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I made Ping Program using C++, icmp. But it doesnt work on android

This is ping code. After select function, retval is just 0. I checked this is working good on mac os. and I checked a lot of ip. but it doesn't work only android device. I don't know what is problem. i made socket using SOCK_RAW at first time, but it works properly for superuser only. so i changed it SOCK_DGRAM. and it worked on mac os for normal user. Is it related to it?
int ping(string target)
{
int s, i, cc, packlen, datalen = DEFDATALEN;
struct hostent *hp;
struct sockaddr_in to, from;
struct ip *ip;
u_char *packet, outpack[MAXPACKET];
char hnamebuf[MAXHOSTNAMELEN];
string hostname;
struct icmp *icp;
int ret, fromlen, hlen;
fd_set rfds;
struct timeval tv;
int retval;
struct timeval start, end;
int end_t;
bool cont = true;
to.sin_family = AF_INET;
to.sin_addr.s_addr = htonl(inet_addr(target.c_str()));
//to.sin_port = 0;
if (to.sin_addr.s_addr != (u_int)-1)
{
hostname = target;
pErrorLabel->setString(hostname);
}
else
{
hp = gethostbyname(target.c_str());
if (!hp)
{
pErrorLabel->setString("Unknown host");
cerr << "unknown host " << target << endl;
return -1;
}
to.sin_family = hp->h_addrtype;
bcopy(hp->h_addr, (caddr_t)&to.sin_addr, hp->h_length);
strncpy(hnamebuf, hp->h_name, sizeof(hnamebuf) - 1);
hostname = hnamebuf;
}
packlen = datalen + MAXIPLEN + MAXICMPLEN;
if ((packet = (u_char *)malloc((u_int)packlen)) == NULL)
{
pErrorLabel->setString("malloc error");
cerr << "malloc error\n";
return -1;
}
if ((s = socket(AF_INET, SOCK_DGRAM, IPPROTO_ICMP)) < 0)
{
pErrorLabel->setString("administrator");
return -1; /* Needs to run as superuser!! */
}
icp = (struct icmp *)outpack;
icp->icmp_type = ICMP_ECHO;
icp->icmp_code = 0;
icp->icmp_cksum = 0;
icp->icmp_seq = 12345;
icp->icmp_id = getpid();
cc = datalen + ICMP_MINLEN;
icp->icmp_cksum = in_cksum((unsigned short *)icp, cc);
gettimeofday(&start, NULL);
i = sendto(s, (char *)outpack, cc, 0, (struct sockaddr*)&to, (socklen_t)sizeof(struct sockaddr_in));
if (i < 0 || i != cc)
{
if (i < 0)
perror("sendto error");
cout << "wrote " << hostname << " " << cc << " chars, ret= " << i << endl;
}
FD_ZERO(&rfds);
FD_SET(s, &rfds);
tv.tv_sec = 5;
tv.tv_usec = 0;
std::stringstream ss;
ss << "socket=" << (int)s;
pErrorLabel->setString(ss.str().c_str());
while (cont)
{
retval = select(s + 1, &rfds, NULL, NULL, &tv);
if (retval == -1)
{
perror("select()");
pErrorLabel->setString("select()");
return -1;
}
else if (retval)
{
fromlen = sizeof(sockaddr_in);
if ((ret = recvfrom(s, (char *)packet, packlen, 0, (struct sockaddr *)&from, (socklen_t*)&fromlen)) < 0)
{
perror("recvfrom error");
pErrorLabel->setString("recvfrom error");
return -1;
}
// Check the IP header
ip = (struct ip *)((char*)packet);
hlen = sizeof(struct ip);
if (ret < (hlen + ICMP_MINLEN))
{
cerr << "packet too short (" << ret << " bytes) from " << hostname << endl;;
return -1;
}
// Now the ICMP part
icp = (struct icmp *)(packet + hlen);
if (icp->icmp_type == ICMP_ECHOREPLY)
{
if (icp->icmp_seq != 12345)
{
cout << "received sequence # " << icp->icmp_seq << endl;
continue;
}
if (icp->icmp_id != getpid())
{
cout << "received id " << icp->icmp_id << endl;
continue;
}
cont = false;
}
else
{
continue;
}
gettimeofday(&end, NULL);
end_t = 1000000 * (end.tv_sec - start.tv_sec) + (end.tv_usec - start.tv_usec);
if (end_t < 1)
end_t = 1;
cout << "Elapsed time = " << end_t << " usec" << endl;
return end_t;
}
else
{
cout << "No data within one seconds.\n";
return 0;
}
}
return 0;
}

Android TCP client receive messages and bmp

I use the common tcp client to receive string messages through TCP.
I want after the reception of a specific message e.g. "XXX" my client to be ready to receive a bmp image.
My server in C++ sends the messages but the client does not receive the image...
After some suggestions .. se below I udated the code...
Here is my code:
TCP client:
public class TCPClient {
private String serverMessage;
public static final String SERVERIP = "192.168.1.88"; //your computer IP
public static final int SERVERPORT = 80;
private OnMessageReceived mMessageListener = null;
private boolean mRun = false;
private PrintWriter out;
private BufferedReader input;
private DataInputStream dis;
/**
* Constructor of the class. OnMessagedReceived listens for the messages received from server
*/
public TCPClient(OnMessageReceived listener) {
mMessageListener = listener;
}
/**
* Sends the message entered by client to the serveraddress
* #param message text entered by client
*/
public void sendMessage(String message){
if (out != null && !out.checkError()) {
out.println(message);
out.flush();
}
}
public void stopClient(){
mRun = false;
if (out != null) {
out.flush();
out.close();
}
mMessageListener = null;
input = null;
input = null;
input = null;
serverMessage = null;
}
public void run() {
mRun = true;
try {
//here you must put your computer's IP address.
InetAddress serverAddr = InetAddress.getByName(SERVERIP);
Log.e("TCP Client", "C: Connecting...");
//create a socket to make the connection with the server
Socket socket = new Socket(serverAddr, SERVERPORT);
try {
//send the message to the server
out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getOutputStream())), true);
Log.e("TCP Client", "C: Sent.");
Log.e("TCP Client", "C: Done.");
//receive the message which the server sends back
dis = new DataInputStream(socket.getInputStream());
// The buffer reader cannot can't wrap an InputStream directly. It wraps another Reader.
// So inputstreamreader is used.
input = new BufferedReader(new InputStreamReader(dis, "UTF-8"));
Log.d("MyApp","We are here");
//this.input = new DataInputStream(in);
//in this while the client listens for the messages sent by the server
while (mRun) {
Log.d("MyApp", "We are here 2");
serverMessage = input.readLine();
if (serverMessage != null && mMessageListener != null) {
//call the method messageReceived from MyActivity class
mMessageListener.messageReceived(serverMessage);
Log.d("RESPONSE FROM SERVER", "S: Received Message: '" + serverMessage + "'");
}
if ("XXX".equals(serverMessage)) {
Log.d("MyApp", "We are here 3");
serverMessage = null;
while (mRun) {
WriteSDCard writeSDCard = new WriteSDCard();
writeSDCard.writeToSDFile(serverMessage);
}
}
}
} finally {
socket.close();
}
Log.e("RESPONSE FROM SERVER", "S: Received Message: '" + serverMessage + "'");
} catch (Exception e) {
Log.e("TCP", "S: Error", e);
} finally {
//the socket must be closed. It is not possible to reconnect to this socket
// after it is closed, which means a new socket instance has to be created.
}
}
//Declare the interface. The method messageReceived(String message) will must be implemented in the MyActivity
//class at on asynckTask doInBackground
public interface OnMessageReceived {
public void messageReceived(String message);
}
}
public class WriteSDCard extends Activity {
private static final String TAG = "MEDIA";
private TextView tv;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//(not needed) setContentView(R.layout.main);
//(not needed) tv = (TextView) findViewById(R.id.TextView01);
checkExternalMedia();
String message =null;
}
/** Method to check whether external media available and writable. This is adapted from
http://developer.android.com/guide/topics/data/data-storage.html#filesExternal */
private void checkExternalMedia(){
boolean mExternalStorageAvailable = false;
boolean mExternalStorageWriteable = false;
String state = Environment.getExternalStorageState();
if (Environment.MEDIA_MOUNTED.equals(state)) {
// Can read and write the media
mExternalStorageAvailable = mExternalStorageWriteable = true;
} else if (Environment.MEDIA_MOUNTED_READ_ONLY.equals(state)) {
// Can only read the media
mExternalStorageAvailable = true;
mExternalStorageWriteable = false;
} else {
// Can't read or write
mExternalStorageAvailable = mExternalStorageWriteable = false;
}
tv.append("\n\nExternal Media: readable="
+mExternalStorageAvailable+" writable="+mExternalStorageWriteable);
}
/** Method to write ascii text characters to file on SD card. Note that you must add a
WRITE_EXTERNAL_STORAGE permission to the manifest file or this method will throw
a FileNotFound Exception because you won't have write permission. */
void writeToSDFile(String inputMsg){
// Find the root of the external storage.
