From: Alan Cox <alan@linux.intel.com>
Date: Fri, 16 Jan 2015 15:51:59 +0000 (+0000)
Subject: 6502: syscall return helper so we can set up errno correctly
X-Git-Url: https://git.ndcode.org/public/gitweb.cgi?a=commitdiff_plain;h=6f2ed105732d11d3c9713d534e1d9c26c7ed92a0;p=FUZIX.git

6502: syscall return helper so we can set up errno correctly
---

diff --git a/Library/libs/fuzix6502/syscall.s b/Library/libs/fuzix6502/syscall.s
new file mode 100644
index 00000000..53e3eab7
--- /dev/null
+++ b/Library/libs/fuzix6502/syscall.s
@@ -0,0 +1,18 @@
+	.export __syscall
+	.import _errno
+
+.proc __syscall
+	jsr	callfe
+	bne	error
+	tya		; x,a form the return code
+	rts
+error:
+	sta	_errno
+	ldx	#0
+	stx	_errno+1
+	dex	;	Return $FFFF (-1)
+	txa
+	rts
+callfe:	jmp	($fe)
+
+.endproc