Done a bunch of stuff

Makefile

@@ -1,7 +1,7 @@
 ASM=nasm
 CC=gcc
-CC16=/usr/bin/watcom/binl/wcc
-LD16=/usr/bin/watcom/binl/wlink
+CC16=/opt/watcom/binl/wcc
+LD16=/opt/watcom/binl/wlink
 
 SRC_DIR=src
 TOOLS_DIR=tools
@@ -22,7 +22,7 @@ $(BUILD_DIR)/main_floppy.img: bootloader kernel
 	dd if=$(BUILD_DIR)/stage1.bin of=$(BUILD_DIR)/main_floppy.img conv=notrunc
 	mcopy -i $(BUILD_DIR)/main_floppy.img $(BUILD_DIR)/stage2.bin "::stage2.bin"
 	mcopy -i $(BUILD_DIR)/main_floppy.img $(BUILD_DIR)/kernel.bin "::kernel.bin"
-	mcopy -i $(BUILD_DIR)/main_floppy.img readme.txt "::readme.txt"
+	mcopy -i $(BUILD_DIR)/main_floppy.img test.txt "::test.txt"
 
 #
 # Bootloader

src/bootloader/stage1/boot.asm

@@ -367,7 +367,7 @@ disk_reset:
     ret
 
 
-msg_loading:			db 'Starting Nanite 0.0.1a...', ENDL, 0
+msg_loading:			db 'Loading Nanite...', ENDL, 0
 msg_read_failed:		db 'Cant Read Disk!', ENDL, 0	
 msg_no_stage2:			db 'Cant Find Stage 2!', ENDL, 0	
 file_stage2_bin:		db 'STAGE2  BIN'

src/bootloader/stage2/Makefile

@@ -1,9 +1,9 @@
 BUILD_DIR?=build/
 ASM?=nasm
 ASMFLAGS?=-f obj
-CC16?=/usr/bin/watcom/binl/wcc
-CFLAGS16?=-4 -d3 -s -wx -ms -zl -zq # -oneatxzh 
-LD16?=/usr/bin/watcom/binl/wlink
+CC16?=/opt/watcom/binl/wcc
+CFLAGS16?=-4 -d3 -s -wx -ms -zl -zq -za99 # -oneatxzh 
+LD16?=/opt/watcom/binl/wlink
 
 SOURCES_C=$(wildcard *.c)
 SOURCES_ASM=$(wildcard *.asm)

src/bootloader/stage2/disk.c

@@ -0,0 +1,43 @@
+#include "disk.h"
+#include "x86.h"
+#include "stdio.h"
+
+bool DISK_Initialize(DISK* disk, uint8_t driveNumber) {
+    uint8_t driveType;
+    uint16_t cylinders, sectors, heads;
+    
+    if (!x86_Disk_GetDriveParams(disk->id, &driveType, &cylinders, &sectors, &heads))
+        return false;
+
+    disk->id = driveNumber;
+    disk->cylinders = cylinders;
+    disk->heads = heads;
+    disk->sectors = sectors;
+
+    return true;
+}
+
+void DISK_LBA2CHS(DISK* disk, uint32_t lba, uint16_t* cylinderOut, uint16_t* sectorOut, uint16_t* headOut) {
+    // sector = (LBA % sectors per track + 1)
+    *sectorOut = lba % disk->sectors +1;
+
+    // cylinder = (LBA / sects per track / heads)
+    *cylinderOut = (lba / disk->sectors) / disk->heads;
+
+    // head = (LBA / sects per track % heads)
+    *headOut = (lba / disk->sectors) % disk->heads;
+}
+
+bool DISK_ReadSectors(DISK* disk, uint32_t lba, uint8_t sectors, void far* dataOut) {
+    uint16_t cylinder, sector, head;
+
+    DISK_LBA2CHS(disk, lba, &cylinder, &sector, &head);
+
+    for (int i = 0; i < 3; i++) {
+        if (x86_Disk_Read(disk->id, cylinder, sector, head, sectors, dataOut))
+            return true;
+        x86_Disk_Reset(disk->id);
+    }
+
+    return false;
+}

