CMakeLists.txt

@@ -0,0 +1,18 @@
+cmake_minimum_required(VERSION 3.16)
+project(ClaudeOS C ASM)
+
+set(CMAKE_C_STANDARD 99)
+
+# We are building a kernel, so we don't want standard libraries
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -ffreestanding -m32 -g -O2 -Wall -Wextra")
+set(CMAKE_ASM_FLAGS "${CMAKE_ASM_FLAGS} -m32")
+set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -m32 -nostdlib")
+
+# Define build output directory
+set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib)
+set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/lib)
+set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)
+
+add_subdirectory(src)
+# add_subdirectory(libs)
+# add_subdirectory(apps)

README.md

@@ -37,8 +37,8 @@ The git commit should describe what is done and why certain choices were made.
 The title of the commit should always end with (AI), to indicate that it was written by an AI.
 Once a task is completed, it should be checked off.
 
-- [ ] Create directory structure
-- [ ] Create initial build system
+- [x] Create directory structure
+- [x] Create initial build system
 - [ ] Setup a simple kernel that writes `Hello, world` to Qemu debug port
 - [ ] Update the build system to create both ISO and Floppy images. Verify these work using a test script. The standard CMake build target should automatically generate both images.
 - [ ] Update the kernel to correctly setup the GDT

src/CMakeLists.txt

@@ -0,0 +1,13 @@
+cmake_minimum_required(VERSION 3.16)
+
+add_executable(kernel 
+    kernel.c
+)
+
+# Use our custom linker script
+target_link_options(kernel PRIVATE -T ${CMAKE_CURRENT_SOURCE_DIR}/linker.ld)
+
+target_include_directories(kernel PRIVATE 
+    ${CMAKE_SOURCE_DIR}/vendor
+    ${CMAKE_SOURCE_DIR}/include # If created later
+)

src/kernel.c

@@ -0,0 +1,3 @@
+void _start() {
+    while(1) {}
+}

src/linker.ld

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