#ifndef CONNECT___NCBI_CONNSSL__H
#define CONNECT___NCBI_CONNSSL__H

/* $Id: ncbi_connssl.h,v 1.4 2015/04/28 18:09:18 kazimird Exp $
 * ===========================================================================
 *
 *                            PUBLIC DOMAIN NOTICE
 *               National Center for Biotechnology Information
 *
 *  This software/database is a "United States Government Work" under the
 *  terms of the United States Copyright Act.  It was written as part of
 *  the author's official duties as a United States Government employee and
 *  thus cannot be copyrighted.  This software/database is freely available
 *  to the public for use. The National Library of Medicine and the U.S.
 *  Government have not placed any restriction on its use or reproduction.
 *
 *  Although all reasonable efforts have been taken to ensure the accuracy
 *  and reliability of the software and data, the NLM and the U.S.
 *  Government do not and cannot warrant the performance or results that
 *  may be obtained by using this software or data. The NLM and the U.S.
 *  Government disclaim all warranties, express or implied, including
 *  warranties of performance, merchantability or fitness for any particular
 *  purpose.
 *
 *  Please cite the author in any work or product based on this material.
 *
 * ===========================================================================
 *
 * Author:  Anton Lavrentiev
 *
 * @file
 * File Description:
 *   Formal definition of a simple SSL API.
 *
 */

#include "ncbi_socketp.h"


#ifdef __cplusplus
extern "C" {
#endif


typedef enum {
    eNcbiCred_GnuTls = 0x484FFB94
} ENcbiCred;


struct SNcbiCred {
    ENcbiCred type;
    void*     data;
};


/* Read up to "size" bytes into buffer "buf", and return the number of bytes
 * actually read via the "done" pointer (must be non-null, on call "*done"==0).
 * The call is allowed to log the transaction data if "logdata" is non-zero.
 * The call is always allowed to log errors (regardless of the last parameter).
 * Return:
 *  eIO_Success if "*done" != 0 or if EOF encountered ("*done" == 0 then);
 *  eIO_Timeout if no data obtained within a preset time allowance;
 *  eIO_Unknown if an error (usually, recoverable) occurred;
 *  eIO_Closed if a non-recoverable error occurred;
 *  other errors per their applicability.
 */
typedef EIO_Status  (*FSSLPull)  (SOCK sock,       void* buf,  size_t size,
                                  size_t* done, int/*bool*/ logdata);

/* Write up to "size" bytes of "data", and return the number of bytes
 * actually written via the "done" pointer (m.b. non-null, on call "*done"==0).
 * The call is allowed to log the transaction data if "logdata" is non-zero.
 * The call is always allowed to log errors (regardless of the last parameter).
 * Return:
 *  eIO_Success iff "*done" != 0;
 *  eIO_Closed if non-recoverable error;
 *  other error code if no data can be written.
 */
typedef EIO_Status  (*FSSLPush)  (SOCK sock, const void* data, size_t size,
                                  size_t* done, int/*bool*/ logdata);


typedef EIO_Status  (*FSSLInit)  (FSSLPull pull, FSSLPush push);
typedef void*       (*FSSLCreate)(ESOCK_Side side, SOCK sock,
                                  NCBI_CRED cred, int* error);
typedef EIO_Status  (*FSSLOpen)  (void* session, int* error, char** desc);

/* See FSSLPull for behavior.  When non-eIO_Success code gets returned,
 * the call must set "*error" to indicate specific problem.  The "*error" may
 * be left unset (and thus, will be ignored) when eIO_Success gets returned.
 */
typedef EIO_Status  (*FSSLRead)  (void* session,       void* buf,  size_t size,
                                  size_t* done,  int* error);
/* See FSSLPush for behavior.  When non-eIO_Success code gets returned,
 * the call must set "*error" to indicate specific problem.  The "*error" may
 * be left unset (and thus, will be ignored) when eIO_Success gets returned.
 */
typedef EIO_Status  (*FSSLWrite) (void* session, const void* data, size_t size,
                                  size_t* done,  int* error);
typedef EIO_Status  (*FSSLClose) (void* session, int how, int* error);
typedef void        (*FSSLDelete)(void* session);
typedef void        (*FSSLExit)  (void);
typedef const char* (*FSSLError) (void* session, int  error);


/* Table of "virtual functions"
 */
struct SOCKSSL_struct {
    FSSLInit   Init;
    FSSLCreate Create;
    FSSLOpen   Open;
    FSSLRead   Read;
    FSSLWrite  Write;
    FSSLClose  Close;
    FSSLDelete Delete;
    FSSLExit   Exit;
    FSSLError  Error;
};


#ifdef __cplusplus
}  /* extern "C" */
#endif


/* @} */

#endif /* CONNECT___NCBI_CONNSSL__H */
