Added a file selection screen (that does nothing), Moved tests to their own file, Fixed a race condition with the keyboard handler

Makefile

@@ -1,4 +1,4 @@
-objects = entry.o kernel.o task.o handler.o interrupt.o v86.o print.o tss.o dosfs/dosfs.o gdt.o usermode.o paging.o fault.o
+objects = entry.o kernel.o task.o handler.o interrupt.o v86.o print.o tss.o dosfs/dosfs.o gdt.o usermode.o paging.o fault.o tests.o
 CFLAGS = -target "i686-elf" -m32 -mgeneral-regs-only -ffreestanding -march=pentium-m -fno-stack-protector -Wno-int-conversion -nostdlib -c
 
 %.o: %.nasm

boot.nasm

@@ -1,6 +1,5 @@
 [ORG 0x7c00]
 [BITS 16]
-
 xor ax, ax
 mov ds, ax
 mov es, ax
@@ -72,5 +71,5 @@ string: db 'DISK ERROR'
 addr_packet:
 db 0x10, 0x00 ; size, reserved
 dw 0x39 ; blocks
-dd 0x8000 ; transfer buffer
+addr_packet_transfer_buff: dd 0x08000000 ; transfer buffer
-dq 1 ; start block
+addr_packet_start_block: dq 1 ; start block

fault.nasm

@@ -50,6 +50,7 @@ jmp gpf_handler_32
 gpf_unhandled:
 mov dword [error_screen+0x00], 0x0f000f00 | 'G' | 'P' << 16
 mov dword [error_screen+0x04], 0x0f000f00 | 'F' | '!' << 16
+xchg bx,bx
 jmp _fault_coda
 
 _gpf_old_ds: dw 0

interrupt.c

@@ -82,6 +82,7 @@ void IRQ_clear_mask(char IRQline) {
 }
 
 char v86_if = 0;
+extern uint16_t error_screen[80*50]; // defined in kernel.c
 extern uint16_t *ivt;
 extern void real_test();
 extern void jmp_usermode_test();
@@ -99,14 +100,14 @@ void gpf_handler_v86(struct interrupt_frame *frame, unsigned long error_code) {
     stack = FP_TO_LINEAR(frame->ss, frame->esp);
     stack32 = (uint32_t*)stack;
 
