Thread: Am I error checking too much ?

Hi. I'm a newb trying to learn C99. Here's some code that I wrote. My intention is to write a Wikipedia bot that uses libcurl. I wonder if I'm going over the top on error checking, or if I'm within acceptable boundaries.

Code:

#include <stdio.h>
#include <string.h>
#include <time.h>
#include "Internetfunctions.h"
#include "Error.h"

#define StringMax 100

static int shutdownmessage ( void )	
{
	int nonfatalerror = 0 ;		/* = 1 for nonfatal error, -1 for fatal error. */

		/* Print shutdown message. */

	int printingerror = 0 ;
	char* p_Message = "Bot shutting down now.\n" ;
	if ( printf ( "%s", p_Message ) != strlen ( p_Message ) )
		printingerror = 1 ;

	if ( printingerror )
	{
		ErrorMessage ( "Couldn't print to screen." , __FILE__ , __LINE__ );
		nonfatalerror = 1;
	}

		/* Print shutdown time */	

	struct tm *local ;
	time_t currenttime ;
	char Message [ StringMax ] ;

	if ( time ( &currenttime ) != -1 ) 
	{
		local = localtime ( &currenttime ) ;
		int x = snprintf ( Message , StringMax , "Bot shutdown at : %s" , asctime ( local ) ) ;
		if ( printf ( "%s", Message ) != strlen ( Message ) )
		{
			ErrorMessage ( "Couldn't print to screen." , __FILE__ , __LINE__ );
			nonfatalerror = 1 ;
		}
	}
	else
	{
		ErrorMessage ( "Current local time is not available." , __FILE__ , __LINE__ );
		nonfatalerror = 1 ;
	}

	return nonfatalerror ;
}

int shutdown ( void )
{
	int x = finalizeinternetfunctions () ;
	if ( x < 0 ) return x ;

	int y = shutdownmessage () ;
	if ( y < 0 ) return y ;

	if ( x > 0 ) return x ;
	else
	if ( y > 0 ) return y ;

	return 0 ;
}

Originally Posted by Richardcavell

Hi. I'm a newb trying to learn C99. Here's some code that I wrote. My intention is to write a Wikipedia bot that uses libcurl. I wonder if I'm going over the top on error checking, or if I'm within acceptable boundaries.

You're a bit over the top... most of the print to screen and memory functions are highly trustworthy. Besides... if printing to the screen is not working, how do you plan to display the error message?

The stuff you need to be checking are the I/O functions where "crap happens" far more often; networking, file I/O, serial comms, memory allocations etc.

Code:

#include <stdio.h>
#include <string.h>
#include <time.h>
#include "Internetfunctions.h"
#include "Error.h"

#define StringMax 100

static int shutdownmessage ( void )	
{
//	int nonfatalerror = 0 ;		/* = 1 for nonfatal error, -1 for fatal error. */

		/* Print shutdown message. */

//	int printingerror = 0 ;
//	char* p_Message = "Bot shutting down now.\n" ;
//	if ( printf ( "%s", p_Message ) != strlen ( p_Message ) )
//		printingerror = 1 ;

printf("Bot Shutting down now.\n");

//	if ( printingerror )
//	{
//		ErrorMessage ( "Couldn't print to screen." , __FILE__ , __LINE__ );
//		nonfatalerror = 1;
//	}

// NOTE: Printing __LINE__ only works with debug code in your files. 
// release versions don't know line numbers.


		/* Print shutdown time */	

	struct tm *local ;
	time_t currenttime ;
	char Message [ StringMax ] ;

	if ( time ( &currenttime ) != -1 ) 
	{
		local = localtime ( &currenttime ) ;
//		int x = snprintf ( Message , StringMax , "Bot shutdown at : %s" , asctime ( local ) ) ;

printf("Bot Shutdown at : %s" asctime(local));

//		if ( printf ( "%s", Message ) != strlen ( Message ) )
//		{
//			ErrorMessage ( "Couldn't print to screen." , __FILE__ , __LINE__ );
//			nonfatalerror = 1 ;
//		}
//	}
//	else
//	{
//		ErrorMessage ( "Current local time is not available." , __FILE__ , __LINE__ );
//		nonfatalerror = 1 ;
//	}

//	return nonfatalerror ;
}

int shutdown ( void )
{
shutdownmessage(); 

	int x = finalizeinternetfunctions () ;
	if ( x < 0 ) 
                  return x ;
  

//	int y = shutdownmessage () ;
//	if ( y < 0 ) return y ;

//	if ( x > 0 ) return x ;
//	else
//	if ( y > 0 ) return y ;

	return 0 ;
}