src/bootloader/stage2/disk.h

@@ -12,8 +12,8 @@ typedef struct {
     uint16_t cylinders;
     uint16_t sectors;
     uint16_t heads;
-};
+} DISK;
 
 bool DISK_Initialize(DISK* disk, uint8_t driveNumber);
-bool DISK_ReadSectors(DISK* disk, uint32_t lba, uint8_t far* dataOut);
+bool DISK_ReadSectors(DISK* disk, uint32_t lba, uint8_t sectors, void far* dataOut);
 

src/bootloader/stage2/fat.c

@@ -0,0 +1,201 @@
+#include "fat.h"
+#include "stdio.h"
+#include "memdefs.h"
+#include "utility.h"
+
+#define SECTOR_SIZE 512
+
+#pragma pack(push,1)
+typedef struct
+{
+	uint8_t BootJumpInstruction[3];
+	uint8_t OemIdentifier[8];
+	uint16_t BytesPerSector;
+	uint8_t SectorsPerCluster;
+	uint16_t ReservedSectors;
+	uint8_t FatCount;
+	uint16_t DirEntryCount;
+	uint16_t TotalSectors;
+	uint8_t MediaDescriptorType;
+	uint16_t SectorsPerFat;
+	uint16_t SectorsPerTrack;
+	uint16_t Heads;
+	uint32_t HiddenSectors;
+	uint32_t LargeSectorCount;
+	
+//Extended Boot Record
+	uint8_t DriveNumber;
+	uint8_t _Reserved;
+	uint8_t Signature;
+	uint32_t VolumeId;			//Serial Can be whatever
+	uint8_t VolumeLabel[11];		//11 Bytes MUST Be padded with spaces!
+	uint8_t SystemId[8];		//8 Bytes padded with spaces (use MSWIN4.1 for best compatibility!)
+	
+} FAT_BootSector;
+#pragma pack(pop)
+
+typedef struct {
+	union {
+		FAT_BootSector Bootsector;
+		uint8_t BootsectorBytes[SECTOR_SIZE];
+	} BS;
+
+} FAT_Data;
+
+static FAT_Data far* g_Data;
+static uint8_t far* g_Fat = NULL;
+static FAT_DirectoryEntry far* g_RootDirectory = NULL;
+static uint32_t g_RootDirectoryEnd;
+
+bool FAT_ReadBootSector(FILE* disk) {
+ 	return DISK_ReadSectors(disk, 0, 1, &g_Data->BS.BootSectorBytes);
+}
+
+bool FAT_ReadFat(DISK* disk)
+{
+	return DISK_ReadSectors(disk, g_Data->g_BootSector.ReservedSectors, g_Data->g_BootSector.SectorsPerFat, g_Fat);
+}
+
+bool FAT_ReadRootDirectory(DISK* disk)
+{
+	uint32_t lba = g_Data->g_BootSector.ReservedSectors + g_Data->g_BootSector.SectorsPerFat * g_Data->g_BootSector.FatCount;
+	uint32_t size = sizeof(FAT_DirectoryEntry) * g_Data->g_BootSector.DirEntryCount;
+	uint32_t sectors = (size + g_Data->g_BootSector.BytesPerSector - 1) / g_Data->g_BootSector.BytesPerSector;
+		
+	g_RootDirectoryEnd = lba + sectors;
+	return DISK_ReadSectors(disk, lba, sectors, g_RootDirectory);
+}
+
+bool FAT_Initialize(DISK* disk) {
+	g_Data = (FAT_Data far*)MEMORY_FAT_ADDR;
+
+	// read bootsector
+	if (!FAT_ReadBootSector(disk)) {
+		printf("FAT: Bootsector Read Failed!\r\n");
+		return false;
+	}
+
+	// read FAT
+	g_Fat = (uint8_t far*)(g_Data + sizeof(FAT_Data));
+	uint32_t fatSize = g_Data->BS.Bootsector.BytesPerSector * g_Data->BS.BootSector.SectorsPerFat;
+	if(sizeof(FAT_Data) + fatSize >= MEMORY_FAT_SIZE) {
+		printf("FAT: Not Enough Memory to Read FAT!\r\nNeeded %u, Only Have %u\r\n", sizeof(FAT_Data) + fatSize, MEMORY_FAT_SIZE);
+		return false;
+	}
+
+	if (!FAT_ReadFat(disk)) {
+		printf("FAT: Failed to Read FAT!\r\n");
+		return false;
+	}
+	// read root dir (/)
+	g_RootDirectory = (FAT_DirectoryEntry far*)(g_Fat + fatSize);
+	uint32_t rootDirSize = sizeof(FAT_DirectoryEntry) * g_Data->BS.BootSector.DirEntryCount;
+	rootDirSize = align(rootDirSize, g_Data->BS.BootSector.BytesPerSector);
+
+	if (sizeof(FAT_Data) + fatSize + rootDirSize >= MEMORY_FAT_SIZE) { 
+		printf("FAT: Not Enough Memory to Read Root Directory!\r\nNeeded %u, Only Have %u\r\n", sizeof(FAT_Data) + fatSize + rootDirSize, MEMORY_FAT_SIZE);
+		return false;	
+	}
+
+	if(!FAT_ReadRootDirectory(disk)) { 
+		printf("FAT: Failed to Read Root Directory!\r\n");
+		return false;
+	}
+}
+
+FAT_File far* FAT_Open(DISK* disk, const char* path) { 
+	
+}
+
+DirectoryEntry* findFile(const char* name)
+{
+	for (uint32_t i = 0; i < g_BootSector.DirEntryCount; i++)
+	{
+		if (memcmp(name, g_RootDirectory[i].Name, 11) == 0)
+		return &g_RootDirectory[i];
+		
+	}
+
+	return NULL;
+}
+
+bool readFile(DirectoryEntry* fileEntry, FILE* disk, uint8_t* outputBuffer)
+{
+	bool ok = true;
+	uint16_t currentCluster = fileEntry->FirstClusterLow;
+
+	do {
+		uint32_t lba = g_RootDirectoryEnd + (currentCluster - 2) * g_BootSector.SectorsPerCluster;
+		ok = ok && readSectors(disk, lba, g_BootSector.SectorsPerCluster, outputBuffer);
+		outputBuffer += g_BootSector.SectorsPerCluster * g_BootSector.BytesPerSector;
+
+		uint32_t fatIndex = currentCluster * 3 / 2;
+		if (currentCluster % 2 == 0)
+			currentCluster = (*(uint16_t*)(g_Fat + fatIndex)) & 0x0FFF;
+		else
+			currentCluster = (*(uint16_t*)(g_Fat + fatIndex)) >> 4;
+			
+	} while (ok && currentCluster < 0x0FF8);
+
+	return ok;
+}
+
+int main(int argc, char** argv)
+{
+	if (argc < 3){
+		printf("Syntax: %s <disk image> <file name>\n", argv[0]);
+		return -1;
+	}
+
+	FILE* disk = fopen(argv[1], "rb");
+	if (!disk) {
+		fprintf(stderr, "Cannot open disk image %s!\n", argv[1]);
+		return -1;
+	}
+
+	if (!readBootSector(disk)) {
+		fprintf(stderr, "Could not read boot sector!\n");
+		return -2;
+	}
+
+	if (!readFat(disk)) {
+		fprintf(stderr, "Could not read FAT!\n");
+		free(g_Fat);
+		return -3;
+	}
+
+	if (!readRootDirectory(disk)) {
+		fprintf(stderr, "Could not read root!\n");
+		free(g_Fat);
+		free(g_RootDirectory);
+		return -4;
+	}
+
+	DirectoryEntry* fileEntry = findFile(argv[2]);
+	if (!fileEntry) {
+		fprintf(stderr, "Could not locate file %s!\n", argv[2]);
+		free(g_Fat);
+		free(g_RootDirectory);
+		return -5;
+	}
+
+	uint8_t* buffer = (uint8_t*) malloc(fileEntry->Size + g_BootSector.BytesPerSector);
+	if (!readFile(fileEntry, disk, buffer)) {
+		fprintf(stderr, "Could not read file %s!\n", argv[2]);
+		free(g_Fat);
+		free(g_RootDirectory);
+		free(buffer);
+		return -5;
+	}
+
+	for (size_t i = 0; i < fileEntry->Size; i++)
+	{
+		if (isprint(buffer[i])) fputc(buffer[i], stdout);
+		//else printf("<%02x>", buffer[i]);
+	}
+	printf("\n");
+	
+	free(g_Fat);
+	free(g_RootDirectory);
+	return 0;
+}

