Avoid serialization.

A great benefit of this is that the program doesn't need to COPY the
data from the file view to the struct.

3 files changed, 40 insertions, 82 deletions

diff --git a/c/data.cpp b/c/data.cpp
index 1a78ef2..fe348e7 100644
--- a/c/data.cpp
+++ b/c/data.cpp
@@ -18,7 +18,7 @@ inline unsigned char* BufToVal(unsigned char* const buf, T& val)
 	return buf+sizeof(val);
 }
 
-DatView::DatView(const wchar_t* const filename, const size_t cb)
+FileView::FileView(const wchar_t* const filename, const size_t cb)
 {
 	hf = CreateFile(filename, GENERIC_READ|GENERIC_WRITE,
 	    0, nullptr, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, nullptr);
@@ -39,12 +39,12 @@ DatView::DatView(const wchar_t* const filename, const size_t cb)
 	if (!hm)
 		throw Win32Error{};
 
-	view = MapViewOfFile(hm, FILE_MAP_ALL_ACCESS, 0, 0, 0);
+	view = reinterpret_cast<unsigned char*>(MapViewOfFile(hm, FILE_MAP_ALL_ACCESS, 0, 0, 0));
 	if (!view)
 		throw Win32Error{};
 }
 
-DatView::~DatView()
+FileView::~FileView()
 {
 	FlushViewOfFile(view, 0);
 	UnmapViewOfFile(view);
@@ -52,31 +52,14 @@ DatView::~DatView()
 	CloseHandle(hf);
 }
 
-unsigned char* Serialize(const ElvData& e, unsigned char* buf)
+void Write(unsigned char* buf, const ElvData& e)
 {
-	unsigned char version = 'a';
-	buf = ValToBuf(version, buf);
-	buf = ValToBuf(e.rating, buf);
-	buf = ValToBuf(e.bWatched, buf);
-	buf = ValToBuf(e.bTVOriginal, buf);
-	buf = ValToBuf(e.sRating, buf);
-	buf = ValToBuf(e.siEp, buf);
-	buf = ValToBuf(e.title, buf);
-	return buf;
+	memcpy(buf, reinterpret_cast<const unsigned char*>(&e), sizeof(e));
 }
 
-unsigned char* Unserialize(ElvData& e, unsigned char* buf)
+ElvData* Read(unsigned char* const buf)
 {
-	unsigned char version;
-	buf = BufToVal(buf, version);
-	if (version != 'a')
+	if (buf[0] != 'a')
 		return nullptr;
-
-	buf = BufToVal(buf, e.rating);
-	buf = BufToVal(buf, e.bWatched);
-	buf = BufToVal(buf, e.bTVOriginal);
-	buf = BufToVal(buf, e.sRating);
-	buf = BufToVal(buf, e.siEp);
-	buf = BufToVal(buf, e.title);
-	return buf;
+	return reinterpret_cast<ElvData*>(buf);
 }
diff --git a/c/data.h b/c/data.h
index 91e34d9..4e25251 100644
--- a/c/data.h
+++ b/c/data.h
@@ -5,14 +5,18 @@
 #include "util.h"
 #include "wcharptr.h"
 
+/* ElvData and DlvData are written as-is to disk; note the careful
+ * alignment. */
+
 struct ElvData
 {
-	int rating = 0;
-	bool bWatched = false;
-	bool bTVOriginal = false;
-	wchar_t sRating[3] = {0};
-	wchar_t siEp[5] = {0};
-	wchar_t title[128] = {0};
+	unsigned char version = 'a';	/* 0-1 */
+	unsigned char rating = 0;	/* 1-2 */
+	unsigned char bWatched = 0;	/* 2-3 */
+	unsigned char bTVOriginal = 0;	/* 3-4 */
+	wchar_t sRating[4] = {0};	/* 4-12 */
+	wchar_t siEp[6] = {0};		/* 12-24 */
+	wchar_t title[128] = {0};	/* 24-280 */
 };
 
 struct DlvData
@@ -24,19 +28,19 @@ struct DlvData
 	wchar_t wiki[128] = {0};
 };
 
-struct DatView
+struct FileView
 {
-	DatView(const wchar_t* filename, size_t cb);
-	~DatView();
+	FileView(const wchar_t* filename, size_t cb);
+	~FileView();
+	inline operator unsigned char*() { return view; }
 	HANDLE hf;
 	HANDLE hm;
-	void* view;
+	unsigned char* view;
 	/* TODO: Handle exceptions on read and write... */
 };
 