-    char *vga = (char*)0xb8000 + (160 * 10);
+    char *vga = (char*)error_screen + (160 * 10);
     vga[0] = 'I'; vga[2] = 'P'; int_printWord(frame->eip, (uint16_t*)&vga[4]); vga += 14;
     vga[0] = 'C'; vga[2] = 'S'; int_printWord(frame->cs, (uint16_t*)&vga[4]); vga += 14;
     vga[0] = 'F'; vga[2] = 'L'; int_printDword(frame->eflags, (uint16_t*)&vga[4]); vga += 14;
-    vga = (char*)0xb8000 + (160 * 11);
+    vga = (char*)error_screen + (160 * 11);
     vga[0] = 'S'; vga[2] = 'P'; int_printWord(frame->esp, (uint16_t*)&vga[4]); vga += 14;
     vga[0] = 'S'; vga[2] = 'S'; int_printWord(frame->ss, (uint16_t*)&vga[4]); vga += 14;
-    vga = (char*)0xb8000 + (160 * 12);
+    vga = (char*)error_screen + (160 * 12);
     vga[0] = 'E'; vga[2] = 'S'; int_printWord(frame->es, (uint16_t*)&vga[4]); vga += 14;
     vga[0] = 'D'; vga[2] = 'S'; int_printWord(frame->ds, (uint16_t*)&vga[4]); vga += 14;
     vga[0] = 'F'; vga[2] = 'S'; int_printWord(frame->fs, (uint16_t*)&vga[4]); vga += 14;
@@ -127,7 +128,8 @@ void gpf_handler_v86(struct interrupt_frame *frame, unsigned long error_code) {
     //    printByte(ip[i], vga);
     //    vga += (sizeof(uint8_t)*2)*2;
     //}
-    vga = (char*)0xb8000 + (160*3);
+
+    vga = (char*)error_screen + (160*3);
     for(;;) {
         switch (ip[0]) {
             case 0x66: // O32
@@ -220,14 +222,14 @@ void gpf_handler_v86(struct interrupt_frame *frame, unsigned long error_code) {
         }
     }
     done:;
-    vga = (char*)0xb8000 + (160 * 13);
+    vga = (char*)error_screen + (160 * 13);
     vga[0] = 'I'; vga[2] = 'P'; int_printWord(frame->eip, (uint16_t*)&vga[4]); vga += 14;
     vga[0] = 'C'; vga[2] = 'S'; int_printWord(frame->cs, (uint16_t*)&vga[4]); vga += 14;
     vga[0] = 'F'; vga[2] = 'L'; int_printDword(frame->eflags, (uint16_t*)&vga[4]); vga += 14;
-    vga = (char*)0xb8000 + (160 * 14);
+    vga = (char*)error_screen + (160 * 14);
     vga[0] = 'S'; vga[2] = 'P'; int_printWord(frame->esp, (uint16_t*)&vga[4]); vga += 14;
     vga[0] = 'S'; vga[2] = 'S'; int_printWord(frame->ss, (uint16_t*)&vga[4]); vga += 14;
-    vga = (char*)0xb8000 + (160 * 15);
+    vga = (char*)error_screen + (160 * 15);
     vga[0] = 'E'; vga[2] = 'S'; int_printWord(frame->es, (uint16_t*)&vga[4]); vga += 14;
     vga[0] = 'D'; vga[2] = 'S'; int_printWord(frame->ds, (uint16_t*)&vga[4]); vga += 14;
     vga[0] = 'F'; vga[2] = 'S'; int_printWord(frame->fs, (uint16_t*)&vga[4]); vga += 14;
@@ -266,9 +268,16 @@ uint8_t scancodesToAsciiShift[0x3B] =
 "\0"; // 0x3A
 uint8_t _KBDWAIT;
 uint8_t _KEYCAPS = 0, _KEYSHIFT = 0;
-uint8_t _LSTKEY = 0;
+uint8_t _LSTKEY_ASCII = 0, _LSTKEY_SCAN = 0;
 __attribute__ ((interrupt))
 void keyboardHandler(struct interrupt_frame *frame) {
+    uint16_t old_ds;
+    asm volatile(
+        "mov %%ds, %%bx\n"
+        "mov $0x10, %%ax\n"
+        "mov %%ax, %%ds\n"
+        :"=b"(old_ds)::"%ax"
+    );
     uint8_t key;
     asm volatile("inb $0x60, %%al":"=a"(key));
     if (key == 0x3A) { // caps lock press
@@ -282,11 +291,19 @@ void keyboardHandler(struct interrupt_frame *frame) {
             scancodesToAsciiShift[key] :
             scancodesToAscii[key];
         if (ascii) {
-            _LSTKEY = ascii;
+            _LSTKEY_ASCII = ascii;
+            _LSTKEY_SCAN = key;
             _KBDWAIT = 1;
         }
+    } else {
+        _LSTKEY_ASCII = 0;
+        _LSTKEY_SCAN = key;
     }
     asm volatile("outb %%al, $0x20"::"a"(0x20));
+    asm volatile(
+        "mov %%ax, %%ds\n"
+        ::"a"(old_ds)
+    );
 }
 
