Update VBox Additions code with some minor changes (especially for ca…

…che-ability)

Also, this includes a hacky init script that bfirsh gets to take all the credit for that tries to mount `/Users` and/or `/c/Users`, since we can't run `VBoxService` proper (thanks to hairy issues with 32bit userspace of TCL; good times).

Dockerfile

@@ -47,7 +47,6 @@ RUN jobs=$(nproc); \
 # The post kernel build process
 
 ENV ROOTFS          /rootfs
-ENV VBOX_VERSION    4.3.12
 ENV TCL_REPO_BASE   http://tinycorelinux.net/5.x/x86
 ENV TCZ_DEPS        iptables \
                     iproute2 \
@@ -109,18 +108,6 @@ RUN cd /linux-kernel && \
 # Prepare the ISO directory with the kernel
 RUN cp -v /linux-kernel/arch/x86_64/boot/bzImage /tmp/iso/boot/vmlinuz64
 
-# Build VBox guest additions
-RUN mkdir -p /vboxguest && \
-    cd /vboxguest && \
-    curl -L -o vboxguest.iso http://download.virtualbox.org/virtualbox/${VBOX_VERSION}/VBoxGuestAdditions_${VBOX_VERSION}.iso && \
-    7z x vboxguest.iso -ir'!VBoxLinuxAdditions.run' && \
-    sh VBoxLinuxAdditions.run --noexec --target . && \
-    mkdir x86 && cd x86 && tar xvjf ../VBoxGuestAdditions-x86.tar.bz2 && cd .. && \
-    mkdir amd64 && cd amd64 && tar xvjf ../VBoxGuestAdditions-amd64.tar.bz2 && cd .. && \
-    cd amd64/src/vboxguest-${VBOX_VERSION} && KERN_DIR=/linux-kernel/ make && cd ../../.. && \
-    cp amd64/src/vboxguest-${VBOX_VERSION}/*.ko $ROOTFS/lib/modules/$KERNEL_VERSION-tinycore64 && \
-    mkdir -p $ROOTFS/sbin && cp x86/lib/VBoxGuestAdditions/mount.vboxsf $ROOTFS/sbin/
-
 # Download the rootfs, don't unpack it though:
 RUN curl -L -o /tcl_rootfs.gz $TCL_REPO_BASE/release/distribution_files/rootfs.gz
 
@@ -132,13 +119,35 @@ RUN for dep in $TCZ_DEPS; do \
         rm -f /tmp/$dep.tcz ;\
     done
 
-# Make sure that all the modules we might have added are recognized
-RUN depmod -a -b $ROOTFS $KERNEL_VERSION-tinycore64
-
 # get generate_cert
 RUN curl -L -o $ROOTFS/usr/local/bin/generate_cert https://github.com/SvenDowideit/generate_cert/releases/download/0.1/generate_cert-0.1-linux-386/ && \
     chmod +x $ROOTFS/usr/local/bin/generate_cert
 
+# Build VBox guest additions
+# For future reference, we have to use x86 versions of several of these bits because TCL doesn't support ELFCLASS64
+# (... and we can't use VBoxControl or VBoxService at all because of this)
+ENV VBOX_VERSION 4.3.16
+RUN mkdir -p /vboxguest && \
+    cd /vboxguest && \
+    \
+    curl -L -o vboxguest.iso http://download.virtualbox.org/virtualbox/${VBOX_VERSION}/VBoxGuestAdditions_${VBOX_VERSION}.iso && \
+    7z x vboxguest.iso -ir'!VBoxLinuxAdditions.run' && \
+    rm vboxguest.iso && \
+    \
+    sh VBoxLinuxAdditions.run --noexec --target . && \
+    mkdir amd64 && tar -C amd64 -xjf VBoxGuestAdditions-amd64.tar.bz2 && \
+    mkdir x86 && tar -C x86 -xjf VBoxGuestAdditions-x86.tar.bz2 && \
+    rm VBoxGuestAdditions*.tar.bz2 && \
+    \
+    KERN_DIR=/linux-kernel/ make -C amd64/src/vboxguest-${VBOX_VERSION} && \
+    cp amd64/src/vboxguest-${VBOX_VERSION}/*.ko $ROOTFS/lib/modules/$KERNEL_VERSION-tinycore64/ && \
+    \
+    mkdir -p $ROOTFS/sbin && \
+    cp x86/lib/VBoxGuestAdditions/mount.vboxsf $ROOTFS/sbin/
+
+# Make sure that all the modules we might have added are recognized (especially VBox guest additions)
+RUN depmod -a -b $ROOTFS $KERNEL_VERSION-tinycore64
+
 COPY VERSION $ROOTFS/etc/version
 RUN cp -v $ROOTFS/etc/version /tmp/iso/version
 

README.md

@@ -155,6 +155,40 @@ the "samba" container that refers to it by name. So, in this example, if you
 were on OS-X you now have /Volumes/data and /data in container being shared. You
 can change the paths as needed.
 
