HAL Howto

With HAL and Ivman and pmount, you can have devices like CD-ROMs and USB flash sticks be automatically mounted and added to your panel or desktop. When you unmount it the mountpoint will be removed from your panel.

• HAL is a hardware abstraction layer that keeps track of your hardware, both internal and removable. It’s like a database that adds information from the hardware and from .fdi files, and it can also call other programs when certain events happens.
• Udev tells HAL when hardware is added or removed and replaces Hotplug in this functionality.
• Ivman is a volume manager that can be set up to automount removable media, and to do all kinds of other stuff. It reacts when media is inserted or removed, or when a property of any device is changed.
• Dbus is an IPC service that lets all these components communicate with each other.

Setup

The following was tried with Udev 070, HAL 0.5.4, DBus 0.50, Ivman 0.6.4, and Pmount 0.9.3. We are going to set things up so that Ivman is run as root and handles the automounting under /Mount/Media , with the help of pmount. Then users can run their own instances of Ivman too, to handle desktop specific stuff (like adding devices to the panel).

• You need to be running Udev and DBus, make sure that’s the case and that the DBus system bus is started at boot. (Use StartTask messagebus)

• You also need a recent kernel and glibc compiled against recent headers. This was tested with Glibc 2.3.5 with NPTL compiled against Linux-Libc-Headers 2.6.12.0

• Install HAL, Pmount and Ivman:

] Compile hal
...
] Compile pmount
...
] Compile ivman
...

Pmount should be patched with http://kymatica.com/stuff/pmount-0.9.3-lijon.patch and HAL should be patched with http://kymatica.com/stuff/hal-0.5.4-lijon.patch (These patches should be included with the recipes, together with the small patch that escapes the $hal.volume.mount_point$ in ivmans src/manager.c:619)

• Make sure there is nothing in /System/Settings/hal/device.d that does any mounting, becouse we want ivman to handle the mounting! (Actually I don’t think device.d works in HAL 0.5.4 since they moved to info.callouts.* instead…)

• Make sure there is a haldaemon system group and user, and a plugdev group. Add all users that should be able to access and unmount removable media to the plugdev group. Note that users must log out and in again for the group changes to take effect

• Start HAL as root:

] StartTask hald

• Start Ivman as root:

] ivman

Exec "Starting D-Bus system bus..."             messagebus
Exec "Starting HAL daemon..."                   StartTask hald 
Exec "Starting Volume Manager..."               ivman

• Make sure Ivman is started as your user too: Add this script in your AutoStart folder:

#!/bin/sh
exec 1>&2
echo -n "Launching volume manager... "
if ps -C ivman -o user | grep -q $USER
  then
    echo "Already running."
    exit
  else
    echo "OK"
    exec ivman
fi

• Disable mounting with usermode ivman, or else there will be problems if more than one user is logged in and running ivman at the same time… We want the root ivman to handle mounting. In ~/.ivman/IvmConfigActions.xml, comment out this section:

Ivman rules to add devices to your ROX panel

• Create a script named ~/bin/rox.panelput and make it executable:

#!/bin/sh
### Change "Top" below to the panel you want your devices on...
rox --RPC << EOF
<?xml version="1.0"?>
<env:Envelope xmlns:env="http://www.w3.org/2001/12/soap-envelope">
<env:Body xmlns="http://rox.sourceforge.net/SOAP/ROX-Filer">
<Panel$1>
<Side>Top</side>
<Path>$2</path>
</panel$1>
</env:body>
</env:envelope>
EOF

• And here comes the ivman rule, which should be inserted in your ~/.ivman/IvmConfigProperties.xml (this files is created first time you run ivman as a user)

<ivm:Match name="ivm.mountable" value="true">
<ivm:Property name="hal.volume.is_mounted">
<ivm:Action value="true" exec='rox.panelput Add "$hal.volume.mount_point$"' />
<ivm:Action value="false" exec='rox.panelput Remove "$hal.volume.mount_point$"' />
</ivm:property>
</ivm:match>

A nice ~/bin/eject script:

This lets you unmount your media and also FUSE mountpoints with the Eject entry on the right-click menu on mountpoints. Don’t forget to make the script executable.

