If I put the WNDCLASSEX wcex variable definition out of main function (as global variable) the class will be registered successfully
#include <windows.h>
WNDCLASSEX wcex;
int main()
{
wcex.cbSize = sizeof ( WNDCLASSEX );
wcex.lpszClassName = "Success" ;
if ( !RegisterClassEx ( &wcex ) )
{
MessageBox ( NULL, "Failed to register window class.", "Error", MB_OK );
}
}
But If I put it inside the main function, It will not be registered
#include <windows.h>
int main()
{
WNDCLASSEX wcex;
wcex.cbSize = sizeof ( WNDCLASSEX );
wcex.lpszClassName = "Success" ;
if ( !RegisterClassEx ( &wcex ) )
{
MessageBox ( NULL, "Failed to register window class.", "Error", MB_OK );
}
}
I can't figure out the reason, kindly help in this issue.
Thanks in advance.
Objects with static storage duration are zero-initialized1). Your second example is semantically different in that wcex (automatic storage duration) holds random values. To match the semantics, use WNDCLASSEX wcex = { 0 }; instead.
1) Assuming you are using a C++ compiler. The rules for C are different.
Related
OK. Looked at the various answers when I typed out the question, and don't see the answer listed.
This seems such a basic, fundamental issue that I MUST be doing something wrong, but I am being driven crazy (actually, not much of a "drive." More of a short putt) trying to figure out what I am getting wrong.
I have created a test project that can be downloaded here (small project).
In any case, I encountered this, when working on importing a large Objective-C SDK that I wrote into Swift.
Everything works great. Until... I try to do comparisons on enums declared in C.
Obviously, C enums are not turned into Swift enums, but I am having trouble figuring out how to use them.
Here's a sample of what you will see in the test project;
I have a couple of C files that declare enums:
#import <Foundation/Foundation.h>
typedef enum
{
StandardEnumType_Undef = 0xFF,
StandardEnumType_Value0 = 0x00,
StandardEnumType_Value1 = 0x01,
StandardEnumType_Value2 = 0x02
} StandardEnumType;
typedef NS_ENUM ( unsigned char, AppleEnumType )
{
AppleEnumType_Undef = 0xFF,
AppleEnumType_Value0 = 0x00,
AppleEnumType_Value1 = 0x01,
AppleEnumType_Value2 = 0x02
};
StandardEnumType translateIntToEnumValue ( int inIntValue );
int translateEnumValueToInt ( StandardEnumType inValue );
AppleEnumType translateIntToAppleEnumValue ( int inIntValue );
int translateAppleEnumValueToInt ( AppleEnumType inValue );
The functions mentioned do pretty much what it says on the tin. I won't include them.
I did the bridging header and all that.
I am trying to use them in the initial load of the Swift app:
func application(application: UIApplication!, didFinishLaunchingWithOptions launchOptions: NSDictionary!) -> Bool
{
let testStandardConst:StandardEnumType = translateIntToEnumValue ( 0 )
// Nope.
// if ( testStandardConst.toRaw() == 0 )
// {
//
// }
// This don't work.
// if ( testStandardConst == StandardEnumType_Value0 )
// {
//
// }
// Neither does this.
// if ( testStandardConst == StandardEnumType_Value0.toRaw() )
// {
//
// }
// Not this one, either.
// if ( testStandardConst.toRaw() == StandardEnumType_Value0 )
// {
//
// }
let testAppleConst:AppleEnumType = translateIntToAppleEnumValue ( 0 )
// This don't work.
// if ( testAppleConst == AppleEnumType.AppleEnumType_Value0 )
// {
//
// }
// Neither does this.
// if ( testAppleConst == AppleEnumType.AppleEnumType_Value0.toRaw() )
// {
//
// }
// Nor this.
// if ( testAppleConst == .AppleEnumType_Value0 )
// {
//
// }
return true
}
I can't seem to get the $##!! enums to compare to either ints or anything else.
I am often humbled by the stupid errors I make, and sometimes need them pointed out to me, so please humble me.
Thanks!
