source: MondoRescue/branches/2.2.5/mindi-busybox/scripts/kconfig/symbol.c

/*
 * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
 * Released under the terms of the GNU GPL v2.0.
 */

#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include <regex.h>
#include <sys/utsname.h>

#define LKC_DIRECT_LINK
#include "lkc.h"

struct symbol symbol_yes = {
    .name = "y",
    .curr = { "y", yes },
    .flags = SYMBOL_YES|SYMBOL_VALID,
}, symbol_mod = {
    .name = "m",
    .curr = { "m", mod },
    .flags = SYMBOL_MOD|SYMBOL_VALID,
}, symbol_no = {
    .name = "n",
    .curr = { "n", no },
    .flags = SYMBOL_NO|SYMBOL_VALID,
}, symbol_empty = {
    .name = "",
    .curr = { "", no },
    .flags = SYMBOL_VALID,
};

int sym_change_count;
struct symbol *modules_sym;
tristate modules_val;

void sym_add_default(struct symbol *sym, const char *def)
{
    struct property *prop = prop_alloc(P_DEFAULT, sym);

    prop->expr = expr_alloc_symbol(sym_lookup(def, 1));
}

void sym_init(void)
{
    struct symbol *sym;
    struct utsname uts;
    char *p;
    static bool inited = false;

    if (inited)
        return;
    inited = true;

    uname(&uts);

    sym = sym_lookup("ARCH", 0);
    sym->type = S_STRING;
    sym->flags |= SYMBOL_AUTO;
    p = getenv("ARCH");
    if (p)
        sym_add_default(sym, p);

    sym = sym_lookup("KERNELVERSION", 0);
    sym->type = S_STRING;
    sym->flags |= SYMBOL_AUTO;
    p = getenv("KERNELVERSION");
    if (p)
        sym_add_default(sym, p);

    sym = sym_lookup("UNAME_RELEASE", 0);
    sym->type = S_STRING;
    sym->flags |= SYMBOL_AUTO;
    sym_add_default(sym, uts.release);
}

enum symbol_type sym_get_type(struct symbol *sym)
{
    enum symbol_type type = sym->type;

    if (type == S_TRISTATE) {
        if (sym_is_choice_value(sym) && sym->visible == yes)
            type = S_BOOLEAN;
        else if (modules_val == no)
            type = S_BOOLEAN;
    }
    return type;
}

const char *sym_type_name(enum symbol_type type)
{
    switch (type) {
    case S_BOOLEAN:
        return "boolean";
    case S_TRISTATE:
        return "tristate";
    case S_INT:
        return "integer";
    case S_HEX:
        return "hex";
    case S_STRING:
        return "string";
    case S_UNKNOWN:
        return "unknown";
    case S_OTHER:
        break;
    }
    return "???";
}

struct property *sym_get_choice_prop(struct symbol *sym)
{
    struct property *prop;

    for_all_choices(sym, prop)
        return prop;
    return NULL;
}

struct property *sym_get_default_prop(struct symbol *sym)
{
    struct property *prop;

    for_all_defaults(sym, prop) {
        prop->visible.tri = expr_calc_value(prop->visible.expr);
        if (prop->visible.tri != no)
            return prop;
    }
    return NULL;
}

struct property *sym_get_range_prop(struct symbol *sym)
{
    struct property *prop;

    for_all_properties(sym, prop, P_RANGE) {
        prop->visible.tri = expr_calc_value(prop->visible.expr);
        if (prop->visible.tri != no)
            return prop;
    }
    return NULL;
}

static int sym_get_range_val(struct symbol *sym, int base)
{
    sym_calc_value(sym);
    switch (sym->type) {
    case S_INT:
        base = 10;
        break;
    case S_HEX:
        base = 16;
        break;
    default:
        break;
    }
    return strtol(sym->curr.val, NULL, base);
}

static void sym_validate_range(struct symbol *sym)
{
    struct property *prop;
    int base, val, val2;
    char str[64];

    switch (sym->type) {
    case S_INT:
        base = 10;
        break;
    case S_HEX:
        base = 16;
        break;
    default:
        return;
    }
    prop = sym_get_range_prop(sym);
    if (!prop)
        return;
    val = strtol(sym->curr.val, NULL, base);
    val2 = sym_get_range_val(prop->expr->left.sym, base);
    if (val >= val2) {
        val2 = sym_get_range_val(prop->expr->right.sym, base);
        if (val <= val2)
            return;
    }
    if (sym->type == S_INT)
        sprintf(str, "%d", val2);
    else
        sprintf(str, "0x%x", val2);
    sym->curr.val = strdup(str);
}

static void sym_calc_visibility(struct symbol *sym)
{
    struct property *prop;
    tristate tri;

