Initial commit

8 files changed, 99 insertions, 0 deletions

diff --git a/bin/dummy.bin b/bin/dummy.bin
new file mode 100644
index 0000000..6f2016c
--- /dev/null
+++ b/bin/dummy.bin
diff --git a/bootloader.asm b/bootloader.asm
new file mode 100644
index 0000000..181c1dc
--- /dev/null
+++ b/bootloader.asm
@@ -0,0 +1,12 @@
+
+  mov cx, 0x10
+  mov ah, 0x0A
+  mov al, 0x74
+  int 0x10
+
+hang:
+  jmp hang
+
+  times 510-($-$$) db 0
+  db 0x55
+  db 0xAA
diff --git a/build/bootloader.sh b/build/bootloader.sh
new file mode 100755
index 0000000..b56bb3d
--- /dev/null
+++ b/build/bootloader.sh
@@ -0,0 +1,3 @@
+#! /bin/sh
+FILENAME="bootloader"
+nasm "$FILENAME".asm -f bin -o "$FILENAME".bin
diff --git a/build/compile.sh b/build/compile.sh
new file mode 100755
index 0000000..efd8962
--- /dev/null
+++ b/build/compile.sh
@@ -0,0 +1,7 @@
+#! /bin/sh
+IN=$1
+FILE=$(basename $1)
+gcc -masm=intel -nostartfiles -nostdlib -ffreestanding "$IN".c -o "tmp/$FILE".o
+objcopy -S -R .note.gnu.build-id -R .comment -O binary "tmp/$FILE".o "bim/$FILE".bin
+rm "$IN".o
+
diff --git a/build/splicetobootsect.sh b/build/splicetobootsect.sh
new file mode 100755
index 0000000..6a2c353
--- /dev/null
+++ b/build/splicetobootsect.sh
@@ -0,0 +1,18 @@
+#! /bin/bash
+if [[ $1 == "" ]]; then
+  echo "Argument must be the path to a binary to splice into a bootsector"
+  exit 1
+fi
+
+INSIZE=$(stat -c%s $1)
+if [ $INSIZE -ge 510 ]; then
+  echo "Input file is greater than bootsector max size: 510 bytes."
+  exit 1
+fi
+
+OUTFILE="$(basename $1)_with_bootsect.bin"
+echo "Initializing output file"
+dd if=bin/dummy.bin of="$OUTFILE" >/dev/null 2>&1
+echo "Splicing binary"
+dd if="$1" of="$OUTFILE" conv=notrunc >/dev/null 2>&1
+echo "Done"
diff --git a/linker.ld b/linker.ld
new file mode 100644
index 0000000..1b34e93
--- /dev/null
+++ b/linker.ld
@@ -0,0 +1,44 @@
+/* The bootloader will look at this image and start execution at the symbol
+   designated as 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)
+    *(.bootstrap_stack)
+  }
+
+  /* The compiler may produce other sections, by default it will put them in
+     a segment with the same name. Simply add stuff here as needed. */
+}
diff --git a/runemu.sh b/runemu.sh
new file mode 100755
index 0000000..aaee739
--- /dev/null
+++ b/runemu.sh
@@ -0,0 +1,4 @@
+#! /bin/sh
+
+qemu-system-x86_64 "$1"
+
diff --git a/src/kernel/main.c b/src/kernel/main.c
new file mode 100644
index 0000000..90f82f4
--- /dev/null
+++ b/src/kernel/main.c
@@ -0,0 +1,11 @@
+int func() {
+  asm(
+    ".intel_syntax noprefix \n"
+    "mov eax, 42 \n"
+    "ret         \n"
+  );
+}
+
+int _start() {
+  return 1;
+}