Auto-assign drive number only if set to 0xff; almost all applications

require that we use drive 0x80, so it should probably be the default.

diff --git a/src/arch/i386/interface/pcbios/int13.c b/src/arch/i386/interface/pcbios/int13.c
index 53817c7..a26dcff 100644 (file)
--- a/src/arch/i386/interface/pcbios/int13.c
+++ b/src/arch/i386/interface/pcbios/int13.c
@@ -543,8 +543,9 @@ void register_int13_drive ( struct int13_drive *drive ) {
 
        /* Assign drive number if none specified, update BIOS drive count */
        get_real ( num_drives, BDA_SEG, BDA_NUM_DRIVES );
 
        /* Assign drive number if none specified, update BIOS drive count */
        get_real ( num_drives, BDA_SEG, BDA_NUM_DRIVES );

-       if ( ! drive->drive )
-               drive->drive = ( num_drives | 0x80 );
+       if ( ( drive->drive & 0xff ) == 0xff )
+               drive->drive = num_drives;
+       drive->drive |= 0x80;

        num_drives++;
        if ( num_drives <= ( drive->drive & 0x7f ) )
                num_drives = ( ( drive->drive & 0x7f ) + 1 );
        num_drives++;
        if ( num_drives <= ( drive->drive & 0x7f ) )
                num_drives = ( ( drive->drive & 0x7f ) + 1 );