Implement basic build script in python

Honestly reading the code is the best docs

.cargo/config.toml

@@ -0,0 +1,2 @@
+[build]
+target-dir="build/"

.gitignore

@@ -0,0 +1,2 @@
+/build
+/linux/.config.old

.gitmodules

@@ -3,3 +3,7 @@
 	path = linux/kernel
     url = https://github.com/torvalds/linux.git
     shallow = true
+[submodule "linux/busybox"]
+	path = linux/busybox
+    url = https://git.busybox.net/busybox/
+    shallow = true

Cargo.lock

@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "embnux-init"
+version = "0.1.0"

Cargo.toml

@@ -1,3 +1,3 @@
 [workspace]
 resolver="2"
-members=[]
+members=["embnux-init"]

Makefile

@@ -1,22 +1,27 @@
 MAKEFILE_DIR := $(dir $(abspath $(lastword $(MAKEFILE_LIST))))
 
 BUILD_DIR ?= $(MAKEFILE_DIR)build
-ARCH ?= x86
+ARCH ?= x86_64
 KERNEL_FILE_NAME ?= bzImage
+INITRAMFS_FILE = $(BUILD_DIR)/linux/initramfs.cpio
+KERNEL_FILE = $(BUILD_DIR)/linux/kernel/arch/$(ARCH)/boot/$(KERNEL_FILE_NAME)
 
+export BUILD_DIR
 export ARCH
 export KERNEL_FILE_NAME
 
-KERNEL_PATH = $(BUILD_DIR)/arch/$(ARCH)/boot/$(bzImage)
+kernel: 
+	$(MAKE) -C $(MAKEFILE_DIR)/linux kernel
 
-all: $(KERNEL_PATH)
+initramfs:
+	$(MAKE) -C $(MAKEFILE_DIR)/linux initramfs -B
 
 
-$(KERNEL_PATH):
-	@mkdir -p $(BUILD_DIR)/linux/kernel
-	cp $(MAKEFILE_DIR)/linux/.config $(BUILD_DIR)/linux/kernel/.config
-	$(MAKE) -C $(MAKEFILE_DIR)/linux/kernel O=$(BUILD_DIR)/linux/kernel
+kernel-config:
+	$(MAKE) -C $(MAKEFILE_DIR)/linux kernel-config
 
+qemu:
+	qemu-system-x86_64 -kernel $(KERNEL_FILE) -initrd $(INITRAMFS_FILE) -append "rdinit=/usr/sbin/init console=ttyS0" -serial mon:stdio
 
 
 clean:

embnux-init/Cargo.toml

@@ -0,0 +1,6 @@
+[package]
+name = "embnux-init"
+version = "0.1.0"
+edition = "2024"
+
+[dependencies]

embnux-init/src/main.rs

@@ -0,0 +1,3 @@
+fn main() {
+    println!("Hello, world!");
+}

linux/.kernel-config.old

@@ -2705,6 +2705,7 @@ CONFIG_SERIAL_8250_PERICOM=y
 # CONFIG_SERIAL_UARTLITE is not set
 CONFIG_SERIAL_CORE=y
 CONFIG_SERIAL_CORE_CONSOLE=y
+CONFIG_CONSOLE_POLL=y
 # CONFIG_SERIAL_JSM is not set
 # CONFIG_SERIAL_LANTIQ is not set
 # CONFIG_SERIAL_SCCNXP is not set
@@ -5182,7 +5183,13 @@ CONFIG_DEBUG_FS_ALLOW_ALL=y
 # CONFIG_DEBUG_FS_DISALLOW_MOUNT is not set
 # CONFIG_DEBUG_FS_ALLOW_NONE is not set
 CONFIG_HAVE_ARCH_KGDB=y
-# CONFIG_KGDB is not set
+CONFIG_KGDB=y
+CONFIG_KGDB_HONOUR_BLOCKLIST=y
+CONFIG_KGDB_SERIAL_CONSOLE=y
+# CONFIG_KGDB_TESTS is not set
+# CONFIG_KGDB_LOW_LEVEL_TRAP is not set
+# CONFIG_KGDB_KDB is not set
+CONFIG_ARCH_HAS_EARLY_DEBUG=y
 CONFIG_ARCH_HAS_UBSAN=y
 # CONFIG_UBSAN is not set
 CONFIG_HAVE_ARCH_KCSAN=y

