newlines and scrolling

8 files changed, 141 insertions, 121 deletions

diff --git a/Makefile b/Makefile
index f3f5b47..56ffd05 100644
--- a/Makefile
+++ b/Makefile
@@ -1,3 +1,4 @@
+SOURCE_DIR=src
 BUILD_DIR=build
 ISO_DIR=isodir
 
@@ -6,20 +7,20 @@ all: $(BUILD_DIR)/myos.bin
 	grub-file --is-x86-multiboot $(BUILD_DIR)/myos.bin
 	mkdir -p $(ISO_DIR)/boot/grub
 	cp $(BUILD_DIR)/myos.bin $(ISO_DIR)/boot/myos.bin
-	cp grub.cfg $(ISO_DIR)/boot/grub/grub.cfg
+	cp $(SOURCE_DIR)/grub.cfg $(ISO_DIR)/boot/grub/grub.cfg
 	grub-mkrescue -o myos.iso $(ISO_DIR)
 
-$(BUILD_DIR)/boot.o: boot.s
+$(BUILD_DIR)/boot.o: $(SOURCE_DIR)/boot.s
 	mkdir -p $(BUILD_DIR)
-	i686-elf-as boot.s -o $(BUILD_DIR)/boot.o
+	i686-elf-as $(SOURCE_DIR)/boot.s -o $(BUILD_DIR)/boot.o
 
-$(BUILD_DIR)/kernel.o: kernel.c
+$(BUILD_DIR)/kernel.o: $(SOURCE_DIR)/kernel.c
 	mkdir -p $(BUILD_DIR)
-	i686-elf-gcc -c kernel.c -o $(BUILD_DIR)/kernel.o -std=gnu99 -ffreestanding -O2 -Wall -Wextra
+	i686-elf-gcc -c $(SOURCE_DIR)/kernel.c -o $(BUILD_DIR)/kernel.o -std=gnu99 -ffreestanding -O2 -Wall -Wextra
 
 $(BUILD_DIR)/myos.bin: $(BUILD_DIR)/kernel.o $(BUILD_DIR)/boot.o
 	mkdir -p $(BUILD_DIR)
-	i686-elf-gcc -T linker.ld -o $(BUILD_DIR)/myos.bin -ffreestanding -O2 -nostdlib $(BUILD_DIR)/boot.o $(BUILD_DIR)/kernel.o -lgcc
+	i686-elf-gcc -T $(SOURCE_DIR)/linker.ld -o $(BUILD_DIR)/myos.bin -ffreestanding -O2 -nostdlib $(BUILD_DIR)/boot.o $(BUILD_DIR)/kernel.o -lgcc
 
