cpukit/librcxx: Add a C++ thread interface with attributes

2 files changed, 492 insertions, 0 deletions

diff --git a/cpukit/librtemscxx/error.cpp b/cpukit/librtemscxx/error.cpp
new file mode 100644
index 0000000000..ba46a8c2a5
--- /dev/null
+++ b/cpukit/librtemscxx/error.cpp
@@ -0,0 +1,76 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+
+/*
+ * Copyright (C) 2020 Chris Johns (http://contemporary.software)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <rtems/error.hpp>
+
+namespace rtems
+{
+  runtime_error::runtime_error (const rtems_status_code sc)
+    : std::runtime_error (::rtems_status_text (sc)),
+      sc (sc)
+  {
+  }
+
+  runtime_error::runtime_error (const rtems_status_code sc,
+                                const std::string&      what)
+    : std::runtime_error (what + ": " + ::rtems_status_text (sc)),
+      sc (sc)
+  {
+  }
+
+  runtime_error::runtime_error (const rtems_status_code sc,
+                                const char*             what)
+    : std::runtime_error (std::string (what) + ": " + ::rtems_status_text (sc)),
+      sc (sc)
+  {
+  }
+
+  runtime_error::~runtime_error()
+  {
+  }
+
+  void
+  runtime_error_check (const rtems_status_code sc)
+  {
+    if (sc != RTEMS_SUCCESSFUL)
+      throw runtime_error (sc);
+  }
+
+  void
+  runtime_error_check (const rtems_status_code sc, const std::string& what)
+  {
+    if (sc != RTEMS_SUCCESSFUL)
+      throw runtime_error (sc, what);
+  }
+
+  void
+  runtime_error_check (const rtems_status_code sc, const char* what)
+  {
+    if (sc != RTEMS_SUCCESSFUL)
+      throw runtime_error (sc, what);
+  }
+};
diff --git a/cpukit/librtemscxx/thread.cpp b/cpukit/librtemscxx/thread.cpp
new file mode 100644
index 0000000000..11bf3df230
--- /dev/null
+++ b/cpukit/librtemscxx/thread.cpp
@@ -0,0 +1,416 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+
+/*
+ * Copyright (C) 2020 Chris Johns (http://contemporary.software)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#if !defined(_GNU_SOURCE)
+#define _GNU_SOURCE
+#endif
+
+#include <system_error>
+
+#include <rtems/error.hpp>
+#include <rtems/thread.hpp>
+
+#include <pthread.h>
+
+#include <rtems.h>
+
+#if HAVE_GET_SCHEDULER_NAME
+extern "C" bool get_scheduler_name (rtems_id sid, char* name);
+#endif
+
+#if HAVE_GET_SCHEDULER_NAME
+bool get_scheduler_name (rtems_id sid, char* name)
+{
+  name[0] = 'N';
+  name[1] = 'O';
+  name[2] = 'P';
+  name[3] = '\0';
+  return true;
+}
+#endif
+
+namespace rtems
+{
+  namespace thread
+  {
+    void
+    system_error_check (int ec, const char* what)
+    {
+      if (ec != 0)
+        throw std::system_error (ec, std::system_category(), what);
+    }
+
+    attributes::attributes ()
+      : priority (-1),
+        stack_size (RTEMS_MINIMUM_STACK_SIZE),
+        attr (sched_inherit),
+        policy (sched_fifo)
+    {
+      update ();
+    }
+
+    attributes::attributes (const attributes& attr)
+      : name (attr.name),
+        priority (attr.priority),
+        stack_size (attr.stack_size),
+        scheduler (attr.scheduler),
+        attr (attr.attr),
+        policy (attr.policy)
+    {
+    }
+
+    void
+    attributes::set_name (const std::string& name_)
+    {
+      name = name_;
+    }
+
+    void
+    attributes::set_name (const char* name_)
+    {
+      name = name_;
+    }
+
+    const std::string&
+    attributes::get_name () const
+    {
+      return name;
+    }
+
+    void
+    attributes::set_priority (int priority_)
+    {
+      priority = priority_;
+    }
+
+    int
+    attributes::get_priority () const
+    {
+      return priority;
+    }
+
+    void
+    attributes::set_stack_size(size_t size)
+    {
+      stack_size = size;
+    }
+
+    size_t
+    attributes::get_stack_size () const
+    {
+      return stack_size;
+    }
+
+    void
+    attributes::set_scheduler (const std::string& scheduler_)
+    {
+      scheduler = scheduler_;
+    }
+
+    void
+    attributes::set_scheduler (const char* scheduler_)
+    {
+      scheduler = scheduler_;
+    }
+
+    const std::string&
+    attributes::get_scheduler ()
+    {
+      return scheduler;
+    }
+
+    attributes::sched_attr
