feat: add lab-rv32i-freertos-allocator-resource card

include/freertos/memory_resource.hpp

@@ -0,0 +1,243 @@
+#ifndef FREERTOS_CPP_MEMORY_RESOURCE_HPP
+#define FREERTOS_CPP_MEMORY_RESOURCE_HPP
+
+#include <stddef.h>
+#include <stdint.h>
+
+extern "C"
+{
+#include "FreeRTOS.h"
+}
+
+namespace freertos
+{
+
+class MemoryResource final
+{
+public:
+    using Allocate = void *( * )( void *, size_t, size_t ) noexcept;
+    using Deallocate = void ( * )( void *, void *, size_t, size_t ) noexcept;
+
+    constexpr MemoryResource( void * context,
+                              Allocate allocate,
+                              Deallocate deallocate ) noexcept
+        : context_ { context },
+          allocate_ { allocate },
+          deallocate_ { deallocate }
+    {
+    }
+
+    void * allocate_bytes( size_t bytes, size_t alignment ) const noexcept
+    {
+        return allocate_( context_, bytes, alignment );
+    }
+
+    void deallocate_bytes( void * memory,
+                           size_t bytes,
+                           size_t alignment ) const noexcept
+    {
+        deallocate_( context_, memory, bytes, alignment );
+    }
+
+    constexpr void * context() const noexcept
+    {
+        return context_;
+    }
+
+    constexpr Allocate allocate_function() const noexcept
+    {
+        return allocate_;
+    }
+
+    constexpr Deallocate deallocate_function() const noexcept
+    {
+        return deallocate_;
+    }
+
+private:
+    void * context_;
+    Allocate allocate_;
+    Deallocate deallocate_;
+};
+
+constexpr bool valid_alignment( size_t alignment ) noexcept
+{
+    return alignment != 0U &&
+           ( alignment & ( alignment - 1U ) ) == 0U;
+}
+
+class HeapResource final
+{
+public:
+    MemoryResource resource() noexcept
+    {
+        return MemoryResource { this, &allocate, &deallocate };
+    }
+
+    constexpr size_t successful_allocations() const noexcept
+    {
+        return successful_allocations_;
+    }
+
+    constexpr size_t failed_allocations() const noexcept
+    {
+        return failed_allocations_;
+    }
+
+    constexpr size_t deallocations() const noexcept
+    {
+        return deallocations_;
+    }
+
+private:
+    static void * allocate( void * context,
+                            size_t bytes,
+                            size_t alignment ) noexcept
+    {
+        auto & self = *static_cast< HeapResource * >( context );
+        if( bytes == 0U || !valid_alignment( alignment ) ||
+            alignment > portBYTE_ALIGNMENT )
+        {
+            ++self.failed_allocations_;
+            return nullptr;
+        }
+
+        void * const memory = pvPortMalloc( bytes );
+        if( memory == nullptr )
+        {
+            ++self.failed_allocations_;
+        }
+        else
+        {
+            ++self.successful_allocations_;
+        }
+        return memory;
+    }
+
+    static void deallocate( void * context,
+                            void * memory,
+                            size_t,
+                            size_t ) noexcept
+    {
+        if( memory != nullptr )
+        {
+            auto & self = *static_cast< HeapResource * >( context );
+            vPortFree( memory );
+            ++self.deallocations_;
+        }
+    }
+
+    size_t successful_allocations_ {};
+    size_t failed_allocations_ {};
+    size_t deallocations_ {};
+};
+
+class StaticArenaResource final
+{
+public:
+    constexpr StaticArenaResource( uint8_t * storage,
+                                   size_t capacity,
+                                   size_t maximum_alignment ) noexcept
+        : storage_ { storage },
+          capacity_ { capacity },
+          maximum_alignment_ { maximum_alignment }
+    {
+    }
+
+    MemoryResource resource() noexcept
+    {
+        return MemoryResource { this, &allocate, &deallocate };
+    }
+
+    void reset() noexcept
+    {
+        used_ = 0U;
+        ++resets_;
+    }
+
+    constexpr size_t used() const noexcept
+    {
+        return used_;
+    }
+
+    constexpr size_t remaining() const noexcept
+    {
+        return capacity_ - used_;
+    }
+
+    constexpr size_t successful_allocations() const noexcept
+    {
+        return successful_allocations_;
+    }
+
+    constexpr size_t failed_allocations() const noexcept
+    {
+        return failed_allocations_;
+    }
+
+    constexpr size_t resets() const noexcept
+    {
+        return resets_;
+    }
+
+    bool owns( const void * memory ) const noexcept
+    {
+        const uintptr_t address = reinterpret_cast< uintptr_t >( memory );
+        const uintptr_t first = reinterpret_cast< uintptr_t >( storage_ );
+        return address >= first && address < first + capacity_;
+    }
+
+private:
+    static void * allocate( void * context,
+                            size_t bytes,
+                            size_t alignment ) noexcept
+    {
+        auto & self = *static_cast< StaticArenaResource * >( context );
+        if( bytes == 0U || !valid_alignment( alignment ) ||
+            alignment > self.maximum_alignment_ )
+        {
+            ++self.failed_allocations_;
+            return nullptr;
+        }
+
+        const uintptr_t base =
+            reinterpret_cast< uintptr_t >( self.storage_ );
+        const uintptr_t current = base + self.used_;
+        if( current > UINTPTR_MAX - ( alignment - 1U ) )
+        {
+            ++self.failed_allocations_;
+            return nullptr;
+        }
+        const uintptr_t aligned =
+            ( current + alignment - 1U ) & ~( alignment - 1U );
+        const size_t padding = static_cast< size_t >( aligned - current );
+        const size_t remaining = self.capacity_ - self.used_;
+        if( padding > remaining || bytes > remaining - padding )
+        {
+            ++self.failed_allocations_;
+            return nullptr;
+        }
+
+        self.used_ += padding + bytes;
+        ++self.successful_allocations_;
+        return reinterpret_cast< void * >( aligned );
+    }
+
+    static void deallocate( void *, void *, size_t, size_t ) noexcept
+    {
+        /* Monotonic arena: individual deallocation deliberately does nothing. */
+    }
+
+    uint8_t * storage_;
+    size_t capacity_;
+    size_t maximum_alignment_;
+    size_t used_ {};
+    size_t successful_allocations_ {};
+    size_t failed_allocations_ {};
+    size_t resets_ {};
+};
+
+} // namespace freertos
+
+#endif
+