <pebolle@tiscali.nl> Cc: linux-kbuild@vger.kernel.org Cc: netdev@vger.kernel.org Cc: Michal Marek <mmarek@suse.com> Cc: Edward Cree <ecree@solarflare.com> Link: http://lkml.kernel.org/r/1478841010-28605-2-git-send-email-nicolas.pitre@linaro.org Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
		
			
				
	
	
		
			241 lines
		
	
	
		
			7.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			241 lines
		
	
	
		
			7.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
 | |
|  * Released under the terms of the GNU GPL v2.0.
 | |
|  */
 | |
| 
 | |
| #ifndef EXPR_H
 | |
| #define EXPR_H
 | |
| 
 | |
| #ifdef __cplusplus
 | |
| extern "C" {
 | |
| #endif
 | |
| 
 | |
| #include <assert.h>
 | |
| #include <stdio.h>
 | |
| #include "list.h"
 | |
| #ifndef __cplusplus
 | |
| #include <stdbool.h>
 | |
| #endif
 | |
| 
 | |
| struct file {
 | |
| 	struct file *next;
 | |
| 	struct file *parent;
 | |
| 	const char *name;
 | |
| 	int lineno;
 | |
| };
 | |
| 
 | |
| typedef enum tristate {
 | |
| 	no, mod, yes
 | |
| } tristate;
 | |
| 
 | |
| enum expr_type {
 | |
| 	E_NONE, E_OR, E_AND, E_NOT,
 | |
| 	E_EQUAL, E_UNEQUAL, E_LTH, E_LEQ, E_GTH, E_GEQ,
 | |
| 	E_LIST, E_SYMBOL, E_RANGE
 | |
| };
 | |
| 
 | |
| union expr_data {
 | |
| 	struct expr *expr;
 | |
| 	struct symbol *sym;
 | |
| };
 | |
| 
 | |
| struct expr {
 | |
| 	enum expr_type type;
 | |
| 	union expr_data left, right;
 | |
| };
 | |
| 
 | |
| #define EXPR_OR(dep1, dep2)	(((dep1)>(dep2))?(dep1):(dep2))
 | |
| #define EXPR_AND(dep1, dep2)	(((dep1)<(dep2))?(dep1):(dep2))
 | |
| #define EXPR_NOT(dep)		(2-(dep))
 | |
| 
 | |
| #define expr_list_for_each_sym(l, e, s) \
 | |
| 	for (e = (l); e && (s = e->right.sym); e = e->left.expr)
 | |
| 
 | |
| struct expr_value {
 | |
| 	struct expr *expr;
 | |
| 	tristate tri;
 | |
| };
 | |
| 
 | |
| struct symbol_value {
 | |
| 	void *val;
 | |
| 	tristate tri;
 | |
| };
 | |
| 
 | |
| enum symbol_type {
 | |
| 	S_UNKNOWN, S_BOOLEAN, S_TRISTATE, S_INT, S_HEX, S_STRING, S_OTHER
 | |
| };
 | |
| 
 | |
| /* enum values are used as index to symbol.def[] */
 | |
| enum {
 | |
| 	S_DEF_USER,		/* main user value */
 | |
| 	S_DEF_AUTO,		/* values read from auto.conf */
 | |
| 	S_DEF_DEF3,		/* Reserved for UI usage */
 | |
| 	S_DEF_DEF4,		/* Reserved for UI usage */
 | |
| 	S_DEF_COUNT
 | |
| };
 | |
| 
 | |
| struct symbol {
 | |
| 	struct symbol *next;
 | |
| 	char *name;
 | |
| 	enum symbol_type type;
 | |
| 	struct symbol_value curr;
 | |
| 	struct symbol_value def[S_DEF_COUNT];
 | |
| 	tristate visible;
 | |
| 	int flags;
 | |
| 	struct property *prop;
 | |
| 	struct expr_value dir_dep;
 | |
| 	struct expr_value rev_dep;
 | |
| 	struct expr_value implied;
 | |
| };
 | |
| 
 | |
| #define for_all_symbols(i, sym) for (i = 0; i < SYMBOL_HASHSIZE; i++) for (sym = symbol_hash[i]; sym; sym = sym->next) if (sym->type != S_OTHER)
 | |
| 
 | |
| #define SYMBOL_CONST      0x0001  /* symbol is const */
 | |
| #define SYMBOL_CHECK      0x0008  /* used during dependency checking */
 | |
| #define SYMBOL_CHOICE     0x0010  /* start of a choice block (null name) */
 | |