+    attributes::get_scheduler_attr () const
+    {
+      return attr;
+    }
+
+    void
+    attributes::set_scheduler_policy (sched_policy policy_)
+    {
+      attr = sched_explicit;
+      policy = policy_;
+    }
+
+    attributes::sched_policy
+    attributes::get_scheduler_policy () const
+    {
+      return policy;
+    }
+
+    void
+    attributes::commit ()
+    {
+      pthread_t pid = ::pthread_self ();
+
+      system_error_check (::pthread_setname_np (pid, name.c_str ()),
+                          "getting name");
+
+      int                spolicy;
+      struct sched_param sched_param;
+
+      system_error_check (::pthread_getschedparam (::pthread_self (),
+                                                   &spolicy,
+                                                   &sched_param),
+                          "getting scheduler parameters");
+
+      switch (policy) {
+      case sched_other:
+        spolicy = SCHED_OTHER;
+        break;
+      case sched_fifo:
+        spolicy = SCHED_FIFO;
+        break;
+      case sched_roundrobin:
+        spolicy = SCHED_RR;
+        break;
+      case sched_sporadic:
+        spolicy = SCHED_SPORADIC;
+        break;
+      default:
+        system_error_check (EINVAL, "get scheduler policy");
+        break;
+      }
+
+      sched_param.sched_priority = priority;
+
+      system_error_check (::pthread_setschedparam (::pthread_self (),
+                                                   spolicy,
+                                                   &sched_param),
+                          "getting scheduler parameters");
+
+      if (!scheduler.empty ()) {
+        char sname[4] = { ' ', ' ', ' ', ' ' };
+        for (size_t c = 0; c < sizeof (sname); ++c) {
+          if (c >= scheduler.length ())
+            break;
+          sname[c] = scheduler[c];
+        }
+        rtems_name scheduler_name = rtems_build_name (sname[0],
+                                                      sname[1],
+                                                      sname[2],
+                                                      sname[3]);
+        rtems_id scheduler_id;
+        runtime_error_check (::rtems_scheduler_ident (scheduler_name,
+                                                      &scheduler_id),
+                             "get scheduler id");
+        // runtime_error_check (::rtems_task_set_scheduler (RTEMS_SELF,
+        //                                                  scheduler_id,
+        //                                                  1),
+        //                      "set scheduler id");
+      }
+    }
+
+    void
+    attributes::update ()
+    {
+      char buf[32];
+      system_error_check (::pthread_getname_np (::pthread_self (),
+                                                buf,
+                                                sizeof (buf)),
+                          "getting name");
+      name = buf;
+
+      int                spolicy;
+      struct sched_param sched_param;
+      system_error_check (::pthread_getschedparam (::pthread_self (),
+                                                   &spolicy,
+                                                   &sched_param),
+                          "getting scheduler parameters");
+
+      switch (spolicy) {
+      case SCHED_OTHER:
+        policy = sched_other;
+        break;
+      case SCHED_FIFO:
+        policy = sched_fifo;
+        break;
+      case SCHED_RR:
+        policy = sched_roundrobin;
+        break;
+      case SCHED_SPORADIC:
+        policy = sched_sporadic;
+        break;
+      default:
+        system_error_check (EINVAL, "get scheduler policy");
+        break;
+      }
+      priority = sched_param.sched_priority;
+
+      pthread_attr_t pattr;
+      system_error_check (::pthread_getattr_np (::pthread_self (), &pattr),
+                          "getting thread attributes");
+      system_error_check (::pthread_attr_getstacksize (&pattr, &stack_size),
+                          "getting stack size");
+      int inheritsched = 0;
+      system_error_check (::pthread_attr_getinheritsched (&pattr, &inheritsched),
