OSSL_LIB_CTX

OSSL_LIB_CTX(3)                      OpenSSL                     OSSL_LIB_CTX(3)



NAME
       OSSL_LIB_CTX, OSSL_LIB_CTX_new, OSSL_LIB_CTX_free,
       OSSL_LIB_CTX_load_config, OSSL_LIB_CTX_set0_default - OpenSSL library
       context

SYNOPSIS
        #include <openssl/crypto.h>

        typedef struct ossl_lib_ctx_st OSSL_LIB_CTX;

        OSSL_LIB_CTX *OSSL_LIB_CTX_new(void);
        int OSSL_LIB_CTX_load_config(OSSL_LIB_CTX *ctx, const char *config_file);
        void OSSL_LIB_CTX_free(OSSL_LIB_CTX *ctx);
        OSSL_LIB_CTX *OSSL_LIB_CTX_set0_default(OSSL_LIB_CTX *ctx);

DESCRIPTION
       OSSL_LIB_CTX is an internal OpenSSL library context type.  Applications
       may allocate their own, but may also use NULL to use a default context
       with functions that take an OSSL_LIB_CTX argument.

       When a non default library context is in use care should be taken with
       multi-threaded applications to properly clean up thread local resources
       before the OSSL_LIB_CTX is freed.  See OPENSSL_thread_stop_ex(3) for more
       information.

       OSSL_LIB_CTX_new() creates a new OpenSSL library context.

       OSSL_LIB_CTX_load_config() loads a configuration file using the given
       "ctx".  This can be used to associate a library context with providers
       that are loaded from a configuration.

       OSSL_LIB_CTX_free() frees the given ctx, unless it happens to be the
       default OpenSSL library context.

       OSSL_LIB_CTX_set0_default() sets the default OpenSSL library context to
       be ctx in the current thread.  The previous default library context is
       returned.  Care should be taken by the caller to restore the previous
       default library context with a subsequent call of this function.

       Care should be taken when changing the default library context and
       starting async jobs (see ASYNC_start_job(3)), as the default library
       context when the job is started will be used throughout the lifetime of
       an async job, no matter how the calling thread makes further default
       library context changes in the mean time.  This means that the calling
       thread must not free the library context that was the default at the
       start of the async job before that job has finished.

RETURN VALUES
       OSSL_LIB_CTX_new() and OSSL_LIB_CTX_set0_default() return a library
       context pointer on success, or NULL on error.

       OSSL_LIB_CTX_free() doesn't return any value.

HISTORY
       OSSL_LIB_CTX, OSSL_LIB_CTX_new(), OSSL_LIB_CTX_load_config(),
       OSSL_LIB_CTX_free() and OSSL_LIB_CTX_set0_default() were added in OpenSSL
       3.0.

COPYRIGHT
       Copyright 2019-2020 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>.



3.0.0-alpha12                      2021-02-18                    OSSL_LIB_CTX(3)