How one can obtain path to module?
I am writing extension enclosed in a DLL and want to get path to my library in runtime.
Update
Of course first way worked fine
static wxString GetModulePath()
{
static wxString path;
WCHAR buf[512] = {0};
GetModuleFileName(NULL, buf, 511);
path = buf;
return wxPathOnly(path);
}
but finally I ended with second one
wxStandardPaths sp;
wxLogError(sp.GetPluginsDir());
Have a look at the wxStandardPaths class. For your problem its GetExecutablePath() or GetPluginsDir() methods could be used - I'm just not sure what you want to do.
I used
#include "wx/stdpaths.h"
#include "dialogsApp.h"
#include "dialogsMain.h"
IMPLEMENT_APP(dialogsApp);
bool dialogsApp::OnInit()
{
wxString xpath;
xpath = wxStandardPaths::Get().GetExecutablePath();
That seems to work.
This isn't wxWidgets specific. Windows has a function called GetModuleFileName that does what you want. The link is to the msdn page.
Related
The wxPuts method used in this tutorial (http://zetcode.com/gui/wxwidgets/helperclasses/) doesn't work. Was it changed and the class is no longer available?
I tried searching online for some documentation about wxPuts and wxPrintf, but can't find anything relevant in the helper files in the wxWidg site.
#include <wx/textfile.h>
int main(int argc, char **argv)
{
wxTextFile file(wxT("test.c"));
file.Open();
wxPrintf(wxT("Number of lines: %d\n"), file.GetLineCount());
wxPrintf(wxT("First line: %s\n"), file.GetFirstLine().c_str());
wxPrintf(wxT("Last line: %s\n"), file.GetLastLine().c_str());
wxPuts(wxT("-------------------------------------"));
wxString s;
for ( s = file.GetFirstLine(); !file.Eof();
s = file.GetNextLine() )
{
wxPuts(s);
}
file.Close();
}
wxWidgets provides wrappers for all standard CRT functions working with strings in order to allow calling them with wxString or wchar_t (wide) strings. These wrappers are not documented because it doesn't make much sense to re-document the standard functions, but basically for any foo(const char* s) in the standard library, you have wxFoo(const wxString& s) declared in wx/crt.h header. You have to include this header to get these declarations, however.
Also note that most of wxWidgets functionality can't be used before the library is initialized.
TL;DR: you're missing #include <wx/crt.h>.
I am currently trying to build the mosquitto-auth-plugin on windows but I am unsure which make process to use. The doc says to edit the config.mk file which I have done, then to 'make' the auth-plug -- this is were I am struck I have tried to make using GnWin & MinGW but neither has worked is there a way to build-make the library on windows or can I make it in Linux and copy the auth-plug.o to my windows machine?
I'm not aware of anybody having attempted to build mosquitto-auth-plug on Windows, and I'd be very surprised if that worked at all; as the author of the plugin, I paid no attention to portability outside Un*x, and so as to not raise hopes, I will not. :-)
That said, you cannot run (load) shared objects built on Linux on Windows. What may be possible, but it's been years since I did anything similar, is to cross compile with an appropriate toolchain.
I build it for Windows, using the HTTP and JWT backends only.
Had to fix:
Put __declspec(dllexport) to the mosquitto_auth_Xyz... functions in auth-plug.c.
Added alternative code for fnmatch(a,b) and strsep() in auth-plug.c, see below.
In log.c I fell back to use log=__log instead of log=mosquitto_log_printf as I failed importing the function from libmosquitto.
Compiled using Visual Studio 2017 Express with preprocessor definitions _CRT_NONSTDC_NO_DEPRECATE and _CRT_SECURE_NO_WARNINGS put into place.
The code works fine!
For fnmatch(a,b) and strsep() in auth-plug.c change the #include to:
#ifdef _WIN32
#include <windows.h>
#include <shlwapi.h>
#define fnmatch(a, b, c) PathMatchSpecA(a, b)
extern char* strsep(char** stringp, const char* delim)
{
char* start = *stringp;
char* p;
p = (start != NULL) ? strpbrk(start, delim) : NULL;
if (p == NULL)
{
*stringp = NULL;
}
else
{
*p = '\0';
*stringp = p + 1;
}
return start;
}
#else
#include <fnmatch.h>
#endif
I have created a GUI using tcl. I want to make some of the core functionalities of the tcl code available to be used by any program which supports dll. For that i have taken a very simple tcl code example, which adds two integer numbers and i have written a c wrapper function to use this functionality. This is working for me. Now how can i create a dll for these two c and tcl files, so that any program can use this addition functionality by simply loading the dll.
Here is my simple tcl code :
/* Filename : simple_addition.tcl */
#!/usr/bin/env tclsh8.5
proc add_two_nos { } {
set a 10
set b 20
set c [expr { $a + $b } ]
puts " c is $c ......."