 .PHONY: clean
 clean:
diff --git a/README.md b/README.md
index d4fecca..917cdb3 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,10 @@
-# mykernel
\ No newline at end of file
+# mykernel
+
+## i686-elf cross compiler
+First install binutils and gcc from your package manager. 
+On Arch based distributions they are available in AUR: 
+- [binutils](https://aur.archlinux.org/packages/i686-elf-binutils/) 
+- [gcc](https://aur.archlinux.org/packages/i686-elf-gcc/) 
+
+## Bare bones kernel in as and C
+[osdev](https://wiki.osdev.org/Bare_Bones)
diff --git a/kernel.c b/kernel.c
deleted file mode 100644
index 0516f16..0000000
--- a/kernel.c
+++ /dev/null
@@ -1,114 +0,0 @@
-#include <stdbool.h>
-#include <stddef.h>
-#include <stdint.h>
- 
-/* Check if the compiler thinks you are targeting the wrong operating system. */
-#if defined(__linux__)
-#error "You are not using a cross-compiler, you will most certainly run into trouble"
-#endif
- 
-/* This tutorial will only work for the 32-bit ix86 targets. */
-#if !defined(__i386__)
-#error "This tutorial needs to be compiled with a ix86-elf compiler"
-#endif
- 
-/* Hardware text mode color constants. */
-enum vga_color {
-	VGA_COLOR_BLACK = 0,
-	VGA_COLOR_BLUE = 1,
-	VGA_COLOR_GREEN = 2,
-	VGA_COLOR_CYAN = 3,
-	VGA_COLOR_RED = 4,
-	VGA_COLOR_MAGENTA = 5,
-	VGA_COLOR_BROWN = 6,
-	VGA_COLOR_LIGHT_GREY = 7,
-	VGA_COLOR_DARK_GREY = 8,
-	VGA_COLOR_LIGHT_BLUE = 9,
-	VGA_COLOR_LIGHT_GREEN = 10,
-	VGA_COLOR_LIGHT_CYAN = 11,
-	VGA_COLOR_LIGHT_RED = 12,
-	VGA_COLOR_LIGHT_MAGENTA = 13,
-	VGA_COLOR_LIGHT_BROWN = 14,
-	VGA_COLOR_WHITE = 15,
-};
- 
-static inline uint8_t vga_entry_color(enum vga_color fg, enum vga_color bg) 
-{
-	return fg | bg << 4;
-}
- 
-static inline uint16_t vga_entry(unsigned char uc, uint8_t color) 
-{
-	return (uint16_t) uc | (uint16_t) color << 8;
-}
- 
-size_t strlen(const char* str) 
-{
-	size_t len = 0;
-	while (str[len])
-		len++;
-	return len;
-}
- 
-static const size_t VGA_WIDTH = 80;
-static const size_t VGA_HEIGHT = 25;
- 
-size_t terminal_row;
-size_t terminal_column;
-uint8_t terminal_color;
-uint16_t* terminal_buffer;
- 
-void terminal_initialize(void) 
-{
-	terminal_row = 0;
-	terminal_column = 0;
-	terminal_color = vga_entry_color(VGA_COLOR_LIGHT_GREY, VGA_COLOR_BLACK);
-	terminal_buffer = (uint16_t*) 0xB8000;
-	for (size_t y = 0; y < VGA_HEIGHT; y++) {
-		for (size_t x = 0; x < VGA_WIDTH; x++) {
-			const size_t index = y * VGA_WIDTH + x;
-			terminal_buffer[index] = vga_entry(' ', terminal_color);
-		}
-	}
-}
- 
-void terminal_setcoor(uint8_t color) 
-{
-	terminal_color = color;
-}
- 
-void terminal_putentryat(char c, uint8_t color, size_t x, size_t y) 
-{
-	const size_t index = y * VGA_WIDTH + x;
-	terminal_buffer[index] = vga_entry(c, color);
-}
- 
-void terminal_putchar(char c) 
-{
-	terminal_putentryat(c, terminal_color, terminal_column, terminal_row);
-	if (++terminal_column == VGA_WIDTH) {
-		terminal_column = 0;
-		if (++terminal_row == VGA_HEIGHT)
-			terminal_row = 0;
-	}
-}
- 
-void terminal_write(const char* data, size_t size) 
-{
-	for (size_t i = 0; i < size; i++)
-		terminal_putchar(data[i]);
-}
- 
-void terminal_writestring(const char* data) 
-{
-	terminal_write(data, strlen(data));
-}
- 
-void kernel_main(void) 
-{
-	/* Initialize terminal interface */
-	terminal_initialize();
- 
-	/* Newline support is left as an exercise. */
-	terminal_writestring("Hello, kernel World!\n");
-}
diff --git a/boot.asm b/src/boot.asm
index 94b4c57..94b4c57 100644
--- a/boot.asm
+++ b/src/boot.asm
diff --git a/boot.s b/src/boot.s
