I want to add reference to DNSSDObjects to a project in MonoTouch, specifically DNSServiceResolve object.
I want to access DNSServiceResolve in a MonoTouch project but cant find that class anywhere.
How can that be done ?
I got the functions from dns_sd.h working with P/Invokes. Most of the definitions were already done in the project zeroconfignetservices [1], specifically in the file mDNSImports.cs. Instead of referencing dnssd.dll, it is /usr/lib/system/libsystem_dnssd.dylib on iOS.
So for example, the definition for DNSServiceQueryRecord would be:
[DllImport("/usr/lib/system/libsystem_dnssd.dylib")]
public static extern DNSServiceErrorType DNSServiceQueryRecord(out IntPtr sdRef,
DNSServiceFlags flags,
UInt32 interfaceIndex,
[MarshalAs(
UnmanagedType.CustomMarshaler,
MarshalTypeRef = typeof(Utf8Marshaler))] String fullname,
DNSServiceType rrType,
DNSServiceClass rrClass,
DNSServiceQueryReply callBack,
IntPtr context);
And a query for an SRV record would be as follows:
public void DoDnsLookup()
{
IntPtr sdRef;
var result = DNSServiceQueryRecord(
out sdRef,
DNSServiceFlags.LongLivedQuery,
0,
"_xmpp-client._tcp.gmail.com",
DNSServiceType.SRV,
DNSServiceClass.IN,
DnsServiceQueryReply,
IntPtr.Zero
);
if (result == DNSServiceErrorType.NoError)
{
DNSServiceProcessResult(sdRef);
DNSServiceRefDeallocate(sdRef);
}
}
//see [2] why this method is static and the attribute
[MonoPInvokeCallback(typeof(DNSServiceQueryReply))]
public static void DnsServiceQueryReply(
IntPtr sdRef,
DNSServiceFlags flags,
UInt32 interfaceIndex,
DNSServiceErrorType errorCode,
[MarshalAs(
UnmanagedType.CustomMarshaler,
MarshalTypeRef = typeof(Utf8Marshaler))] String fullname,
DNSServiceType rrType,
DNSServiceClass rrClass,
UInt16 rdLength,
[MarshalAs(UnmanagedType.LPArray, SizeParamIndex = 7)]byte[] rData,
UInt32 ttl,
IntPtr context)
{
if (result == DNSServiceErrorType.NoError)
{
// process returned DNS data in rData
// a useful library for this could be Bdev.Net.Dns [3]
}
}
All the classes, enums, etc. not defined here are from [1].
References:
http://code.google.com/p/zeroconfignetservices
http://docs.xamarin.com/ios/guides/advanced_topics/limitations#Reverse_Callbacks
dnslookup.codeplex.com
Related
Is it possible to access OpenGL ES on iOS from RoboVM without using LibGDX? If so, are there any useful references?
The only thing I can find is this super-simple demo from over 2 years ago: http://robovm.com/ios-opengles-in-java-on-robovm/
But it doesn't provide any functions besides glClearColor and glClear.
The Apple GLKit framework seems to be implemented, though. I just can't find all the actual glWhatever(...) functions...
Yes, it is possible. You need two things for this: 1. Access to the OpenGL ES functions (like glClear(...), etc.) and 2. a UIView in your app that can draw the GL image.
Turns out the second point is very easy. You can either use a GLKView (requires iOS 5.0) or a CAEAGLLayer (requires iOS 2.0) if you're feeling nostalgic. For both, there are tons of tutorials online on how to use them in Objective-C, which can readily be translated to RoboVM. So, I won't spend too much time on this point here.
Access to the OpenGL ES functions is a little more difficult, as RoboVM doesn't ship with the definitions file out of the box. So, we'll have to build our own using Bro. Turns out, once you wrap your head around how Bro handles C-strings, variable pointers, IntBuffers and such (which is actually quite beautiful!), it's really pretty straight forward. The super-simple demo I linked to in the original question is the right starting point.