}
And here is my c wrapper function which uses the above tcl addition functionality :
#include <tcl.h>
#include <tclDecls.h>
#include <tclPlatDecls.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int main (int argc, char **argv) {
Tcl_Interp *interp;
int code;
char *result;
printf("inside main function \n");
Tcl_FindExecutable(argv[0]);
interp = Tcl_CreateInterp();
code = Tcl_Eval(interp, "source simple_addition.tcl; add_two_nos");
/* Retrieve the result... */
result = Tcl_GetString(Tcl_GetObjResult(interp));
/* Check for error! If an error, message is result. */
if (code == TCL_ERROR) {
fprintf(stderr, "ERROR in script: %s\n", result);
exit(1);
}
/* Print (normal) result if non-empty; we'll skip handling encodings for now */
if (strlen(result)) {
printf("%s\n", result);
}
/* Clean up */
Tcl_DeleteInterp(interp);
exit(0);
}
This c wrapper is working fine for me and gives correct results.
Now I want to create a dll file, so that if i include that dll to any program that supports dll, it should be able to use this addition functionality of the above tcl code. Can anybody please tell me the way i can do it. Please help me. I am new to this dll concept.
In order to create the .dll you'll have to use something like Visual Studio and C or C++ to create the .dll (there are lots of other tools out there that can create .dll files but VS is easy to get hold of and to use.) So in VS create a new project, this needs to be a C++ WIN32 project. Select the DLL application type and the Export Symbols additional option.
VS will create a basic .dll that you can then amend to do what you want. I short I'd look at putting the creating/destruction of the intrepter into the dllmain:
BOOL APIENTRY DllMain( HMODULE hModule,
DWORD ul_reason_for_call,
LPVOID lpReserved
)
{
switch (ul_reason_for_call)
{
case DLL_PROCESS_ATTACH:
{
Tcl_FindExecutable(NULL);
interp = Tcl_CreateInterp();
}
case DLL_THREAD_ATTACH:
break ;
case DLL_THREAD_DETACH:
break ;
case DLL_PROCESS_DETACH:
{
Tcl_DeleteInterp(interp);
break;
}
}
return TRUE;
}
and then create functions exported by the .dll that make use of the interpreter. If you aren't familiar with the concept of shared libaries then I'd suggest spending a little time reading up on them, try here and here for some background reading.
I'm developing an app in C++/CLI and have a csv file writing library in unmanaged code that I want to use from the managed portion. So my function looks something like this:
bool CSVWriter::Write(const char* stringToWrite);
...but I'm really struggling to convert my shiny System::String^ into something compatible. Basically I was hoping to call by doing something like:
if( m_myWriter->Write(String::Format("{0}",someValueIWantToSave)) )
{
// report success
}
using namespace System::Runtime::InteropServices;
const char* str = (const char*) (Marshal::StringToHGlobalAnsi(managedString)).ToPointer();
From Dev Shed.
As mcandre mentions, Marshal::StringToHGlobalAnsi() is correct. But don't forget to free the newly allocated resource with Marshal::FreeHGlobal(), when the string is no longer in use.
Alternatively, you can use the msclr::interop::marshal_as template to create the string resource and automatically release it when the call exits the resource's scope.
There's a list of what types need which conversion in the overview of marshalling in C++.
The offsetof macro seems not to work under C++/CLI.
This works fine in unmanaged C++, but throws "error C2275: 'Entity' :illegal use of this type as an expression" error in CLI.
struct Property{
char* label;
PropertyTypes type;
unsigned int member_offset;
unsigned int position;
unsigned char bit_offset;
};
struct Entity{
...
bool transparent;
...
};
Property property = {"Transparent",
TYPE_BOOL,
offsetof(Entity, transparent),
0,
0}; // C2275 HERE
Does CLI have some replacement?
My guess would be that the compiler message boils down to: "offsetof" is not a known macro and if it was a function its parameters must not contain a typename.
Edit: As somebody pointed out in the comments, offsetof is actually part of the std lib. So what's missing is probably just
#include <cstddef>
Alternatively, you can use this macro implementation (taken from Win32/MFC headers):
#ifdef _WIN64
#define OFFSET_OF( s, m )\
(size_t)((ptrdiff_t)&reinterpret_cast<const volatile char&>((((s*)0)->m)) )
#else
#define OFFSET_OF( s, m )\
(size_t)&reinterpret_cast<const volatile char&>((((s*)0)->m))
#endif
Standard C++ already has an alternative; &Entity::transparent. You'll probably want to use templates when redesigning the Propery class. The type of a pointer-to-member is non-trivial.
You will need to provide the type of the object you are assigning to. Looks like there is some type-mismatch for the member in question.
See this for sample usage.
Just a shot in the dark and without a chance to double-check this - should
offsetof(Entity, transparent),
perhaps rather read
offsetof( struct Entity, transparent ),
???