In qmp-marshal.c the dealloc visitor calls use the same errp
pointer of the input visitor calls. This means that if any of
the input visitor calls fails, then the dealloc visitor will
return early, before freeing the object's memory.
Here's an example, consider this code:
int qmp_marshal_input_block_passwd(Monitor *mon, const QDict *qdict, QObject **ret)
{
[...]
char * device = NULL;
char * password = NULL;
mi = qmp_input_visitor_new_strict(QOBJECT(args));
v = qmp_input_get_visitor(mi);
visit_type_str(v, &device, "device", errp);
visit_type_str(v, &password, "password", errp);
qmp_input_visitor_cleanup(mi);
if (error_is_set(errp)) {
goto out;
}
qmp_block_passwd(device, password, errp);
out:
md = qapi_dealloc_visitor_new();
v = qapi_dealloc_get_visitor(md);
visit_type_str(v, &device, "device", errp);
visit_type_str(v, &password, "password", errp);
qapi_dealloc_visitor_cleanup(md);
[...]
return 0;
}
Consider errp != NULL when the out label is reached, we're going
to leak device and password.
This patch fixes this by always passing errp=NULL for dealloc
visitors, meaning that we always try to free them regardless of
any previous failure. The above example would then be:
out:
md = qapi_dealloc_visitor_new();
v = qapi_dealloc_get_visitor(md);
visit_type_str(v, &device, "device", NULL);
visit_type_str(v, &password, "password", NULL);
qapi_dealloc_visitor_cleanup(md);
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
The file is only including error.h and qerror.h. Prefer explicit
inclusion of whatever files are needed.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
qmp-commands.h declares several functions that have arguments of
type QDict. However, qdict.h is not included. This will cause a
build breakage when a file includes qmp-commands.h but doesn't
include qdict.h.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Options allow for changes in commands behavior. This commit introduces
the QCO_NO_SUCCESS_RESP option, which causes a command to not emit a
success response.
This is needed by commands such as qemu-ga's guest-shutdown, which
may not be able to complete before the VM vanishes. In this case, it's
useful and simpler not to bother sending a success response.
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
The fixes to qapi code generation had multiple bugs:
- the Null class used to drop output was missing some methods
- in some scripts it was never instantiated, leading to a None return,
which is missing even more methods
- the --source and --header options were swapped
Luckily, all those bugs were hidden by a makefile bug which caused the
old behaviour (with the race) to be invoked.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Make's multiple output syntax
x.c x.h: x.template
gen < x.template
actually invokes the command once for x.c and once for x.h (with differing $@
in each invocation). During a parallel build, the two commands may be invoked
in parallel; this opens up a race, where the second invocation trashes a file
supposedly produced during the first, and now in use by a dependent command.
The various qapi code generators are susceptible to this; fix by making them
generate just one file per invocation.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Today we generate something like this:
int qmp_marshal_input_query_foo(...)
...
retval = qmp_query_foo(errp);
qmp_marshal_output_query_foo(retval, ret, errp);
...
However, if qmp_query_foo() fails 'retval' will probably be NULL,
which can cause a segfault as not all visitors check if 'retval'
is valid.
This commit fixes that by changing the code generator to only
call the output marshal if qmp_query_foo() succeeds, like this:
retval = qmp_query_foo(errp);
if (!error_is_set(errp)) {
qmp_marshal_output_query_foo(retval, ret, errp);
}
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
To get the ball rolling merging QAPI, this patch introduces a "middle mode" to
the code generator. In middle mode, the code generator generates marshalling
functions that are compatible with the current QMP server. We absolutely need
to replace the current QMP server in order to support proper asynchronous
commands but using a middle mode provides a middle-ground that lets us start
converting commands in tree.
Note that all of the commands have been converted already in my glib branch.
Middle mode only exists until we finish merging them from my branch into the
main tree.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Fixes a build issue on RHEL5, and potentially other distros, where gcc
will generate an error due to us not writing a trailing "\n" when
generating *qmp-commands.h
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This is the code generator for qapi command marshaling/dispatch.
Currently only generators for synchronous qapi/qmp functions are
supported. This script generates the following files:
$(prefix)qmp-marshal.c: command marshal/dispatch functions for each
QMP command defined in the schema. Functions
generated by qapi-visit.py are used to
convert qobjects recieved from the wire into
function parameters, and uses the same
visiter functions to convert native C return
values to qobjects from transmission back
over the wire.
$(prefix)qmp-commands.h: Function prototypes for the QMP commands
specified in the schema.
$(prefix) is used in the same manner as with qapi-types.py
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Luiz Capitulino <lcapitulino@gmail.com>
