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cc65/libsrc/common/strerror.s
cuz 87fa3fbdaa Minor optimization
git-svn-id: svn://svn.cc65.org/cc65/trunk@1358 b7a2c559-68d2-44c3-8de9-860c34a00d81
2002-07-16 09:41:00 +00:00

29 lines
571 B
ArmAsm

;
; Ullrich von Bassewitz, 17.05.2000
;
; char* __fastcall__ strerror (int errcode);
; /* Map an error number to an error message */
;
.export _strerror
.import __sys_errlist
.include "errno.inc"
_strerror:
cpx #$00 ; High byte must be zero
bne @L1 ; Jump if invalid error
cmp #EMAX ; Valid error code (map EUNKNOWN to 0)?
bcc @L2 ; Jump if ok
@L1: lda #$00 ; "Unknown error"
@L2: asl a ; * 2
tay
; Load the pointer to the error message and return
ldx __sys_errlist+1,y
lda __sys_errlist,y
rts