Give up on RYOB, use mb instead

Makefile

@@ -0,0 +1,54 @@
+ASM ?= nasm
+CC := i686-elf-gcc
+GDB := i686-elf-gdb
+LD := i686-elf-ld
+
+C_FILES = $(shell find src/ -type f -name '*.c')
+CO_FILES = $(patsubst src/%.c, obj/%.o, $(C_FILES))
+ASM_FILES = $(shell find src/kernel/ -type f -name '*.asm')
+AO_FILES = $(patsubst src/kernel/%.asm, obj/kernel/%.o, $(ASM_FILES))
+
+KERNEL_O_FILES = ${CO_FILES} ${AO_FILES}
+
+iso: bin/shade.iso
+
+obj/boot.o: src/boot.asm
+	$(ASM) -felf32 $^ -o $@
+
+bin/shade.bin: obj/boot.o ${KERNEL_O_FILES}
+	mkdir -p bin
+	$(CC) -T src/linker.ld -ffreestanding -O2 -nostdlib $^ -o $@ -lgcc
+	grub-file --is-x86-multiboot bin/shade.bin
+
+bin/shade.iso: bin/shade.bin
+	mkdir -p isodir/boot/grub
+	cp bin/shade.bin isodir/boot/shade.bin
+	cp src/iso/grub.cfg isodir/boot/grub/grub.cfg
+	grub-mkrescue -o bin/shade.iso isodir
+	rm -rf isodir
+
+obj/%.o: src/%.c
+	mkdir -p "$(@D)"
+	$(CC) -ffreestanding -O2 -Wall -Wextra -c $< -o $@
+
+obj/%.o: src/%.asm
+	mkdir -p "$(@D)"
+	$(ASM) -f elf $< -o $@
+
+
+run: clean bin/shade.iso
+	qemu-system-x86_64 -hdd bin/shade.iso
+
+debug: clean bin/shade.iso bin/shade.bin
+	qemu-system-x86_64 -s -S -hdd bin/shade.iso &
+	${GDB} os-image.bin -ex "symbol-file bin/shade.bin" -ex "target remote localhost:1234"
+
+
+clean:
+	find obj -type f -name '*.o' -exec rm {} +
+	find obj -type f -name '*.bin' -exec rm {} +
+	find bin -type f -name '*.o' -exec rm {} +
+	find bin -type f -name '*.bin' -exec rm {} +
+	find . -type f -name '*.dis' -exec rm {} +
+	rm -f kernel.elf
+	rm -rf isodir

src/boot.asm

@@ -0,0 +1,38 @@
+; Declare constants for the multiboot header.
+MBALIGN  equ  1 << 0            ; align loaded modules on page boundaries
+MEMINFO  equ  1 << 1            ; provide memory map
+FLAGS    equ  MBALIGN | MEMINFO ; this is the Multiboot 'flag' field
+MAGIC    equ  0x1BADB002        ; 'magic number' lets bootloader find the header
+CHECKSUM equ -(MAGIC + FLAGS)   ; checksum of above, to prove we are multiboot
+
+section .multiboot
+align 4
+    dd MAGIC
+	dd FLAGS
+	dd CHECKSUM
+
+section .bss
+align 16
+
+stack_bottom:
+resb 16384
+stack_top:
+
+; _start = entry to kernel
+; Since the bootloader will be gone, it doesn't make sense to return from this
+section .text
+
+global _start:function (_start.end - _start)
+_start:
+    ; 32bit protected mode, no int, no paging
+    mov esp, stack_top ; Initialize stack
+
+    extern kmain
+    call kmain
+
+    cli ; Turn off interrupts in case they are on
+.hang:
+    hlt ; Totally halt the cpu
+    jmp .hang ; If the cpu un-halts for some reason, halt again
+
+.end:

src/iso/grub.cfg

@@ -0,0 +1,3 @@
+menuentry "shadeOS Dev Build" {
+    multiboot /boot/shade.bin
+}