src/bootloader/stage2/fat.h

@@ -0,0 +1,47 @@
+#pragma once
+#include "stdint.h"
+#include "disk.h"
+
+#pragma pack(push, 1)
+typedef struct
+{
+	uint8_t Name[11];
+	uint8_t Attributes;
+	uint8_t _Reserved;
+	uint8_t CreatedTimeTenths;
+	uint16_t CreatedTime;
+	uint16_t CreatedDate;
+	uint16_t AccessedDate;
+	uint16_t FirstClusterHigh;
+	uint16_t ModifiedTime;
+	uint16_t ModifiedDate;
+	uint16_t FirstClusterLow;
+	uint32_t Size;
+	
+} FAT_DirectoryEntry;
+#pragma pack(pop)
+
+typdef struct {
+    int Handle;
+    bool IsDirectory;
+    uint32_t Position;
+    uint32_t Size;
+} FAT_File;
+
+enum FAT_Attributes {
+    FAT_ATTRIBUTE_READ_ONLY         = 0x01,
+    FAT_ATTRIBUTE_HIDDEN            = 0x02,
+    FAT_ATTRIBUTE_SYSTEM            = 0x04,
+    FAT_ATTRIBUTE_VOLUME_ID         = 0x08,
+    FAT_ATTRIBUTE_DIRECTORY         = 0x10,
+    FAT_ATTRIBUTE_ARCHIVE           = 0x20,
+    FAT_ATTRIBUTE_LFN               = FAT_ATTRIBUTE_READ_ONLY | FAT_ATTRIBUTE_HIDDEN | FAT_ATTRIBUTE_SYSTEM | FAT_ATTRIBUTE_VOLUME_ID
+};
+
+
+
+bool FAT_Initialize(DISK* disk);
+FAT_File far* FAT_Open(DISK* disk, const char* path);
+uint32_t FAT_Read(DISK* disk, FAT_File far* file, uint32_t byteCount, void* dataOut);
+bool FAT_ReadEntry(DISK* disk, FAT_File far* file, FAT_DirectoryEntry* dirEntry);
+void FAT_Close(FAT_File far* file);

src/bootloader/stage2/main.c

@@ -6,8 +6,7 @@
 #include "stdint.h"
 #include "stdio.h"
 
-void _cdecl cstart_(uint16_t bootDrive)
-{
-    puts("Going from x86 ASM to C code!\r\n");
-    printf("Initialized!\r\n");
+void _cdecl cstart_(uint16_t bootDrive) {
+    puts("Loading Main System\r\n");
+    printf("Done!\r\n");
 }

src/bootloader/stage2/main.err

@@ -1 +0,0 @@
-main.c(9): Warning! W303: Parameter 'bootDrive' has been defined, but not referenced

src/bootloader/stage2/memdefs.h

@@ -0,0 +1,19 @@
+#pragma once
+
+// 0x00000000 - 0x000003FF - int vector table
+// 0x00000400 - 0x000004FF - Bios Data
+
+#define MEMORY_MIN          0x00000500
+#define MEMORY_MAX          0x00080000
+
+// 0x00000500 - 0x00010500 - FAT Driver
+#define MEMORY_FAT_ADDR     ((void far*)0x00500000) // segment:offset SSSS:OOOO
+#define MEMORY_FAT_SIZE     0x00010500
+
+// 0x00020000 - 0x00030000 - stage2
+
+// 0x00030000 - 0x00080000 - free
+
+// 0x00080000 - 0x0009FFFF - Extended BIOS data area
+// 0x000A0000 - 0x000C7FFF - Video
+// 0x000C8000 - 0x000FFFFF - BIOS

src/bootloader/stage2/stdint.h

@@ -18,3 +18,5 @@ typedef uint8_t bool;
 
