Implement call_sync

Signed-off-by: Rahix <rahix@rahix.de>

bc.lua

@@ -250,6 +250,31 @@ function BaseControl:call(verb, ...)
     error("unknown verb")
   end
 end
+
+function BaseControl:call_sync(verb, ...)
+  if self.local_verbs[verb] ~= nil then
+    return self.local_verbs[verb](...)
+  elseif self.remote_verbs[verb] ~= nil then
+    self.network:send(self.remote_verbs[verb], {
+      ty=Message.VerbRequest,
+      verb=verb,
+      param={...},
+      sync=true,
+    })
+    local answer, err = self.network:pull(function(remote, msg)
+      if remote ~= self.remote_nouns[noun] then return false end
+      if msg.ty ~= Message.NounResponse then return false end
+      if msg.noun ~= noun then return false end
+    end, timeout)
+    if answer ~= nil then
+      return table.unpack(answer.ret)
+    else
+      return nil, err
+    end
+  else
+    error("unknown verb")
+  end
+end
 -- }}}
 
 -- Network Handler {{{
@@ -280,8 +305,17 @@ function BaseControl:_network_handler(remote, msg)
     -- Handled via pull
   elseif msg.ty == Message.VerbRequest then
     if self.local_verbs[msg.verb] ~= nil then
-      self.local_verbs[msg.verb](table.unpack(msg.param))
+      local ret = table.pack(self.local_verbs[msg.verb](table.unpack(msg.param)))
+      if msg.sync then
+        self.network:send(remote, {
+          ty=Message.VerbResponse,
+          verb=msg.verb,
+          ret=ret,
+        })
+      end
     end
+  elseif msg.ty == Message.VerbResponse then
+    -- Handled via pull
   else
     error("TODO: MessageType Unknown")
   end

tests/network.lua

@@ -75,3 +75,29 @@ function test_call_network()
   assert_equal(4321, tmp, "call incomplete")
   assert_equal(1, n, "call not correct")
 end
+
+function test_call_sync()
+  local bc1 = BaseControl:new()
+  local n = 0
+  bc1:register("sync1", function(p1, p2)
+    assert_equal(p2, 12)
+    n = n + 1
+    return p1 + 10, "hello"
+  end)
+  bc1:finalize()
+
+  -- Test locally
+  assert_nil(bc1:call("sync1", 20, 12), "call not nil")
+  local ret, val = bc1:call_sync("sync1", 30, 12)
+  assert_equal(40, ret, "local sync not correct")
+  assert_equal("hello", val, "local sync not multiple")
+  assert_equal(2, n, "wrong invokation number")
+
+  -- Test remote
+  local bc2 = BaseControl:new()
+  assert_nil(bc2:call("sync1", 20, 12), "call not nil")
+  local ret, val = bc2:call_sync("sync1", 30, 12)
+  assert_equal(40, ret, "local sync not correct")
+  assert_equal("hello", val, "local sync not multiple")
+  assert_equal(4, n, "wrong invokation number")
+end