// See http://developer.android.com/guide/topics/data/data- storage.html#filesExternal
File root = android.os.Environment.getExternalStorageDirectory();
tv.append("\nExternal file system root: "+root);
// See http://stackoverflow.com/questions/3551821/android-write-to-sd-card-folder
File dir = new File (root.getAbsolutePath() + "/download");
dir.mkdirs();
Log.d("WriteSDCard", "Start writing");
File file = new File(dir, "myData.txt");
try {
FileOutputStream f = new FileOutputStream(file);
PrintWriter pw = new PrintWriter(f);
pw.println(inputMsg);
pw.flush();
pw.close();
f.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
Log.i(TAG, "******* File not found. Did you" +
" add a WRITE_EXTERNAL_STORAGE permission to the manifest?");
} catch (IOException e) {
e.printStackTrace();
}
tv.append("\n\nFile written to "+file);
}
/** Method to read in a text file placed in the res/raw directory of the application. The
method reads in all lines of the file sequentially. */
}
And the server side:
Code:
void sendBMP( int cs, int xs, int ys)
{
int imgdataoffset = 14 + 40; // file header size + bitmap header size
int rowsz = ((xs) + 3) & -4; // size of one padded row of pixels
int imgdatasize = (((xs*3) + 3) & -4) * ys; // size of image data
int filesize = imgdataoffset + imgdatasize;
int i, y;
HTLM_bmp_H HTLM_bmp_h;
HTLM_bmp_h.bmfh.bfSize = filesize;
HTLM_bmp_h.bmfh.bfReserved1 = 0;
HTLM_bmp_h.bmfh.bfReserved2 = 0;
HTLM_bmp_h.bmfh.bfOffBits = imgdataoffset;
HTLM_bmp_h.bmih.biSize = 40;
HTLM_bmp_h.bmih.biWidth = xs;
HTLM_bmp_h.bmih.biHeight = ys;
HTLM_bmp_h.bmih.biPlanes = 1;
HTLM_bmp_h.bmih.biBitCount = 24;
HTLM_bmp_h.bmih.biCompression = 0;
HTLM_bmp_h.bmih.biSizeImage = imgdatasize;
HTLM_bmp_h.bmih.biXPelsPerMeter = 1000;
HTLM_bmp_h.bmih.biYPelsPerMeter = 1000;
HTLM_bmp_h.bmih.biClrUsed = 1 << 24;
HTLM_bmp_h.bmih.biClrImportant = 0;
printf("Start Sending BMP.\n");
send(cs,(unsigned char *)"BM",2,0);
send(cs,(unsigned char *)&HTLM_bmp_h,sizeof(HTLM_bmp_h),0);
printf("Sending...\n");
Buff_ptr = 0;
send(cs, (unsigned char *)Rbuffer, BUFF_SIZE,0 );
send(cs, (unsigned char *)Gbuffer, BUFF_SIZE,0 );
send(cs, (unsigned char *)Bbuffer, BUFF_SIZE,0 );
send(cs, (unsigned char *)"\n",1,0);
send(cs, (unsigned char *)"END\n",4,0);
printf("Done\n\n");
}
typedef struct {
// char bfType1;
// char bfType2;
int bfSize;
short bfReserved1;
short bfReserved2;
int bfOffBits;
} BMFH;
typedef struct {
unsigned int biSize;
int biWidth;
int biHeight;
short biPlanes;
short biBitCount;
unsigned int biCompression;
unsigned int biSizeImage;
int biXPelsPerMeter;
int biYPelsPerMeter;
unsigned int biClrUsed;
unsigned int biClrImportant;
} BMIH;
typedef struct {
BMFH bmfh;
BMIH bmih;
} HTLM_bmp_H;
main()
{
TSK_Handle tsk_cam;
tsk_cam=TSK_create( (Fxn)TSK_webview, NULL);
TSK_setpri(tsk_cam, 8);
}
char buffer[2048];
Void TSK_webview()
{
int s,cs;
struct sockaddr_in addr; /* generic socket name */
struct sockaddr client_addr;
int sock_len = sizeof(struct sockaddr);
int frame = 0;
LgUns i=0;
int len;
int x = DSKeye_SXGA_WIDTH, y = DSKeye_SXGA_HEIGHT;
DSKeye_params CAM_params = {
....
};
lwIP_NetStart();
/**************************************************************
* Main loop.
***************************************************************/
s = socket( AF_INET, SOCK_STREAM, 0 );
addr.sin_port = htons(80);
addr.sin_addr.s_addr = 0;
memset(&(addr.sin_zero), 0, sizeof(addr.sin_zero));
printf("start\n");
if( bind(s, (struct sockaddr*)&addr, sizeof(struct sockaddr)))
{
printf("error binding to port\n");
return ;
}
printf("xx1\n");
if(DSKeye_open(&CAM_params)) {
printf("xx2\n");
SYS_abort("DSKcam_CAMopen");
printf("xx3\n"); fflush(stdout);}
printf("xx4\n");
while(1==1) {
printf("Waiting for client to be connected ... \n");
listen(s, 10);
cs = accept(s, &client_addr, &sock_len);
printf("Client connected.\n");
send(cs,(unsigned char *)"Server connected\n",17,0);
recv(cs, (unsigned char*)buffer, 17, 0);
switch (*(buffer)){
case 'A' :
...
case 'B' :
...
}
REG32(0xA0000080)=REG32(0xA0000080) - 0x800000; ///Disable stepper controller vhdl Quartus Block
for(frame = 0; frame < 4; frame++){ // Allow AEC etc to settle
SrcFrame=DSKeye_getFrame();
}
printf("Demosaicing of %d x %d image is ongoing \n", x, y);
demosaic(SrcFrame, x, y);
break;
}
printf("Demosaicing completed ...\n");
send(cs,(unsigned char *)"Demosaicing completed\n",22,0);
send(cs,(unsigned char *)"XXX\n",4,0);
sendBMP(cs, x, y);
fflush(stdout);
lwip_close(cs);
}
the send : lwip_send
int lwip_send(int s, void *data, int size, unsigned int flags)
{
struct lwip_socket *sock;
struct netbuf *buf;
err_t err;
LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_send(%d, data=%p, size=%d, flags=0x%x)\n", s, data, size, flags));
sock = get_socket(s);
if (!sock) {
set_errno(EBADF);
return -1;
}
switch (netconn_type(sock->conn)) {
case NETCONN_RAW:
case NETCONN_UDP:
case NETCONN_UDPLITE:
case NETCONN_UDPNOCHKSUM:
/* create a buffer */
buf = netbuf_new();
if (!buf) {
LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_send(%d) ENOBUFS\n", s));
sock_set_errno(sock, ENOBUFS);
return -1;
}
/* make the buffer point to the data that should
be sent */
netbuf_ref(buf, data, size);
/* send the data */
err = netconn_send(sock->conn, buf);
/* deallocated the buffer */
netbuf_delete(buf);
break;
case NETCONN_TCP:
err = netconn_write(sock->conn, data, size, NETCONN_COPY);
break;
default:
err = ERR_ARG;
break;
}
if (err != ERR_OK) {
LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_send(%d) err=%d\n", s, err));
sock_set_errno(sock, err_to_errno(err));
return -1;
}
LWIP_DEBUGF(SOCKETS_DEBUG, ("lwip_send(%d) ok size=%d\n", s, size));
sock_set_errno(sock, 0);
return size;
}

You can't mix a buffered reader and a data input stream on the same socket. The buffered reader will read-ahead and steal data you expect to read via the data input stream. You will have to use the data input stream for everything. And correspondingly at the sender.

You're doing incorrect comparison for string equality.
In Java, string comparison for equality is done using String.equals(Object anObject)
You're using if (serverMessage == "XXX") {....
You should use if ("XXX".equals(serverMessage)) {....

Android USB host read from device

I'm trying to get some data out of a USB device connected to my Android phone that is on host mode. I'm able to send data to it, but reading fails.
I've looked at several examples and tried all I could but I don't have any experience in USB communication, although by now I know a little, and I've been stuck on this longer that I care to admit.
I'm not very familiar with the endpoint configuration, but I know is that my device uses a CDC type communication method and both the output (from phone to device) and input are registered.
