Open CASCADE Technology  7.4.0
Static Public Member Functions

OSD Class Reference

Set of Operating Sytem Dependent (OSD) Tools. More...

#include <OSD.hxx>

Static Public Member Functions

static void SetSignal (OSD_SignalMode theSignalMode, Standard_Boolean theFloatingSignal)
 Sets or removes signal and FPE (floating-point exception) handlers. OCCT signal handlers translate signals raised by C subsystem to C++ exceptions inheriting Standard_Failure. More...
 
static void SetSignal (const Standard_Boolean theFloatingSignal=Standard_True)
 Sets signal and FPE handlers. Short-cut for OSD::SetSignal (OSD_SignalMode_Set, theFloatingSignal). More...
 
static void SetThreadLocalSignal (OSD_SignalMode theSignalMode, Standard_Boolean theFloatingSignal)
 Initializes thread-local signal handlers. This includes _set_se_translator() on Windows platform, and SetFloatingSignal(). The main purpose of this method is initializing handlers for newly created threads without overriding global handlers (set by application or by OSD::SetSignal()). More...
 
static void SetFloatingSignal (Standard_Boolean theFloatingSignal)
 Enables / disables generation of C signal on floating point exceptions (FPE). This call does NOT register a handler for signal raised in case of FPE - SetSignal() should be called beforehand for complete setup. Note that FPE setting is thread-local, new threads inherit it from parent. More...
 
static OSD_SignalMode SignalMode ()
 Returns signal mode set by the last call to SetSignal(). By default, returns OSD_SignalMode_AsIs. More...
 
static Standard_Boolean ToCatchFloatingSignals ()
 Returns true if floating point exceptions will raise C signal according to current (platform-dependent) settings in this thread. More...
 
static void SecSleep (const Standard_Integer aDelay)
 Commands the process to sleep for a number of seconds. More...
 
static void MilliSecSleep (const Standard_Integer aDelay)
 Commands the process to sleep for a number of milliseconds. More...
 
static Standard_Boolean RealToCString (const Standard_Real aReal, Standard_PCharacter &aString)
 Converts aReal into aCstring in exponential format with a period as decimal point, no thousand separator and no grouping of digits. The conversion is independant from the current locale. More...
 
static Standard_Boolean CStringToReal (const Standard_CString aString, Standard_Real &aReal)
 Converts aCstring representing a real with a period as decimal point, no thousand separator and no grouping of digits into aReal . The conversion is independant from the current locale. More...
 
static void ControlBreak ()
 since Windows NT does not support 'SIGINT' signal like UNIX, then this method checks whether Ctrl-Break keystroke was or not. If yes then raises Exception_CTRL_BREAK. More...
 

Detailed Description

Set of Operating Sytem Dependent (OSD) Tools.

Member Function Documentation

◆ ControlBreak()

static void OSD::ControlBreak ( )
static

since Windows NT does not support 'SIGINT' signal like UNIX, then this method checks whether Ctrl-Break keystroke was or not. If yes then raises Exception_CTRL_BREAK.

◆ CStringToReal()

static Standard_Boolean OSD::CStringToReal ( const Standard_CString  aString,
Standard_Real aReal 
)
static

Converts aCstring representing a real with a period as decimal point, no thousand separator and no grouping of digits into aReal . The conversion is independant from the current locale.

◆ MilliSecSleep()

static void OSD::MilliSecSleep ( const Standard_Integer  aDelay)
static

Commands the process to sleep for a number of milliseconds.

◆ RealToCString()

static Standard_Boolean OSD::RealToCString ( const Standard_Real  aReal,
Standard_PCharacter aString 
)
static

Converts aReal into aCstring in exponential format with a period as decimal point, no thousand separator and no grouping of digits. The conversion is independant from the current locale.

◆ SecSleep()

static void OSD::SecSleep ( const Standard_Integer  aDelay)
static

Commands the process to sleep for a number of seconds.