When working with typedef NS_ENUM enums in swift you should omit enum name in comparison and assignment, here how you can compare it:
if ( testAppleConst == .Value0 ) { ... }
You can read more about this in Apple do s for Swift here.
i am new to spider monkey and want to use it for transform java script file to sequence of byte code.
i get spider monkey and build it in debug mode.
i want to use JS_CompileScript function in jsapi.h to compile javascript code and analysis this to get bytecode , but when in compile below code and run it , i get run time error.
the error is "Unhandled exception at 0x0f55c020 (mozjs185-1.0.dll) in spiderMonkeyTest.exe: 0xC0000005: Access violation reading location 0x00000d4c." and i do not resolve it.
any body can help me to resolve this or introducing other solutions to get byte code from javascript code by using spider monkey ?
// spiderMonkeyTest.cpp : Defines the entry point for the console application.
//
#define XP_WIN
#include <iostream>
#include <fstream>
#include "stdafx.h"
#include "jsapi.h"
#include "jsanalyze.h"
using namespace std;
using namespace js;
static JSClass global_class = { "global",
JSCLASS_NEW_RESOLVE | JSCLASS_GLOBAL_FLAGS,
JS_PropertyStub,
NULL,
JS_PropertyStub,
JS_StrictPropertyStub,
JS_EnumerateStub,
JS_ResolveStub,
JS_ConvertStub,
NULL,
JSCLASS_NO_OPTIONAL_MEMBERS
};
int _tmain(int argc, _TCHAR* argv[]) {
/* Create a JS runtime. */
JSRuntime *rt = JS_NewRuntime(16L * 1024L * 1024L);
if (rt == NULL)
return 1;
/* Create a context. */
JSContext *cx = JS_NewContext(rt, 8192);
if (cx == NULL)
return 1;
JS_SetOptions(cx, JSOPTION_VAROBJFIX);
JSScript *script;
JSObject *obj;
const char *js = "function a() { var tmp; tmp = 1 + 2; temp = temp * 2; alert(tmp); return 1; }";
obj = JS_CompileScript(cx,JS_GetGlobalObject(cx),js,strlen(js),"code.js",NULL);
script = obj->getScript();
if (script == NULL)
return JS_FALSE; /* compilation error */
js::analyze::Script *sc = new js::analyze::Script();
sc->analyze(cx,script);
JS_DestroyContext(cx);
JS_DestroyRuntime(rt);
/* Shut down the JS engine. */
JS_ShutDown();
return 1;
}
Which version of Spidermonkey are you using? I am using the one that comes with FireFox 10 so the API may be different.
You should create a new global object and initialize it by calling JS_NewCompartmentAndGlobalObject() and JS_InitStandardClasses() before compiling your script :
.....
/*
* Create the global object in a new compartment.
* You always need a global object per context.
*/
global = JS_NewCompartmentAndGlobalObject(cx, &global_class, NULL);
if (global == NULL)
return 1;
/*
* Populate the global object with the standard JavaScript
* function and object classes, such as Object, Array, Date.
*/
if (!JS_InitStandardClasses(cx, global))
return 1;
......
Note, the function JS_NewCompartmentAndGlobalObject() is obsolete now, check the latest JSAPI documentation for the version your are using. Your JS_CompileScript() call just try to retrieve a global object which has not been created and probably this causes the exception.
how about using function "SaveCompiled" ? it will save object/op-code (compiled javascript) to file
I want to use the GSL for integration
http://www.gnu.org/software/gsl/manual/html_node/Numerical-Integration.html
However, I find no convenient way how the integrated function
(the function f in the example http://www.gnu.org/software/gsl/manual/html_node/Numerical-integration-examples.html)
can report an error to the integrator. I want to integrate a function which itself results from an integration that could fail. This is my sample program
#include <stdio.h>
#include <math.h>
#include <gsl/gsl_integration.h>
#include <gsl/gsl_errno.h>
double f (double x, void * params) {
GSL_ERROR("test error",GSL_FAILURE);
return 0.0;
}
int main (void)
{
gsl_integration_workspace * w = gsl_integration_workspace_alloc (1000);
double result, error;
gsl_function F;
F.function = &f;
gsl_set_error_handler_off();
int status = gsl_integration_qags (&F, 0, 1, 0, 1e-7, 1000,
w, &result, &error);
printf ("status = %d\n", status);
status = GSL_FAILURE;
printf ("status = %d\n", status);
gsl_integration_workspace_free (w);
return 0;
}
resulting in the output
status = 0
status = -1
I think the integrator should rather stop and return my error code. How can I achieve this?
