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, 60 insertions, 12 deletions

diff --git a/src/sbus/sbus_codegen b/src/sbus/sbus_codegen
index 6c4b8ec9a..96248a628 100755
--- a/src/sbus/sbus_codegen
+++ b/src/sbus/sbus_codegen
@@ -114,10 +114,9 @@ BASIC_TYPES = {
  'o': ( "DBUS_TYPE_OBJECT_PATH", "const char *", "const char *" ),
 }
 
-class Arg(Base):
-    def __init__(self, method, name, type):
+class Typed(Base):
+    def __init__(self, name, type):
         Base.__init__(self, name)
-        self.method = method
         self.type = type
         self.is_basic = False
         self.is_array = False
@@ -135,6 +134,11 @@ class Arg(Base):
             else:
                 self.is_basic = True
 
+class Arg(Typed):
+    def __init__(self, method, name, type):
+        Typed.__init__(self, name, type)
+        self.method = method
+
 class Method(Base):
     def __init__(self, iface, name):
         Base.__init__(self, name)
@@ -166,11 +170,10 @@ class Signal(Base):
     def fq_c_name(self):
         return "%s_%s" % (self.iface.c_name(), self.c_name())
 
-class Property(Base):
-    def __init__(self, iface, name, signature, access):
-        Base.__init__(self, name)
+class Property(Typed):
+    def __init__(self, iface, name, type, access):
+        Typed.__init__(self, name, type)
         self.iface = iface
-        self.signature = signature
         self.readable = False
         self.writable = False
         if access == 'readwrite':
@@ -234,7 +237,7 @@ def method_function_pointer(meth, name, with_names=False):
              with_names and "data" or "",
              method_arg_types(meth.in_args, with_names))
 
-def forward_invoker(signature, args):
+def forward_method_invoker(signature, args):
     out("")
     out("/* invokes a handler with a '%s' DBus signature */", signature)
     out("static int invoke_%s_method(struct sbus_request *dbus_req, void *function_ptr);", signature)
@@ -275,6 +278,53 @@ def source_method_invoker(signature, args):
     out(");")
     out("}")
 
+def source_getter_invoker(prop):
+    out("")
+    out("/* invokes a getter with a '%s' DBus type */", type)
+    out("static int invoke_%s_getter(struct sbus_request *request, struct sbus_interface *intf, void *function_ptr)", prop.type)
+    out("{")
+    out("    DBusError error = DBUS_ERROR_INIT;")
+    out("    int ret;")
+    for i in range(0, len(args)):
+        arg = args[i]
+        if arg.is_array:
+            out("    %s *arg_%d;", arg.dbus_type, i)
+            out("    int len_%d;", i)
+        else:
+            out("    %s arg_%d;", arg.dbus_type, i)
+    out("    int (*handler)(struct sbus_request *, void *%s) = function_ptr;", method_arg_types(args))
+    out("")
+    out("    if (!dbus_message_get_args(request->message, &error,")
+    for i in range(0, len(args)):
+        arg = args[i]
+        if arg.is_array:
+            out("                               DBUS_TYPE_ARRAY, %s, &arg_%d, &len_%d,",
+                arg.dbus_constant, i, i)
+        else:
+            out("                               %s, &arg_%d,", arg.dbus_constant, i)
+    out("                               DBUS_TYPE_INVALID)) {")
+    out("         ret = sbus_request_fail_and_finish(request, error.name, error.message);")
+    out("         dbus_error_free(&error);")
+    out("         return ret;")
+    out("    }")
+    out("")
+
+    out("    ret = (handler)(request, intf", new_line=False)
+    for i in range(0, len(args)):
+        arg = args[i]
+        out(",\n                    arg_%d", i, new_line=False)
+        if arg.is_array:
+            out(",\n                    len_%d", i, new_line=False)
+    out(");")
+    out("")
+
+    for i in range(0, len(args)):
+        arg = args[i]
+        if arg.type in ["as", "ao"]:
+            out("    dbus_free_string_array((char **)arg_%d);", i)
+    out("    return ret;")
+    out("}")
+
 def forward_method_invokers(ifaces):
     invokers = { }
     for iface in ifaces:
@@ -284,7 +334,7 @@ def forward_method_invokers(ifaces):
             signature = meth.in_signature()
             if signature in invokers:
                 continue
-            forward_invoker(signature, meth.in_args)
+            forward_method_invoker(signature, meth.in_args)
             invokers[signature] = meth
     return invokers
 
@@ -392,7 +442,7 @@ def source_properties(iface, properties):
     for prop in properties:
         out("    {")
         out("        \"%s\", /* name */", prop.name)
-        out("        \"%s\", /* signature */", prop.signature)
+        out("        \"%s\", /* type */", prop.type)
         if prop.readable and prop.writable:
             out("        SBUS_PROPERTY_READABLE | SBUS_PROPERTY_WRITABLE,")
         elif prop.readable:
@@ -480,8 +530,6 @@ def header_vtable(iface, methods):
     for meth in iface.methods:
         out("    %s;", method_function_pointer(meth, meth.c_name(), with_names=True))
 
-    # TODO: Property getters and setters will go here
-
     out("};")
 
 def header_constants(iface):