odc.c

Linux下的多协议即时通讯程序源代码

				break;
			}
			size = atol(sizestr);

			g_datalist_clear(&attributes);

			if ((size > 0) && (tmp + size > dataend))
				break;

			embedded_data = g_new(struct embedded_data, 1);
			embedded_data->size = size;
			embedded_data->data = (const guint8 *)tmp;
			tmp += size;

			/* Skip past the closing </data> tag */
			if (strncasecmp(tmp, "</data>", 7))
			{
				g_free(embedded_data);
				break;
			}
			tmp += 7;

			g_hash_table_insert(embedded_datas,
					GINT_TO_POINTER(id), embedded_data);
		}
	}

	/*
	 * Loop through the message, replacing OSCAR img tags with the
	 * equivalent Purple img tag.
	 */
	images = NULL;
	newmsg = g_string_new("");
	tmp = msg;
	while (purple_markup_find_tag("img", tmp, &start, &end, &attributes))
	{
		int imgid = 0;

		idstr   = g_datalist_get_data(&attributes, "id");
		src     = g_datalist_get_data(&attributes, "src");
		sizestr = g_datalist_get_data(&attributes, "datasize");

		if ((idstr != NULL) && (src != NULL) && (sizestr!= NULL))
		{
			unsigned int id;
			size_t size;

			id = atoi(idstr);
			size = atol(sizestr);
			embedded_data = g_hash_table_lookup(embedded_datas,
					GINT_TO_POINTER(id));

			if ((embedded_data != NULL) && (embedded_data->size == size))
			{
				imgid = purple_imgstore_add_with_id(g_memdup(embedded_data->data, size), size, src);

				/* Record the image number */
				images = g_slist_append(images, GINT_TO_POINTER(imgid));
			}
		}

		/* Delete the attribute list */
		g_datalist_clear(&attributes);

		/* Append the message up to the tag */
		utf8 = purple_plugin_oscar_decode_im_part(account, conn->sn,
				encoding, 0x0000, tmp, start - tmp);
		if (utf8 != NULL) {
			g_string_append(newmsg, utf8);
			g_free(utf8);
		}

		if (imgid != 0)
		{
			/* Write the new image tag */
			g_string_append_printf(newmsg, "<IMG ID=\"%d\">", imgid);
		}

		/* Continue from the end of the tag */
		tmp = end + 1;
	}

	/* Append any remaining message data */
	if (tmp <= msgend)
	{
		utf8 = purple_plugin_oscar_decode_im_part(account, conn->sn,
				encoding, 0x0000, tmp, msgend - tmp);
		if (utf8 != NULL) {
			g_string_append(newmsg, utf8);
			g_free(utf8);
		}
	}

	/* Send the message */
	imflags = 0;
	if (images != NULL)
		imflags |= PURPLE_MESSAGE_IMAGES;
	if (autoreply)
		imflags |= PURPLE_MESSAGE_AUTO_RESP;
	serv_got_im(gc, conn->sn, newmsg->str, imflags, time(NULL));
	g_string_free(newmsg, TRUE);

	/* unref any images we allocated */
	if (images)
	{
		GSList *l;
		for (l = images; l != NULL; l = l->next)
			purple_imgstore_unref_by_id(GPOINTER_TO_INT(l->data));
		g_slist_free(images);
	}

	/* Delete our list of pointers to embedded images */
	g_hash_table_destroy(embedded_datas);
}

/**
 * This is a purple_input_add() watcher callback function for reading
 * direct IM payload data.  "Payload data" is always an IM and
 * maybe some embedded images or files or something.  The actual
 * ODC frame is read using peer_connection_recv_cb().  We temporarily
 * switch to this watcher callback ONLY to read the payload, and we
 * switch back once we're done.
 */
static void
peer_odc_recv_cb(gpointer data, gint source, PurpleInputCondition cond)
{
	PeerConnection *conn;
	OdcFrame *frame;
	ByteStream *bs;
	ssize_t read;

	conn = data;
	frame = conn->frame;
	bs = &frame->payload;

	/* Read data into the temporary buffer until it is complete */
	read = recv(conn->fd,
				&bs->data[bs->offset],
				bs->len - bs->offset,
				0);

	/* Check if the remote user closed the connection */
	if (read == 0)
	{
		peer_connection_destroy(conn, OSCAR_DISCONNECT_REMOTE_CLOSED, NULL);
		return;
	}

	if (read < 0)
	{
		if ((errno == EAGAIN) || (errno == EWOULDBLOCK))
			/* No worries */
			return;

		peer_connection_destroy(conn,
				OSCAR_DISCONNECT_LOST_CONNECTION, strerror(errno));
		return;
	}

	bs->offset += read;
	if (bs->offset < bs->len)
		/* Waiting for more data to arrive */
		return;

