Initial commit

.gitignore

@@ -0,0 +1,4 @@
+*.iso
+isodir
+tools
+sysroot

TODO.org

@@ -0,0 +1,7 @@
+#+TITLE: TODO for BareBones article-based OS on C
+
+* DONE Newline support
+* TODO Implement terminal scrolling
+* TODO Colors changing (for ASCII arts)
+* TODO Calling Global Constructors
+  

build.sh

@@ -0,0 +1,7 @@
+#!/bin/sh
+set -e
+. ./headers.sh
+
+for PROJECT in $PROJECTS; do
+	(cd $PROJECT && DESTDIR="$SYSROOT" $MAKE -j$(nproc) install)
+done

clean.sh

@@ -0,0 +1,11 @@
+#!/bin/sh
+set -e
+. ./config.sh
+
+for PROJECT in $PROJECTS; do
+  (cd $PROJECT && $MAKE clean)
+done
+
+rm -rf sysroot
+rm -rf isodir
+rm -rf orion.iso

config.sh

@@ -0,0 +1,28 @@
+SYSTEM_HEADER_PROJECTS="libc kernel"
+PROJECTS="libc kernel"
+
+export MAKE=${MAKE:-make}
+export HOST=${HOST:-$(./default-host.sh)}
+
+export AR=${HOST}-ar
+export AS=${HOST}-as
+export CC=${HOST}-gcc
+
+export PREFIX=/usr
+export EXEC_PREFIX=$PREFIX
+export BOOTDIR=/boot
+export LIBDIR=$EXEC_PREFIX/lib
+export INCLUDEDIR=$PREFIX/include
+
+export CFLAGS='-O2 -g'
+export CPPFLAGS=''
+
+# Configure the cross-compiler to use the desired system root.
+export SYSROOT="$(pwd)/sysroot"
+export CC="$CC --sysroot=$SYSROOT"
+
+# Work around that the -elf gcc targets doesn't have a system include directory
+# because it was configured with --without-headers rather than --with-sysroot.
+if echo "$HOST" | grep -Eq -- '-elf($|-)'; then
+  export CC="$CC -isystem=$INCLUDEDIR"
+fi

default-host.sh

@@ -0,0 +1,2 @@
+#!/bin/sh
+echo i686-elf

headers.sh

@@ -0,0 +1,9 @@
+#!/bin/sh
+set -e
+. ./config.sh
+
+mkdir -p "$SYSROOT"
+
+for PROJECT in $SYSTEM_HEADER_PROJECTS; do
+  (cd $PROJECT && DESTDIR="$SYSROOT" $MAKE install-headers)
+done

iso.sh

@@ -0,0 +1,15 @@
+#!/bin/sh
+set -e
+. ./build.sh
+
+mkdir -p isodir
+mkdir -p isodir/boot
+mkdir -p isodir/boot/grub
+
+cp sysroot/boot/orion.kernel isodir/boot/orion.kernel
+cat > isodir/boot/grub/grub.cfg << EOF
+menuentry "orion" {
+	multiboot /boot/orion.kernel
+}
+EOF
+grub-mkrescue -o orion.iso isodir

