GUESTFSD_EXT_CMD was used by OpenSUSE to track which external commands
are run by the daemon and package those commands into the appliance.
It is no longer used by recent SUSE builds, so remove it.
Thanks: Pino Toscano, Olaf Hering.
guestfsd calls many different tools. Keeping track of all of them is
error prone. This patch introduces a new helper macro to put the command
string into its own ELF section:
GUESTFSD_EXT_CMD(C_variable, command_name);
This syntax makes it still possible to grep for used command names.
The actual usage of the collected list could be like this:
objcopy -j .guestfsd_ext_cmds -O binary daemon/guestfsd /dev/stdout |
tr '\0' '\n' | sort -u
The resulting output will be used to tell mkinitrd which programs to
copy into the initrd.
Signed-off-by: Olaf Hering <olaf@aepfle.de>
RWMJ:
- Move str_vgchange at request of author.
- Fix snprintf call in daemon/debug.c
The RPC stubs already prefix the command name to error messages.
The daemon doesn't have to do this. As a (small) benefit this also
makes the daemon slightly smaller.
Code in the daemon such as:
if (argv[0] == NULL) {
reply_with_error ("passed an empty list");
return NULL;
}
now results in error messages like this:
><fs> command ""
libguestfs: error: command: passed an empty list
(whereas previously you would have seen ..command: command:..)
The current groups are defined very conservatively using the
following criteria:
(a) Would be impossible to implement on Windows because of
sheer architectural differences (eg: mknod).
(b) Already optional (augeas, inotify).
(c) Not currently optional but not implemented on older RHEL and
Debian releases (ntfs-3g.probe, scrub, zerofree).
The optional groups I've defined according to these criteria are:
. augeas
. inotify
. linuxfsuuid
. linuxmodules
. linuxxattrs
. lvm2
. mknod
. ntfs3g
. scrub
. selinux
. zerofree
(Note that these choices don't prevent us from adding more
optional groups in future. On the other hand to avoid breaking
ABIs we would not wish to change the above groups).
The rest of this large commit is really just implementation:
Each optional function is classified using Optional "group"
flag in the generator.
The daemon has to implement a function
int optgroup_<name>_available (void);
for each optional group. Some of these functions are fixed at
compile time, and some do simple run-time tests.
The do_available implementation in the daemon looks up the correct
function in a table and runs it.
We document the optional groups in the guestfs(3) man page.
Also: I added a NOT_AVAILABLE macro in order to unify all the
existing places where we had a message equivalent to
"function __func__ is not available".
Nearly every file-related function in daemons/*.c is affected:
Remove this pair of statements from each affected do_* function:
- NEED_ROOT (return -1);
- ABS_PATH (dir, return -1);
and change the type of the corresponding parameter to "const char *".
* src/generator.ml: Emit NEED_ROOT just once, even when there are two or
more Pathname args.
