/* * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved. * * Licensed under the Apache License 2.0 (the "License"). You may not use * this file except in compliance with the License. You can obtain a copy * in the file LICENSE in the source distribution or at * https://www.openssl.org/source/license.html */ #ifndef OSSL_INTERNAL_THREAD_ONCE_H # define OSSL_INTERNAL_THREAD_ONCE_H # pragma once # include <openssl/crypto.h> /* * Initialisation of global data should never happen via "RUN_ONCE" inside the * FIPS module. Global data should instead always be associated with a specific * OSSL_LIB_CTX object. In this way data will get cleaned up correctly when the * module gets unloaded. */ # if !defined(FIPS_MODULE) || defined(ALLOW_RUN_ONCE_IN_FIPS) /* * DEFINE_RUN_ONCE: Define an initialiser function that should be run exactly * once. It takes no arguments and returns an int result (1 for success or * 0 for failure). Typical usage might be: * * DEFINE_RUN_ONCE(myinitfunc) * { * do_some_initialisation(); * if (init_is_successful()) * return 1; * * return 0; * } */ # define DEFINE_RUN_ONCE(init) \ static int init(void); \ int init##_ossl_ret_ = 0; \ void init##_ossl_(void) \ { \ init##_ossl_ret_ = init(); \ } \ static int init(void) /* * DECLARE_RUN_ONCE: Declare an initialiser function that should be run exactly * once that has been defined in another file via DEFINE_RUN_ONCE(). */ # define DECLARE_RUN_ONCE(init) \ extern int init##_ossl_ret_; \ void init##_ossl_(void); /* * DEFINE_RUN_ONCE_STATIC: Define an initialiser function that should be run * exactly once. This function will be declared as static within the file. It * takes no arguments and returns an int result (1 for success or 0 for * failure). Typical usage might be: * * DEFINE_RUN_ONCE_STATIC(myinitfunc) * { * do_some_initialisation(); * if (init_is_successful()) * return 1; * * return 0; * } */ # define DEFINE_RUN_ONCE_STATIC(init) \ static int init(void); \ static int init##_ossl_ret_ = 0; \ static void init##_ossl_(void) \ { \ init##_ossl_ret_ = init(); \ } \ static int init(void) /* * DEFINE_RUN_ONCE_STATIC_ALT: Define an alternative initialiser function. This * function will be declared as static within the file. It takes no arguments * and returns an int result (1 for success or 0 for failure). An alternative * initialiser function is expected to be associated with a primary initialiser * function defined via DEFINE_ONCE_STATIC where both functions use the same * CRYPTO_ONCE object to synchronise. Where an alternative initialiser function * is used only one of the primary or the alternative initialiser function will * ever be called - and that function will be called exactly once. Definition * of an alternative initialiser function MUST occur AFTER the definition of the * primary initialiser function. * * Typical usage might be: * * DEFINE_RUN_ONCE_STATIC(myinitfunc) * { * do_some_initialisation(); * if (init_is_successful()) * return 1; * * return 0; * } * * DEFINE_RUN_ONCE_STATIC_ALT(myaltinitfunc, myinitfunc) * { * do_some_alternative_initialisation(); * if (init_is_successful()) * return 1; * * return 0; * } */ # define DEFINE_RUN_ONCE_STATIC_ALT(initalt, init) \ static int initalt(void); \ static void initalt##_ossl_(void) \ { \ init##_ossl_ret_ = initalt(); \ } \ static int initalt(void) /* * RUN_ONCE - use CRYPTO_THREAD_run_once, and check if the init succeeded * @once: pointer to static object of type CRYPTO_ONCE * @init: function name that was previously given to DEFINE_RUN_ONCE, * DEFINE_RUN_ONCE_STATIC or DECLARE_RUN_ONCE. This function * must return 1 for success or 0 for failure. * * The return value is 1 on success (*) or 0 in case of error. * * (*) by convention, since the init function must return 1 on success. */ # define RUN_ONCE(once, init) \ (CRYPTO_THREAD_run_once(once, init##_ossl_) ? init##_ossl_ret_ : 0) /* * RUN_ONCE_ALT - use CRYPTO_THREAD_run_once, to run an alternative initialiser * function and check if that initialisation succeeded * @once: pointer to static object of type CRYPTO_ONCE * @initalt: alternative initialiser function name that was previously given to * DEFINE_RUN_ONCE_STATIC_ALT. This function must return 1 for * success or 0 for failure. * @init: primary initialiser function name that was previously given to * DEFINE_RUN_ONCE_STATIC. This function must return 1 for success or * 0 for failure. * * The return value is 1 on success (*) or 0 in case of error. * * (*) by convention, since the init function must return 1 on success. */ # define RUN_ONCE_ALT(once, initalt, init) \ (CRYPTO_THREAD_run_once(once, initalt##_ossl_) ? init##_ossl_ret_ : 0) # endif /* FIPS_MODULE */ #endif /* OSSL_INTERNAL_THREAD_ONCE_H */