1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/io/rx_link.c	Sat Feb 20 21:18:28 2010 -0800
     1.3 @@ -0,0 +1,227 @@
     1.4 +/*
     1.5 + * $Id: rx_link.c,v 1.7 2004/02/01 08:17:12 hipnod Exp $
     1.6 + *
     1.7 + * Copyright (C) 2003 giFT project (gift.sourceforge.net)
     1.8 + *
     1.9 + * This program is free software; you can redistribute it and/or modify it
    1.10 + * under the terms of the GNU General Public License as published by the
    1.11 + * Free Software Foundation; either version 2, or (at your option) any
    1.12 + * later version.
    1.13 + *
    1.14 + * This program is distributed in the hope that it will be useful, but
    1.15 + * WITHOUT ANY WARRANTY; without even the implied warranty of
    1.16 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    1.17 + * General Public License for more details.
    1.18 + */
    1.19 +
    1.20 +#include "gt_gnutella.h"
    1.21 +
    1.22 +#include "rx_layer.h"
    1.23 +#include "rx_link.h"
    1.24 +
    1.25 +/*****************************************************************************/
    1.26 +
    1.27 +struct rx_link
    1.28 +{
    1.29 +	/* TODO when the tx stack is implemented also
    1.30 +	 * right now cleanup is too hard */
    1.31 +#if 0
    1.32 +	struct io_source  *ios;
    1.33 +#endif
    1.34 +	TCPC              *c;
    1.35 +	input_id           id;
    1.36 +};
    1.37 +
    1.38 +/*****************************************************************************/
    1.39 +
    1.40 +/* Some macros for readability */
    1.41 +
    1.42 +#define RX_LINK(rx) \
    1.43 +	((struct rx_link *)((rx)->udata))
    1.44 +
    1.45 +#define IO_SOURCE(rx_link) \
    1.46 +	((rx_link)->ios)
    1.47 +
    1.48 +/*****************************************************************************/
    1.49 +
    1.50 +/* TODO: implement cached allocation */
    1.51 +#define RX_LINK_BUFSIZE      512
    1.52 +
    1.53 +/*
    1.54 + * This implementation is for bootstrapping the code onto
    1.55 + * the present system.
    1.56 + *
    1.57 + * The low-level details of what we are actually reading
    1.58 + * from should be abstracted away.
    1.59 + */
    1.60 +static void read_data (int fd, input_id id, struct rx_layer *rx)
    1.61 +{
    1.62 +	struct rx_link   *rx_link = RX_LINK(rx);
    1.63 +	struct io_buf    *io_buf;
    1.64 +	ssize_t           n;
    1.65 +
    1.66 +	/* we're processing data, we'd better be enabled */
    1.67 +	assert (rx->enabled);
    1.68 +
    1.69 +	if (!(io_buf = io_buf_new (RX_LINK_BUFSIZE)))
    1.70 +	{
    1.71 +		gt_rx_stack_abort (rx->stack);
    1.72 +		return;
    1.73 +	}
    1.74 +
    1.75 +	if ((n = tcp_recv (rx_link->c, io_buf_write_ptr (io_buf), 
    1.76 +	                   RX_LINK_BUFSIZE)) <= 0)
    1.77 +	{
    1.78 +		if (IO_DEBUG)
    1.79 +		{
    1.80 +			if (n < 0)
    1.81 +				GT->DBGSOCK (GT, rx_link->c, "recv error: %s", GIFT_NETERROR());
    1.82 +			else
    1.83 +				GT->DBGSOCK (GT, rx_link->c, "recv error: socket closed");
    1.84 +		}
    1.85 +
    1.86 +		io_buf_free (io_buf);
    1.87 +		gt_rx_stack_abort (rx->stack);
    1.88 +		return;
    1.89 +	}
    1.90 +
    1.91 +	/* set the data as having been read */
    1.92 +	io_buf_push (io_buf, n);
    1.93 +
    1.94 +	/*
    1.95 +	 * Pass the data up the stack.
    1.96 +	 */
    1.97 +	gt_rx_layer_recv (rx, io_buf);
    1.98 +}
    1.99 +
   1.100 +#if 0
   1.101 +/*
   1.102 + * Receive data from the I/O source, and pass it up the stack
   1.103 + */
   1.104 +static void recv_data (struct io_source *ios, struct io_buf *io_buf)
   1.105 +{
   1.106 +	struct rx_layer   *rx;
   1.107 +	struct rx_link    *rx_link;
   1.108 +	ssize_t            n;
   1.109 +
   1.110 +    rx      = ios->recv_data;
   1.111 +	rx_link = RX_LINK(rx);
   1.112 +
   1.113 +	/*
   1.114 +	 * Pass the data to an upper layer.