linux/Makefile

@@ -1,4 +1,67 @@
+MAKEFILE_DIR := $(dir $(abspath $(lastword $(MAKEFILE_LIST))))
+
+BUILD_DIR ?= $(MAKEFILE_DIR)build
+ARCH ?= x86
+KERNEL_FILE_NAME ?= bzImage
+
+KERNEL_PATH = $(BUILD_DIR)/arch/$(ARCH)/boot/$(bzImage)
+KERNEL_BUILD_DIR=$(BUILD_DIR)/linux/kernel
+
+BUSYBOX_BUILD_DIR=$(BUILD_DIR)/linux/busybox
+BUSYBOX_BUILD_FILE=$(BUSYBOX_BUILD_DIR)/busybox
+
+INITRAMFS_DIR=$(BUILD_DIR)/linux/initramfs
+INITRAMFS_FILE_TMP=$(BUILD_DIR)/linux/initramfs.cpio
+INITRAMFS_FILE=$(BUILD_DIR)/linux/initramfs.cpio.gz
 
 
 
+.PHONY: initramfs initramfs_initiial initramfs_clean busybox all kernel __busybox_install
+
+all:  $(INITRAMFS_FILE)
+initramfs:initramfs_clean initramfs_initiial __busybox_install $(INITRAMFS_FILE)
+kernel: $(KERNEL_PATH)
+busybox: $(BUSYBOX_BUILD_FILE)
+
+$(KERNEL_PATH):
+	@mkdir -p $(KERNEL_BUILD_DIR)
+	$(MAKE) -C $(MAKEFILE_DIR)/kernel O=$(KERNEL_BUILD_DIR) KCONFIG_CONFIG="$(MAKEFILE_DIR)/.kernel-config"
+
+kernel-config:
+	$(MAKE) -C $(MAKEFILE_DIR)/kernel O=$(KERNEL_BUILD_DIR) KCONFIG_CONFIG="$(MAKEFILE_DIR)/.kernel-config" menuconfig
+
+$(BUSYBOX_BUILD_FILE):
+	@mkdir -p $(BUSYBOX_BUILD_DIR)
+	cp $(MAKEFILE_DIR)/.busybox-config $(BUSYBOX_BUILD_DIR)/.config
+	$(MAKE) -C $(MAKEFILE_DIR)/busybox O=$(BUSYBOX_BUILD_DIR) KCONFIG_CONFIG="$(MAKEFILE_DIR)/.busybox-config"
+
+__busybox_install:
+	$(MAKE) -C $(MAKEFILE_DIR)/busybox O=$(BUSYBOX_BUILD_DIR) KCONFIG_CONFIG="$(MAKEFILE_DIR)/.busybox-config" CONFIG_PREFIX=$(INITRAMFS_DIR) install 
+
+
+
+$(INITRAMFS_FILE): initramfs_clean initramfs_initiial __busybox_install
+	find $(INITRAMFS_DIR) | cpio -o -H newc > $(INITRAMFS_FILE_TMP)
+	# gzip -f $(INITRAMFS_FILE_TMP)
+
+initramfs_clean:
+	@rm -rf $(INITRAMFS_DIR)
+
+initramfs_initiial: #$(BUSYBOX_BUILD_FILE)
+	mkdir -p $(INITRAMFS_DIR)
+	mkdir -p $(INITRAMFS_DIR)/{etc,mnt,proc,run,srv,tmp,var,boot,dev,home,media,opt,root,sbin,sys,usr/bin,usr/lib}
+
+	bash -c "pushd $(INITRAMFS_DIR); ln -s usr/bin bin; popd"
+	bash -c "pushd $(INITRAMFS_DIR); ln -s usr/lib lib; popd"
+
+
+	echo "#!/bin/sh" >> $(INITRAMFS_DIR)/init
+	echo "mount -t proc none /proc" >> $(INITRAMFS_DIR)/init
+	echo "mount -t sysfs none /sys" >> $(INITRAMFS_DIR)/init
+	echo "echo 'Successfully booted'" >> $(INITRAMFS_DIR)/init
+	echo "exec /bin/sh" >> $(INITRAMFS_DIR)/init
+
+	chmod +x $(INITRAMFS_DIR)/init
+	chmod +x $(INITRAMFS_DIR)/sbin/init
+
 

pyproject.toml

@@ -0,0 +1,4 @@
+[tool.pylsp.plugins.pycodestyle]
+enabled = true
+ignore = ["E501", "W291"]  # ignore line length & trailing whitespace
+

x.py

@@ -0,0 +1,258 @@
+#!/usr/bin/env python
+
+import sys
+import subprocess
+import threading
+import os
+from datetime import datetime
+
+__FILENAME = ""
+
+MAX_JOBS = max(1, len(os.sched_getaffinity(0)) - 2)
+TS_VRB = 2
+CWD = os.path.dirname(os.path.abspath(__file__))
+
+BUILD_D = f"{CWD}/build"
+INITRAMFS_DIR = f"{BUILD_D}/linux/initramfs"
+INITRAMFS_FILE_TMP = f"{BUILD_D}/linux/initramfs.cpio"
+INITRAMFS_FILE = f"{BUILD_D}/linux/initramfs.cpio.gz"
+KERNEL_FILE = F"{BUILD_D}/linux/KernelImage"
+
+
+def shift(arr):
+    if not arr:
+        return None  # or raise IndexError if you prefer
+    return arr.pop(0)
+
+
+def timestamp(dt=datetime.now(), fmt="hours"):
+    return f"{dt.hour:0>2}:{dt.minute:0>2}:{dt.second:0>2}"
+
+
+def run(*cmds, parallel=False, tag=None, interactive=False, chdir=None):
+    threads = []
+
+    def run_single(cmd, tag, chdir):
+        env = os.environ.copy()
+        env["MAKE_TERMOUT"] = "true"
+        env["MAKE_TERMERR"] = "true"
+        start_time = datetime.now()
+        print(f"{f"{timestamp(start_time)} | " if TS_VRB > 0 else ""}CMD: {cmd}")
+        with subprocess.Popen(
+            cmd, shell=True,
+            stdout=None if interactive else subprocess.PIPE,
+            stderr=None if interactive else subprocess.STDOUT,
+            cwd=chdir if chdir else None,
+            # text=None if interactive else True,
+        ) as proc:
+            if not interactive:
+                for line in proc.stdout:
+                    dt = datetime.now()
+                    if tag:
+                        print(f"{f"{timestamp(dt)} | " if TS_VRB >
+                              0 else ""}stdout ({tag}): ", flush=True, end='')
+                    else:
+                        print(f"{f"{timestamp(dt)} | " if TS_VRB >
+                              0 else ""}stdout: ", flush=True, end='')
+                    sys.stdout.buffer.write(line)
+                    sys.stdout.buffer.flush()
+            proc.wait()
+            if proc.returncode != 0:
+                print(f"ERROR: Command '{
+                      cmd}' exited with code {proc.returncode}")
+                exit(1)
+    for i, command in enumerate(cmds):
+
+        current_tag = tag if len(cmds) <= 1 else (
+            f"{tag}-{i}" if tag else None)
+        if parallel:
+            t = threading.Thread(
+                target=run_single, args=(command, current_tag, chdir))
+            t.start()
+            threads.append(t)
+        else:
+            run_single(command, current_tag, chdir)
+
+    for t in threads:
+        t.join()
+
+
+def todo(reason):
+    print(f"ERROR: Unimplemented {reason}")
+    exit(1)
+
+
+def cmd_configure(args):
+
+    def cmd_help():
+        print(f"Usage: {__FILENAME} configure [component]")
+        print("Components:")
+        print("  help      - Show this help")
+        print("  kernel    - The linux kernel")
+        print("  busybox   - Busybox")
+
+    # $(MAKE) -C $(MAKEFILE_DIR)/kernel O=$(KERNEL_BUILD_DIR) KCONFIG_CONFIG="$(MAKEFILE_DIR)/.kernel-config" menuconfig
+    subc = shift(args)
+    if not subc or subc == "help":
+        cmd_help()
+        exit(1)
+    elif subc == "kernel":
+        run(f"make -C {CWD}/linux/kernel O={BUILD_D}/linux/kernel KCONFIG_CONFIG='{
+            CWD}/linux/.kernel-config' menuconfig", interactive=True)
+    elif subc == "busybox":
+        run(f"make -C {CWD}/linux/busybox O={BUILD_D}/linux/busybox KCONFIG_CONFIG='{
+            CWD}/linux/.busybox-config' menuconfig", interactive=True)
+    else:
+        print(f"ERROR: Unknown component {subc}")
+        cmd_help()
+        exit(1)
+
+
+def cmd_build(args):
+    def cmd_help():
+        print(f"Usage: {__FILENAME} build [component]")
+        print("Components:")
+        print("  help        - Show this help")
+        print("  all         - Builds everything")
+        print("  linux       - Everything bellow")
+        print("    kernel    - The linux kernel")
