C++ migration: still more threading code cleanup. 'sudo' global moved in the Universe

9 files changed, 67 insertions, 68 deletions

diff --git a/src/deep.h b/src/deep.h
index 1799cf0..c09af23 100644
--- a/src/deep.h
+++ b/src/deep.h
@@ -19,7 +19,7 @@ extern "C" {
 #include <atomic>
 
 // forwards
-struct Universe;
+class Universe;
 
 enum class LookupMode
 {
diff --git a/src/keeper.h b/src/keeper.h
index 931c1d5..ba5a57b 100644
--- a/src/keeper.h
+++ b/src/keeper.h
@@ -15,7 +15,7 @@ extern "C" {
 
 // forwards
 enum class LookupMode;
-struct Universe;
+class Universe;
 
 struct Keeper
 {
diff --git a/src/lanes.cpp b/src/lanes.cpp
index f5d5130..28f95f6 100644
--- a/src/lanes.cpp
+++ b/src/lanes.cpp
@@ -136,7 +136,7 @@ void Lane::startThread(int priority_)
     m_thread = std::jthread([this]() { lane_main(this); });
     if (priority_ != THREAD_PRIO_DEFAULT)
     {
-        JTHREAD_SET_PRIORITY(m_thread, priority_);
+        JTHREAD_SET_PRIORITY(m_thread, priority_, U->m_sudo);
     }
 }
 
@@ -784,7 +784,7 @@ LUAG_FUNC(get_debug_threadname)
 
 LUAG_FUNC(set_thread_priority)
 {
-    int const prio{ (int) luaL_checkinteger(L, 1) };
+    lua_Integer const prio{ luaL_checkinteger(L, 1) };
     // public Lanes API accepts a generic range -3/+3
     // that will be remapped into the platform-specific scheduler priority scheme
     // On some platforms, -3 is equivalent to -2 and +3 to +2
@@ -792,7 +792,7 @@ LUAG_FUNC(set_thread_priority)
     {
         return luaL_error(L, "priority out of range: %d..+%d (%d)", THREAD_PRIO_MIN, THREAD_PRIO_MAX, prio);
     }
-    THREAD_SET_PRIORITY(prio);
+    THREAD_SET_PRIORITY(static_cast<int>(prio), universe_get(L)->m_sudo);
     return 0;
 }
 
@@ -1746,32 +1746,6 @@ static void init_once_LOCKED( void)
 #if (defined PLATFORM_OSX) && (defined _UTILBINDTHREADTOCPU)
     chudInitialize();
 #endif
-
-    //---
-    // Linux needs SCHED_RR to change thread priorities, and that is only
-    // allowed for sudo'ers. SCHED_OTHER (default) has no priorities.
-    // SCHED_OTHER threads are always lower priority than SCHED_RR.
-    //
-    // ^-- those apply to 2.6 kernel.  IF **wishful thinking** these 
-    //     constraints will change in the future, non-sudo priorities can 
-    //     be enabled also for Linux.
-    //
-#ifdef PLATFORM_LINUX
-    sudo = (geteuid() == 0); // we are root?
-
-    // If lower priorities (-2..-1) are wanted, we need to lift the main
-    // thread to SCHED_RR and 50 (medium) level. Otherwise, we're always below
-    // the launched threads (even -2).
-    //
-#ifdef LINUX_SCHED_RR
-    if (sudo)
-    {
-        struct sched_param sp;
-        sp.sched_priority = _PRIO_0;
-        PT_CALL(pthread_setschedparam(pthread_self(), SCHED_RR, &sp));
-    }
-#endif // LINUX_SCHED_RR
-#endif // PLATFORM_LINUX
 }
 
 // #################################################################################################
diff --git a/src/state.h b/src/state.h
index 0e35e89..0e069da 100644
--- a/src/state.h
+++ b/src/state.h
@@ -3,7 +3,7 @@
 #include "macros_and_utils.h"
 
 // forwards
-struct Universe;
+class Universe;
 
 void serialize_require(DEBUGSPEW_PARAM_COMMA(Universe* U) lua_State* L);
 
diff --git a/src/threading.cpp b/src/threading.cpp
index aab2fa7..4d210d6 100644
--- a/src/threading.cpp
+++ b/src/threading.cpp
@@ -65,12 +65,6 @@ THE SOFTWARE.
 # include <unistd.h>
 #endif
 