index 172fd14..172fd14 100644
--- a/boot.s
+++ b/src/boot.s
diff --git a/grub.cfg b/src/grub.cfg
index b2f8404..b2f8404 100644
--- a/grub.cfg
+++ b/src/grub.cfg
diff --git a/src/kernel.c b/src/kernel.c
new file mode 100644
index 0000000..dd81d33
--- /dev/null
+++ b/src/kernel.c
@@ -0,0 +1,124 @@
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+ 
+/* Check if the compiler thinks you are targeting the wrong operating system. */
+#if defined(__linux__)
+#error "You are not using a cross-compiler, you will most certainly run into trouble"
+#endif
+ 
+/* This tutorial will only work for the 32-bit ix86 targets. */
+#if !defined(__i386__)
+#error "This tutorial needs to be compiled with a ix86-elf compiler"
+#endif
+ 
+/* Hardware text mode color constants. */
+enum vga_color {
+    VGA_COLOR_BLACK = 0,
+    VGA_COLOR_BLUE = 1,
+    VGA_COLOR_GREEN = 2,
+    VGA_COLOR_CYAN = 3,
+    VGA_COLOR_RED = 4,
+    VGA_COLOR_MAGENTA = 5,
+    VGA_COLOR_BROWN = 6,
+    VGA_COLOR_LIGHT_GREY = 7,
+    VGA_COLOR_DARK_GREY = 8,
+    VGA_COLOR_LIGHT_BLUE = 9,
+    VGA_COLOR_LIGHT_GREEN = 10,
+    VGA_COLOR_LIGHT_CYAN = 11,
+    VGA_COLOR_LIGHT_RED = 12,
+    VGA_COLOR_LIGHT_MAGENTA = 13,
+    VGA_COLOR_LIGHT_BROWN = 14,
+    VGA_COLOR_WHITE = 15,
+};
+ 
+static inline uint8_t vga_entry_color(enum vga_color fg, enum vga_color bg) 
+{
+    return fg | bg << 4;
+}
+ 
+static inline uint16_t vga_entry(unsigned char uc, uint8_t color) 
+{
+    return (uint16_t) uc | (uint16_t) color << 8;
+}
+ 
+size_t strlen(const char* str) 
+{
+    size_t len = 0;
+    while (str[len]) len++;
+    return len;
+}
+ 
+static const size_t VGA_WIDTH = 80;
+static const size_t VGA_HEIGHT = 25;
+ 
+size_t terminal_row;
+size_t terminal_column;
+uint8_t terminal_color;
+uint16_t* terminal_buffer;
+ 
+void terminal_initialize(void) 
+{
+    terminal_row = 0;
+    terminal_column = 0;
+    terminal_color = vga_entry_color(VGA_COLOR_LIGHT_GREY, VGA_COLOR_BLACK);
+    terminal_buffer = (uint16_t*) 0xB8000;
+    for (size_t y = 0; y < VGA_HEIGHT; y++) {
+	for (size_t x = 0; x < VGA_WIDTH; x++) {
+	    const size_t index = y * VGA_WIDTH + x;
+	    terminal_buffer[index] = vga_entry(' ', terminal_color);
+	}
+    }
+}
+ 
+void terminal_setcoor(uint8_t color) 
+{
+    terminal_color = color;
+}
+ 
+void terminal_putentryat(char c, uint8_t color, size_t x, size_t y) 
+{
+    const size_t index = y * VGA_WIDTH + x;
+    terminal_buffer[index] = vga_entry(c, color);
+}
+
+void movescreen()
+{
+    if (terminal_row == VGA_HEIGHT)
+    {
+	terminal_row--;
+	for(size_t i=0;i<VGA_HEIGHT;i++) for(size_t j=0;j<VGA_WIDTH;j++) terminal_buffer[i*VGA_WIDTH+j]=terminal_buffer[(i+1)*VGA_WIDTH+j];
+    }
+}
+ 
+void terminal_putchar(char c) 
+{
+    if(c=='\n') terminal_column = 0,terminal_row++;
+    else
+    {
+	terminal_putentryat(c, terminal_color, terminal_column, terminal_row);
+	if (++terminal_column == VGA_WIDTH) terminal_column = 0,terminal_row++;
+    }
+    if (terminal_row == VGA_HEIGHT) movescreen();
+}
+ 
+void terminal_write(const char* data, size_t size) 
+{
+    for (size_t i = 0; i < size; i++) terminal_putchar(data[i]);
+}
+ 
+void terminal_writestring(const char* data) 
+{
+    terminal_write(data, strlen(data));
+}
+ 
+void kernel_main(void) 
+{
+    terminal_initialize();
+
+    for(size_t i=0;i<80;i++)
+    {
+	for(size_t j=0;j<i;j++) terminal_writestring("#");
+	terminal_writestring("Hello, kernel World!\n");
+    }
+}
diff --git a/linker.ld b/src/linker.ld
index 38ddd94..38ddd94 100644
--- a/linker.ld
+++ b/src/linker.ld