fault.c File Reference

Fault injection. More...

#include <stdlib.h>
#include <errno.h>
#include <ipxe/fault.h>

Go to the source code of this file.

Functions
	FILE_LICENCE (GPL2_OR_LATER_OR_UBDL)
int	inject_fault_nonzero (unsigned int rate)
	Inject fault with a specified probability. More...
void	inject_corruption_nonzero (unsigned int rate, const void *data, size_t len)
	Corrupt data with a specified probability. More...

Detailed Description

Fault injection.

Definition in file fault.c.

Function Documentation

FILE_LICENCE()

FILE_LICENCE

(

GPL2_OR_LATER_OR_UBDL

)

inject_fault_nonzero()

int inject_fault_nonzero

(

unsigned int

rate

)

Inject fault with a specified probability.

Parameters

rate	Reciprocal of fault probability (must be non-zero)

Return values

rc	Return status code

Definition at line 42 of file fault.c.

                                               {

        /* Do nothing unless we want to inject a fault now */
        if ( ( random() % rate ) != 0 )
                return 0;

        /* Generate error number here so that faults can be injected
         * into files that don't themselves have error file
         * identifiers (via errfile.h).
         */
        return -EFAULT;
}

References EFAULT, and random().

Referenced by __attribute__(), and inject_corruption_nonzero().

inject_corruption_nonzero()

void inject_corruption_nonzero	(	unsigned int	rate,
		const void *	data,
		size_t	len
	)

Corrupt data with a specified probability.

Parameters

rate	Reciprocal of fault probability (must be non-zero)
data	Data
len	Length of data

Return values

rc	Return status code

Definition at line 63 of file fault.c.

                                              {
        uint8_t *writable;
        size_t offset;

        /* Do nothing if we have no data to corrupt */
        if ( ! len )
                return;

        /* Do nothing unless we want to inject a fault now */
        if ( ! inject_fault_nonzero ( rate ) )
                return;

        /* Get a writable pointer to the nominally read-only data */
        writable = ( ( uint8_t * ) data );

        /* Pick a random victim byte and zap it */
        offset = ( random() % len );
        writable[offset] ^= random();
}

References data, inject_fault_nonzero(), len, offset, and random().