#!/bin/sh
pumount "$1" 2>/dev/null || fusermount -u "$1" 2>/dev/null ||
echo "Could not unmount with pumount or fusermount -u" >&2

More patches

Spaces in mountpoint names

Ivman 0.6.5 and earlier have the problem that mountpoints are not enclosed by quotes when passed as arg to pmount. So if a inserted media has spaces in the desired mount point, pmount will fail! look in ivmans src/manager.c:619 and put " around the $hal.volume.desiredmountpoint$ thing… This bug was fixed upstream in Ivman 0.6.6, thus this workaround is no longer required.

Better mountpoint names

At least for me, my CD-ROM’s got mounted as /media/hde and stuff like that, this patch to /System/Index/share/hal/fdi/policy/10osvendor/10-storage-policy.fdi fixed it so that media is mounted with the volume label as mountpoint:

-       <match key="@block.storage_device:storage.no_partitions_hint" bool="false">
-
+
<merge key="volume.policy.should_mount" type="bool">true</merge>
<merge key="volume.policy.mount_filesystem" type="copy_property">volume.fstype</merge>

@@ -173,7 +172,7 @@
<merge key="volume.policy.should_mount" type="bool">true</merge>
</match>
</match>
-       </match>
+
</match>
</match>

Note that you can put a copy of this file under /System/Settings/hal/fdi/policy and patch that one instead.

Making different types of media get different icons

With ROX, it’s also possible to have the inserted media get an icon that represents the type of media inserted.

• Patch rox-filer to add SOAP calls for setting icons: http://kymatica.com/stuff/rox-2.3-iconsoap.patch

• Add this /System/Settings/hal/fdi/information/10-usb-flash.fdi to detect usb flash sticks:

    <?xml version="1.0" encoding="UTF-8"?>
    <deviceinfo version="0.2">
    <device>
    <match key="@block.storage_device:storage.bus" string="usb">
    <match key="info.category" string="volume">
    <merge key="volume.is_usb_storage" type="bool">true</merge>
    </match>
    </match>
    </device>
    </deviceinfo>

• Change your ~/.ivman/IvmConfigProperties.xml rule to this:

<ivm:Match name="hal.volume.is_usb_storage" value="true">
<ivm:Property name="hal.volume.is_mounted">
<ivm:Action value="true" exec='rox.seticon Set "$hal.volume.mount_point$" $HOME/.ivman/usb.png' />
<ivm:Action value="false" exec='rox.seticon Unset "$hal.volume.mount_point$"' />
</ivm:property>
</ivm:match>

<ivm:Match name="hal.volume.is_disc" value="true">
<ivm:Property name="hal.volume.is_mounted">
<ivm:Action value="true" exec='rox.seticon Set "$hal.volume.mount_point$" $HOME/.ivman/cdr.png' />
<ivm:Action value="false" exec='rox.seticon Unset "$hal.volume.mount_point$"' />
</ivm:property>
</ivm:match>

<ivm:Property name="hal.volume.is_mounted">
<ivm:Action value="true" exec='rox.panelput Add "$hal.volume.mount_point$"' />
<ivm:Action value="false" exec='rox.panelput Remove "$hal.volume.mount_point$"' />
</ivm:property>
</ivm:match>

• Create this script in ~/bin/rox.seticon and make it executable:

rox --RPC << EOF
<?xml version="1.0"?>
<env:Envelope xmlns:env="http://www.w3.org/2001/12/soap-envelope">
<env:Body xmlns="http://rox.sourceforge.net/SOAP/ROX-Filer">
<$1Icon>
<Path>$2</path>
<Icon>$3</icon>
</$1icon>
</env:body>
</env:envelope>
    EOF

• And put some icons for other.png, cdr.png and usb.png in ~/.ivman/ and you’re done!