kernel/.gitignore

@@ -0,0 +1,3 @@
+*.d
+*.kernel
+*.o

kernel/Makefile

@@ -0,0 +1,83 @@
+DEFAULT_HOST!=../default-host.sh
+HOST?=DEFAULT_HOST
+HOSTARCH!=../target-triplet-to-arch.sh $(HOST)
+
+CFLAGS?=-O2 -g
+CPPFLAGS?=
+LDFLAGS?=
+LIBS?=
+
+DESTDIR?=
+PREFIX?=/usr/local
+EXEC_PREFIX?=$(PREFIX)
+BOOTDIR?=$(EXEC_PREFIX)/boot
+INCLUDEDIR?=$(PREFIX)/include
+
+CFLAGS:=$(CFLAGS) -ffreestanding -Wall -Wextra
+CPPFLAGS:=$(CPPFLAGS) -D__is_kernel -Iinclude
+LDFLAGS:=$(LDFLAGS)
+LIBS:=$(LIBS) -nostdlib -lk -lgcc
+
+ARCHDIR=arch/$(HOSTARCH)
+
+include $(ARCHDIR)/make.config
+
+CFLAGS:=$(CFLAGS) $(KERNEL_ARCH_CFLAGS)
+CPPFLAGS:=$(CPPFLAGS) $(KERNEL_ARCH_CPPFLAGS)
+LDFLAGS:=$(LDFLAGS) $(KERNEL_ARCH_LDFLAGS)
+LIBS:=$(LIBS) $(KERNEL_ARCH_LIBS)
+
+KERNEL_OBJS=\
+$(KERNEL_ARCH_OBJS) \
+kernel/kernel.o \
+
+OBJS=\
+$(ARCHDIR)/crti.o \
+$(ARCHDIR)/crtbegin.o \
+$(KERNEL_OBJS) \
+$(ARCHDIR)/crtend.o \
+$(ARCHDIR)/crtn.o \
+
+LINK_LIST=\
+$(LDFLAGS) \
+$(ARCHDIR)/crti.o \
+$(ARCHDIR)/crtbegin.o \
+$(KERNEL_OBJS) \
+$(LIBS) \
+$(ARCHDIR)/crtend.o \
+$(ARCHDIR)/crtn.o \
+
+.PHONY: all clean install install-headers install-kernel
+.SUFFIXES: .o .c .S
+
+all: orion.kernel
+
+orion.kernel: $(OBJS) $(ARCHDIR)/linker.ld
+	$(CC) -T $(ARCHDIR)/linker.ld -o $@ $(CFLAGS) $(LINK_LIST)
+	grub-file --is-x86-multiboot orion.kernel
+
+$(ARCHDIR)/crtbegin.o $(ARCHDIR)/crtend.o:
+	OBJ=`$(CC) $(CFLAGS) $(LDFLAGS) -print-file-name=$(@F)` && cp "$$OBJ" $@
+
+.c.o:
+	$(CC) -MD -c $< -o $@ -std=gnu11 $(CFLAGS) $(CPPFLAGS)
+
+.S.o:
+	$(CC) -MD -c $< -o $@ $(CFLAGS) $(CPPFLAGS)
+
+clean:
+	rm -f orion.kernel
+	rm -f $(OBJS) *.o */*.o */*/*.o
+	rm -f $(OBJS:.o=.d) *.d */*.d */*/*.d
+
+install: install-headers install-kernel
+
+install-headers:
+	mkdir -p $(DESTDIR)$(INCLUDEDIR)
+	cp -R --preserve=timestamps include/. $(DESTDIR)$(INCLUDEDIR)/.
+
+install-kernel: orion.kernel
+	mkdir -p $(DESTDIR)$(BOOTDIR)
+	cp orion.kernel $(DESTDIR)$(BOOTDIR)
+
+-include $(OBJS:.o=.d)

kernel/arch/i386/boot.S

@@ -0,0 +1,39 @@
+# Declare constants for the multiboot header.
+.set ALIGN,    1<<0             # align loaded modules on page boundaries
+.set MEMINFO,  1<<1             # provide memory map
+.set FLAGS,    ALIGN | MEMINFO  # this is the Multiboot 'flag' field
+.set MAGIC,    0x1BADB002       # 'magic number' lets bootloader find the header
+.set CHECKSUM, -(MAGIC + FLAGS) # checksum of above, to prove we are multiboot
+
+# Declare a header as in the Multiboot Standard.
+.section .multiboot
+.align 4
+.long MAGIC
+.long FLAGS
+.long CHECKSUM
+
+# Reserve a stack for the initial thread.
+.section .bss
+.align 16
+stack_bottom:
+.skip 16384 # 16 KiB
+stack_top:
+
+# The kernel entry point.
+.section .text
+.global _start
+.type _start, @function
+_start:
+	movl $stack_top, %esp
+
+	# Call the global constructors.
+	call _init
+
+	# Transfer control to the main kernel.
+	call kernel_main
+
+	# Hang if kernel_main unexpectedly returns.
+	cli
+1:	hlt
+	jmp 1b
+.size _start, . - _start

