1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/src/gt_share.c	Sat Feb 20 21:18:28 2010 -0800
     1.3 @@ -0,0 +1,384 @@
     1.4 +/*
     1.5 + * $Id: gt_share.c,v 1.35 2004/03/26 11:53:18 hipnod Exp $
     1.6 + *
     1.7 + * Copyright (C) 2001-2003 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 +#include "sha1.h"
    1.22 +
    1.23 +#include "gt_share.h"
    1.24 +#include "gt_share_file.h"
    1.25 +#include "gt_query_route.h"
    1.26 +#include "gt_search.h"
    1.27 +#include "gt_search_exec.h"
    1.28 +
    1.29 +#include "encoding/url.h"
    1.30 +
    1.31 +/******************************************************************************/
    1.32 +
    1.33 +#define  SHARE_DEBUG          gt_config_get_int("share/debug=0")
    1.34 +
    1.35 +/*****************************************************************************/
    1.36 +
    1.37 +/* each share is assigned an index here */
    1.38 +static Dataset *indices;
    1.39 +
    1.40 +/* maps binary sha1 hashes -> FileShares */
    1.41 +static Dataset *sha1_hashes;
    1.42 +
    1.43 +/* stored index of the last index assigned */
    1.44 +static uint32_t index_counter;
    1.45 +
    1.46 +/* whether shares have been completely synchronized yet */
    1.47 +static BOOL     sync_begun;
    1.48 +
    1.49 +/* if shares are currently being synced */
    1.50 +static BOOL     sync_done;
    1.51 +
    1.52 +/******************************************************************************/
    1.53 +
    1.54 +static void add_hash    (FileShare *file);
    1.55 +static void remove_hash (FileShare *file);
    1.56 +
    1.57 +/******************************************************************************/
    1.58 +
    1.59 +/*
    1.60 + * Find the old index, using the SHA1 hash as a key.
    1.61 + */
    1.62 +static uint32_t get_old_index (Hash *hash)
    1.63 +{
    1.64 +	Share   *old_share;
    1.65 +	uint32_t index     = 0;
    1.66 +
    1.67 +	old_share = dataset_lookup (sha1_hashes, hash->data, SHA1_BINSIZE);
    1.68 +	if (old_share != NULL)
    1.69 +	{
    1.70 +		GtShare *gt_share = share_get_udata (old_share, GT->name);
    1.71 +
    1.72 +		if (gt_share)
    1.73 +			index = gt_share->index;
    1.74 +	}
    1.75 +
    1.76 +	return index;
    1.77 +}
    1.78 +
    1.79 +/*
    1.80 + * Find an unused index, but reuse the existing index if possible.
    1.81 + */
    1.82 +static uint32_t get_share_index (Share *share)
    1.83 +{
    1.84 +	Hash     *hash;
    1.85 +	uint32_t  index;
    1.86 +
    1.87 +	if ((hash = share_get_hash (share, "SHA1")) != NULL)
    1.88 +	{
    1.89 +		uint32_t hash_tmp;
    1.90 +
    1.91 +		/* if a Share with the same hash has another index, re-use that one */
    1.92 +		if ((index = get_old_index (hash)) != 0)
    1.93 +			return index;
    1.94 +
    1.95 +		memcpy (&hash_tmp, hash->data, 4);
    1.96 +
    1.97 +		/* use the first 24 bits of the SHA1 hash to seed the file index */
    1.98 +		index_counter = hash_tmp & 0xfffffff;
    1.99 +	}
   1.100 +
   1.101 +	if (!(index = dataset_uniq32 (indices, &index_counter)))
   1.102 +		return 0;
   1.103 +
   1.104 +	return index;
   1.105 +}
   1.106 +
   1.107 +static void add_index (Share *share, GtShare *gt_share)
   1.108 +{
   1.109 +	uint32_t index;
   1.110 +
   1.111 +	if (SHARE_DEBUG)
   1.112 +		GT->dbg (GT, "++[%d]->%s", gt_share->index, gt_share->filename);
   1.113 +
   1.114 +	index = get_share_index (share);
   1.115 +	dataset_insert (&indices, &index, sizeof(index), share, 0);
   1.116 +}
   1.117 +
   1.118 +static void remove_index (Share *share, GtShare *gt_share)
   1.119 +{
   1.120 +	uint32_t index = gt_share->index;
   1.121 +
   1.122 +	assert (index > 0);
   1.123 +
   1.124 +	/*
   1.125 +	 * Check if the index is pointing at a different share.  This case happens
   1.126 +	 * for every Share that is not removed on a resync, due to the weird way
   1.127 +	 * giftd 0.11.x use the new/add/remove/free interface.
