Gyoto::Error Class Reference

Class for thowing exceptions. More...

#include <GyotoError.h>

Public Types
typedef void	Handler_t(const Error)
	Error handler type. More...

Public Member Functions
	Error (const std::string m)
	Constructor with an error message.
	Error (const Gyoto::Error &o)
void	Report () const
	Print-out error message on standard error.
int	getErrcode () const
	Retrieve error code. More...
	operator const char * () const
	Cast to const char *. More...
std::string	get_message () const
	Retrieve error message for custom handling of the exception. More...

Static Public Member Functions
static void	setHandler (Gyoto::Error::Handler_t *phandler)
	Set application error handler. More...

Private Attributes
const std::string	message
	Error message.
const int	errcode
	Error code. More...

Detailed Description

Class for thowing exceptions.

Gyoto dlopens its plug-ins. The throw/catch C++ mechanism cannot pass the dlopen boundary. The Gyoto::Error mechanism alleviates this C++ language limitation.

Every Gyoto method (either in the main Gyoto library or in a Gyoto plug-in) should check for possible error conditions and throw adequate Gyoto::Error exceptions through the GYOTO_ERROR macro (which calls the Gyoto::throwError() function). For instance:

if (error_condition) GYOTO_ERROR("Useful error message");

If the main code has set Gyoto::Error::handler_t error handler using Gyoto::Error::setHandler(), these errors will then be passed to it. Else, the Error is C++-thrown at the main Gyoto library level, above the dlopen boundary.

The main code can then catch these exceptions and act appropriately, for instance:

try { gyoto_code ; }
catch (Gyoto::Error err)
{
   err.Report();
   abort();
}

Member Typedef Documentation

Handler_t

typedef void Gyoto::Error::Handler_t(const Error)

Error handler type.

Instead of catching Gyoto errors directly (for instance if gyoto itself is dlopened), you can set a Handler_t error handler using setHandler().

A very simple handler could be:

void applicationErrorHandler(const Gyoto::Error e) {
  e.Report();
  exit ( e.getErrCode() );
}

Member Function Documentation

get_message()

std::string Gyoto::Error::get_message

(

)

const

Retrieve error message for custom handling of the exception.

See also operator const char * () const and getErrCode().

Returns

char* message : pointer to the error message

getErrcode()

int Gyoto::Error::getErrcode

(

)

const

Retrieve error code.

See also operator const char * () const and get_message().

Returns

Error code

operator const char *()

Gyoto::Error::operator const char *

(

)

const

Cast to const char *.

Retrieve error message as a C string. See also get_message() and gerErrcode().

setHandler()

static void Gyoto::Error::setHandler ( Gyoto::Error::Handler_t *  phandler )

static

Set application error handler.

Instead of catching Gyoto errors directly (for instance if gyoto itself is dlopened), you can set an Error::Handler_t error handler using setHandler().

void applicationErrorHandler(const Gyoto::Error e) {
  e.Report();
  exit ( e.getErrCode() );
}
int main() {
  Gyoto::Error::setHandler(&applicationErrorHandler);
}

Parameters

phandler

Function pointer to the handler.

Member Data Documentation

errcode

const int Gyoto::Error::errcode

private

Error code.

Default value is EXIT_FAILURE from cstdlib. Currently not used in practice.

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

• GyotoError.h