If either the daemon sends back an errno, or a system call
fails in the library, save the errno in the handle and then
make it available to callers through the guestfs_last_errno
function.
This changes the protocol again so that if the errno is available,
it is converted to a string (like "EIO") and sent back over the
protocol to the library.
In this commit the library just discards the string.
Some older tests used sfdisk to create partitions for the
tests. sfdisk is buggy (more so than parted -- what is it
with partitioning tools?) so replace these tests with
equivalent part-* commands.
We are already using heuristics in the C inspection code to
determine the Windows %SYSTEMROOT% directory. This change
just exposes this information through the API.
When logical volume names appear in places like /etc/fstab
files they can have the form "/dev/mapper/foo-bar". This
function takes such names and makes them canonical.
Note that this operation cannot be performed using the current
API, because 'guestfs_stat' does not work on device names, and
we don't really want to make a 'stat-device' call since that
exposes too much non-useful detail about the appliance.
With this patch you can do this:
><fs> debug ll /dev/mapper
total 8
drwxrwxr-x 2 root root 4096 Oct 25 12:51 .
drwxr-xr-x 16 root root 4096 Oct 25 12:51 ..
crw------- 1 root root 10, 62 Oct 25 12:51 control
lrwxrwxrwx 1 root root 7 Oct 25 12:51 vg_f13x64-lv_root -> ../dm-0
lrwxrwxrwx 1 root root 7 Oct 25 12:51 vg_f13x64-lv_swap -> ../dm-1
><fs> lvm-canonical-lv-name /dev/mapper/vg_f13x64-lv_root
/dev/vg_f13x64/lv_root
><fs> lvm-canonical-lv-name /dev/mapper/vg_f13x64-lv_swap
/dev/vg_f13x64/lv_swap
><fs> lvm-canonical-lv-name /dev/mapper/foo
libguestfs: error: lvm_canonical_lv_name: lvm_canonical_lv_name_stub: /dev/mapper/foo: No such file or directory
><fs> lvm-canonical-lv-name /dev/mapper/control
libguestfs: error: lvm_canonical_lv_name: /dev/mapper/control: not a logical volume
><fs> lvm-canonical-lv-name /dev/vg_f13x64/lv_root
/dev/vg_f13x64/lv_root
The example below shows what the output looks like for a large
random buffer.
$ guestfish -N fs -m /dev/sda1 -x -- \
touch /test : \
pwrite /test "$(dd if=/dev/urandom bs=128k count=1)" 0
[...]
pwrite "/test" "\x7f\xa0/\xb3\x80\xd3\xbc\xc3\xc3.\xb1\xe0\x1b\xafC\x06\xd5;\x0ajJ[o\xc1\xdd\xae\x1f\xce\xb2\x8d\xb3\xd0\x11\xcc$%\xe6<\xc7\xc7\xe7BU*\xc4l%\xaa\xea\xe9\x1an\xda]\xc6I\x0eC\xf9;\xec\x12a\x1f\xeaRH\xb2P\xd6+\xc4\xe6\xa5bW\x99\\x9d\xc8\x9bJ\xef\x99-\x16:h5\xe2\x0f\xa2\xa08\x9bU\x0b$\x138\xcf\xd4j\x9b\x83{%\xac0\xdaa1Xx\xbd`\x8e\xdd\x82\x87\x07\x98\xd2\x9ed\x8bq\xd0\x1f5\x8f\xab\xad4z1\xda\xc4b\xc1\xbc\x0f\xaa\xea\xc1\x15(\xfd1\xc2\x0bF\xe6\x9e\xb0+/g\\xab\xb0b\xde_\xca\xf9\xad\xe1?%\x17\xad\x98\xa4e\xc1\xe0f'\x89\xe9>\xff\xadhYi\xe7\x8c]%\xef\xe0\xa1R\xe5\xd5\x03K\xefI\xdf\xad\xd3\x82\xdb\x0f\xdd\xc3\x8f"\xf1G\xea\xf9r\xdd\xff\x88\x81\xb7\xf2\x0e\x0f\x1d;:\xf2F1\xdb\xb5D\xa1^\x928\xf5\x8e)\xab\xc4\xc3H(\xd0ol\xc6\xe4\xd6\xa3L\x1c\x06\xf4"<truncated, original size 130567 bytes> 0
[...]