Here's the whole class that manages the USB connection with the only device that is connected to the phone, it's not finished by any means, but I'd like to get that reading part to work before I go any further.
public class UsbCommunicationManager
{
static final String ACTION_USB_PERMISSION = "com.android.example.USB_PERMISSION";
UsbManager usbManager;
UsbDevice usbDevice;
UsbInterface intf = null;
UsbEndpoint input, output;
UsbDeviceConnection connection;
PendingIntent permissionIntent;
Context context;
byte[] readBytes = new byte[64];
public UsbCommunicationManager(Context context)
{
this.context = context;
usbManager = (UsbManager) context.getSystemService(Context.USB_SERVICE);
// ask permission from user to use the usb device
permissionIntent = PendingIntent.getBroadcast(context, 0, new Intent(ACTION_USB_PERMISSION), 0);
IntentFilter filter = new IntentFilter(ACTION_USB_PERMISSION);
context.registerReceiver(usbReceiver, filter);
}
public void connect()
{
// check if there's a connected usb device
if(usbManager.getDeviceList().isEmpty())
{
Log.d("trebla", "No connected devices");
return;
}
// get the first (only) connected device
usbDevice = usbManager.getDeviceList().values().iterator().next();
// user must approve of connection
usbManager.requestPermission(usbDevice, permissionIntent);
}
public void stop()
{
context.unregisterReceiver(usbReceiver);
}
public String send(String data)
{
if(usbDevice == null)
{
return "no usb device selected";
}
int sentBytes = 0;
if(!data.equals(""))
{
synchronized(this)
{
// send data to usb device
byte[] bytes = data.getBytes();
sentBytes = connection.bulkTransfer(output, bytes, bytes.length, 1000);
}
}
return Integer.toString(sentBytes);
}
public String read()
{
// reinitialize read value byte array
Arrays.fill(readBytes, (byte) 0);
// wait for some data from the mcu
int recvBytes = connection.bulkTransfer(input, readBytes, readBytes.length, 3000);
if(recvBytes > 0)
{
Log.d("trebla", "Got some data: " + new String(readBytes));
}
else
{
Log.d("trebla", "Did not get any data: " + recvBytes);
}
return Integer.toString(recvBytes);
}
public String listUsbDevices()
{
HashMap<String, UsbDevice> deviceList = usbManager.getDeviceList();
if(deviceList.size() == 0)
{
return "no usb devices found";
}
Iterator<UsbDevice> deviceIterator = deviceList.values().iterator();
String returnValue = "";
UsbInterface usbInterface;
while(deviceIterator.hasNext())
{
UsbDevice device = deviceIterator.next();
returnValue += "Name: " + device.getDeviceName();
returnValue += "\nID: " + device.getDeviceId();
returnValue += "\nProtocol: " + device.getDeviceProtocol();
returnValue += "\nClass: " + device.getDeviceClass();
returnValue += "\nSubclass: " + device.getDeviceSubclass();
returnValue += "\nProduct ID: " + device.getProductId();
returnValue += "\nVendor ID: " + device.getVendorId();
returnValue += "\nInterface count: " + device.getInterfaceCount();
for(int i = 0; i < device.getInterfaceCount(); i++)
{
usbInterface = device.getInterface(i);
returnValue += "\n Interface " + i;
returnValue += "\n\tInterface ID: " + usbInterface.getId();
returnValue += "\n\tClass: " + usbInterface.getInterfaceClass();
returnValue += "\n\tProtocol: " + usbInterface.getInterfaceProtocol();
returnValue += "\n\tSubclass: " + usbInterface.getInterfaceSubclass();
returnValue += "\n\tEndpoint count: " + usbInterface.getEndpointCount();
for(int j = 0; j < usbInterface.getEndpointCount(); j++)
{
returnValue += "\n\t Endpoint " + j;
returnValue += "\n\t\tAddress: " + usbInterface.getEndpoint(j).getAddress();
returnValue += "\n\t\tAttributes: " + usbInterface.getEndpoint(j).getAttributes();
returnValue += "\n\t\tDirection: " + usbInterface.getEndpoint(j).getDirection();
returnValue += "\n\t\tNumber: " + usbInterface.getEndpoint(j).getEndpointNumber();
returnValue += "\n\t\tInterval: " + usbInterface.getEndpoint(j).getInterval();
returnValue += "\n\t\tType: " + usbInterface.getEndpoint(j).getType();
returnValue += "\n\t\tMax packet size: " + usbInterface.getEndpoint(j).getMaxPacketSize();
}
}
}
return returnValue;
}
private void setupConnection()
{
// find the right interface
for(int i = 0; i < usbDevice.getInterfaceCount(); i++)
{
// communications device class (CDC) type device
if(usbDevice.getInterface(i).getInterfaceClass() == UsbConstants.USB_CLASS_CDC_DATA)
{
intf = usbDevice.getInterface(i);
// find the endpoints
for(int j = 0; j < intf.getEndpointCount(); j++)
{
if(intf.getEndpoint(j).getDirection() == UsbConstants.USB_DIR_OUT && intf.getEndpoint(j).getType() == UsbConstants.USB_ENDPOINT_XFER_BULK)
{
// from android to device
output = intf.getEndpoint(j);
}
if(intf.getEndpoint(j).getDirection() == UsbConstants.USB_DIR_IN && intf.getEndpoint(j).getType() == UsbConstants.USB_ENDPOINT_XFER_BULK)
{
// from device to android
input = intf.getEndpoint(j);
}
}
}
}
}
private final BroadcastReceiver usbReceiver = new BroadcastReceiver()
{
public void onReceive(Context context, Intent intent)
{
String action = intent.getAction();
if(ACTION_USB_PERMISSION.equals(action))
{
// broadcast is like an interrupt and works asynchronously with the class, it must be synced just in case
synchronized(this)
{
if(intent.getBooleanExtra(UsbManager.EXTRA_PERMISSION_GRANTED, false))
{
setupConnection();
connection = usbManager.openDevice(usbDevice);
connection.claimInterface(intf, true);
// set flow control to 8N1 at 9600 baud
int baudRate = 9600;
byte stopBitsByte = 1;
byte parityBitesByte = 0;
byte dataBits = 8;
byte[] msg = {
(byte) (baudRate & 0xff),
(byte) ((baudRate >> 8) & 0xff),
(byte) ((baudRate >> 16) & 0xff),
(byte) ((baudRate >> 24) & 0xff),
stopBitsByte,
parityBitesByte,
(byte) dataBits
};
connection.controlTransfer(UsbConstants.USB_TYPE_CLASS | 0x01, 0x20, 0, 0, msg, msg.length, 5000);
}
else
{
Log.d("trebla", "Permission denied for USB device");
}
}
}
else if(UsbManager.ACTION_USB_DEVICE_DETACHED.equals(action))
{
Log.d("trebla", "USB device detached");
}
}
};
}
I keep getting -1 from the read() method which indicates some kind of error, it always times out. Maybe the problem comes from the connection configuration, I've tried several (read: trial and error) and none worked, surprisingly I don't need any configuration to send data to the device.
Edit
It must also be noted that the cable I'm using is micro-USB to micro-USB and it only works in one way, that is my device is powered by my phone only when the plug A connected to phone and plug B connected to device, not the other way around... it seems very strange. The fact that I'm able to send data and not receive when plugged the right way remains.
EDIT 2
I found that somebody else had the same problem but it seems he wasn't able to solve it.
EDIT 3
I finally found the solution on this page:
Another major oversight is that there is no mechanism for the host to notify the device that there is a data sink on the host side ready to accept data. This means that the device may try to send data while the host isn't listening, causing lengthy blocking timeouts in the transmission routines. It is thus highly recommended that the virtual serial line DTR (Data Terminal Ready) signal be used where possible to determine if a host application is ready for data.
So the DTR signal was mandatory and all I had to do was to add this to the interface configuration:
connection.controlTransfer(0x21, 0x22, 0x1, 0, null, 0, 0);
EDIT 4
If anybody is interested I finished the project and it's open source and published on my GitHub account. It's not stable all the time though (see the notes) and I don't plan working on it anymore, but it works. Feel free to use it for your own projects.