   1.128 +	 */
   1.129 +	if (dataset_lookup (indices, &index, sizeof(index)) != share)
   1.130 +		return;
   1.131 +
   1.132 +	if (SHARE_DEBUG)
   1.133 +		GT->dbg (GT, "--[%d]->%s", gt_share->index, gt_share->filename);
   1.134 +
   1.135 +	index = gt_share->index;
   1.136 +	dataset_remove (indices, &index, sizeof(index));
   1.137 +
   1.138 +	if (dataset_length (indices) == 0)
   1.139 +	{
   1.140 +		dataset_clear (indices);
   1.141 +		indices = NULL;
   1.142 +	}
   1.143 +}
   1.144 +
   1.145 +/******************************************************************************/
   1.146 +
   1.147 +/* TODO: This duplicates memory thats already stored on the FileShare.
   1.148 + *       Prevent this by maintaining a per-hash algorithm map of FileShares */
   1.149 +static void add_hash (FileShare *file)
   1.150 +{
   1.151 +	Hash       *hash;
   1.152 +	ds_data_t   key;
   1.153 +	ds_data_t   value;
   1.154 +
   1.155 +	if (!(hash = share_get_hash (file, "SHA1")))
   1.156 +		return;
   1.157 +
   1.158 +	/* This shares the hash memory with the FileShare and also
   1.159 +	 * points directly at it. */
   1.160 +	ds_data_init (&key, hash->data, hash->len, DS_NOCOPY);
   1.161 +	ds_data_init (&value, file, 0, DS_NOCOPY);
   1.162 +
   1.163 +	/* We share the key with the FileShare, so remove the old key first
   1.164 +	 * so we don't end up sharing an old FileShare's hash. */
   1.165 +	dataset_remove_ex (sha1_hashes, &key);
   1.166 +	dataset_insert_ex (&sha1_hashes, &key, &value);
   1.167 +}
   1.168 +
   1.169 +static void remove_hash (FileShare *file)
   1.170 +{
   1.171 +	Hash       *hash;
   1.172 +
   1.173 +	if (!(hash = share_get_hash (file, "SHA1")))
   1.174 +		return;
   1.175 +
   1.176 +	/*
   1.177 +	 * If a FileShare is already present at this hash, and it isn't
   1.178 +	 * this FileShare, then don't remove it. This _will_ happen
   1.179 +	 * due to the way FileShares get added and removed on resyncs.
   1.180 +	 */
   1.181 +	if (dataset_lookup (sha1_hashes, hash->data, hash->len) != file)
   1.182 +		return;
   1.183 +
   1.184 +	dataset_remove (sha1_hashes, hash->data, hash->len);
   1.185 +
   1.186 +	if (dataset_length (sha1_hashes) == 0)
   1.187 +	{
   1.188 +		dataset_clear (sha1_hashes);
   1.189 +		sha1_hashes = NULL;
   1.190 +	}
   1.191 +}
   1.192 +
   1.193 +/******************************************************************************/
   1.194 +
   1.195 +static GtShare *gt_share_local_add (FileShare *file)
   1.196 +{
   1.197 +	GtShare *share;
   1.198 +	uint32_t index;
   1.199 +
   1.200 +	if (share_get_udata (file, GT->name))
   1.201 +		return NULL;
   1.202 +
   1.203 +	index = get_share_index (file);
   1.204 +
   1.205 +	if (!(share = gt_share_new_data (file, index)))
   1.206 +		return NULL;
   1.207 +
   1.208 +	add_hash (file);
   1.209 +	add_index (file, share);
   1.210 +
   1.211 +	return share;
   1.212 +}
   1.213 +
   1.214 +static void gt_share_local_remove (FileShare *file, GtShare *share)
   1.215 +{
   1.216 +	remove_index (file, share);
   1.217 +	remove_hash (file);
   1.218 +
   1.219 +	gt_share_free_data (file, share);
   1.220 +}
   1.221 +
   1.222 +static int find_by_index (ds_data_t *key, ds_data_t *value, void **args)
   1.223 +{
   1.224 +	uint32_t    *index    = args[0];
   1.225 +	char        *filename = args[1];
   1.226 +	FileShare  **ret      = args[2];
   1.227 +	FileShare   *file     = value->data;
   1.228 +	GtShare     *share;
   1.229 +
   1.230 +	if (!file || !(share = share_get_udata (file, GT->name)))
   1.231 +		return DS_CONTINUE;
   1.232 +
   1.233 +	if (share->index == *index &&
   1.234 +	    (!filename || !strcmp (filename, share->filename)))
   1.235 +	{
   1.236 +		*ret = file;
   1.237 +		return DS_BREAK;
   1.238 +	}
   1.239 +
   1.240 +	return DS_CONTINUE;
   1.241 +}
   1.242 +
   1.243 +FileShare *gt_share_local_lookup_by_index (uint32_t index, char *filename)
   1.244 +{