◆ SetFloatingSignal()

static void OSD::SetFloatingSignal ( Standard_Boolean  theFloatingSignal)
static

Enables / disables generation of C signal on floating point exceptions (FPE). This call does NOT register a handler for signal raised in case of FPE - SetSignal() should be called beforehand for complete setup. Note that FPE setting is thread-local, new threads inherit it from parent.

◆ SetSignal() [1/2]

static void OSD::SetSignal ( OSD_SignalMode  theSignalMode,
Standard_Boolean  theFloatingSignal 
)
static

Sets or removes signal and FPE (floating-point exception) handlers. OCCT signal handlers translate signals raised by C subsystem to C++ exceptions inheriting Standard_Failure.

Windows-specific notes

Compiled with MS VC++ sets 3 main handlers:

  • Signal handlers (via ::signal() functions) that translate system signals (SIGSEGV, SIGFPE, SIGILL) into C++ exceptions (classes inheriting Standard_Failure). They only be called if function ::raise() is called with one of supported signal type set.
  • Exception handler OSD::WntHandler() (via ::SetUnhandledExceptionFilter()) that will be used when user's code is compiled with /EHs option.
  • Structured exception (SE) translator (via _set_se_translator()) that translates SE exceptions (aka asynchronous exceptions) into the C++ exceptions inheriting Standard_Failure. This translator will be used when user's code is compiled with /EHa option.

This approach ensures that regardless of the option the user chooses to compile his code with (/EHs or /EHa), signals (or SE exceptions) will be translated into Open CASCADE C++ exceptions.

MinGW should use SEH exception mode for signal handling to work.

Linux-specific notes

OSD::SetSignal() sets handlers (via ::sigaction()) for multiple signals (SIGFPE, SIGSEGV, etc).

Common notes

If theFloatingSignal is TRUE then floating point exceptions will generate SIGFPE in accordance with the mask

  • Windows: _EM_INVALID | _EM_DENORMAL | _EM_ZERODIVIDE | _EM_OVERFLOW, see _controlfp() system function.
  • Linux: FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW, see feenableexcept() system function.

If theFloatingSignal is FALSE then floating point calculations will gracefully complete regardless of occurred exceptions (e.g. division by zero). Otherwise the (thread-specific) FPE flags are set to raise signal if one of floating-point exceptions (division by zero, overflow, or invalid operation) occurs.

The recommended approach is to call OSD::SetSignal() in the beginning of the execution of the program, in function main() or its equivalent. In multithreaded programs it is advisable to call OSD::SetSignal() or OSD::SetThreadLocalSignal() with the same parameters in other threads where OCCT is used, to ensure consistency of behavior.

Note that in order to handle signals as C++ exceptions on Linux and under MinGW on Windows it is necessary to compile both OCCT and application with OCC_CONVERT_SIGNALS macro, and use macro OCC_CATCH_SIGNALS within each try{} block that has to catch this kind of exceptions.

Refer to documentation of Standard_ErrorHandler.hxx for details.

◆ SetSignal() [2/2]

static void OSD::SetSignal ( const Standard_Boolean  theFloatingSignal = Standard_True)
inlinestatic

Sets signal and FPE handlers. Short-cut for OSD::SetSignal (OSD_SignalMode_Set, theFloatingSignal).

◆ SetThreadLocalSignal()

static void OSD::SetThreadLocalSignal ( OSD_SignalMode  theSignalMode,
Standard_Boolean  theFloatingSignal 
)
static

Initializes thread-local signal handlers. This includes _set_se_translator() on Windows platform, and SetFloatingSignal(). The main purpose of this method is initializing handlers for newly created threads without overriding global handlers (set by application or by OSD::SetSignal()).

◆ SignalMode()

static OSD_SignalMode OSD::SignalMode ( )
static

Returns signal mode set by the last call to SetSignal(). By default, returns OSD_SignalMode_AsIs.

◆ ToCatchFloatingSignals()

static Standard_Boolean OSD::ToCatchFloatingSignals ( )
static

Returns true if floating point exceptions will raise C signal according to current (platform-dependent) settings in this thread.


The documentation for this class was generated from the following file: