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-rwxr-xr-xmkinitrd/mkinitramfs.sh81
1 files changed, 81 insertions, 0 deletions
diff --git a/mkinitrd/mkinitramfs.sh b/mkinitrd/mkinitramfs.sh
new file mode 100755
index 0000000..9e32cee
--- /dev/null
+++ b/mkinitrd/mkinitramfs.sh
@@ -0,0 +1,81 @@
+#!/bin/sh
+
+BUILD=/tmp/ramfs
+OUT=${1-/boot/initramfs-linux.img}
+
+
+# create base directory structure
+printf "creating directories..."
+
+[ -e $BUILD ] && rm -rf $BUILD
+mkdir -p $BUILD/tmp
+
+cd $BUILD
+mkdir -p bin dev etc lib proc run sbin sys usr
+mkdir -p lib/firmware lib/modules lib/udev
+mkdir -p etc/modprobe.d etc/udev
+
+ln -s lib lib64
+ln -s ../bin usr/bin
+ln -s ../sbin usr/sbin
+printf "OK\n"
+
+# copy binaries
+printf "populating /bin..."
+for b in dash cat cp dd killall kmod ln ls mkdir \
+ mknod mount rm sed sleep umount uname \
+ basename readlink printf echo udevadm; do
+ cp -a /bin/$b bin/
+done
+ln -s dash bin/sh
+ln -s kmod bin/insmod
+ln -s kmod bin/lsmod
+printf "OK\n"
+
+# create nodes for udev to mount
+printf "creating nodes..."
+mknod -m 600 dev/console c 5 1
+mknod -m 666 dev/null c 1 3
+printf "OK\n"
+
+# Copy udev configuration
+printf "configuring udev..."
+cp /etc/udev/udev.conf etc/udev/
+cp -r /etc/udev/rules.d etc/udev/
+cp -r /lib/udev/* lib/udev/
+printf "OK\n"
+
+# set module order
+touch etc/modprobe.d/modprobe.conf
+
+# copy the init script
+printf "installing init script..."
+cp /sbin/initramfs-init sbin/init
+printf "OK\n"
+
+# copy required libraries
+printf "populating /lib..."
+for l in c acl attr blkid cap kmod lzma mount ncursesw readline z curses history zstd; do
+ cp /lib/lib$l.so lib/
+done
+ln -s libc.so /ld-musl-$(uname -m).so.1
+printf "OK\n"
+
+# copy any firmware
+[ -d /lib/firmware ] && {
+ printf "installing firmware..."
+ cp -r /lib/firmware/* lib/firmware/
+ printf "OK\n"
+}
+
+# copy any modules
+printf "installing modules..."
+cp -r /lib/modules/* lib/modules/
+printf "OK\n"
+
+# create the initramfs image
+printf "creating initramfs image..."
+find ./ | cpio -o -H newc | gzip -9 > $OUT
+printf "OK\n"
+
+printf "Written initramfs image to $OUT\n"