os-mutex.h

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/*
 * This file is part of the µOS++ distribution.
 *   (https://github.com/micro-os-plus)
 * Copyright (c) 2016 Liviu Ionescu.
 *
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation
 * files (the "Software"), to deal in the Software without
 * restriction, including without limitation the rights to use,
 * copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom
 * the Software is furnished to do so, subject to the following
 * conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */

#ifndef CMSIS_PLUS_RTOS_OS_MUTEX_H_
#define CMSIS_PLUS_RTOS_OS_MUTEX_H_

// ----------------------------------------------------------------------------

#if defined(__cplusplus)

#include <cmsis-plus/rtos/os-decls.h>

// ----------------------------------------------------------------------------

namespace os
{
  namespace rtos
  {
    // ========================================================================

#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Wpadded"

    class mutex : public internal::object_named_system
    {
    public:

      using protocol_t = uint8_t;

      struct protocol
      {
        enum
          : protocol_t
            {
              none = 0,

              inherit = 1,

              protect = 2,

              default_ = inherit,

              max_ = protect,
        };
      };

      using robustness_t = uint8_t;

      struct robustness
      {
        enum
          : robustness_t
            {
              stalled = 0,

              robust = 1,

              default_ = stalled,

              max_ = robust,
        };
      };

      using type_t = uint8_t;

      struct type
      {
        enum
          : type_t
            {
              normal = 0,
              errorcheck = 1,
              recursive = 2,

              default_ = normal,

              max_ = recursive,
        };
      };

      using count_t = uint16_t;

      static constexpr count_t max_count = 0xFFFF;

      // ======================================================================

      class attributes : public internal::attributes_clocked
      {
      public:

        constexpr
        attributes ();

      protected:

        constexpr
        attributes (type_t type);

      public:

        // The rule of five.
        attributes (const attributes&) = default;
        attributes (attributes&&) = default;
        attributes&
        operator= (const attributes&) = default;
        attributes&
        operator= (attributes&&) = default;

        ~attributes () = default;

      public:

        // Public members; no accessors and mutators required.
        // Warning: must match the type & order of the C file header.
        thread::priority_t mx_priority_ceiling = thread::priority::highest;

        protocol_t mx_protocol = protocol::default_;

        robustness_t mx_robustness = robustness::stalled;

        type_t mx_type = type::default_;

        count_t mx_max_count = max_count;

        // Add more attributes here.

      }; /* class attributes */

      static const attributes initializer_normal;

      // ======================================================================

      class attributes_recursive : public attributes
      {
      public:

        constexpr
        attributes_recursive ();

        // The rule of five.
        attributes_recursive (const attributes_recursive&) = default;
        attributes_recursive (attributes_recursive&&) = default;
        attributes_recursive&
        operator= (const attributes_recursive&) = default;
        attributes_recursive&
        operator= (attributes_recursive&&) = default;

        ~attributes_recursive () = default;

      }; /* class attributes_recursive */

      static const attributes_recursive initializer_recursive;

      mutex (const attributes& attr = initializer_normal);

      mutex (const char* name, const attributes& attr = initializer_normal);

      // The rule of five.
      mutex (const mutex&) = delete;
      mutex (mutex&&) = delete;
      mutex&
      operator= (const mutex&) = delete;
      mutex&
      operator= (mutex&&) = delete;

      ~mutex ();

      bool
      operator== (const mutex& rhs) const;

    public:

      result_t
      lock (void);

      result_t
      try_lock (void);

      result_t
      timed_lock (clock::duration_t timeout);

      result_t
      unlock (void);

      thread::priority_t
      prio_ceiling (void) const;

      result_t
      prio_ceiling (thread::priority_t prio_ceiling,
                    thread::priority_t* old_prio_ceiling = nullptr);

      result_t
      consistent (void);

      thread*
      owner (void);

      type_t
      type (void);

      protocol_t
      protocol (void);

      robustness_t
      robustness (void);

      result_t
      reset (void);

    protected:

      friend class thread;

      void
      internal_init_ (void);

      result_t
      internal_try_lock_ (thread* th);

      result_t
      internal_unlock_ (thread* th);

      void
      internal_mark_owner_dead_ (void);

    protected:

