From 7070a9364c42bce12047d9bd4f6e0314caff8bdd Mon Sep 17 00:00:00 2001
From: ADAM David Alan Martin <adam@recursive.engineer>
Date: Wed, 15 May 2024 22:26:13 -0400
Subject: [PATCH] Start moving towards the alignment solution>

Some of this needs to be branched out.
---
 Memory/Blob.h       | 15 +++++++++++----
 Memory/DataChain.h  |  4 ++--
 Memory/ThreadSlab.h |  6 +++---
 3 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/Memory/Blob.h b/Memory/Blob.h
index 00e765e..a92f073 100644
--- a/Memory/Blob.h
+++ b/Memory/Blob.h
@@ -8,9 +8,10 @@ static_assert( __cplusplus > 2020'99 );
 
 #include <memory>
 
+#include <Alepha/swappable.h>
+#include <Alepha/Exception.h>
+
 #include "Buffer.h"
-#include "swappable.h"
-#include "Exception.h"
 //#include "threading.h"
 #include "error.h"
 
@@ -221,11 +222,17 @@ namespace Alepha::Hydrogen  ::detail::  Blob_m
 			 * inside a large single physical backing.  This helps maintain zero-copy semantics.
 			 *
 			 * @param amount The amount of data to carve off.
-			 * @return A new `Blob` object referring to the same physical data, scoped to `amount` bytes.
+			 * @param alignment The size alignment that the new base should be at (the extra padding is
+			 * considered part of the resulting `Blob`).
+			 * @return A new `Blob` object referring to the same physical data, scoped to `amount` bytes (with
+			 * possible extra space, due to alignment).
 			 */
 			Blob
-			carveHead( const std::size_t amount )
+			carveHead( const std::size_t unalignedAmount, Alignment alignment= Alignment{ 1 } )
 			{
+				assert( std::popcount( alignment.amt ) == 1 );
+				// TODO: Consider arithmetic overflow, here.
+				const std::size_t amount= alignTo( ( reinterpret_cast< std::uintptr_t >( data() ) % alignment.amt ) + unalignedAmount, alignment );
 				if( amount > size() ) throw DataCarveTooLargeError( data(), amount, size() );
 				if( not storage )
 				{
diff --git a/Memory/DataChain.h b/Memory/DataChain.h
index 6f33edd..0f5853e 100644
--- a/Memory/DataChain.h
+++ b/Memory/DataChain.h
@@ -52,7 +52,7 @@ namespace Alepha::inline Cavorite  ::detail::  DataChain_m
 
 					friend DataChain;
 
-					explicit Iterator( const ChainIter pos, cosnt std::size_t offset ) noexcept : pos( pos ), offset( offset ) {}
+					explicit Iterator( const ChainIter pos, const std::size_t offset ) noexcept : pos( pos ), offset( offset ) {}
 
 				public:
 					auto
@@ -165,7 +165,7 @@ namespace Alepha::inline Cavorite  ::detail::  DataChain_m
 						std::copy_n( std::prev( end(), amount ), amount, rv.byte_data() );
 
 						return rv;
-							
+					}
 			};
 	};
 }
diff --git a/Memory/ThreadSlab.h b/Memory/ThreadSlab.h
index 40d9cea..e3bd28d 100644
--- a/Memory/ThreadSlab.h
+++ b/Memory/ThreadSlab.h
@@ -58,15 +58,15 @@ namespace Alepha::Hydrogen::Memory  ::detail::  ThreadSlab_m
 			{
 				// TODO: Alignment?
 				const std::size_t req= amt + sizeof( Blob::StorageReservation );
+				if( req > C::slabSize ) throw std::bad_alloc{}; //{ "Unable to allocate larger than the slab size." };
 				if( slab.size() < req ) slab.reset( std::max( req, C::slabSize ) );
 
 				std::cerr << "Reporting " << slab.reservation().use_count() << " living allocations when "
 						<< (void *) this << " made an allocation." << std::endl;
 
-				auto next= slab.carveHead( req );
-				new ( &next.template as< Blob::StorageReservation >() ) Blob::StorageReservation{ next.reservation() };
+				auto next= slab.carveHead( req, Alignment{ sizeof( Blob::StorageReservation ) } );
 				const auto rv= reinterpret_cast< T * >( &next.template as< Blob::StorageReservation >() + 1 );
-				next.reset();
+				new ( &next.template as< Blob::StorageReservation >() ) Blob::StorageReservation{ std::move( next.reservation() ) };
 
 				std::cerr << "Reporting " << slab.reservation().use_count() << " living allocations when "
 						<< (void *) this << " made an allocation." << std::endl;