use _chsize_s on windows to grow file

Author: funny-falcon

src/utils/file.c

@@ -2717,21 +2717,19 @@ fio_send_file_write(FILE* out, send_file_state* st, char *buf, size_t len)
 	if (len == 0)
 		return true;
 
-#ifndef WIN32
+#ifdef WIN32
 	if (st->read_size > st->write_size &&
-		fseeko(out, st->read_size, SEEK_SET) != 0)
+		_chsize_s(fileno(out), st->read_size) != 0)
 	{
+		elog(WARNING, "Could not change file size to %lld: %m", st->read_size)
 		return false;
 	}
-#else
-	while (st->read_size > st->write_size)
+#endif
+	if (st->read_size > st->write_size &&
+		fseeko(out, st->read_size, SEEK_SET) != 0)
 	{
-		size_t wr = st->read_size - st->write_size;
-		wr = Min(wr, sizeof(zerobuf));
-		fwrite(zerobuf, 1, wr, out);
-		st->write_size += wr;
+		return false;
 	}
-#endif
 
 	if (fwrite(buf, 1, len, out) != len)
 	{