kernel/arch/i386/crti.S

@@ -0,0 +1,15 @@
+.section .init
+.global _init
+.type _init, @function
+_init:
+	push %ebp
+	movl %esp, %ebp
+	/* gcc will nicely put the contents of crtbegin.o's .init section here. */
+
+.section .fini
+.global _fini
+.type _fini, @function
+_fini:
+	push %ebp
+	movl %esp, %ebp
+	/* gcc will nicely put the contents of crtbegin.o's .fini section here. */

kernel/arch/i386/crtn.S

@@ -0,0 +1,9 @@
+.section .init
+	/* gcc will nicely put the contents of crtend.o's .init section here. */
+	popl %ebp
+	ret
+
+.section .fini
+	/* gcc will nicely put the contents of crtend.o's .fini section here. */
+	popl %ebp
+	ret

kernel/arch/i386/linker.ld

@@ -0,0 +1,43 @@
+/* The bootloader will look at this image and start execution at the symbol
+   designated at the entry point. */
+ENTRY(_start)
+
+/* Tell where the various sections of the object files will be put in the final
+   kernel image. */
+SECTIONS
+{
+	/* Begin putting sections at 1 MiB, a conventional place for kernels to be
+	   loaded at by the bootloader. */
+	. = 1M;
+
+	/* First put the multiboot header, as it is required to be put very early
+	   early in the image or the bootloader won't recognize the file format.
+	   Next we'll put the .text section. */
+	.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)
+	}
+
+	/* The compiler may produce other sections, put them in the proper place in
+	   in this file, if you'd like to include them in the final kernel. */
+}

kernel/arch/i386/make.config

@@ -0,0 +1,8 @@
+KERNEL_ARCH_CFLAGS=
+KERNEL_ARCH_CPPFLAGS=
+KERNEL_ARCH_LDFLAGS=
+KERNEL_ARCH_LIBS=
+
+KERNEL_ARCH_OBJS=\
+$(ARCHDIR)/boot.o \
+$(ARCHDIR)/tty.o \

kernel/arch/i386/tty.c

@@ -0,0 +1,89 @@
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <string.h>
+
+#include <kernel/tty.h>
+
+#include "vga.h"
+
+static const size_t VGA_WIDTH = 80;
+static const size_t VGA_HEIGHT = 25;
+static uint16_t* const VGA_MEMORY = (uint16_t*) 0xB8000;
+
+static size_t terminal_row;
+static size_t terminal_column;
+static uint8_t terminal_color;
+static 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 = VGA_MEMORY;
+	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_setcolor(uint8_t color) {
+	terminal_color = color;
+}
+
+void terminal_putentryat(unsigned 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_scroll(int line) {
+	int loop;
+	int c;
+ 
+	for(loop = line * (VGA_WIDTH * 2) + 0xB8000; loop < VGA_WIDTH * 2; loop++) {
+		c = loop;
+		//*(loop - (VGA_WIDTH * 2)) = c;
+	}
+}
+
+ 
+void terminal_delete_last_line() {
+	int x, *ptr;
+ 
+	for(x = 0; x < VGA_WIDTH * 2; x++) {
+		ptr = 0xB8000 + (VGA_WIDTH * 2) * (VGA_HEIGHT - 1) + x;
+		*ptr = 0;
+	}
+}
+
+void terminal_putchar(char c) {
+	unsigned char uc = c;
+	terminal_putentryat(uc, terminal_color, terminal_column, terminal_row);
+	if (c != '\n') {
+	  if (++terminal_column == VGA_WIDTH) {
+	    terminal_column = 0;
+	    if (++terminal_row == VGA_HEIGHT) {
+	      for(int line = 1; line <= VGA_HEIGHT - 1; line++)
+			{
+				terminal_scroll(line);
+			}
+			terminal_delete_last_line();
+			terminal_row = VGA_HEIGHT - 1;
+	    }
+	  }
+	} else {
+	  terminal_row += 1;
+	  terminal_column = 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));
+}