+        print("    busybox   - Busybox")
+        print("    initramfs - Busybox")
+        print("  rust        - Builds all of the rust components")
+        print("  img         - Rebuilds the image")
+
+    def build_init():
+        run(
+            f"mkdir -p {BUILD_D}/linux/kernel",
+            f"mkdir -p {BUILD_D}/linux/busybox",
+            parallel=True
+        )
+
+    def build_kernel(args):
+        run(f"make -C {CWD}/linux/kernel O={BUILD_D}/linux/kernel KCONFIG_CONFIG='{
+            CWD}/linux/.kernel-config' -j{MAX_JOBS}", tag="kernel")
+        run(f"cp {
+            BUILD_D}/linux/kernel/arch/x86_64/boot/bzImage {KERNEL_IMAGE}")
+
+    def build_busybox(args):
+        run(
+            f"cp {CWD}/linux/.busybox-config {
+                BUILD_D}/linux/busybox/.config",
+            f"make -C {CWD}/linux/busybox O={BUILD_D}/linux/busybox KCONFIG_CONFIG='{
+                CWD}/linux/.busybox-config' -j{MAX_JOBS}",
+            tag="busybox"
+        )
+
+    def build_rust(args):
+        todo("build_rust")
+
+    def build_initramfs(args):
+        run(f"rm -rf {INITRAMFS_DIR}")
+        run(f"mkdir -p {INITRAMFS_DIR}/{{etc,mnt,proc,run,srv,tmp,var,boot,dev,home,media,opt,root,sbin,sys,usr/bin,usr/lib}}")
+
+        run("ln -s usr/bin bin",
+            "ln -s usr/lib lib",
+            chdir=INITRAMFS_DIR)
+
+        init_script =\
+            "#!/bin/sh\\n" +\
+            "mount -t proc none /proc\\n" +\
+            "mount -t sysfs none /sys\\n" +\
+            "echo 'Successfully booted'\\n" +\
+            "exec /bin/sh\\n"
+
+        run(f"echo {init_script} > {INITRAMFS_DIR}/init")
+
+        # run(
+        #    f"chmod +x {INITRAMFS_DIR}/init",
+        #    f"chmod +x {INITRAMFS_DIR}/sbin/init"
+        # )
+
+        run(
+            f"make -C {CWD}/linux/busybox O={BUILD_D}/linux/busybox KCONFIG_CONFIG='{
+                CWD}/linux/.busybox-config' -j{MAX_JOBS} CONFIG_PREFIX={INITRAMFS_DIR} install",
+        )
+
+        run(
+            f"find {INITRAMFS_DIR} | cpio -o -H newc > {INITRAMFS_FILE_TMP}",
+            f"gzip -f {INITRAMFS_FILE_TMP}"
+        )
+
+    def build_image(args):
+        # for the later bootable.img or whatever file
+        todo("build_image")
+
+    cmd = shift(args)
+
+    if not cmd or cmd == "help":
+        cmd_help()
+        exit(1)
+    elif cmd == "all":
+        build_init()
+        build_kernel(args)
+        build_busybox(args)
+        build_rust(args)
+        build_image(args)
+    elif cmd == "linux":
+        build_init()
+        build_kernel(args)
+        build_busybox(args)
+    elif cmd == "kernel":
+        build_init()
+        build_kernel(args)
+    elif cmd == "busybox":
+        build_init()
+        build_busybox(args)
+    elif cmd == "rust":
+        build_init()
+        build_rust(args)
+    elif cmd == "img":
+        build_init()
+        build_image(args)
+    elif cmd == "initramfs":
+        build_initramfs(args)
+    else:
+        print(f"ERROR: Unknown component '{cmd}'")
+        cmd_help()
+        exit(1)
+
+def cmd_qemu(args):
+    run(f"qemu-system-x86_64 -kernel {KERNEL_FILE} -initrd {INITRAMFS_FILE} -append \"rdinit=/usr/sbin/init console=ttyS0\" -serial mon:stdio")
+
+
+AVAILABLE_SUBCOMMANDS = {
+    "help": help,
+    "configure": cmd_configure,
+    "build": cmd_build,
+    "qemu": cmd_qemu,
+}
+
+
+def help():
+    print(f"Usage: {__FILENAME} [subcommand]")
+    print("Subcommands:")
+    print("  help      - Show this help")
+    print("  configure - Configure components")
+    print("  build     - Compile/build components")
+    print("  qemu      - Run a vm with the current build")
+
+
+if __name__ == "__main__":
+    args = sys.argv
+    __FILENAME = shift(args)
+
+    cmd = shift(args)
+
+    if not cmd:
+        help()
+        exit(1)
+
+    cmd_v = AVAILABLE_SUBCOMMANDS[cmd]
+    if not cmd_v:
+        print(f"ERROR: Unknown subcommand '{cmd}'")
+        help()
+        exit(1)
+
+    (cmd_v)(args)
+
+    exit(0)