static int select_server_ctx(SSL *s, void *arg, int ignore)
{
    const char *servername = SSL_get_servername(s, TLSEXT_NAMETYPE_host_name);
    HANDSHAKE_EX_DATA *ex_data =
        (HANDSHAKE_EX_DATA*)(SSL_get_ex_data(s, ex_data_idx));
    if (servername == NULL) {
        ex_data->servername = SSL_TEST_SERVERNAME_SERVER1;
        return SSL_TLSEXT_ERR_NOACK;
    }
    if (strcmp(servername, "server2") == 0) {
        SSL_CTX *new_ctx = (SSL_CTX*)arg;
        SSL_set_SSL_CTX(s, new_ctx);
        SSL_clear_options(s, 0xFFFFFFFFL);
        SSL_set_options(s, SSL_CTX_get_options(new_ctx));
        ex_data->servername = SSL_TEST_SERVERNAME_SERVER2;
        return SSL_TLSEXT_ERR_OK;
    } else if (strcmp(servername, "server1") == 0) {
        ex_data->servername = SSL_TEST_SERVERNAME_SERVER1;
        return SSL_TLSEXT_ERR_OK;
    } else if (ignore) {
        ex_data->servername = SSL_TEST_SERVERNAME_SERVER1;
        return SSL_TLSEXT_ERR_NOACK;
    } else {
        return SSL_TLSEXT_ERR_ALERT_FATAL;
    }
}
['static int select_server_ctx(SSL *s, void *arg, int ignore)\n{\n    const char *servername = SSL_get_servername(s, TLSEXT_NAMETYPE_host_name);\n    HANDSHAKE_EX_DATA *ex_data =\n        (HANDSHAKE_EX_DATA*)(SSL_get_ex_data(s, ex_data_idx));\n    if (servername == NULL) {\n        ex_data->servername = SSL_TEST_SERVERNAME_SERVER1;\n        return SSL_TLSEXT_ERR_NOACK;\n    }\n    if (strcmp(servername, "server2") == 0) {\n        SSL_CTX *new_ctx = (SSL_CTX*)arg;\n        SSL_set_SSL_CTX(s, new_ctx);\n        SSL_clear_options(s, 0xFFFFFFFFL);\n        SSL_set_options(s, SSL_CTX_get_options(new_ctx));\n        ex_data->servername = SSL_TEST_SERVERNAME_SERVER2;\n        return SSL_TLSEXT_ERR_OK;\n    } else if (strcmp(servername, "server1") == 0) {\n        ex_data->servername = SSL_TEST_SERVERNAME_SERVER1;\n        return SSL_TLSEXT_ERR_OK;\n    } else if (ignore) {\n        ex_data->servername = SSL_TEST_SERVERNAME_SERVER1;\n        return SSL_TLSEXT_ERR_NOACK;\n    } else {\n        return SSL_TLSEXT_ERR_ALERT_FATAL;\n    }\n}', 'const char *SSL_get_servername(const SSL *s, const int type)\n{\n    if (type != TLSEXT_NAMETYPE_host_name)\n        return NULL;\n    return s->session && !s->ext.hostname ?\n        s->session->ext.hostname : s->ext.hostname;\n}', 'void *SSL_get_ex_data(const SSL *s, int idx)\n{\n    return (CRYPTO_get_ex_data(&s->ex_data, idx));\n}', 'void *CRYPTO_get_ex_data(const CRYPTO_EX_DATA *ad, int idx)\n{\n    if (ad->sk == NULL || idx >= sk_void_num(ad->sk))\n        return NULL;\n    return sk_void_value(ad->sk, idx);\n}', 'SSL_CTX *SSL_set_SSL_CTX(SSL *ssl, SSL_CTX *ctx)\n{\n    CERT *new_cert;\n    if (ssl->ctx == ctx)\n        return ssl->ctx;\n    if (ctx == NULL)\n        ctx = ssl->session_ctx;\n    new_cert = ssl_cert_dup(ctx->cert);\n    if (new_cert == NULL) {\n        return NULL;\n    }\n    ssl_cert_free(ssl->cert);\n    ssl->cert = new_cert;\n    OPENSSL_assert(ssl->sid_ctx_length <= sizeof(ssl->sid_ctx));\n    if ((ssl->ctx != NULL) &&\n        (ssl->sid_ctx_length == ssl->ctx->sid_ctx_length) &&\n        (memcmp(ssl->sid_ctx, ssl->ctx->sid_ctx, ssl->sid_ctx_length) == 0)) {\n        ssl->sid_ctx_length = ctx->sid_ctx_length;\n        memcpy(&ssl->sid_ctx, &ctx->sid_ctx, sizeof(ssl->sid_ctx));\n    }\n    SSL_CTX_up_ref(ctx);\n    SSL_CTX_free(ssl->ctx);\n    ssl->ctx = ctx;\n    return ssl->ctx;\n}', 'unsigned long SSL_clear_options(SSL *s, unsigned long op)\n{\n    return s->options &= ~op;\n}', 'unsigned long SSL_CTX_get_options(const SSL_CTX *ctx)\n{\n    return ctx->options;\n}', 'unsigned long SSL_set_options(SSL *s, unsigned long op)\n{\n    return s->options |= op;\n}']