Merge changes from topic "interface_builtins"

* changes:
  init: ServiceList FindInterface
  builtins: interface_{start, stop, restart}
diff --git a/init/builtins.cpp b/init/builtins.cpp
index 8bd92cc..17d34e1 100644
--- a/init/builtins.cpp
+++ b/init/builtins.cpp
@@ -240,6 +240,29 @@
     return Success();
 }
 
+static Result<Success> do_interface_restart(const BuiltinArguments& args) {
+    Service* svc = ServiceList::GetInstance().FindInterface(args[1]);
+    if (!svc) return Error() << "interface " << args[1] << " not found";
+    svc->Restart();
+    return Success();
+}
+
+static Result<Success> do_interface_start(const BuiltinArguments& args) {
+    Service* svc = ServiceList::GetInstance().FindInterface(args[1]);
+    if (!svc) return Error() << "interface " << args[1] << " not found";
+    if (auto result = svc->Start(); !result) {
+        return Error() << "Could not start interface: " << result.error();
+    }
+    return Success();
+}
+
+static Result<Success> do_interface_stop(const BuiltinArguments& args) {
+    Service* svc = ServiceList::GetInstance().FindInterface(args[1]);
+    if (!svc) return Error() << "interface " << args[1] << " not found";
+    svc->Stop();
+    return Success();
+}
+
 // mkdir <path> [mode] [owner] [group]
 static Result<Success> do_mkdir(const BuiltinArguments& args) {
     mode_t mode = 0755;
@@ -1050,6 +1073,9 @@
         {"init_user0",              {0,     0,    {false,  do_init_user0}}},
         {"insmod",                  {1,     kMax, {true,   do_insmod}}},
         {"installkey",              {1,     1,    {false,  do_installkey}}},
+        {"interface_restart",       {1,     1,    {false,  do_interface_restart}}},
+        {"interface_start",         {1,     1,    {false,  do_interface_start}}},
+        {"interface_stop",          {1,     1,    {false,  do_interface_stop}}},
         {"load_persist_props",      {0,     0,    {false,  do_load_persist_props}}},
         {"load_system_props",       {0,     0,    {false,  do_load_system_props}}},
         {"loglevel",                {1,     1,    {false,  do_loglevel}}},
diff --git a/init/init.cpp b/init/init.cpp
index 54bbb4b..645184b 100644
--- a/init/init.cpp
+++ b/init/init.cpp
@@ -297,40 +297,29 @@
 
     const ControlMessageFunction& function = it->second;
 
-    if (function.target == ControlTarget::SERVICE) {
-        Service* svc = ServiceList::GetInstance().FindService(name);
-        if (svc == nullptr) {
-            LOG(ERROR) << "No such service '" << name << "' for ctl." << msg;
-            return;
-        }
-        if (auto result = function.action(svc); !result) {
-            LOG(ERROR) << "Could not ctl." << msg << " for service " << name << ": "
-                       << result.error();
-        }
+    Service* svc = nullptr;
 
+    switch (function.target) {
+        case ControlTarget::SERVICE:
+            svc = ServiceList::GetInstance().FindService(name);
+            break;
+        case ControlTarget::INTERFACE:
+            svc = ServiceList::GetInstance().FindInterface(name);
+            break;
+        default:
+            LOG(ERROR) << "Invalid function target from static map key '" << msg << "': "
+                       << static_cast<std::underlying_type<ControlTarget>::type>(function.target);
+            return;
+    }
+
+    if (svc == nullptr) {
+        LOG(ERROR) << "Could not find '" << name << "' for ctl." << msg;
         return;
     }
 
-    if (function.target == ControlTarget::INTERFACE) {
-        for (const auto& svc : ServiceList::GetInstance()) {
-            if (svc->interfaces().count(name) == 0) {
-                continue;
-            }
-
-            if (auto result = function.action(svc.get()); !result) {
-                LOG(ERROR) << "Could not handle ctl." << msg << " for service " << svc->name()
-                           << " with interface " << name << ": " << result.error();
-            }
-
-            return;
-        }
-
-        LOG(ERROR) << "Could not find service hosting interface " << name;
-        return;
+    if (auto result = function.action(svc); !result) {
+        LOG(ERROR) << "Could not ctl." << msg << " for '" << name << "': " << result.error();
     }
-
-    LOG(ERROR) << "Invalid function target from static map key '" << msg
-               << "': " << static_cast<std::underlying_type<ControlTarget>::type>(function.target);
 }
 
 static Result<Success> wait_for_coldboot_done_action(const BuiltinArguments& args) {
diff --git a/init/service.h b/init/service.h
index cf38f69..9cb35b8 100644
--- a/init/service.h
+++ b/init/service.h
@@ -244,6 +244,16 @@
         return nullptr;
     }
 
+    Service* FindInterface(const std::string& interface_name) {
+        for (const auto& svc : services_) {
+            if (svc->interfaces().count(interface_name) > 0) {
+                return svc.get();
+            }
+        }
+
+        return nullptr;
+    }
+
     void DumpState() const;
 
     auto begin() const { return services_.begin(); }