-/* Linux needs to check, whether it's been run as root
-*/
-#ifdef PLATFORM_LINUX
-  volatile bool sudo;
-#endif
-
 #ifdef PLATFORM_OSX
 # include "threading_osx.h"
 #endif
@@ -134,10 +128,10 @@ static int const gs_prio_remap[] =
 
 // ###############################################################################################
 
-void THREAD_SET_PRIORITY(int prio)
+void THREAD_SET_PRIORITY(int prio_, [[maybe_unused]] bool sudo_)
 {
     // prio range [-3,+3] was checked by the caller
-    if (!SetThreadPriority(GetCurrentThread(), gs_prio_remap[prio + 3]))
+    if (!SetThreadPriority(GetCurrentThread(), gs_prio_remap[prio_ + 3]))
     {
         FAIL("THREAD_SET_PRIORITY", GetLastError());
     }
@@ -145,7 +139,7 @@ void THREAD_SET_PRIORITY(int prio)
 
 // ###############################################################################################
 
-void JTHREAD_SET_PRIORITY(std::jthread& thread_, int prio_)
+void JTHREAD_SET_PRIORITY(std::jthread& thread_, int prio_, [[maybe_unused]] bool sudo_)
 {
     // prio range [-3,+3] was checked by the caller
     if (!SetThreadPriority(thread_.native_handle(), gs_prio_remap[prio_ + 3]))
@@ -368,25 +362,25 @@ static int select_prio(int prio /* -3..+3 */)
     return gs_prio_remap[prio + 3];
 }
 
-void THREAD_SET_PRIORITY(int prio)
+void THREAD_SET_PRIORITY(int prio_, [[maybe_unused]] bool sudo_)
 {
 #ifdef PLATFORM_LINUX
-    if (!sudo) // only root-privileged process can change priorities
+    if (!sudo_) // only root-privileged process can change priorities
         return;
 #endif // PLATFORM_LINUX
 
     struct sched_param sp;
     // prio range [-3,+3] was checked by the caller
-    sp.sched_priority = gs_prio_remap[prio + 3];
+    sp.sched_priority = gs_prio_remap[prio_ + 3];
     PT_CALL(pthread_setschedparam(pthread_self(), _PRIO_MODE, &sp));
 }
 
 // #################################################################################################
 
-void JTHREAD_SET_PRIORITY(std::jthread& thread_, int prio_)
+void JTHREAD_SET_PRIORITY(std::jthread& thread_, int prio_, [[maybe_unused]] bool sudo_)
 {
 #ifdef PLATFORM_LINUX
-    if (!sudo) // only root-privileged process can change priorities
+    if (!sudo_) // only root-privileged process can change priorities
         return;
 #endif // PLATFORM_LINUX
 
diff --git a/src/threading.h b/src/threading.h
index c443c82..f38b2de 100644
--- a/src/threading.h
+++ b/src/threading.h
@@ -58,33 +58,19 @@ static constexpr int THREAD_PRIO_MAX{ +3 };
 #endif // PLATFORM_WIN32
 #include <pthread.h>
 
-// Yield is non-portable:
-//
-//    OS X 10.4.8/9 has pthread_yield_np()
-//    Linux 2.4   has pthread_yield() if _GNU_SOURCE is #defined
-//    FreeBSD 6.2 has pthread_yield()
-//    ...
-//
-
-#if defined(PLATFORM_LINUX)
-extern volatile bool sudo;
-#   ifdef LINUX_SCHED_RR
-#       define THREAD_PRIO_MIN (sudo ? -3 : 0)
-#   else
+#if defined(PLATFORM_LINUX) && !defined(LINUX_SCHED_RR)
 static constexpr int THREAD_PRIO_MIN{ 0 };
-#endif
-#       define THREAD_PRIO_MAX (sudo ? +3 : 0)
 #else
 static constexpr int THREAD_PRIO_MIN{ -3 };
-static constexpr int THREAD_PRIO_MAX{ +3 };
 #endif
+static constexpr int THREAD_PRIO_MAX{ +3 };
 