 __attribute((__no_caller_saved_registers__))
@@ -299,11 +316,21 @@ void kbd_wait() {
 
 __attribute((__no_caller_saved_registers__))
 uint8_t get_key() {
-    while(!_LSTKEY) {
+    while(!_LSTKEY_ASCII) {
         asm volatile("hlt");
     }
-    uint8_t k = _LSTKEY;
+    uint8_t k = _LSTKEY_ASCII;
-    _LSTKEY = 0;
+    _LSTKEY_ASCII = 0;
+    return k;
+}
+__attribute((__no_caller_saved_registers__))
+uint16_t get_scancode() {
+    while(!_LSTKEY_SCAN) {
+        asm volatile("hlt");
+    }
+    uint16_t k = _LSTKEY_SCAN | (_LSTKEY_ASCII << 8);
+    _LSTKEY_SCAN = 0;
+    _LSTKEY_ASCII = 0;
     return k;
 }
 

interrupt.h

@@ -1,3 +1,4 @@
+#pragma once
 #include <stdint.h>
 
 struct interrupt_frame {
@@ -33,6 +34,8 @@ void kbd_wait();
 
 __attribute((__no_caller_saved_registers__))
 uint8_t get_key();
+__attribute((__no_caller_saved_registers__))
+uint16_t get_scancode();
 
 __attribute__ ((interrupt))
 void gpf_handler_v86(struct interrupt_frame *frame, unsigned long error_code);

kernel.c

@@ -6,6 +6,7 @@
 #include "tss.h"
 #include "paging.h"
 #include "v86defs.h"
+#include "tests.h"
 
 typedef unsigned short word;
 
@@ -54,8 +55,6 @@ uint32_t get_cr4() {
     return reg;
 }
 
-extern char *jmp_usermode_test();
-
 extern char _edata, _v86code, _ev86code, _bstart, _bend, _loadusercode, _usercode, _eusercode;
 void setup_binary() {
     // Put V86 code in proper place based on linker
@@ -142,95 +141,62 @@ Protected Only (1MB+)
 400000 - 700000 Usermode Code (3mB)
 700000 - 800000 Usermode Stack (1mB)
 */
-
+void DrawScreen() {
-void TestV86() {
+    uint16_t *vga_text = (uint16_t *)0xB8000;
-    union V86Regs_t regs;
+    // clear screen
-    regs.d.edi = 0x11111111;
-    regs.d.esi = 0x22222222;
-    regs.d.ebx = 0x33333333;
-    regs.d.edx = 0x44444444;
-    regs.d.ecx = 0x55555555;
-    regs.d.eax = 0x66666666;
-    FARPTR v86_entry = i386LinearToFp(v86Test);
-    enter_v86(0x8000, 0xFF00, FP_SEG(v86_entry), FP_OFF(v86_entry), &regs);
-}
-void TestUser() {
-    char *vga = jmp_usermode_test();
-    for (int i = 0; i < 320; i++) {
-        vga[i] = i;
-    }
-}
-void TestDiskRead() {
-    union V86Regs_t regs;
-    word *vga_text = (word *)0xb8000 + (80*5);
-    vga_text += printStr("Setting Text Mode... ", vga_text);
-    regs.w.ax = 3; // text mode
-    FARPTR v86_entry = i386LinearToFp(v86VideoInt);
-    enter_v86(0x8000, 0xFF00, FP_SEG(v86_entry), FP_OFF(v86_entry), &regs);
-    vga_text += printStr("Done. Starting Disk Read... ", vga_text);
-    v86_entry = i386LinearToFp(v86DiskRead);
-    enter_v86(0x8000, 0xFF00, FP_SEG(v86_entry), FP_OFF(v86_entry), &regs);
-    vga_text = (word *)0xb8000;
-    char *diskReadBuf = (char *)0x23000;
-    for (int i = 0; i < (80*25)/2; i++) {
-        printByte(diskReadBuf[i], &vga_text[i*2]);
-    }
-}
-void TestFAT() {
-    word *vga_text = (word *)0xb8000;
-    uint8_t *diskReadBuf = (uint8_t *)0x22400;
     for (int i = 0; i < 80*25; i++)
-        vga_text[i] = 0x0f00;
+        vga_text[i] = 0x1f00;
+    // draw border
+    for (int c = 1; c < 79; c++) {
+        vga_text[c] = 0x1fc4; // top line
+        vga_text[(2*80)+c] = 0x1fc4; // 3rd line
+        vga_text[(24*80)+c] = 0x1fc4; // bottom line
+    }
+    for (int l = 1; l < 24; l++) {
+        vga_text[80*l] = 0x1fb3;
+        vga_text[(80*l)+79] = 0x1fb3;
+    }
+    vga_text[0] = 0x1fda;
+    vga_text[79] = 0x1fbf;
+    vga_text[2*80] = 0x1fc3;
+    vga_text[2*80+79] = 0x1fb4;
+    vga_text[24*80] = 0x1fc0;
+    vga_text[24*80+79] = 0x1fd9;
+    // name
+    vga_text[80+34] = 0x1f00 | '-';
+    vga_text[80+35] = 0x1f00 | ' ';
+    vga_text[80+36] = 0x1f00 | 'L';
+    vga_text[80+37] = 0x1f00 | 'u';
+    vga_text[80+38] = 0x1f00 | 'c';
+    vga_text[80+39] = 0x1f00 | 'i';
+    vga_text[80+40] = 0x1f00 | 'a';
+    vga_text[80+41] = 0x1f00 | 'O';
+    vga_text[80+42] = 0x1f00 | 'S';
+    vga_text[80+43] = 0x1f00 | ' ';
+    vga_text[80+44] = 0x1f00 | '-';
+}
+
+int32_t fileCount;
+uint16_t *nextLine(uint16_t *p) {
+    uintptr_t v = (uintptr_t)p;
+    return (uint16_t *)(v + (160 - ((v - 0xb8000) % 160)));
+}
+void PrintFileList() {
+    uint16_t *vga_text = &((uint16_t *)0xb8000)[80*4+3];
+    uint8_t *diskReadBuf = (uint8_t *)0x20000;
     VOLINFO vi;
 