You can use UsbSerial Lib of from https://github.com/mik3y/usb-serial-for-android
My example code:
UsbManager usbManager = null;
UsbDeviceConnection connection = null;
UsbSerialDriver driver = null;
UsbSerialPort port = null;
usbManager = (UsbManager) context.getSystemService(Context.USB_SERVICE);
List<UsbSerialDriver> availableDrivers = UsbSerialProber.getDefaultProber().findAllDrivers(manager);
// Open a connection to the first available driver.
for (UsbSerialDriver usd : availableDrivers) {
UsbDevice udv = usd.getDevice();
if (udv.getVendorId()==0x067B || udv.getProductId()==2303){
driver = usd;
break;
}
}
connection = usbManager.openDevice(driver.getDevice());
port = driver.getPorts().get(0);
driver.getDevice().
}
if (connection == null) return;
try{
port.open(connection);
port.setParameters(4800, UsbSerialPort.DATABITS_8, UsbSerialPort.STOPBITS_1, UsbSerialPort.PARITY_NONE);
try{
byte buffer[] = new byte[250];
//Log.d("GPS_REQ", "->");
int numBytesRead = port.read(buffer, 500); //5000;
}catch (Exception e) {
Log.d("GPS_ERR", e.getLocalizedMessage());
}

VM aborting Getting error while running in emulator

I am using phonegap with socket programming.
When I check on emulator I am getting VM aborting error.
I am just calling my server and checking it to my emulator.
Here is my code.
package com.example.test;
import org.apache.cordova.DroidGap;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
public class MainActivity extends DroidGap {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//setContentView(R.layout.activity_main);
super.loadUrl("file:///android_asset/www/index.html");
appView.addJavascriptInterface(new WebSocketFactory(appView), "WebSocketFactory");
}
}
---------------------------------------------------------------------
package com.example.test;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.net.InetSocketAddress;
import java.net.URI;
import java.nio.ByteBuffer;
import java.nio.channels.NotYetConnectedException;
import java.nio.channels.SelectionKey;
import java.nio.channels.Selector;
import java.nio.channels.SocketChannel;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Iterator;
import java.util.Random;
import java.util.Set;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.LinkedBlockingQueue;
import android.util.Log;
import android.webkit.WebView;
public class WebSocket implements Runnable {
/**
* Enum for WebSocket Draft
*/
public enum Draft {
DRAFT75, DRAFT76
}
// //////////////// CONSTANT
/**
* The connection has not yet been established.
*/
public final static int WEBSOCKET_STATE_CONNECTING = 0;
/**
* The WebSocket connection is established and communication is possible.
*/
public final static int WEBSOCKET_STATE_OPEN = 1;
/**
* The connection is going through the closing handshake.
*/
public final static int WEBSOCKET_STATE_CLOSING = 2;
/**
* The connection has been closed or could not be opened.
*/
public final static int WEBSOCKET_STATE_CLOSED = 3;
/**
* An empty string
*/
private static String BLANK_MESSAGE = "";
/**
* The javascript method name for onOpen event.
*/
private static String EVENT_ON_OPEN = "onopen";
/**
* The javascript method name for onMessage event.
*/
private static String EVENT_ON_MESSAGE = "onmessage";
/**
* The javascript method name for onClose event.
*/
private static String EVENT_ON_CLOSE = "onclose";
/**
* The javascript method name for onError event.
*/
private static String EVENT_ON_ERROR = "onerror";
/**
* The default port of WebSockets, as defined in the spec.
*/
public static final int DEFAULT_PORT = 80;
/**
* The WebSocket protocol expects UTF-8 encoded bytes.
*/
public static final String UTF8_CHARSET = "UTF-8";
/**
* The byte representing Carriage Return, or \r
*/
public static final byte DATA_CR = (byte) 0x0D;
/**
* The byte representing Line Feed, or \n
*/
public static final byte DATA_LF = (byte) 0x0A;
/**
* The byte representing the beginning of a WebSocket text frame.
*/
public static final byte DATA_START_OF_FRAME = (byte) 0x00;
/**
* The byte representing the end of a WebSocket text frame.
*/
public static final byte DATA_END_OF_FRAME = (byte) 0xFF;
// //////////////// INSTANCE Variables
/**
* The WebView instance from Phonegap DroidGap
*/
private final WebView appView;
/**
* The unique id for this instance (helps to bind this to javascript events)
*/
private String id;
/**
* The URI this client is supposed to connect to.
*/
private URI uri;
/**
* The port of the websocket server
*/
private int port;
/**
* The Draft of the WebSocket protocol the Client is adhering to.
*/
private Draft draft;
/**
* The <tt>SocketChannel</tt> instance to use for this server connection.
* This is used to read and write data to.
*/
private SocketChannel socketChannel;
/**
* The 'Selector' used to get event keys from the underlying socket.
*/
private Selector selector;
/**
* Keeps track of whether or not the client thread should continue running.
*/
private boolean running;
/**
* Internally used to determine whether to recieve data as part of the
* remote handshake, or as part of a text frame.
*/
private boolean handshakeComplete;
/**
* The 1-byte buffer reused throughout the WebSocket connection to read
* data.
*/
private ByteBuffer buffer;
/**
* The bytes that make up the remote handshake.
*/
private ByteBuffer remoteHandshake;
/**
* The bytes that make up the current text frame being read.
*/
private ByteBuffer currentFrame;
/**
* Queue of buffers that need to be sent to the client.
*/
private BlockingQueue<ByteBuffer> bufferQueue;
/**
* Lock object to ensure that data is sent from the bufferQueue in the
* proper order
*/
private Object bufferQueueMutex = new Object();
/**
* Number 1 used in handshake
*/
private int number1 = 0;
/**
* Number 2 used in handshake
*/
private int number2 = 0;
/**
* Key3 used in handshake
*/
private byte[] key3 = null;
/**
* The readyState attribute represents the state of the connection.
*/
private int readyState = WEBSOCKET_STATE_CONNECTING;
private final WebSocket instance;
/**
* Constructor.
*
* Note: this is protected because it's supposed to be instantiated from {#link WebSocketFactory} only.
*
* #param appView
* {#link android.webkit.WebView}
* #param uri
* websocket server {#link URI}
* #param draft
* websocket server {#link Draft} implementation (75/76)
* #param id
* unique id for this instance
*/
protected WebSocket(WebView appView, URI uri, Draft draft, String id) {
this.appView = appView;
this.uri = uri;
this.draft = draft;
// port
port = uri.getPort();
if (port == -1) {
port = DEFAULT_PORT;
}
// Id
this.id = id;
this.bufferQueue = new LinkedBlockingQueue<ByteBuffer>();
this.handshakeComplete = false;
this.remoteHandshake = this.currentFrame = null;
this.buffer = ByteBuffer.allocate(1);
this.instance = this;
}
// //////////////////////////////////////////////////////////////////////////////////////
// /////////////////////////// WEB SOCKET API Methods
// ///////////////////////////////////
// //////////////////////////////////////////////////////////////////////////////////////
/**
* Starts a new Thread and connects to server
*
* #throws IOException
*/
public Thread connect() throws IOException {
this.running = true;
this.readyState = WEBSOCKET_STATE_CONNECTING;
// open socket
socketChannel = SocketChannel.open();
socketChannel.configureBlocking(false);
// set address
socketChannel.connect(new InetSocketAddress(uri.getHost(), port));
// start a thread to make connection
// More info:
// http://groups.google.com/group/android-developers/browse_thread/thread/45a8b53e9bf60d82
// http://stackoverflow.com/questions/2879455/android-2-2-and-bad-address-family-on-socket-connect
System.setProperty("java.net.preferIPv4Stack", "true");
System.setProperty("java.net.preferIPv6Addresses", "false");
selector = Selector.open();
socketChannel.register(selector, SelectionKey.OP_CONNECT);
Log.v("websocket", "Starting a new thread to manage data reading/writing");
Thread th = new Thread(this);
th.start();
// return thread object for explicit closing, if needed
return th;
}
public void run() {
while (this.running) {
try {
_connect();
} catch (IOException e) {
this.onError(e);
}
}
}
/**
* Closes connection with server
*/
public void close() {
this.readyState = WebSocket.WEBSOCKET_STATE_CLOSING;
// close socket channel
try {
this.socketChannel.close();
} catch (IOException e) {
this.onError(e);
}
this.running = false;
selector.wakeup();
// fire onClose method
this.onClose();
this.readyState = WebSocket.WEBSOCKET_STATE_CLOSED;
}
/**
* Sends <var>text</var> to server
*
* #param text
* String to send to server
*/
public void send(final String text) {
new Thread(new Runnable() {
#Override
public void run() {
if (instance.readyState == WEBSOCKET_STATE_OPEN) {
try {
instance._send(text);
} catch (IOException e) {
instance.onError(e);
}
} else {
instance.onError(new NotYetConnectedException());
}
}
}).start();
}
/**
* Called when an entire text frame has been received.