This large commit changes the generator so that optional arguments
can be supported for functions.
The model for arguments (known as the "style") is changed from
(ret, args) to (ret, args, optargs) where optargs is a more limited
list of arguments.
One function has been added which takes optional arguments, it is
"add-drive-opts", modelled as:
(RErr, [String "filename"], #required
[Bool "readonly"; String "format"; String "iface"]) #optional
Note that this function is processed in the library (does not go over
the RPC protocol to the daemon). This has allowed us to simplify
the current implementation by omitting changes related to RPC or the
daemon, although we plan to add these at some point in the future.
From C this function can be called in 3 different ways as in these
examples:
guestfs_add_drive_opts (g, filename,
GUESTFS_ADD_DRIVE_OPTS_READONLY, 1,
GUESTFS_ADD_DRIVE_OPTS_FORMAT, "raw",
-1);
(the argument(s) between 'filename' and '-1' are the optional ones).
guestfs_add_drive_opts_va (g, filename, args);
where 'args' is a va_list. This works like the first version.
struct guestfs_add_drive_opts_argv optargs = {
.bitmask = GUESTFS_ADD_DRIVE_OPTS_READONLY_BITMASK,
.readonly = 1,
}
guestfs_add_drive_opts_argv (g, filename, &optargs);
This last form lets you construct lists of optional arguments, and
is used by guestfish and the language bindings.
In guestfish optional arguments are used like this:
add-drive-opts filename readonly:true
In OCaml these are mapped naturally to OCaml optional arguments, eg:
g#add_drive_opts ~readonly:true filename;
In Perl these are mapped to extra arguments, eg:
$g->add_drive_opts ($filename, readonly => 1);
In Python these are mapped to optional arguments, eg:
g.add_drive_opts ("file", readonly = 1, format = "qcow2")
In Ruby these are mapped to a final hash argument, eg:
g.add_drive_opts("file", {})
g.add_drive_opts("file", :readonly => 1)
g.add_drive_opts("file", :readonly => 1, :iface => "virtio")
In PHP these are mapped to extra parameters. This is not quite
accurate since you cannot omit arbitrary optional parameters, but
there's not much than can be done within the limitations of PHP
as a language.
Unimplemented in: Haskell, C#, Java.
In original style:
let () =
let filename = Sys.argv.(1) in
let g = Guestfs.create () in
Guestfs.add_drive_ro g filename;
Guestfs.launch g;
let roots = Guestfs.inspect_os g in
print_endline (Guestfs.inspect_get_product_name g roots.(0))
The same code in the new OO style:
let () =
let filename = Sys.argv.(1) in
let g = new Guestfs.guestfs in
g#add_drive_ro filename;
g#launch ();
let roots = g#inspect_os () in
print_endline (g#inspect_get_product_name roots.(0))
Be more consistent in allowing the user to override use of the
temporary directory by specifying $TMPDIR. Also prefer P_tmpdir
macro (defined in <stdio.h>) if that is defined, rather than
hard-coding "/tmp" for the fallback location.
The guestfish-only commands such as 'alloc' and 'edit' are
now generated from one place in the generator instead of being
spread around ad-hoc in the C code.
This API is a simpler replacement for the guestfish commands
list-devices / list-partitions / lvs, in the case where you are
just examining a guest by hand to see what it contains.
Typical usage and output in guestfish is like this:
$ guestfish --ro -a /dev/vg_trick/F13x64
><fs> run
><fs> list-filesystems
/dev/vda1: ext4
/dev/vg_f13x64/lv_root: ext4
/dev/vg_f13x64/lv_swap: swap
It can also be used to replace programs that try to mount
devices to determine if they are mountable filesystems.
This is for testing functions that return a device or partition
name, so that we can compare the return value with the canonical
device name (eg. "/dev/vda1" == "/dev/sda1").
Because this used to be compiled into the C test, it changed
every time the ISO was rebuilt (which because of Makefile deps
was every run).
Now it is calculated at runtime so the C test file doesn't keep
changing.
'src/generator.ml' is no more. Instead the generator is logically
split up over many different source files.
Read generator/README for help and tips.
We compile the generator down to bytecode, not native code. This
means it will run more slowly, but is done for maximum portability.
