This patch implements std::basic_syncbuf and std::basic_osyncstream as specified in paper p0053r7. For ease of reviewing I am submitting this patch before submitting a patch for std::basic_osyncstream.
Please note, this patch is not 100% complete. I plan on adding more tests (see comments), specifically I plan on adding tests for multithreading and synchronization.
Edit: I decided that it would be far easier for me to keep track of this and make changes that affect both std::basic_syncbuf and std::basic_osyncstream if both were in one patch.
The patch was originally written by @zoecarver
Implements
- P0053R7 - C++ Synchronized Buffered Ostream
- LWG-3127 basic_osyncstream::rdbuf needs a const_cast
- LWG-3334 basic_osyncstream move assignment and destruction calls basic_syncbuf::emit() twice
- LWG-3570 basic_osyncstream::emit should be an unformatted output function
- LWG-3867 Should std::basic_osyncstream's move assignment operator be noexcept?
We should mention this in a release note (but mention it is experimental).