1 files changed, 152 insertions, 62 deletions

diff --git a/scripts/kconfig/expr.h b/scripts/kconfig/expr.h
index df198a5f4822..5f900d18dae0 100644
--- a/scripts/kconfig/expr.h
+++ b/scripts/kconfig/expr.h
@@ -1,6 +1,6 @@
+/* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
- * Released under the terms of the GNU GPL v2.0.
  */
 
 #ifndef EXPR_H
@@ -12,33 +12,43 @@ extern "C" {
 
 #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;
-};
+#include <list_types.h>
 
 typedef enum tristate {
 	no, mod, yes
 } tristate;
 
 enum expr_type {
-	E_NONE, E_OR, E_AND, E_NOT, E_EQUAL, E_UNEQUAL, E_LIST, E_SYMBOL, E_RANGE
+	E_NONE, E_OR, E_AND, E_NOT,
+	E_EQUAL, E_UNEQUAL, E_LTH, E_LEQ, E_GTH, E_GEQ,
+	E_SYMBOL, E_RANGE
 };
 
 union expr_data {
-	struct expr *expr;
-	struct symbol *sym;
+	struct expr * const expr;
+	struct symbol * const sym;
+	void *_initdata;
 };
 
+/**
+ * struct expr - expression
+ *
+ * @node:  link node for the hash table
+ * @type:  expressoin type
+ * @val: calculated tristate value
+ * @val_is_valid: indicate whether the value is valid
+ * @left:  left node
+ * @right: right node
+ */
 struct expr {
+	struct hlist_node node;
 	enum expr_type type;
+	tristate val;
+	bool val_is_valid;
 	union expr_data left, right;
 };
 
@@ -46,9 +56,6 @@ struct expr {
 #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;
@@ -60,7 +67,7 @@ struct symbol_value {
 };
 
 enum symbol_type {
-	S_UNKNOWN, S_BOOLEAN, S_TRISTATE, S_INT, S_HEX, S_STRING, S_OTHER
+	S_UNKNOWN, S_BOOLEAN, S_TRISTATE, S_INT, S_HEX, S_STRING
 };
 
 /* enum values are used as index to symbol.def[] */
@@ -72,30 +79,75 @@ enum {
 	S_DEF_COUNT
 };
 
+/*
+ * Represents a configuration symbol.
+ *
+ * Choices are represented as a special kind of symbol with null name.
+ *
+ * @choice_link: linked to menu::choice_members
+ */
 struct symbol {
-	struct symbol *next;
+	/* link node for the hash table */
+	struct hlist_node node;
+
+	/* The name of the symbol, e.g. "FOO" for 'config FOO' */
 	char *name;
+
+	/* S_BOOLEAN, S_TRISTATE, ... */
 	enum symbol_type type;
+
+	/*
+	 * The calculated value of the symbol. The SYMBOL_VALID bit is set in
+	 * 'flags' when this is up to date. Note that this value might differ
+	 * from the user value set in e.g. a .config file, due to visibility.
+	 */
 	struct symbol_value curr;
+
+	/*
+	 * Values for the symbol provided from outside. def[S_DEF_USER] holds
+	 * the .config value.
+	 */
 	struct symbol_value def[S_DEF_COUNT];
+
+	/*
+	 * An upper bound on the tristate value the user can set for the symbol
+	 * if it is a boolean or tristate. Calculated from prompt dependencies,
+	 * which also inherit dependencies from enclosing menus, choices, and
+	 * ifs. If 'n', the user value will be ignored.
+	 *
+	 * Symbols lacking prompts always have visibility 'n'.
+	 */
 	tristate visible;
+
+	/* config entries associated with this symbol */
+	struct list_head menus;
+
+	struct list_head choice_link;
+
+	/* SYMBOL_* flags */
 	int flags;
+
+	/* List of properties. See prop_type. */
 	struct property *prop;
+
+	/* Dependencies from enclosing menus, choices, and ifs */
 	struct expr_value dir_dep;
+
+	/* Reverse dependencies through being selected by other symbols */
 	struct expr_value rev_dep;
-};
 
-#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)
+	/*
+	 * "Weak" reverse dependencies through being implied by other symbols
+	 */
+	struct expr_value implied;
+};
 
 #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  /* ? */
-#define SYMBOL_CHANGED    0x0400  /* ? */
-#define SYMBOL_AUTO       0x1000  /* value from environment variable */
+#define SYMBOL_TRANS      0x0100  /* symbol is transitional only (not visible)*/
+#define SYMBOL_WRITE      0x0200  /* write symbol to file (KCONFIG_CONFIG) */
+#define SYMBOL_WRITTEN    0x0800  /* track info to avoid double-write to .config */
 #define SYMBOL_CHECKED    0x2000  /* used during dependency checking */
 #define SYMBOL_WARNED     0x8000  /* warning has been issued */
 