*
* #param msg
* Message from websocket server
*/
public void onMessage(final String msg) {
appView.post(new Runnable() {
#Override
public void run() {
appView.loadUrl(buildJavaScriptData(EVENT_ON_MESSAGE, msg));
}
});
}
public void onOpen() {
appView.post(new Runnable() {
#Override
public void run() {
appView.loadUrl(buildJavaScriptData(EVENT_ON_OPEN, BLANK_MESSAGE));
}
});
}
public void onClose() {
appView.post(new Runnable() {
#Override
public void run() {
appView.loadUrl(buildJavaScriptData(EVENT_ON_CLOSE, BLANK_MESSAGE));
}
});
}
public void onError(final Throwable t) {
appView.post(new Runnable() {
#Override
public void run() {
appView.loadUrl(buildJavaScriptData(EVENT_ON_ERROR, t.getMessage()));
}
});
}
public String getId() {
return id;
}
/**
* #return the readyState
*/
public int getReadyState() {
return readyState;
}
/**
* Builds text for javascript engine to invoke proper event method with
* proper data.
*
* #param event
* websocket event (onOpen, onMessage etc.)
* #param msg
* Text message received from websocket server
* #return
*/
private String buildJavaScriptData(String event, String msg) {
String _d = "javascript:WebSocket." + event + "(" + "{" + "\"_target\":\"" + id + "\"," + "\"data\":'" + msg.replaceAll("'", "\\\\'")
+ "'" + "}" + ")";
return _d;
}
// //////////////////////////////////////////////////////////////////////////////////////
// /////////////////////////// WEB SOCKET Internal Methods
// //////////////////////////////
// //////////////////////////////////////////////////////////////////////////////////////
private boolean _send(String text) throws IOException {
if (!this.handshakeComplete) {
throw new NotYetConnectedException();
}
if (text == null) {
throw new NullPointerException("Cannot send 'null' data to a WebSocket.");
}
// Get 'text' into a WebSocket "frame" of bytes
byte[] textBytes = text.getBytes(UTF8_CHARSET.toString());
ByteBuffer b = ByteBuffer.allocate(textBytes.length + 2);
b.put(DATA_START_OF_FRAME);
b.put(textBytes);
b.put(DATA_END_OF_FRAME);
b.rewind();
// See if we have any backlog that needs to be sent first
if (_write()) {
// Write the ByteBuffer to the socket
this.socketChannel.write(b);
}
// If we didn't get it all sent, add it to the buffer of buffers
if (b.remaining() > 0) {
if (!this.bufferQueue.offer(b)) {
throw new IOException("Buffers are full, message could not be sent to"
+ this.socketChannel.socket().getRemoteSocketAddress());
}
return false;
}
return true;
}
// actual connection logic
private void _connect() throws IOException {
// Continuous loop that is only supposed to end when "close" is called.
selector.select();
Set<SelectionKey> keys = selector.selectedKeys();
Iterator<SelectionKey> i = keys.iterator();
while (i.hasNext()) {
SelectionKey key = i.next();
i.remove();
if (key.isConnectable()) {
if (socketChannel.isConnectionPending()) {
socketChannel.finishConnect();
}
socketChannel.register(selector, SelectionKey.OP_READ);
_writeHandshake();
}
if (key.isReadable()) {
try {
_read();
} catch (NoSuchAlgorithmException nsa) {
this.onError(nsa);
}
}
}
}
private void _writeHandshake() throws IOException {
String path = this.uri.getPath();
if (path.indexOf("/") != 0) {
path = "/" + path;
}
String host = uri.getHost() + (port != DEFAULT_PORT ? ":" + port : "");
String origin = "*"; // TODO: Make 'origin' configurable
String request = "GET " + path + " HTTP/1.1\r\n" + "Upgrade: WebSocket\r\n" + "Connection: Upgrade\r\n"
+ "Host: " + host + "\r\n" + "Origin: " + origin + "\r\n";
// Add random keys for Draft76
if (this.draft == Draft.DRAFT76) {
request += "Sec-WebSocket-Key1: " + this._randomKey() + "\r\n";
request += "Sec-WebSocket-Key2: " + this._randomKey() + "\r\n";
request += "\r\n";
this.key3 = new byte[8];
(new Random()).nextBytes(this.key3);
// Convert to bytes early so last eight bytes don't get jacked
byte[] bRequest = request.getBytes(UTF8_CHARSET);
byte[] bToSend = new byte[bRequest.length + 8];
// Copy in the Request bytes
System.arraycopy(bRequest, 0, bToSend, 0, bRequest.length);
// Now tack on key3 bytes
System.arraycopy(this.key3, 0, bToSend, bRequest.length, this.key3.length);
// Now we can send all keys as a single frame
_write(bToSend);
return;
}
request += "\r\n";
_write(request.getBytes(UTF8_CHARSET));
}
private boolean _write() throws IOException {
synchronized (this.bufferQueueMutex) {
ByteBuffer buffer = this.bufferQueue.peek();
while (buffer != null) {
this.socketChannel.write(buffer);
if (buffer.remaining() > 0) {
return false; // Didn't finish this buffer. There's more to
// send.
} else {
this.bufferQueue.poll(); // Buffer finished. Remove it.
buffer = this.bufferQueue.peek();
}
}
return true;
}
}
private void _write(byte[] bytes) throws IOException {
this.socketChannel.write(ByteBuffer.wrap(bytes));
}
private void _read() throws IOException, NoSuchAlgorithmException {
this.buffer.rewind();
int bytesRead = -1;
try {
bytesRead = this.socketChannel.read(this.buffer);
} catch (Exception ex) {
}
if (bytesRead == -1) {
close();
} else if (bytesRead > 0) {
this.buffer.rewind();
if (!this.handshakeComplete) {
_readHandshake();
} else {
_readFrame();
}
}
}
private void _readFrame() throws UnsupportedEncodingException {
byte newestByte = this.buffer.get();
if (newestByte == DATA_START_OF_FRAME) { // Beginning of Frame
this.currentFrame = null;
} else if (newestByte == DATA_END_OF_FRAME) { // End of Frame
String textFrame = null;
// currentFrame will be null if END_OF_FRAME was send directly after
// START_OF_FRAME, thus we will send 'null' as the sent message.
if (this.currentFrame != null) {
textFrame = new String(this.currentFrame.array(), "ISO-8859-1");
}
// fire onMessage method
this.onMessage(textFrame);
} else { // Regular frame data, add to current frame buffer
ByteBuffer frame = ByteBuffer.allocate((this.currentFrame != null ? this.currentFrame.capacity() : 0)
+ this.buffer.capacity());
if (this.currentFrame != null) {
this.currentFrame.rewind();
frame.put(this.currentFrame);
}
frame.put(newestByte);
this.currentFrame = frame;
String textFrame = new String(this.currentFrame.array(),"ISO-8859-1");
this.onMessage(textFrame);
}
}
private void _readHandshake() throws IOException, NoSuchAlgorithmException {
ByteBuffer ch = ByteBuffer.allocate((this.remoteHandshake != null ? this.remoteHandshake.capacity() : 0)
+ this.buffer.capacity());
if (this.remoteHandshake != null) {
this.remoteHandshake.rewind();
ch.put(this.remoteHandshake);
}
ch.put(this.buffer);
this.remoteHandshake = ch;
byte[] h = this.remoteHandshake.array();
// If the ByteBuffer contains 16 random bytes, and ends with
// 0x0D 0x0A 0x0D 0x0A (or two CRLFs), then the client
// handshake is complete for Draft 76 Client.
if ((h.length >= 20 && h[h.length - 20] == DATA_CR && h[h.length - 19] == DATA_LF
&& h[h.length - 18] == DATA_CR && h[h.length - 17] == DATA_LF)) {
_readHandshake(new byte[] { h[h.length - 16], h[h.length - 15], h[h.length - 14], h[h.length - 13],
h[h.length - 12], h[h.length - 11], h[h.length - 10], h[h.length - 9], h[h.length - 8],
h[h.length - 7], h[h.length - 6], h[h.length - 5], h[h.length - 4], h[h.length - 3],
h[h.length - 2], h[h.length - 1] });
// If the ByteBuffer contains 8 random bytes,ends with
// 0x0D 0x0A 0x0D 0x0A (or two CRLFs), and the response
// contains Sec-WebSocket-Key1 then the client
// handshake is complete for Draft 76 Server.