-#endif // THREADAPI == THREADAPI_WINDOWS
+#endif // THREADAPI == THREADAPI_PTHREAD
 // ##################################################################################################
 // ##################################################################################################
 
 void THREAD_SETNAME(char const* _name);
-void THREAD_SET_PRIORITY(int prio);
+void THREAD_SET_PRIORITY(int prio_, bool sudo_);
 void THREAD_SET_AFFINITY(unsigned int aff);
 
-void JTHREAD_SET_PRIORITY(std::jthread& thread_, int prio_);
+void JTHREAD_SET_PRIORITY(std::jthread& thread_, int prio_, bool sudo_);
diff --git a/src/tools.h b/src/tools.h
index c1a8534..7d9aaab 100644
--- a/src/tools.h
+++ b/src/tools.h
@@ -6,7 +6,7 @@
 #include "macros_and_utils.h"
 
 // forwards
-struct Universe;
+class Universe;
 
 // ################################################################################################
 
diff --git a/src/universe.cpp b/src/universe.cpp
index 66da147..290e547 100644
--- a/src/universe.cpp
+++ b/src/universe.cpp
@@ -43,6 +43,35 @@ static constexpr UniqueKey UNIVERSE_LIGHT_REGKEY{ 0x3663C07C742CEB81ull };
 
 // ################################################################################################
 
+Universe::Universe()
+{
+    //---
+    // Linux needs SCHED_RR to change thread priorities, and that is only
+    // allowed for sudo'ers. SCHED_OTHER (default) has no priorities.
+    // SCHED_OTHER threads are always lower priority than SCHED_RR.
+    //
+    // ^-- those apply to 2.6 kernel.  IF **wishful thinking** these
+    //     constraints will change in the future, non-sudo priorities can
+    //     be enabled also for Linux.
+    //
+#ifdef PLATFORM_LINUX
+    // If lower priorities (-2..-1) are wanted, we need to lift the main
+    // thread to SCHED_RR and 50 (medium) level. Otherwise, we're always below
+    // the launched threads (even -2).
+    //
+#ifdef LINUX_SCHED_RR
+    if (m_sudo)
+    {
+        struct sched_param sp;
+        sp.sched_priority = _PRIO_0;
+        PT_CALL(pthread_setschedparam(pthread_self(), SCHED_RR, &sp));
+    }
+#endif // LINUX_SCHED_RR
+#endif // PLATFORM_LINUX
+}
+
+// ################################################################################################
+
 // only called from the master state
 Universe* universe_create(lua_State* L)
 {
diff --git a/src/universe.h b/src/universe.h
index 38885cb..f4211af 100644
--- a/src/universe.h
+++ b/src/universe.h
@@ -119,9 +119,17 @@ class ProtectedAllocator : public AllocatorDefinition
 
 // everything regarding the Lanes universe is stored in that global structure
 // held as a full userdata in the master Lua state that required it for the first time
-// don't forget to initialize all members in LG_configure()
-struct Universe
+class Universe
 {
+    public:
+
+#ifdef PLATFORM_LINUX
+    // Linux needs to check, whether it's been run as root
+    bool const m_sudo{ geteuid() == 0 };
+#else
+    bool const m_sudo{ false };
+#endif // PLATFORM_LINUX
+
     // for verbose errors
     bool verboseErrors{ false };
 
@@ -155,6 +163,7 @@ struct Universe
     // require() serialization
     std::recursive_mutex require_cs;
 
+    // metatable unique identifiers
     std::atomic<lua_Integer> next_mt_id{ 1 };
 
 #if USE_DEBUG_SPEW()
@@ -165,6 +174,13 @@ struct Universe
     // After a lane has removed itself from the chain, it still performs some processing.
     // The terminal desinit sequence should wait for all such processing to terminate before force-killing threads
     std::atomic<int> selfdestructing_count{ 0 };
+
+    Universe();
+    ~Universe() = default;
+    Universe(Universe const&) = delete;
+    Universe(Universe&&) = delete;
+    Universe& operator=(Universe const&) = delete;
+    Universe& operator=(Universe&&) = delete;
 };
 
 // ################################################################################################