+##### VirtualBox Guest Additions
+
+Alternatively, Boot2Docker includes the VirtualBox Guest Additions built in for
+the express purpose of using VirtualBox folder sharing.
+
+The first of the following share names that exists (if any) will be
+automatically mounted at the location specified:
+
+1. `Users` share at `/Users`
+2. `/Users` share at `/Users`
+3. `c/Users` share at `/c/Users`
+4. `/c/Users` share at `/c/Users`
+5. `c:/Users` share at `/c/Users`
+
+If some other path or share is desired, it can be mounted at run time by doing
+something like:
+
+```console
+$ mount -t vboxsf -o uid=1000,gid=50 your-other-share-name /some/mount/location
+```
+
+It is also important to note that in the future, the plan is to have any share
+which is created in VirtualBox with the "automount" flag turned on be mounted
+during boot at the directory of the share name (ie, a share named `home/jsmith`
+would be automounted at `/home/jsmith`).
+
+In case it isn't already clear, the Linux host support here is currently hazy.
+You can share your `/home` or `/home/jsmith` directory as `Users` or one of the
+other supported automount locations listed above, but note that you will then
+need to manually convert your `docker run -v /home/...:...` bind-mount host
+paths accordingly (ie, `docker run -v /Users/...:...`).  As noted in the
+previous paragraph however, this is likely to change in the future as soon as a
+more suitable/scalable solution is found and implemented.
+
 #### Customize
 
 The `boot2docker` management tool allows you to customise many options from both

rootfs/rootfs/bootscript.sh

@@ -39,6 +39,9 @@ if grep -q '^docker:' /etc/passwd; then
     fi
 fi
 
+# Automount Shared Folders (VirtualBox, etc.)
+/etc/rc.d/automount-shares
+
 # Configure SSHD
 /etc/rc.d/sshd
 

rootfs/rootfs/etc/rc.d/automount-shares

@@ -0,0 +1,45 @@
+#!/bin/sh
+set -e
+
+# TODO add more magic like sshfs share setup here <3
+
+# VirtualBox Guest Additions
+# - this will bail quickly and gracefully if we're not in VBox
+if modprobe vboxguest &> /dev/null && modprobe vboxsf &> /dev/null; then
+	mountOptions='defaults'
+	if grep -q '^docker:' /etc/passwd; then
+		mountOptions="${mountOptions},uid=$(id -u docker),gid=$(id -g docker)"
+	fi
+
+	# try mounting "$name" (which defaults to "$dir") at "$dir",
+	# but quietly clean up empty directories if it fails
+	try_mount_share() {
+		dir="$1"
+		name="${2:-$dir}"
+
+		mkdir -p "$dir" 2>/dev/null
+		if ! mount -t vboxsf -o "$mountOptions" "$name" "$dir" 2>/dev/null; then
+			rmdir "$dir" 2>/dev/null || true
+			while [ "$(dirname "$dir")" != "$dir" ]; do
+				dir="$(dirname "$dir")"
+				rmdir "$dir" 2>/dev/null || break
+			done
+
+			return 1
+		fi
+
+		return 0
+	}
+
+	# bfirsh gets all the credit for this hacky workaround :)
+	try_mount_share /Users 'Users' \
+		|| try_mount_share /Users \
+		|| try_mount_share /c/Users 'c/Users' \
+		|| try_mount_share /c/Users \
+		|| try_mount_share /c/Users 'c:/Users' \
+		|| true
+	# TODO replace this whole hacky bit with VBoxService --only-automount
+	# (the problem with that being that we can't run VBoxService because the
+	#  32bit VBoxService won't work with the 64bit kernel modules, but the 64bit
+	#  VBoxService won't work with our 32bit userspace; good times)
+fi