+                          "getting inherited sheduler attribute");
+      switch (inheritsched) {
+      case PTHREAD_INHERIT_SCHED:
+        attr = sched_inherit;
+        break;
+      case PTHREAD_EXPLICIT_SCHED:
+        attr = sched_explicit;
+        break;
+      default:
+        system_error_check (EINVAL, "get scheduler attribute");
+        break;
+      }
+
+      rtems_id scheduler_id;
+      runtime_error_check (::rtems_task_get_scheduler (RTEMS_SELF, &scheduler_id));
+#if HAVE_GET_SCHEDULER_NAME
+      char name[5];
+      if (!get_scheduler_name (scheduler_id, &name[0]))
+        system_error_check (ENOENT, "get scheduler name");
+      scheduler = name;
+#endif
+    }
+
+    attributes&
+    attributes::operator= (const attributes& other)
+    {
+      name = other.name;
+      priority = other.priority;
+      stack_size = other.stack_size;
+      attr = other.attr;
+      policy = other.policy;
+      return *this;
+    }
+
+    bool
+    attributes::operator== (const attributes& other) const
+    {
+      return
+        name == other.name &&
+        priority == other.priority &&
+        stack_size == other.stack_size &&
+        attr == other.attr &&
+        policy == other.policy;
+    }
+
+    void*
+    thread_generic_entry (void* arg)
+    {
+      thread::state_ptr s{ static_cast<thread::state_base*> (arg) };
+      try {
+        s->run ();
+      } catch (...) {
+        std::terminate ();
+      }
+      return nullptr;
+    }
+
+    thread&
+    thread::operator= (thread&& thread_)
+    {
+      if (joinable ())
+        std::terminate ();
+      swap(thread_);
+      return *this;
+    }
+
+    void
+    thread::swap(thread& thread_) noexcept
+    {
+      std::swap(id_, thread_.id_);
+    }
+
+    bool
+    thread::joinable() const noexcept
+    {
+      return !(id_ == id());
+    }
+
+    thread::state_base::~state_base () = default;
+
+    void
+    thread::start_thread (thread::state_ptr s)
+    {
+      const attributes attr = s->get_attributes ();
+
+      pthread_attr_t pattr;
+
+      system_error_check (::pthread_attr_init (&pattr),
+                          "attribute init");
+
+      system_error_check (::pthread_attr_setdetachstate (&pattr,
+                                                         PTHREAD_CREATE_DETACHED),
+                          "set detached state");
+
+      struct sched_param param;
+      param.sched_priority = attr.get_priority ();
+      system_error_check (::pthread_attr_setschedparam (&pattr, &param),
+                          "set ");
+
+      int spolicy;
+      switch (attr.get_scheduler_policy ()) {
+      case attributes::sched_other:
+        spolicy = SCHED_OTHER;
+        break;
+      case attributes::sched_roundrobin:
+        spolicy = SCHED_RR;
+        break;
+      case attributes::sched_sporadic:
+        spolicy = SCHED_SPORADIC;
+        break;
+      default:
+        spolicy = SCHED_FIFO;
+        break;
+      }
+      system_error_check (::pthread_attr_setschedpolicy (&pattr, spolicy),
+                          "set scheduler policy");
+
+      if (attr.get_scheduler_attr () == attributes::sched_inherit)
+        ::pthread_attr_setinheritsched (&pattr, PTHREAD_INHERIT_SCHED);
+      else
+        ::pthread_attr_setinheritsched (&pattr, PTHREAD_EXPLICIT_SCHED);
+
+      system_error_check (::pthread_attr_setstacksize(&pattr,
+                                                      attr.get_stack_size ()),
+                          "set stack size");
+
+      /*
+       * Hold the new thread in the state's run handler until the rest
+       * of the thread is set up after the create call.
+       */
+      system_error_check (::pthread_create (&id_.id_,
+                                            &pattr,
+                                            thread_generic_entry,
+                                            s.get ()),
+                          "create thread");
+
+      system_error_check (::pthread_setname_np (id_.id_,
+                                                attr.get_name ().c_str ()),
+                          "setting thread name");
+
+      ::pthread_attr_destroy (&pattr);
+
+      s.release ();
+    };
+  };
+};