     uint8_t pactive, ptype;
     uint32_t pstart, psize;
     pstart = DFS_GetPtnStart(0, diskReadBuf, 0, &pactive, &ptype, &psize);
-    vga_text = (word *)0xb8000;
-    vga_text += printStr("PartStart: ", vga_text);
-    vga_text += printDword(pstart, vga_text);
-    vga_text += 2;
-    vga_text += printStr("PartSize: ", vga_text);
-    vga_text += printDword(psize, vga_text);
-    vga_text += 2;
-    vga_text += printStr("PartActive: ", vga_text);
-    vga_text += printByte(pactive, vga_text);
-    vga_text += 2;
-    vga_text += printStr("PartType: ", vga_text);
-    vga_text += printByte(ptype, vga_text);
-    vga_text = (word *)((((((uintptr_t)vga_text)-0xb8000) - ((((uintptr_t)vga_text)-0xb8000) % 160)) + 160)+0xb8000);
-    //asm ("xchgw %bx, %bx");
 
     DFS_GetVolInfo(0, diskReadBuf, pstart, &vi);
-    vga_text += printStr("Label: ", vga_text);
-    vga_text += printStr((char*)vi.label, vga_text);
-    vga_text += 2;
-    vga_text += printStr("Sec/Clus: ", vga_text);
-    vga_text += printByte(vi.secperclus, vga_text);
-    vga_text += 2;
-    vga_text += printStr("ResrvSec: ", vga_text);
-    vga_text += printWord(vi.reservedsecs, vga_text);
-    vga_text += 2;
-    vga_text += printStr("NumSec: ", vga_text);
-    vga_text += printDword(vi.numsecs, vga_text);
-    vga_text += 2;
-    vga_text += printStr("Sec/FAT: ", vga_text);
-    vga_text += printDword(vi.secperfat, vga_text);
-    vga_text += 2;
-    vga_text += printStr("FAT1@: ", vga_text);
-    vga_text += printDword(vi.fat1, vga_text);
-    vga_text += 2;
-    vga_text += printStr("ROOT@: ", vga_text);
-    vga_text += printDword(vi.rootdir, vga_text);
-    vga_text = (word *)((((((uintptr_t)vga_text)-0xb8000) - ((((uintptr_t)vga_text)-0xb8000) % 160)) + 160)+0xb8000);
-    //asm ("xchgw %bx, %bx");
 