   1.115 +	 */
   1.116 +	gt_rx_layer_recv (rx, io_buf);
   1.117 +
   1.118 +	/*
   1.119 +	 * ?? we have to free io_buf here ?? No.
   1.120 +	 * gtk-gnutella passes off responsibility to the upper layers,
   1.121 +	 * but why..
   1.122 +	 */
   1.123 +#if 0
   1.124 +	return n;
   1.125 +#endif
   1.126 +	/*
   1.127 +	 * Think i may understand why gtk-gnutella does it that way now:
   1.128 +	 * in the partial packet case there may be unread data on the packet,
   1.129 +	 * so we have to store that partial packet data in the intermediate
   1.130 +	 * layers.
   1.131 +	 *
   1.132 +	 * I still wonder if its possible to use a static buffer at each layer
   1.133 +	 * though...
   1.134 +	 */
   1.135 +}
   1.136 +#endif
   1.137 +
   1.138 +static void init_input (struct rx_layer *rx, struct rx_link *rx_link)
   1.139 +{
   1.140 +	assert (rx_link->id == 0);
   1.141 +	rx_link->id = input_add (rx_link->c->fd, rx, INPUT_READ,
   1.142 +	                         (InputCallback)read_data, 0);
   1.143 +}
   1.144 +
   1.145 +static void free_input (struct rx_layer *rx, struct rx_link *rx_link)
   1.146 +{
   1.147 +	/*
   1.148 +	 * This could be called multiple times on cleanup,
   1.149 +	 * so we don't assert the id is 0 here.
   1.150 +	 */
   1.151 +	if (rx_link->id)
   1.152 +	{
   1.153 +		input_remove (rx_link->id);
   1.154 +		rx_link->id = 0;
   1.155 +	}
   1.156 +}
   1.157 +
   1.158 +static void rx_link_enable (struct rx_layer *rx)
   1.159 +{
   1.160 +	struct rx_link *rx_link = RX_LINK(rx);
   1.161 +
   1.162 +#if 0
   1.163 +	/* set the callback for getting data */
   1.164 +	io_source_enable (IO_SOURCE(rx_link), IO_SOURCE_OP_RECV, recv_data, rx);
   1.165 +#endif
   1.166 +
   1.167 +	init_input (rx, rx_link);
   1.168 +}
   1.169 +
   1.170 +static void rx_link_disable (struct rx_layer *rx)
   1.171 +{
   1.172 +	struct rx_link *rx_link = RX_LINK(rx);
   1.173 +
   1.174 +#if 0
   1.175 +	io_source_disable (IO_SOURCE(rx_link), IO_SOURCE_OP_RECV);
   1.176 +#endif
   1.177 +	free_input (rx, rx_link);
   1.178 +}
   1.179 +
   1.180 +static BOOL rx_link_init (struct rx_layer *rx, void *udata)
   1.181 +{
   1.182 +	struct rx_link *rx_link;
   1.183 +	TCPC           *c = (TCPC *) udata;  /* ewwww */
   1.184 +
   1.185 +	if (!(rx_link = NEW (struct rx_link)))
   1.186 +		return FALSE;
   1.187 +
   1.188 +	/* store the connection which we get from the upper layer...gross */
   1.189 +	rx_link->c = c;
   1.190 +
   1.191 +	/* store our data in the rx structure */
   1.192 +	rx->udata = rx_link;
   1.193 +
   1.194 +	return TRUE;
   1.195 +}
   1.196 +
   1.197 +static void rx_link_destroy (struct rx_layer *rx)
   1.198 +{
   1.199 +	struct rx_link *rx_link = RX_LINK(rx);
   1.200 +
   1.201 +	/*
   1.202 +	 * rx_link_disable() should be called first
   1.203 +	 */
   1.204 +	assert (rx_link->id == 0);
   1.205 +
   1.206 +	/*
   1.207 +	 * We would free the connection here, but its shared with
   1.208 +	 * a GtNode that frees it also at the moment.
   1.209 +	 */
   1.210 +#if 0
   1.211 +	tcp_close (rx->c);
   1.212 +#endif
   1.213 +
   1.214 +#if 0
   1.215 +	io_source_free (rx_link->ios);
   1.216 +#endif
   1.217 +
   1.218 +	FREE (rx_link);
   1.219 +}
   1.220 +
   1.221 +/*****************************************************************************/
   1.222 +
   1.223 +struct rx_layer_ops gt_rx_link_ops =
   1.224 +{
   1.225 +	rx_link_init,
   1.226 +	rx_link_destroy,
   1.227 +	rx_link_enable,
   1.228 +	rx_link_disable,
   1.229 +	NULL,           /* rx_link_recv */
   1.230 +};