Return-Path: Message-ID: Date: Tue, 3 Apr 2007 11:40:58 +0100 From: "Meenakshi Seeballack" To: bluez-devel@lists.sourceforge.net MIME-Version: 1.0 Subject: [Bluez-devel] L2CAP sockets, SDP Reply-To: BlueZ development List-Id: BlueZ development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: multipart/mixed; boundary="===============1508818638==" Sender: bluez-devel-bounces@lists.sourceforge.net Errors-To: bluez-devel-bounces@lists.sourceforge.net --===============1508818638== Content-Type: multipart/alternative; boundary="----=_Part_4575_25091685.1175596858485" ------=_Part_4575_25091685.1175596858485 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline Hello, I have tried to understand how to open an L2CAP socket, and have used the BlueZ API. This is what I have got so far: /* * l2cap_listen(l2cap_channel) * Use this channel as a listening post */ static int l2cap_listen(const bdaddr_t *bdaddr, unsigned short psm, int lm, int backlog) { struct sockaddr_l2 addr; struct l2cap_options opts; int sk; /* allocate a free socket */ if ((sk = socket(PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_L2CAP)) < 0) return -1; /* open connection to remote device */ memset(&addr, 0, sizeof(addr)); addr.l2_family = AF_BLUETOOTH; bacpy(&addr.l2_bdaddr, bdaddr); /* update source address of socket */ addr.l2_psm = htobs(psm); /* bind socket to newly formed socket */ if (bind(sk, (struct sockaddr *) &addr, sizeof(addr)) < 0) { perror("ERROR: Could not bind socket"); close(sk); return -1; } setsockopt(sk, SOL_L2CAP, L2CAP_LM, &lm, sizeof(lm)); memset(&opts, 0, sizeof(opts)); opts.imtu = HIDP_DEFAULT_MTU; opts.omtu = HIDP_DEFAULT_MTU; opts.flush_to = 0xffff; setsockopt(sk, SOL_L2CAP, L2CAP_OPTIONS, &opts, sizeof(opts)); /* backlog: specifies the number of unaccepted connection * that the system will allow before refusing new connections */ if (listen(sk, backlog) < 0) { close(sk); return -1; } return sk; } /* * l2cap_connect_req() * Establishes connection with specific socket * Request to establish connection from remote * communication partner. * Such a socket has to have been previously created * by an application with the command listen. */ static int l2cap_connect(bdaddr_t *src, bdaddr_t *dst, unsigned short psm) { struct sockaddr_l2 addr; struct l2cap_options opts; int sk; /* socket allocation */ if ((sk = socket(PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_L2CAP)) < 0) perror("ERROR: Could not create socket"); return -1; memset(&addr, 0, sizeof(addr)); addr.l2_family = AF_BLUETOOTH; bacpy(&addr.l2_bdaddr, src); /*update source address of socket */ /* binds socket to psm */ if (bind(sk, (struct sockaddr *) &addr, sizeof(addr)) < 0) { close(sk); return -1; } memset(&opts, 0, sizeof(opts)); opts.imtu = HIDP_DEFAULT_MTU; opts.omtu = HIDP_DEFAULT_MTU; opts.flush_to = 0xffff; setsockopt(sk, SOL_L2CAP, L2CAP_OPTIONS, &opts, sizeof(opts)); memset(&addr, 0, sizeof(addr)); addr.l2_family = AF_BLUETOOTH; bacpy(&addr.l2_bdaddr, dst); addr.l2_psm = htobs(psm); if (connect(sk, (struct sockaddr *) &addr, sizeof(addr)) < 0) { close(sk); return -1; } return sk; } /* * l2cap_accept() * (Permits incoming connection) * Blocks and accepts incoming connection * Function switches from BT_LISTEN to BT_CONNECTED */ static int l2cap_accept(int sk, bdaddr_t *bdaddr) { struct sockaddr_l2 addr; socklen_t addrlen; int nsk; memset(&addr, 0, sizeof(addr)); addrlen = sizeof(addr); // accept one connection if ((nsk = accept(sk, (struct sockaddr *) &addr, &addrlen)) < 0) return -1; if (bdaddr) bacpy(bdaddr, &addr.l2_bdaddr); return nsk; } -------------------- I am eventually aiming to register the mouse HID events, and send it via the L2CAP socket to "control" another bluetooth-enabled PC. How do I use an SDP service in conjunction with the existing L2CAP code? How do I use the control channel (L2CAP_PSM_HIDP_CTRL 0x11) and the interrupt channel (L2CAP_PSM_HIDP_INTR 0x13) I think the control channel is used by SDP for signalling, (device discovery); the interrupt channel is used for data transfer (service discovery) Thanks in advance for any help! ------=_Part_4575_25091685.1175596858485 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline Hello,
I have tried to understand how to open an L2CAP socket, and have used the BlueZ API. This is what I have got so far:
/*
 * l2cap_listen(l2cap_channel)
 * Use this channel as a listening post
 */
static int l2cap_listen(const bdaddr_t *bdaddr, unsigned short psm, int lm, int backlog)
{
    struct sockaddr_l2 addr;
    struct l2cap_options opts;
    int sk;
   