-    vga_text += printStr("Files in root:", vga_text);
     DIRINFO di;
     di.scratch = diskReadBuf;
     DFS_OpenDir(&vi, (uint8_t*)"", &di);
-    vga_text = (word *)((((((uintptr_t)vga_text)-0xb8000) - ((((uintptr_t)vga_text)-0xb8000) % 160)) + 160)+0xb8000);
     DIRENT de;
+    fileCount = 0;
     while (!DFS_GetNext(&vi, &di, &de)) {
         if (de.name[0]) {
             for (int i = 0; i < 11 && de.name[i]; i++) {
@@ -241,9 +207,38 @@ void TestFAT() {
             vga_text += printStr("  ", vga_text);
             vga_text += printDec((uint32_t)de.filesize_0 + ((uint32_t)de.filesize_1 << 8) + ((uint32_t)de.filesize_2 << 16) + ((uint32_t)de.filesize_3 << 24), vga_text);
             *(uint8_t*)vga_text++ = 'B';
-            vga_text = (word *)((((((uintptr_t)vga_text)-0xb8000) - ((((uintptr_t)vga_text)-0xb8000) % 160)) + 160)+0xb8000);
+            vga_text = nextLine(vga_text) + 3;
+            fileCount++;
+        }
+    }
+}
+void FileSelect() {
+    fileCount = 5;
+    uint16_t *vga_text = (uint16_t *)0xb8000;
+    int32_t fileHovered = 0, lastFileHovered = 0;
+    for (;;) {
+        PrintFileList();
+        if (lastFileHovered != fileHovered) {
+            vga_text[80*(4+lastFileHovered)+2] = 0x1f00 | ' ';
+            lastFileHovered = fileHovered;
+        }
+        vga_text[80*(4+fileHovered)+2] = 0x1f00 | '>';
+        uint16_t key = get_scancode();
+        switch (key & 0xff) { // scancode component
+            case 0x50: // down
+                fileHovered++;
+                if (fileHovered >= fileCount) fileHovered = 0;
+                break;
+            case 0x48: // up
+                fileHovered--;
+                if (fileHovered < 0) fileHovered = fileCount - 1;
+                break;
+            case 0x14: // t
+                RunTests(vga_text);
+                DrawScreen();
+            default:
+                break;
         }
-        //asm ("xchgw %bx, %bx");
     }
 }
 
@@ -291,42 +286,14 @@ void start() {
     vga_text++;
     //print_cr3();
     //print_cr4();
-
-    vga_text += printStr("V86 Test... ", vga_text);
-    //asm ("xchgw %bx, %bx");
-    TestV86(); // has int 3 wait in v86
-    vga_text = (word *)0xb8000 + (80*3);
     backup_ivtbios();
-    vga_text += printStr("Done. Press 'N' for next test.", vga_text);
-    uint8_t key;
-    while ((key = get_key()) != 'N') {
-        *vga_text = (*vga_text & 0xFF00) | key;
-        vga_text++;
-    }
-    TestUser();
-    kbd_wait();
-    TestDiskRead();
-    kbd_wait();
-    TestFAT();
-    kbd_wait();
 
-    vga_text = &((uint16_t*)0xB8000)[80*16];
+    vga_text = &((word *)0xb8000)[80];
-    vga_text += printStr("Press E for a flagrant system error. Press C to continue... ", vga_text);
+    vga_text += printStr("Press T for tests, or any key to continue... ", vga_text);
-    for (char l = 1;l;) { switch (key = get_key()) {
+    uint8_t key = get_key();
-        case 'e':
+    if (key == 't' || key == 'T')
-        case 'E':
+        RunTests(vga_text);
-            // flagrant system error
+    DrawScreen();
-            *((uint8_t*)0x1000000) = 0;
+    FileSelect();
-            break;
-        case 'c':
-        case 'C':
-            // continue
-            l = 0;
-            break;
-        default:
-            *vga_text = (*vga_text & 0xFF00) | key;
-            vga_text++;
-            break;
-    }}
 }
 

