--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lwasm/os9.c	Wed Jan 19 22:27:17 2011 -0700
@@ -0,0 +1,191 @@
+/*
+os9.c
+Copyright © 2009 William Astle
+
+This file is part of LWASM.
+
+LWASM is free software: you can redistribute it and/or modify it under the
+terms of the GNU General Public License as published by the Free Software
+Foundation, either version 3 of the License, or (at your option) any later
+version.
+
+This program is distributed in the hope that it will be useful, but WITHOUT
+ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+more details.
+
+You should have received a copy of the GNU General Public License along with
+this program. If not, see <http://www.gnu.org/licenses/>.
+
+
+This file implements the various pseudo operations related to OS9 target
+*/
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <lw_expr.h>
+
+#include "lwasm.h"
+#include "instab.h"
+
+
+// OS9 syscall
+PARSEFUNC(pseudo_parse_os9)
+{
+	lw_expr_t e;
+	
+	if (as -> output_format != OUTPUT_OS9)
+	{
+		lwasm_register_error(as, l, "os9 directive only valid for OS9 target");
+		return;
+	}
+	
+	// fetch immediate value
+	e = lwasm_parse_expr(as, p);
+	if (!e)
+	{
+		lwasm_register_error(as, l, "Bad operand");
+		return;
+	}
+	lwasm_save_expr(l, 0, e);
+	l -> len = 3;
+}
+
+EMITFUNC(pseudo_emit_os9)
+{
+	lw_expr_t e;
+	
+	e = lwasm_fetch_expr(l, 0);
+
+	lwasm_emitop(l, 0x103f);
+	lwasm_emitexpr(l, e, 1);
+}
+
+PARSEFUNC(pseudo_parse_mod)
+{
+	lw_expr_t e;
+	int i;
+	
+	if (as -> output_format != OUTPUT_OS9)
+	{
+		lwasm_register_error(as, l,  "mod directive only valid for OS9 target");
+		return;
+	}
+	
+	if (as -> inmod)
+	{
+		lwasm_register_error(as, l,  "Already in a module!");
+		return;
+	}
+
+	// parse 6 expressions...
+	for (i = 0; i < 5; i++)
+	{
+		e = lwasm_parse_expr(as, p);
+		if (!e)
+		{
+			lwasm_register_error(as, l, "Bad operand");
+			return;
+		}
+
+		lwasm_save_expr(l, i, e);
+
+		if (**p != ',')
+		{
+			lwasm_register_error(as, l, "Bad operand");
+			return;
+		}
+		(*p)++;
+	}
+
+	e = lwasm_parse_expr(as, p);
+	if (!e)
+	{
+		lwasm_register_error(as, l, "Bad operand");
+		return;
+	}
+	lwasm_save_expr(l, 5, e);
+
+	l -> inmod = 1;
+	
+	// we have an implicit ORG 0 with "mod"
+	lw_expr_destroy(l -> addr);
+	l -> addr = lw_expr_build(lw_expr_type_int, 0);
+
+	// init crc
+	as -> inmod = 1;
+}
+
+EMITFUNC(pseudo_emit_mod)
+{
+	lw_expr_t e1, e2, e3, e4;
+	int csum;
+	
+	as -> crc[0] = 0xff;
+	as -> crc[1] = 0xff;
+	as -> crc[2] = 0xff;
+
+	// sync bytes
+	lwasm_emit(l, 0x87);
+	lwasm_emit(l, 0xcd);
+	
+	// mod length
+	lwasm_emitexpr(l, e1 = lwasm_fetch_expr(l, 0), 2);
+	
+	// name offset
+	lwasm_emitexpr(l, e2 = lwasm_fetch_expr(l, 1), 2);
+	
+	// type
+	lwasm_emitexpr(l, e3 = lwasm_fetch_expr(l, 2), 1);
+	
+	// flags/rev
+	lwasm_emitexpr(l, e4 = lwasm_fetch_expr(l, 3), 1);
+	
+	// header check
+	csum = ~(0x87 ^ 0xCD ^(lw_expr_intval(e1) >> 8) ^ (lw_expr_intval(e1) & 0xff)
+		^ (lw_expr_intval(e2) >> 8) ^ (lw_expr_intval(e2) & 0xff)
+		^ lw_expr_intval(e3) ^ lw_expr_intval(e4));
+	lwasm_emit(l, csum);
+
+	// module type specific output
+	// note that these are handled the same for all so
+	// there need not be any special casing
+	
+	// exec offset or fmgr name offset
+	lwasm_emitexpr(l, lwasm_fetch_expr(l, 4), 2);
+	
+	// data size or drvr name offset
+	lwasm_emitexpr(l, lwasm_fetch_expr(l, 5), 2);
+}
+
+PARSEFUNC(pseudo_parse_emod)
+{
+	if (as -> output_format != OUTPUT_OS9)
+	{
+		lwasm_register_error(as, l, "emod directive only valid for OS9 target");
+		return;
+	}
+	
+	if (!(as -> inmod))
+	{
+		lwasm_register_error(as, l, "not in a module!");
+		return;
+	}
+	
+	as -> inmod = 0;
+}
+
+EMITFUNC(pseudo_emit_emod)
+{
+	unsigned char tcrc[3];
+	
+	// don't mess with CRC!
+	tcrc[0] = as -> crc[0] ^ 0xff;
+	tcrc[1] = as -> crc[1] ^ 0xff;
+	tcrc[2] = as -> crc[2] ^ 0xff;
+	lwasm_emit(l, tcrc[0]);
+	lwasm_emit(l, tcrc[1]);
+	lwasm_emit(l, tcrc[2]);
+}