Register arguments can be passed to v86 code

v86defs.h

@@ -0,0 +1,51 @@
+#include <stdint.h>
+
+extern void v86Test();
+extern void v86TransFlag();
+extern void v86GfxMode();
+extern void v86TextMode();
+extern void v86DiskRead();
+extern void v86VideoInt();
+
+union __attribute((__packed__)) V86Regs_t {
+    struct dword_regs { 
+        uint32_t edi;
+        uint32_t esi;
+        uint32_t ebx;
+        uint32_t edx;
+        uint32_t ecx;
+        uint32_t eax;
+    } d;
+    struct word_regs { 
+        uint16_t di, _upper_di;
+        uint16_t si, _upper_si;
+        uint16_t bx, _upper_bx;
+        uint16_t dx, _upper_dx;
+        uint16_t cx, _upper_cx;
+        uint16_t ax, _upper_ax;
+    } w;
+    struct byte_regs { 
+        uint16_t di, _upper_di;
+        uint16_t si, _upper_si;
+        uint8_t bl, bh;
+        uint16_t _upper_bx;
+        uint8_t dl, dh;
+        uint16_t _upper_dx;
+        uint8_t cl, ch;
+        uint16_t _upper_cx;
+        uint8_t al, ah;
+        uint16_t _upper_ax;
+    } h;
+};
+
+extern void enter_v86(uint32_t ss, uint32_t esp, uint32_t cs, uint32_t eip, union V86Regs_t *regs);
+
+struct __attribute((__packed__)) Int13DiskPacket_t {
+    uint8_t size; // 0x10
+    uint8_t reserved; // 0x00
+    uint16_t blocks;
+    uint32_t transfer_buffer; // 0x2300:0000
+    uint64_t start_block;
+};
+
+extern struct Int13DiskPacket_t v86disk_addr_packet;