kernel/arch/i386/vga.h

@@ -0,0 +1,33 @@
+#ifndef ARCH_I386_VGA_H
+#define ARCH_I386_VGA_H
+
+#include <stdint.h>
+
+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;
+}
+
+#endif

kernel/include/kernel/tty.h

@@ -0,0 +1,11 @@
+#ifndef _KERNEL_TTY_H
+#define _KERNEL_TTY_H
+
+#include <stddef.h>
+
+void terminal_initialize(void);
+void terminal_putchar(char c);
+void terminal_write(const char* data, size_t size);
+void terminal_writestring(const char* data);
+
+#endif

kernel/kernel/kernel.c

@@ -0,0 +1,8 @@
+#include <stdio.h>
+
+#include <kernel/tty.h>
+
+void kernel_main(void) {
+	terminal_initialize();
+	printf("Hello from OrionOS!\n");
+}

libc/.gitignore

@@ -0,0 +1,3 @@
+*.a
+*.d
+*.o

libc/Makefile

@@ -0,0 +1,93 @@
+DEFAULT_HOST!=../default-host.sh
+HOST?=DEFAULT_HOST
+HOSTARCH!=../target-triplet-to-arch.sh $(HOST)
+
+CFLAGS?=-O2 -g
+CPPFLAGS?=
+LDFLAGS?=
+LIBS?=
+
+DESTDIR?=
+PREFIX?=/usr/local
+EXEC_PREFIX?=$(PREFIX)
+INCLUDEDIR?=$(PREFIX)/include
+LIBDIR?=$(EXEC_PREFIX)/lib
+
+CFLAGS:=$(CFLAGS) -ffreestanding -Wall -Wextra
+CPPFLAGS:=$(CPPFLAGS) -D__is_libc -Iinclude
+LIBK_CFLAGS:=$(CFLAGS)
+LIBK_CPPFLAGS:=$(CPPFLAGS) -D__is_libk
+
+ARCHDIR=arch/$(HOSTARCH)
+
+include $(ARCHDIR)/make.config
+
+CFLAGS:=$(CFLAGS) $(ARCH_CFLAGS)
+CPPFLAGS:=$(CPPFLAGS) $(ARCH_CPPFLAGS)
+LIBK_CFLAGS:=$(LIBK_CFLAGS) $(KERNEL_ARCH_CFLAGS)
+LIBK_CPPFLAGS:=$(LIBK_CPPFLAGS) $(KERNEL_ARCH_CPPFLAGS)
+
+FREEOBJS=\
+$(ARCH_FREEOBJS) \
+stdio/printf.o \
+stdio/putchar.o \
+stdio/puts.o \
+stdlib/abort.o \
+string/memcmp.o \
+string/memcpy.o \
+string/memmove.o \
+string/memset.o \
+string/strlen.o \
+
+HOSTEDOBJS=\
+$(ARCH_HOSTEDOBJS) \
+
+OBJS=\
+$(FREEOBJS) \
+$(HOSTEDOBJS) \
+
+LIBK_OBJS=$(FREEOBJS:.o=.libk.o)
+
+#BINARIES=libc.a libk.a # Not ready for libc yet.
+BINARIES=libk.a
+
+.PHONY: all clean install install-headers install-libs
+.SUFFIXES: .o .libk.o .c .S
+
+all: $(BINARIES)
+
+libc.a: $(OBJS)
+	$(AR) rcs $@ $(OBJS)
+
+libk.a: $(LIBK_OBJS)
+	$(AR) rcs $@ $(LIBK_OBJS)
+
+.c.o:
+	$(CC) -MD -c $< -o $@ -std=gnu11 $(CFLAGS) $(CPPFLAGS)
+
+.c.S:
+	$(CC) -MD -c $< -o $@ $(CFLAGS) $(CPPFLAGS)
+
+.c.libk.o:
+	$(CC) -MD -c $< -o $@ -std=gnu11 $(LIBK_CFLAGS) $(LIBK_CPPFLAGS)
+
+.S.libk.o:
+	$(CC) -MD -c $< -o $@ $(LIBK_CFLAGS) $(LIBK_CPPFLAGS)
+
+clean:
+	rm -f $(BINARIES) *.a
+	rm -f $(OBJS) $(LIBK_OBJS) *.o */*.o */*/*.o
+	rm -f $(OBJS:.o=.d) $(LIBK_OBJS:.o=.d) *.d */*.d */*/*.d
+
+install: install-headers install-libs
+
+install-headers:
+	mkdir -p $(DESTDIR)$(INCLUDEDIR)
+	cp -R --preserve=timestamps include/. $(DESTDIR)$(INCLUDEDIR)/.
+
+install-libs: $(BINARIES)
+	mkdir -p $(DESTDIR)$(LIBDIR)
+	cp $(BINARIES) $(DESTDIR)$(LIBDIR)
+
+-include $(OBJS:.o=.d)
+-include $(LIBK_OBJS:.o=.d)

