1
0
mirror of https://github.com/cc65/cc65.git synced 2024-12-24 11:31:31 +00:00
cc65/libsrc/atari/read.s

34 lines
672 B
ArmAsm
Raw Normal View History

;
; Christian Groessler, Apr-2000
;
; int read(int fd,void *buf,int count)
;
.include "atari.inc"
.import __rwsetup,__do_oserror,__inviocb,__oserror
.export _read
_read: jsr __rwsetup ; do common setup for read and write
beq done ; if size 0, it's a no-op
cpx #$FF ; invalid iocb?
beq _inviocb
lda #GETCHR ; iocb command code
sta ICCOM,x
jsr CIOV ; read it
bpl done
cpy #EOFERR ; eof is treated specially
beq done
jmp __do_oserror ; update errno
done: lda ICBLL,x ; buf len lo
pha ; save
lda ICBLH,x ; get buf len hi
tax ; to X
lda #0
sta __oserror ; clear system dependend error code
pla ; get buf len lo
rts
_inviocb:
jmp __inviocb