This introduces new API for fd copying and modifies
php_stream_copy_to_stream_ex to use it. The implementation is separated
for various platforms and the end result have couple of implications:
- sendfile is used for copying file to generic fd (e.g. sockets) on all
platforms except Windows that use TransmitFile
- splice is used for copying between generic fds (e.g. sockets) on
Linux
- copy_file_range should get used on alpine linux with directly using
syscall (as musl does not seem to implement it)
- copy_file_range is used in the loop so it is used multiple times for
files bigger than 2GB on Linux.
- file mmap for copying is removed as it allowed crashing PHP when
another process modified mapped file - this was used as a fallback
for file copying. Sendfile should partially replace it.
- File to file copying was optimized on Windows with use of ReadFile
and WriteFile.
This also adds various tests including Linux unit tests.
Closes GH-20399
Co-authored-by: David Carlier <devnexen@gmail.com>
