Function variable_add

scripts/config/preprocess.c:279–322

}

void variable_add(const char *name, const char *value,
		  enum variable_flavor flavor)
{
	struct variable *v;
	char *new_value;
	bool append = false;

	v = variable_lookup(name);
	if (v) {
		/* For defined variables, += inherits the existing flavor */
		if (flavor == VAR_APPEND) {
			flavor = v->flavor;
			append = true;
		} else {
			free(v->value);
		}
	} else {
		/* For undefined variables, += assumes the recursive flavor */
		if (flavor == VAR_APPEND)
			flavor = VAR_RECURSIVE;

		v = xmalloc(sizeof(*v));
		v->name = xstrdup(name);
		v->exp_count = 0;
		list_add_tail(&v->node, &variable_list);
	}

	v->flavor = flavor;

	if (flavor == VAR_SIMPLE)
		new_value = expand_string(value);
	else
		new_value = xstrdup(value);

	if (append) {
		v->value = xrealloc(v->value,
				    strlen(v->value) + strlen(new_value) + 2);
		strcat(v->value, " ");
		strcat(v->value, new_value);
		free(new_value);
	} else {
		v->value = new_value;
	}
}

static void variable_del(struct variable *v)
{