SBUS: Start implementing property access

This patch adds the basis of SBUS getters and setters. A new module,
sssd_dbus_properties.c would contain handlers for the property methods
like Get, Set and GetAll.

Type-safe property access works in a similar fashion like type-safe
method calls - the invoker calls the getter which returns the primitive
type, which is in turn marshalled into variant by the invoker.

This patch does not contain the complete functionality, see later
patches that continue implementing the getters and setters.

Reviewed-by: Stef Walter <stefw@redhat.com>
Reviewed-by: Pavel Březina <pbrezina@redhat.com>

1 files changed, 122 insertions, 0 deletions

diff --git a/src/sbus/sssd_dbus_properties.c b/src/sbus/sssd_dbus_properties.c
new file mode 100644
index 000000000..835b3078b
--- /dev/null
+++ b/src/sbus/sssd_dbus_properties.c
@@ -0,0 +1,122 @@
+/*
+    Authors:
+        Stef Walter <stefw@redhat.com>
+
+    Copyright (C) 2014 Red Hat
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "util/util.h"
+#include "sbus/sssd_dbus.h"
+#include "sbus/sssd_dbus_meta.h"
+#include "sbus/sssd_dbus_private.h"
+
+static int
+dispatch_properties_set(struct sbus_connection *conn,
+                        struct sbus_interface *intf,
+                        DBusMessage *message)
+{
+    const char *signature;
+    const struct sbus_interface_meta *meta;
+    const struct sbus_property_meta *property;
+    const char *interface_name;
+    const char *property_name;
+    const char *type;
+    struct sbus_request *req;
+    sbus_msg_handler_fn handler_fn;
+    DBusMessageIter iter;
+    DBusMessageIter variant;
+
+    req = sbus_new_request(conn, intf, message);
+    if (!req)
+        return ENOMEM;
+
+    meta = intf->vtable->meta;
+
+    signature = dbus_message_get_signature(message);
+    if (strcmp (signature, "ssv") != 0) {
+        return sbus_request_fail_and_finish(req,
+                    sbus_error_new(req,
+                                   DBUS_ERROR_INVALID_ARGS,
+                                   "Invalid argument types passed " \
+                                   "to Set method"));
+    }
+
+    dbus_message_iter_init (message, &iter);
+    dbus_message_iter_get_basic (&iter, &interface_name);
+    dbus_message_iter_next (&iter);
+    dbus_message_iter_get_basic (&iter, &property_name);
+    dbus_message_iter_next (&iter);
+
+    if (strcmp (interface_name, meta->name) != 0) {
+        return sbus_request_fail_and_finish(req,
+                    sbus_error_new(req,
+                                   DBUS_ERROR_UNKNOWN_INTERFACE,
+                                   "No such interface"));
+    }
+
+    property = sbus_meta_find_property (intf->vtable->meta, property_name);
+    if (property == NULL) {
+        return sbus_request_fail_and_finish(req,
+                    sbus_error_new(req,
+                                   DBUS_ERROR_UNKNOWN_PROPERTY,
+                                   "No such property"));
+    }
+
+    if (!(property->flags & SBUS_PROPERTY_WRITABLE)) {
+        return sbus_request_fail_and_finish(req,
+                    sbus_error_new(req,
+                                   DBUS_ERROR_PROPERTY_READ_ONLY,
+                                   "Property is not writable"));
+    }
+
+    dbus_message_iter_recurse(&iter, &variant);
+    type = dbus_message_iter_get_signature (&variant);
+    if (strcmp (property->type, type) != 0) {
+        return sbus_request_fail_and_finish(req,
+                    sbus_error_new(req,
+                                   DBUS_ERROR_INVALID_ARGS,
+                                   "Invalid data type for property"));
+    }
+
+    handler_fn = VTABLE_FUNC(intf->vtable, property->vtable_offset_set);
+    if (!handler_fn) {
+        return sbus_request_fail_and_finish(req,
+                    sbus_error_new(req,
+                                   DBUS_ERROR_NOT_SUPPORTED,
+                                   "Not implemented"));
+    }
+
+    sbus_request_invoke_or_finish(req, handler_fn,
+                                  intf->instance_data,
+                                  property->invoker_set);
+    return EOK;
+}
+
+int sbus_properties_dispatch(struct sbus_request *dbus_req)
+{
+    const char *member;
+
+    member = dbus_message_get_member(dbus_req->message);
+
+    /* Set is handled a lot like a method invocation */
+    if (strcmp(member, "Set") == 0) {
+        return dispatch_properties_set(dbus_req->conn,
+                                       dbus_req->intf,
+                                       dbus_req->message);
+    }
+
+    return ERR_SBUS_NOSUP;
+}