} else if ((h.length >= 12 && h[h.length - 12] == DATA_CR && h[h.length - 11] == DATA_LF
&& h[h.length - 10] == DATA_CR && h[h.length - 9] == DATA_LF)
&& new String(this.remoteHandshake.array(), UTF8_CHARSET).contains("Sec-WebSocket-Key1")) {// ************************
_readHandshake(new byte[] { h[h.length - 8], h[h.length - 7], h[h.length - 6], h[h.length - 5],
h[h.length - 4], h[h.length - 3], h[h.length - 2], h[h.length - 1] });
// Consider Draft 75, and the Flash Security Policy
// Request edge-case.
} else if ((h.length >= 4 && h[h.length - 4] == DATA_CR && h[h.length - 3] == DATA_LF
&& h[h.length - 2] == DATA_CR && h[h.length - 1] == DATA_LF)
&& !(new String(this.remoteHandshake.array(), UTF8_CHARSET).contains("Sec"))
|| (h.length == 23 && h[h.length - 1] == 0)) {
_readHandshake(null);
}else{
_readHandshake(null);
}
}
private void _readHandshake(byte[] handShakeBody) throws IOException, NoSuchAlgorithmException {
// byte[] handshakeBytes = this.remoteHandshake.array();
// String handshake = new String(handshakeBytes, UTF8_CHARSET);
// TODO: Do some parsing of the returned handshake, and close connection
// in received anything unexpected!
this.handshakeComplete = true;
boolean isConnectionReady = true;
if (this.draft == WebSocket.Draft.DRAFT76) {
if (handShakeBody == null) {
isConnectionReady = true;
} else{
byte[] challenge = new byte[] { (byte) (this.number1 >> 24), (byte) ((this.number1 << 8) >> 24),
(byte) ((this.number1 << 16) >> 24), (byte) ((this.number1 << 24) >> 24),
(byte) (this.number2 >> 24), (byte) ((this.number2 << 8) >> 24),
(byte) ((this.number2 << 16) >> 24), (byte) ((this.number2 << 24) >> 24), this.key3[0],
this.key3[1], this.key3[2], this.key3[3], this.key3[4], this.key3[5], this.key3[6], this.key3[7] };
MessageDigest md5 = MessageDigest.getInstance("MD5");
byte[] expected = md5.digest(challenge);
for (int i = 0; i < handShakeBody.length; i++) {
if (expected[i] != handShakeBody[i]) {
isConnectionReady = true;
}
}
}
}
if (isConnectionReady) {
this.readyState = WEBSOCKET_STATE_OPEN;
// fire onOpen method
this.onOpen();
} else {
close();
}
}
private String _randomKey() {
Random r = new Random();
long maxNumber = 4294967295L;
long spaces = r.nextInt(12) + 1;
int max = new Long(maxNumber / spaces).intValue();
max = Math.abs(max);
int number = r.nextInt(max) + 1;
if (this.number1 == 0) {
this.number1 = number;
} else {
this.number2 = number;
}
long product = number * spaces;
String key = Long.toString(product);
int numChars = r.nextInt(12);
for (int i = 0; i < numChars; i++) {
int position = r.nextInt(key.length());
position = Math.abs(position);
char randChar = (char) (r.nextInt(95) + 33);
// exclude numbers here
if (randChar >= 48 && randChar <= 57) {
randChar -= 15;
}
key = new StringBuilder(key).insert(position, randChar).toString();
}
for (int i = 0; i < spaces; i++) {
int position = r.nextInt(key.length() - 1) + 1;
position = Math.abs(position);
key = new StringBuilder(key).insert(position, "\u0020").toString();
}
return key;
}
}
----------------------------------------------------------------------------
package com.example.test;
import java.net.URI;
import java.util.Random;
import android.webkit.WebView;
/**
* The <tt>WebSocketFactory</tt> is like a helper class to instantiate new
* WebSocket instaces especially from Javascript side. It expects a valid
* "ws://" URI.
*
* #author Animesh Kumar
*/
public class WebSocketFactory {
/** The app view. */
WebView appView;
/**
* Instantiates a new web socket factory.
*
* #param appView
* the app view
*/
public WebSocketFactory(WebView appView) {
this.appView = appView;
}
public WebSocket getInstance(String url) {
// use Draft75 by default
return getInstance(url, WebSocket.Draft.DRAFT76);
}
public WebSocket getInstance(String url, WebSocket.Draft draft) {
WebSocket socket = null;
Thread th = null;
try {
socket = new WebSocket(appView, new URI(url), draft, getRandonUniqueId());
th = socket.connect();
return socket;
} catch (Exception e) {
//Log.v("websocket", e.toString());
if(th != null) {
th.interrupt();
}
}
return null;
}
/**
* Generates random unique ids for WebSocket instances
*
* #return String
*/
private String getRandonUniqueId() {
return "WEBSOCKET." + new Random().nextInt(100);
}
}
-------------------------------------------------------------
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<meta name="format-detection" content="telephone=no" />
<meta name="viewport" content="user-scalable=no, initial-scale=1, maximum-scale=1, minimum-scale=1, width=device-width, height=device-height, target-densitydpi=device-dpi" />
<link rel="stylesheet" type="text/css" href="css/index.css" />
<title>Hello World</title>
</head>
<body>
<script type="text/javascript" src="cordova-2.7.0.js"></script>
<script type="text/javascript" src="js/index.js"></script>
<script type="text/javascript" src="js/websocket.js"></script>
<script type="text/javascript">
var socket = new WebSocket('ws://192.168.1.3:8101/');
// push a message after the connection is established.
socket.onopen = function() {
socket.send('Hello World')
};
// alerts message pushed from server
socket.onmessage = function(msg) {
console.log("TTTTT"+JSON.stringify(msg));
};
// alert close event
socket.onclose = function() {
alert('closed');
};
</script>
</body>
</html>
From the script I am calling my functions.
But when I check it on emulator it is showing that error.
Please help me removing this error.
Thanks.

Android ADK with PC as USB Host with libusb, bulk transfer error

I'm trying to make my PC the USB Host for Android 2.3.4 devices in order to be able to develop APIs without needing actual "accessories". To do this, I need to establish the PC as the USB Host and the "device" (in my case a Nexus One running 2.3.4).
I started with libusb code from http://android.serverbox.ch/ as a base for the PC side and the DemoKit code and Android documentation on the Android side.
The two seems to negotiate the connection fine, and the interface gets "claimed" but dies on the actual attempt at bulk transfer. On OSX, the error is -5 (LIBUSB_ERROR_NOT_FOUND) and on Ubuntu Linux (as root) the error is -1 (LIBUSB_ERROR_IO). (Most recent releases of each with most recent libusb 1.0.8).