| #define SYMBOL_CHOICEVAL  0x0020  /* used as a value in a choice block */
 | |
| #define SYMBOL_VALID      0x0080  /* set when symbol.curr is calculated */
 | |
| #define SYMBOL_OPTIONAL   0x0100  /* choice is optional - values can be 'n' */
 | |
| #define SYMBOL_WRITE      0x0200  /* write symbol to file (KCONFIG_CONFIG) */
 | |
| #define SYMBOL_CHANGED    0x0400  /* ? */
 | |
| #define SYMBOL_AUTO       0x1000  /* value from environment variable */
 | |
| #define SYMBOL_CHECKED    0x2000  /* used during dependency checking */
 | |
| #define SYMBOL_WARNED     0x8000  /* warning has been issued */
 | |
| 
 | |
| /* Set when symbol.def[] is used */
 | |
| #define SYMBOL_DEF        0x10000  /* First bit of SYMBOL_DEF */
 | |
| #define SYMBOL_DEF_USER   0x10000  /* symbol.def[S_DEF_USER] is valid */
 | |
| #define SYMBOL_DEF_AUTO   0x20000  /* symbol.def[S_DEF_AUTO] is valid */
 | |
| #define SYMBOL_DEF3       0x40000  /* symbol.def[S_DEF_3] is valid */
 | |
| #define SYMBOL_DEF4       0x80000  /* symbol.def[S_DEF_4] is valid */
 | |
| 
 | |
| /* choice values need to be set before calculating this symbol value */
 | |
| #define SYMBOL_NEED_SET_CHOICE_VALUES  0x100000
 | |
| 
 | |
| /* Set symbol to y if allnoconfig; used for symbols that hide others */
 | |
| #define SYMBOL_ALLNOCONFIG_Y 0x200000
 | |
| 
 | |
| #define SYMBOL_MAXLENGTH	256
 | |
| #define SYMBOL_HASHSIZE		9973
 | |
| 
 | |
| /* A property represent the config options that can be associated
 | |
|  * with a config "symbol".
 | |
|  * Sample:
 | |
|  * config FOO
 | |
|  *         default y
 | |
|  *         prompt "foo prompt"
 | |
|  *         select BAR
 | |
|  * config BAZ
 | |
|  *         int "BAZ Value"
 | |
|  *         range 1..255
 | |
|  */
 | |
| enum prop_type {
 | |
| 	P_UNKNOWN,
 | |
| 	P_PROMPT,   /* prompt "foo prompt" or "BAZ Value" */
 | |
| 	P_COMMENT,  /* text associated with a comment */
 | |
| 	P_MENU,     /* prompt associated with a menuconfig option */
 | |
| 	P_DEFAULT,  /* default y */
 | |
| 	P_CHOICE,   /* choice value */
 | |
| 	P_SELECT,   /* select BAR */
 | |
| 	P_IMPLY,    /* imply BAR */
 | |
| 	P_RANGE,    /* range 7..100 (for a symbol) */
 | |
| 	P_ENV,      /* value from environment variable */
 | |
| 	P_SYMBOL,   /* where a symbol is defined */
 | |
| };
 | |
| 
 | |
| struct property {
 | |
| 	struct property *next;     /* next property - null if last */
 | |
| 	struct symbol *sym;        /* the symbol for which the property is associated */
 | |
| 	enum prop_type type;       /* type of property */
 | |
| 	const char *text;          /* the prompt value - P_PROMPT, P_MENU, P_COMMENT */
 | |
| 	struct expr_value visible;
 | |
| 	struct expr *expr;         /* the optional conditional part of the property */
 | |
| 	struct menu *menu;         /* the menu the property are associated with
 | |
| 	                            * valid for: P_SELECT, P_RANGE, P_CHOICE,
 | |
| 	                            * P_PROMPT, P_DEFAULT, P_MENU, P_COMMENT */
 | |
| 	struct file *file;         /* what file was this property defined */
 | |
