mirror of
https://github.com/hsoft/collapseos.git
synced 2024-12-27 18:48:05 +11:00
31a58d00f1
Among random "better safe than sorry" changes, the real fix is in changing "4" for "5" above _find declaration. This off-by-one error had that word, which is the root word in z80, have a 0x01 prev field instead of a 0x00 one. When all memory was initialized to zero, it didn't matter, we ended up hitting 0 prev and considered ourselves properly at the end of dict. When memory wasn't initialized, however, we would end up jumping at all kinds of places, leading to random behavior.
17 lines
686 B
Plaintext
17 lines
686 B
Plaintext
( Native words )
|
|
H@ 5 + XCURRENT ! ( make next CODE have 0 prev field )
|
|
CODE _find ( cur w -- a f )
|
|
HL POP, ( w ) DE POP, ( cur ) chkPS,
|
|
HL PUSH, ( --> lvl 1 )
|
|
( First, figure out string len )
|
|
A (HL) LDrr, A ORr,
|
|
( special case. zero len? we never find anything. )
|
|
IFZ, PUSH0, JPNEXT, THEN,
|
|
BC PUSH, ( --> lvl 2, protect )
|
|
( Let's do something weird: We'll hold HL by the *tail*.
|
|
Because of our dict structure and because we know our
|
|
lengths, it's easier to compare starting from the end. )
|
|
C A LDrr, B 0 LDri, ( C holds our length )
|
|
BC ADDHLd, HL INCd, ( HL points to after-last-char )
|
|
( cont . )
|