In the interest of brevity, let me post here just a very abridged version of the file I wrote to illustrate the way the different data types can be handled:
import java.nio.Buffer;
import java.nio.IntBuffer;
import org.robovm.rt.bro.Bro;
import org.robovm.rt.bro.Struct;
import org.robovm.rt.bro.annotation.Bridge;
import org.robovm.rt.bro.annotation.Library;
import org.robovm.rt.bro.ptr.BytePtr;
import org.robovm.rt.bro.ptr.BytePtr.BytePtrPtr;
import org.robovm.rt.bro.ptr.IntPtr;
#Library("OpenGLES")
public class GLES20 {
public static final int GL_DEPTH_BUFFER_BIT = 0x00000100;
public static final int GL_STENCIL_BUFFER_BIT = 0x00000400;
public static final int GL_COLOR_BUFFER_BIT = 0x00004000;
public static final int GL_FALSE = 0;
public static final int GL_TRUE = 1;
private static final int MAX_INFO_LOG_LENGTH = 10*1024;
private static final ThreadLocal<IntPtr> SINGLE_VALUE =
new ThreadLocal<IntPtr>() {
#Override
protected IntPtr initialValue() {
return Struct.allocate(IntPtr.class, 1);
}
};
private static final ThreadLocal<BytePtr> INFO_LOG =
new ThreadLocal<BytePtr>() {
#Override
protected BytePtr initialValue() {
return Struct.allocate(BytePtr.class, MAX_INFO_LOG_LENGTH);
}
};
static {
Bro.bind(GLES20.class);
}
#Bridge
public static native void glClearColor(float red, float green, float blue, float alpha);
#Bridge
public static native void glClear(int mask);
#Bridge
public static native void glGetIntegerv(int pname, IntPtr params);
// DO NOT CALL THE NEXT METHOD WITH A pname THAT RETURNS MORE THAN ONE VALUE!!!
public static int glGetIntegerv(int pname) {
IntPtr params = SINGLE_VALUE.get();
glGetIntegerv(pname, params);
return params.get();
}
#Bridge
private static native int glGetUniformLocation(int program, BytePtr name);
public static int glGetUniformLocation(int program, String name) {
return glGetUniformLocation(program, BytePtr.toBytePtrAsciiZ(name));
}
#Bridge
public static native int glGenFramebuffers(int n, IntPtr framebuffers);
public static int glGenFramebuffer() {
IntPtr framebuffers = SINGLE_VALUE.get();
glGenFramebuffers(1, framebuffers);
return framebuffers.get();
}
#Bridge
private static native void glShaderSource(int shader, int count, BytePtrPtr string, IntPtr length);
public static void glShaderSource(int shader, String code) {
glShaderSource(shader, 1, new BytePtrPtr().set(BytePtr.toBytePtrAsciiZ(code)), null);
}
#Bridge
private static native void glGetShaderInfoLog(int shader, int maxLength, IntPtr length, BytePtr infoLog);
public static String glGetShaderInfoLog(int shader) {
BytePtr infoLog = INFO_LOG.get();
glGetShaderInfoLog(shader, MAX_INFO_LOG_LENGTH, null, infoLog);
return infoLog.toStringAsciiZ();
}
#Bridge
public static native void glGetShaderPrecisionFormat(int shaderType, int precisionType, IntBuffer range, IntBuffer precision);
#Bridge
public static native void glTexImage2D(int target, int level, int internalformat, int width, int height, int border, int format, int type, IntBuffer data);
#Bridge
private static native void glVertexAttribPointer(int index, int size, int type, int normalized, int stride, Buffer pointer);
public static void glVertexAttribPointer(int index, int size, int type, boolean normalized, int stride, Buffer pointer) {
glVertexAttribPointer(index, size, type, normalized ? GL_TRUE : GL_FALSE, stride, pointer);
}
}
Note how most methods are exposed via just trivial #Bridge-annotated native definitions, but for some it's convenient to define a wrapper method in Java that converts a String to a *char or unpacks a result from an IntPtr for example.
I didn't post my whole library file, since it is still very incomplete and it'll just make it harder to find the examples of how different parameter types are handled.
To save yourself some work, you can copy the GL constant definitions from libGDX's GL20.java. And the OpenGL ES docs are a great reference for the calling signature of the methods (the data types GLenum and GLbitfield correspond to a Java int).