-constexpr size_t CB_SERIALIZE_ELVDATA = 1+sizeof(ElvData);
-unsigned char* Serialize(const ElvData& e, unsigned char* buf);
-unsigned char* Unserialize(ElvData& e, unsigned char* buf);
+void Write(unsigned char* buf, const ElvData& e);
+ElvData* Read(unsigned char* buf);
 
 inline int FromWeb(const int iEp, ElvData& e, DlvData& d) noexcept
 {
@@ -57,7 +61,7 @@ inline bool FromProlog(const int iEp, ElvData& e) noexcept
 	else
 		return false;
 
-	if (Pl("episode_data","episode_rating",iEp,&e.rating))
+	if (Pl("episode_data","episode_rating",iEp,reinterpret_cast<int*>(&e.rating)))
 		Swprintf(e.sRating, L"%d", e.rating);
 
 	if (Pl("episode_data","tv_original",iEp))
diff --git a/c/test.cpp b/c/test.cpp
index fb5d44d..abb03b3 100644
--- a/c/test.cpp
+++ b/c/test.cpp
@@ -47,59 +47,31 @@ TESTS
 			FAIL("date is not correct");
 	}
 
-	TEST(Serialization)
-	{
-		ElvData e1;
-		FromProlog(6, e1);
-
-		unsigned char buf[CB_SERIALIZE_ELVDATA];
-		Serialize(e1, buf);
-
-		ElvData e2;
-		if (!Unserialize(e2, buf))
-			FAIL("invalid serialization version");
-		if (e1.rating != e2.rating)
-			FAIL("rating is different");
-		if (e1.bWatched != e2.bWatched)
-			FAIL("bWatched is different");
-		if (e1.bTVOriginal != e2.bTVOriginal)
-			FAIL("bTVOriginal is different");
-		if (wcscmp(e1.sRating, e2.sRating) != 0)
-			FAIL("sRating is different");
-		if (wcscmp(e1.siEp, e2.siEp) != 0)
-			FAIL("siEp is different");
-		if (wcscmp(e1.title, e2.title) != 0)
-			FAIL("title is different");
-	}
-
-	TEST(SerializationPlusIO)
+	TEST(IO)
 	{
 		ElvData e1;
 		FromProlog(6, e1);
 		{
-			DatView dv{L"tmp.dat", CB_SERIALIZE_ELVDATA};
-			Serialize(e1, static_cast<unsigned char*>(dv.view));
+			FileView fv{L"tmp.dat", sizeof(e1)};
+			Write(fv, e1);
 		}
 		{
-			DatView dv{L"tmp.dat", CB_SERIALIZE_ELVDATA};
-
-			ElvData e2;
-			if (!Unserialize(e2, static_cast<unsigned char*>(dv.view)))
-				FAIL("invalid serialization version");
-			if (e1.rating != e2.rating)
-				FAIL("rating is different");
-			if (e1.bWatched != e2.bWatched)
+			FileView fv{L"tmp.dat", sizeof(e1)};
+			ElvData* e2 = Read(fv);
+			if (e1.rating != e2->rating)
+				FAIL("rating is different (%d/%d)", e1.rating, e2->rating);
+			if (e1.bWatched != e2->bWatched)
 				FAIL("bWatched is different");
-			if (e1.bTVOriginal != e2.bTVOriginal)
+			if (e1.bTVOriginal != e2->bTVOriginal)
 				FAIL("bTVOriginal is different");
-			if (wcscmp(e1.sRating, e2.sRating) != 0)
+			if (wcscmp(e1.sRating, e2->sRating) != 0)
 				FAIL("sRating is different");
-			if (wcscmp(e1.siEp, e2.siEp) != 0)
+			if (wcscmp(e1.siEp, e2->siEp) != 0)
 				FAIL("siEp is different");
-			if (wcscmp(e1.title, e2.title) != 0)
+			if (wcscmp(e1.title, e2->title) != 0)
 				FAIL("title is different");
 		}
-		DeleteFile(L"tmp.dat");
+		//DeleteFile(L"tmp.dat");
 	}
 };
 
@@ -109,8 +81,7 @@ int RunTests()
 		StrcpyWithSmallerDestination{},
 		//EpisodeDataFromWeb{},
 		EpisodeDataFromProlog{},
-		Serialization{},
-		SerializationPlusIO{},
+		IO{},
 	};
 
 	printf("Results (%llu tests):\n", sizeof(tests)/sizeof(*tests));