tests.c

@@ -0,0 +1,152 @@
+#include "tests.h"
+#include "v86defs.h"
+
+extern char *jmp_usermode_test();
+
+void TestV86() {
+    union V86Regs_t regs;
+    regs.d.edi = 0x11111111;
+    regs.d.esi = 0x22222222;
+    regs.d.ebx = 0x33333333;
+    regs.d.edx = 0x44444444;
+    regs.d.ecx = 0x55555555;
+    regs.d.eax = 0x66666666;
+    FARPTR v86_entry = i386LinearToFp(v86Test);
+    enter_v86(0x8000, 0xFF00, FP_SEG(v86_entry), FP_OFF(v86_entry), &regs);
+}
+void TestUser() {
+    char *vga = jmp_usermode_test();
+    for (int i = 0; i < 320; i++) {
+        vga[i] = i;
+    }
+}
+void TestDiskRead() {
+    union V86Regs_t regs;
+    uint16_t *vga_text = (uint16_t *)0xb8000 + (80*5);
+    vga_text += printStr("Setting Text Mode... ", vga_text);
+    regs.w.ax = 3; // text mode
+    FARPTR v86_entry = i386LinearToFp(v86VideoInt);
+    enter_v86(0x8000, 0xFF00, FP_SEG(v86_entry), FP_OFF(v86_entry), &regs);
+    vga_text += printStr("Done. Starting Disk Read... ", vga_text);
+    char *diskReadBuf = (char *)0x23000;
+	v86disk_addr_packet.transfer_buffer =
+		(uintptr_t)diskReadBuf & 0x000F |
+		(((uintptr_t)diskReadBuf & 0xFFFF0) << 12);
+    v86_entry = i386LinearToFp(v86DiskRead);
+    enter_v86(0x8000, 0xFF00, FP_SEG(v86_entry), FP_OFF(v86_entry), &regs);
+    vga_text = (uint16_t *)0xb8000;
+    for (int i = 0; i < (80*25)/2; i++) {
+        printByte(diskReadBuf[i], &vga_text[i*2]);
+    }
+}
+void TestFAT() {
+    uint16_t *vga_text = (uint16_t *)0xb8000;
+    uint8_t *diskReadBuf = (uint8_t *)0x22400;
+    for (int i = 0; i < 80*25; i++)
+        vga_text[i] = 0x0f00;
+    VOLINFO vi;
+
+    uint8_t pactive, ptype;
+    uint32_t pstart, psize;
+    pstart = DFS_GetPtnStart(0, diskReadBuf, 0, &pactive, &ptype, &psize);
+    vga_text = (uint16_t *)0xb8000;
+    vga_text += printStr("PartStart: ", vga_text);
+    vga_text += printDword(pstart, vga_text);
+    vga_text += 2;
+    vga_text += printStr("PartSize: ", vga_text);
+    vga_text += printDword(psize, vga_text);
+    vga_text += 2;
+    vga_text += printStr("PartActive: ", vga_text);
+    vga_text += printByte(pactive, vga_text);
+    vga_text += 2;
+    vga_text += printStr("PartType: ", vga_text);
+    vga_text += printByte(ptype, vga_text);
+    vga_text = (uint16_t *)((((((uintptr_t)vga_text)-0xb8000) - ((((uintptr_t)vga_text)-0xb8000) % 160)) + 160)+0xb8000);
+    //asm ("xchgw %bx, %bx");
+
+    DFS_GetVolInfo(0, diskReadBuf, pstart, &vi);
+    vga_text += printStr("Label: ", vga_text);
+    vga_text += printStr((char*)vi.label, vga_text);
+    vga_text += 2;
+    vga_text += printStr("Sec/Clus: ", vga_text);
+    vga_text += printByte(vi.secperclus, vga_text);
+    vga_text += 2;
+    vga_text += printStr("ResrvSec: ", vga_text);
+    vga_text += printWord(vi.reservedsecs, vga_text);
+    vga_text += 2;
+    vga_text += printStr("NumSec: ", vga_text);
+    vga_text += printDword(vi.numsecs, vga_text);