libc/arch/i386/make.config

@@ -0,0 +1,8 @@
+ARCH_CFLAGS=
+ARCH_CPPFLAGS=
+KERNEL_ARCH_CFLAGS=
+KERNEL_ARCH_CPPFLAGS=
+
+ARCH_FREEOBJS=\
+
+ARCH_HOSTEDOBJS=\

libc/include/stdio.h

@@ -0,0 +1,20 @@
+#ifndef _STDIO_H
+#define _STDIO_H 1
+
+#include <sys/cdefs.h>
+
+#define EOF (-1)
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+int printf(const char* __restrict, ...);
+int putchar(int);
+int puts(const char*);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

libc/include/stdlib.h

@@ -0,0 +1,17 @@
+#ifndef _STDLIB_H
+#define _STDLIB_H 1
+
+#include <sys/cdefs.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+__attribute__((__noreturn__))
+void abort(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

libc/include/string.h

@@ -0,0 +1,22 @@
+#ifndef _STRING_H
+#define _STRING_H 1
+
+#include <sys/cdefs.h>
+
+#include <stddef.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+int memcmp(const void*, const void*, size_t);
+void* memcpy(void* __restrict, const void* __restrict, size_t);
+void* memmove(void*, const void*, size_t);
+void* memset(void*, int, size_t);
+size_t strlen(const char*);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

libc/include/sys/cdefs.h

@@ -0,0 +1,6 @@
+#ifndef _SYS_CDEFS_H
+#define _SYS_CDEFS_H 1
+
+#define __orion_libc 1
+
+#endif

libc/stdio/printf.c

@@ -0,0 +1,80 @@
+#include <limits.h>
+#include <stdbool.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <string.h>
+
+static bool print(const char* data, size_t length) {
+	const unsigned char* bytes = (const unsigned char*) data;
+	for (size_t i = 0; i < length; i++)
+		if (putchar(bytes[i]) == EOF)
+			return false;
+	return true;
+}
+
+int printf(const char* restrict format, ...) {
+	va_list parameters;
+	va_start(parameters, format);
+
+	int written = 0;
+
+	while (*format != '\0') {
+		size_t maxrem = INT_MAX - written;
+
+		if (format[0] != '%' || format[1] == '%') {
+			if (format[0] == '%')
+				format++;
+			size_t amount = 1;
+			while (format[amount] && format[amount] != '%')
+				amount++;
+			if (maxrem < amount) {
+				// TODO: Set errno to EOVERFLOW.
+				return -1;
+			}
+			if (!print(format, amount))
+				return -1;
+			format += amount;
+			written += amount;
+			continue;
+		}
+
+		const char* format_begun_at = format++;
+
+		if (*format == 'c') {
+			format++;
+			char c = (char) va_arg(parameters, int /* char promotes to int */);
+			if (!maxrem) {
+				// TODO: Set errno to EOVERFLOW.
+				return -1;
+			}
+			if (!print(&c, sizeof(c)))
+				return -1;
+			written++;
+		} else if (*format == 's') {
+			format++;
+			const char* str = va_arg(parameters, const char*);
+			size_t len = strlen(str);
+			if (maxrem < len) {
+				// TODO: Set errno to EOVERFLOW.
+				return -1;
+			}
+			if (!print(str, len))
+				return -1;
+			written += len;
+		} else {
+			format = format_begun_at;
+			size_t len = strlen(format);
+			if (maxrem < len) {
+				// TODO: Set errno to EOVERFLOW.
+				return -1;
+			}
+			if (!print(format, len))
+				return -1;
+			written += len;
+			format += len;
+		}
+	}
+
+	va_end(parameters);
+	return written;
+}

