pidgin/pidgin

facebook: Store sent message id in lastmid, to deduplicate echoed messages

2016-10-22, dequis
6d85d309f8e4
facebook: Store sent message id in lastmid, to deduplicate echoed messages

This is crappy and error prone, just like the rest of the duplicate
message handling code. It works, but it's going to get some echoes now
and then, particularly in quick moving groupchats.

I'm pretty sure this is a bug in the server, but the official clients
have much more elaborate deduplication built-in, so they won't notice.
/*
* purple
*
* Purple is the legal property of its developers, whose names are too numerous
* to list here. Please refer to the COPYRIGHT file distributed with this
* source distribution.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02111-1301 USA
*/
#include "internal.h"
#include "sha1hash.h"
/*******************************************************************************
* Structs
******************************************************************************/
#define PURPLE_SHA1_HASH_GET_PRIVATE(obj) \
(G_TYPE_INSTANCE_GET_PRIVATE((obj), PURPLE_TYPE_SHA1_HASH, PurpleSHA1HashPrivate))
typedef struct {
GChecksum *checksum;
} PurpleSHA1HashPrivate;
/******************************************************************************
* Globals
*****************************************************************************/
static GObjectClass *parent_class = NULL;
/******************************************************************************
* Hash Stuff
*****************************************************************************/
static void
purple_sha1_hash_reset(PurpleHash *hash)
{
PurpleSHA1Hash *sha1_hash = PURPLE_SHA1_HASH(hash);
PurpleSHA1HashPrivate *priv = PURPLE_SHA1_HASH_GET_PRIVATE(sha1_hash);
g_return_if_fail(priv != NULL);
g_return_if_fail(priv->checksum != NULL);
g_checksum_reset(priv->checksum);
}
static void
purple_sha1_hash_append(PurpleHash *hash, const guchar *data,
gsize len)
{
PurpleSHA1Hash *sha1_hash = PURPLE_SHA1_HASH(hash);
PurpleSHA1HashPrivate *priv = PURPLE_SHA1_HASH_GET_PRIVATE(sha1_hash);
g_return_if_fail(priv != NULL);
g_return_if_fail(priv->checksum != NULL);
while (len >= G_MAXSSIZE) {
g_checksum_update(priv->checksum, data, G_MAXSSIZE);
len -= G_MAXSSIZE;
data += G_MAXSSIZE;
}
if (len)
g_checksum_update(priv->checksum, data, len);
}
static gboolean
purple_sha1_hash_digest(PurpleHash *hash, guchar *digest, size_t buff_len)
{
PurpleSHA1Hash *sha1_hash = PURPLE_SHA1_HASH(hash);
PurpleSHA1HashPrivate *priv = PURPLE_SHA1_HASH_GET_PRIVATE(sha1_hash);
const gssize required_len = g_checksum_type_get_length(G_CHECKSUM_SHA1);
gsize digest_len = buff_len;
g_return_val_if_fail(priv != NULL, FALSE);
g_return_val_if_fail(priv->checksum != NULL, FALSE);
g_return_val_if_fail(required_len >= 0, FALSE);
g_return_val_if_fail(buff_len >= (gsize)required_len, FALSE);
g_checksum_get_digest(priv->checksum, digest, &digest_len);
if (digest_len != (gsize)required_len)
return FALSE;
purple_sha1_hash_reset(hash);
return TRUE;
}
static size_t
purple_sha1_hash_get_block_size(PurpleHash *hash)
{
return 64;
}
static size_t
purple_sha1_hash_get_digest_size(PurpleHash *hash)
{
return g_checksum_type_get_length(G_CHECKSUM_SHA1);
}
/******************************************************************************
* Object Stuff
*****************************************************************************/
static void
purple_sha1_hash_finalize(GObject *obj)
{
PurpleSHA1Hash *sha1_hash = PURPLE_SHA1_HASH(obj);
PurpleSHA1HashPrivate *priv = PURPLE_SHA1_HASH_GET_PRIVATE(sha1_hash);
if (priv->checksum)
g_checksum_free(priv->checksum);
parent_class->finalize(obj);
}
static void
purple_sha1_hash_class_init(PurpleSHA1HashClass *klass) {
GObjectClass *obj_class = G_OBJECT_CLASS(klass);
PurpleHashClass *hash_class = PURPLE_HASH_CLASS(klass);
parent_class = g_type_class_peek_parent(klass);
obj_class->finalize = purple_sha1_hash_finalize;
hash_class->reset = purple_sha1_hash_reset;
hash_class->reset_state = purple_sha1_hash_reset;
hash_class->append = purple_sha1_hash_append;
hash_class->digest = purple_sha1_hash_digest;
hash_class->get_digest_size = purple_sha1_hash_get_digest_size;
hash_class->get_block_size = purple_sha1_hash_get_block_size;
g_type_class_add_private(klass, sizeof(PurpleSHA1HashPrivate));
}
static void
purple_sha1_hash_init(PurpleHash *hash)
{
PurpleSHA1Hash *sha1_hash = PURPLE_SHA1_HASH(hash);
PurpleSHA1HashPrivate *priv = PURPLE_SHA1_HASH_GET_PRIVATE(sha1_hash);
priv->checksum = g_checksum_new(G_CHECKSUM_SHA1);
purple_sha1_hash_reset(hash);
}
/******************************************************************************
* API
*****************************************************************************/
GType
purple_sha1_hash_get_type(void) {
static GType type = 0;
if(type == 0) {
static const GTypeInfo info = {
sizeof(PurpleSHA1HashClass),
NULL,
NULL,
(GClassInitFunc)purple_sha1_hash_class_init,
NULL,
NULL,
sizeof(PurpleSHA1Hash),
0,
(GInstanceInitFunc)purple_sha1_hash_init,
NULL,
};
type = g_type_register_static(PURPLE_TYPE_HASH,
"PurpleSHA1Hash",
&info, 0);
}
return type;
}
PurpleHash *
purple_sha1_hash_new(void) {
return g_object_new(PURPLE_TYPE_SHA1_HASH, NULL);
}