	/* We have a complete ODC/OFT frame!  Handle it and continue reading */
	byte_stream_rewind(bs);
	peer_odc_handle_payload(conn, (const char *)bs->data,
			bs->len, frame->encoding, frame->flags & 0x0001);
	g_free(bs->data);
	bs->data = NULL;
	g_free(frame);
	conn->frame = NULL;

	purple_input_remove(conn->watcher_incoming);
	conn->watcher_incoming = purple_input_add(conn->fd,
			PURPLE_INPUT_READ, peer_connection_recv_cb, conn);
}

/**
 * Handle an incoming OdcFrame.  If there is a payload associated
 * with this frame, then we remove the old watcher and add the
 * ODC watcher to read in the payload.
 */
void
peer_odc_recv_frame(PeerConnection *conn, ByteStream *bs)
{
	PurpleConnection *gc;
	OdcFrame *frame;

	gc = conn->od->gc;

	frame = g_new0(OdcFrame, 1);
	frame->type = byte_stream_get16(bs);
	frame->subtype = byte_stream_get16(bs);
	byte_stream_advance(bs, 2);
	byte_stream_getrawbuf(bs, frame->cookie, 8);
	byte_stream_advance(bs, 8);
	frame->payload.len = byte_stream_get32(bs);
	frame->encoding = byte_stream_get16(bs);
	byte_stream_advance(bs, 4);
	frame->flags = byte_stream_get16(bs);
	byte_stream_advance(bs, 4);
	byte_stream_getrawbuf(bs, frame->sn, 32);

	purple_debug_info("oscar", "Incoming ODC frame from %s with "
			"type=0x%04x, flags=0x%04x, payload length=%u\n",
			frame->sn, frame->type, frame->flags, frame->payload.len);

	if (!conn->ready)
	{
		/*
		 * We need to verify the cookie so that we know we are
		 * connected to our friend and not a malicious middle man.
		 */

		PurpleAccount *account;
		PurpleConversation *conv;

		if (conn->flags & PEER_CONNECTION_FLAG_IS_INCOMING)
		{
			if (memcmp(conn->cookie, frame->cookie, 8))
			{
				/*
				 * Oh no!  The user that connected to us did not send
				 * the correct cookie!  They are not our friend.  Go try
				 * to accept another connection?
				 */
				purple_debug_info("oscar", "Received an incorrect cookie.  "
					"Closing connection.\n");
				peer_connection_destroy(conn,
						OSCAR_DISCONNECT_INVALID_DATA, NULL);
				g_free(frame);
				return;
			}

			/*
			 * Ok, we know they are legit.  Now be courteous and
			 * send them our cookie.  Note: This doesn't seem
			 * to be necessary, but it also doesn't seem to hurt.
			 */
			peer_odc_send_cookie(conn);
		}

		conn->ready = TRUE;

		/*
		 * If they connected to us then close the listener socket
		 * and send them our cookie.
		 */
		if (conn->listenerfd != -1)
		{
			close(conn->listenerfd);
			conn->listenerfd = -1;
		}

		/* Tell the local user that we are connected */
		account = purple_connection_get_account(gc);
		conv = purple_conversation_new(PURPLE_CONV_TYPE_IM, account, conn->sn);
		purple_conversation_write(conv, NULL, _("Direct IM established"),
				PURPLE_MESSAGE_SYSTEM, time(NULL));
	}

	if ((frame->type != 0x0001) && (frame->subtype != 0x0006))
	{
		purple_debug_info("oscar", "Unknown ODC frame type 0x%04hx, "
				"subtype 0x%04hx.\n", frame->type, frame->subtype);
		return;
	}

	if (frame->flags & 0x0008)
	{
		/* I had to leave this. It's just too funny. It reminds me of my sister. */
		purple_debug_info("oscar", "ohmigod! %s has started typing "
			"(DirectIM). He's going to send you a message! "
			"*squeal*\n", conn->sn);
		serv_got_typing(gc, conn->sn, 0, PURPLE_TYPING);
	}
	else if (frame->flags & 0x0004)
	{
		serv_got_typing(gc, conn->sn, 0, PURPLE_TYPED);
	}
	else
	{
		serv_got_typing_stopped(gc, conn->sn);
	}

	if (frame->payload.len > 0)
	{
		/* We have payload data!  Switch to the ODC watcher to read it. */
		frame->payload.data = g_new(guint8, frame->payload.len);
		frame->payload.offset = 0;
		conn->frame = frame;
		purple_input_remove(conn->watcher_incoming);
		conn->watcher_incoming = purple_input_add(conn->fd,
				PURPLE_INPUT_READ, peer_odc_recv_cb, conn);
		return;
	}

	g_free(frame);
}