You can then call the gl-methods statically by prepending GLES20. (just like on Android), e.g.:
GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);
Turns out Bro is so smart that you don't even need to include the <framework>OpenGLES</framework> tag in robovm.xml any more, like you would with libGDX.
And - What do you know? - my app starts about 3 times as quickly as it did when it was still using libGDX. And it fixed another issue I had (see LibGDX displays black screen while app is paused but still visible (e.g. during in-app purchase password dialog) on iOS). "Yay!" for getting rid of unnecessary baggage.
The one thing that makes life a little annoying is that if you mess up the call signature of a method or the memory allocation, your app will simply crash with a very unhelpful "Terminated due to signal 11" message in the IDE-console that contains no information about where the app died.
SCNetworkReachabilityCallBack has a C pointer to a user-specified info. Does that info guarantee to point to the same context object that was passed in SCNetworkReachabilitySetCallback's context parameter?
Boolean SCNetworkReachabilitySetCallback (
SCNetworkReachabilityRef target,
SCNetworkReachabilityCallBack callout,
SCNetworkReachabilityContext *context
);
typedef void (*SCNetworkReachabilityCallBack) (
SCNetworkReachabilityRef target,
SCNetworkReachabilityFlags flags,
void *info
);
SCNetwortReachability reference
It points to the info field of the context structure that you associated with that particular SCNetworkReachabilityRef.
typedef struct {
CFIndex version;
void * info;
const void *(*retain)(const void *info);
void (*release)(const void *info);
CFStringRef (*copyDescription)(const void *info);
} SCNetworkReachabilityContext;
public interface Kernel32 extends StdCallLibrary {
int GetComputerNameW(Memory lpBuffer, IntByReference lpnSize);
}
public class Kernel32Test {
private static final String THIS_PC_NAME = "tiangao-160";
private static Kernel32 kernel32;
#BeforeClass
public static void setUp() {
System.setProperty("jna.encoding", "GBK");
kernel32 = (Kernel32) Native.loadLibrary("kernel32", Kernel32.class);
}
#AfterClass
public static void tearDown() {
System.setProperty("jna.encoding", null);
}
#Test
public void testGetComputerNameW() {
final Memory lpBuffer = new Memory(1024);
final IntByReference lpnSize = new IntByReference();
final int result = kernel32.GetComputerNameW(lpBuffer, lpnSize);
if (result != 0) {
throw new IllegalStateException(
"calling 'GetComputerNameW(lpBuffer, lpnSize)'failed，errorcode：" + result);
}
final int bufferSize = lpnSize.getValue();
System.out.println("value of 'lpnSize'：" + bufferSize);
Assert.assertEquals(THIS_PC_NAME.getBytes().length + 1, bufferSize);
final String name = lpBuffer.getString(0);
System.out.println("value of 'lpBuffer'：" + name);
Assert.assertEquals(THIS_PC_NAME, name);
}
}
The offical instructions says use byte[]、char[]、Memory or NIO Buffer for mapping char pointer in c native function.But I tried all of above, and String、WString、StringArrays、class extends PointType etc, all of them are no use.
Out parameter 'lpnSize' can return the corret buffer size，but 'lpBuffer' return 'x>'(i think it's random memory) or nothing no matter I mapping any java type.If i wrote someting to the 'lpBuffer' memory first, it would read the same things after calling native function.
How can I solve the problem?
You need to use Pointer.getString(0, true) to extract the unicode string returned by GetComputerNameW.
EDIT
You'll also need to call GetComputerNameW again with the length parameter initialized before the function will fill in the result. Either pass back the same IntByReference to a second call, or initialize the IntByReference to the size of your Memory buffer to have the buffer written to in the first call.