      // Can be updated in different thread contexts.
      thread* volatile owner_ = nullptr;

#if !defined(OS_USE_RTOS_PORT_MUTEX)
      internal::waiting_threads_list list_;
      clock* clock_ = nullptr;
#endif

    public:

      // Intrusive node used to link this mutex to the owning thread.
      // This is used for priority inheritance and robustness.
      utils::double_list_links owner_links_;

    protected:

#if defined(OS_USE_RTOS_PORT_MUTEX)
      friend class port::mutex;
      os_mutex_port_data_t port_;
#endif

      // Can be updated in different thread contexts.
      volatile count_t count_ = 0;

      // Can be updated in different thread contexts.
      volatile thread::priority_t initial_prio_ceiling_ =
          thread::priority::highest;
      volatile thread::priority_t prio_ceiling_ = thread::priority::highest;
      volatile thread::priority_t boosted_prio_ = thread::priority::none;

      bool owner_dead_ = false;
      bool consistent_ = true;
      bool recoverable_ = true;

      // Constants set during construction.
      const type_t type_; // normal, errorcheck, recursive
      const protocol_t protocol_; // none, inherit, protect
      const robustness_t robustness_; // stalled, robust
      const count_t max_count_;

      // Add more internal data.

    };

    class mutex_recursive : public mutex
    {
    public:

      mutex_recursive (const attributes& attr = initializer_recursive);

      mutex_recursive (const char* name, const attributes& attr =
                           initializer_recursive);

      // The rule of five.
      mutex_recursive (const mutex_recursive&) = delete;
      mutex_recursive (mutex_recursive&&) = delete;
      mutex_recursive&
      operator= (const mutex_recursive&) = delete;
      mutex_recursive&
      operator= (mutex_recursive&&) = delete;

      ~mutex_recursive ();

      bool
      operator== (const mutex_recursive& rhs) const;

    };

#pragma GCC diagnostic pop

  // ==========================================================================

  } /* namespace rtos */
} /* namespace os */

// ===== Inline & template implementations ====================================

namespace os
{
  namespace rtos
  {

    // ========================================================================

    constexpr
    mutex::attributes::attributes ()
    {
      ;
    }

    constexpr
    mutex::attributes::attributes (type_t type) :
        mx_type (type)
    {
      ;
    }

    // ========================================================================
    constexpr
    mutex::attributes_recursive::attributes_recursive () :
        attributes
          { type::recursive } // Use the protected constructor.
    {
      ;
    }

    // ========================================================================

    inline bool
    mutex::operator== (const mutex& rhs) const
    {
      return this == &rhs;
    }

    inline thread*
    mutex::owner (void)
    {
      return owner_;
    }

    inline mutex::type_t
    mutex::type (void)
    {
      return type_;
    }

    inline mutex::protocol_t
    mutex::protocol (void)
    {
      return protocol_;
    }

    inline mutex::robustness_t
    mutex::robustness (void)
    {
      return robustness_;
    }

    // ========================================================================

    inline
    mutex_recursive::mutex_recursive (const attributes& attr) :
        mutex
          { attr }
    {
      ;
    }

    inline
    mutex_recursive::mutex_recursive (const char* name, const attributes& attr) :
        mutex
          { name, attr }
    {
      ;
    }

    inline
    mutex_recursive::~mutex_recursive ()
    {
      ;
    }

    inline bool
    mutex_recursive::operator== (const mutex_recursive& rhs) const
    {
      return this == &rhs;
    }

  } /* namespace rtos */
} /* namespace os */

// ----------------------------------------------------------------------------

#endif /* __cplusplus */

#endif /* CMSIS_PLUS_RTOS_OS_MUTEX_H_ */