 #define true 1
 #define false 0
+
+#define NULL ((void*)0)

src/bootloader/stage2/stdio.err

@@ -1,5 +0,0 @@
-x86.h(22): Error! E1009: Expecting ',' or ';' but found 'x86_Disk_GetDriveParams'
-stdio.c(100): Warning! W100: Parameter 1 contains inconsistent levels of indirection
-stdio.c(100): Note! I2003: source conversion type is 'char **'
-stdio.c(100): Note! I2004: target conversion type is 'char const *'
-stdio.c(100): Note! I2002: 'puts' defined in: stdio.c(14)

src/bootloader/stage2/string.c

@@ -0,0 +1,36 @@
+#include "string.h"
+#include "stdint.h"
+
+const char* strchr(const char* str, char chr) { 
+    if (str == NULL)
+        return NULL;
+
+    while (*str) {
+        if (*str == chr)
+            return str;
+
+        ++str;
+    }
+
+    return NULL;
+}
+
+char* strcpy(char* dst, const char* src) {
+    char* origDst = dst;
+    
+    if (dst == NULL)
+        return NULL;
+    
+    if (src == NULL) {
+        *dst = '\0';
+        return dst;
+    }
+    while (*src) { 
+        *dst = *src;
+        ++src;
+        ++dst;
+    }
+
+    *dst = '\0'; 
+    return origDst;
+}

src/bootloader/stage2/string.h

@@ -0,0 +1,4 @@
+#pragma once
+
+const char* strchr(const char* str, char chr);
+char* strcpy(char* dst, const char* src);

src/bootloader/stage2/utility.c

@@ -0,0 +1,9 @@
+#include "utility.h"
+
+uint32_t align(uint32_t number, uint32_t alignTo) { 
+    if (alignTo == 0)
+        return number;
+
+    uint32_t rem = number % alignTo;
+    return (rem > 0) ? (number + alignTo - rem) : number;
+}

src/bootloader/stage2/utility.h

@@ -0,0 +1,4 @@
+#pragma once
+#include "stdint.h"
+
+uint32_t align(uint32_t number, uint32_t alignTo);

src/bootloader/stage2/x86.asm

@@ -7,12 +7,42 @@ bits 16
 
 section _TEXT class=CODE
 
+;
+; U4D
+;
+; Operation:      Unsigned 4 byte divide
+; Inputs:         DX;AX   Dividend
+;                 CX;BX   Divisor
+; Outputs:        DX;AX   Quotient
+;                 CX;BX   Remainder
+; Volatile:       none
+;
+global __U4D
+__U4D:
+    shl edx, 16         ; dx to upper half of edx
+    mov dx, ax          ; edx - dividend
+    mov eax, edx        ; eax - dividend
+    xor edx, edx
+
+    shl ecx, 16         ; cx to upper half of ecx
+    mov cx, bx          ; ecx - divisor
+
+    div ecx             ; eax - quot, edx - remainder
+    mov ebx, edx
+    mov ecx, edx
+    shr ecx, 16
+
+    mov edx, eax
+    shr edx, 16
+
+    ret
+
 ;
 ;void _cdecl x86_div64_32(uint64_t dividend, uint32_t divisor, uint64_t* quotentOut, uint32_t* remainderOut);
 ;
 
 global _x86_div64_32
-_x86_div64_32
+_x86_div64_32:
 	;make new call frame
 	push bp			;save old call frame
 	mov bp, sp		;init new call frame
@@ -71,7 +101,7 @@ _x86_Video_WriteCharTeletype:
 
 
 ;
-;void _cdecl x86_Disk_Reset(uint8_t drive);
+; bool _cdecl x86_Disk_Reset(uint8_t drive);
 ;
 global _x86_Disk_Reset
 _x86_Disk_Reset:
@@ -79,7 +109,13 @@ _x86_Disk_Reset:
 	push bp			;save old call frame
 	mov bp, sp		;init new call frame
 
-	
+	mov ah, 0
+	mov dl, [bp + 4]; dl - drive
+	std
+	int 13h
+
+	mov ax, 1
+	sbb ax, 0		; 1 is true 0 is false
 
 	;restore old call frame
 	mov sp, bp
@@ -88,15 +124,108 @@ _x86_Disk_Reset:
 