I have the following C code that uses libmodbus to read a single device register using ModbusTCP:
modbus_t *ctx;
uint16_t tab_reg[16];
ctx = modbus_new_tcp("10.0.1.77", 502);
modbus_read_registers(ctx, 0x20, 2, tab_reg);
printf("reg = %d (0x%X)\n", tab_reg[0], tab_reg[0]);
printf("reg = %d (0x%X)\n", tab_reg[1], tab_reg[1]);
now trying to switch this over to Vala using a Vapi that I've generated, the contents of that for new and read are:
[CCode (cheader_filename = "modbus.h", cname = "modbus_new_tcp")]
public static unowned Modbus.modbus_t create_tcp (string ip_address, int port);
public static int read_registers (Modbus.modbus_t ctx, int addr, int nb, uint16 dest);
[CCode (cheader_filename = "modbus.h")]
and the translated Vala program is:
class ModbusReadTest : GLib.Object {
unowned Modbus.modbus_t ctx;
public void run () {
uint16 reg = 0x00;
ctx = create_tcp ("10.0.1.77", 502);
Modbus.read_registers (ctx, 0x20, 2, reg);
message ("reg = %d (0x%X)", reg, reg);
Modbus.close(ctx);
}
}
Coincidentally, when I compile this into C code and then into a binary using gcc I get the error:
read-registers-test.c:71:2: warning: passing argument 4 of ‘modbus_read_registers’ makes pointer from integer without a cast [enabled by default]
which is not surprising. But I'm not sure how I should go about modifying the Vapi contents to closer match the prototype in the libmodbus header:
int modbus_read_registers(modbus_t *ctx, int addr, int nb, uint16_t *dest);
I've tried a mix of array options and using 'out', but haven't been able to get more than a single double byte register at a time.
read_registers should probably be an instance method (on Modbus.modbus_t) instead of a static method, and Modbus.modbus_t should probably be renamed to something like Modbus.Context, create_tcp should probably be a constructor, and Modbus.close should be a free function on the Modbus.Context compact class, but that's beside the point of this question (if you stop by #vala on irc.gnome.org you can get help with that stuff).
You probably want to make it an array:
public static int read_registers (Modbus.modbus_t ctx, int addr, [CCode (array_length_pos = 2.5)] uint16[] dest);
Then you would do something like this in Vala:
public void run () {
uint16 reg[2];
ctx = create_tcp ("10.0.1.77", 502);
Modbus.read_registers (ctx, 0x20, reg);
message ("reg = %d (0x%X)", reg, reg);
Modbus.close(ctx);
}
For a port more faithful to the original C (where tab_reg has 16 elements instead of 2), you could use array slicing:
public void run () {
uint16 reg[16];
ctx = create_tcp ("10.0.1.77", 502);
Modbus.read_registers (ctx, 0x20, reg[0:2]);
stdout.printf ("reg = %d (0x%X)\n", reg, reg);
Modbus.close(ctx);
}
Note that if you make it an instance method you'll need to change the array_length_pos to 1.5.
I'm trying to print XPS documents from a windows service on the .net framework. Since Microsoft does not support printing by using System.Drawing.Printing nor by using System.Printing (WPF), I'm using the native XPSPrint API.
This is suggested to me by Aspose in http://www.aspose.com/documentation/.net-components/aspose.words-for-.net/howto-print-a-document-on-a-server-via-the-xpsprint-api.html.
When I try to print an XPS document from a windows service, the result contains strange characters instead of the text I want.
I tried with different printers (including virtual printers like for instance PDFCreator), different users and user-privileges for the service, different xps generators (aspose, word 2007, word 2010), different platforms (windows 7, windows 2008 R2) but all have the same result.
Does anybody knows how to solve this? Any help would be appreciated!