    /* any prompt visible? */
    tri = no;
    for_all_prompts(sym, prop) {
        prop->visible.tri = expr_calc_value(prop->visible.expr);
        tri = E_OR(tri, prop->visible.tri);
    }
    if (tri == mod && (sym->type != S_TRISTATE || modules_val == no))
        tri = yes;
    if (sym->visible != tri) {
        sym->visible = tri;
        sym_set_changed(sym);
    }
    if (sym_is_choice_value(sym))
        return;
    tri = no;
    if (sym->rev_dep.expr)
        tri = expr_calc_value(sym->rev_dep.expr);
    if (tri == mod && sym_get_type(sym) == S_BOOLEAN)
        tri = yes;
    if (sym->rev_dep.tri != tri) {
        sym->rev_dep.tri = tri;
        sym_set_changed(sym);
    }
}

static struct symbol *sym_calc_choice(struct symbol *sym)
{
    struct symbol *def_sym;
    struct property *prop;
    struct expr *e;

    /* is the user choice visible? */
    def_sym = sym->user.val;
    if (def_sym) {
        sym_calc_visibility(def_sym);
        if (def_sym->visible != no)
            return def_sym;
    }

    /* any of the defaults visible? */
    for_all_defaults(sym, prop) {
        prop->visible.tri = expr_calc_value(prop->visible.expr);
        if (prop->visible.tri == no)
            continue;
        def_sym = prop_get_symbol(prop);
        sym_calc_visibility(def_sym);
        if (def_sym->visible != no)
            return def_sym;
    }

    /* just get the first visible value */
    prop = sym_get_choice_prop(sym);
    for (e = prop->expr; e; e = e->left.expr) {
        def_sym = e->right.sym;
        sym_calc_visibility(def_sym);
        if (def_sym->visible != no)
            return def_sym;
    }

    /* no choice? reset tristate value */
    sym->curr.tri = no;
    return NULL;
}

void sym_calc_value(struct symbol *sym)
{
    struct symbol_value newval, oldval;
    struct property *prop;
    struct expr *e;

    if (!sym)
        return;

    if (sym->flags & SYMBOL_VALID)
        return;
    sym->flags |= SYMBOL_VALID;

    oldval = sym->curr;

    switch (sym->type) {
    case S_INT:
    case S_HEX:
    case S_STRING:
        newval = symbol_empty.curr;
        break;
    case S_BOOLEAN:
    case S_TRISTATE:
        newval = symbol_no.curr;
        break;
    default:
        sym->curr.val = sym->name;
        sym->curr.tri = no;
        return;
    }
    if (!sym_is_choice_value(sym))
        sym->flags &= ~SYMBOL_WRITE;

    sym_calc_visibility(sym);

    /* set default if recursively called */
    sym->curr = newval;

    switch (sym_get_type(sym)) {
    case S_BOOLEAN:
    case S_TRISTATE:
        if (sym_is_choice_value(sym) && sym->visible == yes) {
            prop = sym_get_choice_prop(sym);
            newval.tri = (prop_get_symbol(prop)->curr.val == sym) ? yes : no;
        } else if (E_OR(sym->visible, sym->rev_dep.tri) != no) {
            sym->flags |= SYMBOL_WRITE;
            if (sym_has_value(sym))
                newval.tri = sym->user.tri;
            else if (!sym_is_choice(sym)) {
                prop = sym_get_default_prop(sym);
                if (prop)
                    newval.tri = expr_calc_value(prop->expr);
            }
            newval.tri = E_OR(E_AND(newval.tri, sym->visible), sym->rev_dep.tri);
        } else if (!sym_is_choice(sym)) {
            prop = sym_get_default_prop(sym);
            if (prop) {
                sym->flags |= SYMBOL_WRITE;
                newval.tri = expr_calc_value(prop->expr);
            }
        }
        if (newval.tri == mod && sym_get_type(sym) == S_BOOLEAN)
            newval.tri = yes;
        break;
    case S_STRING:
    case S_HEX:
    case S_INT:
        if (sym->visible != no) {
            sym->flags |= SYMBOL_WRITE;
            if (sym_has_value(sym)) {
                newval.val = sym->user.val;
                break;
            }
        }
        prop = sym_get_default_prop(sym);
        if (prop) {
            struct symbol *ds = prop_get_symbol(prop);
            if (ds) {
                sym->flags |= SYMBOL_WRITE;
                sym_calc_value(ds);
                newval.val = ds->curr.val;
            }
        }
        break;
    default:
        ;
    }