 
 ;
-;void _cdecl x86_Disk_Read(uint8_t drive,
+; bool _cdecl x86_Disk_Read(uint8_t drive,
 ;						  uint16_t cylinder,
 ;						  uint16_t head,
 ;						  uint16_t sector,
 ;						  uint8_t count,
 ;						  uint8_t far * dataout);
 ;
-;void _cdelc x86_Disk_GetDriveParams(uint8_t drive,
+global _x86_Disk_Read
+_x86_Disk_Read:
+	;make new call frame
+	push bp			;save old call frame
+	mov bp, sp		;init new call frame
+
+	;setup args
+	mov dl, [bp + 4]; dl - drive
+
+	mov ch, [bp + 6]; ch - cylinder (lower 8 bits)
+	mov cl, [bp + 7]; cl - cylinder to to bits 6-7
+	shl cl, 6
+
+	mov dh, [bp + 10]; dh - head
+
+	mov al, [bp + 8]; cl - sectory to bits 0-5
+	and al, 3Fh
+	or cl, al		
+
+	mov al, [bp + 12]; count
+
+	mov bx, [bp + 16]; es:bx - far pointer to data out
+	mov es, bx
+	mov bx, [bp + 14]
+
+	; call
+	mov al, 02h
+	std
+	int 13h
+
+	mov ax, 1
+	sbb ax, 0		; 1 is true 0 is false
+
+	; restore old call frame
+	mov sp, bp
+	pop bp
+	ret
+
+
+
+; bool _cdelc x86_Disk_GetDriveParams(uint8_t drive,
 ;									uint8_t* driveTypeOut,
 ;									uint16_t* cylindersOut,
 ;									uint16_t* sectorsOut,
 ;									uint16_t* headsOut);
+global _x86_Disk_GetDriveParams
+_x86_Disk_GetDriveParams:
+	; make new call frame
+	push bp				; save old frame
+	mov bp, sp			; init new frame
+
+	; save regs
+	push es
+	push bx
+	push si
+	push di
+
+	; call int13h
+	mov dl, [bp + 4]	;dl - drive
+	mov ah, 08h
+	mov di, 0			;es:di - 0000:0000
+	mov es, di
+	stc
+	int 13h
+
+	; return
+	mov ax, 1
+	sbb ax, 0
+
+	; out params
+	mov si, [bp + 6]	; drive type
+	mov [si], bl
+
+	mov bl, ch			; cyl - lower bits in ch
+	mov bh, cl			; cyl - upper bits in ch (6-7)
+	shr bh, 6
+	mov si, [bp + 8]
+	mov [si], bx
+
+	xor ch, ch			; sectors - lower 5 bits of cl
+	and cl, 3Fh
+	mov si, [bp + 10]
+	mov [si], cx
+
+	mov cl, dh
+	mov si, [bp + 12]
+	mov [si], cx
+
+	; restore regs
+	pop di
+	pop si
+	pop bx
+	pop es
+
+	; restore old call frame
+	mov sp, bp
+	pop bp
+	ret

src/bootloader/stage2/x86.h

@@ -10,16 +10,16 @@ void _cdecl x86_div64_32(uint64_t dividend, uint32_t divisor, uint64_t* quotentO
 
 void _cdecl x86_Video_WriteCharTeletype(char c, uint8_t page);
 
-void _cdecl x86_Disk_Reset(uint8_t drive);
+bool _cdecl x86_Disk_Reset(uint8_t drive);
 
-void _cdecl x86_Disk_Read(uint8_t drive,
+bool _cdecl x86_Disk_Read(uint8_t drive,
                           uint16_t cylinder,
-                          uint16_t head,
                           uint16_t sector,
+                          uint16_t head,
                           uint8_t count,
-                          uint8_t far * dataout);
+                          void far * dataout);
 
-void _cdelc x86_Disk_GetDriveParams(uint8_t drive,
+bool _cdecl x86_Disk_GetDriveParams(uint8_t drive,
                                     uint8_t* driveTypeOut,
                                     uint16_t* cylindersOut,
                                     uint16_t* sectorsOut,

test.txt

@@ -0,0 +1 @@
+this is text test har har har har *insert meme here* har har har