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Added debugging statements

This commit is contained in:
Michael Brown 2007-01-08 03:04:54 +00:00
parent 239965ff3b
commit a6ba48e51e
1 changed files with 19 additions and 1 deletions
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20
src/arch/i386/interface/pcbios/biosint.c
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@ -37,13 +37,21 @@ void hook_bios_interrupt ( unsigned int interrupt, unsigned int handler,
.offset = handler,
};
DBG ( "Hooking INT %#02x to %04x:%04x\n",
interrupt, rm_cs, handler );
if ( ( chain_vector->segment != 0 ) ||
( chain_vector->offset != 0 ) ) {
/* Already hooked; do nothing */
DBG ( "...already hooked\n" );
return;
}
copy_from_real ( chain_vector, 0, ( interrupt * 4 ),
sizeof ( *chain_vector ) );
DBG ( "...chaining to %04x:%04x\n",
chain_vector->segment, chain_vector->offset );
copy_to_real ( 0, ( interrupt * 4 ), &vector, sizeof ( vector ) );
hooked_bios_interrupts++;
}
@ -65,11 +73,21 @@ int unhook_bios_interrupt ( unsigned int interrupt, unsigned int handler,
struct segoff *chain_vector ) {
struct segoff vector;
DBG ( "Unhooking INT %#02x from %04x:%04x\n",
interrupt, rm_cs, handler );
copy_from_real ( &vector, 0, ( interrupt * 4 ), sizeof ( vector ) );
if ( ( vector.segment != rm_cs ) || ( vector.offset != handler ) )
if ( ( vector.segment != rm_cs ) || ( vector.offset != handler ) ) {
DBG ( "...cannot unhook; vector points to %04x:%04x\n",
vector.segment, vector.offset );
return -EBUSY;
}
DBG ( "...restoring to %04x:%04x\n",
chain_vector->segment, chain_vector->offset );
copy_to_real ( 0, ( interrupt * 4 ), chain_vector,
sizeof ( *chain_vector ) );
chain_vector->segment = 0;
chain_vector->offset = 0;
hooked_bios_interrupts--;