istream/file: reorderd to improve struct packing

src/istream/FileIstream.cxx

@@ -31,19 +31,19 @@
 static constexpr Event::Duration file_retry_timeout = std::chrono::milliseconds(100);
 
 class FileIstream final : public Istream {
-	UniqueFileDescriptor fd;
-
 	/**
 	 * A timer to retry reading after EAGAIN.
 	 */
 	FineTimerEvent retry_event;
 
+	SliceFifoBuffer buffer;
+	const char *path;
+
 	off_t offset;
 
 	const off_t end_offset;
 
-	SliceFifoBuffer buffer;
-	const char *path;
+	UniqueFileDescriptor fd;
 
 	bool direct = false;
 
@@ -53,10 +53,10 @@ class FileIstream final : public Istream {
 		    off_t _start_offset, off_t _end_offset,
 		    const char *_path) noexcept
 		:Istream(p),
-		 fd(std::move(_fd)),
 		 retry_event(event_loop, BIND_THIS_METHOD(EventCallback)),
+		 path(_path),
 		 offset(_start_offset), end_offset(_end_offset),
-		 path(_path) {}
+		 fd(std::move(_fd)) {}
 
 private:
 	void EofDetected() noexcept {

src/istream/UringIstream.cxx

@@ -42,8 +42,6 @@ class CanceledUringIstream final : public Uring::Operation {
 class UringIstream final : public Istream, Uring::Operation {
 	Uring::Queue ů
 
-	UniqueFileDescriptor fd;
-
 	/**
 	 * Passed to the io_uring read operation.
 	 *
@@ -54,6 +52,13 @@ class UringIstream final : public Istream, Uring::Operation {
 	 */
 	std::unique_ptr<struct iovec> iov = std::make_unique<struct iovec>();
 
+	SliceFifoBuffer buffer;
+
+	/**
+	 * The path name.  Only used for error messages.
+	 */
+	const char *const path;
+
 	/**
 	 * The file offset of the next/pending read operation.  If
 	 * there is data in the #buffer, it precedes this offset.
@@ -66,12 +71,7 @@ class UringIstream final : public Istream, Uring::Operation {
 	 */
 	const off_t end_offset;
 
-	SliceFifoBuffer buffer;
-
-	/**
-	 * The path name.  Only used for error messages.
-	 */
-	const char *const path;
+	UniqueFileDescriptor fd;
 
 	bool direct = false;
 
@@ -80,9 +80,9 @@ class UringIstream final : public Istream, Uring::Operation {
 		     const char *_path, UniqueFileDescriptor &&_fd,
 		     off_t _start_offset, off_t _end_offset) noexcept
 		:Istream(p), uring(_uring),
-		 fd(std::move(_fd)),
+		 path(_path),
 		 offset(_start_offset), end_offset(_end_offset),
-		 path(_path)
+		 fd(std::move(_fd))
 	{
 	}
 

src/istream/UringSpliceIstream.cxx

@@ -35,11 +35,6 @@ class UringSpliceIstream final : public Istream, Uring::Operation {
 	 */
 	const char *const path;
 
-	/**
-	 * The actual file.
-	 */
-	UniqueFileDescriptor fd;
-
 	PipeLease pipe;
 
 	/**
@@ -61,6 +56,11 @@ class UringSpliceIstream final : public Istream, Uring::Operation {
 	 */
 	const off_t end_offset;
 
+	/**
+	 * The actual file.
+	 */
+	UniqueFileDescriptor fd;
+
 #ifndef NDEBUG
 	bool direct = false;
 #endif
@@ -73,9 +73,9 @@ class UringSpliceIstream final : public Istream, Uring::Operation {
 		:Istream(p), uring(_uring),
 		 defer_start(event_loop, BIND_THIS_METHOD(OnDeferredStart)),
 		 path(_path),
-		 fd(std::move(_fd)),
 		 pipe(_pipe_stock),
-		 offset(_start_offset), end_offset(_end_offset)
+		 offset(_start_offset), end_offset(_end_offset),
+		 fd(std::move(_fd))
 	{
 	}