Переписан для обычного diff

source/app.d

@@ -1,17 +1,20 @@
-import std.stdio;
-import libxdiff : MMFile;
+import libxdiff;
+
+import std.conv : to;
+import std.stdio : writefln, writeln;
+import std.file : read;
 
 void main()
 {
-	auto a = MMFile.fromBytes(cast(ubyte[]) "hello world\n");
-	auto b = MMFile.fromBytes(cast(ubyte[]) "hello world!\n");
+	auto file1 = new MMFile(cast(const(ubyte)[]) read("/tmp/diff1.d"));
+	auto file2 = new MMFile(cast(const(ubyte)[]) read("/tmp/diff2.d"));
 
-	auto patch = a.computePatch(b);
-	writeln("patch size: ", patch.size());
+	auto patch = file1.computePatch(file2);
 
-	auto res = a.applyPatch(patch);
-	writeln("apply success: ", res.success);
-	writeln(res.patched.asSlice()); // печатаем результат
-	// печатаем как есть (включая заголовок @@ и строки с '-'/'+' и '\n')
-	write(cast(string) MMFile.fromBlocksMoved(patch).asSlice());
+	writeln(patch);
+
+	writefln(
+		"file1: %s\nfile2: %s",
+		file1.size, file2.size
+	);
 }

source/libxdiff/init.d

@@ -0,0 +1,70 @@
+module libxdiff.init;
+
+import xdiff;
+
+import core.stdc.stdlib : malloc, free, realloc;
+import std.exception : enforce;
+import core.stdc.errno : errno;
+import core.stdc.string : strerror;
+import std.string : fromStringz;
+import std.conv : to;
+
+private __gshared bool _allocatorReady = false;
+package(libxdiff) alias ByteArray = const(ubyte)[];
+
+extern (C)
+{
+	private void* wrap_malloc(void*, uint size)
+	{
+		return malloc(size);
+	}
+
+	private void wrap_free(void*, void* p)
+	{
+		free(p);
+	}
+
+	private void* wrap_realloc(void*, void* p, uint size)
+	{
+		return realloc(p, size);
+	}
+}
+
+private void setAllocator()
+{
+	if (_allocatorReady)
+		return;
+
+	memallocator_t m = {null, &wrap_malloc, &wrap_free, &wrap_realloc};
+
+	enforce(xdl_set_allocator(&m) == 0,
+		"xdl_set_allocator failed: " ~ strerror(errno).fromStringz);
+	_allocatorReady = true;
+}
+
+mmfile_t initMmfile(size_t len)
+{
+	setAllocator();
+	mmfile_t mf;
+	enforce(xdl_init_mmfile(&mf, len.to!long, XDL_MMF_ATOMIC) == 0,
+		"xdl_init_mmfile failed: " ~ strerror(errno).fromStringz);
+	return mf;
+}
+
+abstract class MM
+{
+protected:
+	mmfile_t _inner;
+public:
+	final @property size_t size()
+	{
+		return xdl_mmfile_size(&_inner).to!size_t;
+	}
+
+	// Проверка «компактности» — содержимое лежит в одном блоке
+	// (важно для бинарных функций, которым нужно сплошное непрерывное представление).
+	final bool isCompact() const
+	{
+		return xdl_mmfile_iscompact(cast(mmfile_t*)&_inner) != 0;
+	}
+}

source/libxdiff/mmblocks.d

@@ -0,0 +1,41 @@
+module libxdiff.mmblocks;
+
+import xdiff;
+
+import libxdiff.init;
+
+import std.exception : enforce;
+import core.stdc.errno : errno;
+import core.stdc.string : strerror;
+import std.string : fromStringz;
+import std.conv : to;
+
+private enum DEFAULT_BSIZE = 8 * 1024;
+
+final class MMBlocks : MM
+{
+public:
+	this()
+	{
+		_inner = initMmfile(DEFAULT_BSIZE);
+	}
+
+	package(libxdiff) mmfile_t* ptr() @trusted
+	{
+		return &_inner;
+	}
+
+	const(ubyte)[] asSlice() @trusted
+	{
+		enforce(isCompact(), "MMFile must be compact for asSliceConst");
+		auto h = _inner.head;
+		return h is null || h.size <= 0 ? [] : (cast(const(ubyte)*) h.ptr)[0 .. h.size.to!size_t];
+	}
+
+	override string toString() const @trusted
+	{
+		enforce(isCompact(), "MMFile must be compact for asSliceConst");
+		auto h = _inner.head;
+		return h is null || h.size <= 0 ? [] : fromStringz(cast(const char*) h.ptr).idup;
+	}
+}

source/libxdiff/mmfile.d

@@ -0,0 +1,79 @@
+module libxdiff.mmfile;
+
+import xdiff;
+
+import libxdiff.init;
+import libxdiff.mmblocks;
+
+import std.exception : enforce;
+import core.stdc.errno : errno;
+import core.stdc.string : strerror;
+import std.string : fromStringz;
+import std.conv : to;
+import std.string : join, representation;
+
+final class MMFile : MM
+{
+private:
+	void _write(ByteArray data)
+	{
+		_inner = initMmfile(0);
+
+		if (data.length > 0)
+		{
+			auto length = data.length.to!long;
+			auto wrote = xdl_write_mmfile(&_inner, data.ptr, length);
+			enforce(wrote == length,
+				"xdl_write_mmfile wrote less than requested: " ~ strerror(errno).fromStringz);
+		}
+	}
+
+public:
+	this(ByteArray data)
+	{
+		_write(data);
+	}
+
+	this(string data)
+	{
+		_write(data.representation);
+	}
+
+	this(string[] data)
+	{
+		_write(data.join('\n').representation);
+	}
+
+	~this()
+	{
+		if (_inner.head !is null)
+			xdl_free_mmfile(&_inner);
+	}
+
+	MMBlocks computePatch(ref MMFile other, long ctxlen = 3)
+	{
+		auto patch = new MMBlocks();
+
+		extern (C) int emitToPatch(void* priv, mmbuffer_t* bufs, int num)
+		{
+			auto target = cast(MMBlocks) priv;
+			foreach (i; 0 .. num)
+			{
+				mmbuffer_t* buf = &bufs[i];
+				long written = xdl_writem_mmfile(target.ptr(), buf, 1);
+				if (written < 0 || written != buf.size)
+					return -1;
+			}
+			return 0;
+		}
+
+		xpparam_t xpp = {0};
+		xdemitconf_t xec = {ctxlen};
+		xdemitcb_t ecb = {cast(void*) patch, &emitToPatch};
+
+		enforce(xdl_diff(&_inner, &other._inner, &xpp, &xec, &ecb) == 0,
+			"xdl_diff failed: " ~ strerror(errno).fromStringz);
+
+		return patch;
+	}
+}

source/libxdiff/package.d

@@ -0,0 +1,4 @@
+module libxdiff;
+
+public import libxdiff.mmfile;
+public import libxdiff.mmblocks;