SSL: clear error queue after OPENSSL_init_ssl(). The function may leave error in the error queue while returning success, e.g., when taking a DSO reference to itself as of OpenSSL 1.1.0d: https://git.openssl.org/?p=openssl.git;a=commit;h=4af9f7f Notably, this fixes alert seen with statically linked OpenSSL on some platforms. While here, check OPENSSL_init_ssl() return value.

/*
 * Copyright (C) Maxim Dounin
 * Copyright (C) Nginx, Inc.
 */


#include <ngx_config.h>
#include <ngx_core.h>


#if (NGX_HAVE_DLOPEN)

char *
ngx_dlerror(void)
{
    char  *err;

    err = (char *) dlerror();

    if (err == NULL) {
        return "";
    }

    return err;
}

#endif