+    vga_text += 2;
+    vga_text += printStr("Sec/FAT: ", vga_text);
+    vga_text += printDword(vi.secperfat, vga_text);
+    vga_text += 2;
+    vga_text += printStr("FAT1@: ", vga_text);
+    vga_text += printDword(vi.fat1, vga_text);
+    vga_text += 2;
+    vga_text += printStr("ROOT@: ", vga_text);
+    vga_text += printDword(vi.rootdir, vga_text);
+    vga_text = (uint16_t *)((((((uintptr_t)vga_text)-0xb8000) - ((((uintptr_t)vga_text)-0xb8000) % 160)) + 160)+0xb8000);
+    //asm ("xchgw %bx, %bx");
+
+    vga_text += printStr("Files in root:", vga_text);
+    DIRINFO di;
+    di.scratch = diskReadBuf;
+    DFS_OpenDir(&vi, (uint8_t*)"", &di);
+    vga_text = (uint16_t *)((((((uintptr_t)vga_text)-0xb8000) - ((((uintptr_t)vga_text)-0xb8000) % 160)) + 160)+0xb8000);
+    DIRENT de;
+    while (!DFS_GetNext(&vi, &di, &de)) {
+        if (de.name[0]) {
+            for (int i = 0; i < 11 && de.name[i]; i++) {
+                if (i == 8) { *(uint8_t*)vga_text = ' '; vga_text++; } // space for 8.3
+                *(uint8_t *)vga_text = de.name[i];
+                vga_text++;
+            }
+            vga_text += printStr("  ", vga_text);
+            vga_text += printDec((uint32_t)de.filesize_0 + ((uint32_t)de.filesize_1 << 8) + ((uint32_t)de.filesize_2 << 16) + ((uint32_t)de.filesize_3 << 24), vga_text);
+            *(uint8_t*)vga_text++ = 'B';
+            vga_text = (uint16_t *)((((((uintptr_t)vga_text)-0xb8000) - ((((uintptr_t)vga_text)-0xb8000) % 160)) + 160)+0xb8000);
+        }
+        //asm ("xchgw %bx, %bx");
+    }
+}
+
+void RunTests(uint16_t *vga_text) {
+    uint8_t key;
+    vga_text += printStr("V86 Test... ", vga_text);
+    //asm ("xchgw %bx, %bx");
+    TestV86(); // has int 3 wait in v86
+    vga_text = (uint16_t *)0xb8000 + (80*3);
+    vga_text += printStr("Done. Press 'N' for next test.", vga_text);
+    while ((key = get_key()) != 'N') {
+        *vga_text = (*vga_text & 0xFF00) | key;
+        vga_text++;
+    }
+    TestUser();
+    kbd_wait();
+    TestDiskRead();
+    kbd_wait();
+    TestFAT();
+    kbd_wait();
+    TestFAT();
+    kbd_wait();
+
+    vga_text = &((uint16_t*)0xB8000)[80*16];
+    vga_text += printStr("Press E for a flagrant system error. Press C to continue... ", vga_text);
+    for (char l = 1;l;) { switch (key = get_key()) {
+        case 'e':
+        case 'E':
+            // flagrant system error
+            *((uint8_t*)0x1000000) = 0;
+            break;
+        case 'c':
+        case 'C':
+            // continue
+            l = 0;
+            break;
+        default:
+            *vga_text = (*vga_text & 0xFF00) | key;
+            vga_text++;
+            break;
+    }}
+}
+

tests.h

@@ -0,0 +1,6 @@
+#include "dosfs/dosfs.h"
+#include "print.h"
+#include "interrupt.h"
+#include "v86defs.h"
+
+void RunTests(uint16_t *vga_text);

v86defs.h

@@ -1,3 +1,4 @@
+#pragma once
 #include <stdint.h>
 
 extern void v86Test();