| 	int lineno;                /* what lineno was this property defined */
 | |
| };
 | |
| 
 | |
| #define for_all_properties(sym, st, tok) \
 | |
| 	for (st = sym->prop; st; st = st->next) \
 | |
| 		if (st->type == (tok))
 | |
| #define for_all_defaults(sym, st) for_all_properties(sym, st, P_DEFAULT)
 | |
| #define for_all_choices(sym, st) for_all_properties(sym, st, P_CHOICE)
 | |
| #define for_all_prompts(sym, st) \
 | |
| 	for (st = sym->prop; st; st = st->next) \
 | |
| 		if (st->text)
 | |
| 
 | |
| struct menu {
 | |
| 	struct menu *next;
 | |
| 	struct menu *parent;
 | |
| 	struct menu *list;
 | |
| 	struct symbol *sym;
 | |
| 	struct property *prompt;
 | |
| 	struct expr *visibility;
 | |
| 	struct expr *dep;
 | |
| 	unsigned int flags;
 | |
| 	char *help;
 | |
| 	struct file *file;
 | |
| 	int lineno;
 | |
| 	void *data;
 | |
| };
 | |
| 
 | |
| #define MENU_CHANGED		0x0001
 | |
| #define MENU_ROOT		0x0002
 | |
| 
 | |
| struct jump_key {
 | |
| 	struct list_head entries;
 | |
| 	size_t offset;
 | |
| 	struct menu *target;
 | |
| 	int index;
 | |
| };
 | |
| 
 | |
| #define JUMP_NB			9
 | |
| 
 | |
| extern struct file *file_list;
 | |
| extern struct file *current_file;
 | |
| struct file *lookup_file(const char *name);
 | |
| 
 | |
| extern struct symbol symbol_yes, symbol_no, symbol_mod;
 | |
| extern struct symbol *modules_sym;
 | |
| extern struct symbol *sym_defconfig_list;
 | |
| extern int cdebug;
 | |
| struct expr *expr_alloc_symbol(struct symbol *sym);
 | |
| struct expr *expr_alloc_one(enum expr_type type, struct expr *ce);
 | |
| struct expr *expr_alloc_two(enum expr_type type, struct expr *e1, struct expr *e2);
 | |
| struct expr *expr_alloc_comp(enum expr_type type, struct symbol *s1, struct symbol *s2);
 | |
| struct expr *expr_alloc_and(struct expr *e1, struct expr *e2);
 | |
| struct expr *expr_alloc_or(struct expr *e1, struct expr *e2);
 | |
| struct expr *expr_copy(const struct expr *org);
 | |
| void expr_free(struct expr *e);
 | |
| void expr_eliminate_eq(struct expr **ep1, struct expr **ep2);
 | |
| tristate expr_calc_value(struct expr *e);
 | |
| struct expr *expr_trans_bool(struct expr *e);
 | |
| struct expr *expr_eliminate_dups(struct expr *e);
 | |
| struct expr *expr_transform(struct expr *e);
 | |
| int expr_contains_symbol(struct expr *dep, struct symbol *sym);
 | |
| bool expr_depends_symbol(struct expr *dep, struct symbol *sym);
 | |
| struct expr *expr_trans_compare(struct expr *e, enum expr_type type, struct symbol *sym);
 | |
| struct expr *expr_simplify_unmet_dep(struct expr *e1, struct expr *e2);
 | |
| 
 | |
| void expr_fprint(struct expr *e, FILE *out);
 | |
| struct gstr; /* forward */
 | |
| void expr_gstr_print(struct expr *e, struct gstr *gs);
 | |
| 
 | |
| static inline int expr_is_yes(struct expr *e)
 | |
| {
 | |
| 	return !e || (e->type == E_SYMBOL && e->left.sym == &symbol_yes);
 | |
| }
 | |
| 
 | |
| static inline int expr_is_no(struct expr *e)
 | |
| {
 | |
| 	return e && (e->type == E_SYMBOL && e->left.sym == &symbol_no);
 | |
| }
 | |
| 
 | |
| #ifdef __cplusplus
 | |
| }
 | |
| #endif
 | |
| 
 | |
| #endif /* EXPR_H */
 |