symbol.c

busybox最新版的源码:学习和应用的好东东,多的不说了,大家看后再说吧

/*
 * Copyright (C) 2002 Roman Zippel <[e-mail]>
 * 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;