Thank you very much for your help!!!
2011-04-27: I also tried this variant, after Brian Gough told me,
#include <stdio.h>
#include <math.h>
#include <gsl/gsl_integration.h>
#include <gsl/gsl_errno.h>
double f (double x, void * params) {
GSL_ERROR("test error",GSL_FAILURE);
return GSL_NAN;
}
int main (void)
{
gsl_integration_workspace * w = gsl_integration_workspace_alloc (1000);
double result, error;
gsl_function F;
F.function = &f;
gsl_set_error_handler_off();
int status = gsl_integration_qags (&F, 0, 1, 0, 1e-7, 1000,
w, &result, &error);
printf ("status = %d\n", status);
status = GSL_FAILURE;
printf ("status = %d\n", status);
gsl_integration_workspace_free (w);
return 0;
}
it did not help either. I will now fill out a bug report.
Thanks to Xuebin Wu from the GSL Mailing list the problem is solved:
Hi,
GSL_ERROR itself is a macro, it looks like
gsl_error (reason, __FILE__, __LINE__, gsl_errno);
return gsl_errno;
The function already returns before you return NAN, because GSL_ERROR
has been called. Turning the handler off just let the first line do
nothing. The default error handler abort the program after printing
error message.
I do not think it is a bug. Maybe you can write your own error handler
to solve your problem. For example, you can use "goto" to jump out of
gsl_integration_qags, or set some global variable to indicate the
integration result is incorrect.
PS: I believe this macro is what you need,
Macro: GSL_ERROR_VAL (reason, gsl_errno, value)
This macro is the same as GSL_ERROR but returns a user-defined value
of value instead of an error code. It can be used for mathematical
functions that return a floating point value.
The following example shows how to return a NaN at a mathematical
singularity using the GSL_ERROR_VAL macro,
if (x == 0)
{
GSL_ERROR_VAL("argument lies on singularity",
GSL_ERANGE, GSL_NAN);
}
So I adjusted the code according to
#include <stdio.h>
#include <math.h>
#include <gsl/gsl_integration.h>
#include <gsl/gsl_errno.h>
double f (double x, void * params) {
// return GSL_NAN;
GSL_ERROR_VAL ("argument lies on singularity", GSL_ERANGE, GSL_NAN);
}
int main (void)
{
gsl_integration_workspace * w = gsl_integration_workspace_alloc (1000);
double result, error;
gsl_function F;
F.function = &f;
gsl_set_error_handler_off();
int status = gsl_integration_qags (&F, 0, 1, 0, 1e-7, 1000,
w, &result, &error);
printf ("status = %d\n", status);
status = GSL_FAILURE;
printf ("status = %d\n", status);
gsl_integration_workspace_free (w);
return 0;
}
and everything works as expected...
A bit hackish, but I'd probably have your function store some flag. When it encounters an error it sets the flag and returns zero for all subsequent evaluations. Then, after you've integrated it you can check this flag to see if the result is valid.
What about to write a wrapper for the function which returns pointer to a structure, containing function results and error status ? Or if you use c++, this encapsulation can be made with use of objects ....