Here's the code. Other comments on problems welcome, though this is mostly a proof-of-concept, so I'm really just looking for the reason the bulk transfer isn't working:
#include <stdio.h>
#include <libusb.h>
#include <string.h>
#define ENDPOINT_BULK_IN 0x83
#define ENDPOINT_BULK_OUT 0x03 // Have tried 0x00, 0x01 and 0x02
#define VID 0x18D1
#define PID 0x4E11
#define ACCESSORY_PID 0x2D00
#define ACCESSORY_ADB_PID 0x2D01 // Can't get this to work, if ADB is active, can't get handle on device
/*
ON OSX
gcc adktest.c -I/usr/local/include -o adktest -lusb-1.0.0 -I/usr/local/include -I/usr/local/include/libusb-1.0
ON UBUNTU
gcc adktest.c -I/usr/include -o adktest -lusb-1.0 -I/usr/include -I/usr/include/libusb-1.0
Testing on Nexus One with Gingerbread 2.3.4
*/
static int transferTest();
static int init(void);
static int shutdown(void);
static void error(int code);
static void status(int code);
static int setupAccessory(
const char* manufacturer,
const char* modelName,
const char* description,
const char* version,
const char* uri,
const char* serialNumber);
//static
static struct libusb_device_handle* handle;
int main (int argc, char *argv[]){
if(init() < 0)
return;
if(setupAccessory(
"PCHost",
"PCHost1",
"Description",
"1.0",
"http://www.mycompany.com",
"SerialNumber") < 0){
fprintf(stdout, "Error setting up accessory\n");
shutdown();
return -1;
};
if(transferTest() < 0){
fprintf(stdout, "Error in transferTest\n");
shutdown();
return -1;
}
shutdown();
fprintf(stdout, "Finished\n");
return 0;
}
static int transferTest(){
// TEST BULK IN/OUT
const static int PACKET_BULK_LEN=64;
const static int TIMEOUT=5000;
int r,i;
int transferred;
char answer[PACKET_BULK_LEN];
char question[PACKET_BULK_LEN];
for (i=0;i<PACKET_BULK_LEN; i++) question[i]=i;
// ***FAILS HERE***
r = libusb_bulk_transfer(handle, ENDPOINT_BULK_OUT, question, PACKET_BULK_LEN,
&transferred,TIMEOUT);
if (r < 0) {
fprintf(stderr, "Bulk write error %d\n", r);
error(r);
return r;
}
fprintf(stdout, "Wrote %d bytes", r);
r = libusb_bulk_transfer(handle, ENDPOINT_BULK_IN, answer,PACKET_BULK_LEN,
&transferred, TIMEOUT);
if (r < 0) {
fprintf(stderr, "Bulk read error %d\n", r);
error(r);
return r;
}
fprintf(stdout, "Read %d bytes", r);
if (transferred < PACKET_BULK_LEN) {
fprintf(stderr, "Bulk transfer short read (%d)\n", r);
error(r);
return -1;
}
printf("Bulk Transfer Loop Test Result:\n");
// for (i=0;i< PACKET_BULK_LEN;i++) printf("%i, %i,\n ",question[i],answer[i]);
for(i = 0;i < PACKET_BULK_LEN; i++) {
if(i%8 == 0)
printf("\n");
printf("%02x, %02x; ",question[i],answer[i]);
}
printf("\n\n");
return 0;
}
static int init(){
libusb_init(NULL);
if((handle = libusb_open_device_with_vid_pid(NULL, VID, PID)) == NULL){
fprintf(stdout, "Problem acquiring handle\n");
return -1;
}
libusb_claim_interface(handle, 0);
return 0;
}
static int shutdown(){
if(handle != NULL)
libusb_release_interface (handle, 0);
libusb_exit(NULL);
return 0;
}
static int setupAccessory(
const char* manufacturer,
const char* modelName,
const char* description,
const char* version,
const char* uri,
const char* serialNumber){
unsigned char ioBuffer[2];
int devVersion;
int response;
response = libusb_control_transfer(
handle, //handle
0xC0, //bmRequestType
51, //bRequest
0, //wValue
0, //wIndex
ioBuffer, //data
2, //wLength
0 //timeout
);
if(response < 0){error(response);return-1;}
devVersion = ioBuffer[1] << 8 | ioBuffer[0];
fprintf(stdout,"Version Code Device: %d\n", devVersion);
usleep(1000);//sometimes hangs on the next transfer :(
response = libusb_control_transfer(handle,0x40,52,0,0,(char*)manufacturer,strlen(manufacturer),0);
if(response < 0){error(response);return -1;}
response = libusb_control_transfer(handle,0x40,52,0,1,(char*)modelName,strlen(modelName)+1,0);
if(response < 0){error(response);return -1;}
response = libusb_control_transfer(handle,0x40,52,0,2,(char*)description,strlen(description)+1,0);
if(response < 0){error(response);return -1;}
response = libusb_control_transfer(handle,0x40,52,0,3,(char*)version,strlen(version)+1,0);
if(response < 0){error(response);return -1;}
response = libusb_control_transfer(handle,0x40,52,0,4,(char*)uri,strlen(uri)+1,0);
if(response < 0){error(response);return -1;}
response = libusb_control_transfer(handle,0x40,52,0,5,(char*)serialNumber,strlen(serialNumber)+1,0);
if(response < 0){error(response);return -1;}
fprintf(stdout,"Accessory Identification sent\n", devVersion);
response = libusb_control_transfer(handle,0x40,53,0,0,NULL,0,0);
if(response < 0){error(response);return -1;}
fprintf(stdout,"Attempted to put device into accessory mode\n", devVersion);
if(handle != NULL)
libusb_release_interface (handle, 0);
int tries = 4;
for(;;){
tries--;
if((handle = libusb_open_device_with_vid_pid(NULL, VID, ACCESSORY_PID)) == NULL){
if(tries < 0){
return -1;
}
}else{
break;
}
sleep(1);
}
libusb_claim_interface(handle, 0);
fprintf(stdout, "Interface claimed, ready to transfer data\n");
return 0;
}
// error reporting function left out for brevity
And here's the Android app:
package com.cengen.android.pchost;
import android.app.Activity;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.os.ParcelFileDescriptor;
import com.android.future.usb.UsbAccessory;
import com.android.future.usb.UsbManager;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.FileDescriptor;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
public class MainActivity extends Activity implements Runnable
{
private final Logger logger = LoggerFactory.getLogger("PCHost");
private UsbManager usbManager;
UsbAccessory accessory;
ParcelFileDescriptor accessoryFileDescriptor;
FileInputStream accessoryInput;
FileOutputStream accessoryOutput;
private final BroadcastReceiver usbBroadcastReceiver = new BroadcastReceiver()
{
public void onReceive(Context context, Intent intent)
{
String action = intent.getAction();
if (UsbManager.ACTION_USB_ACCESSORY_ATTACHED.equals(action))
{
synchronized (this)
{
accessory = UsbManager.getAccessory(intent);
}
}
else if (UsbManager.ACTION_USB_ACCESSORY_DETACHED.equals(action))
{
UsbAccessory accessory = UsbManager.getAccessory(intent);
if (accessory != null)
{
// call your method that cleans up and closes communication with the accessory
}
}
}
};
Handler messageHandler = new Handler()
{
#Override
public void handleMessage(Message msg)
{
switch (msg.what)
{
case 1:
logger.info("Got message type {}", msg.what);
// SendFileMessage m = (SendFileMessage) msg.obj;
// handleSendFile(m);
break;
case 2:
logger.info("Got message type {}", msg.what);
// SendFileMessage m = (SendFileMessage) msg.obj;
// handleSendFile(m);
break;
case 3:
logger.info("Got message type {}", msg.what);
// SendFileMessage m = (SendFileMessage) msg.obj;
// handleSendFile(m);
break;
}
}
};
/**
* Main USB reading loop, processing incoming data from accessory and parsing
* it into messages via the defined format.
*/
public void run()
{
int ret = 0;
byte[] buffer = new byte[16384];
int i;
while (ret >= 0)
{
try
{
ret = accessoryInput.read(buffer);
logger.debug("Read {} bytes.", ret);
}
catch (IOException e)
{
logger.debug("Exception in USB accessory input reading", e);
break;
}
i = 0;
while (i < ret)
{
int len = ret - i;
switch (buffer[i])
{
case 0x1:
if (len >= 3)
{
Message m = Message.obtain(messageHandler, 1);
// m.obj = new MessageTypeOne(buffer[i + 1], buffer[i + 2]);
messageHandler.sendMessage(m);
}
i += 3;
break;
case 0x4:
if (len >= 3)
{
Message m = Message.obtain(messageHandler, 1);
// m.obj = new MessageTypeTwo(buffer[i + 1], buffer[i + 2]);
messageHandler.sendMessage(m);
}
i += 3;
break;
default:
logger.debug("unknown msg: " + buffer[i]);
i = len;
break;
}
}
}
}
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
usbManager = UsbManager.getInstance(this);
IntentFilter filter = new IntentFilter(UsbManager.ACTION_USB_ACCESSORY_ATTACHED);
filter.addAction(UsbManager.ACTION_USB_ACCESSORY_DETACHED);
registerReceiver(usbBroadcastReceiver, filter);
if (getLastNonConfigurationInstance() != null)
{
accessory = (UsbAccessory) getLastNonConfigurationInstance();
openAccessory(accessory);
}
setContentView(R.layout.main);
}
#Override
public Object onRetainNonConfigurationInstance()
{
return accessory != null ? accessory : super.onRetainNonConfigurationInstance();
}
#Override
public void onResume()
{
super.onResume();
Intent intent = getIntent();
if (accessoryInput != null && accessoryOutput != null)
return;
// TODO: verify, docs don't do this simple thing, not sure why?