libc/stdio/putchar.c

@@ -0,0 +1,15 @@
+#include <stdio.h>
+
+#if defined(__is_libk)
+#include <kernel/tty.h>
+#endif
+
+int putchar(int ic) {
+#if defined(__is_libk)
+	char c = (char) ic;
+	terminal_write(&c, sizeof(c));
+#else
+	// TODO: Implement stdio and the write system call.
+#endif
+	return ic;
+}

libc/stdio/puts.c

@@ -0,0 +1,5 @@
+#include <stdio.h>
+
+int puts(const char* string) {
+	return printf("%s\n", string);
+}

libc/stdlib/abort.c

@@ -0,0 +1,15 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+__attribute__((__noreturn__))
+void abort(void) {
+#if defined(__is_libk)
+	// TODO: Add proper kernel panic.
+	printf("kernel: panic: abort()\n");
+#else
+	// TODO: Abnormally terminate the process as if by SIGABRT.
+	printf("abort()\n");
+#endif
+	while (1) { }
+	__builtin_unreachable();
+}

libc/string/memcmp.c

@@ -0,0 +1,13 @@
+#include <string.h>
+
+int memcmp(const void* aptr, const void* bptr, size_t size) {
+	const unsigned char* a = (const unsigned char*) aptr;
+	const unsigned char* b = (const unsigned char*) bptr;
+	for (size_t i = 0; i < size; i++) {
+		if (a[i] < b[i])
+			return -1;
+		else if (b[i] < a[i])
+			return 1;
+	}
+	return 0;
+}

libc/string/memcpy.c

@@ -0,0 +1,9 @@
+#include <string.h>
+
+void* memcpy(void* restrict dstptr, const void* restrict srcptr, size_t size) {
+	unsigned char* dst = (unsigned char*) dstptr;
+	const unsigned char* src = (const unsigned char*) srcptr;
+	for (size_t i = 0; i < size; i++)
+		dst[i] = src[i];
+	return dstptr;
+}

libc/string/memmove.c

@@ -0,0 +1,14 @@
+#include <string.h>
+
+void* memmove(void* dstptr, const void* srcptr, size_t size) {
+	unsigned char* dst = (unsigned char*) dstptr;
+	const unsigned char* src = (const unsigned char*) srcptr;
+	if (dst < src) {
+		for (size_t i = 0; i < size; i++)
+			dst[i] = src[i];
+	} else {
+		for (size_t i = size; i != 0; i--)
+			dst[i-1] = src[i-1];
+	}
+	return dstptr;
+}

libc/string/memset.c

@@ -0,0 +1,8 @@
+#include <string.h>
+
+void* memset(void* bufptr, int value, size_t size) {
+	unsigned char* buf = (unsigned char*) bufptr;
+	for (size_t i = 0; i < size; i++)
+		buf[i] = (unsigned char) value;
+	return bufptr;
+}

libc/string/strlen.c

@@ -0,0 +1,8 @@
+#include <string.h>
+
+size_t strlen(const char* str) {
+	size_t len = 0;
+	while (str[len])
+		len++;
+	return len;
+}

qemu-only-kernel.sh

@@ -0,0 +1,5 @@
+#!/bin/sh
+set -e
+. ./build.sh
+
+qemu-system-x86_64 -kernel sysroot/boot/orion.kernel

qemu.sh

@@ -0,0 +1,5 @@
+#!/bin/sh
+set -e
+. ./iso.sh
+
+qemu-system-x86_64 -cdrom orion.iso

target-triplet-to-arch.sh

@@ -0,0 +1,6 @@
+#!/bin/sh
+if echo "$1" | grep -Eq 'i[[:digit:]]86-'; then
+  echo i386
+else
+  echo "$1" | grep -Eo '^[[:alnum:]_]*'
+fi