src/kernel/kernel.c

@@ -0,0 +1,55 @@
+#include "./platform/drivers/ports.h"
+#include "print.h"
+#include "./platform/types.h"
+//#include "./platform/interrupts/int.h"
+
+void dummy_test_entrypoint() {}
+
+void kernel_welcome() {
+    print_str("Welcome to ");
+    print_set_color(PRINT_COLOR_CYAN, PRINT_COLOR_BLACK);
+    print_str("Shade");
+	print_set_color(PRINT_COLOR_WHITE, PRINT_COLOR_BLACK);
+    print_str("!\n");
+	
+	print_str("shadeOS kernel version ");
+	
+	print_set_color(PRINT_COLOR_YELLOW, PRINT_COLOR_BLACK);
+	print_str("0.2.2");
+	
+	print_set_color(PRINT_COLOR_WHITE, PRINT_COLOR_BLACK);
+	print_newline();
+	
+	print_str("Running on ");
+	
+	print_set_color(PRINT_COLOR_YELLOW, PRINT_COLOR_BLACK);
+	print_str("shade-development");
+
+    print_set_color(PRINT_COLOR_WHITE, PRINT_COLOR_BLACK);
+	
+	print_newline();
+}
+
+// kMain
+void kmain() {
+    // Initialize screen buffer
+	struct Char* buffer = (struct Char*) 0xb8000;
+    
+    clear_all(); // Clear screen
+    set_cursor_pos(0, 0); // Set cursor position
+    print_set_color(PRINT_COLOR_WHITE, PRINT_COLOR_BLACK); // Set print color
+
+    // welcome messages
+    kernel_msg_ok("Initialized display successfully\n");
+    kernel_welcome();
+
+    print_str("Copyright (c) e3team 2022. All rights reserved.\n");
+    print_str("This program is provided \"as-is\" and no express or implied warranty is provided.\n");
+    print_str("The full license can be found at /sys/LICENCE on this system or ./LICENCE in the source tree.\n");
+/*
+    idt_init();
+    kernel_msg_ok("Interrupts initialized");
+
+    __asm__ __volatile__("int $2");
+*/
+}

src/kernel/platform/drivers/ports.c

@@ -0,0 +1,26 @@
+/*
+ * Read 1 byte from specified port
+ */
+unsigned char port_byte_in(unsigned short port) {
+    unsigned char result;
+    // source and dest are backwards.
+    // "=a (result)" set the C variable to the value of register e'a'x
+    // '"d" (port) map the C variable port into e'd'x register
+    __asm__("in %%dx, %%al" : "=a" (result) : "d" (port));
+}
+
+void port_byte_out(unsigned short port, unsigned char data) {
+    // both regs are C vars, nothing is returned, so no '=' in asm syntax
+    // comma because two vars in input area and none in return area
+    __asm__("out %%al, %%dx" : : "a" (data), "d" (port));
+}
+
+unsigned short port_word_in(unsigned short port) {
+    unsigned short result;
+    __asm__("in %%dx, %%ax" : "=a" (result) : "d" (port));
+    return result;
+}
+
+void port_word_out(unsigned short port, unsigned short data) {
+    __asm__("out %%ax, %%dx" : : "a" (data), "d" (port));
+}

src/kernel/platform/drivers/ports.h

@@ -0,0 +1,4 @@
+unsigned char port_byte_in(unsigned short port);
+void port_byte_out(unsigned short port, unsigned char data);
+unsigned short port_word_in(unsigned short port);
+void port_word_out(unsigned short port, unsigned short data);

src/kernel/platform/types.h

@@ -0,0 +1,18 @@
+#ifndef TYPES_H
+#define TYPES_H
+
+typedef unsigned int   u32;
+typedef          int   i32;
+typedef unsigned short u16;
+typedef          short i16;
+typedef unsigned char  u8;
+typedef          char  i8;
+
+#define high16(i32) (i32 & 0xffff)
+#define low16(i32) ((i32>>16) & 0xffff)
+
+#define TRUE 1
+#define FALSE 0
+#define NULL 0
+ 
+#endif