In my setup.dll i have the folowing:
#include "stdafx.h"
#include "ce_setup.h"
TCHAR Message[] = _T("TERMS & CONDITIONS\r\n ")
_T("Do you agree to terms? \r\n");
codeINSTALL_INIT Install_Init
(
HWND hwndParent,
BOOL fFirstCall,
BOOL fPreviouslyInstalled,
LPCTSTR pszInstallDir
)
{
if (!fFirstCall || ::MessageBoxW(0, Message, _T("RmapGeneric"), MB_YESNO) == IDYES)
return codeINSTALL_INIT_CONTINUE;
else
return codeINSTALL_INIT_CANCEL;
}
codeINSTALL_EXIT Install_Exit
(
HWND hwndParent,
LPCTSTR pszInstallDir,
WORD cFailedDirs,
WORD cFailedFiles,
WORD cFailedRegKeys,
WORD cFailedRegVals,
WORD cFailedShortcuts
)
{
PROCESS_INFORMATION pi = {0};
codeINSTALL_EXIT cie = codeINSTALL_EXIT_DONE;
TCHAR szPath[MAX_PATH];
_tcscpy(szPath, pszInstallDir);
_tcscat(szPath, _T("\\"));
_tcscat(szPath, _T("Application.exe"));
MessageBox(GetForegroundWindow(), szPath, L"status", MB_OK);
if (!CreateProcess(szPath, NULL, NULL, NULL, NULL, 0, NULL, NULL, NULL, &pi))
{
MessageBox(GetForegroundWindow(), szPath, L"failed", MB_OK);
cie = codeINSTALL_EXIT_UNINSTALL;
}
return cie;
}
While the first function works, the Install_Exit does not.
All i want is that after the installation the application automaticly starts.
Any suggestions what am i doing wrong?
There's nothing completely obvious as to what's wrong. Are you certain that the target executable is in that folder? Have you called GetLastError to see why it's failing?
Ok i found the problem in .DEF file
I forgot to export the exit function :S
I'm developing a COM dll which is an add-in to MSoffice. Since I'm not creating any logs within add-in I would like to add a crash report generator into my add-in.
Hopefully 'Minidump' would be the best choice, but I have never use Minidump inside a COM object.
I appreciate if somebody can point out possibilities of creating such crash dump with minidump
inside a COM object.
Thank You
I suspect you should be able to use the technique described here, create a minidump.
The actual implementation is
straightforward. The following is a
simple example of how to use
MiniDumpWriteDump.
#include <dbghelp.h>
#include <shellapi.h>
#include <shlobj.h>
int GenerateDump(EXCEPTION_POINTERS* pExceptionPointers)
{
BOOL bMiniDumpSuccessful;
WCHAR szPath[MAX_PATH];
WCHAR szFileName[MAX_PATH];
WCHAR* szAppName = L"AppName";
WCHAR* szVersion = L"v1.0";
DWORD dwBufferSize = MAX_PATH;
HANDLE hDumpFile;
SYSTEMTIME stLocalTime;
MINIDUMP_EXCEPTION_INFORMATION ExpParam;
GetLocalTime( &stLocalTime );
GetTempPath( dwBufferSize, szPath );
StringCchPrintf( szFileName, MAX_PATH, L"%s%s", szPath, szAppName );
CreateDirectory( szFileName, NULL );
StringCchPrintf( szFileName, MAX_PATH, L"%s%s\\%s-%04d%02d%02d-%02d%02d%02d-%ld-%ld.dmp",
szPath, szAppName, szVersion,
stLocalTime.wYear, stLocalTime.wMonth, stLocalTime.wDay,
stLocalTime.wHour, stLocalTime.wMinute, stLocalTime.wSecond,
GetCurrentProcessId(), GetCurrentThreadId());
hDumpFile = CreateFile(szFileName, GENERIC_READ|GENERIC_WRITE,
FILE_SHARE_WRITE|FILE_SHARE_READ, 0, CREATE_ALWAYS, 0, 0);
ExpParam.ThreadId = GetCurrentThreadId();
ExpParam.ExceptionPointers = pExceptionPointers;
ExpParam.ClientPointers = TRUE;
bMiniDumpSuccessful = MiniDumpWriteDump(GetCurrentProcess(), GetCurrentProcessId(),
hDumpFile, MiniDumpWithDataSegs, &ExpParam, NULL, NULL);
return EXCEPTION_EXECUTE_HANDLER;
}
void SomeFunction()
{
__try
{
int *pBadPtr = NULL;
*pBadPtr = 0;
}
__except(GenerateDump(GetExceptionInformation()))
{
}
}