/*
 * This file is part of the SSH Library
 *
 * Copyright (c) 2009 by Aris Adamantiadis
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#ifndef CHANNELS_H_
#define CHANNELS_H_
#include "libssh/priv.h"

#ifdef __cplusplus
extern "C" {
#endif

/**  @internal
 * Describes the different possible states in a
 * outgoing (client) channel request
 */
enum ssh_channel_request_state_e {
	/** No request has been made */
	SSH_CHANNEL_REQ_STATE_NONE = 0,
	/** A request has been made and answer is pending */
	SSH_CHANNEL_REQ_STATE_PENDING,
	/** A request has been replied and accepted */
	SSH_CHANNEL_REQ_STATE_ACCEPTED,
	/** A request has been replied and refused */
	SSH_CHANNEL_REQ_STATE_DENIED,
	/** A request has been replied and an error happened */
	SSH_CHANNEL_REQ_STATE_ERROR
};

enum ssh_channel_state_e {
  SSH_CHANNEL_STATE_NOT_OPEN = 0,
  SSH_CHANNEL_STATE_OPENING,
  SSH_CHANNEL_STATE_OPEN_DENIED,
  SSH_CHANNEL_STATE_OPEN,
  SSH_CHANNEL_STATE_CLOSED
};

/* The channel has been closed by the remote side */
#define SSH_CHANNEL_FLAG_CLOSED_REMOTE 0x0001

/* The channel has been closed locally */
#define SSH_CHANNEL_FLAG_CLOSED_LOCAL 0x0002

/* The channel has been freed by the calling program */
#define SSH_CHANNEL_FLAG_FREED_LOCAL 0x0004

/* the channel has not yet been bound to a remote one */
#define SSH_CHANNEL_FLAG_NOT_BOUND 0x0008

struct ssh_channel_struct {
    ssh_session session; /* SSH_SESSION pointer */
    uint32_t local_channel;
    uint32_t local_window;
    int local_eof;
    uint32_t local_maxpacket;

    uint32_t remote_channel;
    uint32_t remote_window;
    int remote_eof; /* end of file received */
    uint32_t remote_maxpacket;
    enum ssh_channel_state_e state;
    int delayed_close;
    int flags;
    ssh_buffer stdout_buffer;
    ssh_buffer stderr_buffer;
    void *userarg;
    int exit_status;
    enum ssh_channel_request_state_e request_state;
    struct ssh_list *callbacks; /* list of ssh_channel_callbacks */

    /* counters */
    ssh_counter counter;
};

SSH_PACKET_CALLBACK(ssh_packet_channel_open_conf);
SSH_PACKET_CALLBACK(ssh_packet_channel_open_fail);
SSH_PACKET_CALLBACK(ssh_packet_channel_success);
SSH_PACKET_CALLBACK(ssh_packet_channel_failure);
SSH_PACKET_CALLBACK(ssh_request_success);
SSH_PACKET_CALLBACK(ssh_request_denied);

SSH_PACKET_CALLBACK(channel_rcv_change_window);
SSH_PACKET_CALLBACK(channel_rcv_eof);
SSH_PACKET_CALLBACK(channel_rcv_close);
SSH_PACKET_CALLBACK(channel_rcv_request);
SSH_PACKET_CALLBACK(channel_rcv_data);

int channel_default_bufferize(ssh_channel channel,
                              void *data, uint32_t len,
                              bool is_stderr);
int ssh_channel_flush(ssh_channel channel);
uint32_t ssh_channel_new_id(ssh_session session);
ssh_channel ssh_channel_from_local(ssh_session session, uint32_t id);
void ssh_channel_do_free(ssh_channel channel);
int ssh_global_request(ssh_session session,
                       const char *request,
                       ssh_buffer buffer,
                       int reply);

#ifdef __cplusplus
}
#endif

#endif /* CHANNELS_H_ */