For those who want to try it, I shared some files via:
https://docs.google.com/leaf?id=0B4J93Ly5WzQKNWU2ZjM0MDYtMjFiMi00NzM0LTg4MTgtYjVlNDA5NWQyMTc3&hl=nl
document.xps: the XPS document to print
document_printed_to_pdfcreator.pdf: the printed document that demonstrates what is going wrong
XpsPrintTest.zip: a sample VS2010 solution with the sample code
The sample code for the managed windows service is:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Linq;
using System.ServiceProcess;
using System.Text;
using System.IO;
using System.Threading;
using System.Runtime.InteropServices;
namespace PrintXpsService
{
public partial class XpsPrintService : ServiceBase
{
// Change name of printer here
private String f_printerName = "PDFCreator";
// path to some file where logging is done
private String f_logFile = #"C:\temp\testdoc\xps_printing_service_log.txt";
// path to xps file to print
private String f_xpsFile = #"C:\temp\testdoc\document.xps";
public XpsPrintService()
{
InitializeComponent();
}
private void Log(String fmt, params Object[] args)
{
try
{
DateTime now = DateTime.Now;
using (StreamWriter wrt = new StreamWriter(f_logFile, true))
{
wrt.Write("{0} {1} - ", now.ToShortDateString(), now.ToShortTimeString());
wrt.WriteLine(fmt, args);
}
}
catch (Exception ex)
{
}
}
protected override void OnStart(string[] args)
{
// uncomment to allow to connect debugger
//int i = 0;
//while (i == 0)
//{
// if (i == 0)
// {
// Thread.Sleep(1000);
// }
//}
Log("Starting Service");
try
{
Log("Printing xps file {0}", f_xpsFile);
using (Stream stream = new FileStream(f_xpsFile, FileMode.Open, FileAccess.Read))
{
Log("Starting to print on printer {0}", f_printerName);
String jobName = f_xpsFile;
this.Print(stream, jobName);
}
Log("Document printed");
}
catch (Exception ex)
{
Log("Exception during execution: {0}", ex.Message);
Log(" {0}", ex.StackTrace);
Exception inner = ex.InnerException;
while (inner != null)
{
Log("=== Inner Exception: {0}", inner.Message);
Log(" {0}", inner.StackTrace);
inner = inner.InnerException;
}
}
}
protected override void OnStop()
{
}
public void Print(Stream stream, String jobName)
{
String printerName = f_printerName;
IntPtr completionEvent = CreateEvent(IntPtr.Zero, true, false, null);
try
{
IXpsPrintJob job;
IXpsPrintJobStream jobStream;
StartJob(printerName, jobName, completionEvent, out job, out jobStream);
CopyJob(stream, job, jobStream);
WaitForJob(completionEvent, -1);
CheckJobStatus(job);
}
finally
{
if (completionEvent != IntPtr.Zero)
CloseHandle(completionEvent);
}
}
private void StartJob(String printerName,
String jobName, IntPtr completionEvent,
out IXpsPrintJob job,
out IXpsPrintJobStream jobStream)
{
int result = StartXpsPrintJob(printerName, jobName, null, IntPtr.Zero, completionEvent,
null, 0, out job, out jobStream, IntPtr.Zero);
if (result != 0)
throw new Win32Exception(result);
}
private void CopyJob(Stream stream, IXpsPrintJob job, IXpsPrintJobStream jobStream)
{
try
{
byte[] buff = new byte[4096];
while (true)
{
uint read = (uint)stream.Read(buff, 0, buff.Length);
if (read == 0)
break;
uint written;
jobStream.Write(buff, read, out written);
if (read != written)
throw new Exception("Failed to copy data to the print job stream.");
}
// Indicate that the entire document has been copied.
jobStream.Close();
}
catch (Exception)
{
// Cancel the job if we had any trouble submitting it.
job.Cancel();
throw;
}
}
private void WaitForJob(IntPtr completionEvent, int timeout)
{
if (timeout < 0)
timeout = -1;
switch (WaitForSingleObject(completionEvent, timeout))
{
case WAIT_RESULT.WAIT_OBJECT_0:
// Expected result, do nothing.
break;
case WAIT_RESULT.WAIT_TIMEOUT:
// timeout expired
throw new Exception("Timeout expired");
case WAIT_RESULT.WAIT_FAILED:
throw new Exception("Wait for the job to complete failed");
default:
throw new Exception("Unexpected result when waiting for the print job.");
}
}
private void CheckJobStatus(IXpsPrintJob job)
{
XPS_JOB_STATUS jobStatus;
job.GetJobStatus(out jobStatus);
switch (jobStatus.completion)
{
case XPS_JOB_COMPLETION.XPS_JOB_COMPLETED:
// Expected result, do nothing.