   1.245 +	FileShare *ret    = NULL;
   1.246 +	void      *args[] = { &index, filename, &ret };
   1.247 +
   1.248 +	share_foreach (DS_FOREACH_EX(find_by_index), args);
   1.249 +
   1.250 +	return ret;
   1.251 +}
   1.252 +
   1.253 +static FileShare *lookup_sha1 (char *urn)
   1.254 +{
   1.255 +	char           *str, *str0;
   1.256 +	char           *prefix;
   1.257 +	unsigned char  *bin;
   1.258 +	FileShare      *file;
   1.259 +
   1.260 +	if (!(str0 = str = STRDUP (urn)))
   1.261 +		return NULL;
   1.262 +
   1.263 +	/* TODO: consolidate with gt_protocol.c:parse_extended_data */
   1.264 +	string_upper (str0);
   1.265 +	string_sep (&str, "URN:");
   1.266 +
   1.267 +	prefix = string_sep (&str, ":");
   1.268 +
   1.269 +	/* Only support urn:sha1 or urn:sha-1 urns now */
   1.270 +	if (STRCMP (prefix, "SHA1") != 0 && STRCMP (prefix, "SHA-1") != 0)
   1.271 +	{
   1.272 +		free (str0);
   1.273 +		return NULL;
   1.274 +	}
   1.275 +
   1.276 +	string_trim (str);
   1.277 +
   1.278 +	if (strlen (str) != 32)
   1.279 +	{
   1.280 +		free (str0);
   1.281 +		return NULL;
   1.282 +	}
   1.283 +
   1.284 +	if (!(bin = sha1_bin (str)))
   1.285 +	{
   1.286 +		free (str0);
   1.287 +		return NULL;
   1.288 +	}
   1.289 +
   1.290 +	file = dataset_lookup (sha1_hashes, bin, SHA1_BINSIZE);
   1.291 +
   1.292 +	free (str0);
   1.293 +	free (bin);
   1.294 +
   1.295 +	return file;
   1.296 +}
   1.297 +
   1.298 +FileShare *gt_share_local_lookup_by_urn (char *urn)
   1.299 +{
   1.300 +	return lookup_sha1 (urn);
   1.301 +}
   1.302 +
   1.303 +static char *get_sha1 (FileShare *file)
   1.304 +{
   1.305 +	Hash *hash;
   1.306 +	char *urn;
   1.307 +	char *str;
   1.308 +
   1.309 +	if (!(hash = share_get_hash (file, "SHA1")))
   1.310 +		return NULL;
   1.311 +
   1.312 +	assert (hash->len == SHA1_BINSIZE);
   1.313 +
   1.314 +	if (!(str = sha1_string (hash->data)))
   1.315 +		return NULL;
   1.316 +
   1.317 +	urn = stringf_dup ("urn:sha1:%s", str);
   1.318 +	free (str);
   1.319 +
   1.320 +	return urn;
   1.321 +}
   1.322 +
   1.323 +char *gt_share_local_get_urns (FileShare *file)
   1.324 +{
   1.325 +	char *urn;
   1.326 +
   1.327 +	urn = get_sha1 (file);
   1.328 +
   1.329 +	return urn;
   1.330 +}
   1.331 +
   1.332 +int gt_share_local_sync_is_done (void)
   1.333 +{
   1.334 +	return sync_done;
   1.335 +}
   1.336 +
   1.337 +/******************************************************************************/
   1.338 +
   1.339 +void *gnutella_share_new (Protocol *p, FileShare *file)
   1.340 +{
   1.341 +	/* add this share to the data structures for searching */
   1.342 +	gt_search_exec_add (file);
   1.343 +
   1.344 +	return gt_share_local_add (file);
   1.345 +}
   1.346 +
   1.347 +void gnutella_share_free (Protocol *p, FileShare *file, void *data)
   1.348 +{
   1.349 +	/* remove data structures for searching */
   1.350 +	gt_search_exec_remove (file);
   1.351 +
   1.352 +	gt_share_local_remove (file, data);
   1.353 +}
   1.354 +
   1.355 +int gnutella_share_add (Protocol *p, FileShare *file, void *data)
   1.356 +{
   1.357 +	/* add to query routing tables */
   1.358 +	gt_query_router_self_add (file);
   1.359 +
   1.360 +	return TRUE;
   1.361 +}
   1.362 +
   1.363 +int gnutella_share_remove (Protocol *p, FileShare *file, void *data)
   1.364 +{
   1.365 +	/* remove from query routing tables */
   1.366 +	gt_query_router_self_remove (file);
   1.367 +
   1.368 +	return TRUE;
   1.369 +}
   1.370 +
   1.371 +void gnutella_share_sync (Protocol *p, int begin)
   1.372 +{
   1.373 +	gt_query_router_self_sync (begin);
   1.374 +
   1.375 +	if (begin)
   1.376 +	{
   1.377 +		sync_begun = TRUE;
   1.378 +	}
   1.379 +	else if (sync_begun)
   1.380 +	{
   1.381 +		sync_begun = FALSE;
   1.382 +		sync_done = TRUE;
   1.383 +
   1.384 +		/* synchronize the search structures (possibly, to disk) */
   1.385 +		gt_search_exec_sync ();
   1.386 +	}
   1.387 +}