    sym->curr = newval;
    if (sym_is_choice(sym) && newval.tri == yes)
        sym->curr.val = sym_calc_choice(sym);
    sym_validate_range(sym);

    if (memcmp(&oldval, &sym->curr, sizeof(oldval)))
        sym_set_changed(sym);
    if (modules_sym == sym)
        modules_val = modules_sym->curr.tri;

    if (sym_is_choice(sym)) {
        int flags = sym->flags & (SYMBOL_CHANGED | SYMBOL_WRITE);
        prop = sym_get_choice_prop(sym);
        for (e = prop->expr; e; e = e->left.expr) {
            e->right.sym->flags |= flags;
            if (flags & SYMBOL_CHANGED)
                sym_set_changed(e->right.sym);
        }
    }
}

void sym_clear_all_valid(void)
{
    struct symbol *sym;
    int i;

    for_all_symbols(i, sym)
        sym->flags &= ~SYMBOL_VALID;
    sym_change_count++;
    if (modules_sym)
        sym_calc_value(modules_sym);
}

void sym_set_changed(struct symbol *sym)
{
    struct property *prop;

    sym->flags |= SYMBOL_CHANGED;
    for (prop = sym->prop; prop; prop = prop->next) {
        if (prop->menu)
            prop->menu->flags |= MENU_CHANGED;
    }
}

void sym_set_all_changed(void)
{
    struct symbol *sym;
    int i;

    for_all_symbols(i, sym)
        sym_set_changed(sym);
}

bool sym_tristate_within_range(struct symbol *sym, tristate val)
{
    int type = sym_get_type(sym);

    if (sym->visible == no)
        return false;

    if (type != S_BOOLEAN && type != S_TRISTATE)
        return false;

    if (type == S_BOOLEAN && val == mod)
        return false;
    if (sym->visible <= sym->rev_dep.tri)
        return false;
    if (sym_is_choice_value(sym) && sym->visible == yes)
        return val == yes;
    return val >= sym->rev_dep.tri && val <= sym->visible;
}

bool sym_set_tristate_value(struct symbol *sym, tristate val)
{
    tristate oldval = sym_get_tristate_value(sym);

    if (oldval != val && !sym_tristate_within_range(sym, val))
        return false;

    if (sym->flags & SYMBOL_NEW) {
        sym->flags &= ~SYMBOL_NEW;
        sym_set_changed(sym);
    }
    /*
     * setting a choice value also resets the new flag of the choice
     * symbol and all other choice values.
     */
    if (sym_is_choice_value(sym) && val == yes) {
        struct symbol *cs = prop_get_symbol(sym_get_choice_prop(sym));
        struct property *prop;
        struct expr *e;

        cs->user.val = sym;
        cs->flags &= ~SYMBOL_NEW;
        prop = sym_get_choice_prop(cs);
        for (e = prop->expr; e; e = e->left.expr) {
            if (e->right.sym->visible != no)
                e->right.sym->flags &= ~SYMBOL_NEW;
        }
    }

    sym->user.tri = val;
    if (oldval != val) {
        sym_clear_all_valid();
        if (sym == modules_sym)
            sym_set_all_changed();
    }

    return true;
}

tristate sym_toggle_tristate_value(struct symbol *sym)
{
    tristate oldval, newval;

    oldval = newval = sym_get_tristate_value(sym);
    do {
        switch (newval) {
        case no:
            newval = mod;
            break;
        case mod:
            newval = yes;
            break;
        case yes:
            newval = no;
            break;
        }
        if (sym_set_tristate_value(sym, newval))
            break;
    } while (oldval != newval);
    return newval;
}

bool sym_string_valid(struct symbol *sym, const char *str)
{
    signed char ch;

    switch (sym->type) {
    case S_STRING:
        return true;
    case S_INT:
        ch = *str++;
        if (ch == '-')
            ch = *str++;
        if (!isdigit(ch))
            return false;
        if (ch == '0' && *str != 0)
            return false;
        while ((ch = *str++)) {
            if (!isdigit(ch))
                return false;
        }
        return true;
    case S_HEX:
        if (str[0] == '0' && (str[1] == 'x' || str[1] == 'X'))
            str += 2;
        ch = *str++;
        do {
            if (!isxdigit(ch))
                return false;
        } while ((ch = *str++));
        return true;
    case S_BOOLEAN:
    case S_TRISTATE:
        switch (str[0]) {
        case 'y': case 'Y':
        case 'm': case 'M':
        case 'n': case 'N':
            return true;
        }
        return false;
    default:
        return false;
    }
}

bool sym_string_within_range(struct symbol *sym, const char *str)
{
    struct property *prop;
    int val;

