On Wed, 23 Jun 2010 17:21:12 +0200
Markus Armbruster <arm...@redhat.com> wrote:
> Luiz Capitulino <lcapitul...@redhat.com> writes:
>
> > This commit introduces the second (and last) part of QMP's new
> > argument checker.
> >
> > The job is done by check_client_args_type(), it iterates over
> > the client's argument qdict and for for each argument it checks
> > if it exists and if its type is valid.
> >
> > It's important to observe the following changes from the existing
> > argument checker:
> >
> > - If the handler accepts an O-type argument, unknown arguments
> > are passed down to it. It's up to O-type handlers to validate
> > their arguments
> >
> > - Boolean types (eg. 'b' and '-') don't accept integers anymore,
> > only json-bool
> >
> > - Argument types '/' and '.' are currently unsupported under QMP,
> > thus they're not handled
> >
> > Signed-off-by: Luiz Capitulino <lcapitul...@redhat.com>
> > ---
> > monitor.c | 100
> > ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
> > 1 files changed, 99 insertions(+), 1 deletions(-)
> >
> > diff --git a/monitor.c b/monitor.c
> > index b4fe5ba..8d074c2 100644
> > --- a/monitor.c
> > +++ b/monitor.c
> > @@ -4139,6 +4139,101 @@ static int invalid_qmp_mode(const Monitor *mon,
> > const char *cmd_name)
> > }
> >
> > /*
> > + * Argument validation rules:
> > + *
> > + * 1. The argument must exist in cmd_args qdict
> > + * 2. The argument type must be the expected one
> > + *
> > + * Special case: If the argument doesn't exist in cmd_args and
> > + * the QMP_CHECKER_OTYPE flag is set, then the
> > + * argument is considered an O-type one and the
> > + * checking is skipped for it.
> > + */
> > +static int check_client_args_type(const QDict *client_args,
> > + const QDict *cmd_args, int flags)
> > +{
> > + const QDictEntry *ent;
> > +
> > + for (ent = qdict_first(client_args); ent;ent =
> > qdict_next(client_args,ent)){
> > + QObject *obj;
> > + QString *arg_type;
> > + const QObject *client_arg = qdict_entry_value(ent);
> > + const char *client_arg_name = qdict_entry_key(ent);
> > +
> > + obj = qdict_get(cmd_args, client_arg_name);
> > + if (!obj) {
> > + if (flags & QMP_CHECKER_OTYPE) {
> > + /*
> > + * This handler accepts O-type arguments, it's up to it to
> > + * check for unknowns and validate its type.
> > + */
> > + continue;
> > + }
> > + /* client arg doesn't exist */
> > + qerror_report(QERR_INVALID_PARAMETER, client_arg_name);
> > + return -1;
> > + }
> > +
> > + arg_type = qobject_to_qstring(obj);
> > + assert(arg_type != NULL);
> > +
> > + /* check if argument's type is correct */
> > + switch (qstring_get_str(arg_type)[0]) {
> > + case 'F':
> > + case 'B':
> > + case 's':
> > + if (qobject_type(client_arg) != QTYPE_QSTRING) {
> > + qerror_report(QERR_INVALID_PARAMETER_TYPE, client_arg_name,
> > + "string");
> > + return -1;
> > + }
> > + break;
> > + case 'i':
> > + case 'l':
> > + case 'M':
> > + if (qobject_type(client_arg) != QTYPE_QINT) {
> > + qerror_report(QERR_INVALID_PARAMETER_TYPE, client_arg_name,
> > + "int");
> > + return -1;
> > + }
> > + break;
> > + case 'f':
> > + case 'T':
> > + if (qobject_type(client_arg) != QTYPE_QINT &&
> > + qobject_type(client_arg) != QTYPE_QFLOAT) {
> > + qerror_report(QERR_INVALID_PARAMETER_TYPE, client_arg_name,
> > + "number");
> > + return -1;
> > + }
> > + break;
> > + case 'b':
> > + case '-':
> > + if (qobject_type(client_arg) != QTYPE_QBOOL) {
> > + qerror_report(QERR_INVALID_PARAMETER_TYPE, client_arg_name,
> > + "bool");
> > + return -1;
> > + }
> > + break;
> > + case 'O':
> > + /* XXX: this argument has the same name of the O-type defined
> > in
> > + in qemu-monitor.hx. This is not allowed, right? */
>
>
> No, it's actually fine.
>
> Consider device_add. Its args_type is "device:O". Nevertheless, it's
> pefectly okay for a qdev to have a property named "device".
>
> > + qerror_report(QERR_INVALID_PARAMETER, client_arg_name);
> > + return -1;
>
> Instead:
>
> assert(flags & QMP_CHECKER_OTYPE);
> continue;
Ok, but isn't it better to choose a name which is unlikely to be a property?
Maybe something like "device_add_opts_list:O"?
> Not sure I like the name QMP_CHECKER_OTYPE. The way it's used, it means
> "in addition to checking declared arguments, accept undeclared arguments
> without checking them (somebody else will check)". 'O-type' is merely
> something that triggers that flag. Happens to be the only way right
> now.
>
> QMP_CHECKER_ACCEPT_MORE_ARGS?
Or QMP_CHECKER_ACCEPT_UNKNOWNS, but it's too long..
>
> > + case '/':
> > + case '.':
> > + /*
> > + * These types are not supported by QMP and thus are not
> > + * handled here. Fall through.
> > + */
> > + default:
> > + abort();
> > + }
> > + }
> > +
> > + return 0;
> > +}
> > +
> > +/*
> > * - Check if the client has passed all mandatory args
> > * - Set special flags for argument validation
> > */
> > @@ -4215,6 +4310,9 @@ out:
> > * Client argument checking rules:
> > *
> > * 1. Client must provide all mandatory arguments
> > + * 2. Each argument provided by the client must be expected
> > + * 3. Each argument provided by the client must have the type expected
> > + * by the command
> > */
> > static int qmp_check_client_args(const mon_cmd_t *cmd, QDict *client_args)
> > {
> > @@ -4229,7 +4327,7 @@ static int qmp_check_client_args(const mon_cmd_t
> > *cmd, QDict *client_args)
> > goto out;
> > }
> >
> > - /* TODO: Check client args type */
> > + err = check_client_args_type(client_args, cmd_args, flags);
> >
> > out:
> > QDECREF(cmd_args);
>