src/kernel/print.c

@@ -0,0 +1,110 @@
+#include "print.h"
+#include "./platform/drivers/ports.h"
+
+int row = 0;
+int col = 0;
+char color = PRINT_COLOR_WHITE | PRINT_COLOR_BLACK << 4;
+
+void clear_row(int row) {
+    struct Char* buffer = (struct Char*) 0xb8000;
+
+    struct Char empty = (struct Char) {
+        character: ' ',
+        color: color,
+    };
+
+    for (int x = 0; x < NUM_COLS; x++) {
+        buffer[x + NUM_COLS * row] = empty;
+    }
+    set_cursor_pos(col, row);
+}
+
+void clear_all() {
+    for (int i = 0; i < NUM_ROWS; i++) {
+        clear_row(i);
+    }
+    set_cursor_pos(col, row);
+}
+
+void print_newline() {
+    struct Char* buffer = (struct Char*) 0xb8000;
+
+    col = 0;
+
+    if (row < NUM_ROWS - 1) {
+        row++;
+        return;
+    }
+
+    for (int row = 1; row < NUM_ROWS; row++) {
+        for (int col = 0; col < NUM_COLS; col++) {
+            struct Char character = buffer[col + NUM_COLS * row];
+            buffer[col + NUM_COLS * (row - 1)] = character;
+        }
+    }
+
+    clear_row(NUM_COLS - 1);
+    set_cursor_pos(col, row);
+}
+
+void print_char(char character) {
+    struct Char* buffer = (struct Char*) 0xb8000;
+
+    if (character == '\n') {
+        print_newline();
+        return;
+    }
+
+    if (col > NUM_COLS) {
+        print_newline();
+    }
+
+    struct Char cr = (struct Char) {
+        character: character,
+        color: color,
+    };
+    buffer[col + NUM_COLS * row] = cr;
+
+    col++;
+    set_cursor_pos(col, row);
+}
+
+void print_str(char* str) {
+    for (int i = 0; 1; i++) {
+        char character = (char) str[i];
+
+        if (character == '\0') {
+            return;
+        }
+
+        print_char(character);
+    }
+}
+
+void print_set_color(char foreground, char background) {
+    color = foreground + (background << 4);
+}
+
+void set_cursor_pos(int col, int row) {
+   int offset = col + NUM_COLS * row;
+   port_byte_out(REG_SCREEN_CTRL, 14);
+   port_byte_out(REG_SCREEN_DATA, (unsigned char)(offset >> 8));
+   port_byte_out(REG_SCREEN_CTRL, 15);
+   port_byte_out(REG_SCREEN_DATA, (unsigned char)(offset & 0xff)); 
+}
+
+void kernel_msg_ok(char* msg) {
+	char ok_p1[] = "[ ";
+	char ok_p2[] = "OK ";
+	char ok_p3[] = "] ";
+	
+	print_set_color(PRINT_COLOR_WHITE, PRINT_COLOR_BLACK);
+	print_str(ok_p1);
+	
+	print_set_color(PRINT_COLOR_GREEN, PRINT_COLOR_BLACK);
+	print_str(ok_p2);
+	
+	print_set_color(PRINT_COLOR_WHITE, PRINT_COLOR_BLACK);
+	print_str(ok_p3);
+	print_str(msg);
+}

src/kernel/print.h

@@ -0,0 +1,44 @@
+#ifndef PRINT_H
+#define PRINT_H
+#define REG_SCREEN_CTRL 0x3d4
+#define REG_SCREEN_DATA 0x3d5
+
+enum {
+    PRINT_COLOR_BLACK = 0,
+	PRINT_COLOR_BLUE = 1,
+	PRINT_COLOR_GREEN = 2,
+	PRINT_COLOR_CYAN = 3,
+	PRINT_COLOR_RED = 4,
+	PRINT_COLOR_MAGENTA = 5,
+	PRINT_COLOR_BROWN = 6,
+	PRINT_COLOR_LIGHT_GRAY = 7,
+	PRINT_COLOR_DARK_GRAY = 8,
+	PRINT_COLOR_LIGHT_BLUE = 9,
+	PRINT_COLOR_LIGHT_GREEN = 10,
+	PRINT_COLOR_LIGHT_CYAN = 11,
+	PRINT_COLOR_LIGHT_RED = 12,
+	PRINT_COLOR_PINK = 13,
+	PRINT_COLOR_YELLOW = 14,
+	PRINT_COLOR_WHITE = 15,
+};
+
+const static int NUM_COLS = 80;
+const static int NUM_ROWS = 25;
+
+struct Char {
+    char character;
+    char color;
+};
+
+void clear_row(int row);
+void clear_all();
+
+void print_newline();
+void print_char(char character);
+void print_set_color(char foreground, char background);
+void print_str(char* str);
+
+void set_cursor_pos(int col, int row);
+
+void kernel_msg_ok(char* msg);
+#endif