    switch (sym->type) {
    case S_STRING:
        return sym_string_valid(sym, str);
    case S_INT:
        if (!sym_string_valid(sym, str))
            return false;
        prop = sym_get_range_prop(sym);
        if (!prop)
            return true;
        val = strtol(str, NULL, 10);
        return val >= sym_get_range_val(prop->expr->left.sym, 10) &&
               val <= sym_get_range_val(prop->expr->right.sym, 10);
    case S_HEX:
        if (!sym_string_valid(sym, str))
            return false;
        prop = sym_get_range_prop(sym);
        if (!prop)
            return true;
        val = strtol(str, NULL, 16);
        return val >= sym_get_range_val(prop->expr->left.sym, 16) &&
               val <= sym_get_range_val(prop->expr->right.sym, 16);
    case S_BOOLEAN:
    case S_TRISTATE:
        switch (str[0]) {
        case 'y': case 'Y':
            return sym_tristate_within_range(sym, yes);
        case 'm': case 'M':
            return sym_tristate_within_range(sym, mod);
        case 'n': case 'N':
            return sym_tristate_within_range(sym, no);
        }
        return false;
    default:
        return false;
    }
}

bool sym_set_string_value(struct symbol *sym, const char *newval)
{
    const char *oldval;
    char *val;
    int size;

    switch (sym->type) {
    case S_BOOLEAN:
    case S_TRISTATE:
        switch (newval[0]) {
        case 'y': case 'Y':
            return sym_set_tristate_value(sym, yes);
        case 'm': case 'M':
            return sym_set_tristate_value(sym, mod);
        case 'n': case 'N':
            return sym_set_tristate_value(sym, no);
        }
        return false;
    default:
        ;
    }

    if (!sym_string_within_range(sym, newval))
        return false;

    if (sym->flags & SYMBOL_NEW) {
        sym->flags &= ~SYMBOL_NEW;
        sym_set_changed(sym);
    }

    oldval = sym->user.val;
    size = strlen(newval) + 1;
    if (sym->type == S_HEX && (newval[0] != '0' || (newval[1] != 'x' && newval[1] != 'X'))) {
        size += 2;
        sym->user.val = val = malloc(size);
        *val++ = '0';
        *val++ = 'x';
    } else if (!oldval || strcmp(oldval, newval))
        sym->user.val = val = malloc(size);
    else
        return true;

    strcpy(val, newval);
    free((void *)oldval);
    sym_clear_all_valid();

    return true;
}

const char *sym_get_string_value(struct symbol *sym)
{
    tristate val;

    switch (sym->type) {
    case S_BOOLEAN:
    case S_TRISTATE:
        val = sym_get_tristate_value(sym);
        switch (val) {
        case no:
            return "n";
        case mod:
            return "m";
        case yes:
            return "y";
        }
        break;
    default:
        ;
    }
    return (const char *)sym->curr.val;
}

bool sym_is_changable(struct symbol *sym)
{
    return sym->visible > sym->rev_dep.tri;
}

struct symbol *sym_lookup(const char *name, int isconst)
{
    struct symbol *symbol;
    const char *ptr;
    char *new_name;
    int hash = 0;

    if (name) {
        if (name[0] && !name[1]) {
            switch (name[0]) {
            case 'y': return &symbol_yes;
            case 'm': return &symbol_mod;
            case 'n': return &symbol_no;
            }
        }
        for (ptr = name; *ptr; ptr++)
            hash += *ptr;
        hash &= 0xff;

        for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
            if (!strcmp(symbol->name, name)) {
                if ((isconst && symbol->flags & SYMBOL_CONST) ||
                    (!isconst && !(symbol->flags & SYMBOL_CONST)))
                    return symbol;
            }
        }
        new_name = strdup(name);
    } else {
        new_name = NULL;
        hash = 256;
    }

    symbol = malloc(sizeof(*symbol));
    memset(symbol, 0, sizeof(*symbol));
    symbol->name = new_name;
    symbol->type = S_UNKNOWN;
    symbol->flags = SYMBOL_NEW;
    if (isconst)
        symbol->flags |= SYMBOL_CONST;

    symbol->next = symbol_hash[hash];
    symbol_hash[hash] = symbol;

    return symbol;
}

struct symbol *sym_find(const char *name)
{
    struct symbol *symbol = NULL;
    const char *ptr;
    int hash = 0;

    if (!name)
        return NULL;

    if (name[0] && !name[1]) {
        switch (name[0]) {
        case 'y': return &symbol_yes;
        case 'm': return &symbol_mod;
        case 'n': return &symbol_no;
        }
    }
    for (ptr = name; *ptr; ptr++)
        hash += *ptr;
    hash &= 0xff;

