Implement basic build script in python

x.py

@@ -13,6 +13,10 @@ 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):
@@ -25,10 +29,10 @@ 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):
+def run(*cmds, parallel=False, tag=None, interactive=False, chdir=None):
     threads = []
 
-    def run_single(cmd, tag):
+    def run_single(cmd, tag, chdir):
         env = os.environ.copy()
         env["MAKE_TERMOUT"] = "true"
         env["MAKE_TERMERR"] = "true"
@@ -38,6 +42,7 @@ def run(*cmds, parallel=False, tag=None, interactive=False):
             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:
@@ -62,11 +67,11 @@ def run(*cmds, parallel=False, tag=None, interactive=False):
             f"{tag}-{i}" if tag else None)
         if parallel:
             t = threading.Thread(
-                target=run_single, args=(command, current_tag))
+                target=run_single, args=(command, current_tag, chdir))
             t.start()
             threads.append(t)
         else:
-            run_single(command, current_tag)
+            run_single(command, current_tag, chdir)
 
     for t in threads:
         t.join()
@@ -112,6 +117,7 @@ def cmd_build(args):
         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")
 
@@ -125,6 +131,8 @@ def cmd_build(args):
     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(
@@ -138,6 +146,38 @@ def cmd_build(args):
     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")
@@ -169,16 +209,22 @@ def cmd_build(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
+    "build": cmd_build,
+    "qemu": cmd_qemu,
 }
 
 
@@ -188,6 +234,7 @@ def help():
     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__":