add: [concur] queue (TBD)

include/libconcur/bus.h

@@ -0,0 +1,16 @@
+/**
+ * \file libconcur/bus.h
+ * \author mutouyun (orz@orzz.org)
+ * \brief Define concurrent data bus.
+ * \date 2023-04-17
+ */
+#pragma once
+
+#include "libconcur/def.h"
+#include "libconcur/concurrent.h"
+
+LIBCONCUR_NAMESPACE_BEG_
+
+
+
+LIBCONCUR_NAMESPACE_END_

include/libconcur/def.h

@@ -29,6 +29,8 @@ enum : std::size_t {
 #else
     64,
 #endif
+
+  default_circle_buffer_size = 1024,
 };
 
 LIBCONCUR_NAMESPACE_END_

include/libconcur/queue.h

@@ -6,11 +6,74 @@
  */
 #pragma once
 
+#include <cstddef>
+
+#include "libimp/construct.h"
+#include "libimp/detect_plat.h"
+
+#include "libpmr/allocator.h"
+#include "libpmr/memory_resource.h"
+
 #include "libconcur/def.h"
-#include "libconcur/element.h"
+#include "libconcur/concurrent.h"
 
 LIBCONCUR_NAMESPACE_BEG_
 
+template <typename T, typename PRelationT, typename CRelationT>
+class queue {
+public:
+  using producer_relation_t = PRelationT;
+  using consumer_relation_t = CRelationT;
+  using model_type = prod_cons<trans::unicast, producer_relation_t, consumer_relation_t>;
+  using value_type = T;
 
+private:
+  struct data {
+    model_type model_;
+    typename concur::traits<model_type>::header header_;
+    element<value_type> elements_start_;
+
+    template <typename U>
+    data(U &&model) noexcept
+      : header_(std::forward<U>(model)) {}
+
+    /// \brief element<value_type> elements[0];
+    element<value_type> *elements() noexcept {
+      return &elements_start_;
+    }
+  };
+
+  data *init(index_t circ_size) noexcept {
+    if (!data_allocator_) {
+      return nullptr;
+    }
+    LIBIMP_TRY {
+      auto data_ptr = data_allocator_.allocate(sizeof(data) + (circ_size - 1) * sizeof(element<value_type>));
+      if (data_ptr == nullptr) {
+        return nullptr;
+      }
+      return ::LIBIMP::construct<data>(data_ptr, circ_size);
+    } LIBIMP_CATCH(...) {
+      return nullptr;
+    }
+  }
+
+  ::LIBPMR::allocator data_allocator_;
+  data *data_;
+  typename concur::traits<model_type>::context context_;
+
+public:
+  queue() = default;
+  queue(queue const &) = delete;
+  queue(queue &&) = delete;
+  queue &operator=(queue const &) = delete;
+  queue &operator=(queue &&) = delete;
+
+  template <typename MR, ::LIBPMR::verify_memory_resource<T> = true>
+  explicit queue(index_t circ_size = default_circle_buffer_size, 
+                 MR *memory_resource = ::LIBPMR::new_delete_resource::get()) noexcept
+    : data_allocator_(memory_resource)
+    , data_(init(circ_size)) {}
+};
 
 LIBCONCUR_NAMESPACE_END_

include/libpmr/allocator.h

@@ -47,7 +47,7 @@ class LIBIMP_EXPORT allocator {
     bool  valid() const noexcept override { return false; }
   };
 
-  template <typename MemRes, typename = void>
+  template <typename MemRes, typename = bool>
   class holder_memory_resource;
 
   /**
@@ -55,7 +55,7 @@ class LIBIMP_EXPORT allocator {
    * \tparam MR memory resource type
    */
   template <typename MR>
-  class holder_memory_resource<MR, is_memory_resource<MR>> : public holder_base {
+  class holder_memory_resource<MR, verify_memory_resource<MR>> : public holder_base {
     MR *p_mem_res_;
 
   public:
@@ -102,7 +102,7 @@ public:
 
   /// \brief Constructs a allocator from a memory resource pointer
   /// The lifetime of the pointer must be longer than that of allocator.
-  template <typename T, typename = is_memory_resource<T>>
+  template <typename T, verify_memory_resource<T> = true>
   allocator(T *p_mr) : allocator() {
     if (p_mr == nullptr) return;
     ::LIBIMP::construct<holder_memory_resource<T>>(holder_.data(), p_mr);

include/libpmr/memory_resource.h

@@ -35,9 +35,9 @@ struct has_deallocate<T,
   > : std::true_type {};
 
 template <typename T>
-using is_memory_resource = 
-  typename std::enable_if<has_allocate  <T>::value && 
-                          has_deallocate<T>::value>::type;
+using verify_memory_resource = 
+  std::enable_if_t<has_allocate  <T>::value && 
+                   has_deallocate<T>::value, bool>;
 
 /**
  * \brief A memory resource that uses the 

test/concur/test_concur_bus.cpp

@@ -0,0 +1,4 @@
+
+#include "gtest/gtest.h"
+
+#include "libconcur/bus.h"