    for (symbol = symbol_hash[hash]; symbol; symbol = symbol->next) {
        if (!strcmp(symbol->name, name) &&
            !(symbol->flags & SYMBOL_CONST))
                break;
    }

    return symbol;
}

struct symbol **sym_re_search(const char *pattern)
{
    struct symbol *sym, **sym_arr = NULL;
    int i, cnt, size;
    regex_t re;

    cnt = size = 0;
    /* Skip if empty */
    if (strlen(pattern) == 0)
        return NULL;
    if (regcomp(&re, pattern, REG_EXTENDED|REG_NOSUB|REG_ICASE))
        return NULL;

    for_all_symbols(i, sym) {
        if (sym->flags & SYMBOL_CONST || !sym->name)
            continue;
        if (regexec(&re, sym->name, 0, NULL, 0))
            continue;
        if (cnt + 1 >= size) {
            void *tmp = sym_arr;
            size += 16;
            sym_arr = realloc(sym_arr, size * sizeof(struct symbol *));
            if (!sym_arr) {
                free(tmp);
                return NULL;
            }
        }
        sym_arr[cnt++] = sym;
    }
    if (sym_arr)
        sym_arr[cnt] = NULL;
    regfree(&re);

    return sym_arr;
}


struct symbol *sym_check_deps(struct symbol *sym);

static struct symbol *sym_check_expr_deps(struct expr *e)
{
    struct symbol *sym;

    if (!e)
        return NULL;
    switch (e->type) {
    case E_OR:
    case E_AND:
        sym = sym_check_expr_deps(e->left.expr);
        if (sym)
            return sym;
        return sym_check_expr_deps(e->right.expr);
    case E_NOT:
        return sym_check_expr_deps(e->left.expr);
    case E_EQUAL:
    case E_UNEQUAL:
        sym = sym_check_deps(e->left.sym);
        if (sym)
            return sym;
        return sym_check_deps(e->right.sym);
    case E_SYMBOL:
        return sym_check_deps(e->left.sym);
    default:
        break;
    }
    printf("Oops! How to check %d?\n", e->type);
    return NULL;
}

struct symbol *sym_check_deps(struct symbol *sym)
{
    struct symbol *sym2;
    struct property *prop;

    if (sym->flags & SYMBOL_CHECK) {
        printf("Warning! Found recursive dependency: %s", sym->name);
        return sym;
    }
    if (sym->flags & SYMBOL_CHECKED)
        return NULL;

    sym->flags |= (SYMBOL_CHECK | SYMBOL_CHECKED);
    sym2 = sym_check_expr_deps(sym->rev_dep.expr);
    if (sym2)
        goto out;

    for (prop = sym->prop; prop; prop = prop->next) {
        if (prop->type == P_CHOICE || prop->type == P_SELECT)
            continue;
        sym2 = sym_check_expr_deps(prop->visible.expr);
        if (sym2)
            goto out;
        if (prop->type != P_DEFAULT || sym_is_choice(sym))
            continue;
        sym2 = sym_check_expr_deps(prop->expr);
        if (sym2)
            goto out;
    }
out:
    if (sym2) {
        printf(" %s", sym->name);
        if (sym2 == sym) {
            printf("\n");
            sym2 = NULL;
        }
    }
    sym->flags &= ~SYMBOL_CHECK;
    return sym2;
}

struct property *prop_alloc(enum prop_type type, struct symbol *sym)
{
    struct property *prop;
    struct property **propp;

    prop = malloc(sizeof(*prop));
    memset(prop, 0, sizeof(*prop));
    prop->type = type;
    prop->sym = sym;
    prop->file = current_file;
    prop->lineno = zconf_lineno();

    /* append property to the prop list of symbol */
    if (sym) {
        for (propp = &sym->prop; *propp; propp = &(*propp)->next)
            ;
        *propp = prop;
    }

    return prop;
}

struct symbol *prop_get_symbol(struct property *prop)
{
    if (prop->expr && (prop->expr->type == E_SYMBOL ||
               prop->expr->type == E_CHOICE))
        return prop->expr->left.sym;
    return NULL;
}

const char *prop_get_type_name(enum prop_type type)
{
    switch (type) {
    case P_PROMPT:
        return "prompt";
    case P_COMMENT:
        return "comment";
    case P_MENU:
        return "menu";
    case P_DEFAULT:
        return "default";
    case P_CHOICE:
        return "choice";
    case P_SELECT:
        return "select";
    case P_RANGE:
        return "range";
    case P_UNKNOWN:
        break;
    }
    return "unknown";
}