Initial commit

build.sh

@@ -0,0 +1,7 @@
+#!/bin/sh
+set -e
+. ./headers.sh
+
+for PROJECT in $PROJECTS; do
+    (cd $PROJECT && DESTDIR="$SYSROOT" $MAKE 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 rockos.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=$PREFIX/include
+
+export CFLAGS='-O3 -g'
+export CPPFLAGS=''
+
+# Configure the cross-compiler to use the desired system root.
+export SYSROOT="$(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/rockos.kernel isodir/boot/rockos.kernel
+cat > isodir/boot/grub/grub.cfg << EOF
+menuentry "rockOS" {
+    multiboot /boot/rockos.kernel
+}
+EOF
+grub2-mkrescue -o rockos.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 $(HOST)
+
+CFLAGS?=-O3 -g
+CPPFLAGS?=
+LDFLAGS?=
+LIBS?=
+
+DESTDIR?=
+PREFIX?=/usr/local
+EXEC_PREFIX?=$(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) $(KERNEL_ARCH_FLAGS)
+CPPFLAGS:=$(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: rockos.kernel
+
+rockos.kernel: $(OBJS) $(ARCHDIR)/linker.ld
+	$(CC) -T $(ARCHDIR)/linker.ld -o $@ $(CFLAGS) $(LINK_LIST)
+	grub2-file --is-x86-multiboot rockos.kernel
+
+$(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 rockos.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: rockos.kernel
+	mkdir -p $(DESTDIR)$(BOOTDIR)
+	cp rockos.kernel $(DESTDIR)$(BOOTDIR)
+
+-include $(OBJS:.o=.d)

kernel/arch/i386/boot.S

@@ -0,0 +1,34 @@
+# Declare constants for multiboot header
+.set ALIGN,     1<<0                # align loaded modules on page boundaries
+.set MEMINFO,   1<<1                # provide memory map
+.set FLAGS,     ALIGN | MEMINFO     # multiboot flag field
+.set MAGIC,     0x1BADB002          # magic number for bootloader to find header
+.set CHECKSUM,  -(MAGIC + FLAGS)    # checksum of above
+
+# Declare header in multiboot standard
+.section .multiboot
+.align 4
+.long MAGIC
+.long FLAGS
+.long CHECKSUM
+
+# Reserve a stack for initial thread
+.section .bss
+.align 16
+stack_bottom:
+.skip 16384 # 16 KiB
+stack_top:
+
+# kernel entry point
+.section .text
+.global _start
+.type _start, @function
+_start:
+    movl $stack_top, %esp
+    call _init          # call global constructors
+    call kernel_main    # transfer control to main kernel
+    # Hang if kernel_main unexpectedly returns
+    cli
+1:  hlt
+    jmp 1b
+.size _start, . - _start

kernel/arch/i386/crti.S

@@ -0,0 +1,13 @@
+.section .init
+.global _init
+.type _init, @function
+_init:
+    push %ebp
+    movl %esp, %ebp
+
+.section .fini
+.global _fini
+.type _fini, @function
+_fini:
+    push %ebp
+    movl %esp, %ebp

kernel/arch/i386/crtn.S

@@ -0,0 +1,7 @@
+.section .init
+    popl %ebp
+    ret
+
+.section .fini
+    popl %ebp
+    ret

kernel/arch/i386/linker.ld

@@ -0,0 +1,28 @@
+ENTRY(_start)
+
+SECTIONS
+{
+    . = 1M;
+
+    .text BLOCK(4K) : ALIGN(4K)
+    {
+        *(.multiboot)
+        *(.text)
+    }
+
+    .rodata BLOCK(4K) : ALIGN(4K)
+    {
+        *(.rodata)
+    }
+
+    .data BLOCK(4K) : ALIGN(4K)
+    {
+        *(.data)
+    }
+
+    .bss BLOCK(4K) : ALIGN(4K)
+    {
+        *(COMMON)
+        *(.bss)
+    }
+}

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 +1,62 @@
+#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_putchar(char c) {
+    unsigned char uc = c;
+
+    terminal_putentryat(uc, 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));
+}

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, kernel World!\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 $(HOST)
+
+CFLAGS?=-O3 -g
+CPPFLAGS?=
+LDFLAGS?=
+LIBS?=
+
+DESTDIR?=
+PREFIX?=/usr/local
+EXEC_PREFIX?=$(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 +1,21 @@
+#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 __rockos_libc 1
+
+#endif

libc/stdio/printf.c

@@ -0,0 +1,88 @@
+#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);
+            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 +1,16 @@
+#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");
+        asm volatile("hlt");
+    #else
+        // TODO: Abnormally terminate the process as if by SIGABRT.
+        printf("abort()\n");
+    #endif
+        while (1) {}
+        __builtin_unreachable();
+}

libc/string/memcmp.c

@@ -0,0 +1,14 @@
+#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 +1,10 @@
+#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 +1,17 @@
+#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 +1,9 @@
+#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 +1,9 @@
+#include <string.h>
+
+size_t strlen(const char* str) {
+    size_t len = 0;
+    while (str[len]) {
+        len++;
+    }
+    return len;
+}

qemu.sh

@@ -0,0 +1,5 @@
+#!/bin/sh
+set -e
+. ./iso.sh
+
+qemu-system-$(./target-triplet-to-arch.sh $HOST) -cdrom rockos.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