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-rw-r--r--lib_i386/bios.h94
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diff --git a/lib_i386/bios.h b/lib_i386/bios.h
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+++ b/lib_i386/bios.h
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+/*
+ * (C) Copyright 2002
+ * Daniel Engström, Omicron Ceti AB, daniel@omicron.se
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program 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 2 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#ifndef _BIOS_H_
+#define _BIOS_H_
+
+#define OFFS_ES 0 /* 16bit */
+#define OFFS_GS 2 /* 16bit */
+#define OFFS_DS 4 /* 16bit */
+#define OFFS_EDI 6 /* 32bit */
+#define OFFS_DI 6 /* low 16 bits of EDI */
+#define OFFS_ESI 10 /* 32bit */
+#define OFFS_SI 10 /* low 16 bits of ESI */
+#define OFFS_EBP 14 /* 32bit */
+#define OFFS_BP 14 /* low 16 bits of EBP */
+#define OFFS_ESP 18 /* 32bit */
+#define OFFS_SP 18 /* low 16 bits of ESP */
+#define OFFS_EBX 22 /* 32bit */
+#define OFFS_BX 22 /* low 16 bits of EBX */
+#define OFFS_BL 22 /* low 8 bits of BX */
+#define OFFS_BH 23 /* high 8 bits of BX */
+#define OFFS_EDX 26 /* 32bit */
+#define OFFS_DX 26 /* low 16 bits of EBX */
+#define OFFS_DL 26 /* low 8 bits of BX */
+#define OFFS_DH 27 /* high 8 bits of BX */
+#define OFFS_ECX 30 /* 32bit */
+#define OFFS_CX 30 /* low 16 bits of EBX */
+#define OFFS_CL 30 /* low 8 bits of BX */
+#define OFFS_CH 31 /* high 8 bits of BX */
+#define OFFS_EAX 34 /* 32bit */
+#define OFFS_AX 34 /* low 16 bits of EBX */
+#define OFFS_AL 34 /* low 8 bits of BX */
+#define OFFS_AH 35 /* high 8 bits of BX */
+#define OFFS_VECTOR 38 /* 16bit */
+#define OFFS_IP 40 /* 16bit */
+#define OFFS_CS 42 /* 16bit */
+#define OFFS_FLAGS 44 /* 16bit */
+
+#define SEGMENT 0x40
+#define STACK 0x800 /* stack at 0x40:0x800 -> 0x800 */
+
+/* save general registers */
+/* save some segments */
+/* save callers stack segment .. */
+/* ... in gs */
+ /* setup my segments */
+ /* setup BIOS stackpointer */
+
+#define MAKE_BIOS_STACK \
+ pushal ; \
+ pushw %ds ; \
+ pushw %gs ; \
+ pushw %es ; \
+ pushw %ss ; \
+ popw %gs ; \
+ movw $SEGMENT,%ax ; \
+ movw %ax,%ds ; \
+ movw %ax,%es ; \
+ movw %ax,%ss ; \
+ movw %sp,%bp ; \
+ movw $STACK,%sp
+
+#define RESTORE_CALLERS_STACK \
+ pushw %gs ; /* restore callers stack segment */ \
+ popw %ss ; \
+ movw %bp,%sp ; /* restore stackpointer */ \
+ \
+ popw %es ; /* restore segment selectors */ \
+ popw %gs ; \
+ popw %ds ; \
+ \
+ popal /* restore GP registers */
+
+#endif