Commit Graph

8 Commits

Author SHA1 Message Date
Michael Roth
e55eb806db qga: fix w32 breakage due to missing osdep.h includes
requester.h relied on qemu/compiler.h definitions to
handle GCC_FMT_ATTR() stub, but this include was removed as part
of scripted clean-ups via 30456d5:

  all: Clean up includes

under the assumption that all C files would have included it via
qemu/osdep.h at that point. requester.cpp was likely missed
due to C++ files requiring manual/special handling as well as
VSS build options needing to be enabled to trigger build failures.

Fix this by including qemu/osdep.h. That in turn pulls in a
macro from qapi/error.h that conflicts with a struct field name
in requester.h, so fix that as well by renaming the field.

While we're at it, fix up provider.cpp/install.cpp to include
osdep.h as well.

Cc: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-02-25 10:54:32 -06:00
Peter Maydell
4459bf3866 qga: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1454089805-5470-9-git-send-email-peter.maydell@linaro.org
2016-02-04 17:41:30 +00:00
Markus Armbruster
1e9b65bb1b error: On abort, report where the error was created
This is particularly useful when we abort in error_propagate(),
because there the stack backtrace doesn't lead to where the error was
created.  Looks like this:

    Unexpected error in parse_block_error_action() at .../qemu/blockdev.c:322:
    qemu-system-x86_64: -drive if=none,werror=foo: 'foo' invalid write error action
    Aborted (core dumped)

Note: to get this example output, I monkey-patched drive_new() to pass
&error_abort to blockdev_init().

To keep the error handling boiler plate from growing even more, all
error_setFOO() become macros expanding into error_setFOO_internal()
with additional __FILE__, __LINE__, __func__ arguments.  Not exactly
pretty, but it works.

The macro trickery breaks down when you take the address of an
error_setFOO().  Fortunately, we do that in just one place: qemu-ga's
Windows VSS provider and requester DLL wants to call
error_setg_win32() through a function pointer "to avoid linking glib
to the DLL".  Use error_setg_win32_internal() there.  The use of the
function pointer is already wrapped in a macro, so the churn isn't
bad.

Code size increases by some 35KiB for me (0.7%).  Tolerable.  Could be
less if we passed relative rather than absolute source file names to
the compiler, or forwent reporting __func__.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
2015-09-10 13:48:06 +02:00
Markus Armbruster
08e6464035 qga/vss-win32: Document the DLL requires non-null errp
requester.cpp uses this pattern to receive an error and pass it on to
the caller (err_is_set() macro peeled off for clarity):

    ... code that may set errset->errp ...
    if (errset->errp && *errset->errp) {
        ... handle error ...
    }

This breaks when errset->errp is null.  As far as I can tell, it
currently isn't, so this is merely fragile, not actually broken.

The robust way to do this is to receive the error in a local variable,
then propagate it up, like this:

    Error *err = NULL;

    ... code that may set err ...
    if (err)
        ... handle error ...
        error_propagate(errset->errp, err);
    }

See also commit 5e54769, 0f230bf, a903f40.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-09-10 13:48:06 +02:00
Markus Armbruster
e7cf59e847 qga: Clean up unnecessarily dirty casts
qga_vss_fsfreeze() casts error_set_win32() from

    void (*)(Error **, int, ErrorClass, const char *, ...)

to

    void (*)(void **, int, int, const char *, ...)

The result is later called.  Since the two types are not compatible,
the call is undefined behavior.  It works in practice anyway.

However, there's no real need for trickery here.  Clean it up as
follows:

* Declare struct Error, and fix the first parameter.

* Switch to error_setg_win32().  This gets rid of the troublesome
  ErrorClass parameter.  Requires converting error_setg_win32() from
  macro to function, but that's trivially easy, because this is the
  only user of error_set_win32().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2015-09-10 13:48:06 +02:00
Markus Armbruster
77dbc81b0f qga: Consistently name Error ** objects errp, and not err
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2014-05-09 09:11:26 -04:00
Tomoki Sekiyama
f311f2c20a qemu-ga: Install Windows VSS provider on `qemu-ga -s install'
Register QGA VSS provider library into Windows when qemu-ga is installed as
Windows service ('-s install' option). It is deregistered when the service
is uninstalled ('-s uninstall' option).

Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama@hds.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
2013-09-09 14:17:57 -05:00
Tomoki Sekiyama
64c0031740 qemu-ga: Call Windows VSS requester in fsfreeze command handler
Support guest-fsfreeze-freeze and guest-fsfreeze-thaw commands for Windows
guests. When fsfreeze command is issued, it calls the VSS requester to
freeze filesystems and applications. On thaw command, it again tells the VSS
requester to thaw them.

This also adds calling of initialize functions for the VSS requester.

Signed-off-by: Tomoki Sekiyama <tomoki.sekiyama@hds.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
2013-09-09 14:17:57 -05:00