break;
case XPS_JOB_COMPLETION.XPS_JOB_IN_PROGRESS:
// expected, do nothing, can occur when printer is paused
break;
case XPS_JOB_COMPLETION.XPS_JOB_FAILED:
throw new Win32Exception(jobStatus.jobStatus);
default:
throw new Exception("Unexpected print job status.");
}
}
[DllImport("XpsPrint.dll", EntryPoint = "StartXpsPrintJob")]
private static extern int StartXpsPrintJob(
[MarshalAs(UnmanagedType.LPWStr)] String printerName,
[MarshalAs(UnmanagedType.LPWStr)] String jobName,
[MarshalAs(UnmanagedType.LPWStr)] String outputFileName,
IntPtr progressEvent, // HANDLE
IntPtr completionEvent, // HANDLE
[MarshalAs(UnmanagedType.LPArray)] byte[] printablePagesOn,
UInt32 printablePagesOnCount,
out IXpsPrintJob xpsPrintJob,
out IXpsPrintJobStream documentStream,
IntPtr printTicketStream); // This is actually "out IXpsPrintJobStream", but we don't use it and just want to pass null, hence IntPtr.
[DllImport("Kernel32.dll", SetLastError = true)]
private static extern IntPtr CreateEvent(IntPtr lpEventAttributes, bool bManualReset, bool bInitialState, string lpName);
[DllImport("Kernel32.dll", SetLastError = true, ExactSpelling = true)]
private static extern WAIT_RESULT WaitForSingleObject(IntPtr handle, Int32 milliseconds);
[DllImport("Kernel32.dll", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
private static extern bool CloseHandle(IntPtr hObject);
}
/// <summary>
/// This interface definition is HACKED.
///
/// It appears that the IID for IXpsPrintJobStream specified in XpsPrint.h as
/// MIDL_INTERFACE("7a77dc5f-45d6-4dff-9307-d8cb846347ca") is not correct and the RCW cannot return it.
/// But the returned object returns the parent ISequentialStream inteface successfully.
///
/// So the hack is that we obtain the ISequentialStream interface but work with it as
/// with the IXpsPrintJobStream interface.
/// </summary>
[Guid("0C733A30-2A1C-11CE-ADE5-00AA0044773D")] // This is IID of ISequenatialSteam.
[InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
interface IXpsPrintJobStream
{
// ISequentualStream methods.
void Read([MarshalAs(UnmanagedType.LPArray)] byte[] pv, uint cb, out uint pcbRead);
void Write([MarshalAs(UnmanagedType.LPArray)] byte[] pv, uint cb, out uint pcbWritten);
// IXpsPrintJobStream methods.
void Close();
}
[Guid("5ab89b06-8194-425f-ab3b-d7a96e350161")]
[InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
interface IXpsPrintJob
{
void Cancel();
void GetJobStatus(out XPS_JOB_STATUS jobStatus);
}
[StructLayout(LayoutKind.Sequential)]
struct XPS_JOB_STATUS
{
public UInt32 jobId;
public Int32 currentDocument;
public Int32 currentPage;
public Int32 currentPageTotal;
public XPS_JOB_COMPLETION completion;
public Int32 jobStatus; // UInt32
};
enum XPS_JOB_COMPLETION
{
XPS_JOB_IN_PROGRESS = 0,
XPS_JOB_COMPLETED = 1,
XPS_JOB_CANCELLED = 2,
XPS_JOB_FAILED = 3
}
enum WAIT_RESULT
{
WAIT_OBJECT_0 = 0,
WAIT_ABANDONED = 0x80,
WAIT_TIMEOUT = 0x102,
WAIT_FAILED = -1 // 0xFFFFFFFF
}
}
Note: some links for more information:
MS not supporting printing from managed code: http://support.microsoft.com/kb/324565 , http://msdn.microsoft.com/en-us/library/system.drawing.printing.aspx and http://msdn.microsoft.com/en-us/library/bb613549.aspx
XPSPrint API: http://msdn.microsoft.com/en-us/library/dd374565(VS.85).aspx
I talked with microsoft about this issue and we discovered the problem is related to incorrect font substitution in the printer-spooler. When the printer is set to not spool the documents, they are printed correctly, also from a windows service. Otherwise, all fonts, except arial (and maybe some others), are substituted by another font. In the sample I provided, calibri is substituted by wingdings.
So, they acknowledge this to be a bug but at the moment they will not resolve it. It will depend on how many people will suffer from this bug in order for them to decide whether are not they are willing to fix it...