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71 lines
1.7 KiB
ArmAsm
71 lines
1.7 KiB
ArmAsm
;
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; Ullrich von Bassewitz, 2002-12-16
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;
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; __sigfunc __fastcall__ signal (int sig, __sigfunc func);
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;
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.import popax
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.importzp ptr1
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.include "signal.inc"
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.include "errno.inc"
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; Default signal functions: The standard specifies explicitly that the values
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; for SIG_IGN and SIG_DFL must be distinct, so we make them so by using both
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; rts exits we have. This works because signal functions are __fastcall__, so
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; we don't have arguments on the stack.
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;----------------------------------------------------------------------------
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; __sigfunc __fastcall__ signal (int sig, __sigfunc func);
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_signal:
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sta ptr1
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stx ptr1+1 ; Remember func
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jsr popax ; Get sig
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cpx #0
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bne invalidsig
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cmp #SIGCOUNT
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bcs invalidsig
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; Signal number is valid. Replace the pointer in the table saving the old
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; value temporarily on the stack.
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asl a ; Prepare for word access
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tax
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sei ; Disable interrupts in case of async signals
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lda sigtable,x
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pha
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lda ptr1
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sta sigtable,x
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lda sigtable+1,x
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pha
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lda ptr1+1
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sta sigtable+1,x
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cli ; Reenable interrupts
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; Get the old value from the stack and return it
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pla
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tax
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pla
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__sig_ign:
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rts
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; Error entry: We use our knowledge that SIG_ERR is zero here to save a byte
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invalidsig:
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lda #<EINVAL
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sta __errno
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lda #>EINVAL ; A = 0
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sta __errno+1
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tax ; A/X = 0
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__sig_dfl:
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rts
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