UsbAccessory accessory = UsbManager.getAccessory(intent);
if (accessory != null)
openAccessory(accessory);
else
logger.error("Failed to resume accessory.");
}
#Override
public void onPause()
{
super.onPause();
closeAccessory();
}
#Override
public void onDestroy()
{
unregisterReceiver(usbBroadcastReceiver);
super.onDestroy();
}
private void openAccessory(UsbAccessory accessory)
{
accessoryFileDescriptor = usbManager.openAccessory(accessory);
if (accessoryFileDescriptor != null)
{
this.accessory = accessory;
FileDescriptor fd = accessoryFileDescriptor.getFileDescriptor();
accessoryInput = new FileInputStream(fd);
accessoryOutput = new FileOutputStream(fd);
Thread thread = new Thread(null, this, "AndroidPCHost");
thread.start();
logger.debug("accessory opened");
// TODO: enable USB operations in the app
}
else
{
logger.debug("accessory open fail");
}
}
private void closeAccessory()
{
// TODO: disable USB operations in the app
try
{
if (accessoryFileDescriptor != null)
accessoryFileDescriptor.close();
}
catch (IOException e)
{}
finally
{
accessoryFileDescriptor = null;
accessory = null;
}
}
}
And the manifest (including the intent-filtering so it auto-associates and auto-perms the device, according to the docs):
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.mycompany.android.pchost"
android:versionCode="1"
android:versionName="1.0">
<uses-feature android:name="android.hardware.usb.accessory" />
<uses-sdk android:minSdkVersion="10" />
<application android:label="#string/app_name" android:icon="#drawable/icon">
<uses-library android:name="com.android.future.usb.accessory" />
<activity android:name="MainActivity"
android:label="#string/app_name"
android:launchMode="singleInstance">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
<intent-filter>
<action android:name="android.hardware.usb.action.USB_ACCESSORY_ATTACHED" />
</intent-filter>
<meta-data android:name="android.hardware.usb.action.USB_ACCESSORY_ATTACHED"
android:resource="#xml/accessory_filter" />
</activity>
</application>
</manifest>

Initial problem is that the original connection to the device in order to tell it to go into accessory mode is never closed. The USB subsystem and/or libusb do not throw an error if you then reopen and claim an interface while the original device is still left open. You only get an IO or NOT FOUND error when you actually try to write to/from an endpoint.
By adding:
libusb_close(handle);
within the if statement where the initial interface is released from initial connection the libusb side of the issue is resolved.
The next issue that prevents data to pass in this particular combination of softwares, is that the Android side is waiting for a larger segment of bytes before it accepts the read which results in a timeout (haven't worked out due to which side yet) and so if you set the buffer to match the libusb side (64), you will get an initial set of bytes written from the PC to the Android device. The software will still break after that since the PC/libusb side then tries to read data but the Android side isn't writing any, but that is simply unfinished software and not within the scope of the question.

The code example is very helpful, it just needs some modifications to work on Windows using libusb and installing WinUSB drivers via Zadig.
#include <stdio.h>
#include <libusb.h>
#include <string.h>
#ifdef _WIN32
#include <Windows.h>
#define sleep Sleep
#else
#include <unistd.h>
#endif
#define ENDPOINT_BULK_IN 0x83
#define ENDPOINT_BULK_OUT 0x03 // Have tried 0x00, 0x01 and 0x02
#define VID 0x18D1
#define PID 0x4E11
#define ACCESSORY_PID 0x2D00
#define ACCESSORY_ADB_PID 0x2D01 // Can't get this to work, if ADB is active, can't get handle on device
#define PACKET_BULK_LEN 64
#define TIMEOUT 5000
static int transferTest(void);
static int setupAccessory(
const char* manufacturer,
const char* modelName,
const char* description,
const char* version,
const char* uri,
const char* serialNumber);
//static
static struct libusb_device_handle* handle;
int main (int argc, char *argv[])
{
int r, tries;
libusb_init(NULL);
if((handle = libusb_open_device_with_vid_pid(NULL, VID, PID)) != NULL)
{
libusb_claim_interface(handle, 0);
r = setupAccessory("PCHost",
"PCHost1",
"Description",
"1.0",
"http://www.mycompany.com",
"SerialNumber");
libusb_release_interface (handle, 0);
libusb_close(handle);
if (r < 0)
{
libusb_exit(NULL);
fprintf(stdout, "Error setting up accessory\n");
return -1;
}
}
tries = 4;
for(;;)
{
tries--;
if((handle = libusb_open_device_with_vid_pid(NULL, VID, ACCESSORY_PID)) == NULL)
{
if(tries < 0)
{
libusb_exit(NULL);
fprintf(stdout, "Problem acquiring handle\n");
return -1;
}
}
else
{
break;
}
sleep(1);
}
libusb_claim_interface(handle, 0);
fprintf(stdout, "Interface claimed, ready to transfer data\n");
r = transferTest();
libusb_release_interface (handle, 0);
libusb_close(handle);
libusb_exit(NULL);
if (r < 0)
{
fprintf(stdout, "Error in transferTest\n");
return -1;
}
fprintf(stdout, "Finished\n");
return 0;
}
static int transferTest(void)
{
// TEST BULK IN/OUT
int r,i;
int transferred;
unsigned char answer[PACKET_BULK_LEN];
unsigned char question[PACKET_BULK_LEN];
struct libusb_device* device;
struct libusb_config_descriptor* config;
struct libusb_interface_descriptor const* interfaceDesc;
unsigned char epInAddr = ENDPOINT_BULK_IN;
unsigned char epOutAddr = ENDPOINT_BULK_OUT;
unsigned char idx;
for (i=0;i<PACKET_BULK_LEN; i++)
question[i]=(unsigned char)i;
device = libusb_get_device(handle);
r = libusb_get_active_config_descriptor(device, &config);
if (r < 0)
{
fprintf(stderr, "No active descriptor error %d\n", r);
return r;
}
interfaceDesc = config->interface[0].altsetting;
for(idx = 0; idx < interfaceDesc->bNumEndpoints; idx++)
{
if ((interfaceDesc->endpoint[idx].bmAttributes & LIBUSB_TRANSFER_TYPE_MASK) == LIBUSB_TRANSFER_TYPE_BULK)
{
if ((interfaceDesc->endpoint[idx].bEndpointAddress & LIBUSB_ENDPOINT_IN) == LIBUSB_ENDPOINT_IN)
{
epInAddr = interfaceDesc->endpoint[idx].bEndpointAddress;
}
else
{
epOutAddr = interfaceDesc->endpoint[idx].bEndpointAddress;
}
}
}
r = libusb_bulk_transfer(handle, epOutAddr, question, PACKET_BULK_LEN,
&transferred,TIMEOUT);
if (r < 0)
{
fprintf(stderr, "Bulk write error %d\n", r);
return r;
}
fprintf(stdout, "Wrote %d bytes", r);
r = libusb_bulk_transfer(handle, epInAddr, answer,PACKET_BULK_LEN,
&transferred, TIMEOUT);
if (r < 0)
{
fprintf(stderr, "Bulk read error %d\n", r);
return r;
}
fprintf(stdout, "Read %d bytes", r);
if (transferred < PACKET_BULK_LEN)
{
fprintf(stderr, "Bulk transfer short read (%d)\n", r);
return -1;
}
printf("Bulk Transfer Loop Test Result:\n");
for(i = 0; i < PACKET_BULK_LEN; i++)
{
if(i%8 == 0)
printf("\n");
printf("%02x, %02x; ",question[i],answer[i]);
}
printf("\n\n");
return 0;
}
static int setupAccessory(
const char* manufacturer,
const char* modelName,
const char* description,
const char* version,
const char* uri,
const char* serialNumber)
{
unsigned char ioBuffer[2];
int devVersion;
int r;
r = libusb_control_transfer(
handle, //handle
0xC0, //bmRequestType
51, //bRequest
0, //wValue
0, //wIndex
ioBuffer, //data
2, //wLength
0 //timeout
);
if(r < 0)
{
return-1;
}
devVersion = ioBuffer[1] << 8 | ioBuffer[0];
fprintf(stdout,"Version Code Device: %d\n", devVersion);
sleep(1); //sometimes hangs on the next transfer :(
if ((libusb_control_transfer(handle,0x40,52,0,0,(unsigned char*)manufacturer,strlen(manufacturer)+1,0) < 0) ||
(libusb_control_transfer(handle,0x40,52,0,1,(unsigned char*)modelName,strlen(modelName)+1,0) < 0) ||
(libusb_control_transfer(handle,0x40,52,0,2,(unsigned char*)description,strlen(description)+1,0) < 0) ||
(libusb_control_transfer(handle,0x40,52,0,3,(unsigned char*)version,strlen(version)+1,0) < 0) ||
(libusb_control_transfer(handle,0x40,52,0,4,(unsigned char*)uri,strlen(uri)+1,0) < 0) ||
(libusb_control_transfer(handle,0x40,52,0,5,(unsigned char*)serialNumber,strlen(serialNumber)+1,0) < 0))
{
return -1;
}
fprintf(stdout,"Accessory Identification sent\n", devVersion);
r = libusb_control_transfer(handle,0x40,53,0,0,NULL,0,0);
if(r < 0)
{
return -1;
}
fprintf(stdout,"Attempted to put device into accessory mode\n", devVersion);
return 0;
}
Besides some refactoring and adding the necessary libusb_close(handle) calls mentioned in #ColinM's answer this is mainly adding:
Enumeration over the available end-points
Assumes the device is already in accessory mode if initial PID/VID not found