@@ -106,11 +158,7 @@ struct symbol {
 #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
-
 #define SYMBOL_MAXLENGTH	256
-#define SYMBOL_HASHSIZE		9973
 
 /* A property represent the config options that can be associated
  * with a config "symbol".
@@ -122,31 +170,31 @@ struct symbol {
  * config BAZ
  *         int "BAZ Value"
  *         range 1..255
+ *
+ * Please, also check parser.y:print_symbol() when modifying the
+ * list of property types!
  */
 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_MENU,     /* prompt associated with a menu or menuconfig symbol */
 	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,
+	                            * valid for: P_SELECT, P_RANGE,
 	                            * P_PROMPT, P_DEFAULT, P_MENU, P_COMMENT */
-	struct file *file;         /* what file was this property defined */
+	const char *filename;      /* what file was this property defined */
 	int lineno;                /* what lineno was this property defined */
 };
 
@@ -154,45 +202,98 @@ struct property {
 	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)
 
+enum menu_type {
+	M_CHOICE,  // "choice"
+	M_COMMENT, // "comment"
+	M_IF,      // "if"
+	M_MENU,    // "mainmenu", "menu", "menuconfig"
+	M_NORMAL,  // others, i.e., "config"
+};
+
+/*
+ * Represents a node in the menu tree, as seen in e.g. menuconfig (though used
+ * for all front ends). Each symbol, menu, etc. defined in the Kconfig files
+ * gets a node. A symbol defined in multiple locations gets one node at each
+ * location.
+ *
+ * @type: type of the menu entry
+ * @choice_members: list of choice members with priority.
+ */
 struct menu {
+	enum menu_type type;
+
+	/* The next menu node at the same level */
 	struct menu *next;
+
+	/* The parent menu node, corresponding to e.g. a menu or choice */
 	struct menu *parent;
+
+	/* The first child menu node, for e.g. menus and choices */
 	struct menu *list;
+
+	/*
+	 * The symbol associated with the menu node. Choices are implemented as
+	 * a special kind of symbol. NULL for menus, comments, and ifs.
+	 */
 	struct symbol *sym;
+
+	struct list_head link;	/* link to symbol::menus */
+
+	struct list_head choice_members;
+
+	/*
+	 * The prompt associated with the node. This holds the prompt for a
+	 * symbol as well as the text for a menu or comment, along with the
+	 * type (P_PROMPT, P_MENU, etc.)
+	 */
 	struct property *prompt;
+
+	/*
+	 * 'visible if' dependencies. If more than one is given, they will be
+	 * ANDed together.
+	 */
 	struct expr *visibility;
+
+	/*
+	 * Ordinary dependencies from e.g. 'depends on' and 'if', ANDed
+	 * together
+	 */
 	struct expr *dep;
+
+	/* MENU_* flags */
 	unsigned int flags;
+
+	/* Any help text associated with the node */
 	char *help;
-	struct file *file;
+
+	/* The location where the menu node appears in the Kconfig files */
+	const char *filename;
 	int lineno;
+
+	/* For use by front ends that need to store auxiliary data */
 	void *data;
 };
 
+/*
+ * Set on a menu node when the corresponding symbol changes state in some way.
+ * Can be checked by front ends.
+ */
 #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);
@@ -200,37 +301,26 @@ struct expr *expr_alloc_two(enum expr_type type, struct expr *e1, struct expr *e
 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);
-int expr_eq(struct expr *e1, struct expr *e2);
 void expr_eliminate_eq(struct expr **ep1, struct expr **ep2);
+bool expr_eq(struct expr *e1, struct expr *e2);
 tristate expr_calc_value(struct expr *e);
-struct expr *expr_eliminate_yn(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_contains_symbol(struct expr *dep, struct symbol *sym);
 bool expr_depends_symbol(struct expr *dep, struct symbol *sym);
-struct expr *expr_extract_eq_and(struct expr **ep1, struct expr **ep2);
-struct expr *expr_extract_eq_or(struct expr **ep1, struct expr **ep2);
-void expr_extract_eq(enum expr_type type, struct expr **ep, struct expr **ep1, struct expr **ep2);
 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);
+void expr_gstr_print(const struct expr *e, struct gstr *gs);
+void expr_gstr_print_revdep(struct expr *e, struct gstr *gs,
+			    tristate pr_type, const char *title);
 
-static inline int expr_is_yes(struct expr *e)
+static inline bool expr_is_yes(const 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