src/kernel/strings.c

@@ -0,0 +1,48 @@
+#include "strings.h"
+#include "./platform/types.h"
+
+void itoa(int n, char str[]) {
+    int i, sign;
+    if ((sign = n) < 0) n = -n;
+    i = 0;
+    do {
+        str[i++] = n % 10 + '0';
+    } while ((n /= 10) > 0);
+
+    if (sign < 0) str[i++] = '-';
+    str[i] = '\0';
+
+    strrev(str);
+}
+
+/* K&R */
+void strrev(char s[]) {
+    int c, i, j;
+    for (i = 0, j = strlen(s)-1; i < j; i++, j--) {
+        c = s[i];
+        s[i] = s[j];
+        s[j] = c;
+    }
+}
+
+/* K&R */
+int strlen(char s[]) {
+    int i = 0;
+    while (s[i] != '\0') ++i;
+    return i;
+}
+
+char* strcpy(char* strDest, const char* strSrc) {
+    if ( (strDest == NULL) || (strSrc == NULL) ) {
+        return NULL;
+    }
+    char* strDestCopy = strDest;
+    while ((*strDest++=*strSrc++)!='\0');
+    return strDestCopy;
+}
+
+char* strcnc(char* str1, char* str2) {
+    char* str_dest;
+    strcpy(str_dest, str1);
+    strcpy(str_dest, str2);
+}

src/kernel/strings.h

@@ -0,0 +1,10 @@
+#ifndef STRINGS_H
+#define STRINGS_H
+
+void itoa(int n, char str[]);
+void strrev(char s[]);
+int strlen(char s[]);
+char* strcpy(char* strDest, const char* strSrc);
+char* strcnc(char* str1, char* str2);
+
+#endif

src/kernel/util.c

@@ -0,0 +1,25 @@
+#include "util.h"
+
+void memcpy(char *source, char *dest, int nbytes) {
+    int i;
+    for (i = 0; i < nbytes; i++) {
+        *(dest + i) = *(source + i);
+    }
+}
+
+void memset(char *dest, char val, int len) {
+    char *temp = (char *)dest;
+    for(; len !=0; len--) *temp++ = val;
+}
+
+void int_to_ascii(int n, char str[]) {
+    int i, sign;
+    if ((sign = n) < 0) n = -n;
+    i = 0;
+    do {
+        str[i++] = n % 10 + '0';
+    } while ((n /= 10) > 0);
+
+    if (sign < 0) str[i++] = '-';
+    str[i] = '\0';
+}

src/kernel/util.h

@@ -0,0 +1,8 @@
+#ifndef UTIL_H
+#define UTIL_H
+
+void memcpy(char *source, char *dest, int nbytes);
+void memset(char *dest, char val, int len);
+void int_to_ascii(int n, char str[]);
+
+#endif

src/linker.ld

@@ -0,0 +1,32 @@
+ENTRY(_start)
+
+SECTIONS
+{
+    . = 1M;
+
+    /* MB header */
+    .text BLOCK(4K) : ALIGN(4K)
+	{
+		*(.multiboot)
+		*(.text)
+	}
+
+    /* Read-only data. */
+	.rodata BLOCK(4K) : ALIGN(4K)
+	{
+		*(.rodata)
+	}
+ 
+	/* Read-write data (initialized) */
+	.data BLOCK(4K) : ALIGN(4K)
+	{
+		*(.data)
+	}
+ 
+	/* Read-write data (uninitialized) and stack */
+	.bss BLOCK(4K) : ALIGN(4K)
+	{
+		*(COMMON)
+		*(.bss)
+	}
+}