    /* allocate a free socket */
    if ((sk = socket(PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_L2CAP)) < 0)
        return -1;

    /* open connection to remote device */
    memset(&addr, 0, sizeof(addr));
    addr.l2_family = AF_BLUETOOTH;
    bacpy(&addr.l2_bdaddr, bdaddr); /* update source address of socket */
    addr.l2_psm = htobs(psm);
   
    /* bind socket to newly formed socket */
    if (bind(sk, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
        perror("ERROR: Could not bind socket");
        close(sk);
        return -1;
    }

    setsockopt(sk, SOL_L2CAP, L2CAP_LM, &lm, sizeof(lm));

    memset(&opts, 0, sizeof(opts));
    opts.imtu = HIDP_DEFAULT_MTU;
    opts.omtu = HIDP_DEFAULT_MTU;
    opts.flush_to = 0xffff;
   
    setsockopt(sk, SOL_L2CAP, L2CAP_OPTIONS, &opts, sizeof(opts));
   
    /* backlog: specifies the number of unaccepted connection
     * that the system will allow before refusing new connections
     */
    if (listen(sk, backlog) < 0) {
        close(sk);
        return -1;
    }

    return sk;
}

/*
 * l2cap_connect_req()
 * Establishes connection with specific socket
 * Request to establish connection from remote
 * communication partner.
 * Such a socket has to have been previously created
 * by an application with the command listen.
 */
static int l2cap_connect(bdaddr_t *src, bdaddr_t *dst, unsigned short psm)
{
    struct sockaddr_l2 addr;
    struct l2cap_options opts;
    int sk;

    /* socket allocation */
    if ((sk = socket(PF_BLUETOOTH, SOCK_SEQPACKET, BTPROTO_L2CAP)) < 0)
        perror("ERROR: Could not create socket");
        return -1;

    memset(&addr, 0, sizeof(addr));
    addr.l2_family  = AF_BLUETOOTH;
    bacpy(&addr.l2_bdaddr, src); /*update source address of socket */
   
    /* binds socket to psm */
    if (bind(sk, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
        close(sk);
        return -1;
    }

    memset(&opts, 0, sizeof(opts));
    opts.imtu = HIDP_DEFAULT_MTU;
    opts.omtu = HIDP_DEFAULT_MTU;
    opts.flush_to = 0xffff;

    setsockopt(sk, SOL_L2CAP, L2CAP_OPTIONS, &opts, sizeof(opts));

    memset(&addr, 0, sizeof(addr));
    addr.l2_family  = AF_BLUETOOTH;
    bacpy(&addr.l2_bdaddr, dst);
    addr.l2_psm = htobs(psm);

    if (connect(sk, (struct sockaddr *) &addr, sizeof(addr)) < 0) {
        close(sk);
        return -1;
    }

    return sk;
}

/*
 * l2cap_accept()
 * (Permits incoming connection)
 * Blocks and accepts incoming connection
 * Function switches from BT_LISTEN to BT_CONNECTED
 */
static int l2cap_accept(int sk, bdaddr_t *bdaddr)
{
    struct sockaddr_l2 addr;
    socklen_t addrlen;
    int nsk;

    memset(&addr, 0, sizeof(addr));
    addrlen = sizeof(addr);

    // accept one connection
    if ((nsk = accept(sk, (struct sockaddr *) &addr, &addrlen)) < 0)
        return -1;

    if (bdaddr)
        bacpy(bdaddr, &addr.l2_bdaddr);

    return nsk;
}
--------------------
I am eventually aiming to register the mouse HID events, and send it via the L2CAP socket to "control" another bluetooth-enabled PC.
How do I use an SDP service in conjunction with the existing L2CAP code? How do I use the control channel (L2CAP_PSM_HIDP_CTRL 0x11) and the interrupt channel (L2CAP_PSM_HIDP_INTR 0x13)
I think the control channel is used by SDP for signalling, (device discovery); the interrupt channel is used for data transfer (service discovery)
Thanks in advance for any help!

------=_Part_4575_25091685.1175596858485-- --===============1508818638== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline ------------------------------------------------------------------------- Take Surveys. Earn Cash. Influence the Future of IT Join SourceForge.net's Techsay panel and you'll get the chance to share your opinions on IT & business topics through brief surveys-and earn cash http://www.techsay.com/default.php?page=join.php&p=sourceforge&CID=DEVDEV --===============1508818638== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Bluez-devel mailing list Bluez-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bluez-devel --===============1508818638==--