clean up and separate out fs_* files

src/fs_copydata.cpp

@@ -0,0 +1,53 @@
+/*
+  ISC License
+
+  Copyright (c) 2020, Antonio SJ Musumeci <trapexit@spawn.link>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#include "fs_copydata_copy_file_range.hpp"
+#include "fs_copydata_readwrite.hpp"
+#include "fs_fadvise.hpp"
+#include "fs_ficlone.hpp"
+#include "fs_ftruncate.hpp"
+
+#include <stddef.h>
+
+namespace fs
+{
+  int
+  copydata(const int    src_fd_,
+           const int    dst_fd_,
+           const size_t count_)
+  {
+    int rv;
+
+    rv = fs::ftruncate(dst_fd_,count_);
+    if(rv == -1)
+      return -1;
+
+    rv = fs::ficlone(src_fd_,dst_fd_);
+    if(rv != -1)
+      return rv;
+
+    fs::fadvise_willneed(src_fd_,0,count_);
+    fs::fadvise_sequential(src_fd_,0,count_);
+
+    rv = fs::copydata_copy_file_range(src_fd_,dst_fd_);
+    if(rv != -1)
+      return rv;
+
+    return fs::copydata_readwrite(src_fd_,dst_fd_);
+  }
+}