/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
 */

#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
};

/* 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
};

/*
 * Represents a configuration symbol.
 *
 * Choices are represented as a special kind of symbol and have the
 * SYMBOL_CHOICE bit set in 'flags'.
 */
struct symbol {
        /* The next symbol in the same bucket in the symbol hash table */
        struct symbol *next;

        /* 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;

        /* 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;

        /*
         * "Weak" reverse dependencies through being implied by other symbols
         */
        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)

#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_WRITTEN    0x0800  /* track info to avoid double-write to .config */
#define SYMBOL_NO_WRITE   0x1000  /* Symbol for internal use only; it will not be written */
#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

#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
 *
 * 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 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_SYMBOL,   /* where a symbol is defined */
};

struct property {
        struct property *next;     /* next property - null if last */
        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)

/*
 * 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.
 */
struct menu {
        /* 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;

        /*
         * 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;

        /* The location where the menu node appears in the Kconfig files */
        struct file *file;
        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;
};

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 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);
int expr_eq(struct expr *e1, struct expr *e2);
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);

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_revdep(struct expr *e, struct gstr *gs,
                            tristate pr_type, const char *title);

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 */