* Add in-kernel copying support for Linux (sendfile64(2), copy_file_range(2)), FreeBSD 13 (copy_file_range(2)), MacOS (copyfile(2)), and Windows (CopyFileExA).
* Fix macro name USE_COPY_FILE_RANGE.
* Minor bugfixes for userspace fallback.
* Fix linux sendfile64 bugs.
* Remove some overzealous asserts.
* Allow transmission-test-copy to take an optional argument for an external reference file.
* Fix return value error of tr_sys_path_copy.
* Use COPYFILE_ALL for Macs without COPYFILE_CLONE.
* Add in-kernel file copying for several platforms.
Numerous operating systems now have support for copying files directly in the
kernel, which is generally more efficient than copying in a userspace read(2)/
write(2) loop. (This becomes particularly relevant for 4th gen PCI-E storage,
which approaches the latency of DRAM.) For Linux I use sendfile64(2), and, for
later kernels, copy_file_range(2). FreeBSD 13 will also support
copy_file_range(2). MacOS has copyfile(2), and Windows has CopyFileExA.
Operating systems lacking such a syscall continue to use the existing
read(2)/write(2) loop.
* Appease uncrustify.
* Appease uncrustify.
* copy-test: generate random content at run time.
* copy-test: Stylistic changes and more check()s.
* copy-test: files_are_identical should follow test idioms
* tr_sys_path_copy: numerous tweaks as requested by review.
* s/old file/source file; s/new file/destination file.
* tr_sys_path_copy: handle win32 wide characters in paths.
* Uncrustify.
* test-copy: Use non-string create_file_with_contents.
* tr_sys_path_copy: numerous fixes.
Per review: generate test file content at runtime; tidy use of check();
fix style; re-measure file sizes in the copy; define a macro when the
system does not provide it; use Unicode APIs on Windows; and fix
documentation.
* Updated as per comments.
* Rebase kernel-copy changes onto 3.0 with gtest.
* Undo irrelevant comment change.
* Fix syntax error.
* Use tr_malloc() instead of tr_valloc().
* Use EXPECT instead of TR_ASSERT in gtest.
* Add error handling.
* Acceptable coding style has changed again.
Now it's camelCase. Also use nullptr instead of NULL, etc.
* Fix east/west const.
Co-authored-by: Mike Gelfand <mikedld@users.noreply.github.com>
Charles Kerr