1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/io/rx_inflate.c	Sat Feb 20 21:18:28 2010 -0800
     1.3 @@ -0,0 +1,192 @@
     1.4 +/*
     1.5 + * $Id: rx_inflate.c,v 1.10 2004/04/05 07:56:54 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_stack.h"
    1.23 +#include "rx_layer.h"
    1.24 +
    1.25 +#include <zlib.h>
    1.26 +
    1.27 +/*****************************************************************************/
    1.28 +
    1.29 +/* this is small for testing purposes */
    1.30 +#define    RX_INFLATE_BUFSIZE   256
    1.31 +
    1.32 +#define RX_INFLATE(rx) \
    1.33 +	((struct rx_inflate *) (((rx)->udata)))
    1.34 +
    1.35 +struct rx_inflate
    1.36 +{
    1.37 +	z_stream       z;
    1.38 +	BOOL           init_done;
    1.39 +};
    1.40 +
    1.41 +/*****************************************************************************/
    1.42 +
    1.43 +static BOOL rx_inflate_init (struct rx_layer *rx, void *udata)
    1.44 +{
    1.45 +	struct rx_inflate *rx_inflate;
    1.46 +
    1.47 +	if (!(rx_inflate = NEW (struct rx_inflate)))
    1.48 +		return FALSE;
    1.49 +
    1.50 +	/* inflateInit() may touch these variables */
    1.51 +	rx_inflate->z.zalloc   = Z_NULL;
    1.52 +	rx_inflate->z.zfree    = Z_NULL;
    1.53 +	rx_inflate->z.opaque   = Z_NULL;
    1.54 +	rx_inflate->z.next_in  = Z_NULL;
    1.55 +	rx_inflate->z.avail_in = 0;
    1.56 +
    1.57 +	if (inflateInit (&rx_inflate->z) != Z_OK)
    1.58 +	{
    1.59 +		gt_rx_stack_abort (rx->stack);
    1.60 +		return FALSE;
    1.61 +	}
    1.62 +
    1.63 +	rx->udata = rx_inflate;
    1.64 +
    1.65 +	rx_inflate->init_done = TRUE;
    1.66 +
    1.67 +	return TRUE;
    1.68 +}
    1.69 +
    1.70 +static void rx_inflate_destroy (struct rx_layer *rx)
    1.71 +{
    1.72 +	struct rx_inflate *rx_inflate = RX_INFLATE(rx);
    1.73 +
    1.74 +	/*
    1.75 +	 * We don't check the error here, there could very well be leftover data
    1.76 +	 * and it would be annoying to print a message every time.
    1.77 +	 */
    1.78 +	inflateEnd (&rx_inflate->z);
    1.79 +	rx_inflate->init_done = FALSE;
    1.80 +
    1.81 +	FREE (rx_inflate);
    1.82 +}
    1.83 +
    1.84 +static void rx_inflate_enable (struct rx_layer *rx)
    1.85 +{
    1.86 +	/* nothing -- we only process data when it comes towards us */
    1.87 +}
    1.88 +
    1.89 +static void rx_inflate_disable (struct rx_layer *rx)
    1.90 +{
    1.91 +	/* nothing */
    1.92 +}
    1.93 +
    1.94 +/*
    1.95 + * Handle the data from the lower layer, decompress it, and pass
    1.96 + * it to the upper layer.
