`set_read_timeout` and `set_write_timeout` can cause `ErrorKind::WouldBlock` on unix-y platforms.
This PR normalizes those cases to `ErrorKind::TimedOut`. This will make it simpler higher up in the
stack to deal with timeouts.
This also reverts a change to send_body that was originally added to
return the number of bytes written. It's no longer needed now that we
check the size of the reader in advance.
Fixes#76.
This deprecates timeout_read() and timeout_write() in favor of
timeout(). The new timeout method on Request takes a Duration instead
of a number of milliseconds, and is measured against overall request
time, not per-read time.
Once a request is started, the timeout is turned into a deadline
specific to that call. The deadline is used in conjunction with the
new DeadlineStream class, which sets a timeout on each read according
to the remaining time for the request. Once the request is done,
the DeadlineStream is unwrapped via .into::<Stream>() to become
an undecorated Stream again for return to the pool. Timeouts on the
stream are unset at this point.
Still to be done:
Add a setting on Agent for default timeout.
Change header-writing code to apply overall deadline rather than
per-write timeout.
Fixes#28.
