os-semaphore.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_SEMAPHORE_H_
#define CMSIS_PLUS_RTOS_OS_SEMAPHORE_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 semaphore : public internal::object_named_system
    {
    public:

      using count_t = int16_t;

      static constexpr count_t max_count_value = 0x7FFF;

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

      class attributes : public internal::attributes_clocked
      {
      public:

        constexpr
        attributes ();

      protected:

        constexpr
        attributes (count_t max_value, count_t initial_value = 0);

      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.
        count_t sm_max_value = 1;

        count_t sm_initial_value = 0;

        // Add more attributes here.

      }; /* class attributes */

      // ======================================================================
      class attributes_binary : public attributes
      {
      public:

        constexpr
        attributes_binary (count_t initial_value);

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

        ~attributes_binary () = default;

      }; /* class attributes_binary */

      static const attributes_binary initializer_binary;

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

      class attributes_counting : public attributes
      {
      public:

        constexpr
        attributes_counting (count_t max_value, count_t initial_value);

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

        ~attributes_counting () = default;

      }; /* class attributes_counting */

      // ======================================================================
      semaphore (const attributes& attr = initializer_binary);

      semaphore (const char* name, const attributes& attr = initializer_binary);

    protected:

      semaphore (const char* name, const count_t max_value,
                 const count_t initial_value, const attributes& attr =
                     initializer_binary);

    public:

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

      ~semaphore ();

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

    public:

      result_t
      post (void);

      result_t
      wait (void);

      result_t
      try_wait (void);

      result_t
      timed_wait (clock::duration_t timeout);

      count_t
      value (void) const;

      result_t
      reset (void);

      count_t
      initial_value (void) const;

      count_t
      max_value (void) const;

    protected:

      void
      internal_init_ (void);

      bool
      internal_try_wait_ (void);

    protected:

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

#if defined(OS_USE_RTOS_PORT_SEMAPHORE)
      friend class port::semaphore;
      os_semaphore_port_data_t port_;
#endif

      // Constant set during construction.
      const count_t max_value_ = max_count_value;

      const count_t initial_value_ = 0;

      // Can be updated in different contexts (interrupts or threads)
      volatile count_t count_ = 0;

      // Add more internal data.

    };

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

    class semaphore_binary : public semaphore
    {
    public:

      semaphore_binary (const count_t initial_value);

      semaphore_binary (const char* name, const count_t initial_value);

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

      ~semaphore_binary ();

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

    };

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

    class semaphore_counting : public semaphore
    {
    public:

      semaphore_counting (const count_t max_value, const count_t initial_value);

      semaphore_counting (const char* name, const count_t max_value,
                          const count_t initial_value);

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

      ~semaphore_counting ();

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

    };

#pragma GCC diagnostic pop

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

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

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

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

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

    constexpr
    semaphore::attributes::attributes (count_t max_value, count_t initial_value) :
        sm_max_value (max_value), //
        sm_initial_value (initial_value)
    {
      ;
    }

    // ========================================================================
    constexpr
    semaphore::attributes_binary::attributes_binary (count_t initial_value) :
        attributes
          { 1, initial_value } // Use the protected constructor.
    {
      ;
    }

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

    constexpr
    semaphore::attributes_counting::attributes_counting (count_t max_value,
                                                         count_t initial_value) :
        attributes
          { max_value, initial_value } // Use the protected constructor.
    {
      ;
    }

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

    inline
    semaphore::semaphore (const attributes& attr) :
        semaphore
          { nullptr, attr }
    {
      ;
    }

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

    inline semaphore::count_t
    semaphore::initial_value (void) const
    {
      return initial_value_;
    }

    inline semaphore::count_t
    semaphore::max_value (void) const
    {
      return max_value_;
    }

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

    inline
    semaphore_binary::semaphore_binary (const count_t initial_value) :
        semaphore
          { nullptr, 1, initial_value, initializer_binary }
    {
      ;
    }

    inline
    semaphore_binary::semaphore_binary (const char* name,
                                        const count_t initial_value) :
        semaphore
          { name, 1, initial_value }
    {
      ;
    }

    inline
    semaphore_binary::~semaphore_binary ()
    {
      ;
    }

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

    inline
    semaphore_counting::semaphore_counting (const count_t max_value,
                                            const count_t initial_value) :
        semaphore
          { nullptr, max_value, initial_value }
    {
      ;
    }

    inline
    semaphore_counting::semaphore_counting (const char* name,
                                            const count_t max_value,
                                            const count_t initial_value) :
        semaphore
          { name, max_value, initial_value }
    {
      ;
    }

    inline
    semaphore_counting::~semaphore_counting ()
    {
      ;
    }

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

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

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

#endif /* __cplusplus */

#endif /* CMSIS_PLUS_RTOS_OS_SEMAPHORE_H_ */