    1.97 + */
    1.98 +static struct io_buf *read_buf (struct rx_layer *rx, struct io_buf *io_buf)
    1.99 +{
   1.100 +	struct rx_inflate *rx_inflate   = RX_INFLATE(rx);
   1.101 +	struct io_buf     *out_msg;
   1.102 +	z_streamp          inz;
   1.103 +	int                ret;
   1.104 +	size_t             uncompressed_size;
   1.105 +	size_t             compressed_read;
   1.106 +	size_t             out_size     = RX_INFLATE_BUFSIZE;
   1.107 +	size_t             avail;
   1.108 +	static size_t      running_cnt  = 0;
   1.109 +	static int         msg_count    = 0;
   1.110 +
   1.111 +	avail = io_buf_read_avail (io_buf);
   1.112 +
   1.113 +	if (avail == 0)
   1.114 +		return NULL;
   1.115 +
   1.116 +	if (!(out_msg = io_buf_new (out_size)))
   1.117 +	{
   1.118 +		GT->dbg (GT, "couldn't allocate memory for recv buf");
   1.119 +		gt_rx_stack_abort (rx->stack);
   1.120 +		return NULL;
   1.121 +	}
   1.122 +
   1.123 +	assert (rx_inflate->init_done);
   1.124 +	inz = &rx_inflate->z;
   1.125 +
   1.126 +	inz->next_in   = io_buf_read_ptr (io_buf);
   1.127 +	inz->avail_in  = avail;
   1.128 +	inz->next_out  = io_buf_write_ptr (out_msg);
   1.129 +	inz->avail_out = out_size;
   1.130 +
   1.131 +	ret = inflate (inz, Z_SYNC_FLUSH);
   1.132 +
   1.133 +	if (ret != Z_OK)
   1.134 +	{
   1.135 +		if (IO_DEBUG)
   1.136 +			GT->dbg (GT, "zlib recv error: %d", ret);
   1.137 +
   1.138 +		gt_rx_stack_abort (rx->stack);
   1.139 +		io_buf_free (out_msg);
   1.140 +		return NULL;
   1.141 +	}
   1.142 +
   1.143 +	uncompressed_size  = out_size - inz->avail_out;
   1.144 +	compressed_read    = avail - inz->avail_in;
   1.145 +
   1.146 +	running_cnt += uncompressed_size;
   1.147 +	if (IO_DEBUG && ++msg_count % 50 == 0)
   1.148 +	{
   1.149 +		GT->dbg (GT, "uncompressed %u bytes", running_cnt);
   1.150 +		running_cnt = 0;
   1.151 +	}
   1.152 +
   1.153 +	/* add the bytes we read to the new messge */
   1.154 +	io_buf_push (out_msg, uncompressed_size);
   1.155 +
   1.156 +	/* pop the old bytes we read off the incoming message */
   1.157 +	io_buf_pop (io_buf, compressed_read);
   1.158 +
   1.159 +	return out_msg;
   1.160 +}
   1.161 +
   1.162 +/*
   1.163 + * Parse the data into buffers, and send it to the upper layers.  packets to
   1.164 + */
   1.165 +static void rx_inflate_recv (struct rx_layer *rx, struct io_buf *io_buf)
   1.166 +{
   1.167 +	struct io_buf   *msg;
   1.168 +
   1.169 +	while (rx->enabled && (msg = read_buf (rx, io_buf)))
   1.170 +	{
   1.171 +		assert (msg != NULL);
   1.172 +		gt_rx_layer_recv (rx, msg);
   1.173 +
   1.174 +		/* 
   1.175 +		 * NOTE: gt_rx_layer_recv() may abort the stack here...  there's not much
   1.176 +		 * we can do about that, but in practice that doesn't happen and we
   1.177 +		 * won't access freed memory because the stack doesn't get freed until
   1.178 +		 * the lowest rx layer is notified of the abort...pretty hacky.
   1.179 +		 */
   1.180 +	}
   1.181 +
   1.182 +	/* we have to free the buffer */
   1.183 +	io_buf_free (io_buf);
   1.184 +}
   1.185 +
   1.186 +/*****************************************************************************/
   1.187 +
   1.188 +struct rx_layer_ops gt_rx_inflate_ops =
   1.189 +{
   1.190 +	rx_inflate_init,
   1.191 +	rx_inflate_destroy,
   1.192 +	rx_inflate_enable,
   1.193 +	rx_inflate_disable,
   1.194 +	rx_inflate_recv,
   1.195 +};